Index: llvm/docs/CommandGuide/llvm-dwarfdump.rst =================================================================== --- llvm/docs/CommandGuide/llvm-dwarfdump.rst +++ llvm/docs/CommandGuide/llvm-dwarfdump.rst @@ -105,6 +105,10 @@ When displaying debug info entries, only show children to a maximum depth of . +.. option:: --show-section-sizes + + Show the sizes of all debug sections. + .. option:: --statistics Collect debug info quality metrics and print the results Index: llvm/test/tools/llvm-dwarfdump/X86/section_sizes.test =================================================================== --- /dev/null +++ llvm/test/tools/llvm-dwarfdump/X86/section_sizes.test @@ -0,0 +1,42 @@ +## Check how llvm-dwarfdump calculates section sizes with --show-section-sizes. + +# RUN: yaml2obj --docnum=1 %s -o %t +# RUN: llvm-dwarfdump --show-section-sizes %t | FileCheck %s --match-full-lines --strict-whitespace + +# CHECK:file: {{.*}} +# CHECK-NEXT:---------------------------------------------------- +# CHECK-NEXT: SECTION SIZE +# CHECK-NEXT:------------ ----------------------- +# CHECK-NEXT: .debug_foo 100 (12.38%) +# CHECK-NEXT: .debug_info 17 (2.10%) +# CHECK-NEXT: .debug_line 19 (2.35%) +# CHECK-NEXT: .debug_loc 1 (0.12%) +# CHECK-NEXT: .debug_str 13 (1.61%) +# CHECK-EMPTY: +# CHECK-NEXT: total debug: 150 (18.56%) +# CHECK-NEXT:---------------------------------------------------- +# CHECK-NEXT: TOTAL FILE SIZE: 808 +# CHECK-NEXT:---------------------------------------------------- + +--- !ELF +FileHeader: + Class: ELFCLASS64 + Data: ELFDATA2LSB + Type: ET_REL + Machine: EM_X86_64 +Sections: + - Name: .debug_info + Type: SHT_PROGBITS + Size: 17 + - Name: .debug_line + Type: SHT_PROGBITS + Size: 19 + - Name: .debug_loc + Type: SHT_PROGBITS + Size: 1 + - Name: .debug_str + Type: SHT_PROGBITS + Size: 13 + - Name: .debug_foo + Type: SHT_PROGBITS + Size: 100 Index: llvm/tools/llvm-dwarfdump/CMakeLists.txt =================================================================== --- llvm/tools/llvm-dwarfdump/CMakeLists.txt +++ llvm/tools/llvm-dwarfdump/CMakeLists.txt @@ -9,6 +9,7 @@ add_llvm_tool(llvm-dwarfdump Statistics.cpp + SectionSizes.cpp llvm-dwarfdump.cpp ) Index: llvm/tools/llvm-dwarfdump/SectionSizes.cpp =================================================================== --- /dev/null +++ llvm/tools/llvm-dwarfdump/SectionSizes.cpp @@ -0,0 +1,105 @@ +//===-- SectionSizes.cpp - Debug section sizes ----------------------------===// +// +// 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 +// +//===----------------------------------------------------------------------===// + +#include "llvm/DebugInfo/DIContext.h" +#include "llvm/DebugInfo/DWARF/DWARFContext.h" +#include "llvm/Object/ObjectFile.h" +#include "llvm/Support/WithColor.h" + +#include + +#define DEBUG_TYPE "dwarfdump" +using namespace llvm; +using namespace object; + +using SectionSizeMap = std::map; + +/// Holds cumulative section sizes for an object file. +struct SectionSizes { + /// Map of .debug section names and their sizes across all such-named + /// sections. + SectionSizeMap DebugSectionSizes; + /// Total number of bytes of all sections. + uint64_t TotalObjectSize = 0; + /// Total number of bytes of all debug sections. + uint64_t TotalDebugSectionsSize = 0; +}; + +static void prettyPrintSectionSizes(const ObjectFile &Obj, + const SectionSizes &Sizes, + raw_ostream &OS) { + OS << "----------------------------------------------------" + << "\n"; + OS << " SECTION SIZE\n"; + OS << "------------ -----------------------\n"; + + for (const auto &DebugSec : Sizes.DebugSectionSizes) { + OS << " " << left_justify(DebugSec.first, 14) << " " + << format_decimal(DebugSec.second, 8) << " (" + << format("%0.2f", DebugSec.second / (double)Sizes.TotalObjectSize * 100) + << "%)\n"; + } + OS << "\n"; + OS << " total debug: " << Sizes.TotalDebugSectionsSize << " (" + << format("%0.2f", Sizes.TotalDebugSectionsSize / + (double)Sizes.TotalObjectSize * 100) + << "%)\n"; + OS << "----------------------------------------------------" + << "\n"; + OS << " TOTAL FILE SIZE: " << Sizes.TotalObjectSize << "\n"; + OS << "----------------------------------------------------" + << "\n"; +} + +static bool isDebugSection(StringRef SectionName) { + return SectionName.startswith(".debug") || + SectionName.startswith(".zdebug") || SectionName == ".gdb_index"; +} + +static void calculateSizes(const ObjectFile &Obj, SectionSizes &Sizes, + const Twine &Filename) { + // Get total size. + Sizes.TotalObjectSize = Obj.getData().size(); + + for (const SectionRef &Section : Obj.sections()) { + StringRef SectionName; + if (Expected NameOrErr = Section.getName()) { + SectionName = *NameOrErr; + } else { + WithColor::defaultWarningHandler( + createFileError(Filename, NameOrErr.takeError())); + } + + LLVM_DEBUG(dbgs() << SectionName.str() << ": " << Section.getSize()); + + if (!isDebugSection(SectionName)) + continue; + + Sizes.TotalDebugSectionsSize += Section.getSize(); + Sizes.DebugSectionSizes[SectionName] += Section.getSize(); + } +} + +bool collectObjectSectionSizes(ObjectFile &Obj, DWARFContext &DICtx, + Twine Filename, raw_ostream &OS) { + // Unused, but we want to keep using the llvm-dwarfdump function handler + // interface. + (void)DICtx; + + SectionSizes Sizes; + + // Get the section sizes. + calculateSizes(Obj, Sizes, Filename); + + OS << "----------------------------------------------------\n"; + OS << "file: " << Filename.str() << "\n"; + + prettyPrintSectionSizes(Obj, Sizes, OS); + + return true; +} Index: llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp =================================================================== --- llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp +++ llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp @@ -208,6 +208,10 @@ Statistics("statistics", cl::desc("Emit JSON-formatted debug info quality metrics."), cat(DwarfDumpCategory)); +static cl::opt + ShowSectionSizes("show-section-sizes", + cl::desc("Show the sizes of all debug sections."), + cat(DwarfDumpCategory)); static opt Verify("verify", desc("Verify the DWARF debug info."), cat(DwarfDumpCategory)); static opt Quiet("quiet", desc("Use with -verify to not emit to STDOUT."), @@ -413,6 +417,9 @@ bool collectStatsForObjectFile(ObjectFile &Obj, DWARFContext &DICtx, Twine Filename, raw_ostream &OS); +bool collectObjectSectionSizes(ObjectFile &Obj, DWARFContext &DICtx, + Twine Filename, raw_ostream &OS); + static bool dumpObjectFile(ObjectFile &Obj, DWARFContext &DICtx, Twine Filename, raw_ostream &OS) { logAllUnhandledErrors(DICtx.loadRegisterInfo(Obj), errs(), @@ -635,12 +642,16 @@ return handleFile(Object, verifyObjectFile, OutputFile.os()); })) return 1; - } else if (Statistics) + } else if (Statistics) { for (auto Object : Objects) handleFile(Object, collectStatsForObjectFile, OutputFile.os()); - else + } else if (ShowSectionSizes) { + for (auto Object : Objects) + handleFile(Object, collectObjectSectionSizes, OutputFile.os()); + } else { for (auto Object : Objects) handleFile(Object, dumpObjectFile, OutputFile.os()); + } return EXIT_SUCCESS; }