diff options
Diffstat (limited to 'contrib/llvm-project/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c')
| -rw-r--r-- | contrib/llvm-project/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c b/contrib/llvm-project/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c new file mode 100644 index 000000000000..b9d51b698b41 --- /dev/null +++ b/contrib/llvm-project/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c @@ -0,0 +1,221 @@ +/*===- InstrProfilingPlatformAIX.c - Profile data AIX platform ------------===*\ +|* +|* Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +|* See https://llvm.org/LICENSE.txt for license information. +|* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +|* +\*===----------------------------------------------------------------------===*/ + +#if defined(_AIX) + +#ifdef __64BIT__ +#define __XCOFF64__ +#endif +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ldr.h> +#include <xcoff.h> + +#include "InstrProfiling.h" +#include "InstrProfilingInternal.h" + +#define BIN_ID_PREFIX "xcoff_binary_id:" + +// If found, write the build-id into the Result buffer. +static size_t FindBinaryId(char *Result, size_t Size) { + unsigned long EntryAddr = (unsigned long)__builtin_return_address(0); + + // Use loadquery to get information about loaded modules; loadquery writes + // its result into a buffer of unknown size. + char Buf[1024]; + size_t BufSize = sizeof(Buf); + char *BufPtr = Buf; + int RC = -1; + + errno = 0; + RC = loadquery(L_GETXINFO | L_IGNOREUNLOAD, BufPtr, (unsigned int)BufSize); + if (RC == -1 && errno == ENOMEM) { + BufSize = 64000; // should be plenty for any program. + BufPtr = malloc(BufSize); + if (BufPtr != 0) + RC = loadquery(L_GETXINFO | L_IGNOREUNLOAD, BufPtr, (unsigned int)BufSize); + } + + if (RC == -1) + goto done; + + // Locate the ld_xinfo corresponding to this module. + struct ld_xinfo *CurInfo = (struct ld_xinfo *)BufPtr; + while (1) { + unsigned long CurTextStart = (uint64_t)CurInfo->ldinfo_textorg; + unsigned long CurTextEnd = CurTextStart + CurInfo->ldinfo_textsize; + if (CurTextStart <= EntryAddr && EntryAddr < CurTextEnd) { + // Found my slot. Now search for the build-id. + char *p = (char *)CurInfo->ldinfo_textorg; + + FILHDR *f = (FILHDR *)p; + AOUTHDR *a = (AOUTHDR *)(p + FILHSZ); + SCNHDR *s = + (SCNHDR *)(p + FILHSZ + f->f_opthdr + SCNHSZ * (a->o_snloader - 1)); + LDHDR *ldhdr = (LDHDR *)(p + s->s_scnptr); + // This is the loader string table + char *lstr = (char *)ldhdr + ldhdr->l_stoff; + + // If the build-id exists, it's the first entry. + // Each entry is comprised of a 2-byte size component, followed by the + // data. + size_t len = *(short *)lstr; + char *str = (char *)(lstr + 2); + size_t PrefixLen = sizeof(BIN_ID_PREFIX) - 1; + if (len > PrefixLen && (len - PrefixLen) <= Size && + strncmp(str, BIN_ID_PREFIX, PrefixLen) == 0) { + memcpy(Result, str + PrefixLen, len - PrefixLen); + RC = len - PrefixLen; + goto done; + } + break; + } + if (CurInfo->ldinfo_next == 0u) + break; + CurInfo = (struct ld_xinfo *)((char *)CurInfo + CurInfo->ldinfo_next); + } +done: + if (BufSize != sizeof(Buf) && BufPtr != 0) + free(BufPtr); + return RC; +} + +static int StrToHexError = 0; +static uint8_t StrToHex(char c) { + if (c >= '0' && c <= '9') + return c - '0'; + if (c >= 'a' && c <= 'f') + return c - 'a' + 0xa; + if (c >= 'A' && c <= 'F') + return c - 'A' + 0xa; + StrToHexError = 1; + return 0; +} + +COMPILER_RT_VISIBILITY int __llvm_write_binary_ids(ProfDataWriter *Writer) { + // 200 bytes should be enough for the build-id hex string. + static char Buf[200]; + // Profile reading tools expect this to be 8-bytes long. + static int64_t BinaryIdLen = 0; + static uint8_t *BinaryIdData = 0; + + // -1 means we already checked for a BinaryId and didn't find one. + if (BinaryIdLen == -1) + return 0; + + // Are we being called for the first time? + if (BinaryIdLen == 0) { + if (getenv("LLVM_PROFILE_NO_BUILD_ID")) + goto fail; + + int BuildIdLen = FindBinaryId(Buf, sizeof(Buf)); + if (BuildIdLen <= 0) + goto fail; + + if (Buf[BuildIdLen - 1] == '\0') + BuildIdLen--; + + // assume even number of digits/chars, so 0xabc must be 0x0abc + if ((BuildIdLen % 2) != 0 || BuildIdLen == 0) + goto fail; + + // The numeric ID is represented as an ascii string in the loader section, + // so convert it to raw binary. + BinaryIdLen = BuildIdLen / 2; + BinaryIdData = (uint8_t *)Buf; + + // Skip "0x" prefix if it exists. + if (Buf[0] == '0' && Buf[1] == 'x') { + BinaryIdLen -= 1; + BinaryIdData += 2; + } + + StrToHexError = 0; + for (int i = 0; i < BinaryIdLen; i++) + BinaryIdData[i] = (StrToHex(BinaryIdData[2 * i]) << 4) + + StrToHex(BinaryIdData[2 * i + 1]); + + if (StrToHexError) + goto fail; + + if (getenv("LLVM_PROFILE_VERBOSE")) { + char *StrBuf = (char *)COMPILER_RT_ALLOCA(2 * BinaryIdLen + 1); + for (int i = 0; i < (int)BinaryIdLen; i++) + sprintf(&StrBuf[2 * i], "%02x", BinaryIdData[i]); + PROF_NOTE("Writing binary id: %s\n", StrBuf); + } + } + + uint8_t BinaryIdPadding = __llvm_profile_get_num_padding_bytes(BinaryIdLen); + if (Writer && lprofWriteOneBinaryId(Writer, BinaryIdLen, BinaryIdData, + BinaryIdPadding) == -1) + return -1; // Return -1 rather goto fail to match the NT_GNU_BUILD_ID path. + + return sizeof(BinaryIdLen) + BinaryIdLen + BinaryIdPadding; + +fail: + if (getenv("LLVM_PROFILE_VERBOSE")) + fprintf(stderr, "no or invalid binary id: %.*s\n", (int)sizeof(Buf), Buf); + BinaryIdLen = -1; + return 0; +} + +// Empty stubs to allow linking object files using the registration-based scheme +COMPILER_RT_VISIBILITY +void __llvm_profile_register_function(void *Data_) {} + +COMPILER_RT_VISIBILITY +void __llvm_profile_register_names_function(void *NamesStart, + uint64_t NamesSize) {} + +// The __start_SECNAME and __stop_SECNAME symbols (for SECNAME \in +// {"__llvm_prf_cnts", "__llvm_prf_data", "__llvm_prf_name", "__llvm_prf_vnds", +// "__llvm_prf_vns", "__llvm_prf_vtab"}) +// are always live when linking on AIX, regardless if the .o's being linked +// reference symbols from the profile library (for example when no files were +// compiled with -fprofile-generate). That's because these symbols are kept +// alive through references in constructor functions that are always live in the +// default linking model on AIX (-bcdtors:all). The __start_SECNAME and +// __stop_SECNAME symbols are only resolved by the linker when the SECNAME +// section exists. So for the scenario where the user objects have no such +// section (i.e. when they are compiled with -fno-profile-generate), we always +// define these zero length variables in each of the above 4 sections. +static int dummy_cnts[0] COMPILER_RT_SECTION( + COMPILER_RT_SEG INSTR_PROF_CNTS_SECT_NAME); +static int dummy_bits[0] COMPILER_RT_SECTION( + COMPILER_RT_SEG INSTR_PROF_BITS_SECT_NAME); +static int dummy_data[0] COMPILER_RT_SECTION( + COMPILER_RT_SEG INSTR_PROF_DATA_SECT_NAME); +static const int dummy_name[0] COMPILER_RT_SECTION( + COMPILER_RT_SEG INSTR_PROF_NAME_SECT_NAME); +static int dummy_vnds[0] COMPILER_RT_SECTION( + COMPILER_RT_SEG INSTR_PROF_VNODES_SECT_NAME); +static int dummy_orderfile[0] COMPILER_RT_SECTION( + COMPILER_RT_SEG INSTR_PROF_ORDERFILE_SECT_NAME); +static int dummy_vname[0] COMPILER_RT_SECTION( + COMPILER_RT_SEG INSTR_PROF_VNAME_SECT_NAME); +static int dummy_vtab[0] COMPILER_RT_SECTION( + COMPILER_RT_SEG INSTR_PROF_VTAB_SECT_NAME); + +// To avoid GC'ing of the dummy variables by the linker, reference them in an +// array and reference the array in the runtime registration code +// (InstrProfilingRuntime.cpp) +#ifdef __GNUC__ +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wcast-qual" +#endif +COMPILER_RT_VISIBILITY +void *__llvm_profile_keep[] = {(void *)&dummy_cnts, (void *)&dummy_bits, + (void *)&dummy_data, (void *)&dummy_name, + (void *)&dummy_vnds, (void *)&dummy_orderfile, + (void *)&dummy_vname, (void *)&dummy_vtab}; +#ifdef __GNUC__ +#pragma GCC diagnostic pop +#endif +#endif |