vendor/llvm/llvm-trunk-r366426

1 files changed, 138 insertions, 20 deletions

diff --git a/tools/llvm-objcopy/COFF/COFFObjcopy.cpp b/tools/llvm-objcopy/COFF/COFFObjcopy.cpp
index 6b386d29979c..4ae46851a66f 100644
--- a/tools/llvm-objcopy/COFF/COFFObjcopy.cpp
+++ b/tools/llvm-objcopy/COFF/COFFObjcopy.cpp
@@ -1,9 +1,8 @@
 //===- COFFObjcopy.cpp ----------------------------------------------------===//
 //
-//                      The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 
@@ -18,6 +17,8 @@
 #include "llvm/Object/Binary.h"
 #include "llvm/Object/COFF.h"
 #include "llvm/Support/Errc.h"
+#include "llvm/Support/JamCRC.h"
+#include "llvm/Support/Path.h"
 #include <cassert>
 
 namespace llvm {
@@ -27,14 +28,104 @@ namespace coff {
 using namespace object;
 using namespace COFF;
 
+static bool isDebugSection(const Section &Sec) {
+  return Sec.Name.startswith(".debug");
+}
+
+static uint64_t getNextRVA(const Object &Obj) {
+  if (Obj.getSections().empty())
+    return 0;
+  const Section &Last = Obj.getSections().back();
+  return alignTo(Last.Header.VirtualAddress + Last.Header.VirtualSize,
+                 Obj.IsPE ? Obj.PeHeader.SectionAlignment : 1);
+}
+
+static uint32_t getCRC32(StringRef Data) {
+  JamCRC CRC;
+  CRC.update(ArrayRef<char>(Data.data(), Data.size()));
+  // The CRC32 value needs to be complemented because the JamCRC dosn't
+  // finalize the CRC32 value. It also dosn't negate the initial CRC32 value
+  // but it starts by default at 0xFFFFFFFF which is the complement of zero.
+  return ~CRC.getCRC();
+}
+
+static std::vector<uint8_t> createGnuDebugLinkSectionContents(StringRef File) {
+  ErrorOr<std::unique_ptr<MemoryBuffer>> LinkTargetOrErr =
+      MemoryBuffer::getFile(File);
+  if (!LinkTargetOrErr)
+    error("'" + File + "': " + LinkTargetOrErr.getError().message());
+  auto LinkTarget = std::move(*LinkTargetOrErr);
+  uint32_t CRC32 = getCRC32(LinkTarget->getBuffer());
+
+  StringRef FileName = sys::path::filename(File);
+  size_t CRCPos = alignTo(FileName.size() + 1, 4);
+  std::vector<uint8_t> Data(CRCPos + 4);
+  memcpy(Data.data(), FileName.data(), FileName.size());
+  support::endian::write32le(Data.data() + CRCPos, CRC32);
+  return Data;
+}
+
+static void addGnuDebugLink(Object &Obj, StringRef DebugLinkFile) {
+  uint32_t StartRVA = getNextRVA(Obj);
+
+  std::vector<Section> Sections;
+  Section Sec;
+  Sec.setOwnedContents(createGnuDebugLinkSectionContents(DebugLinkFile));
+  Sec.Name = ".gnu_debuglink";
+  Sec.Header.VirtualSize = Sec.getContents().size();
+  Sec.Header.VirtualAddress = StartRVA;
+  Sec.Header.SizeOfRawData = alignTo(Sec.Header.VirtualSize,
+                                     Obj.IsPE ? Obj.PeHeader.FileAlignment : 1);
+  // Sec.Header.PointerToRawData is filled in by the writer.
+  Sec.Header.PointerToRelocations = 0;
+  Sec.Header.PointerToLinenumbers = 0;
+  // Sec.Header.NumberOfRelocations is filled in by the writer.
+  Sec.Header.NumberOfLinenumbers = 0;
+  Sec.Header.Characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA |
+                               IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_DISCARDABLE;
+  Sections.push_back(Sec);
+  Obj.addSections(Sections);
+}
+
 static Error handleArgs(const CopyConfig &Config, Object &Obj) {
+  // Perform the actual section removals.
+  Obj.removeSections([&Config](const Section &Sec) {
+    // Contrary to --only-keep-debug, --only-section fully removes sections that
+    // aren't mentioned.
+    if (!Config.OnlySection.empty() &&
+        !is_contained(Config.OnlySection, Sec.Name))
+      return true;
+
+    if (Config.StripDebug || Config.StripAll || Config.StripAllGNU ||
+        Config.DiscardMode == DiscardType::All || Config.StripUnneeded) {
+      if (isDebugSection(Sec) &&
+          (Sec.Header.Characteristics & IMAGE_SCN_MEM_DISCARDABLE) != 0)
+        return true;
+    }
+
+    if (is_contained(Config.ToRemove, Sec.Name))
+      return true;
+
+    return false;
+  });
+
+  if (Config.OnlyKeepDebug) {
+    // For --only-keep-debug, we keep all other sections, but remove their
+    // content. The VirtualSize field in the section header is kept intact.
+    Obj.truncateSections([](const Section &Sec) {
+      return !isDebugSection(Sec) && Sec.Name != ".buildid" &&
+             ((Sec.Header.Characteristics &
+               (IMAGE_SCN_CNT_CODE | IMAGE_SCN_CNT_INITIALIZED_DATA)) != 0);
+    });
+  }
+
   // StripAll removes all symbols and thus also removes all relocations.
   if (Config.StripAll || Config.StripAllGNU)
-    for (Section &Sec : Obj.Sections)
+    for (Section &Sec : Obj.getMutableSections())
       Sec.Relocs.clear();
 
   // If we need to do per-symbol removals, initialize the Referenced field.
-  if (Config.StripUnneeded || Config.DiscardAll ||
+  if (Config.StripUnneeded || Config.DiscardMode == DiscardType::All ||
       !Config.SymbolsToRemove.empty())
     if (Error E = Obj.markSymbols())
       return E;
@@ -50,47 +141,74 @@ static Error handleArgs(const CopyConfig &Config, Object &Obj) {
       // Explicitly removing a referenced symbol is an error.
       if (Sym.Referenced)
         reportError(Config.OutputFilename,
-                    make_error<StringError>(
-                        "not stripping symbol '" + Sym.Name +
-                            "' because it is named in a relocation.",
-                        llvm::errc::invalid_argument));
+                    createStringError(llvm::errc::invalid_argument,
+                                      "not stripping symbol '%s' because it is "
+                                      "named in a relocation",
+                                      Sym.Name.str().c_str()));
       return true;
     }
 
     if (!Sym.Referenced) {
       // With --strip-unneeded, GNU objcopy removes all unreferenced local
       // symbols, and any unreferenced undefined external.
-      if (Config.StripUnneeded &&
-          (Sym.Sym.StorageClass == IMAGE_SYM_CLASS_STATIC ||
-           Sym.Sym.SectionNumber == 0))
-        return true;
+      // With --strip-unneeded-symbol we strip only specific unreferenced
+      // local symbol instead of removing all of such.
+      if (Sym.Sym.StorageClass == IMAGE_SYM_CLASS_STATIC ||
+          Sym.Sym.SectionNumber == 0)
+        if (Config.StripUnneeded ||
+            is_contained(Config.UnneededSymbolsToRemove, Sym.Name))
+          return true;
 
       // GNU objcopy keeps referenced local symbols and external symbols
       // if --discard-all is set, similar to what --strip-unneeded does,
       // but undefined local symbols are kept when --discard-all is set.
-      if (Config.DiscardAll && Sym.Sym.StorageClass == IMAGE_SYM_CLASS_STATIC &&
+      if (Config.DiscardMode == DiscardType::All &&
+          Sym.Sym.StorageClass == IMAGE_SYM_CLASS_STATIC &&
           Sym.Sym.SectionNumber != 0)
         return true;
     }
 
     return false;
   });
+
+  if (!Config.AddGnuDebugLink.empty())
+    addGnuDebugLink(Obj, Config.AddGnuDebugLink);
+
+  if (Config.AllowBrokenLinks || !Config.BuildIdLinkDir.empty() ||
+      Config.BuildIdLinkInput || Config.BuildIdLinkOutput ||
+      !Config.SplitDWO.empty() || !Config.SymbolsPrefix.empty() ||
+      !Config.AllocSectionsPrefix.empty() || !Config.AddSection.empty() ||
+      !Config.DumpSection.empty() || !Config.KeepSection.empty() ||
+      !Config.SymbolsToGlobalize.empty() || !Config.SymbolsToKeep.empty() ||
+      !Config.SymbolsToLocalize.empty() || !Config.SymbolsToWeaken.empty() ||
+      !Config.SymbolsToKeepGlobal.empty() || !Config.SectionsToRename.empty() ||
+      !Config.SetSectionFlags.empty() || !Config.SymbolsToRename.empty() ||
+      Config.ExtractDWO || Config.KeepFileSymbols || Config.LocalizeHidden ||
+      Config.PreserveDates || Config.StripDWO || Config.StripNonAlloc ||
+      Config.StripSections || Config.Weaken || Config.DecompressDebugSections ||
+      Config.DiscardMode == DiscardType::Locals ||
+      !Config.SymbolsToAdd.empty() || Config.EntryExpr) {
+    return createStringError(llvm::errc::invalid_argument,
+                             "option not supported by llvm-objcopy for COFF");
+  }
+
   return Error::success();
 }
 
-void executeObjcopyOnBinary(const CopyConfig &Config,
-                            object::COFFObjectFile &In, Buffer &Out) {
+Error executeObjcopyOnBinary(const CopyConfig &Config, COFFObjectFile &In,
+                             Buffer &Out) {
   COFFReader Reader(In);
   Expected<std::unique_ptr<Object>> ObjOrErr = Reader.create();
   if (!ObjOrErr)
-    reportError(Config.InputFilename, ObjOrErr.takeError());
+    return createFileError(Config.InputFilename, ObjOrErr.takeError());
   Object *Obj = ObjOrErr->get();
   assert(Obj && "Unable to deserialize COFF object");
   if (Error E = handleArgs(Config, *Obj))
-    reportError(Config.InputFilename, std::move(E));
+    return createFileError(Config.InputFilename, std::move(E));
   COFFWriter Writer(*Obj, Out);
   if (Error E = Writer.write())
-    reportError(Config.OutputFilename, std::move(E));
+    return createFileError(Config.OutputFilename, std::move(E));
+  return Error::success();
 }
 
 } // end namespace coff