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Diffstat (limited to 'gnu/gcc2/lib/reload.c')
| -rw-r--r-- | gnu/gcc2/lib/reload.c | 5435 |
1 files changed, 0 insertions, 5435 deletions
diff --git a/gnu/gcc2/lib/reload.c b/gnu/gcc2/lib/reload.c deleted file mode 100644 index 868c96780fc3..000000000000 --- a/gnu/gcc2/lib/reload.c +++ /dev/null @@ -1,5435 +0,0 @@ -/* Search an insn for pseudo regs that must be in hard regs and are not. - Copyright (C) 1987, 1988, 1989, 1992, 1993 Free Software Foundation, Inc. - -This file is part of GNU CC. - -GNU CC is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. - -GNU CC is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with GNU CC; see the file COPYING. If not, write to -the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ - - -/* This file contains subroutines used only from the file reload1.c. - It knows how to scan one insn for operands and values - that need to be copied into registers to make valid code. - It also finds other operands and values which are valid - but for which equivalent values in registers exist and - ought to be used instead. - - Before processing the first insn of the function, call `init_reload'. - - To scan an insn, call `find_reloads'. This does two things: - 1. sets up tables describing which values must be reloaded - for this insn, and what kind of hard regs they must be reloaded into; - 2. optionally record the locations where those values appear in - the data, so they can be replaced properly later. - This is done only if the second arg to `find_reloads' is nonzero. - - The third arg to `find_reloads' specifies the number of levels - of indirect addressing supported by the machine. If it is zero, - indirect addressing is not valid. If it is one, (MEM (REG n)) - is valid even if (REG n) did not get a hard register; if it is two, - (MEM (MEM (REG n))) is also valid even if (REG n) did not get a - hard register, and similarly for higher values. - - Then you must choose the hard regs to reload those pseudo regs into, - and generate appropriate load insns before this insn and perhaps - also store insns after this insn. Set up the array `reload_reg_rtx' - to contain the REG rtx's for the registers you used. In some - cases `find_reloads' will return a nonzero value in `reload_reg_rtx' - for certain reloads. Then that tells you which register to use, - so you do not need to allocate one. But you still do need to add extra - instructions to copy the value into and out of that register. - - Finally you must call `subst_reloads' to substitute the reload reg rtx's - into the locations already recorded. - -NOTE SIDE EFFECTS: - - find_reloads can alter the operands of the instruction it is called on. - - 1. Two operands of any sort may be interchanged, if they are in a - commutative instruction. - This happens only if find_reloads thinks the instruction will compile - better that way. - - 2. Pseudo-registers that are equivalent to constants are replaced - with those constants if they are not in hard registers. - -1 happens every time find_reloads is called. -2 happens only when REPLACE is 1, which is only when -actually doing the reloads, not when just counting them. - - -Using a reload register for several reloads in one insn: - -When an insn has reloads, it is considered as having three parts: -the input reloads, the insn itself after reloading, and the output reloads. -Reloads of values used in memory addresses are often needed for only one part. - -When this is so, reload_when_needed records which part needs the reload. -Two reloads for different parts of the insn can share the same reload -register. - -When a reload is used for addresses in multiple parts, or when it is -an ordinary operand, it is classified as RELOAD_OTHER, and cannot share -a register with any other reload. */ - -#define REG_OK_STRICT - -#include "config.h" -#include "rtl.h" -#include "insn-config.h" -#include "insn-codes.h" -#include "recog.h" -#include "reload.h" -#include "regs.h" -#include "hard-reg-set.h" -#include "flags.h" -#include "real.h" - -#ifndef REGISTER_MOVE_COST -#define REGISTER_MOVE_COST(x, y) 2 -#endif - -/* The variables set up by `find_reloads' are: - - n_reloads number of distinct reloads needed; max reload # + 1 - tables indexed by reload number - reload_in rtx for value to reload from - reload_out rtx for where to store reload-reg afterward if nec - (often the same as reload_in) - reload_reg_class enum reg_class, saying what regs to reload into - reload_inmode enum machine_mode; mode this operand should have - when reloaded, on input. - reload_outmode enum machine_mode; mode this operand should have - when reloaded, on output. - reload_optional char, nonzero for an optional reload. - Optional reloads are ignored unless the - value is already sitting in a register. - reload_inc int, positive amount to increment or decrement by if - reload_in is a PRE_DEC, PRE_INC, POST_DEC, POST_INC. - Ignored otherwise (don't assume it is zero). - reload_in_reg rtx. A reg for which reload_in is the equivalent. - If reload_in is a symbol_ref which came from - reg_equiv_constant, then this is the pseudo - which has that symbol_ref as equivalent. - reload_reg_rtx rtx. This is the register to reload into. - If it is zero when `find_reloads' returns, - you must find a suitable register in the class - specified by reload_reg_class, and store here - an rtx for that register with mode from - reload_inmode or reload_outmode. - reload_nocombine char, nonzero if this reload shouldn't be - combined with another reload. - reload_opnum int, operand number being reloaded. This is - used to group related reloads and need not always - be equal to the actual operand number in the insn, - though it current will be; for in-out operands, it - is one of the two operand numbers. - reload_when_needed enum, classifies reload as needed either for - addressing an input reload, addressing an output, - for addressing a non-reloaded mem ref, - or for unspecified purposes (i.e., more than one - of the above). - reload_secondary_reload int, gives the reload number of a secondary - reload, when needed; otherwise -1 - reload_secondary_p int, 1 if this is a secondary register for one - or more reloads. - reload_secondary_icode enum insn_code, if a secondary reload is required, - gives the INSN_CODE that uses the secondary - reload as a scratch register, or CODE_FOR_nothing - if the secondary reload register is to be an - intermediate register. */ -int n_reloads; - -rtx reload_in[MAX_RELOADS]; -rtx reload_out[MAX_RELOADS]; -enum reg_class reload_reg_class[MAX_RELOADS]; -enum machine_mode reload_inmode[MAX_RELOADS]; -enum machine_mode reload_outmode[MAX_RELOADS]; -rtx reload_reg_rtx[MAX_RELOADS]; -char reload_optional[MAX_RELOADS]; -int reload_inc[MAX_RELOADS]; -rtx reload_in_reg[MAX_RELOADS]; -char reload_nocombine[MAX_RELOADS]; -int reload_opnum[MAX_RELOADS]; -enum reload_type reload_when_needed[MAX_RELOADS]; -int reload_secondary_reload[MAX_RELOADS]; -int reload_secondary_p[MAX_RELOADS]; -enum insn_code reload_secondary_icode[MAX_RELOADS]; - -/* All the "earlyclobber" operands of the current insn - are recorded here. */ -int n_earlyclobbers; -rtx reload_earlyclobbers[MAX_RECOG_OPERANDS]; - -int reload_n_operands; - -/* Replacing reloads. - - If `replace_reloads' is nonzero, then as each reload is recorded - an entry is made for it in the table `replacements'. - Then later `subst_reloads' can look through that table and - perform all the replacements needed. */ - -/* Nonzero means record the places to replace. */ -static int replace_reloads; - -/* Each replacement is recorded with a structure like this. */ -struct replacement -{ - rtx *where; /* Location to store in */ - rtx *subreg_loc; /* Location of SUBREG if WHERE is inside - a SUBREG; 0 otherwise. */ - int what; /* which reload this is for */ - enum machine_mode mode; /* mode it must have */ -}; - -static struct replacement replacements[MAX_RECOG_OPERANDS * ((MAX_REGS_PER_ADDRESS * 2) + 1)]; - -/* Number of replacements currently recorded. */ -static int n_replacements; - -/* Used to track what is modified by an operand. */ -struct decomposition -{ - int reg_flag; /* Nonzero if referencing a register. */ - int safe; /* Nonzero if this can't conflict with anything. */ - rtx base; /* Base adddress for MEM. */ - HOST_WIDE_INT start; /* Starting offset or register number. */ - HOST_WIDE_INT end; /* Endinf offset or register number. */ -}; - -/* MEM-rtx's created for pseudo-regs in stack slots not directly addressable; - (see reg_equiv_address). */ -static rtx memlocs[MAX_RECOG_OPERANDS * ((MAX_REGS_PER_ADDRESS * 2) + 1)]; -static int n_memlocs; - -#ifdef SECONDARY_MEMORY_NEEDED - -/* Save MEMs needed to copy from one class of registers to another. One MEM - is used per mode, but normally only one or two modes are ever used. - - We keep two versions, before and after register elimination. The one - after register elimination is record separately for each operand. This - is done in case the address is not valid to be sure that we separately - reload each. */ - -static rtx secondary_memlocs[NUM_MACHINE_MODES]; -static rtx secondary_memlocs_elim[NUM_MACHINE_MODES][MAX_RECOG_OPERANDS]; -#endif - -/* The instruction we are doing reloads for; - so we can test whether a register dies in it. */ -static rtx this_insn; - -/* Nonzero if this instruction is a user-specified asm with operands. */ -static int this_insn_is_asm; - -/* If hard_regs_live_known is nonzero, - we can tell which hard regs are currently live, - at least enough to succeed in choosing dummy reloads. */ -static int hard_regs_live_known; - -/* Indexed by hard reg number, - element is nonegative if hard reg has been spilled. - This vector is passed to `find_reloads' as an argument - and is not changed here. */ -static short *static_reload_reg_p; - -/* Set to 1 in subst_reg_equivs if it changes anything. */ -static int subst_reg_equivs_changed; - -/* On return from push_reload, holds the reload-number for the OUT - operand, which can be different for that from the input operand. */ -static int output_reloadnum; - -static enum reg_class find_secondary_reload PROTO((rtx, enum reg_class, - enum machine_mode, int, - enum insn_code *, - enum machine_mode *, - enum reg_class *, - enum insn_code *, - enum machine_mode *)); -static int push_reload PROTO((rtx, rtx, rtx *, rtx *, enum reg_class, - enum machine_mode, enum machine_mode, - int, int, int, enum reload_type)); -static void push_replacement PROTO((rtx *, int, enum machine_mode)); -static void combine_reloads PROTO((void)); -static rtx find_dummy_reload PROTO((rtx, rtx, rtx *, rtx *, - enum reg_class, int)); -static int hard_reg_set_here_p PROTO((int, int, rtx)); -static struct decomposition decompose PROTO((rtx)); -static int immune_p PROTO((rtx, rtx, struct decomposition)); -static int alternative_allows_memconst PROTO((char *, int)); -static rtx find_reloads_toplev PROTO((rtx, int, enum reload_type, int, int)); -static rtx make_memloc PROTO((rtx, int)); -static int find_reloads_address PROTO((enum machine_mode, rtx *, rtx, rtx *, - int, enum reload_type, int)); -static rtx subst_reg_equivs PROTO((rtx)); -static rtx subst_indexed_address PROTO((rtx)); -static int find_reloads_address_1 PROTO((rtx, int, rtx *, int, - enum reload_type,int)); -static void find_reloads_address_part PROTO((rtx, rtx *, enum reg_class, - enum machine_mode, int, - enum reload_type, int)); -static int find_inc_amount PROTO((rtx, rtx)); - -#ifdef HAVE_SECONDARY_RELOADS - -/* Determine if any secondary reloads are needed for loading (if IN_P is - non-zero) or storing (if IN_P is zero) X to or from a reload register of - register class RELOAD_CLASS in mode RELOAD_MODE. - - Return the register class of a secondary reload register, or NO_REGS if - none. *PMODE is set to the mode that the register is required in. - If the reload register is needed as a scratch register instead of an - intermediate register, *PICODE is set to the insn_code of the insn to be - used to load or store the primary reload register; otherwise *PICODE - is set to CODE_FOR_nothing. - - In some cases (such as storing MQ into an external memory location on - the RT), both an intermediate register and a scratch register. In that - case, *PICODE is set to CODE_FOR_nothing, the class for the intermediate - register is returned, and the *PTERTIARY_... variables are set to describe - the scratch register. */ - -static enum reg_class -find_secondary_reload (x, reload_class, reload_mode, in_p, picode, pmode, - ptertiary_class, ptertiary_icode, ptertiary_mode) - rtx x; - enum reg_class reload_class; - enum machine_mode reload_mode; - int in_p; - enum insn_code *picode; - enum machine_mode *pmode; - enum reg_class *ptertiary_class; - enum insn_code *ptertiary_icode; - enum machine_mode *ptertiary_mode; -{ - enum reg_class class = NO_REGS; - enum machine_mode mode = reload_mode; - enum insn_code icode = CODE_FOR_nothing; - enum reg_class t_class = NO_REGS; - enum machine_mode t_mode = VOIDmode; - enum insn_code t_icode = CODE_FOR_nothing; - - /* If X is a pseudo-register that has an equivalent MEM (actually, if it - is still a pseudo-register by now, it *must* have an equivalent MEM - but we don't want to assume that), use that equivalent when seeing if - a secondary reload is needed since whether or not a reload is needed - might be sensitive to the form of the MEM. */ - - if (GET_CODE (x) == REG && REGNO (x) >= FIRST_PSEUDO_REGISTER - && reg_equiv_mem[REGNO (x)] != 0) - x = reg_equiv_mem[REGNO (x)]; - -#ifdef SECONDARY_INPUT_RELOAD_CLASS - if (in_p) - class = SECONDARY_INPUT_RELOAD_CLASS (reload_class, reload_mode, x); -#endif - -#ifdef SECONDARY_OUTPUT_RELOAD_CLASS - if (! in_p) - class = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class, reload_mode, x); -#endif - - /* If we don't need any secondary registers, go away; the rest of the - values won't be used. */ - if (class == NO_REGS) - return NO_REGS; - - /* Get a possible insn to use. If the predicate doesn't accept X, don't - use the insn. */ - - icode = (in_p ? reload_in_optab[(int) reload_mode] - : reload_out_optab[(int) reload_mode]); - - if (icode != CODE_FOR_nothing - && insn_operand_predicate[(int) icode][in_p] - && (! (insn_operand_predicate[(int) icode][in_p]) (x, reload_mode))) - icode = CODE_FOR_nothing; - - /* If we will be using an insn, see if it can directly handle the reload - register we will be using. If it can, the secondary reload is for a - scratch register. If it can't, we will use the secondary reload for - an intermediate register and require a tertiary reload for the scratch - register. */ - - if (icode != CODE_FOR_nothing) - { - /* If IN_P is non-zero, the reload register will be the output in - operand 0. If IN_P is zero, the reload register will be the input - in operand 1. Outputs should have an initial "=", which we must - skip. */ - - char insn_letter = insn_operand_constraint[(int) icode][!in_p][in_p]; - enum reg_class insn_class - = (insn_letter == 'r' ? GENERAL_REGS - : REG_CLASS_FROM_LETTER (insn_letter)); - - if (insn_class == NO_REGS - || (in_p && insn_operand_constraint[(int) icode][!in_p][0] != '=') - /* The scratch register's constraint must start with "=&". */ - || insn_operand_constraint[(int) icode][2][0] != '=' - || insn_operand_constraint[(int) icode][2][1] != '&') - abort (); - - if (reg_class_subset_p (reload_class, insn_class)) - mode = insn_operand_mode[(int) icode][2]; - else - { - char t_letter = insn_operand_constraint[(int) icode][2][2]; - class = insn_class; - t_mode = insn_operand_mode[(int) icode][2]; - t_class = (t_letter == 'r' ? GENERAL_REGS - : REG_CLASS_FROM_LETTER (t_letter)); - t_icode = icode; - icode = CODE_FOR_nothing; - } - } - - *pmode = mode; - *picode = icode; - *ptertiary_class = t_class; - *ptertiary_mode = t_mode; - *ptertiary_icode = t_icode; - - return class; -} -#endif /* HAVE_SECONDARY_RELOADS */ - -#ifdef SECONDARY_MEMORY_NEEDED - -/* Return a memory location that will be used to copy X in mode MODE. - If we haven't already made a location for this mode in this insn, - call find_reloads_address on the location being returned. */ - -rtx -get_secondary_mem (x, mode, opnum, type) - rtx x; - enum machine_mode mode; - int opnum; - enum reload_type type; -{ - rtx loc; - int mem_valid; - - /* If MODE is narrower than a word, widen it. This is required because - most machines that require these memory locations do not support - short load and stores from all registers (e.g., FP registers). We could - possibly conditionalize this, but we lose nothing by doing the wider - mode. */ - - if (GET_MODE_BITSIZE (mode) < BITS_PER_WORD) - mode = mode_for_size (BITS_PER_WORD, GET_MODE_CLASS (mode), 0); - - /* If we already have made a MEM for this operand in MODE, return it. */ - if (secondary_memlocs_elim[(int) mode][opnum] != 0) - return secondary_memlocs_elim[(int) mode][opnum]; - - /* If this is the first time we've tried to get a MEM for this mode, - allocate a new one. `something_changed' in reload will get set - by noticing that the frame size has changed. */ - - if (secondary_memlocs[(int) mode] == 0) - { -#ifdef SECONDARY_MEMORY_NEEDED_RTX - secondary_memlocs[(int) mode] = SECONDARY_MEMORY_NEEDED_RTX (mode); -#else - secondary_memlocs[(int) mode] - = assign_stack_local (mode, GET_MODE_SIZE (mode), 0); -#endif - } - - /* Get a version of the address doing any eliminations needed. If that - didn't give us a new MEM, make a new one if it isn't valid. */ - - loc = eliminate_regs (secondary_memlocs[(int) mode], VOIDmode, NULL_RTX); - mem_valid = strict_memory_address_p (mode, XEXP (loc, 0)); - - if (! mem_valid && loc == secondary_memlocs[(int) mode]) - loc = copy_rtx (loc); - - /* The only time the call below will do anything is if the stack - offset is too large. In that case IND_LEVELS doesn't matter, so we - can just pass a zero. Adjust the type to be the address of the - corresponding object. If the address was valid, save the eliminated - address. If it wasn't valid, we need to make a reload each time, so - don't save it. */ - - if (! mem_valid) - { - type = (type == RELOAD_FOR_INPUT ? RELOAD_FOR_INPUT_ADDRESS - : type == RELOAD_FOR_OUTPUT ? RELOAD_FOR_OUTPUT_ADDRESS - : RELOAD_OTHER); - - find_reloads_address (mode, NULL_PTR, XEXP (loc, 0), &XEXP (loc, 0), - opnum, type, 0); - } - - secondary_memlocs_elim[(int) mode][opnum] = loc; - return loc; -} - -/* Clear any secondary memory locations we've made. */ - -void -clear_secondary_mem () -{ - bzero (secondary_memlocs, sizeof secondary_memlocs); -} -#endif /* SECONDARY_MEMORY_NEEDED */ - -/* Record one reload that needs to be performed. - IN is an rtx saying where the data are to be found before this instruction. - OUT says where they must be stored after the instruction. - (IN is zero for data not read, and OUT is zero for data not written.) - INLOC and OUTLOC point to the places in the instructions where - IN and OUT were found. - If IN and OUT are both non-zero, it means the same register must be used - to reload both IN and OUT. - - CLASS is a register class required for the reloaded data. - INMODE is the machine mode that the instruction requires - for the reg that replaces IN and OUTMODE is likewise for OUT. - - If IN is zero, then OUT's location and mode should be passed as - INLOC and INMODE. - - STRICT_LOW is the 1 if there is a containing STRICT_LOW_PART rtx. - - OPTIONAL nonzero means this reload does not need to be performed: - it can be discarded if that is more convenient. - - OPNUM and TYPE say what the purpose of this reload is. - - The return value is the reload-number for this reload. - - If both IN and OUT are nonzero, in some rare cases we might - want to make two separate reloads. (Actually we never do this now.) - Therefore, the reload-number for OUT is stored in - output_reloadnum when we return; the return value applies to IN. - Usually (presently always), when IN and OUT are nonzero, - the two reload-numbers are equal, but the caller should be careful to - distinguish them. */ - -static int -push_reload (in, out, inloc, outloc, class, - inmode, outmode, strict_low, optional, opnum, type) - register rtx in, out; - rtx *inloc, *outloc; - enum reg_class class; - enum machine_mode inmode, outmode; - int strict_low; - int optional; - int opnum; - enum reload_type type; -{ - register int i; - int dont_share = 0; - rtx *in_subreg_loc = 0, *out_subreg_loc = 0; - int secondary_reload = -1; - enum insn_code secondary_icode = CODE_FOR_nothing; - - /* Compare two RTX's. */ -#define MATCHES(x, y) \ - (x == y || (x != 0 && (GET_CODE (x) == REG \ - ? GET_CODE (y) == REG && REGNO (x) == REGNO (y) \ - : rtx_equal_p (x, y) && ! side_effects_p (x)))) - - /* Indicates if two reloads purposes are for similar enough things that we - can merge their reloads. */ -#define MERGABLE_RELOADS(when1, when2, op1, op2) \ - ((when1) == RELOAD_OTHER || (when2) == RELOAD_OTHER \ - || ((when1) == (when2) && (op1) == (op2)) \ - || ((when1) == RELOAD_FOR_INPUT && (when2) == RELOAD_FOR_INPUT) \ - || ((when1) == RELOAD_FOR_OPERAND_ADDRESS \ - && (when2) == RELOAD_FOR_OPERAND_ADDRESS) \ - || ((when1) == RELOAD_FOR_OTHER_ADDRESS \ - && (when2) == RELOAD_FOR_OTHER_ADDRESS)) - - /* Nonzero if these two reload purposes produce RELOAD_OTHER when merged. */ -#define MERGE_TO_OTHER(when1, when2, op1, op2) \ - ((when1) != (when2) \ - || ! ((op1) == (op2) \ - || (when1) == RELOAD_FOR_INPUT \ - || (when1) == RELOAD_FOR_OPERAND_ADDRESS \ - || (when1) == RELOAD_FOR_OTHER_ADDRESS)) - - /* INMODE and/or OUTMODE could be VOIDmode if no mode - has been specified for the operand. In that case, - use the operand's mode as the mode to reload. */ - if (inmode == VOIDmode && in != 0) - inmode = GET_MODE (in); - if (outmode == VOIDmode && out != 0) - outmode = GET_MODE (out); - - /* If IN is a pseudo register everywhere-equivalent to a constant, and - it is not in a hard register, reload straight from the constant, - since we want to get rid of such pseudo registers. - Often this is done earlier, but not always in find_reloads_address. */ - if (in != 0 && GET_CODE (in) == REG) - { - register int regno = REGNO (in); - - if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 - && reg_equiv_constant[regno] != 0) - in = reg_equiv_constant[regno]; - } - - /* Likewise for OUT. Of course, OUT will never be equivalent to - an actual constant, but it might be equivalent to a memory location - (in the case of a parameter). */ - if (out != 0 && GET_CODE (out) == REG) - { - register int regno = REGNO (out); - - if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 - && reg_equiv_constant[regno] != 0) - out = reg_equiv_constant[regno]; - } - - /* If we have a read-write operand with an address side-effect, - change either IN or OUT so the side-effect happens only once. */ - if (in != 0 && out != 0 && GET_CODE (in) == MEM && rtx_equal_p (in, out)) - { - if (GET_CODE (XEXP (in, 0)) == POST_INC - || GET_CODE (XEXP (in, 0)) == POST_DEC) - in = gen_rtx (MEM, GET_MODE (in), XEXP (XEXP (in, 0), 0)); - if (GET_CODE (XEXP (in, 0)) == PRE_INC - || GET_CODE (XEXP (in, 0)) == PRE_DEC) - out = gen_rtx (MEM, GET_MODE (out), XEXP (XEXP (out, 0), 0)); - } - - /* If we are reloading a (SUBREG (MEM ...) ...) or (SUBREG constant ...), - really reload just the inside expression in its own mode. - If we have (SUBREG:M1 (REG:M2 ...) ...) with M1 wider than M2 and the - register is a pseudo, this will become the same as the above case. - Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where - either M1 is not valid for R or M2 is wider than a word but we only - need one word to store an M2-sized quantity in R. - (However, if OUT is nonzero, we need to reload the reg *and* - the subreg, so do nothing here, and let following statement handle it.) - - Note that the case of (SUBREG (CONST_INT...)...) is handled elsewhere; - we can't handle it here because CONST_INT does not indicate a mode. - - Similarly, we must reload the inside expression if we have a - STRICT_LOW_PART (presumably, in == out in the cas). - - Also reload the inner expression if it does not require a secondary - reload but the SUBREG does. */ - - if (in != 0 && GET_CODE (in) == SUBREG - && (GET_CODE (SUBREG_REG (in)) != REG - || strict_low - || (GET_CODE (SUBREG_REG (in)) == REG - && REGNO (SUBREG_REG (in)) >= FIRST_PSEUDO_REGISTER - && (GET_MODE_SIZE (inmode) - > GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))))) - || (REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER - /* The case where out is nonzero - is handled differently in the following statement. */ - && (out == 0 || SUBREG_WORD (in) == 0) - && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (in)), inmode) - || (GET_MODE_SIZE (inmode) <= UNITS_PER_WORD - && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) - > UNITS_PER_WORD) - && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) - / UNITS_PER_WORD) - != HARD_REGNO_NREGS (REGNO (SUBREG_REG (in)), - GET_MODE (SUBREG_REG (in))))))) -#ifdef SECONDARY_INPUT_RELOAD_CLASS - || (SECONDARY_INPUT_RELOAD_CLASS (class, inmode, in) != NO_REGS - && (SECONDARY_INPUT_RELOAD_CLASS (class, - GET_MODE (SUBREG_REG (in)), - SUBREG_REG (in)) - == NO_REGS)) -#endif - )) - { - in_subreg_loc = inloc; - inloc = &SUBREG_REG (in); - in = *inloc; -#if ! defined(BYTE_LOADS_ZERO_EXTEND) && ! defined(BYTE_LOADS_SIGN_EXTEND) - if (GET_CODE (in) == MEM) - /* This is supposed to happen only for paradoxical subregs made by - combine.c. (SUBREG (MEM)) isn't supposed to occur other ways. */ - if (GET_MODE_SIZE (GET_MODE (in)) > GET_MODE_SIZE (inmode)) - abort (); -#endif - inmode = GET_MODE (in); - } - - /* Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where - either M1 is not valid for R or M2 is wider than a word but we only - need one word to store an M2-sized quantity in R. - - However, we must reload the inner reg *as well as* the subreg in - that case. */ - - if (in != 0 && GET_CODE (in) == SUBREG - && GET_CODE (SUBREG_REG (in)) == REG - && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER - && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (in)), inmode) - || (GET_MODE_SIZE (inmode) <= UNITS_PER_WORD - && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) - > UNITS_PER_WORD) - && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) - / UNITS_PER_WORD) - != HARD_REGNO_NREGS (REGNO (SUBREG_REG (in)), - GET_MODE (SUBREG_REG (in))))))) - { - push_reload (SUBREG_REG (in), NULL_RTX, &SUBREG_REG (in), NULL_PTR, - GENERAL_REGS, VOIDmode, VOIDmode, 0, 0, opnum, type); - } - - - /* Similarly for paradoxical and problematical SUBREGs on the output. - Note that there is no reason we need worry about the previous value - of SUBREG_REG (out); even if wider than out, - storing in a subreg is entitled to clobber it all - (except in the case of STRICT_LOW_PART, - and in that case the constraint should label it input-output.) */ - if (out != 0 && GET_CODE (out) == SUBREG - && (GET_CODE (SUBREG_REG (out)) != REG - || strict_low - || (GET_CODE (SUBREG_REG (out)) == REG - && REGNO (SUBREG_REG (out)) >= FIRST_PSEUDO_REGISTER - && (GET_MODE_SIZE (outmode) - > GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))))) - || (GET_CODE (SUBREG_REG (out)) == REG - && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER - && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (out)), outmode) - || (GET_MODE_SIZE (outmode) <= UNITS_PER_WORD - && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))) - > UNITS_PER_WORD) - && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))) - / UNITS_PER_WORD) - != HARD_REGNO_NREGS (REGNO (SUBREG_REG (out)), - GET_MODE (SUBREG_REG (out))))))) -#ifdef SECONDARY_OUTPUT_RELOAD_CLASS - || (SECONDARY_OUTPUT_RELOAD_CLASS (class, outmode, out) != NO_REGS - && (SECONDARY_OUTPUT_RELOAD_CLASS (class, - GET_MODE (SUBREG_REG (out)), - SUBREG_REG (out)) - == NO_REGS)) -#endif - )) - { - out_subreg_loc = outloc; - outloc = &SUBREG_REG (out); - out = *outloc; -#if ! defined(BYTE_LOADS_ZERO_EXTEND) && ! defined(BYTE_LOADS_SIGN_EXTEND) - if (GET_CODE (out) == MEM - && GET_MODE_SIZE (GET_MODE (out)) > GET_MODE_SIZE (outmode)) - abort (); -#endif - outmode = GET_MODE (out); - } - - /* If IN appears in OUT, we can't share any input-only reload for IN. */ - if (in != 0 && out != 0 && GET_CODE (out) == MEM - && (GET_CODE (in) == REG || GET_CODE (in) == MEM) - && reg_overlap_mentioned_for_reload_p (in, XEXP (out, 0))) - dont_share = 1; - - /* If IN is a SUBREG of a hard register, make a new REG. This - simplifies some of the cases below. */ - - if (in != 0 && GET_CODE (in) == SUBREG && GET_CODE (SUBREG_REG (in)) == REG - && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER) - in = gen_rtx (REG, GET_MODE (in), - REGNO (SUBREG_REG (in)) + SUBREG_WORD (in)); - - /* Similarly for OUT. */ - if (out != 0 && GET_CODE (out) == SUBREG - && GET_CODE (SUBREG_REG (out)) == REG - && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER) - out = gen_rtx (REG, GET_MODE (out), - REGNO (SUBREG_REG (out)) + SUBREG_WORD (out)); - - /* Narrow down the class of register wanted if that is - desirable on this machine for efficiency. */ - if (in != 0) - class = PREFERRED_RELOAD_CLASS (in, class); - - /* Output reloads may need analogous treatment, different in detail. */ -#ifdef PREFERRED_OUTPUT_RELOAD_CLASS - if (out != 0) - class = PREFERRED_OUTPUT_RELOAD_CLASS (out, class); -#endif - - /* Make sure we use a class that can handle the actual pseudo - inside any subreg. For example, on the 386, QImode regs - can appear within SImode subregs. Although GENERAL_REGS - can handle SImode, QImode needs a smaller class. */ -#ifdef LIMIT_RELOAD_CLASS - if (in_subreg_loc) - class = LIMIT_RELOAD_CLASS (inmode, class); - else if (in != 0 && GET_CODE (in) == SUBREG) - class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (in)), class); - - if (out_subreg_loc) - class = LIMIT_RELOAD_CLASS (outmode, class); - if (out != 0 && GET_CODE (out) == SUBREG) - class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (out)), class); -#endif - - /* Verify that this class is at least possible for the mode that - is specified. */ - if (this_insn_is_asm) - { - enum machine_mode mode; - if (GET_MODE_SIZE (inmode) > GET_MODE_SIZE (outmode)) - mode = inmode; - else - mode = outmode; - if (mode == VOIDmode) - { - error_for_asm (this_insn, "cannot reload integer constant operand in `asm'"); - mode = word_mode; - if (in != 0) - inmode = word_mode; - if (out != 0) - outmode = word_mode; - } - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (HARD_REGNO_MODE_OK (i, mode) - && TEST_HARD_REG_BIT (reg_class_contents[(int) class], i)) - { - int nregs = HARD_REGNO_NREGS (i, mode); - - int j; - for (j = 1; j < nregs; j++) - if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], i + j)) - break; - if (j == nregs) - break; - } - if (i == FIRST_PSEUDO_REGISTER) - { - error_for_asm (this_insn, "impossible register constraint in `asm'"); - class = ALL_REGS; - } - } - - if (class == NO_REGS) - abort (); - - /* We can use an existing reload if the class is right - and at least one of IN and OUT is a match - and the other is at worst neutral. - (A zero compared against anything is neutral.) - - If SMALL_REGISTER_CLASSES, don't use existing reloads unless they are - for the same thing since that can cause us to need more reload registers - than we otherwise would. */ - - for (i = 0; i < n_reloads; i++) - if ((reg_class_subset_p (class, reload_reg_class[i]) - || reg_class_subset_p (reload_reg_class[i], class)) - /* If the existing reload has a register, it must fit our class. */ - && (reload_reg_rtx[i] == 0 - || TEST_HARD_REG_BIT (reg_class_contents[(int) class], - true_regnum (reload_reg_rtx[i]))) - && ((in != 0 && MATCHES (reload_in[i], in) && ! dont_share - && (out == 0 || reload_out[i] == 0 || MATCHES (reload_out[i], out))) - || - (out != 0 && MATCHES (reload_out[i], out) - && (in == 0 || reload_in[i] == 0 || MATCHES (reload_in[i], in)))) - && (reg_class_size[(int) class] == 1 -#ifdef SMALL_REGISTER_CLASSES - || 1 -#endif - ) - && MERGABLE_RELOADS (type, reload_when_needed[i], - opnum, reload_opnum[i])) - break; - - /* Reloading a plain reg for input can match a reload to postincrement - that reg, since the postincrement's value is the right value. - Likewise, it can match a preincrement reload, since we regard - the preincrementation as happening before any ref in this insn - to that register. */ - if (i == n_reloads) - for (i = 0; i < n_reloads; i++) - if ((reg_class_subset_p (class, reload_reg_class[i]) - || reg_class_subset_p (reload_reg_class[i], class)) - /* If the existing reload has a register, it must fit our class. */ - && (reload_reg_rtx[i] == 0 - || TEST_HARD_REG_BIT (reg_class_contents[(int) class], - true_regnum (reload_reg_rtx[i]))) - && out == 0 && reload_out[i] == 0 && reload_in[i] != 0 - && ((GET_CODE (in) == REG - && (GET_CODE (reload_in[i]) == POST_INC - || GET_CODE (reload_in[i]) == POST_DEC - || GET_CODE (reload_in[i]) == PRE_INC - || GET_CODE (reload_in[i]) == PRE_DEC) - && MATCHES (XEXP (reload_in[i], 0), in)) - || - (GET_CODE (reload_in[i]) == REG - && (GET_CODE (in) == POST_INC - || GET_CODE (in) == POST_DEC - || GET_CODE (in) == PRE_INC - || GET_CODE (in) == PRE_DEC) - && MATCHES (XEXP (in, 0), reload_in[i]))) - && (reg_class_size[(int) class] == 1 -#ifdef SMALL_REGISTER_CLASSES - || 1 -#endif - ) - && MERGABLE_RELOADS (type, reload_when_needed[i], - opnum, reload_opnum[i])) - { - /* Make sure reload_in ultimately has the increment, - not the plain register. */ - if (GET_CODE (in) == REG) - in = reload_in[i]; - break; - } - - if (i == n_reloads) - { -#ifdef HAVE_SECONDARY_RELOADS - enum reg_class secondary_class = NO_REGS; - enum reg_class secondary_out_class = NO_REGS; - enum machine_mode secondary_mode = inmode; - enum machine_mode secondary_out_mode = outmode; - enum insn_code secondary_icode; - enum insn_code secondary_out_icode = CODE_FOR_nothing; - enum reg_class tertiary_class = NO_REGS; - enum reg_class tertiary_out_class = NO_REGS; - enum machine_mode tertiary_mode; - enum machine_mode tertiary_out_mode; - enum insn_code tertiary_icode; - enum insn_code tertiary_out_icode = CODE_FOR_nothing; - int tertiary_reload = -1; - - /* See if we need a secondary reload register to move between - CLASS and IN or CLASS and OUT. Get the modes and icodes to - use for each of them if so. */ - -#ifdef SECONDARY_INPUT_RELOAD_CLASS - if (in != 0) - secondary_class - = find_secondary_reload (in, class, inmode, 1, &secondary_icode, - &secondary_mode, &tertiary_class, - &tertiary_icode, &tertiary_mode); -#endif - -#ifdef SECONDARY_OUTPUT_RELOAD_CLASS - if (out != 0 && GET_CODE (out) != SCRATCH) - secondary_out_class - = find_secondary_reload (out, class, outmode, 0, - &secondary_out_icode, &secondary_out_mode, - &tertiary_out_class, &tertiary_out_icode, - &tertiary_out_mode); -#endif - - /* We can only record one secondary and one tertiary reload. If both - IN and OUT need secondary reloads, we can only make an in-out - reload if neither need an insn and if the classes are compatible. - If they aren't, all we can do is abort since making two separate - reloads is invalid. */ - - if (secondary_class != NO_REGS && secondary_out_class != NO_REGS - && reg_class_subset_p (secondary_out_class, secondary_class)) - secondary_class = secondary_out_class; - - if (secondary_class != NO_REGS && secondary_out_class != NO_REGS - && (! reg_class_subset_p (secondary_class, secondary_out_class) - || secondary_icode != CODE_FOR_nothing - || secondary_out_icode != CODE_FOR_nothing)) - abort (); - - /* If we need a secondary reload for OUT but not IN, copy the - information. */ - if (secondary_class == NO_REGS && secondary_out_class != NO_REGS) - { - secondary_class = secondary_out_class; - secondary_icode = secondary_out_icode; - tertiary_class = tertiary_out_class; - tertiary_icode = tertiary_out_icode; - tertiary_mode = tertiary_out_mode; - } - - if (secondary_class != NO_REGS) - { - /* Secondary reloads don't conflict as badly as the primary object - being reload. Specifically, we can always treat them as - being for an input or output address and hence allowed to be - reused in the same manner such address components could be - reused. This is used as the reload_type for our secondary - reloads. */ - - enum reload_type secondary_type - = (type == RELOAD_FOR_INPUT ? RELOAD_FOR_INPUT_ADDRESS - : type == RELOAD_FOR_OUTPUT ? RELOAD_FOR_OUTPUT_ADDRESS - : type); - - /* If we need a tertiary reload, see if we have one we can reuse - or else make one. */ - - if (tertiary_class != NO_REGS) - { - for (tertiary_reload = 0; tertiary_reload < n_reloads; - tertiary_reload++) - if (reload_secondary_p[tertiary_reload] - && (reg_class_subset_p (tertiary_class, - reload_reg_class[tertiary_reload]) - || reg_class_subset_p (reload_reg_class[tertiary_reload], - tertiary_class)) - && ((reload_inmode[tertiary_reload] == tertiary_mode) - || reload_inmode[tertiary_reload] == VOIDmode) - && ((reload_outmode[tertiary_reload] == tertiary_mode) - || reload_outmode[tertiary_reload] == VOIDmode) - && (reload_secondary_icode[tertiary_reload] - == CODE_FOR_nothing) - && (reg_class_size[(int) tertiary_class] == 1 -#ifdef SMALL_REGISTER_CLASSES - || 1 -#endif - ) - && MERGABLE_RELOADS (secondary_type, - reload_when_needed[tertiary_reload], - opnum, reload_opnum[tertiary_reload])) - { - if (tertiary_mode != VOIDmode) - reload_inmode[tertiary_reload] = tertiary_mode; - if (tertiary_out_mode != VOIDmode) - reload_outmode[tertiary_reload] = tertiary_mode; - if (reg_class_subset_p (tertiary_class, - reload_reg_class[tertiary_reload])) - reload_reg_class[tertiary_reload] = tertiary_class; - if (MERGE_TO_OTHER (secondary_type, - reload_when_needed[tertiary_reload], - opnum, - reload_opnum[tertiary_reload])) - reload_when_needed[tertiary_reload] = RELOAD_OTHER; - reload_opnum[tertiary_reload] - = MIN (reload_opnum[tertiary_reload], opnum); - reload_optional[tertiary_reload] &= optional; - reload_secondary_p[tertiary_reload] = 1; - } - - if (tertiary_reload == n_reloads) - { - /* We need to make a new tertiary reload for this register - class. */ - reload_in[tertiary_reload] = reload_out[tertiary_reload] = 0; - reload_reg_class[tertiary_reload] = tertiary_class; - reload_inmode[tertiary_reload] = tertiary_mode; - reload_outmode[tertiary_reload] = tertiary_mode; - reload_reg_rtx[tertiary_reload] = 0; - reload_optional[tertiary_reload] = optional; - reload_inc[tertiary_reload] = 0; - /* Maybe we could combine these, but it seems too tricky. */ - reload_nocombine[tertiary_reload] = 1; - reload_in_reg[tertiary_reload] = 0; - reload_opnum[tertiary_reload] = opnum; - reload_when_needed[tertiary_reload] = secondary_type; - reload_secondary_reload[tertiary_reload] = -1; - reload_secondary_icode[tertiary_reload] = CODE_FOR_nothing; - reload_secondary_p[tertiary_reload] = 1; - - n_reloads++; - i = n_reloads; - } - } - - /* See if we can reuse an existing secondary reload. */ - for (secondary_reload = 0; secondary_reload < n_reloads; - secondary_reload++) - if (reload_secondary_p[secondary_reload] - && (reg_class_subset_p (secondary_class, - reload_reg_class[secondary_reload]) - || reg_class_subset_p (reload_reg_class[secondary_reload], - secondary_class)) - && ((reload_inmode[secondary_reload] == secondary_mode) - || reload_inmode[secondary_reload] == VOIDmode) - && ((reload_outmode[secondary_reload] == secondary_out_mode) - || reload_outmode[secondary_reload] == VOIDmode) - && reload_secondary_reload[secondary_reload] == tertiary_reload - && reload_secondary_icode[secondary_reload] == tertiary_icode - && (reg_class_size[(int) secondary_class] == 1 -#ifdef SMALL_REGISTER_CLASSES - || 1 -#endif - ) - && MERGABLE_RELOADS (secondary_type, - reload_when_needed[secondary_reload], - opnum, reload_opnum[secondary_reload])) - { - if (secondary_mode != VOIDmode) - reload_inmode[secondary_reload] = secondary_mode; - if (secondary_out_mode != VOIDmode) - reload_outmode[secondary_reload] = secondary_out_mode; - if (reg_class_subset_p (secondary_class, - reload_reg_class[secondary_reload])) - reload_reg_class[secondary_reload] = secondary_class; - if (MERGE_TO_OTHER (secondary_type, - reload_when_needed[secondary_reload], - opnum, reload_opnum[secondary_reload])) - reload_when_needed[secondary_reload] = RELOAD_OTHER; - reload_opnum[secondary_reload] - = MIN (reload_opnum[secondary_reload], opnum); - reload_optional[secondary_reload] &= optional; - reload_secondary_p[secondary_reload] = 1; - } - - if (secondary_reload == n_reloads) - { - /* We need to make a new secondary reload for this register - class. */ - reload_in[secondary_reload] = reload_out[secondary_reload] = 0; - reload_reg_class[secondary_reload] = secondary_class; - reload_inmode[secondary_reload] = secondary_mode; - reload_outmode[secondary_reload] = secondary_out_mode; - reload_reg_rtx[secondary_reload] = 0; - reload_optional[secondary_reload] = optional; - reload_inc[secondary_reload] = 0; - /* Maybe we could combine these, but it seems too tricky. */ - reload_nocombine[secondary_reload] = 1; - reload_in_reg[secondary_reload] = 0; - reload_opnum[secondary_reload] = opnum; - reload_when_needed[secondary_reload] = secondary_type; - reload_secondary_reload[secondary_reload] = tertiary_reload; - reload_secondary_icode[secondary_reload] = tertiary_icode; - reload_secondary_p[secondary_reload] = 1; - - n_reloads++; - i = n_reloads; - -#ifdef SECONDARY_MEMORY_NEEDED - /* If we need a memory location to copy between the two - reload regs, set it up now. */ - - if (in != 0 && secondary_icode == CODE_FOR_nothing - && SECONDARY_MEMORY_NEEDED (secondary_class, class, inmode)) - get_secondary_mem (in, inmode, opnum, type); - - if (out != 0 && secondary_icode == CODE_FOR_nothing - && SECONDARY_MEMORY_NEEDED (class, secondary_class, outmode)) - get_secondary_mem (out, outmode, opnum, type); -#endif - } - } -#endif - - /* We found no existing reload suitable for re-use. - So add an additional reload. */ - - reload_in[i] = in; - reload_out[i] = out; - reload_reg_class[i] = class; - reload_inmode[i] = inmode; - reload_outmode[i] = outmode; - reload_reg_rtx[i] = 0; - reload_optional[i] = optional; - reload_inc[i] = 0; - reload_nocombine[i] = 0; - reload_in_reg[i] = inloc ? *inloc : 0; - reload_opnum[i] = opnum; - reload_when_needed[i] = type; - reload_secondary_reload[i] = secondary_reload; - reload_secondary_icode[i] = secondary_icode; - reload_secondary_p[i] = 0; - - n_reloads++; - -#ifdef SECONDARY_MEMORY_NEEDED - /* If a memory location is needed for the copy, make one. */ - if (in != 0 && GET_CODE (in) == REG - && REGNO (in) < FIRST_PSEUDO_REGISTER - && SECONDARY_MEMORY_NEEDED (REGNO_REG_CLASS (REGNO (in)), - class, inmode)) - get_secondary_mem (in, inmode, opnum, type); - - if (out != 0 && GET_CODE (out) == REG - && REGNO (out) < FIRST_PSEUDO_REGISTER - && SECONDARY_MEMORY_NEEDED (class, REGNO_REG_CLASS (REGNO (out)), - outmode)) - get_secondary_mem (out, outmode, opnum, type); -#endif - } - else - { - /* We are reusing an existing reload, - but we may have additional information for it. - For example, we may now have both IN and OUT - while the old one may have just one of them. */ - - if (inmode != VOIDmode) - reload_inmode[i] = inmode; - if (outmode != VOIDmode) - reload_outmode[i] = outmode; - if (in != 0) - reload_in[i] = in; - if (out != 0) - reload_out[i] = out; - if (reg_class_subset_p (class, reload_reg_class[i])) - reload_reg_class[i] = class; - reload_optional[i] &= optional; - if (MERGE_TO_OTHER (type, reload_when_needed[i], - opnum, reload_opnum[i])) - reload_when_needed[i] = RELOAD_OTHER; - reload_opnum[i] = MIN (reload_opnum[i], opnum); - } - - /* If the ostensible rtx being reload differs from the rtx found - in the location to substitute, this reload is not safe to combine - because we cannot reliably tell whether it appears in the insn. */ - - if (in != 0 && in != *inloc) - reload_nocombine[i] = 1; - -#if 0 - /* This was replaced by changes in find_reloads_address_1 and the new - function inc_for_reload, which go with a new meaning of reload_inc. */ - - /* If this is an IN/OUT reload in an insn that sets the CC, - it must be for an autoincrement. It doesn't work to store - the incremented value after the insn because that would clobber the CC. - So we must do the increment of the value reloaded from, - increment it, store it back, then decrement again. */ - if (out != 0 && sets_cc0_p (PATTERN (this_insn))) - { - out = 0; - reload_out[i] = 0; - reload_inc[i] = find_inc_amount (PATTERN (this_insn), in); - /* If we did not find a nonzero amount-to-increment-by, - that contradicts the belief that IN is being incremented - in an address in this insn. */ - if (reload_inc[i] == 0) - abort (); - } -#endif - - /* If we will replace IN and OUT with the reload-reg, - record where they are located so that substitution need - not do a tree walk. */ - - if (replace_reloads) - { - if (inloc != 0) - { - register struct replacement *r = &replacements[n_replacements++]; - r->what = i; - r->subreg_loc = in_subreg_loc; - r->where = inloc; - r->mode = inmode; - } - if (outloc != 0 && outloc != inloc) - { - register struct replacement *r = &replacements[n_replacements++]; - r->what = i; - r->where = outloc; - r->subreg_loc = out_subreg_loc; - r->mode = outmode; - } - } - - /* If this reload is just being introduced and it has both - an incoming quantity and an outgoing quantity that are - supposed to be made to match, see if either one of the two - can serve as the place to reload into. - - If one of them is acceptable, set reload_reg_rtx[i] - to that one. */ - - if (in != 0 && out != 0 && in != out && reload_reg_rtx[i] == 0) - { - reload_reg_rtx[i] = find_dummy_reload (in, out, inloc, outloc, - reload_reg_class[i], i); - - /* If the outgoing register already contains the same value - as the incoming one, we can dispense with loading it. - The easiest way to tell the caller that is to give a phony - value for the incoming operand (same as outgoing one). */ - if (reload_reg_rtx[i] == out - && (GET_CODE (in) == REG || CONSTANT_P (in)) - && 0 != find_equiv_reg (in, this_insn, 0, REGNO (out), - static_reload_reg_p, i, inmode)) - reload_in[i] = out; - } - - /* If this is an input reload and the operand contains a register that - dies in this insn and is used nowhere else, see if it is the right class - to be used for this reload. Use it if so. (This occurs most commonly - in the case of paradoxical SUBREGs and in-out reloads). We cannot do - this if it is also an output reload that mentions the register unless - the output is a SUBREG that clobbers an entire register. - - Note that the operand might be one of the spill regs, if it is a - pseudo reg and we are in a block where spilling has not taken place. - But if there is no spilling in this block, that is OK. - An explicitly used hard reg cannot be a spill reg. */ - - if (reload_reg_rtx[i] == 0 && in != 0) - { - rtx note; - int regno; - - for (note = REG_NOTES (this_insn); note; note = XEXP (note, 1)) - if (REG_NOTE_KIND (note) == REG_DEAD - && GET_CODE (XEXP (note, 0)) == REG - && (regno = REGNO (XEXP (note, 0))) < FIRST_PSEUDO_REGISTER - && reg_mentioned_p (XEXP (note, 0), in) - && ! refers_to_regno_for_reload_p (regno, - (regno - + HARD_REGNO_NREGS (regno, - inmode)), - PATTERN (this_insn), inloc) - /* If this is also an output reload, IN cannot be used as - the reload register if it is set in this insn unless IN - is also OUT. */ - && (out == 0 || in == out - || ! hard_reg_set_here_p (regno, - (regno - + HARD_REGNO_NREGS (regno, - inmode)), - PATTERN (this_insn))) - /* ??? Why is this code so different from the previous? - Is there any simple coherent way to describe the two together? - What's going on here. */ - && (in != out - || (GET_CODE (in) == SUBREG - && (((GET_MODE_SIZE (GET_MODE (in)) + (UNITS_PER_WORD - 1)) - / UNITS_PER_WORD) - == ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) - + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)))) - /* Make sure the operand fits in the reg that dies. */ - && GET_MODE_SIZE (inmode) <= GET_MODE_SIZE (GET_MODE (XEXP (note, 0))) - && HARD_REGNO_MODE_OK (regno, inmode) - && GET_MODE_SIZE (outmode) <= GET_MODE_SIZE (GET_MODE (XEXP (note, 0))) - && HARD_REGNO_MODE_OK (regno, outmode) - && TEST_HARD_REG_BIT (reg_class_contents[(int) class], regno) - && !fixed_regs[regno]) - { - reload_reg_rtx[i] = gen_rtx (REG, inmode, regno); - break; - } - } - - if (out) - output_reloadnum = i; - - return i; -} - -/* Record an additional place we must replace a value - for which we have already recorded a reload. - RELOADNUM is the value returned by push_reload - when the reload was recorded. - This is used in insn patterns that use match_dup. */ - -static void -push_replacement (loc, reloadnum, mode) - rtx *loc; - int reloadnum; - enum machine_mode mode; -{ - if (replace_reloads) - { - register struct replacement *r = &replacements[n_replacements++]; - r->what = reloadnum; - r->where = loc; - r->subreg_loc = 0; - r->mode = mode; - } -} - -/* Transfer all replacements that used to be in reload FROM to be in - reload TO. */ - -void -transfer_replacements (to, from) - int to, from; -{ - int i; - - for (i = 0; i < n_replacements; i++) - if (replacements[i].what == from) - replacements[i].what = to; -} - -/* If there is only one output reload, and it is not for an earlyclobber - operand, try to combine it with a (logically unrelated) input reload - to reduce the number of reload registers needed. - - This is safe if the input reload does not appear in - the value being output-reloaded, because this implies - it is not needed any more once the original insn completes. - - If that doesn't work, see we can use any of the registers that - die in this insn as a reload register. We can if it is of the right - class and does not appear in the value being output-reloaded. */ - -static void -combine_reloads () -{ - int i; - int output_reload = -1; - rtx note; - - /* Find the output reload; return unless there is exactly one - and that one is mandatory. */ - - for (i = 0; i < n_reloads; i++) - if (reload_out[i] != 0) - { - if (output_reload >= 0) - return; - output_reload = i; - } - - if (output_reload < 0 || reload_optional[output_reload]) - return; - - /* An input-output reload isn't combinable. */ - - if (reload_in[output_reload] != 0) - return; - - /* If this reload is for an earlyclobber operand, we can't do anything. */ - - for (i = 0; i < n_earlyclobbers; i++) - if (reload_out[output_reload] == reload_earlyclobbers[i]) - return; - - /* Check each input reload; can we combine it? */ - - for (i = 0; i < n_reloads; i++) - if (reload_in[i] && ! reload_optional[i] && ! reload_nocombine[i] - /* Life span of this reload must not extend past main insn. */ - && reload_when_needed[i] != RELOAD_FOR_OUTPUT_ADDRESS - && reload_when_needed[i] != RELOAD_OTHER - && (CLASS_MAX_NREGS (reload_reg_class[i], reload_inmode[i]) - == CLASS_MAX_NREGS (reload_reg_class[output_reload], - reload_outmode[output_reload])) - && reload_inc[i] == 0 - && reload_reg_rtx[i] == 0 - /* Don't combine two reloads with different secondary reloads. */ - && (reload_secondary_reload[i] == reload_secondary_reload[output_reload] - || reload_secondary_reload[i] == -1 - || reload_secondary_reload[output_reload] == -1) -#ifdef SECONDARY_MEMORY_NEEDED - /* Likewise for different secondary memory locations. */ - && (secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[i]] == 0 - || secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[output_reload]] == 0 - || rtx_equal_p (secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[i]], - secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[output_reload]])) -#endif -#ifdef SMALL_REGISTER_CLASSES - && reload_reg_class[i] == reload_reg_class[output_reload] -#else - && (reg_class_subset_p (reload_reg_class[i], - reload_reg_class[output_reload]) - || reg_class_subset_p (reload_reg_class[output_reload], - reload_reg_class[i])) -#endif - && (MATCHES (reload_in[i], reload_out[output_reload]) - /* Args reversed because the first arg seems to be - the one that we imagine being modified - while the second is the one that might be affected. */ - || (! reg_overlap_mentioned_for_reload_p (reload_out[output_reload], - reload_in[i]) - /* However, if the input is a register that appears inside - the output, then we also can't share. - Imagine (set (mem (reg 69)) (plus (reg 69) ...)). - If the same reload reg is used for both reg 69 and the - result to be stored in memory, then that result - will clobber the address of the memory ref. */ - && ! (GET_CODE (reload_in[i]) == REG - && reg_overlap_mentioned_for_reload_p (reload_in[i], - reload_out[output_reload])))) - && (reg_class_size[(int) reload_reg_class[i]] -#ifdef SMALL_REGISTER_CLASSES - || 1 -#endif - ) - /* We will allow making things slightly worse by combining an - input and an output, but no worse than that. */ - && (reload_when_needed[i] == RELOAD_FOR_INPUT - || reload_when_needed[i] == RELOAD_FOR_OUTPUT)) - { - int j; - - /* We have found a reload to combine with! */ - reload_out[i] = reload_out[output_reload]; - reload_outmode[i] = reload_outmode[output_reload]; - /* Mark the old output reload as inoperative. */ - reload_out[output_reload] = 0; - /* The combined reload is needed for the entire insn. */ - reload_when_needed[i] = RELOAD_OTHER; - /* If the output reload had a secondary reload, copy it. */ - if (reload_secondary_reload[output_reload] != -1) - reload_secondary_reload[i] = reload_secondary_reload[output_reload]; -#ifdef SECONDARY_MEMORY_NEEDED - /* Copy any secondary MEM. */ - if (secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[output_reload]] != 0) - secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[i]] - = secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[output_reload]]; -#endif - /* If required, minimize the register class. */ - if (reg_class_subset_p (reload_reg_class[output_reload], - reload_reg_class[i])) - reload_reg_class[i] = reload_reg_class[output_reload]; - - /* Transfer all replacements from the old reload to the combined. */ - for (j = 0; j < n_replacements; j++) - if (replacements[j].what == output_reload) - replacements[j].what = i; - - return; - } - - /* If this insn has only one operand that is modified or written (assumed - to be the first), it must be the one corresponding to this reload. It - is safe to use anything that dies in this insn for that output provided - that it does not occur in the output (we already know it isn't an - earlyclobber. If this is an asm insn, give up. */ - - if (INSN_CODE (this_insn) == -1) - return; - - for (i = 1; i < insn_n_operands[INSN_CODE (this_insn)]; i++) - if (insn_operand_constraint[INSN_CODE (this_insn)][i][0] == '=' - || insn_operand_constraint[INSN_CODE (this_insn)][i][0] == '+') - return; - - /* See if some hard register that dies in this insn and is not used in - the output is the right class. Only works if the register we pick - up can fully hold our output reload. */ - for (note = REG_NOTES (this_insn); note; note = XEXP (note, 1)) - if (REG_NOTE_KIND (note) == REG_DEAD - && GET_CODE (XEXP (note, 0)) == REG - && ! reg_overlap_mentioned_for_reload_p (XEXP (note, 0), - reload_out[output_reload]) - && REGNO (XEXP (note, 0)) < FIRST_PSEUDO_REGISTER - && HARD_REGNO_MODE_OK (REGNO (XEXP (note, 0)), reload_outmode[output_reload]) - && TEST_HARD_REG_BIT (reg_class_contents[(int) reload_reg_class[output_reload]], - REGNO (XEXP (note, 0))) - && (HARD_REGNO_NREGS (REGNO (XEXP (note, 0)), reload_outmode[output_reload]) - <= HARD_REGNO_NREGS (REGNO (XEXP (note, 0)), GET_MODE (XEXP (note, 0)))) - && ! fixed_regs[REGNO (XEXP (note, 0))]) - { - reload_reg_rtx[output_reload] = gen_rtx (REG, - reload_outmode[output_reload], - REGNO (XEXP (note, 0))); - return; - } -} - -/* Try to find a reload register for an in-out reload (expressions IN and OUT). - See if one of IN and OUT is a register that may be used; - this is desirable since a spill-register won't be needed. - If so, return the register rtx that proves acceptable. - - INLOC and OUTLOC are locations where IN and OUT appear in the insn. - CLASS is the register class required for the reload. - - If FOR_REAL is >= 0, it is the number of the reload, - and in some cases when it can be discovered that OUT doesn't need - to be computed, clear out reload_out[FOR_REAL]. - - If FOR_REAL is -1, this should not be done, because this call - is just to see if a register can be found, not to find and install it. */ - -static rtx -find_dummy_reload (real_in, real_out, inloc, outloc, class, for_real) - rtx real_in, real_out; - rtx *inloc, *outloc; - enum reg_class class; - int for_real; -{ - rtx in = real_in; - rtx out = real_out; - int in_offset = 0; - int out_offset = 0; - rtx value = 0; - - /* If operands exceed a word, we can't use either of them - unless they have the same size. */ - if (GET_MODE_SIZE (GET_MODE (real_out)) != GET_MODE_SIZE (GET_MODE (real_in)) - && (GET_MODE_SIZE (GET_MODE (real_out)) > UNITS_PER_WORD - || GET_MODE_SIZE (GET_MODE (real_in)) > UNITS_PER_WORD)) - return 0; - - /* Find the inside of any subregs. */ - while (GET_CODE (out) == SUBREG) - { - out_offset = SUBREG_WORD (out); - out = SUBREG_REG (out); - } - while (GET_CODE (in) == SUBREG) - { - in_offset = SUBREG_WORD (in); - in = SUBREG_REG (in); - } - - /* Narrow down the reg class, the same way push_reload will; - otherwise we might find a dummy now, but push_reload won't. */ - class = PREFERRED_RELOAD_CLASS (in, class); - - /* See if OUT will do. */ - if (GET_CODE (out) == REG - && REGNO (out) < FIRST_PSEUDO_REGISTER) - { - register int regno = REGNO (out) + out_offset; - int nwords = HARD_REGNO_NREGS (regno, GET_MODE (real_out)); - rtx saved_rtx; - - /* When we consider whether the insn uses OUT, - ignore references within IN. They don't prevent us - from copying IN into OUT, because those refs would - move into the insn that reloads IN. - - However, we only ignore IN in its role as this reload. - If the insn uses IN elsewhere and it contains OUT, - that counts. We can't be sure it's the "same" operand - so it might not go through this reload. */ - saved_rtx = *inloc; - *inloc = const0_rtx; - - if (regno < FIRST_PSEUDO_REGISTER - /* A fixed reg that can overlap other regs better not be used - for reloading in any way. */ -#ifdef OVERLAPPING_REGNO_P - && ! (fixed_regs[regno] && OVERLAPPING_REGNO_P (regno)) -#endif - && ! refers_to_regno_for_reload_p (regno, regno + nwords, - PATTERN (this_insn), outloc)) - { - int i; - for (i = 0; i < nwords; i++) - if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], - regno + i)) - break; - - if (i == nwords) - { - if (GET_CODE (real_out) == REG) - value = real_out; - else - value = gen_rtx (REG, GET_MODE (real_out), regno); - } - } - - *inloc = saved_rtx; - } - - /* Consider using IN if OUT was not acceptable - or if OUT dies in this insn (like the quotient in a divmod insn). - We can't use IN unless it is dies in this insn, - which means we must know accurately which hard regs are live. - Also, the result can't go in IN if IN is used within OUT. */ - if (hard_regs_live_known - && GET_CODE (in) == REG - && REGNO (in) < FIRST_PSEUDO_REGISTER - && (value == 0 - || find_reg_note (this_insn, REG_UNUSED, real_out)) - && find_reg_note (this_insn, REG_DEAD, real_in) - && !fixed_regs[REGNO (in)] - && HARD_REGNO_MODE_OK (REGNO (in), GET_MODE (out))) - { - register int regno = REGNO (in) + in_offset; - int nwords = HARD_REGNO_NREGS (regno, GET_MODE (real_in)); - - if (! refers_to_regno_for_reload_p (regno, regno + nwords, out, NULL_PTR) - && ! hard_reg_set_here_p (regno, regno + nwords, - PATTERN (this_insn))) - { - int i; - for (i = 0; i < nwords; i++) - if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], - regno + i)) - break; - - if (i == nwords) - { - /* If we were going to use OUT as the reload reg - and changed our mind, it means OUT is a dummy that - dies here. So don't bother copying value to it. */ - if (for_real >= 0 && value == real_out) - reload_out[for_real] = 0; - if (GET_CODE (real_in) == REG) - value = real_in; - else - value = gen_rtx (REG, GET_MODE (real_in), regno); - } - } - } - - return value; -} - -/* This page contains subroutines used mainly for determining - whether the IN or an OUT of a reload can serve as the - reload register. */ - -/* Return 1 if expression X alters a hard reg in the range - from BEG_REGNO (inclusive) to END_REGNO (exclusive), - either explicitly or in the guise of a pseudo-reg allocated to REGNO. - X should be the body of an instruction. */ - -static int -hard_reg_set_here_p (beg_regno, end_regno, x) - register int beg_regno, end_regno; - rtx x; -{ - if (GET_CODE (x) == SET || GET_CODE (x) == CLOBBER) - { - register rtx op0 = SET_DEST (x); - while (GET_CODE (op0) == SUBREG) - op0 = SUBREG_REG (op0); - if (GET_CODE (op0) == REG) - { - register int r = REGNO (op0); - /* See if this reg overlaps range under consideration. */ - if (r < end_regno - && r + HARD_REGNO_NREGS (r, GET_MODE (op0)) > beg_regno) - return 1; - } - } - else if (GET_CODE (x) == PARALLEL) - { - register int i = XVECLEN (x, 0) - 1; - for (; i >= 0; i--) - if (hard_reg_set_here_p (beg_regno, end_regno, XVECEXP (x, 0, i))) - return 1; - } - - return 0; -} - -/* Return 1 if ADDR is a valid memory address for mode MODE, - and check that each pseudo reg has the proper kind of - hard reg. */ - -int -strict_memory_address_p (mode, addr) - enum machine_mode mode; - register rtx addr; -{ - GO_IF_LEGITIMATE_ADDRESS (mode, addr, win); - return 0; - - win: - return 1; -} - -/* Like rtx_equal_p except that it allows a REG and a SUBREG to match - if they are the same hard reg, and has special hacks for - autoincrement and autodecrement. - This is specifically intended for find_reloads to use - in determining whether two operands match. - X is the operand whose number is the lower of the two. - - The value is 2 if Y contains a pre-increment that matches - a non-incrementing address in X. */ - -/* ??? To be completely correct, we should arrange to pass - for X the output operand and for Y the input operand. - For now, we assume that the output operand has the lower number - because that is natural in (SET output (... input ...)). */ - -int -operands_match_p (x, y) - register rtx x, y; -{ - register int i; - register RTX_CODE code = GET_CODE (x); - register char *fmt; - int success_2; - - if (x == y) - return 1; - if ((code == REG || (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG)) - && (GET_CODE (y) == REG || (GET_CODE (y) == SUBREG - && GET_CODE (SUBREG_REG (y)) == REG))) - { - register int j; - - if (code == SUBREG) - { - i = REGNO (SUBREG_REG (x)); - if (i >= FIRST_PSEUDO_REGISTER) - goto slow; - i += SUBREG_WORD (x); - } - else - i = REGNO (x); - - if (GET_CODE (y) == SUBREG) - { - j = REGNO (SUBREG_REG (y)); - if (j >= FIRST_PSEUDO_REGISTER) - goto slow; - j += SUBREG_WORD (y); - } - else - j = REGNO (y); - - /* On a WORDS_BIG_ENDIAN machine, point to the last register of a - multiple hard register group, so that for example (reg:DI 0) and - (reg:SI 1) will be considered the same register. */ - if (WORDS_BIG_ENDIAN && GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD - && i < FIRST_PSEUDO_REGISTER) - i += (GET_MODE_SIZE (GET_MODE (x)) / UNITS_PER_WORD) - 1; - if (WORDS_BIG_ENDIAN && GET_MODE_SIZE (GET_MODE (y)) > UNITS_PER_WORD - && j < FIRST_PSEUDO_REGISTER) - j += (GET_MODE_SIZE (GET_MODE (y)) / UNITS_PER_WORD) - 1; - - return i == j; - } - /* If two operands must match, because they are really a single - operand of an assembler insn, then two postincrements are invalid - because the assembler insn would increment only once. - On the other hand, an postincrement matches ordinary indexing - if the postincrement is the output operand. */ - if (code == POST_DEC || code == POST_INC) - return operands_match_p (XEXP (x, 0), y); - /* Two preincrements are invalid - because the assembler insn would increment only once. - On the other hand, an preincrement matches ordinary indexing - if the preincrement is the input operand. - In this case, return 2, since some callers need to do special - things when this happens. */ - if (GET_CODE (y) == PRE_DEC || GET_CODE (y) == PRE_INC) - return operands_match_p (x, XEXP (y, 0)) ? 2 : 0; - - slow: - - /* Now we have disposed of all the cases - in which different rtx codes can match. */ - if (code != GET_CODE (y)) - return 0; - if (code == LABEL_REF) - return XEXP (x, 0) == XEXP (y, 0); - if (code == SYMBOL_REF) - return XSTR (x, 0) == XSTR (y, 0); - - /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */ - - if (GET_MODE (x) != GET_MODE (y)) - return 0; - - /* Compare the elements. If any pair of corresponding elements - fail to match, return 0 for the whole things. */ - - success_2 = 0; - fmt = GET_RTX_FORMAT (code); - for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - { - int val; - switch (fmt[i]) - { - case 'w': - if (XWINT (x, i) != XWINT (y, i)) - return 0; - break; - - case 'i': - if (XINT (x, i) != XINT (y, i)) - return 0; - break; - - case 'e': - val = operands_match_p (XEXP (x, i), XEXP (y, i)); - if (val == 0) - return 0; - /* If any subexpression returns 2, - we should return 2 if we are successful. */ - if (val == 2) - success_2 = 1; - break; - - case '0': - break; - - /* It is believed that rtx's at this level will never - contain anything but integers and other rtx's, - except for within LABEL_REFs and SYMBOL_REFs. */ - default: - abort (); - } - } - return 1 + success_2; -} - -/* Return the number of times character C occurs in string S. */ - -int -n_occurrences (c, s) - char c; - char *s; -{ - int n = 0; - while (*s) - n += (*s++ == c); - return n; -} - -/* Describe the range of registers or memory referenced by X. - If X is a register, set REG_FLAG and put the first register - number into START and the last plus one into END. - If X is a memory reference, put a base address into BASE - and a range of integer offsets into START and END. - If X is pushing on the stack, we can assume it causes no trouble, - so we set the SAFE field. */ - -static struct decomposition -decompose (x) - rtx x; -{ - struct decomposition val; - int all_const = 0; - - val.reg_flag = 0; - val.safe = 0; - if (GET_CODE (x) == MEM) - { - rtx base, offset = 0; - rtx addr = XEXP (x, 0); - - if (GET_CODE (addr) == PRE_DEC || GET_CODE (addr) == PRE_INC - || GET_CODE (addr) == POST_DEC || GET_CODE (addr) == POST_INC) - { - val.base = XEXP (addr, 0); - val.start = - GET_MODE_SIZE (GET_MODE (x)); - val.end = GET_MODE_SIZE (GET_MODE (x)); - val.safe = REGNO (val.base) == STACK_POINTER_REGNUM; - return val; - } - - if (GET_CODE (addr) == CONST) - { - addr = XEXP (addr, 0); - all_const = 1; - } - if (GET_CODE (addr) == PLUS) - { - if (CONSTANT_P (XEXP (addr, 0))) - { - base = XEXP (addr, 1); - offset = XEXP (addr, 0); - } - else if (CONSTANT_P (XEXP (addr, 1))) - { - base = XEXP (addr, 0); - offset = XEXP (addr, 1); - } - } - - if (offset == 0) - { - base = addr; - offset = const0_rtx; - } - if (GET_CODE (offset) == CONST) - offset = XEXP (offset, 0); - if (GET_CODE (offset) == PLUS) - { - if (GET_CODE (XEXP (offset, 0)) == CONST_INT) - { - base = gen_rtx (PLUS, GET_MODE (base), base, XEXP (offset, 1)); - offset = XEXP (offset, 0); - } - else if (GET_CODE (XEXP (offset, 1)) == CONST_INT) - { - base = gen_rtx (PLUS, GET_MODE (base), base, XEXP (offset, 0)); - offset = XEXP (offset, 1); - } - else - { - base = gen_rtx (PLUS, GET_MODE (base), base, offset); - offset = const0_rtx; - } - } - else if (GET_CODE (offset) != CONST_INT) - { - base = gen_rtx (PLUS, GET_MODE (base), base, offset); - offset = const0_rtx; - } - - if (all_const && GET_CODE (base) == PLUS) - base = gen_rtx (CONST, GET_MODE (base), base); - - if (GET_CODE (offset) != CONST_INT) - abort (); - - val.start = INTVAL (offset); - val.end = val.start + GET_MODE_SIZE (GET_MODE (x)); - val.base = base; - return val; - } - else if (GET_CODE (x) == REG) - { - val.reg_flag = 1; - val.start = true_regnum (x); - if (val.start < 0) - { - /* A pseudo with no hard reg. */ - val.start = REGNO (x); - val.end = val.start + 1; - } - else - /* A hard reg. */ - val.end = val.start + HARD_REGNO_NREGS (val.start, GET_MODE (x)); - } - else if (GET_CODE (x) == SUBREG) - { - if (GET_CODE (SUBREG_REG (x)) != REG) - /* This could be more precise, but it's good enough. */ - return decompose (SUBREG_REG (x)); - val.reg_flag = 1; - val.start = true_regnum (x); - if (val.start < 0) - return decompose (SUBREG_REG (x)); - else - /* A hard reg. */ - val.end = val.start + HARD_REGNO_NREGS (val.start, GET_MODE (x)); - } - else if (CONSTANT_P (x) - /* This hasn't been assigned yet, so it can't conflict yet. */ - || GET_CODE (x) == SCRATCH) - val.safe = 1; - else - abort (); - return val; -} - -/* Return 1 if altering Y will not modify the value of X. - Y is also described by YDATA, which should be decompose (Y). */ - -static int -immune_p (x, y, ydata) - rtx x, y; - struct decomposition ydata; -{ - struct decomposition xdata; - - if (ydata.reg_flag) - return !refers_to_regno_for_reload_p (ydata.start, ydata.end, x, NULL_PTR); - if (ydata.safe) - return 1; - - if (GET_CODE (y) != MEM) - abort (); - /* If Y is memory and X is not, Y can't affect X. */ - if (GET_CODE (x) != MEM) - return 1; - - xdata = decompose (x); - - if (! rtx_equal_p (xdata.base, ydata.base)) - { - /* If bases are distinct symbolic constants, there is no overlap. */ - if (CONSTANT_P (xdata.base) && CONSTANT_P (ydata.base)) - return 1; - /* Constants and stack slots never overlap. */ - if (CONSTANT_P (xdata.base) - && (ydata.base == frame_pointer_rtx - || ydata.base == stack_pointer_rtx)) - return 1; - if (CONSTANT_P (ydata.base) - && (xdata.base == frame_pointer_rtx - || xdata.base == stack_pointer_rtx)) - return 1; - /* If either base is variable, we don't know anything. */ - return 0; - } - - - return (xdata.start >= ydata.end || ydata.start >= xdata.end); -} - -/* Similar, but calls decompose. */ - -int -safe_from_earlyclobber (op, clobber) - rtx op, clobber; -{ - struct decomposition early_data; - - early_data = decompose (clobber); - return immune_p (op, clobber, early_data); -} - -/* Main entry point of this file: search the body of INSN - for values that need reloading and record them with push_reload. - REPLACE nonzero means record also where the values occur - so that subst_reloads can be used. - - IND_LEVELS says how many levels of indirection are supported by this - machine; a value of zero means that a memory reference is not a valid - memory address. - - LIVE_KNOWN says we have valid information about which hard - regs are live at each point in the program; this is true when - we are called from global_alloc but false when stupid register - allocation has been done. - - RELOAD_REG_P if nonzero is a vector indexed by hard reg number - which is nonnegative if the reg has been commandeered for reloading into. - It is copied into STATIC_RELOAD_REG_P and referenced from there - by various subroutines. */ - -void -find_reloads (insn, replace, ind_levels, live_known, reload_reg_p) - rtx insn; - int replace, ind_levels; - int live_known; - short *reload_reg_p; -{ -#ifdef REGISTER_CONSTRAINTS - - register int insn_code_number; - register int i, j; - int noperands; - /* These are the constraints for the insn. We don't change them. */ - char *constraints1[MAX_RECOG_OPERANDS]; - /* These start out as the constraints for the insn - and they are chewed up as we consider alternatives. */ - char *constraints[MAX_RECOG_OPERANDS]; - /* These are the preferred classes for an operand, or NO_REGS if it isn't - a register. */ - enum reg_class preferred_class[MAX_RECOG_OPERANDS]; - char pref_or_nothing[MAX_RECOG_OPERANDS]; - /* Nonzero for a MEM operand whose entire address needs a reload. */ - int address_reloaded[MAX_RECOG_OPERANDS]; - /* Value of enum reload_type to use for operand. */ - enum reload_type operand_type[MAX_RECOG_OPERANDS]; - /* Value of enum reload_type to use within address of operand. */ - enum reload_type address_type[MAX_RECOG_OPERANDS]; - /* Save the usage of each operand. */ - enum reload_usage { RELOAD_READ, RELOAD_READ_WRITE, RELOAD_WRITE } modified[MAX_RECOG_OPERANDS]; - int no_input_reloads = 0, no_output_reloads = 0; - int n_alternatives; - int this_alternative[MAX_RECOG_OPERANDS]; - char this_alternative_win[MAX_RECOG_OPERANDS]; - char this_alternative_offmemok[MAX_RECOG_OPERANDS]; - char this_alternative_earlyclobber[MAX_RECOG_OPERANDS]; - int this_alternative_matches[MAX_RECOG_OPERANDS]; - int swapped; - int goal_alternative[MAX_RECOG_OPERANDS]; - int this_alternative_number; - int goal_alternative_number; - int operand_reloadnum[MAX_RECOG_OPERANDS]; - int goal_alternative_matches[MAX_RECOG_OPERANDS]; - int goal_alternative_matched[MAX_RECOG_OPERANDS]; - char goal_alternative_win[MAX_RECOG_OPERANDS]; - char goal_alternative_offmemok[MAX_RECOG_OPERANDS]; - char goal_alternative_earlyclobber[MAX_RECOG_OPERANDS]; - int goal_alternative_swapped; - int best; - int commutative; - char operands_match[MAX_RECOG_OPERANDS][MAX_RECOG_OPERANDS]; - rtx substed_operand[MAX_RECOG_OPERANDS]; - rtx body = PATTERN (insn); - rtx set = single_set (insn); - int goal_earlyclobber, this_earlyclobber; - enum machine_mode operand_mode[MAX_RECOG_OPERANDS]; - - this_insn = insn; - this_insn_is_asm = 0; /* Tentative. */ - n_reloads = 0; - n_replacements = 0; - n_memlocs = 0; - n_earlyclobbers = 0; - replace_reloads = replace; - hard_regs_live_known = live_known; - static_reload_reg_p = reload_reg_p; - - /* JUMP_INSNs and CALL_INSNs are not allowed to have any output reloads; - neither are insns that SET cc0. Insns that use CC0 are not allowed - to have any input reloads. */ - if (GET_CODE (insn) == JUMP_INSN || GET_CODE (insn) == CALL_INSN) - no_output_reloads = 1; - -#ifdef HAVE_cc0 - if (reg_referenced_p (cc0_rtx, PATTERN (insn))) - no_input_reloads = 1; - if (reg_set_p (cc0_rtx, PATTERN (insn))) - no_output_reloads = 1; -#endif - -#ifdef SECONDARY_MEMORY_NEEDED - /* The eliminated forms of any secondary memory locations are per-insn, so - clear them out here. */ - - bzero (secondary_memlocs_elim, sizeof secondary_memlocs_elim); -#endif - - /* Find what kind of insn this is. NOPERANDS gets number of operands. - Make OPERANDS point to a vector of operand values. - Make OPERAND_LOCS point to a vector of pointers to - where the operands were found. - Fill CONSTRAINTS and CONSTRAINTS1 with pointers to the - constraint-strings for this insn. - Return if the insn needs no reload processing. */ - - switch (GET_CODE (body)) - { - case USE: - case CLOBBER: - case ASM_INPUT: - case ADDR_VEC: - case ADDR_DIFF_VEC: - return; - - case SET: - /* Dispose quickly of (set (reg..) (reg..)) if both have hard regs and it - is cheap to move between them. If it is not, there may not be an insn - to do the copy, so we may need a reload. */ - if (GET_CODE (SET_DEST (body)) == REG - && REGNO (SET_DEST (body)) < FIRST_PSEUDO_REGISTER - && GET_CODE (SET_SRC (body)) == REG - && REGNO (SET_SRC (body)) < FIRST_PSEUDO_REGISTER - && REGISTER_MOVE_COST (REGNO_REG_CLASS (REGNO (SET_SRC (body))), - REGNO_REG_CLASS (REGNO (SET_DEST (body)))) == 2) - return; - case PARALLEL: - case ASM_OPERANDS: - reload_n_operands = noperands = asm_noperands (body); - if (noperands >= 0) - { - /* This insn is an `asm' with operands. */ - - insn_code_number = -1; - this_insn_is_asm = 1; - - /* expand_asm_operands makes sure there aren't too many operands. */ - if (noperands > MAX_RECOG_OPERANDS) - abort (); - - /* Now get the operand values and constraints out of the insn. */ - - decode_asm_operands (body, recog_operand, recog_operand_loc, - constraints, operand_mode); - if (noperands > 0) - { - bcopy (constraints, constraints1, noperands * sizeof (char *)); - n_alternatives = n_occurrences (',', constraints[0]) + 1; - for (i = 1; i < noperands; i++) - if (n_alternatives != n_occurrences (',', constraints[i]) + 1) - { - error_for_asm (insn, "operand constraints differ in number of alternatives"); - /* Avoid further trouble with this insn. */ - PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx); - n_reloads = 0; - return; - } - } - break; - } - - default: - /* Ordinary insn: recognize it, get the operands via insn_extract - and get the constraints. */ - - insn_code_number = recog_memoized (insn); - if (insn_code_number < 0) - fatal_insn_not_found (insn); - - reload_n_operands = noperands = insn_n_operands[insn_code_number]; - n_alternatives = insn_n_alternatives[insn_code_number]; - /* Just return "no reloads" if insn has no operands with constraints. */ - if (n_alternatives == 0) - return; - insn_extract (insn); - for (i = 0; i < noperands; i++) - { - constraints[i] = constraints1[i] - = insn_operand_constraint[insn_code_number][i]; - operand_mode[i] = insn_operand_mode[insn_code_number][i]; - } - } - - if (noperands == 0) - return; - - commutative = -1; - - /* If we will need to know, later, whether some pair of operands - are the same, we must compare them now and save the result. - Reloading the base and index registers will clobber them - and afterward they will fail to match. */ - - for (i = 0; i < noperands; i++) - { - register char *p; - register int c; - - substed_operand[i] = recog_operand[i]; - p = constraints[i]; - - modified[i] = RELOAD_READ; - - /* Scan this operand's constraint to see if it is an output operand, - an in-out operand, is commutative, or should match another. */ - - while (c = *p++) - { - if (c == '=') - modified[i] = RELOAD_WRITE; - else if (c == '+') - modified[i] = RELOAD_READ_WRITE; - else if (c == '%') - { - /* The last operand should not be marked commutative. */ - if (i == noperands - 1) - { - if (this_insn_is_asm) - warning_for_asm (this_insn, - "`%%' constraint used with last operand"); - else - abort (); - } - else - commutative = i; - } - else if (c >= '0' && c <= '9') - { - c -= '0'; - operands_match[c][i] - = operands_match_p (recog_operand[c], recog_operand[i]); - - /* An operand may not match itself. */ - if (c == i) - { - if (this_insn_is_asm) - warning_for_asm (this_insn, - "operand %d has constraint %d", i, c); - else - abort (); - } - - /* If C can be commuted with C+1, and C might need to match I, - then C+1 might also need to match I. */ - if (commutative >= 0) - { - if (c == commutative || c == commutative + 1) - { - int other = c + (c == commutative ? 1 : -1); - operands_match[other][i] - = operands_match_p (recog_operand[other], recog_operand[i]); - } - if (i == commutative || i == commutative + 1) - { - int other = i + (i == commutative ? 1 : -1); - operands_match[c][other] - = operands_match_p (recog_operand[c], recog_operand[other]); - } - /* Note that C is supposed to be less than I. - No need to consider altering both C and I because in - that case we would alter one into the other. */ - } - } - } - } - - /* Examine each operand that is a memory reference or memory address - and reload parts of the addresses into index registers. - Also here any references to pseudo regs that didn't get hard regs - but are equivalent to constants get replaced in the insn itself - with those constants. Nobody will ever see them again. - - Finally, set up the preferred classes of each operand. */ - - for (i = 0; i < noperands; i++) - { - register RTX_CODE code = GET_CODE (recog_operand[i]); - - address_reloaded[i] = 0; - operand_type[i] = (modified[i] == RELOAD_READ ? RELOAD_FOR_INPUT - : modified[i] == RELOAD_WRITE ? RELOAD_FOR_OUTPUT - : RELOAD_OTHER); - address_type[i] - = (modified[i] == RELOAD_READ ? RELOAD_FOR_INPUT_ADDRESS - : modified[i] == RELOAD_WRITE ? RELOAD_FOR_OUTPUT_ADDRESS - : RELOAD_OTHER); - - if (constraints[i][0] == 'p') - { - find_reloads_address (VOIDmode, NULL_PTR, - recog_operand[i], recog_operand_loc[i], - i, operand_type[i], ind_levels); - substed_operand[i] = recog_operand[i] = *recog_operand_loc[i]; - } - else if (code == MEM) - { - if (find_reloads_address (GET_MODE (recog_operand[i]), - recog_operand_loc[i], - XEXP (recog_operand[i], 0), - &XEXP (recog_operand[i], 0), - i, address_type[i], ind_levels)) - address_reloaded[i] = 1; - substed_operand[i] = recog_operand[i] = *recog_operand_loc[i]; - } - else if (code == SUBREG) - substed_operand[i] = recog_operand[i] = *recog_operand_loc[i] - = find_reloads_toplev (recog_operand[i], i, address_type[i], - ind_levels, - set != 0 - && &SET_DEST (set) == recog_operand_loc[i]); - else if (code == REG) - { - /* This is equivalent to calling find_reloads_toplev. - The code is duplicated for speed. - When we find a pseudo always equivalent to a constant, - we replace it by the constant. We must be sure, however, - that we don't try to replace it in the insn in which it - is being set. */ - register int regno = REGNO (recog_operand[i]); - if (reg_equiv_constant[regno] != 0 - && (set == 0 || &SET_DEST (set) != recog_operand_loc[i])) - substed_operand[i] = recog_operand[i] - = reg_equiv_constant[regno]; -#if 0 /* This might screw code in reload1.c to delete prior output-reload - that feeds this insn. */ - if (reg_equiv_mem[regno] != 0) - substed_operand[i] = recog_operand[i] - = reg_equiv_mem[regno]; -#endif - if (reg_equiv_address[regno] != 0) - { - /* If reg_equiv_address is not a constant address, copy it, - since it may be shared. */ - rtx address = reg_equiv_address[regno]; - - if (rtx_varies_p (address)) - address = copy_rtx (address); - - /* If this is an output operand, we must output a CLOBBER - after INSN so find_equiv_reg knows REGNO is being written. - Mark this insn specially, do we can put our output reloads - after it. */ - - if (modified[i] != RELOAD_READ) - PUT_MODE (emit_insn_after (gen_rtx (CLOBBER, VOIDmode, - recog_operand[i]), - insn), - DImode); - - *recog_operand_loc[i] = recog_operand[i] - = gen_rtx (MEM, GET_MODE (recog_operand[i]), address); - RTX_UNCHANGING_P (recog_operand[i]) - = RTX_UNCHANGING_P (regno_reg_rtx[regno]); - find_reloads_address (GET_MODE (recog_operand[i]), - recog_operand_loc[i], - XEXP (recog_operand[i], 0), - &XEXP (recog_operand[i], 0), - i, address_type[i], ind_levels); - substed_operand[i] = recog_operand[i] = *recog_operand_loc[i]; - } - } - /* If the operand is still a register (we didn't replace it with an - equivalent), get the preferred class to reload it into. */ - code = GET_CODE (recog_operand[i]); - preferred_class[i] - = ((code == REG && REGNO (recog_operand[i]) >= FIRST_PSEUDO_REGISTER) - ? reg_preferred_class (REGNO (recog_operand[i])) : NO_REGS); - pref_or_nothing[i] - = (code == REG && REGNO (recog_operand[i]) >= FIRST_PSEUDO_REGISTER - && reg_alternate_class (REGNO (recog_operand[i])) == NO_REGS); - } - - /* If this is simply a copy from operand 1 to operand 0, merge the - preferred classes for the operands. */ - if (set != 0 && noperands >= 2 && recog_operand[0] == SET_DEST (set) - && recog_operand[1] == SET_SRC (set)) - { - preferred_class[0] = preferred_class[1] - = reg_class_subunion[(int) preferred_class[0]][(int) preferred_class[1]]; - pref_or_nothing[0] |= pref_or_nothing[1]; - pref_or_nothing[1] |= pref_or_nothing[0]; - } - - /* Now see what we need for pseudo-regs that didn't get hard regs - or got the wrong kind of hard reg. For this, we must consider - all the operands together against the register constraints. */ - - best = MAX_RECOG_OPERANDS + 300; - - swapped = 0; - goal_alternative_swapped = 0; - try_swapped: - - /* The constraints are made of several alternatives. - Each operand's constraint looks like foo,bar,... with commas - separating the alternatives. The first alternatives for all - operands go together, the second alternatives go together, etc. - - First loop over alternatives. */ - - for (this_alternative_number = 0; - this_alternative_number < n_alternatives; - this_alternative_number++) - { - /* Loop over operands for one constraint alternative. */ - /* LOSERS counts those that don't fit this alternative - and would require loading. */ - int losers = 0; - /* BAD is set to 1 if it some operand can't fit this alternative - even after reloading. */ - int bad = 0; - /* REJECT is a count of how undesirable this alternative says it is - if any reloading is required. If the alternative matches exactly - then REJECT is ignored, but otherwise it gets this much - counted against it in addition to the reloading needed. Each - ? counts three times here since we want the disparaging caused by - a bad register class to only count 1/3 as much. */ - int reject = 0; - - this_earlyclobber = 0; - - for (i = 0; i < noperands; i++) - { - register char *p = constraints[i]; - register int win = 0; - /* 0 => this operand can be reloaded somehow for this alternative */ - int badop = 1; - /* 0 => this operand can be reloaded if the alternative allows regs. */ - int winreg = 0; - int c; - register rtx operand = recog_operand[i]; - int offset = 0; - /* Nonzero means this is a MEM that must be reloaded into a reg - regardless of what the constraint says. */ - int force_reload = 0; - int offmemok = 0; - int earlyclobber = 0; - - /* If the operand is a SUBREG, extract - the REG or MEM (or maybe even a constant) within. - (Constants can occur as a result of reg_equiv_constant.) */ - - while (GET_CODE (operand) == SUBREG) - { - offset += SUBREG_WORD (operand); - operand = SUBREG_REG (operand); - /* Force reload if this is not a register or if there may may - be a problem accessing the register in the outer mode. */ - if (GET_CODE (operand) != REG -#if defined(BYTE_LOADS_ZERO_EXTEND) || defined(BYTE_LOADS_SIGN_EXTEND) - /* ??? The comment below clearly does not match the code. - What the code below actually does is set force_reload - for a paradoxical subreg of a pseudo. rms and kenner - can't see the point of doing this. */ - /* Nonparadoxical subreg of a pseudoreg. - Don't to load the full width if on this machine - we expected the fetch to extend. */ - || ((GET_MODE_SIZE (operand_mode[i]) - > GET_MODE_SIZE (GET_MODE (operand))) - && REGNO (operand) >= FIRST_PSEUDO_REGISTER) -#endif - /* Subreg of a hard reg which can't handle the subreg's mode - or which would handle that mode in the wrong number of - registers for subregging to work. */ - || (REGNO (operand) < FIRST_PSEUDO_REGISTER - && (! HARD_REGNO_MODE_OK (REGNO (operand), - operand_mode[i]) - || (GET_MODE_SIZE (operand_mode[i]) <= UNITS_PER_WORD - && (GET_MODE_SIZE (GET_MODE (operand)) - > UNITS_PER_WORD) - && ((GET_MODE_SIZE (GET_MODE (operand)) - / UNITS_PER_WORD) - != HARD_REGNO_NREGS (REGNO (operand), - GET_MODE (operand))))))) - force_reload = 1; - } - - this_alternative[i] = (int) NO_REGS; - this_alternative_win[i] = 0; - this_alternative_offmemok[i] = 0; - this_alternative_earlyclobber[i] = 0; - this_alternative_matches[i] = -1; - - /* An empty constraint or empty alternative - allows anything which matched the pattern. */ - if (*p == 0 || *p == ',') - win = 1, badop = 0; - - /* Scan this alternative's specs for this operand; - set WIN if the operand fits any letter in this alternative. - Otherwise, clear BADOP if this operand could - fit some letter after reloads, - or set WINREG if this operand could fit after reloads - provided the constraint allows some registers. */ - - while (*p && (c = *p++) != ',') - switch (c) - { - case '=': - case '+': - case '*': - break; - - case '%': - /* The last operand should not be marked commutative. */ - if (i != noperands - 1) - commutative = i; - break; - - case '?': - reject += 3; - break; - - case '!': - reject = 300; - break; - - case '#': - /* Ignore rest of this alternative as far as - reloading is concerned. */ - while (*p && *p != ',') p++; - break; - - case '0': - case '1': - case '2': - case '3': - case '4': - c -= '0'; - this_alternative_matches[i] = c; - /* We are supposed to match a previous operand. - If we do, we win if that one did. - If we do not, count both of the operands as losers. - (This is too conservative, since most of the time - only a single reload insn will be needed to make - the two operands win. As a result, this alternative - may be rejected when it is actually desirable.) */ - if ((swapped && (c != commutative || i != commutative + 1)) - /* If we are matching as if two operands were swapped, - also pretend that operands_match had been computed - with swapped. - But if I is the second of those and C is the first, - don't exchange them, because operands_match is valid - only on one side of its diagonal. */ - ? (operands_match - [(c == commutative || c == commutative + 1) - ? 2*commutative + 1 - c : c] - [(i == commutative || i == commutative + 1) - ? 2*commutative + 1 - i : i]) - : operands_match[c][i]) - win = this_alternative_win[c]; - else - { - /* Operands don't match. */ - rtx value; - /* Retroactively mark the operand we had to match - as a loser, if it wasn't already. */ - if (this_alternative_win[c]) - losers++; - this_alternative_win[c] = 0; - if (this_alternative[c] == (int) NO_REGS) - bad = 1; - /* But count the pair only once in the total badness of - this alternative, if the pair can be a dummy reload. */ - value - = find_dummy_reload (recog_operand[i], recog_operand[c], - recog_operand_loc[i], recog_operand_loc[c], - this_alternative[c], -1); - - if (value != 0) - losers--; - } - /* This can be fixed with reloads if the operand - we are supposed to match can be fixed with reloads. */ - badop = 0; - this_alternative[i] = this_alternative[c]; - break; - - case 'p': - /* All necessary reloads for an address_operand - were handled in find_reloads_address. */ - this_alternative[i] = (int) ALL_REGS; - win = 1; - break; - - case 'm': - if (force_reload) - break; - if (GET_CODE (operand) == MEM - || (GET_CODE (operand) == REG - && REGNO (operand) >= FIRST_PSEUDO_REGISTER - && reg_renumber[REGNO (operand)] < 0)) - win = 1; - if (CONSTANT_P (operand)) - badop = 0; - break; - - case '<': - if (GET_CODE (operand) == MEM - && ! address_reloaded[i] - && (GET_CODE (XEXP (operand, 0)) == PRE_DEC - || GET_CODE (XEXP (operand, 0)) == POST_DEC)) - win = 1; - break; - - case '>': - if (GET_CODE (operand) == MEM - && ! address_reloaded[i] - && (GET_CODE (XEXP (operand, 0)) == PRE_INC - || GET_CODE (XEXP (operand, 0)) == POST_INC)) - win = 1; - break; - - /* Memory operand whose address is not offsettable. */ - case 'V': - if (force_reload) - break; - if (GET_CODE (operand) == MEM - && ! (ind_levels ? offsettable_memref_p (operand) - : offsettable_nonstrict_memref_p (operand)) - /* Certain mem addresses will become offsettable - after they themselves are reloaded. This is important; - we don't want our own handling of unoffsettables - to override the handling of reg_equiv_address. */ - && !(GET_CODE (XEXP (operand, 0)) == REG - && (ind_levels == 0 - || reg_equiv_address[REGNO (XEXP (operand, 0))] != 0))) - win = 1; - break; - - /* Memory operand whose address is offsettable. */ - case 'o': - if (force_reload) - break; - if ((GET_CODE (operand) == MEM - /* If IND_LEVELS, find_reloads_address won't reload a - pseudo that didn't get a hard reg, so we have to - reject that case. */ - && (ind_levels ? offsettable_memref_p (operand) - : offsettable_nonstrict_memref_p (operand))) - /* Certain mem addresses will become offsettable - after they themselves are reloaded. This is important; - we don't want our own handling of unoffsettables - to override the handling of reg_equiv_address. */ - || (GET_CODE (operand) == MEM - && GET_CODE (XEXP (operand, 0)) == REG - && (ind_levels == 0 - || reg_equiv_address[REGNO (XEXP (operand, 0))] != 0)) - || (GET_CODE (operand) == REG - && REGNO (operand) >= FIRST_PSEUDO_REGISTER - && reg_renumber[REGNO (operand)] < 0)) - win = 1; - if (CONSTANT_P (operand) || GET_CODE (operand) == MEM) - badop = 0; - offmemok = 1; - break; - - case '&': - /* Output operand that is stored before the need for the - input operands (and their index registers) is over. */ - earlyclobber = 1, this_earlyclobber = 1; - break; - - case 'E': - /* Match any floating double constant, but only if - we can examine the bits of it reliably. */ - if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT - || HOST_BITS_PER_WIDE_INT != BITS_PER_WORD) - && GET_MODE (operand) != VOIDmode && ! flag_pretend_float) - break; - if (GET_CODE (operand) == CONST_DOUBLE) - win = 1; - break; - - case 'F': - if (GET_CODE (operand) == CONST_DOUBLE) - win = 1; - break; - - case 'G': - case 'H': - if (GET_CODE (operand) == CONST_DOUBLE - && CONST_DOUBLE_OK_FOR_LETTER_P (operand, c)) - win = 1; - break; - - case 's': - if (GET_CODE (operand) == CONST_INT - || (GET_CODE (operand) == CONST_DOUBLE - && GET_MODE (operand) == VOIDmode)) - break; - case 'i': - if (CONSTANT_P (operand) -#ifdef LEGITIMATE_PIC_OPERAND_P - && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (operand)) -#endif - ) - win = 1; - break; - - case 'n': - if (GET_CODE (operand) == CONST_INT - || (GET_CODE (operand) == CONST_DOUBLE - && GET_MODE (operand) == VOIDmode)) - win = 1; - break; - - case 'I': - case 'J': - case 'K': - case 'L': - case 'M': - case 'N': - case 'O': - case 'P': - if (GET_CODE (operand) == CONST_INT - && CONST_OK_FOR_LETTER_P (INTVAL (operand), c)) - win = 1; - break; - - case 'X': - win = 1; - break; - - case 'g': - if (! force_reload - /* A PLUS is never a valid operand, but reload can make - it from a register when eliminating registers. */ - && GET_CODE (operand) != PLUS - /* A SCRATCH is not a valid operand. */ - && GET_CODE (operand) != SCRATCH -#ifdef LEGITIMATE_PIC_OPERAND_P - && (! CONSTANT_P (operand) - || ! flag_pic - || LEGITIMATE_PIC_OPERAND_P (operand)) -#endif - && (GENERAL_REGS == ALL_REGS - || GET_CODE (operand) != REG - || (REGNO (operand) >= FIRST_PSEUDO_REGISTER - && reg_renumber[REGNO (operand)] < 0))) - win = 1; - /* Drop through into 'r' case */ - - case 'r': - this_alternative[i] - = (int) reg_class_subunion[this_alternative[i]][(int) GENERAL_REGS]; - goto reg; - -#ifdef EXTRA_CONSTRAINT - case 'Q': - case 'R': - case 'S': - case 'T': - case 'U': - if (EXTRA_CONSTRAINT (operand, c)) - win = 1; - break; -#endif - - default: - this_alternative[i] - = (int) reg_class_subunion[this_alternative[i]][(int) REG_CLASS_FROM_LETTER (c)]; - - reg: - if (GET_MODE (operand) == BLKmode) - break; - winreg = 1; - if (GET_CODE (operand) == REG - && reg_fits_class_p (operand, this_alternative[i], - offset, GET_MODE (recog_operand[i]))) - win = 1; - break; - } - - constraints[i] = p; - - /* If this operand could be handled with a reg, - and some reg is allowed, then this operand can be handled. */ - if (winreg && this_alternative[i] != (int) NO_REGS) - badop = 0; - - /* Record which operands fit this alternative. */ - this_alternative_earlyclobber[i] = earlyclobber; - if (win && ! force_reload) - this_alternative_win[i] = 1; - else - { - this_alternative_offmemok[i] = offmemok; - losers++; - if (badop) - bad = 1; - /* Alternative loses if it has no regs for a reg operand. */ - if (GET_CODE (operand) == REG - && this_alternative[i] == (int) NO_REGS - && this_alternative_matches[i] < 0) - bad = 1; - - /* Alternative loses if it requires a type of reload not - permitted for this insn. We can always reload SCRATCH - and objects with a REG_UNUSED note. */ - if (GET_CODE (operand) != SCRATCH - && modified[i] != RELOAD_READ && no_output_reloads - && ! find_reg_note (insn, REG_UNUSED, operand)) - bad = 1; - else if (modified[i] != RELOAD_WRITE && no_input_reloads) - bad = 1; - - /* We prefer to reload pseudos over reloading other things, - since such reloads may be able to be eliminated later. - If we are reloading a SCRATCH, we won't be generating any - insns, just using a register, so it is also preferred. - So bump REJECT in other cases. */ - if (GET_CODE (operand) != REG && GET_CODE (operand) != SCRATCH) - reject++; - } - - /* If this operand is a pseudo register that didn't get a hard - reg and this alternative accepts some register, see if the - class that we want is a subset of the preferred class for this - register. If not, but it intersects that class, use the - preferred class instead. If it does not intersect the preferred - class, show that usage of this alternative should be discouraged; - it will be discouraged more still if the register is `preferred - or nothing'. We do this because it increases the chance of - reusing our spill register in a later insn and avoiding a pair - of memory stores and loads. - - Don't bother with this if this alternative will accept this - operand. - - Don't do this for a multiword operand, if - we have to worry about small classes, because making reg groups - harder to allocate is asking for trouble. - - Don't do this if the preferred class has only one register - because we might otherwise exhaust the class. */ - - - if (! win && this_alternative[i] != (int) NO_REGS -#ifdef SMALL_REGISTER_CLASSES - && GET_MODE_SIZE (operand_mode[i]) <= UNITS_PER_WORD -#endif - && reg_class_size[(int) preferred_class[i]] > 1) - { - if (! reg_class_subset_p (this_alternative[i], - preferred_class[i])) - { - /* Since we don't have a way of forming the intersection, - we just do something special if the preferred class - is a subset of the class we have; that's the most - common case anyway. */ - if (reg_class_subset_p (preferred_class[i], - this_alternative[i])) - this_alternative[i] = (int) preferred_class[i]; - else - reject += (1 + pref_or_nothing[i]); - } - } - } - - /* Now see if any output operands that are marked "earlyclobber" - in this alternative conflict with any input operands - or any memory addresses. */ - - for (i = 0; i < noperands; i++) - if (this_alternative_earlyclobber[i] - && this_alternative_win[i]) - { - struct decomposition early_data; - - early_data = decompose (recog_operand[i]); - - if (modified[i] == RELOAD_READ) - { - if (this_insn_is_asm) - warning_for_asm (this_insn, - "`&' constraint used with input operand"); - else - abort (); - continue; - } - - if (this_alternative[i] == NO_REGS) - { - this_alternative_earlyclobber[i] = 0; - if (this_insn_is_asm) - error_for_asm (this_insn, - "`&' constraint used with no register class"); - else - abort (); - } - - for (j = 0; j < noperands; j++) - /* Is this an input operand or a memory ref? */ - if ((GET_CODE (recog_operand[j]) == MEM - || modified[j] != RELOAD_WRITE) - && j != i - /* Ignore things like match_operator operands. */ - && *constraints1[j] != 0 - /* Don't count an input operand that is constrained to match - the early clobber operand. */ - && ! (this_alternative_matches[j] == i - && rtx_equal_p (recog_operand[i], recog_operand[j])) - /* Is it altered by storing the earlyclobber operand? */ - && !immune_p (recog_operand[j], recog_operand[i], early_data)) - { - /* If the output is in a single-reg class, - it's costly to reload it, so reload the input instead. */ - if (reg_class_size[this_alternative[i]] == 1 - && (GET_CODE (recog_operand[j]) == REG - || GET_CODE (recog_operand[j]) == SUBREG)) - { - losers++; - this_alternative_win[j] = 0; - } - else - break; - } - /* If an earlyclobber operand conflicts with something, - it must be reloaded, so request this and count the cost. */ - if (j != noperands) - { - losers++; - this_alternative_win[i] = 0; - for (j = 0; j < noperands; j++) - if (this_alternative_matches[j] == i - && this_alternative_win[j]) - { - this_alternative_win[j] = 0; - losers++; - } - } - } - - /* If one alternative accepts all the operands, no reload required, - choose that alternative; don't consider the remaining ones. */ - if (losers == 0) - { - /* Unswap these so that they are never swapped at `finish'. */ - if (commutative >= 0) - { - recog_operand[commutative] = substed_operand[commutative]; - recog_operand[commutative + 1] - = substed_operand[commutative + 1]; - } - for (i = 0; i < noperands; i++) - { - goal_alternative_win[i] = 1; - goal_alternative[i] = this_alternative[i]; - goal_alternative_offmemok[i] = this_alternative_offmemok[i]; - goal_alternative_matches[i] = this_alternative_matches[i]; - goal_alternative_earlyclobber[i] - = this_alternative_earlyclobber[i]; - } - goal_alternative_number = this_alternative_number; - goal_alternative_swapped = swapped; - goal_earlyclobber = this_earlyclobber; - goto finish; - } - - /* REJECT, set by the ! and ? constraint characters and when a register - would be reloaded into a non-preferred class, discourages the use of - this alternative for a reload goal. REJECT is incremented by three - for each ? and one for each non-preferred class. */ - losers = losers * 3 + reject; - - /* If this alternative can be made to work by reloading, - and it needs less reloading than the others checked so far, - record it as the chosen goal for reloading. */ - if (! bad && best > losers) - { - for (i = 0; i < noperands; i++) - { - goal_alternative[i] = this_alternative[i]; - goal_alternative_win[i] = this_alternative_win[i]; - goal_alternative_offmemok[i] = this_alternative_offmemok[i]; - goal_alternative_matches[i] = this_alternative_matches[i]; - goal_alternative_earlyclobber[i] - = this_alternative_earlyclobber[i]; - } - goal_alternative_swapped = swapped; - best = losers; - goal_alternative_number = this_alternative_number; - goal_earlyclobber = this_earlyclobber; - } - } - - /* If insn is commutative (it's safe to exchange a certain pair of operands) - then we need to try each alternative twice, - the second time matching those two operands - as if we had exchanged them. - To do this, really exchange them in operands. - - If we have just tried the alternatives the second time, - return operands to normal and drop through. */ - - if (commutative >= 0) - { - swapped = !swapped; - if (swapped) - { - register enum reg_class tclass; - register int t; - - recog_operand[commutative] = substed_operand[commutative + 1]; - recog_operand[commutative + 1] = substed_operand[commutative]; - - tclass = preferred_class[commutative]; - preferred_class[commutative] = preferred_class[commutative + 1]; - preferred_class[commutative + 1] = tclass; - - t = pref_or_nothing[commutative]; - pref_or_nothing[commutative] = pref_or_nothing[commutative + 1]; - pref_or_nothing[commutative + 1] = t; - - bcopy (constraints1, constraints, noperands * sizeof (char *)); - goto try_swapped; - } - else - { - recog_operand[commutative] = substed_operand[commutative]; - recog_operand[commutative + 1] = substed_operand[commutative + 1]; - } - } - - /* The operands don't meet the constraints. - goal_alternative describes the alternative - that we could reach by reloading the fewest operands. - Reload so as to fit it. */ - - if (best == MAX_RECOG_OPERANDS + 300) - { - /* No alternative works with reloads?? */ - if (insn_code_number >= 0) - abort (); - error_for_asm (insn, "inconsistent operand constraints in an `asm'"); - /* Avoid further trouble with this insn. */ - PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx); - n_reloads = 0; - return; - } - - /* Jump to `finish' from above if all operands are valid already. - In that case, goal_alternative_win is all 1. */ - finish: - - /* Right now, for any pair of operands I and J that are required to match, - with I < J, - goal_alternative_matches[J] is I. - Set up goal_alternative_matched as the inverse function: - goal_alternative_matched[I] = J. */ - - for (i = 0; i < noperands; i++) - goal_alternative_matched[i] = -1; - - for (i = 0; i < noperands; i++) - if (! goal_alternative_win[i] - && goal_alternative_matches[i] >= 0) - goal_alternative_matched[goal_alternative_matches[i]] = i; - - /* If the best alternative is with operands 1 and 2 swapped, - consider them swapped before reporting the reloads. Update the - operand numbers of any reloads already pushed. */ - - if (goal_alternative_swapped) - { - register rtx tem; - - tem = substed_operand[commutative]; - substed_operand[commutative] = substed_operand[commutative + 1]; - substed_operand[commutative + 1] = tem; - tem = recog_operand[commutative]; - recog_operand[commutative] = recog_operand[commutative + 1]; - recog_operand[commutative + 1] = tem; - - for (i = 0; i < n_reloads; i++) - { - if (reload_opnum[i] == commutative) - reload_opnum[i] = commutative + 1; - else if (reload_opnum[i] == commutative + 1) - reload_opnum[i] = commutative; - } - } - - /* Perform whatever substitutions on the operands we are supposed - to make due to commutativity or replacement of registers - with equivalent constants or memory slots. */ - - for (i = 0; i < noperands; i++) - { - *recog_operand_loc[i] = substed_operand[i]; - /* While we are looping on operands, initialize this. */ - operand_reloadnum[i] = -1; - - /* If this is an earlyclobber operand, we need to widen the scope. - The reload must remain valid from the start of the insn being - reloaded until after the operand is stored into its destination. - We approximate this with RELOAD_OTHER even though we know that we - do not conflict with RELOAD_FOR_INPUT_ADDRESS reloads. - - One special case that is worth checking is when we have an - output that is earlyclobber but isn't used past the insn (typically - a SCRATCH). In this case, we only need have the reload live - through the insn itself, but not for any of our input or output - reloads. - - In any case, anything needed to address this operand can remain - however they were previously categorized. */ - - if (goal_alternative_earlyclobber[i]) - operand_type[i] - = (find_reg_note (insn, REG_UNUSED, recog_operand[i]) - ? RELOAD_FOR_INSN : RELOAD_OTHER); - } - - /* Any constants that aren't allowed and can't be reloaded - into registers are here changed into memory references. */ - for (i = 0; i < noperands; i++) - if (! goal_alternative_win[i] - && CONSTANT_P (recog_operand[i]) - && (PREFERRED_RELOAD_CLASS (recog_operand[i], - (enum reg_class) goal_alternative[i]) - == NO_REGS) - && operand_mode[i] != VOIDmode) - { - *recog_operand_loc[i] = recog_operand[i] - = find_reloads_toplev (force_const_mem (operand_mode[i], - recog_operand[i]), - i, address_type[i], ind_levels, 0); - if (alternative_allows_memconst (constraints1[i], - goal_alternative_number)) - goal_alternative_win[i] = 1; - } - - /* Now record reloads for all the operands that need them. */ - for (i = 0; i < noperands; i++) - if (! goal_alternative_win[i]) - { - /* Operands that match previous ones have already been handled. */ - if (goal_alternative_matches[i] >= 0) - ; - /* Handle an operand with a nonoffsettable address - appearing where an offsettable address will do - by reloading the address into a base register. */ - else if (goal_alternative_matched[i] == -1 - && goal_alternative_offmemok[i] - && GET_CODE (recog_operand[i]) == MEM) - { - operand_reloadnum[i] - = push_reload (XEXP (recog_operand[i], 0), NULL_RTX, - &XEXP (recog_operand[i], 0), NULL_PTR, - BASE_REG_CLASS, GET_MODE (XEXP (recog_operand[i], 0)), - VOIDmode, 0, 0, i, RELOAD_FOR_INPUT); - reload_inc[operand_reloadnum[i]] - = GET_MODE_SIZE (GET_MODE (recog_operand[i])); - - /* If this operand is an output, we will have made any - reloads for its address as RELOAD_FOR_OUTPUT_ADDRESS, but - now we are treating part of the operand as an input, so - we must change these to RELOAD_FOR_INPUT_ADDRESS. */ - - if (operand_type[i] == RELOAD_FOR_OUTPUT) - for (j = 0; j < n_reloads; j++) - if (reload_opnum[j] == i - && reload_when_needed[j] == RELOAD_FOR_OUTPUT_ADDRESS) - reload_when_needed[j] = RELOAD_FOR_INPUT_ADDRESS; - } - else if (goal_alternative_matched[i] == -1) - operand_reloadnum[i] = - push_reload (modified[i] != RELOAD_WRITE ? recog_operand[i] : 0, - modified[i] != RELOAD_READ ? recog_operand[i] : 0, - (modified[i] != RELOAD_WRITE ? - recog_operand_loc[i] : 0), - modified[i] != RELOAD_READ ? recog_operand_loc[i] : 0, - (enum reg_class) goal_alternative[i], - (modified[i] == RELOAD_WRITE - ? VOIDmode : operand_mode[i]), - (modified[i] == RELOAD_READ - ? VOIDmode : operand_mode[i]), - (insn_code_number < 0 ? 0 - : insn_operand_strict_low[insn_code_number][i]), - 0, i, operand_type[i]); - /* In a matching pair of operands, one must be input only - and the other must be output only. - Pass the input operand as IN and the other as OUT. */ - else if (modified[i] == RELOAD_READ - && modified[goal_alternative_matched[i]] == RELOAD_WRITE) - { - operand_reloadnum[i] - = push_reload (recog_operand[i], - recog_operand[goal_alternative_matched[i]], - recog_operand_loc[i], - recog_operand_loc[goal_alternative_matched[i]], - (enum reg_class) goal_alternative[i], - operand_mode[i], - operand_mode[goal_alternative_matched[i]], - 0, 0, i, RELOAD_OTHER); - operand_reloadnum[goal_alternative_matched[i]] = output_reloadnum; - } - else if (modified[i] == RELOAD_WRITE - && modified[goal_alternative_matched[i]] == RELOAD_READ) - { - operand_reloadnum[goal_alternative_matched[i]] - = push_reload (recog_operand[goal_alternative_matched[i]], - recog_operand[i], - recog_operand_loc[goal_alternative_matched[i]], - recog_operand_loc[i], - (enum reg_class) goal_alternative[i], - operand_mode[goal_alternative_matched[i]], - operand_mode[i], - 0, 0, i, RELOAD_OTHER); - operand_reloadnum[i] = output_reloadnum; - } - else if (insn_code_number >= 0) - abort (); - else - { - error_for_asm (insn, "inconsistent operand constraints in an `asm'"); - /* Avoid further trouble with this insn. */ - PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx); - n_reloads = 0; - return; - } - } - else if (goal_alternative_matched[i] < 0 - && goal_alternative_matches[i] < 0 - && optimize) - { - /* For each non-matching operand that's a MEM or a pseudo-register - that didn't get a hard register, make an optional reload. - This may get done even if the insn needs no reloads otherwise. */ - - rtx operand = recog_operand[i]; - - while (GET_CODE (operand) == SUBREG) - operand = XEXP (operand, 0); - if ((GET_CODE (operand) == MEM - || (GET_CODE (operand) == REG - && REGNO (operand) >= FIRST_PSEUDO_REGISTER)) - && (enum reg_class) goal_alternative[i] != NO_REGS - && ! no_input_reloads - /* Optional output reloads don't do anything and we mustn't - make in-out reloads on insns that are not permitted output - reloads. */ - && (modified[i] == RELOAD_READ - || (modified[i] == RELOAD_READ_WRITE && ! no_output_reloads))) - operand_reloadnum[i] - = push_reload (modified[i] != RELOAD_WRITE ? recog_operand[i] : 0, - modified[i] != RELOAD_READ ? recog_operand[i] : 0, - (modified[i] != RELOAD_WRITE - ? recog_operand_loc[i] : 0), - (modified[i] != RELOAD_READ - ? recog_operand_loc[i] : 0), - (enum reg_class) goal_alternative[i], - (modified[i] == RELOAD_WRITE - ? VOIDmode : operand_mode[i]), - (modified[i] == RELOAD_READ - ? VOIDmode : operand_mode[i]), - (insn_code_number < 0 ? 0 - : insn_operand_strict_low[insn_code_number][i]), - 1, i, operand_type[i]); - } - else if (goal_alternative_matches[i] >= 0 - && goal_alternative_win[goal_alternative_matches[i]] - && modified[i] == RELOAD_READ - && modified[goal_alternative_matches[i]] == RELOAD_WRITE - && ! no_input_reloads && ! no_output_reloads - && optimize) - { - /* Similarly, make an optional reload for a pair of matching - objects that are in MEM or a pseudo that didn't get a hard reg. */ - - rtx operand = recog_operand[i]; - - while (GET_CODE (operand) == SUBREG) - operand = XEXP (operand, 0); - if ((GET_CODE (operand) == MEM - || (GET_CODE (operand) == REG - && REGNO (operand) >= FIRST_PSEUDO_REGISTER)) - && ((enum reg_class) goal_alternative[goal_alternative_matches[i]] - != NO_REGS)) - operand_reloadnum[i] = operand_reloadnum[goal_alternative_matches[i]] - = push_reload (recog_operand[goal_alternative_matches[i]], - recog_operand[i], - recog_operand_loc[goal_alternative_matches[i]], - recog_operand_loc[i], - (enum reg_class) goal_alternative[goal_alternative_matches[i]], - operand_mode[goal_alternative_matches[i]], - operand_mode[i], - 0, 1, goal_alternative_matches[i], RELOAD_OTHER); - } - - /* Record the values of the earlyclobber operands for the caller. */ - if (goal_earlyclobber) - for (i = 0; i < noperands; i++) - if (goal_alternative_earlyclobber[i]) - reload_earlyclobbers[n_earlyclobbers++] = recog_operand[i]; - - /* If this insn pattern contains any MATCH_DUP's, make sure that - they will be substituted if the operands they match are substituted. - Also do now any substitutions we already did on the operands. - - Don't do this if we aren't making replacements because we might be - propagating things allocated by frame pointer elimination into places - it doesn't expect. */ - - if (insn_code_number >= 0 && replace) - for (i = insn_n_dups[insn_code_number] - 1; i >= 0; i--) - { - int opno = recog_dup_num[i]; - *recog_dup_loc[i] = *recog_operand_loc[opno]; - if (operand_reloadnum[opno] >= 0) - push_replacement (recog_dup_loc[i], operand_reloadnum[opno], - insn_operand_mode[insn_code_number][opno]); - } - -#if 0 - /* This loses because reloading of prior insns can invalidate the equivalence - (or at least find_equiv_reg isn't smart enough to find it any more), - causing this insn to need more reload regs than it needed before. - It may be too late to make the reload regs available. - Now this optimization is done safely in choose_reload_regs. */ - - /* For each reload of a reg into some other class of reg, - search for an existing equivalent reg (same value now) in the right class. - We can use it as long as we don't need to change its contents. */ - for (i = 0; i < n_reloads; i++) - if (reload_reg_rtx[i] == 0 - && reload_in[i] != 0 - && GET_CODE (reload_in[i]) == REG - && reload_out[i] == 0) - { - reload_reg_rtx[i] - = find_equiv_reg (reload_in[i], insn, reload_reg_class[i], -1, - static_reload_reg_p, 0, reload_inmode[i]); - /* Prevent generation of insn to load the value - because the one we found already has the value. */ - if (reload_reg_rtx[i]) - reload_in[i] = reload_reg_rtx[i]; - } -#endif - - /* Perhaps an output reload can be combined with another - to reduce needs by one. */ - if (!goal_earlyclobber) - combine_reloads (); - - /* If we have a pair of reloads for parts of an address, they are reloading - the same object, the operands themselves were not reloaded, and they - are for two operands that are supposed to match, merge the reloads and - change the type of the surviving reload to RELOAD_FOR_OPERAND_ADDRESS. */ - - for (i = 0; i < n_reloads; i++) - { - int k; - - for (j = i + 1; j < n_reloads; j++) - if ((reload_when_needed[i] == RELOAD_FOR_INPUT_ADDRESS - || reload_when_needed[i] == RELOAD_FOR_OUTPUT_ADDRESS) - && (reload_when_needed[j] == RELOAD_FOR_INPUT_ADDRESS - || reload_when_needed[j] == RELOAD_FOR_OUTPUT_ADDRESS) - && rtx_equal_p (reload_in[i], reload_in[j]) - && (operand_reloadnum[reload_opnum[i]] < 0 - || reload_optional[operand_reloadnum[reload_opnum[i]]]) - && (operand_reloadnum[reload_opnum[j]] < 0 - || reload_optional[operand_reloadnum[reload_opnum[j]]]) - && (goal_alternative_matches[reload_opnum[i]] == reload_opnum[j] - || (goal_alternative_matches[reload_opnum[j]] - == reload_opnum[i]))) - { - for (k = 0; k < n_replacements; k++) - if (replacements[k].what == j) - replacements[k].what = i; - - reload_when_needed[i] = RELOAD_FOR_OPERAND_ADDRESS; - reload_in[j] = 0; - } - } - - /* Scan all the reloads and update their type. - If a reload is for the address of an operand and we didn't reload - that operand, change the type. Similarly, change the operand number - of a reload when two operands match. If a reload is optional, treat it - as though the operand isn't reloaded. - - ??? This latter case is somewhat odd because if we do the optional - reload, it means the object is hanging around. Thus we need only - do the address reload if the optional reload was NOT done. - - Change secondary reloads to be the address type of their operand, not - the normal type. - - If an operand's reload is now RELOAD_OTHER, change any - RELOAD_FOR_INPUT_ADDRESS reloads of that operand to - RELOAD_FOR_OTHER_ADDRESS. */ - - for (i = 0; i < n_reloads; i++) - { - if (reload_secondary_p[i] - && reload_when_needed[i] == operand_type[reload_opnum[i]]) - reload_when_needed[i] = address_type[reload_opnum[i]]; - - if ((reload_when_needed[i] == RELOAD_FOR_INPUT_ADDRESS - || reload_when_needed[i] == RELOAD_FOR_OUTPUT_ADDRESS) - && (operand_reloadnum[reload_opnum[i]] < 0 - || reload_optional[operand_reloadnum[reload_opnum[i]]])) - reload_when_needed[i] = RELOAD_FOR_OPERAND_ADDRESS; - - if (reload_when_needed[i] == RELOAD_FOR_INPUT_ADDRESS - && operand_reloadnum[reload_opnum[i]] >= 0 - && (reload_when_needed[operand_reloadnum[reload_opnum[i]]] - == RELOAD_OTHER)) - reload_when_needed[i] = RELOAD_FOR_OTHER_ADDRESS; - - if (goal_alternative_matches[reload_opnum[i]] >= 0) - reload_opnum[i] = goal_alternative_matches[reload_opnum[i]]; - } - - /* See if we have any reloads that are now allowed to be merged - because we've changed when the reload is needed to - RELOAD_FOR_OPERAND_ADDRESS or RELOAD_FOR_OTHER_ADDRESS. Only - check for the most common cases. */ - - for (i = 0; i < n_reloads; i++) - if (reload_in[i] != 0 && reload_out[i] == 0 - && (reload_when_needed[i] == RELOAD_FOR_OPERAND_ADDRESS - || reload_when_needed[i] == RELOAD_FOR_OTHER_ADDRESS)) - for (j = 0; j < n_reloads; j++) - if (i != j && reload_in[j] != 0 && reload_out[j] == 0 - && reload_when_needed[j] == reload_when_needed[i] - && MATCHES (reload_in[i], reload_in[j])) - { - reload_opnum[i] = MIN (reload_opnum[i], reload_opnum[j]); - transfer_replacements (i, j); - reload_in[j] = 0; - } - -#else /* no REGISTER_CONSTRAINTS */ - int noperands; - int insn_code_number; - int goal_earlyclobber = 0; /* Always 0, to make combine_reloads happen. */ - register int i; - rtx body = PATTERN (insn); - - n_reloads = 0; - n_replacements = 0; - n_earlyclobbers = 0; - replace_reloads = replace; - this_insn = insn; - - /* Find what kind of insn this is. NOPERANDS gets number of operands. - Store the operand values in RECOG_OPERAND and the locations - of the words in the insn that point to them in RECOG_OPERAND_LOC. - Return if the insn needs no reload processing. */ - - switch (GET_CODE (body)) - { - case USE: - case CLOBBER: - case ASM_INPUT: - case ADDR_VEC: - case ADDR_DIFF_VEC: - return; - - case PARALLEL: - case SET: - noperands = asm_noperands (body); - if (noperands >= 0) - { - /* This insn is an `asm' with operands. - First, find out how many operands, and allocate space. */ - - insn_code_number = -1; - /* ??? This is a bug! ??? - Give up and delete this insn if it has too many operands. */ - if (noperands > MAX_RECOG_OPERANDS) - abort (); - - /* Now get the operand values out of the insn. */ - - decode_asm_operands (body, recog_operand, recog_operand_loc, - NULL_PTR, NULL_PTR); - break; - } - - default: - /* Ordinary insn: recognize it, allocate space for operands and - constraints, and get them out via insn_extract. */ - - insn_code_number = recog_memoized (insn); - noperands = insn_n_operands[insn_code_number]; - insn_extract (insn); - } - - if (noperands == 0) - return; - - for (i = 0; i < noperands; i++) - { - register RTX_CODE code = GET_CODE (recog_operand[i]); - int is_set_dest = GET_CODE (body) == SET && (i == 0); - - if (insn_code_number >= 0) - if (insn_operand_address_p[insn_code_number][i]) - find_reloads_address (VOIDmode, NULL_PTR, - recog_operand[i], recog_operand_loc[i], - i, RELOAD_FOR_INPUT, ind_levels); - - /* In these cases, we can't tell if the operand is an input - or an output, so be conservative. In practice it won't be - problem. */ - - if (code == MEM) - find_reloads_address (GET_MODE (recog_operand[i]), - recog_operand_loc[i], - XEXP (recog_operand[i], 0), - &XEXP (recog_operand[i], 0), - i, RELOAD_OTHER, ind_levels); - if (code == SUBREG) - recog_operand[i] = *recog_operand_loc[i] - = find_reloads_toplev (recog_operand[i], i, RELOAD_OTHER, - ind_levels, is_set_dest); - if (code == REG) - { - register int regno = REGNO (recog_operand[i]); - if (reg_equiv_constant[regno] != 0 && !is_set_dest) - recog_operand[i] = *recog_operand_loc[i] - = reg_equiv_constant[regno]; -#if 0 /* This might screw code in reload1.c to delete prior output-reload - that feeds this insn. */ - if (reg_equiv_mem[regno] != 0) - recog_operand[i] = *recog_operand_loc[i] - = reg_equiv_mem[regno]; -#endif - } - } - - /* Perhaps an output reload can be combined with another - to reduce needs by one. */ - if (!goal_earlyclobber) - combine_reloads (); -#endif /* no REGISTER_CONSTRAINTS */ -} - -/* Return 1 if alternative number ALTNUM in constraint-string CONSTRAINT - accepts a memory operand with constant address. */ - -static int -alternative_allows_memconst (constraint, altnum) - char *constraint; - int altnum; -{ - register int c; - /* Skip alternatives before the one requested. */ - while (altnum > 0) - { - while (*constraint++ != ','); - altnum--; - } - /* Scan the requested alternative for 'm' or 'o'. - If one of them is present, this alternative accepts memory constants. */ - while ((c = *constraint++) && c != ',' && c != '#') - if (c == 'm' || c == 'o') - return 1; - return 0; -} - -/* Scan X for memory references and scan the addresses for reloading. - Also checks for references to "constant" regs that we want to eliminate - and replaces them with the values they stand for. - We may alter X destructively if it contains a reference to such. - If X is just a constant reg, we return the equivalent value - instead of X. - - IND_LEVELS says how many levels of indirect addressing this machine - supports. - - OPNUM and TYPE identify the purpose of the reload. - - IS_SET_DEST is true if X is the destination of a SET, which is not - appropriate to be replaced by a constant. */ - -static rtx -find_reloads_toplev (x, opnum, type, ind_levels, is_set_dest) - rtx x; - int opnum; - enum reload_type type; - int ind_levels; - int is_set_dest; -{ - register RTX_CODE code = GET_CODE (x); - - register char *fmt = GET_RTX_FORMAT (code); - register int i; - - if (code == REG) - { - /* This code is duplicated for speed in find_reloads. */ - register int regno = REGNO (x); - if (reg_equiv_constant[regno] != 0 && !is_set_dest) - x = reg_equiv_constant[regno]; -#if 0 -/* This creates (subreg (mem...)) which would cause an unnecessary - reload of the mem. */ - else if (reg_equiv_mem[regno] != 0) - x = reg_equiv_mem[regno]; -#endif - else if (reg_equiv_address[regno] != 0) - { - /* If reg_equiv_address varies, it may be shared, so copy it. */ - rtx addr = reg_equiv_address[regno]; - - if (rtx_varies_p (addr)) - addr = copy_rtx (addr); - - x = gen_rtx (MEM, GET_MODE (x), addr); - RTX_UNCHANGING_P (x) = RTX_UNCHANGING_P (regno_reg_rtx[regno]); - find_reloads_address (GET_MODE (x), NULL_PTR, - XEXP (x, 0), - &XEXP (x, 0), opnum, type, ind_levels); - } - return x; - } - if (code == MEM) - { - rtx tem = x; - find_reloads_address (GET_MODE (x), &tem, XEXP (x, 0), &XEXP (x, 0), - opnum, type, ind_levels); - return tem; - } - - if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG) - { - /* Check for SUBREG containing a REG that's equivalent to a constant. - If the constant has a known value, truncate it right now. - Similarly if we are extracting a single-word of a multi-word - constant. If the constant is symbolic, allow it to be substituted - normally. push_reload will strip the subreg later. If the - constant is VOIDmode, abort because we will lose the mode of - the register (this should never happen because one of the cases - above should handle it). */ - - register int regno = REGNO (SUBREG_REG (x)); - rtx tem; - - if (subreg_lowpart_p (x) - && regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 - && reg_equiv_constant[regno] != 0 - && (tem = gen_lowpart_common (GET_MODE (x), - reg_equiv_constant[regno])) != 0) - return tem; - - if (GET_MODE_BITSIZE (GET_MODE (x)) == BITS_PER_WORD - && regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 - && reg_equiv_constant[regno] != 0 - && (tem = operand_subword (reg_equiv_constant[regno], - SUBREG_WORD (x), 0, - GET_MODE (SUBREG_REG (x)))) != 0) - return tem; - - if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 - && reg_equiv_constant[regno] != 0 - && GET_MODE (reg_equiv_constant[regno]) == VOIDmode) - abort (); - - /* If the subreg contains a reg that will be converted to a mem, - convert the subreg to a narrower memref now. - Otherwise, we would get (subreg (mem ...) ...), - which would force reload of the mem. - - We also need to do this if there is an equivalent MEM that is - not offsettable. In that case, alter_subreg would produce an - invalid address on big-endian machines. - - For machines that extend byte loads, we must not reload using - a wider mode if we have a paradoxical SUBREG. find_reloads will - force a reload in that case. So we should not do anything here. */ - - else if (regno >= FIRST_PSEUDO_REGISTER -#if defined(BYTE_LOADS_ZERO_EXTEND) || defined(BYTE_LOADS_SIGN_EXTEND) - && (GET_MODE_SIZE (GET_MODE (x)) - <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))) -#endif - && (reg_equiv_address[regno] != 0 - || (reg_equiv_mem[regno] != 0 - && (! strict_memory_address_p (GET_MODE (x), - XEXP (reg_equiv_mem[regno], 0)) - || ! offsettable_memref_p (reg_equiv_mem[regno]))))) - { - int offset = SUBREG_WORD (x) * UNITS_PER_WORD; - rtx addr = (reg_equiv_address[regno] ? reg_equiv_address[regno] - : XEXP (reg_equiv_mem[regno], 0)); -#if BYTES_BIG_ENDIAN - int size; - size = GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))); - offset += MIN (size, UNITS_PER_WORD); - size = GET_MODE_SIZE (GET_MODE (x)); - offset -= MIN (size, UNITS_PER_WORD); -#endif - addr = plus_constant (addr, offset); - x = gen_rtx (MEM, GET_MODE (x), addr); - RTX_UNCHANGING_P (x) = RTX_UNCHANGING_P (regno_reg_rtx[regno]); - find_reloads_address (GET_MODE (x), NULL_PTR, - XEXP (x, 0), - &XEXP (x, 0), opnum, type, ind_levels); - } - - } - - for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - { - if (fmt[i] == 'e') - XEXP (x, i) = find_reloads_toplev (XEXP (x, i), opnum, type, - ind_levels, is_set_dest); - } - return x; -} - -/* Return a mem ref for the memory equivalent of reg REGNO. - This mem ref is not shared with anything. */ - -static rtx -make_memloc (ad, regno) - rtx ad; - int regno; -{ - register int i; - rtx tem = reg_equiv_address[regno]; - -#if 0 /* We cannot safely reuse a memloc made here; - if the pseudo appears twice, and its mem needs a reload, - it gets two separate reloads assigned, but it only - gets substituted with the second of them; - then it can get used before that reload reg gets loaded up. */ - for (i = 0; i < n_memlocs; i++) - if (rtx_equal_p (tem, XEXP (memlocs[i], 0))) - return memlocs[i]; -#endif - - /* If TEM might contain a pseudo, we must copy it to avoid - modifying it when we do the substitution for the reload. */ - if (rtx_varies_p (tem)) - tem = copy_rtx (tem); - - tem = gen_rtx (MEM, GET_MODE (ad), tem); - RTX_UNCHANGING_P (tem) = RTX_UNCHANGING_P (regno_reg_rtx[regno]); - memlocs[n_memlocs++] = tem; - return tem; -} - -/* Record all reloads needed for handling memory address AD - which appears in *LOC in a memory reference to mode MODE - which itself is found in location *MEMREFLOC. - Note that we take shortcuts assuming that no multi-reg machine mode - occurs as part of an address. - - OPNUM and TYPE specify the purpose of this reload. - - IND_LEVELS says how many levels of indirect addressing this machine - supports. - - Value is nonzero if this address is reloaded or replaced as a whole. - This is interesting to the caller if the address is an autoincrement. - - Note that there is no verification that the address will be valid after - this routine does its work. Instead, we rely on the fact that the address - was valid when reload started. So we need only undo things that reload - could have broken. These are wrong register types, pseudos not allocated - to a hard register, and frame pointer elimination. */ - -static int -find_reloads_address (mode, memrefloc, ad, loc, opnum, type, ind_levels) - enum machine_mode mode; - rtx *memrefloc; - rtx ad; - rtx *loc; - int opnum; - enum reload_type type; - int ind_levels; -{ - register int regno; - rtx tem; - - /* If the address is a register, see if it is a legitimate address and - reload if not. We first handle the cases where we need not reload - or where we must reload in a non-standard way. */ - - if (GET_CODE (ad) == REG) - { - regno = REGNO (ad); - - if (reg_equiv_constant[regno] != 0 - && strict_memory_address_p (mode, reg_equiv_constant[regno])) - { - *loc = ad = reg_equiv_constant[regno]; - return 1; - } - - else if (reg_equiv_address[regno] != 0) - { - tem = make_memloc (ad, regno); - find_reloads_address (GET_MODE (tem), NULL_PTR, XEXP (tem, 0), - &XEXP (tem, 0), opnum, type, ind_levels); - push_reload (tem, NULL_RTX, loc, NULL_PTR, BASE_REG_CLASS, - GET_MODE (ad), VOIDmode, 0, 0, - opnum, type); - return 1; - } - - /* We can avoid a reload if the register's equivalent memory expression - is valid as an indirect memory address. */ - - else if (reg_equiv_mem[regno] != 0 && ind_levels > 0 - && strict_memory_address_p (mode, reg_equiv_mem[regno])) - return 0; - - /* The only remaining case where we can avoid a reload is if this is a - hard register that is valid as a base register and which is not the - subject of a CLOBBER in this insn. */ - - else if (regno < FIRST_PSEUDO_REGISTER && REGNO_OK_FOR_BASE_P (regno) - && ! regno_clobbered_p (regno, this_insn)) - return 0; - - /* If we do not have one of the cases above, we must do the reload. */ - push_reload (ad, NULL_RTX, loc, NULL_PTR, BASE_REG_CLASS, - GET_MODE (ad), VOIDmode, 0, 0, opnum, type); - return 1; - } - - if (strict_memory_address_p (mode, ad)) - { - /* The address appears valid, so reloads are not needed. - But the address may contain an eliminable register. - This can happen because a machine with indirect addressing - may consider a pseudo register by itself a valid address even when - it has failed to get a hard reg. - So do a tree-walk to find and eliminate all such regs. */ - - /* But first quickly dispose of a common case. */ - if (GET_CODE (ad) == PLUS - && GET_CODE (XEXP (ad, 1)) == CONST_INT - && GET_CODE (XEXP (ad, 0)) == REG - && reg_equiv_constant[REGNO (XEXP (ad, 0))] == 0) - return 0; - - subst_reg_equivs_changed = 0; - *loc = subst_reg_equivs (ad); - - if (! subst_reg_equivs_changed) - return 0; - - /* Check result for validity after substitution. */ - if (strict_memory_address_p (mode, ad)) - return 0; - } - - /* The address is not valid. We have to figure out why. One possibility - is that it is itself a MEM. This can happen when the frame pointer is - being eliminated, a pseudo is not allocated to a hard register, and the - offset between the frame and stack pointers is not its initial value. - In that case the pseudo will have been replaced by a MEM referring to - the stack pointer. */ - if (GET_CODE (ad) == MEM) - { - /* First ensure that the address in this MEM is valid. Then, unless - indirect addresses are valid, reload the MEM into a register. */ - tem = ad; - find_reloads_address (GET_MODE (ad), &tem, XEXP (ad, 0), &XEXP (ad, 0), - opnum, type, ind_levels == 0 ? 0 : ind_levels - 1); - - /* If tem was changed, then we must create a new memory reference to - hold it and store it back into memrefloc. */ - if (tem != ad && memrefloc) - { - *memrefloc = copy_rtx (*memrefloc); - copy_replacements (tem, XEXP (*memrefloc, 0)); - loc = &XEXP (*memrefloc, 0); - } - - /* Check similar cases as for indirect addresses as above except - that we can allow pseudos and a MEM since they should have been - taken care of above. */ - - if (ind_levels == 0 - || (GET_CODE (XEXP (tem, 0)) == SYMBOL_REF && ! indirect_symref_ok) - || GET_CODE (XEXP (tem, 0)) == MEM - || ! (GET_CODE (XEXP (tem, 0)) == REG - || (GET_CODE (XEXP (tem, 0)) == PLUS - && GET_CODE (XEXP (XEXP (tem, 0), 0)) == REG - && GET_CODE (XEXP (XEXP (tem, 0), 1)) == CONST_INT))) - { - /* Must use TEM here, not AD, since it is the one that will - have any subexpressions reloaded, if needed. */ - push_reload (tem, NULL_RTX, loc, NULL_PTR, - BASE_REG_CLASS, GET_MODE (tem), VOIDmode, 0, - 0, opnum, type); - return 1; - } - else - return 0; - } - - /* If we have address of a stack slot but it's not valid - (displacement is too large), compute the sum in a register. */ - else if (GET_CODE (ad) == PLUS - && (XEXP (ad, 0) == frame_pointer_rtx -#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM - || XEXP (ad, 0) == arg_pointer_rtx -#endif - || XEXP (ad, 0) == stack_pointer_rtx) - && GET_CODE (XEXP (ad, 1)) == CONST_INT) - { - /* Unshare the MEM rtx so we can safely alter it. */ - if (memrefloc) - { - rtx oldref = *memrefloc; - *memrefloc = copy_rtx (*memrefloc); - loc = &XEXP (*memrefloc, 0); - } - if (double_reg_address_ok) - { - /* Unshare the sum as well. */ - *loc = ad = copy_rtx (ad); - /* Reload the displacement into an index reg. - We assume the frame pointer or arg pointer is a base reg. */ - find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1), - INDEX_REG_CLASS, GET_MODE (ad), opnum, - type, ind_levels); - } - else - { - /* If the sum of two regs is not necessarily valid, - reload the sum into a base reg. - That will at least work. */ - find_reloads_address_part (ad, loc, BASE_REG_CLASS, Pmode, - opnum, type, ind_levels); - } - return 1; - } - - /* If we have an indexed stack slot, there are three possible reasons why - it might be invalid: The index might need to be reloaded, the address - might have been made by frame pointer elimination and hence have a - constant out of range, or both reasons might apply. - - We can easily check for an index needing reload, but even if that is the - case, we might also have an invalid constant. To avoid making the - conservative assumption and requiring two reloads, we see if this address - is valid when not interpreted strictly. If it is, the only problem is - that the index needs a reload and find_reloads_address_1 will take care - of it. - - There is still a case when we might generate an extra reload, - however. In certain cases eliminate_regs will return a MEM for a REG - (see the code there for details). In those cases, memory_address_p - applied to our address will return 0 so we will think that our offset - must be too large. But it might indeed be valid and the only problem - is that a MEM is present where a REG should be. This case should be - very rare and there doesn't seem to be any way to avoid it. - - If we decide to do something here, it must be that - `double_reg_address_ok' is true and that this address rtl was made by - eliminate_regs. We generate a reload of the fp/sp/ap + constant and - rework the sum so that the reload register will be added to the index. - This is safe because we know the address isn't shared. - - We check for fp/ap/sp as both the first and second operand of the - innermost PLUS. */ - - else if (GET_CODE (ad) == PLUS && GET_CODE (XEXP (ad, 1)) == CONST_INT - && GET_CODE (XEXP (ad, 0)) == PLUS - && (XEXP (XEXP (ad, 0), 0) == frame_pointer_rtx -#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM - || XEXP (XEXP (ad, 0), 0) == arg_pointer_rtx -#endif - || XEXP (XEXP (ad, 0), 0) == stack_pointer_rtx) - && ! memory_address_p (mode, ad)) - { - *loc = ad = gen_rtx (PLUS, GET_MODE (ad), - plus_constant (XEXP (XEXP (ad, 0), 0), - INTVAL (XEXP (ad, 1))), - XEXP (XEXP (ad, 0), 1)); - find_reloads_address_part (XEXP (ad, 0), &XEXP (ad, 0), BASE_REG_CLASS, - GET_MODE (ad), opnum, type, ind_levels); - find_reloads_address_1 (XEXP (ad, 1), 1, &XEXP (ad, 1), opnum, type, 0); - - return 1; - } - - else if (GET_CODE (ad) == PLUS && GET_CODE (XEXP (ad, 1)) == CONST_INT - && GET_CODE (XEXP (ad, 0)) == PLUS - && (XEXP (XEXP (ad, 0), 1) == frame_pointer_rtx -#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM - || XEXP (XEXP (ad, 0), 1) == arg_pointer_rtx -#endif - || XEXP (XEXP (ad, 0), 1) == stack_pointer_rtx) - && ! memory_address_p (mode, ad)) - { - *loc = ad = gen_rtx (PLUS, GET_MODE (ad), - plus_constant (XEXP (XEXP (ad, 0), 1), - INTVAL (XEXP (ad, 1))), - XEXP (XEXP (ad, 0), 0)); - find_reloads_address_part (XEXP (ad, 0), &XEXP (ad, 0), BASE_REG_CLASS, - GET_MODE (ad), opnum, type, ind_levels); - find_reloads_address_1 (XEXP (ad, 1), 1, &XEXP (ad, 1), opnum, type, 0); - - return 1; - } - - /* See if address becomes valid when an eliminable register - in a sum is replaced. */ - - tem = ad; - if (GET_CODE (ad) == PLUS) - tem = subst_indexed_address (ad); - if (tem != ad && strict_memory_address_p (mode, tem)) - { - /* Ok, we win that way. Replace any additional eliminable - registers. */ - - subst_reg_equivs_changed = 0; - tem = subst_reg_equivs (tem); - - /* Make sure that didn't make the address invalid again. */ - - if (! subst_reg_equivs_changed || strict_memory_address_p (mode, tem)) - { - *loc = tem; - return 0; - } - } - - /* If constants aren't valid addresses, reload the constant address - into a register. */ - if (CONSTANT_P (ad) && ! strict_memory_address_p (mode, ad)) - { - /* If AD is in address in the constant pool, the MEM rtx may be shared. - Unshare it so we can safely alter it. */ - if (memrefloc && GET_CODE (ad) == SYMBOL_REF - && CONSTANT_POOL_ADDRESS_P (ad)) - { - rtx oldref = *memrefloc; - *memrefloc = copy_rtx (*memrefloc); - loc = &XEXP (*memrefloc, 0); - } - - find_reloads_address_part (ad, loc, BASE_REG_CLASS, Pmode, opnum, type, - ind_levels); - return 1; - } - - return find_reloads_address_1 (ad, 0, loc, opnum, type, ind_levels); -} - -/* Find all pseudo regs appearing in AD - that are eliminable in favor of equivalent values - and do not have hard regs; replace them by their equivalents. */ - -static rtx -subst_reg_equivs (ad) - rtx ad; -{ - register RTX_CODE code = GET_CODE (ad); - register int i; - register char *fmt; - - switch (code) - { - case HIGH: - case CONST_INT: - case CONST: - case CONST_DOUBLE: - case SYMBOL_REF: - case LABEL_REF: - case PC: - case CC0: - return ad; - - case REG: - { - register int regno = REGNO (ad); - - if (reg_equiv_constant[regno] != 0) - { - subst_reg_equivs_changed = 1; - return reg_equiv_constant[regno]; - } - } - return ad; - - case PLUS: - /* Quickly dispose of a common case. */ - if (XEXP (ad, 0) == frame_pointer_rtx - && GET_CODE (XEXP (ad, 1)) == CONST_INT) - return ad; - } - - fmt = GET_RTX_FORMAT (code); - for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - if (fmt[i] == 'e') - XEXP (ad, i) = subst_reg_equivs (XEXP (ad, i)); - return ad; -} - -/* Compute the sum of X and Y, making canonicalizations assumed in an - address, namely: sum constant integers, surround the sum of two - constants with a CONST, put the constant as the second operand, and - group the constant on the outermost sum. - - This routine assumes both inputs are already in canonical form. */ - -rtx -form_sum (x, y) - rtx x, y; -{ - rtx tem; - enum machine_mode mode = GET_MODE (x); - - if (mode == VOIDmode) - mode = GET_MODE (y); - - if (mode == VOIDmode) - mode = Pmode; - - if (GET_CODE (x) == CONST_INT) - return plus_constant (y, INTVAL (x)); - else if (GET_CODE (y) == CONST_INT) - return plus_constant (x, INTVAL (y)); - else if (CONSTANT_P (x)) - tem = x, x = y, y = tem; - - if (GET_CODE (x) == PLUS && CONSTANT_P (XEXP (x, 1))) - return form_sum (XEXP (x, 0), form_sum (XEXP (x, 1), y)); - - /* Note that if the operands of Y are specified in the opposite - order in the recursive calls below, infinite recursion will occur. */ - if (GET_CODE (y) == PLUS && CONSTANT_P (XEXP (y, 1))) - return form_sum (form_sum (x, XEXP (y, 0)), XEXP (y, 1)); - - /* If both constant, encapsulate sum. Otherwise, just form sum. A - constant will have been placed second. */ - if (CONSTANT_P (x) && CONSTANT_P (y)) - { - if (GET_CODE (x) == CONST) - x = XEXP (x, 0); - if (GET_CODE (y) == CONST) - y = XEXP (y, 0); - - return gen_rtx (CONST, VOIDmode, gen_rtx (PLUS, mode, x, y)); - } - - return gen_rtx (PLUS, mode, x, y); -} - -/* If ADDR is a sum containing a pseudo register that should be - replaced with a constant (from reg_equiv_constant), - return the result of doing so, and also apply the associative - law so that the result is more likely to be a valid address. - (But it is not guaranteed to be one.) - - Note that at most one register is replaced, even if more are - replaceable. Also, we try to put the result into a canonical form - so it is more likely to be a valid address. - - In all other cases, return ADDR. */ - -static rtx -subst_indexed_address (addr) - rtx addr; -{ - rtx op0 = 0, op1 = 0, op2 = 0; - rtx tem; - int regno; - - if (GET_CODE (addr) == PLUS) - { - /* Try to find a register to replace. */ - op0 = XEXP (addr, 0), op1 = XEXP (addr, 1), op2 = 0; - if (GET_CODE (op0) == REG - && (regno = REGNO (op0)) >= FIRST_PSEUDO_REGISTER - && reg_renumber[regno] < 0 - && reg_equiv_constant[regno] != 0) - op0 = reg_equiv_constant[regno]; - else if (GET_CODE (op1) == REG - && (regno = REGNO (op1)) >= FIRST_PSEUDO_REGISTER - && reg_renumber[regno] < 0 - && reg_equiv_constant[regno] != 0) - op1 = reg_equiv_constant[regno]; - else if (GET_CODE (op0) == PLUS - && (tem = subst_indexed_address (op0)) != op0) - op0 = tem; - else if (GET_CODE (op1) == PLUS - && (tem = subst_indexed_address (op1)) != op1) - op1 = tem; - else - return addr; - - /* Pick out up to three things to add. */ - if (GET_CODE (op1) == PLUS) - op2 = XEXP (op1, 1), op1 = XEXP (op1, 0); - else if (GET_CODE (op0) == PLUS) - op2 = op1, op1 = XEXP (op0, 1), op0 = XEXP (op0, 0); - - /* Compute the sum. */ - if (op2 != 0) - op1 = form_sum (op1, op2); - if (op1 != 0) - op0 = form_sum (op0, op1); - - return op0; - } - return addr; -} - -/* Record the pseudo registers we must reload into hard registers - in a subexpression of a would-be memory address, X. - (This function is not called if the address we find is strictly valid.) - CONTEXT = 1 means we are considering regs as index regs, - = 0 means we are considering them as base regs. - - OPNUM and TYPE specify the purpose of any reloads made. - - IND_LEVELS says how many levels of indirect addressing are - supported at this point in the address. - - We return nonzero if X, as a whole, is reloaded or replaced. */ - -/* Note that we take shortcuts assuming that no multi-reg machine mode - occurs as part of an address. - Also, this is not fully machine-customizable; it works for machines - such as vaxes and 68000's and 32000's, but other possible machines - could have addressing modes that this does not handle right. */ - -static int -find_reloads_address_1 (x, context, loc, opnum, type, ind_levels) - rtx x; - int context; - rtx *loc; - int opnum; - enum reload_type type; - int ind_levels; -{ - register RTX_CODE code = GET_CODE (x); - - if (code == PLUS) - { - register rtx op0 = XEXP (x, 0); - register rtx op1 = XEXP (x, 1); - register RTX_CODE code0 = GET_CODE (op0); - register RTX_CODE code1 = GET_CODE (op1); - if (code0 == MULT || code0 == SIGN_EXTEND || code1 == MEM) - { - find_reloads_address_1 (op0, 1, &XEXP (x, 0), opnum, type, - ind_levels); - find_reloads_address_1 (op1, 0, &XEXP (x, 1), opnum, type, - ind_levels); - } - else if (code1 == MULT || code1 == SIGN_EXTEND || code0 == MEM) - { - find_reloads_address_1 (op0, 0, &XEXP (x, 0), opnum, type, - ind_levels); - find_reloads_address_1 (op1, 1, &XEXP (x, 1), opnum, type, - ind_levels); - } - else if (code0 == CONST_INT || code0 == CONST - || code0 == SYMBOL_REF || code0 == LABEL_REF) - find_reloads_address_1 (op1, 0, &XEXP (x, 1), opnum, type, ind_levels); - else if (code1 == CONST_INT || code1 == CONST - || code1 == SYMBOL_REF || code1 == LABEL_REF) - find_reloads_address_1 (op0, 0, &XEXP (x, 0), opnum, type, ind_levels); - else if (code0 == REG && code1 == REG) - { - if (REG_OK_FOR_INDEX_P (op0) - && REG_OK_FOR_BASE_P (op1)) - return 0; - else if (REG_OK_FOR_INDEX_P (op1) - && REG_OK_FOR_BASE_P (op0)) - return 0; - else if (REG_OK_FOR_BASE_P (op1)) - find_reloads_address_1 (op0, 1, &XEXP (x, 0), opnum, type, - ind_levels); - else if (REG_OK_FOR_BASE_P (op0)) - find_reloads_address_1 (op1, 1, &XEXP (x, 1), opnum, type, - ind_levels); - else if (REG_OK_FOR_INDEX_P (op1)) - find_reloads_address_1 (op0, 0, &XEXP (x, 0), opnum, type, - ind_levels); - else if (REG_OK_FOR_INDEX_P (op0)) - find_reloads_address_1 (op1, 0, &XEXP (x, 1), opnum, type, - ind_levels); - else - { - find_reloads_address_1 (op0, 1, &XEXP (x, 0), opnum, type, - ind_levels); - find_reloads_address_1 (op1, 0, &XEXP (x, 1), opnum, type, - ind_levels); - } - } - else if (code0 == REG) - { - find_reloads_address_1 (op0, 1, &XEXP (x, 0), opnum, type, - ind_levels); - find_reloads_address_1 (op1, 0, &XEXP (x, 1), opnum, type, - ind_levels); - } - else if (code1 == REG) - { - find_reloads_address_1 (op1, 1, &XEXP (x, 1), opnum, type, - ind_levels); - find_reloads_address_1 (op0, 0, &XEXP (x, 0), opnum, type, - ind_levels); - } - } - else if (code == POST_INC || code == POST_DEC - || code == PRE_INC || code == PRE_DEC) - { - if (GET_CODE (XEXP (x, 0)) == REG) - { - register int regno = REGNO (XEXP (x, 0)); - int value = 0; - rtx x_orig = x; - - /* A register that is incremented cannot be constant! */ - if (regno >= FIRST_PSEUDO_REGISTER - && reg_equiv_constant[regno] != 0) - abort (); - - /* Handle a register that is equivalent to a memory location - which cannot be addressed directly. */ - if (reg_equiv_address[regno] != 0) - { - rtx tem = make_memloc (XEXP (x, 0), regno); - /* First reload the memory location's address. */ - find_reloads_address (GET_MODE (tem), 0, XEXP (tem, 0), - &XEXP (tem, 0), opnum, type, ind_levels); - /* Put this inside a new increment-expression. */ - x = gen_rtx (GET_CODE (x), GET_MODE (x), tem); - /* Proceed to reload that, as if it contained a register. */ - } - - /* If we have a hard register that is ok as an index, - don't make a reload. If an autoincrement of a nice register - isn't "valid", it must be that no autoincrement is "valid". - If that is true and something made an autoincrement anyway, - this must be a special context where one is allowed. - (For example, a "push" instruction.) - We can't improve this address, so leave it alone. */ - - /* Otherwise, reload the autoincrement into a suitable hard reg - and record how much to increment by. */ - - if (reg_renumber[regno] >= 0) - regno = reg_renumber[regno]; - if ((regno >= FIRST_PSEUDO_REGISTER - || !(context ? REGNO_OK_FOR_INDEX_P (regno) - : REGNO_OK_FOR_BASE_P (regno)))) - { - register rtx link; - - int reloadnum - = push_reload (x, NULL_RTX, loc, NULL_PTR, - context ? INDEX_REG_CLASS : BASE_REG_CLASS, - GET_MODE (x), GET_MODE (x), VOIDmode, 0, - opnum, type); - reload_inc[reloadnum] - = find_inc_amount (PATTERN (this_insn), XEXP (x_orig, 0)); - - value = 1; - -#ifdef AUTO_INC_DEC - /* Update the REG_INC notes. */ - - for (link = REG_NOTES (this_insn); - link; link = XEXP (link, 1)) - if (REG_NOTE_KIND (link) == REG_INC - && REGNO (XEXP (link, 0)) == REGNO (XEXP (x_orig, 0))) - push_replacement (&XEXP (link, 0), reloadnum, VOIDmode); -#endif - } - return value; - } - else if (GET_CODE (XEXP (x, 0)) == MEM) - { - /* This is probably the result of a substitution, by eliminate_regs, - of an equivalent address for a pseudo that was not allocated to a - hard register. Verify that the specified address is valid and - reload it into a register. */ - rtx tem = XEXP (x, 0); - register rtx link; - int reloadnum; - - /* Since we know we are going to reload this item, don't decrement - for the indirection level. - - Note that this is actually conservative: it would be slightly - more efficient to use the value of SPILL_INDIRECT_LEVELS from - reload1.c here. */ - find_reloads_address (GET_MODE (x), &XEXP (x, 0), - XEXP (XEXP (x, 0), 0), &XEXP (XEXP (x, 0), 0), - opnum, type, ind_levels); - - reloadnum = push_reload (x, NULL_RTX, loc, NULL_PTR, - context ? INDEX_REG_CLASS : BASE_REG_CLASS, - GET_MODE (x), VOIDmode, 0, 0, opnum, type); - reload_inc[reloadnum] - = find_inc_amount (PATTERN (this_insn), XEXP (x, 0)); - - link = FIND_REG_INC_NOTE (this_insn, tem); - if (link != 0) - push_replacement (&XEXP (link, 0), reloadnum, VOIDmode); - - return 1; - } - } - else if (code == MEM) - { - /* This is probably the result of a substitution, by eliminate_regs, - of an equivalent address for a pseudo that was not allocated to a - hard register. Verify that the specified address is valid and reload - it into a register. - - Since we know we are going to reload this item, don't decrement - for the indirection level. - - Note that this is actually conservative: it would be slightly more - efficient to use the value of SPILL_INDIRECT_LEVELS from - reload1.c here. */ - - find_reloads_address (GET_MODE (x), loc, XEXP (x, 0), &XEXP (x, 0), - opnum, type, ind_levels); - - push_reload (*loc, NULL_RTX, loc, NULL_PTR, - context ? INDEX_REG_CLASS : BASE_REG_CLASS, - GET_MODE (x), VOIDmode, 0, 0, opnum, type); - return 1; - } - else if (code == REG) - { - register int regno = REGNO (x); - - if (reg_equiv_constant[regno] != 0) - { - find_reloads_address_part (reg_equiv_constant[regno], loc, - (context ? INDEX_REG_CLASS - : BASE_REG_CLASS), - GET_MODE (x), opnum, type, ind_levels); - return 1; - } - -#if 0 /* This might screw code in reload1.c to delete prior output-reload - that feeds this insn. */ - if (reg_equiv_mem[regno] != 0) - { - push_reload (reg_equiv_mem[regno], NULL_RTX, loc, NULL_PTR, - context ? INDEX_REG_CLASS : BASE_REG_CLASS, - GET_MODE (x), VOIDmode, 0, 0, opnum, type); - return 1; - } -#endif - if (reg_equiv_address[regno] != 0) - { - x = make_memloc (x, regno); - find_reloads_address (GET_MODE (x), 0, XEXP (x, 0), &XEXP (x, 0), - opnum, type, ind_levels); - } - - if (reg_renumber[regno] >= 0) - regno = reg_renumber[regno]; - if ((regno >= FIRST_PSEUDO_REGISTER - || !(context ? REGNO_OK_FOR_INDEX_P (regno) - : REGNO_OK_FOR_BASE_P (regno)))) - { - push_reload (x, NULL_RTX, loc, NULL_PTR, - context ? INDEX_REG_CLASS : BASE_REG_CLASS, - GET_MODE (x), VOIDmode, 0, 0, opnum, type); - return 1; - } - - /* If a register appearing in an address is the subject of a CLOBBER - in this insn, reload it into some other register to be safe. - The CLOBBER is supposed to make the register unavailable - from before this insn to after it. */ - if (regno_clobbered_p (regno, this_insn)) - { - push_reload (x, NULL_RTX, loc, NULL_PTR, - context ? INDEX_REG_CLASS : BASE_REG_CLASS, - GET_MODE (x), VOIDmode, 0, 0, opnum, type); - return 1; - } - } - else - { - register char *fmt = GET_RTX_FORMAT (code); - register int i; - for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - { - if (fmt[i] == 'e') - find_reloads_address_1 (XEXP (x, i), context, &XEXP (x, i), - opnum, type, ind_levels); - } - } - - return 0; -} - -/* X, which is found at *LOC, is a part of an address that needs to be - reloaded into a register of class CLASS. If X is a constant, or if - X is a PLUS that contains a constant, check that the constant is a - legitimate operand and that we are supposed to be able to load - it into the register. - - If not, force the constant into memory and reload the MEM instead. - - MODE is the mode to use, in case X is an integer constant. - - OPNUM and TYPE describe the purpose of any reloads made. - - IND_LEVELS says how many levels of indirect addressing this machine - supports. */ - -static void -find_reloads_address_part (x, loc, class, mode, opnum, type, ind_levels) - rtx x; - rtx *loc; - enum reg_class class; - enum machine_mode mode; - int opnum; - enum reload_type type; - int ind_levels; -{ - if (CONSTANT_P (x) - && (! LEGITIMATE_CONSTANT_P (x) - || PREFERRED_RELOAD_CLASS (x, class) == NO_REGS)) - { - rtx tem = x = force_const_mem (mode, x); - find_reloads_address (mode, &tem, XEXP (tem, 0), &XEXP (tem, 0), - opnum, type, ind_levels); - } - - else if (GET_CODE (x) == PLUS - && CONSTANT_P (XEXP (x, 1)) - && (! LEGITIMATE_CONSTANT_P (XEXP (x, 1)) - || PREFERRED_RELOAD_CLASS (XEXP (x, 1), class) == NO_REGS)) - { - rtx tem = force_const_mem (GET_MODE (x), XEXP (x, 1)); - - x = gen_rtx (PLUS, GET_MODE (x), XEXP (x, 0), tem); - find_reloads_address (mode, &tem, XEXP (tem, 0), &XEXP (tem, 0), - opnum, type, ind_levels); - } - - push_reload (x, NULL_RTX, loc, NULL_PTR, class, - mode, VOIDmode, 0, 0, opnum, type); -} - -/* Substitute into the current INSN the registers into which we have reloaded - the things that need reloading. The array `replacements' - says contains the locations of all pointers that must be changed - and says what to replace them with. - - Return the rtx that X translates into; usually X, but modified. */ - -void -subst_reloads () -{ - register int i; - - for (i = 0; i < n_replacements; i++) - { - register struct replacement *r = &replacements[i]; - register rtx reloadreg = reload_reg_rtx[r->what]; - if (reloadreg) - { - /* Encapsulate RELOADREG so its machine mode matches what - used to be there. */ - if (GET_MODE (reloadreg) != r->mode && r->mode != VOIDmode) - reloadreg = gen_lowpart_common (r->mode, reloadreg); - - /* If we are putting this into a SUBREG and RELOADREG is a - SUBREG, we would be making nested SUBREGs, so we have to fix - this up. Note that r->where == &SUBREG_REG (*r->subreg_loc). */ - - if (r->subreg_loc != 0 && GET_CODE (reloadreg) == SUBREG) - { - if (GET_MODE (*r->subreg_loc) - == GET_MODE (SUBREG_REG (reloadreg))) - *r->subreg_loc = SUBREG_REG (reloadreg); - else - { - *r->where = SUBREG_REG (reloadreg); - SUBREG_WORD (*r->subreg_loc) += SUBREG_WORD (reloadreg); - } - } - else - *r->where = reloadreg; - } - /* If reload got no reg and isn't optional, something's wrong. */ - else if (! reload_optional[r->what]) - abort (); - } -} - -/* Make a copy of any replacements being done into X and move those copies - to locations in Y, a copy of X. We only look at the highest level of - the RTL. */ - -void -copy_replacements (x, y) - rtx x; - rtx y; -{ - int i, j; - enum rtx_code code = GET_CODE (x); - char *fmt = GET_RTX_FORMAT (code); - struct replacement *r; - - /* We can't support X being a SUBREG because we might then need to know its - location if something inside it was replaced. */ - if (code == SUBREG) - abort (); - - for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - if (fmt[i] == 'e') - for (j = 0; j < n_replacements; j++) - { - if (replacements[j].subreg_loc == &XEXP (x, i)) - { - r = &replacements[n_replacements++]; - r->where = replacements[j].where; - r->subreg_loc = &XEXP (y, i); - r->what = replacements[j].what; - r->mode = replacements[j].mode; - } - else if (replacements[j].where == &XEXP (x, i)) - { - r = &replacements[n_replacements++]; - r->where = &XEXP (y, i); - r->subreg_loc = 0; - r->what = replacements[j].what; - r->mode = replacements[j].mode; - } - } -} - -/* If LOC was scheduled to be replaced by something, return the replacement. - Otherwise, return *LOC. */ - -rtx -find_replacement (loc) - rtx *loc; -{ - struct replacement *r; - - for (r = &replacements[0]; r < &replacements[n_replacements]; r++) - { - rtx reloadreg = reload_reg_rtx[r->what]; - - if (reloadreg && r->where == loc) - { - if (r->mode != VOIDmode && GET_MODE (reloadreg) != r->mode) - reloadreg = gen_rtx (REG, r->mode, REGNO (reloadreg)); - - return reloadreg; - } - else if (reloadreg && r->subreg_loc == loc) - { - /* RELOADREG must be either a REG or a SUBREG. - - ??? Is it actually still ever a SUBREG? If so, why? */ - - if (GET_CODE (reloadreg) == REG) - return gen_rtx (REG, GET_MODE (*loc), - REGNO (reloadreg) + SUBREG_WORD (*loc)); - else if (GET_MODE (reloadreg) == GET_MODE (*loc)) - return reloadreg; - else - return gen_rtx (SUBREG, GET_MODE (*loc), SUBREG_REG (reloadreg), - SUBREG_WORD (reloadreg) + SUBREG_WORD (*loc)); - } - } - - return *loc; -} - -/* Return nonzero if register in range [REGNO, ENDREGNO) - appears either explicitly or implicitly in X - other than being stored into. - - References contained within the substructure at LOC do not count. - LOC may be zero, meaning don't ignore anything. - - This is similar to refers_to_regno_p in rtlanal.c except that we - look at equivalences for pseudos that didn't get hard registers. */ - -int -refers_to_regno_for_reload_p (regno, endregno, x, loc) - int regno, endregno; - rtx x; - rtx *loc; -{ - register int i; - register RTX_CODE code; - register char *fmt; - - if (x == 0) - return 0; - - repeat: - code = GET_CODE (x); - - switch (code) - { - case REG: - i = REGNO (x); - - /* If this is a pseudo, a hard register must not have been allocated. - X must therefore either be a constant or be in memory. */ - if (i >= FIRST_PSEUDO_REGISTER) - { - if (reg_equiv_memory_loc[i]) - return refers_to_regno_for_reload_p (regno, endregno, - reg_equiv_memory_loc[i], - NULL_PTR); - - if (reg_equiv_constant[i]) - return 0; - - abort (); - } - - return (endregno > i - && regno < i + (i < FIRST_PSEUDO_REGISTER - ? HARD_REGNO_NREGS (i, GET_MODE (x)) - : 1)); - - case SUBREG: - /* If this is a SUBREG of a hard reg, we can see exactly which - registers are being modified. Otherwise, handle normally. */ - if (GET_CODE (SUBREG_REG (x)) == REG - && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER) - { - int inner_regno = REGNO (SUBREG_REG (x)) + SUBREG_WORD (x); - int inner_endregno - = inner_regno + (inner_regno < FIRST_PSEUDO_REGISTER - ? HARD_REGNO_NREGS (regno, GET_MODE (x)) : 1); - - return endregno > inner_regno && regno < inner_endregno; - } - break; - - case CLOBBER: - case SET: - if (&SET_DEST (x) != loc - /* Note setting a SUBREG counts as referring to the REG it is in for - a pseudo but not for hard registers since we can - treat each word individually. */ - && ((GET_CODE (SET_DEST (x)) == SUBREG - && loc != &SUBREG_REG (SET_DEST (x)) - && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG - && REGNO (SUBREG_REG (SET_DEST (x))) >= FIRST_PSEUDO_REGISTER - && refers_to_regno_for_reload_p (regno, endregno, - SUBREG_REG (SET_DEST (x)), - loc)) - || (GET_CODE (SET_DEST (x)) != REG - && refers_to_regno_for_reload_p (regno, endregno, - SET_DEST (x), loc)))) - return 1; - - if (code == CLOBBER || loc == &SET_SRC (x)) - return 0; - x = SET_SRC (x); - goto repeat; - } - - /* X does not match, so try its subexpressions. */ - - fmt = GET_RTX_FORMAT (code); - for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - { - if (fmt[i] == 'e' && loc != &XEXP (x, i)) - { - if (i == 0) - { - x = XEXP (x, 0); - goto repeat; - } - else - if (refers_to_regno_for_reload_p (regno, endregno, - XEXP (x, i), loc)) - return 1; - } - else if (fmt[i] == 'E') - { - register int j; - for (j = XVECLEN (x, i) - 1; j >=0; j--) - if (loc != &XVECEXP (x, i, j) - && refers_to_regno_for_reload_p (regno, endregno, - XVECEXP (x, i, j), loc)) - return 1; - } - } - return 0; -} - -/* Nonzero if modifying X will affect IN. If X is a register or a SUBREG, - we check if any register number in X conflicts with the relevant register - numbers. If X is a constant, return 0. If X is a MEM, return 1 iff IN - contains a MEM (we don't bother checking for memory addresses that can't - conflict because we expect this to be a rare case. - - This function is similar to reg_overlap_mention_p in rtlanal.c except - that we look at equivalences for pseudos that didn't get hard registers. */ - -int -reg_overlap_mentioned_for_reload_p (x, in) - rtx x, in; -{ - int regno, endregno; - - if (GET_CODE (x) == SUBREG) - { - regno = REGNO (SUBREG_REG (x)); - if (regno < FIRST_PSEUDO_REGISTER) - regno += SUBREG_WORD (x); - } - else if (GET_CODE (x) == REG) - { - regno = REGNO (x); - - /* If this is a pseudo, it must not have been assigned a hard register. - Therefore, it must either be in memory or be a constant. */ - - if (regno >= FIRST_PSEUDO_REGISTER) - { - if (reg_equiv_memory_loc[regno]) - return refers_to_mem_for_reload_p (in); - else if (reg_equiv_constant[regno]) - return 0; - abort (); - } - } - else if (CONSTANT_P (x)) - return 0; - else if (GET_CODE (x) == MEM) - return refers_to_mem_for_reload_p (in); - else if (GET_CODE (x) == SCRATCH || GET_CODE (x) == PC - || GET_CODE (x) == CC0) - return reg_mentioned_p (x, in); - else - abort (); - - endregno = regno + (regno < FIRST_PSEUDO_REGISTER - ? HARD_REGNO_NREGS (regno, GET_MODE (x)) : 1); - - return refers_to_regno_for_reload_p (regno, endregno, in, NULL_PTR); -} - -/* Return nonzero if anything in X contains a MEM. Look also for pseudo - registers. */ - -int -refers_to_mem_for_reload_p (x) - rtx x; -{ - char *fmt; - int i; - - if (GET_CODE (x) == MEM) - return 1; - - if (GET_CODE (x) == REG) - return (REGNO (x) >= FIRST_PSEUDO_REGISTER - && reg_equiv_memory_loc[REGNO (x)]); - - fmt = GET_RTX_FORMAT (GET_CODE (x)); - for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--) - if (fmt[i] == 'e' - && (GET_CODE (XEXP (x, i)) == MEM - || refers_to_mem_for_reload_p (XEXP (x, i)))) - return 1; - - return 0; -} - -/* Check the insns before INSN to see if there is a suitable register - containing the same value as GOAL. - If OTHER is -1, look for a register in class CLASS. - Otherwise, just see if register number OTHER shares GOAL's value. - - Return an rtx for the register found, or zero if none is found. - - If RELOAD_REG_P is (short *)1, - we reject any hard reg that appears in reload_reg_rtx - because such a hard reg is also needed coming into this insn. - - If RELOAD_REG_P is any other nonzero value, - it is a vector indexed by hard reg number - and we reject any hard reg whose element in the vector is nonnegative - as well as any that appears in reload_reg_rtx. - - If GOAL is zero, then GOALREG is a register number; we look - for an equivalent for that register. - - MODE is the machine mode of the value we want an equivalence for. - If GOAL is nonzero and not VOIDmode, then it must have mode MODE. - - This function is used by jump.c as well as in the reload pass. - - If GOAL is the sum of the stack pointer and a constant, we treat it - as if it were a constant except that sp is required to be unchanging. */ - -rtx -find_equiv_reg (goal, insn, class, other, reload_reg_p, goalreg, mode) - register rtx goal; - rtx insn; - enum reg_class class; - register int other; - short *reload_reg_p; - int goalreg; - enum machine_mode mode; -{ - register rtx p = insn; - rtx goaltry, valtry, value, where; - register rtx pat; - register int regno = -1; - int valueno; - int goal_mem = 0; - int goal_const = 0; - int goal_mem_addr_varies = 0; - int need_stable_sp = 0; - int nregs; - int valuenregs; - - if (goal == 0) - regno = goalreg; - else if (GET_CODE (goal) == REG) - regno = REGNO (goal); - else if (GET_CODE (goal) == MEM) - { - enum rtx_code code = GET_CODE (XEXP (goal, 0)); - if (MEM_VOLATILE_P (goal)) - return 0; - if (flag_float_store && GET_MODE_CLASS (GET_MODE (goal)) == MODE_FLOAT) - return 0; - /* An address with side effects must be reexecuted. */ - switch (code) - { - case POST_INC: - case PRE_INC: - case POST_DEC: - case PRE_DEC: - return 0; - } - goal_mem = 1; - } - else if (CONSTANT_P (goal)) - goal_const = 1; - else if (GET_CODE (goal) == PLUS - && XEXP (goal, 0) == stack_pointer_rtx - && CONSTANT_P (XEXP (goal, 1))) - goal_const = need_stable_sp = 1; - else - return 0; - - /* On some machines, certain regs must always be rejected - because they don't behave the way ordinary registers do. */ - -#ifdef OVERLAPPING_REGNO_P - if (regno >= 0 && regno < FIRST_PSEUDO_REGISTER - && OVERLAPPING_REGNO_P (regno)) - return 0; -#endif - - /* Scan insns back from INSN, looking for one that copies - a value into or out of GOAL. - Stop and give up if we reach a label. */ - - while (1) - { - p = PREV_INSN (p); - if (p == 0 || GET_CODE (p) == CODE_LABEL) - return 0; - if (GET_CODE (p) == INSN - /* If we don't want spill regs ... */ - && (! (reload_reg_p != 0 - && reload_reg_p != (short *) (HOST_WIDE_INT) 1) - /* ... then ignore insns introduced by reload; they aren't useful - and can cause results in reload_as_needed to be different - from what they were when calculating the need for spills. - If we notice an input-reload insn here, we will reject it below, - but it might hide a usable equivalent. That makes bad code. - It may even abort: perhaps no reg was spilled for this insn - because it was assumed we would find that equivalent. */ - || INSN_UID (p) < reload_first_uid)) - { - rtx tem; - pat = single_set (p); - /* First check for something that sets some reg equal to GOAL. */ - if (pat != 0 - && ((regno >= 0 - && true_regnum (SET_SRC (pat)) == regno - && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0) - || - (regno >= 0 - && true_regnum (SET_DEST (pat)) == regno - && (valueno = true_regnum (valtry = SET_SRC (pat))) >= 0) - || - (goal_const && rtx_equal_p (SET_SRC (pat), goal) - && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0) - || (goal_mem - && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0 - && rtx_renumbered_equal_p (goal, SET_SRC (pat))) - || (goal_mem - && (valueno = true_regnum (valtry = SET_SRC (pat))) >= 0 - && rtx_renumbered_equal_p (goal, SET_DEST (pat))) - /* If we are looking for a constant, - and something equivalent to that constant was copied - into a reg, we can use that reg. */ - || (goal_const && (tem = find_reg_note (p, REG_EQUIV, - NULL_RTX)) - && rtx_equal_p (XEXP (tem, 0), goal) - && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0) - || (goal_const && (tem = find_reg_note (p, REG_EQUIV, - NULL_RTX)) - && GET_CODE (SET_DEST (pat)) == REG - && GET_CODE (XEXP (tem, 0)) == CONST_DOUBLE - && GET_MODE_CLASS (GET_MODE (XEXP (tem, 0))) == MODE_FLOAT - && GET_CODE (goal) == CONST_INT - && 0 != (goaltry = operand_subword (XEXP (tem, 0), 0, 0, - VOIDmode)) - && rtx_equal_p (goal, goaltry) - && (valtry = operand_subword (SET_DEST (pat), 0, 0, - VOIDmode)) - && (valueno = true_regnum (valtry)) >= 0) - || (goal_const && (tem = find_reg_note (p, REG_EQUIV, - NULL_RTX)) - && GET_CODE (SET_DEST (pat)) == REG - && GET_CODE (XEXP (tem, 0)) == CONST_DOUBLE - && GET_MODE_CLASS (GET_MODE (XEXP (tem, 0))) == MODE_FLOAT - && GET_CODE (goal) == CONST_INT - && 0 != (goaltry = operand_subword (XEXP (tem, 0), 1, 0, - VOIDmode)) - && rtx_equal_p (goal, goaltry) - && (valtry - = operand_subword (SET_DEST (pat), 1, 0, VOIDmode)) - && (valueno = true_regnum (valtry)) >= 0))) - if (other >= 0 - ? valueno == other - : ((unsigned) valueno < FIRST_PSEUDO_REGISTER - && TEST_HARD_REG_BIT (reg_class_contents[(int) class], - valueno))) - { - value = valtry; - where = p; - break; - } - } - } - - /* We found a previous insn copying GOAL into a suitable other reg VALUE - (or copying VALUE into GOAL, if GOAL is also a register). - Now verify that VALUE is really valid. */ - - /* VALUENO is the register number of VALUE; a hard register. */ - - /* Don't try to re-use something that is killed in this insn. We want - to be able to trust REG_UNUSED notes. */ - if (find_reg_note (where, REG_UNUSED, value)) - return 0; - - /* If we propose to get the value from the stack pointer or if GOAL is - a MEM based on the stack pointer, we need a stable SP. */ - if (valueno == STACK_POINTER_REGNUM - || (goal_mem && reg_overlap_mentioned_for_reload_p (stack_pointer_rtx, - goal))) - need_stable_sp = 1; - - /* Reject VALUE if the copy-insn moved the wrong sort of datum. */ - if (GET_MODE (value) != mode) - return 0; - - /* Reject VALUE if it was loaded from GOAL - and is also a register that appears in the address of GOAL. */ - - if (goal_mem && value == SET_DEST (PATTERN (where)) - && refers_to_regno_for_reload_p (valueno, - (valueno - + HARD_REGNO_NREGS (valueno, mode)), - goal, NULL_PTR)) - return 0; - - /* Reject registers that overlap GOAL. */ - - if (!goal_mem && !goal_const - && regno + HARD_REGNO_NREGS (regno, mode) > valueno - && regno < valueno + HARD_REGNO_NREGS (valueno, mode)) - return 0; - - /* Reject VALUE if it is one of the regs reserved for reloads. - Reload1 knows how to reuse them anyway, and it would get - confused if we allocated one without its knowledge. - (Now that insns introduced by reload are ignored above, - this case shouldn't happen, but I'm not positive.) */ - - if (reload_reg_p != 0 && reload_reg_p != (short *) (HOST_WIDE_INT) 1 - && reload_reg_p[valueno] >= 0) - return 0; - - /* On some machines, certain regs must always be rejected - because they don't behave the way ordinary registers do. */ - -#ifdef OVERLAPPING_REGNO_P - if (OVERLAPPING_REGNO_P (valueno)) - return 0; -#endif - - nregs = HARD_REGNO_NREGS (regno, mode); - valuenregs = HARD_REGNO_NREGS (valueno, mode); - - /* Reject VALUE if it is a register being used for an input reload - even if it is not one of those reserved. */ - - if (reload_reg_p != 0) - { - int i; - for (i = 0; i < n_reloads; i++) - if (reload_reg_rtx[i] != 0 && reload_in[i]) - { - int regno1 = REGNO (reload_reg_rtx[i]); - int nregs1 = HARD_REGNO_NREGS (regno1, - GET_MODE (reload_reg_rtx[i])); - if (regno1 < valueno + valuenregs - && regno1 + nregs1 > valueno) - return 0; - } - } - - if (goal_mem) - /* We must treat frame pointer as varying here, - since it can vary--in a nonlocal goto as generated by expand_goto. */ - goal_mem_addr_varies = !CONSTANT_ADDRESS_P (XEXP (goal, 0)); - - /* Now verify that the values of GOAL and VALUE remain unaltered - until INSN is reached. */ - - p = insn; - while (1) - { - p = PREV_INSN (p); - if (p == where) - return value; - - /* Don't trust the conversion past a function call - if either of the two is in a call-clobbered register, or memory. */ - if (GET_CODE (p) == CALL_INSN - && ((regno >= 0 && regno < FIRST_PSEUDO_REGISTER - && call_used_regs[regno]) - || - (valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER - && call_used_regs[valueno]) - || - goal_mem - || need_stable_sp)) - return 0; - -#ifdef INSN_CLOBBERS_REGNO_P - if ((valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER - && INSN_CLOBBERS_REGNO_P (p, valueno)) - || (regno >= 0 && regno < FIRST_PSEUDO_REGISTER - && INSN_CLOBBERS_REGNO_P (p, regno))) - return 0; -#endif - - if (GET_RTX_CLASS (GET_CODE (p)) == 'i') - { - /* If this insn P stores in either GOAL or VALUE, return 0. - If GOAL is a memory ref and this insn writes memory, return 0. - If GOAL is a memory ref and its address is not constant, - and this insn P changes a register used in GOAL, return 0. */ - - pat = PATTERN (p); - if (GET_CODE (pat) == SET || GET_CODE (pat) == CLOBBER) - { - register rtx dest = SET_DEST (pat); - while (GET_CODE (dest) == SUBREG - || GET_CODE (dest) == ZERO_EXTRACT - || GET_CODE (dest) == SIGN_EXTRACT - || GET_CODE (dest) == STRICT_LOW_PART) - dest = XEXP (dest, 0); - if (GET_CODE (dest) == REG) - { - register int xregno = REGNO (dest); - int xnregs; - if (REGNO (dest) < FIRST_PSEUDO_REGISTER) - xnregs = HARD_REGNO_NREGS (xregno, GET_MODE (dest)); - else - xnregs = 1; - if (xregno < regno + nregs && xregno + xnregs > regno) - return 0; - if (xregno < valueno + valuenregs - && xregno + xnregs > valueno) - return 0; - if (goal_mem_addr_varies - && reg_overlap_mentioned_for_reload_p (dest, goal)) - return 0; - } - else if (goal_mem && GET_CODE (dest) == MEM - && ! push_operand (dest, GET_MODE (dest))) - return 0; - else if (need_stable_sp && push_operand (dest, GET_MODE (dest))) - return 0; - } - else if (GET_CODE (pat) == PARALLEL) - { - register int i; - for (i = XVECLEN (pat, 0) - 1; i >= 0; i--) - { - register rtx v1 = XVECEXP (pat, 0, i); - if (GET_CODE (v1) == SET || GET_CODE (v1) == CLOBBER) - { - register rtx dest = SET_DEST (v1); - while (GET_CODE (dest) == SUBREG - || GET_CODE (dest) == ZERO_EXTRACT - || GET_CODE (dest) == SIGN_EXTRACT - || GET_CODE (dest) == STRICT_LOW_PART) - dest = XEXP (dest, 0); - if (GET_CODE (dest) == REG) - { - register int xregno = REGNO (dest); - int xnregs; - if (REGNO (dest) < FIRST_PSEUDO_REGISTER) - xnregs = HARD_REGNO_NREGS (xregno, GET_MODE (dest)); - else - xnregs = 1; - if (xregno < regno + nregs - && xregno + xnregs > regno) - return 0; - if (xregno < valueno + valuenregs - && xregno + xnregs > valueno) - return 0; - if (goal_mem_addr_varies - && reg_overlap_mentioned_for_reload_p (dest, - goal)) - return 0; - } - else if (goal_mem && GET_CODE (dest) == MEM - && ! push_operand (dest, GET_MODE (dest))) - return 0; - else if (need_stable_sp - && push_operand (dest, GET_MODE (dest))) - return 0; - } - } - } - -#ifdef AUTO_INC_DEC - /* If this insn auto-increments or auto-decrements - either regno or valueno, return 0 now. - If GOAL is a memory ref and its address is not constant, - and this insn P increments a register used in GOAL, return 0. */ - { - register rtx link; - - for (link = REG_NOTES (p); link; link = XEXP (link, 1)) - if (REG_NOTE_KIND (link) == REG_INC - && GET_CODE (XEXP (link, 0)) == REG) - { - register int incno = REGNO (XEXP (link, 0)); - if (incno < regno + nregs && incno >= regno) - return 0; - if (incno < valueno + valuenregs && incno >= valueno) - return 0; - if (goal_mem_addr_varies - && reg_overlap_mentioned_for_reload_p (XEXP (link, 0), - goal)) - return 0; - } - } -#endif - } - } -} - -/* Find a place where INCED appears in an increment or decrement operator - within X, and return the amount INCED is incremented or decremented by. - The value is always positive. */ - -static int -find_inc_amount (x, inced) - rtx x, inced; -{ - register enum rtx_code code = GET_CODE (x); - register char *fmt; - register int i; - - if (code == MEM) - { - register rtx addr = XEXP (x, 0); - if ((GET_CODE (addr) == PRE_DEC - || GET_CODE (addr) == POST_DEC - || GET_CODE (addr) == PRE_INC - || GET_CODE (addr) == POST_INC) - && XEXP (addr, 0) == inced) - return GET_MODE_SIZE (GET_MODE (x)); - } - - fmt = GET_RTX_FORMAT (code); - for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - { - if (fmt[i] == 'e') - { - register int tem = find_inc_amount (XEXP (x, i), inced); - if (tem != 0) - return tem; - } - if (fmt[i] == 'E') - { - register int j; - for (j = XVECLEN (x, i) - 1; j >= 0; j--) - { - register int tem = find_inc_amount (XVECEXP (x, i, j), inced); - if (tem != 0) - return tem; - } - } - } - - return 0; -} - -/* Return 1 if register REGNO is the subject of a clobber in insn INSN. */ - -int -regno_clobbered_p (regno, insn) - int regno; - rtx insn; -{ - if (GET_CODE (PATTERN (insn)) == CLOBBER - && GET_CODE (XEXP (PATTERN (insn), 0)) == REG) - return REGNO (XEXP (PATTERN (insn), 0)) == regno; - - if (GET_CODE (PATTERN (insn)) == PARALLEL) - { - int i = XVECLEN (PATTERN (insn), 0) - 1; - - for (; i >= 0; i--) - { - rtx elt = XVECEXP (PATTERN (insn), 0, i); - if (GET_CODE (elt) == CLOBBER && GET_CODE (XEXP (elt, 0)) == REG - && REGNO (XEXP (elt, 0)) == regno) - return 1; - } - } - - return 0; -} |