From: Vladimir Mezentsev Date: Wed, 20 Sep 2023 20:22:12 +0000 (-0700) Subject: gprofng: 30834 improve disassembly output for call and branch instructions X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=7434de7ef9aef6307de8cb8244ca27a67dc99245;p=binutils-gdb.git gprofng: 30834 improve disassembly output for call and branch instructions This patch makes the gprofng disassembler to emit, e.g. call fprintf@plt [ 0x401060, .-0x49c] instead of call 0xfffffffffffffb64 I use bfd_get_synthetic_symtab() to get function names in the .plt section. I have not yet modified Elf-reader in gprofng to remove parsing of .symtab or .dynsym sections. But we plan to do it. gprofng/ChangeLog 2023-09-20 Vladimir Mezentsev PR gprofng/30834 * src/Disasm.cc: Show the function name in the call instruction and the relative address in the branch instruction. Remove unused code. * src/Disasm.h (map_PC_to_func, get_funcname_in_plt): New functions. * src/Elf.cc: Get function names for the .plt section. * src/Elf.h (get_funcname_in_plt, get_bfd_symbols): New functions. * src/Stabs.cc: Add pltSym to SymLst. Remove the conversion to uint32_t. --- diff --git a/gprofng/src/Disasm.cc b/gprofng/src/Disasm.cc index ef1ef7c9d9f..9c7e59a590b 100644 --- a/gprofng/src/Disasm.cc +++ b/gprofng/src/Disasm.cc @@ -34,6 +34,7 @@ #include "i18n.h" #include "util.h" #include "StringBuilder.h" +#include "Function.h" struct DisContext { @@ -126,7 +127,49 @@ read_memory_func (bfd_vma memaddr, bfd_byte *myaddr, unsigned int length, static void print_address_func (bfd_vma addr, disassemble_info *info) { - (*info->fprintf_func) (info->stream, "0x%llx", (unsigned long long) addr); + bfd_signed_vma off; + unsigned long long ta; + Disasm *dis; + switch (info->insn_type) + { + case dis_branch: + case dis_condbranch: + off = (bfd_signed_vma) addr; + dis = (Disasm *) info->stream; + ta = dis->inst_addr + off; + (*info->fprintf_func) (info->stream, ".%c0x%llx [ 0x%llx ]", + off > 0 ? '+' : '-', (long long) (off > 0 ? off : -off), ta); + return; + case dis_jsr: + off = (bfd_signed_vma) addr; + dis = (Disasm *) info->stream; + ta = dis->inst_addr + off; + const char *nm = NULL; + Function *f = dis->map_PC_to_func (ta); + if (f) + { + if (dis->inst_addr >= f->img_offset + && dis->inst_addr < f->img_offset + f->size) + { // Same function + (*info->fprintf_func) (info->stream, ".%c0x%llx [ 0x%llx ]", + off > 0 ? '+' : '-', (long long) (off > 0 ? off : -off), ta); + return; + } + if (f->flags & FUNC_FLAG_PLT) + nm = dis->get_funcname_in_plt(ta); + if (nm == NULL) + nm = f->get_name (); + } + if (nm) + (*info->fprintf_func) (info->stream, "%s [ 0x%llx, .%c0x%llx]", + nm, ta, off > 0 ? '+' : '-', (long long) (off > 0 ? off : -off)); + else + (*info->fprintf_func) (info->stream, + ".%c0x%llx [ 0x%llx ] // Unable to determine target symbol", + off > 0 ? '+' : '-', (long long) (off > 0 ? off : -off), ta); + return; + } + (*info->fprintf_func) (info->stream, "0x%llx", (long long) addr); } static asymbol * @@ -247,35 +290,6 @@ Disasm::remove_disasm_hndl (void *hndl) delete ctx; } -#if 0 -int -Disasm::get_instr_size (uint64_t vaddr, void *hndl) -{ - DisContext *ctx = (DisContext *) hndl; - if (ctx == NULL || vaddr < ctx->first_pc || vaddr >= ctx->last_pc) - return -1; - ctx->pc = vaddr; - size_t sz = ctx->is_Intel ? sizeof (ctx->codeptr) : 4; - if (sz > ctx->last_pc - vaddr) - sz = (size_t) (ctx->last_pc - vaddr); - if (ctx->elf->get_data (ctx->f_offset + (vaddr - ctx->first_pc), - sz, ctx->codeptr) == NULL) - return -1; - - char buf[MAX_DISASM_STR]; - *buf = 0; - uint64_t inst_vaddr = vaddr; -#if MEZ_NEED_TO_FIX - size_t instrs_cnt = 0; - disasm_err_code_t status = disasm (handle, &inst_vaddr, ctx->last_pc, 1, - ctx, buf, sizeof (buf), &instrs_cnt); - if (instrs_cnt != 1 || status != disasm_err_ok) - return -1; -#endif - return (int) (inst_vaddr - vaddr); -} -#endif - void Disasm::set_addr_end (uint64_t end_address) { @@ -312,6 +326,7 @@ Disasm::get_disasm (uint64_t inst_address, uint64_t end_address, printf ("ERROR: unsupported disassemble\n"); return NULL; } + inst_addr = inst_address; inst_size = disassemble (0, &dis_info); if (inst_size <= 0) { @@ -337,83 +352,26 @@ Disasm::get_disasm (uint64_t inst_address, uint64_t end_address, sb.appendf (fmt, bytes); } sb.append (dis_str); -#if MEZ_NEED_TO_FIX - // Write instruction - if (ctx.is_Intel) // longest instruction length for Intel is 7 - sb.appendf (NTXT ("%-7s %s"), parts_array[1], parts_array[2]); - else // longest instruction length for SPARC is 11 - sb.appendf (NTXT ("%-11s %s"), parts_array[1], parts_array[2]); - if (strcmp (parts_array[1], NTXT ("call")) == 0) - { - if (strncmp (parts_array[2], NTXT ("0x"), 2) == 0) - sb.append (GTXT ("\t! (Unable to determine target symbol)")); - } -#endif return sb.toString (); } -#if MEZ_NEED_TO_FIX -void * -Disasm::get_inst_ptr (disasm_handle_t, uint64_t vaddr, void *pass_through) +Function * +Disasm::map_PC_to_func (uint64_t pc) { - // Actually it fetches only one instruction at a time for sparc, - // and one byte at a time for intel. - DisContext *ctx = (DisContext*) pass_through; - size_t sz = ctx->is_Intel ? 1 : 4; - if (vaddr + sz > ctx->last_pc) - { - ctx->codeptr[0] = -1; - return ctx->codeptr; - } - if (ctx->elf->get_data (ctx->f_offset + (vaddr - ctx->first_pc), sz, ctx->codeptr) == NULL) - { - ctx->codeptr[0] = -1; - return ctx->codeptr; - } - if (ctx->elf->need_swap_endian && !ctx->is_Intel) - ctx->codeptr[0] = ctx->elf->decode (ctx->codeptr[0]); - return ctx->codeptr; + uint64_t low_pc = 0; + if (stabs) + return stabs->map_PC_to_func (pc, low_pc, NULL); + return NULL; } -// get a symbol name for an address -disasm_err_code_t -Disasm::get_sym_name (disasm_handle_t, // an open disassembler handle - uint64_t target_address, // the target virtual address - uint64_t inst_address, // virtual address of instruction - // being disassembled - int use_relocation, // flag to use relocation information - char *buffer, // places the symbol here - size_t buffer_size, // limit on symbol length - int *, // sys/elf_{SPARC.386}.h - uint64_t *offset, // from the symbol to the address - void *pass_through) // disassembler context +const char * +Disasm::get_funcname_in_plt (uint64_t pc) { - char buf[MAXPATHLEN]; - if (!use_relocation) - return disasm_err_symbol; - - DisContext *ctxp = (DisContext*) pass_through; - char *name = NULL; - if (ctxp->stabs) - { - uint64_t addr = ctxp->f_offset + (inst_address - ctxp->first_pc); - name = ctxp->stabs->sym_name (target_address, addr, use_relocation); - } - if (name == NULL) - return disasm_err_symbol; - - char *s = NULL; - if (*name == '_') - s = cplus_demangle (name, DMGL_PARAMS); - if (s) + if (stabs) { - snprintf (buffer, buffer_size, NTXT ("%s"), s); - free (s); + Elf *elf = stabs->openElf (true); + if (elf) + return elf->get_funcname_in_plt (pc); } - else - snprintf (buffer, buffer_size, NTXT ("%s"), name); - - *offset = 0; - return disasm_err_ok; + return NULL; } -#endif diff --git a/gprofng/src/Disasm.h b/gprofng/src/Disasm.h index e82b1966b5d..4094c13a20e 100644 --- a/gprofng/src/Disasm.h +++ b/gprofng/src/Disasm.h @@ -48,7 +48,10 @@ public: char *get_disasm (uint64_t inst_address, uint64_t end_address, uint64_t start_address, uint64_t f_offset, int64_t &inst_size); void set_img_name (char *fname); // Only for dynfunc + Function *map_PC_to_func(uint64_t pc); + const char *get_funcname_in_plt (uint64_t pc); + uint64_t inst_addr; // address of current instruction StringBuilder *dis_str; private: diff --git a/gprofng/src/Elf.cc b/gprofng/src/Elf.cc index 469efe75988..9730b996a95 100644 --- a/gprofng/src/Elf.cc +++ b/gprofng/src/Elf.cc @@ -151,6 +151,14 @@ Elf::Elf (char *filename) : DbeMessages (), Data_window (filename) gnu_debug_file = NULL; dbeFile = NULL; abfd = NULL; + bfd_symcnt = -1; + bfd_dynsymcnt = -1; + bfd_synthcnt = -1; + bfd_sym = NULL; + bfd_dynsym = NULL; + bfd_synthsym = NULL; + synthsym = NULL; + if (bfd_status != BFD_INIT_MAGIC) { status = ELF_ERR_CANT_OPEN_FILE; @@ -162,6 +170,7 @@ Elf::Elf (char *filename) : DbeMessages (), Data_window (filename) status = ELF_ERR_CANT_OPEN_FILE; return; } + abfd->flags |= BFD_DECOMPRESS; if (!bfd_check_format (abfd, bfd_object)) { bfd_close (abfd); @@ -270,6 +279,10 @@ Elf::~Elf () delete elfSymbols; delete gnu_debug_file; delete dbeFile; + delete synthsym; + free (bfd_sym); + free (bfd_dynsym); + free (bfd_synthsym); if (abfd) bfd_close (abfd); } @@ -722,6 +735,87 @@ Elf::find_ancillary_files (char *lo_name) return NULL; } +void +Elf::get_bfd_symbols() +{ + if (bfd_symcnt < 0) + { + if ((bfd_get_file_flags (abfd) & HAS_SYMS) != 0) + bfd_symcnt = bfd_get_symtab_upper_bound (abfd); + if (bfd_symcnt > 0) + { + bfd_sym = (asymbol **) malloc (bfd_symcnt); + bfd_symcnt = bfd_canonicalize_symtab (abfd, bfd_sym); + if (bfd_symcnt < 0) + { + free (bfd_sym); + bfd_sym = NULL; + } + } + else + bfd_symcnt = 0; + } + + if (bfd_dynsymcnt < 0) + { + bfd_dynsymcnt = bfd_get_dynamic_symtab_upper_bound (abfd); + if (bfd_dynsymcnt > 0) + { + bfd_dynsym = (asymbol **) malloc (bfd_dynsymcnt); + bfd_dynsymcnt = bfd_canonicalize_dynamic_symtab (abfd, bfd_dynsym); + if (bfd_dynsymcnt < 0) + { + free (bfd_dynsym); + bfd_dynsym = NULL; + } + } + else + bfd_dynsymcnt = 0; + } + if (bfd_synthcnt < 0) + { + bfd_synthcnt = bfd_get_synthetic_symtab (abfd, bfd_symcnt, bfd_sym, + bfd_dynsymcnt, bfd_dynsym, &bfd_synthsym); + if (bfd_synthcnt < 0) + bfd_synthcnt = 0; + } +} + +static int +cmp_sym_addr (const void *a, const void *b) +{ + asymbol *sym1 = *((asymbol **) a); + asymbol *sym2 = *((asymbol **) b); + uint64_t a1 = sym1->value; + uint64_t a2 = sym2->value; + if (sym1->section) + a1 += sym1->section->vma; + if (sym2->section) + a2 += sym2->section->vma; + return a1 < a2 ? -1 : (a1 == a2 ? 0 : 1); +} + +const char * +Elf::get_funcname_in_plt (uint64_t pc) +{ + if (synthsym == NULL) + { + get_bfd_symbols(); + synthsym = new Vector (bfd_synthcnt + 1); + for (long i = 0; i < bfd_synthcnt; i++) + synthsym->append (bfd_synthsym + i); + synthsym->sort (cmp_sym_addr); + } + + asymbol sym, *symp = &sym; + sym.section = NULL; + sym.value = pc; + long ind = synthsym->bisearch (0, -1, &symp, cmp_sym_addr); + if (ind >= 0) + return synthsym->get (ind)->name; + return NULL; +} + char* Elf::get_location () { diff --git a/gprofng/src/Elf.h b/gprofng/src/Elf.h index 85059bc613c..e5a4f68db69 100644 --- a/gprofng/src/Elf.h +++ b/gprofng/src/Elf.h @@ -96,6 +96,7 @@ public: Elf_Internal_Rela *elf_getrela (Elf_Data *edta, unsigned int ndx, Elf_Internal_Rela *dst); Elf64_Ancillary *elf_getancillary (Elf_Data *edta, unsigned int ndx, Elf64_Ancillary *dst); Elf *find_ancillary_files (char *lo_name); // read the .gnu_debuglink and .SUNW_ancillary seections + const char *get_funcname_in_plt (uint64_t pc); char *get_location (); char *dump (); void dump_elf_sec (); @@ -135,12 +136,20 @@ public: protected: Elf *get_related_file (const char *lo_name, const char *nm); + void get_bfd_symbols(); int elf_class; int elf_datatype; Elf_Internal_Ehdr *ehdrp; Elf_Data **data; bfd *abfd; static int bfd_status; + long bfd_symcnt; + long bfd_dynsymcnt; + long bfd_synthcnt; + asymbol **bfd_sym; + asymbol **bfd_dynsym; + asymbol *bfd_synthsym; + Vector *synthsym; }; diff --git a/gprofng/src/Stabs.cc b/gprofng/src/Stabs.cc index ac2ff48f7e8..82d85efabeb 100644 --- a/gprofng/src/Stabs.cc +++ b/gprofng/src/Stabs.cc @@ -305,7 +305,6 @@ Stabs::Stabs (char *_path, char *_lo_name) Stabs::~Stabs () { - delete pltSym; delete SymLstByName; Destroy (SymLst); Destroy (RelLst); @@ -1618,9 +1617,9 @@ Stabs::createFunction (LoadObject *lo, Module *module, Symbol *sym) Function *func = dbeSession->createFunction (); func->module = module; func->img_fname = path; - func->img_offset = (off_t) sym->img_offset; + func->img_offset = sym->img_offset; func->save_addr = sym->save; - func->size = (uint32_t) sym->size; + func->size = sym->size; func->set_name (sym->name); func->elfSym = sym; module->functions->append (func); @@ -1691,12 +1690,12 @@ Stabs::check_Symtab () Elf *elf = openElf (true); if (elf == NULL) return; - if (elfDis->plt != 0) + if (elf->plt != 0) { - Elf_Internal_Shdr *shdr = elfDis->get_shdr (elfDis->plt); + Elf_Internal_Shdr *shdr = elf->get_shdr (elf->plt); if (shdr) { - pltSym = new Symbol (); + pltSym = new Symbol (SymLst); pltSym->value = shdr->sh_addr; pltSym->size = shdr->sh_size; pltSym->img_offset = shdr->sh_offset; @@ -1744,7 +1743,8 @@ Stabs::readSymSec (unsigned int sec, Elf *elf) switch (GELF_ST_TYPE (Sym.st_info)) { case STT_FUNC: - // Skip UNDEF symbols (bug 4817083) + if (Sym.st_size == 0) + break; if (Sym.st_shndx == 0) { if (Sym.st_value == 0) @@ -1752,8 +1752,8 @@ Stabs::readSymSec (unsigned int sec, Elf *elf) sitem = new Symbol (SymLst); sitem->flags |= SYM_UNDEF; if (pltSym) - sitem->img_offset = (uint32_t) (pltSym->img_offset + - Sym.st_value - pltSym->value); + sitem->img_offset = pltSym->img_offset + + Sym.st_value - pltSym->value; } else { @@ -1761,8 +1761,8 @@ Stabs::readSymSec (unsigned int sec, Elf *elf) if (shdrp == NULL) break; sitem = new Symbol (SymLst); - sitem->img_offset = (uint32_t) (shdrp->sh_offset + - Sym.st_value - shdrp->sh_addr); + sitem->img_offset = shdrp->sh_offset + + Sym.st_value - shdrp->sh_addr; } sitem->size = Sym.st_size; sitem->name = dbe_strdup (st_name); @@ -1882,7 +1882,7 @@ Stabs::check_Relocs () if (shdr_txt == NULL) continue; if (!(shdr_txt->sh_flags & SHF_EXECINSTR)) - continue; + continue; // Get corresponding symbol table section Elf_Internal_Shdr *shdr_sym = elf->get_shdr (shdr->sh_link); @@ -2305,9 +2305,9 @@ Stabs::append_local_funcs (Module *module, int first_ind) Function *func = dbeSession->createFunction (); sitem->func = func; func->img_fname = path; - func->img_offset = (off_t) sitem->img_offset; - func->save_addr = (uint32_t) sitem->save; - func->size = (uint32_t) sitem->size; + func->img_offset = sitem->img_offset; + func->save_addr = sitem->save; + func->size = sitem->size; func->module = module; func->set_name (sitem->name); module->functions->append (func); @@ -2381,9 +2381,9 @@ Stabs::append_Function (Module *module, char *fname) return sitem->func; sitem->func = func = dbeSession->createFunction (); func->img_fname = path; - func->img_offset = (off_t) sitem->img_offset; - func->save_addr = (uint32_t) sitem->save; - func->size = (uint32_t) sitem->size; + func->img_offset = sitem->img_offset; + func->save_addr = sitem->save; + func->size = sitem->size; } else func = dbeSession->createFunction (); @@ -2436,9 +2436,9 @@ Stabs::append_Function (Module *module, char *linkerName, uint64_t pc) sitem->func = func = dbeSession->createFunction (); func->img_fname = path; - func->img_offset = (off_t) sitem->img_offset; - func->save_addr = (uint32_t) sitem->save; - func->size = (uint32_t) sitem->size; + func->img_offset = sitem->img_offset; + func->save_addr = sitem->save; + func->size = sitem->size; func->module = module; func->set_name (sitem->name); //XXXX ?? Now call it to set obj->name module->functions->append (func);