337 lines · cpp
1//===- MapFile.cpp --------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements the /map option in the same format as link.exe10// (based on observations)11//12// Header (program name, timestamp info, preferred load address)13//14// Section list (Start = Section index:Base address):15// Start Length Name Class16// 0001:00001000 00000015H .text CODE17//18// Symbols list:19// Address Publics by Value Rva + Base Lib:Object20// 0001:00001000 main 0000000140001000 main.obj21// 0001:00001300 ?__scrt_common_main@@YAHXZ 0000000140001300 libcmt:exe_main.obj22//23// entry point at 0001:0000036024//25// Static symbols26//27// 0000:00000000 __guard_fids__ 0000000140000000 libcmt : exe_main.obj28//===----------------------------------------------------------------------===//29 30#include "MapFile.h"31#include "COFFLinkerContext.h"32#include "SymbolTable.h"33#include "Symbols.h"34#include "Writer.h"35#include "lld/Common/Timer.h"36#include "llvm/Support/Parallel.h"37#include "llvm/Support/Path.h"38#include "llvm/Support/TimeProfiler.h"39#include "llvm/Support/raw_ostream.h"40 41using namespace llvm;42using namespace llvm::object;43using namespace lld;44using namespace lld::coff;45 46// Print out the first two columns of a line.47static void writeHeader(raw_ostream &os, uint32_t sec, uint64_t addr) {48 os << format(" %04x:%08llx", sec, addr);49}50 51// Write the time stamp with the format used by link.exe52// It seems identical to strftime with "%c" on msvc build, but we need a53// locale-agnostic version.54static void writeFormattedTimestamp(raw_ostream &os, time_t tds) {55 constexpr const char *const days[7] = {"Sun", "Mon", "Tue", "Wed",56 "Thu", "Fri", "Sat"};57 constexpr const char *const months[12] = {"Jan", "Feb", "Mar", "Apr",58 "May", "Jun", "Jul", "Aug",59 "Sep", "Oct", "Nov", "Dec"};60 tm *time = localtime(&tds);61 os << format("%s %s %2d %02d:%02d:%02d %d", days[time->tm_wday],62 months[time->tm_mon], time->tm_mday, time->tm_hour, time->tm_min,63 time->tm_sec, time->tm_year + 1900);64}65 66static void sortUniqueSymbols(std::vector<Defined *> &syms,67 uint64_t imageBase) {68 // Build helper vector69 using SortEntry = std::pair<Defined *, size_t>;70 std::vector<SortEntry> v;71 v.resize(syms.size());72 for (size_t i = 0, e = syms.size(); i < e; ++i)73 v[i] = SortEntry(syms[i], i);74 75 // Remove duplicate symbol pointers76 parallelSort(v, std::less<SortEntry>());77 auto end = llvm::unique(v, [](const SortEntry &a, const SortEntry &b) {78 return a.first == b.first;79 });80 v.erase(end, v.end());81 82 // Sort by RVA then original order83 parallelSort(v, [imageBase](const SortEntry &a, const SortEntry &b) {84 // Add config.imageBase to avoid comparing "negative" RVAs.85 // This can happen with symbols of Absolute kind86 uint64_t rvaa = imageBase + a.first->getRVA();87 uint64_t rvab = imageBase + b.first->getRVA();88 return rvaa < rvab || (rvaa == rvab && a.second < b.second);89 });90 91 syms.resize(v.size());92 for (size_t i = 0, e = v.size(); i < e; ++i)93 syms[i] = v[i].first;94}95 96// Returns the lists of all symbols that we want to print out.97static void getSymbols(const COFFLinkerContext &ctx,98 std::vector<Defined *> &syms,99 std::vector<Defined *> &staticSyms) {100 101 for (ObjFile *file : ctx.objFileInstances)102 for (Symbol *b : file->getSymbols()) {103 if (!b || !b->isLive())104 continue;105 if (auto *sym = dyn_cast<DefinedCOFF>(b)) {106 COFFSymbolRef symRef = sym->getCOFFSymbol();107 if (!symRef.isSectionDefinition() &&108 symRef.getStorageClass() != COFF::IMAGE_SYM_CLASS_LABEL) {109 if (symRef.getStorageClass() == COFF::IMAGE_SYM_CLASS_STATIC)110 staticSyms.push_back(sym);111 else112 syms.push_back(sym);113 }114 } else if (auto *sym = dyn_cast<Defined>(b)) {115 syms.push_back(sym);116 }117 }118 119 for (ImportFile *file : ctx.importFileInstances) {120 if (!file->live)121 continue;122 123 if (file->impSym)124 syms.push_back(file->impSym);125 if (file->thunkSym && file->thunkSym->isLive())126 syms.push_back(file->thunkSym);127 if (file->auxThunkSym && file->auxThunkSym->isLive())128 syms.push_back(file->auxThunkSym);129 if (file->impchkThunk)130 syms.push_back(file->impchkThunk->sym);131 if (file->impECSym)132 syms.push_back(file->impECSym);133 if (file->auxImpCopySym)134 syms.push_back(file->auxImpCopySym);135 }136 137 sortUniqueSymbols(syms, ctx.config.imageBase);138 sortUniqueSymbols(staticSyms, ctx.config.imageBase);139}140 141// Construct a map from symbols to their stringified representations.142static DenseMap<Defined *, std::string>143getSymbolStrings(const COFFLinkerContext &ctx, ArrayRef<Defined *> syms) {144 std::vector<std::string> str(syms.size());145 parallelFor((size_t)0, syms.size(), [&](size_t i) {146 raw_string_ostream os(str[i]);147 Defined *sym = syms[i];148 149 uint16_t sectionIdx = 0;150 uint64_t address = 0;151 SmallString<128> fileDescr;152 153 if (auto *absSym = dyn_cast<DefinedAbsolute>(sym)) {154 address = absSym->getVA();155 fileDescr = "<absolute>";156 } else if (isa<DefinedSynthetic>(sym)) {157 fileDescr = "<linker-defined>";158 } else if (isa<DefinedCommon>(sym)) {159 fileDescr = "<common>";160 } else if (Chunk *chunk = sym->getChunk()) {161 address = sym->getRVA();162 if (OutputSection *sec = ctx.getOutputSection(chunk))163 address -= sec->header.VirtualAddress;164 165 sectionIdx = chunk->getOutputSectionIdx();166 167 InputFile *file;168 if (auto *impSym = dyn_cast<DefinedImportData>(sym))169 file = impSym->file;170 else if (auto *thunkSym = dyn_cast<DefinedImportThunk>(sym))171 file = thunkSym->wrappedSym->file;172 else173 file = sym->getFile();174 175 if (file) {176 if (!file->parentName.empty()) {177 fileDescr = sys::path::filename(file->parentName);178 sys::path::replace_extension(fileDescr, "");179 fileDescr += ":";180 }181 fileDescr += sys::path::filename(file->getName());182 }183 }184 writeHeader(os, sectionIdx, address);185 os << " ";186 os << left_justify(sym->getName(), 26);187 os << " ";188 os << format_hex_no_prefix((ctx.config.imageBase + sym->getRVA()), 16);189 if (!fileDescr.empty()) {190 os << " "; // FIXME : Handle "f" and "i" flags sometimes generated191 // by link.exe in those spaces192 os << fileDescr;193 }194 });195 196 DenseMap<Defined *, std::string> ret;197 for (size_t i = 0, e = syms.size(); i < e; ++i)198 ret[syms[i]] = std::move(str[i]);199 return ret;200}201 202void lld::coff::writeMapFile(COFFLinkerContext &ctx) {203 if (ctx.config.mapFile.empty())204 return;205 206 llvm::TimeTraceScope timeScope("Map file");207 std::error_code ec;208 raw_fd_ostream os(ctx.config.mapFile, ec, sys::fs::OF_None);209 if (ec)210 Fatal(ctx) << "cannot open " << ctx.config.mapFile << ": " << ec.message();211 212 ScopedTimer t1(ctx.totalMapTimer);213 214 // Collect symbol info that we want to print out.215 ScopedTimer t2(ctx.symbolGatherTimer);216 std::vector<Defined *> syms;217 std::vector<Defined *> staticSyms;218 getSymbols(ctx, syms, staticSyms);219 t2.stop();220 221 ScopedTimer t3(ctx.symbolStringsTimer);222 DenseMap<Defined *, std::string> symStr = getSymbolStrings(ctx, syms);223 DenseMap<Defined *, std::string> staticSymStr =224 getSymbolStrings(ctx, staticSyms);225 t3.stop();226 227 ScopedTimer t4(ctx.writeTimer);228 SmallString<128> AppName = sys::path::filename(ctx.config.outputFile);229 sys::path::replace_extension(AppName, "");230 231 // Print out the file header232 os << " " << AppName << "\n";233 os << "\n";234 235 os << " Timestamp is " << format_hex_no_prefix(ctx.config.timestamp, 8)236 << " (";237 if (ctx.config.repro) {238 os << "Repro mode";239 } else {240 writeFormattedTimestamp(os, ctx.config.timestamp);241 }242 os << ")\n";243 244 os << "\n";245 os << " Preferred load address is "246 << format_hex_no_prefix(ctx.config.imageBase, 16) << "\n";247 os << "\n";248 249 // Print out section table.250 os << " Start Length Name Class\n";251 252 for (OutputSection *sec : ctx.outputSections) {253 // Merge display of chunks with same sectionName254 std::vector<std::pair<SectionChunk *, SectionChunk *>> ChunkRanges;255 for (Chunk *c : sec->chunks) {256 auto *sc = dyn_cast<SectionChunk>(c);257 if (!sc)258 continue;259 260 if (ChunkRanges.empty() ||261 c->getSectionName() != ChunkRanges.back().first->getSectionName()) {262 ChunkRanges.emplace_back(sc, sc);263 } else {264 ChunkRanges.back().second = sc;265 }266 }267 268 const bool isCodeSection =269 (sec->header.Characteristics & COFF::IMAGE_SCN_CNT_CODE) &&270 (sec->header.Characteristics & COFF::IMAGE_SCN_MEM_READ) &&271 (sec->header.Characteristics & COFF::IMAGE_SCN_MEM_EXECUTE);272 StringRef SectionClass = (isCodeSection ? "CODE" : "DATA");273 274 for (auto &cr : ChunkRanges) {275 size_t size =276 cr.second->getRVA() + cr.second->getSize() - cr.first->getRVA();277 278 auto address = cr.first->getRVA() - sec->header.VirtualAddress;279 writeHeader(os, sec->sectionIndex, address);280 os << " " << format_hex_no_prefix(size, 8) << "H";281 os << " " << left_justify(cr.first->getSectionName(), 23);282 os << " " << SectionClass;283 os << '\n';284 }285 }286 287 // Print out the symbols table (without static symbols)288 os << "\n";289 os << " Address Publics by Value Rva+Base"290 " Lib:Object\n";291 os << "\n";292 for (Defined *sym : syms)293 os << symStr[sym] << '\n';294 295 // Print out the entry point.296 os << "\n";297 298 uint16_t entrySecIndex = 0;299 uint64_t entryAddress = 0;300 301 if (!ctx.config.noEntry) {302 Defined *entry = dyn_cast_or_null<Defined>(ctx.symtab.entry);303 if (entry) {304 Chunk *chunk = entry->getChunk();305 entrySecIndex = chunk->getOutputSectionIdx();306 entryAddress =307 entry->getRVA() - ctx.getOutputSection(chunk)->header.VirtualAddress;308 }309 }310 os << " entry point at ";311 os << format("%04x:%08llx", entrySecIndex, entryAddress);312 os << "\n";313 314 // Print out the static symbols315 os << "\n";316 os << " Static symbols\n";317 os << "\n";318 for (Defined *sym : staticSyms)319 os << staticSymStr[sym] << '\n';320 321 // Print out the exported functions322 if (ctx.config.mapInfo) {323 os << "\n";324 os << " Exports\n";325 os << "\n";326 os << " ordinal name\n\n";327 for (Export &e : ctx.symtab.exports) {328 os << format(" %7d", e.ordinal) << " " << e.name << "\n";329 if (!e.extName.empty() && e.extName != e.name)330 os << " exported name: " << e.extName << "\n";331 }332 }333 334 t4.stop();335 t1.stop();336}337