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Diffstat (limited to 'kernel/arch/hppa/execsp.S')
| -rw-r--r-- | kernel/arch/hppa/execsp.S | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/kernel/arch/hppa/execsp.S b/kernel/arch/hppa/execsp.S new file mode 100644 index 000000000000..520421a1f1fc --- /dev/null +++ b/kernel/arch/hppa/execsp.S @@ -0,0 +1,130 @@ +/* $NetBSD: execsp.S,v 1.1 2025/04/20 22:32:49 riastradh Exp $ */ + +/*- + * Copyright (c) 2025 The NetBSD Foundation, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#define _LOCORE + +#include <machine/asm.h> + +RCSID("$NetBSD: execsp.S,v 1.1 2025/04/20 22:32:49 riastradh Exp $") + + .import _GLOBAL_OFFSET_TABLE_ + +/* + * void execsp_start(struct ps_strings *ps_strings@arg0, + * void (*cleanup@arg1)(void), void *obj_main@arg2) + * + * ELF entry point. Saves the stack pointer in startsp and defers + * to the usual csu __start routine. + */ +LEAF_ENTRY(execsp_start) + /* + * Set up the data pointer (r19) and linkage table register + * (r27) like the real startup routine so we can get at the + * global symbols startsp and __start. + * + * XXX Not really sure why we need to set up r27, since we only + * use r19 here and the real startup routine, __start, will set + * up both r19 and r27 anyway. But this crashes with SIGSEGV + * shortly after startup if we don't set up r27, and gdb + * crashes on my attempts to single-step, so I'll just leave + * the initialization of r27 here for now until someone is + * motivated by the potential for a single-instruction + * micro-optimization in this test program to find out why r27 + * is needed too. + */ + bl L$lpc, %r27 + depi 0, 31, 2, %r27 +L$lpc: addil L'_GLOBAL_OFFSET_TABLE_ - ($PIC_pcrel$0 - 8), %r27 + ldo R'_GLOBAL_OFFSET_TABLE_ - ($PIC_pcrel$0 - 12)(%r1), %r27 + copy %r27, %r19 + + addil LT%_C_LABEL(startsp), %r19 /* r20 := &startsp */ + ldw RT%_C_LABEL(startsp)(%r1), %r20 + + /* PIC_TAILCALL(__start), if we had it */ + addil LT%_C_LABEL(__start), %r19 /* r1 := __start */ + ldw RT%_C_LABEL(__start)(%r1), %r1 + bv %r0(%r1) /* jump to __start */ + stw %sp, 0(%r20) /* startsp := sp */ +EXIT(execsp_start) + +/* + * void execsp_ctor(void) + * + * ELF constructor. Saves the stack pointer in ctorsp and + * returns. + */ +LEAF_ENTRY(execsp_ctor) + addil LT%_C_LABEL(ctorsp), %r19 /* r1 := &ctorsp */ + ldw RT%_C_LABEL(ctorsp)(%r1), %r1 + bv %r0(%rp) /* return */ + stw %sp, 0(%r1) /* ctorsp := sp */ +EXIT(execsp_ctor) + + /* Make execsp_ctor a constructor. */ + .section .ctors,"aw",@progbits + .p2align 2 + .word _C_LABEL(execsp_ctor) + +/* + * int main(int argc@arg0, char **argv@arg1, ...) + * + * Main function. Saves the stack pointer in mainsp and returns + * zero. We will call execsp_main in execsp_dtor once dtorsp has + * been initialized. + */ +LEAF_ENTRY(main) + addil LT%_C_LABEL(mainsp), %r19 /* r1 := &mainsp */ + ldw RT%_C_LABEL(mainsp)(%r1), %r1 + stw %sp, 0(%r1) /* ctorsp := sp */ + bv %r0(%rp) /* return... */ + copy %r0, %ret0 /* ...zero */ +EXIT(main) + +/* + * void execsp_dtor(void) + * + * ELF destructor. Saves the stack pointer in dtorsp and defers + * to the C execsp_main in h_execsp.c to report the stack pointers + * back to the t_signal_and_sp parent. + */ +LEAF_ENTRY(execsp_dtor) + addil LT%_C_LABEL(dtorsp), %r19 /* r20 := &dtorsp */ + ldw RT%_C_LABEL(dtorsp)(%r1), %r20 + + /* PIC_TAILCALL(__start), if we had it */ + addil LT%_C_LABEL(execsp_main), %r19 /* r1 := execsp_main */ + ldw RT%_C_LABEL(execsp_main)(%r1), %r1 + bv %r0(%r1) /* jump to execsp_main */ + stw %sp, 0(%r20) /* startsp := sp */ +EXIT(execsp_dtor) + + /* Make execsp_ctor a destructor. */ + .section .dtors,"aw",@progbits + .p2align 2 + .word _C_LABEL(execsp_dtor) |