commit bc3089f45f9eda5cbe5c728cdbb09e76e1e22176
author Peter Collingbourne <peter@pcc.me.uk> Wed Aug 22 23:58:16 2018 +0000
committer Peter Collingbourne <peter@pcc.me.uk> Wed Aug 22 23:58:16 2018 +0000
tree 3a37839a68d7d656fcb24328e2ecb98590157995
parent a2761e437f220ec2cc4a5503bc427b317cc8c59d

MC: Teach the COFF object writer to write address-significance tables.

The format is the same as in ELF: a sequence of ULEB128-encoded
symbol indexes.

Differential Revision: https://reviews.llvm.org/D51047

llvm-svn: 340499

llvm/tools/llvm-readobj/COFFDumper.cpp

diff --git a/llvm/tools/llvm-readobj/COFFDumper.cpp b/llvm/tools/llvm-readobj/COFFDumper.cpp
index 0ed4ccd..c0579d6 100644
--- a/llvm/tools/llvm-readobj/COFFDumper.cpp
+++ b/llvm/tools/llvm-readobj/COFFDumper.cpp
@@ -50,6 +50,7 @@
 #include "llvm/Support/ConvertUTF.h"
 #include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/ScopedPrinter.h"
+#include "llvm/Support/LEB128.h"
 #include "llvm/Support/Win64EH.h"
 #include "llvm/Support/raw_ostream.h"
 
@@ -98,6 +99,7 @@
   mergeCodeViewTypes(llvm::codeview::MergingTypeTableBuilder &CVIDs,
                      llvm::codeview::MergingTypeTableBuilder &CVTypes) override;
   void printStackMap() const override;
+  void printAddrsig() override;
 private:
   void printSymbol(const SymbolRef &Sym);
   void printRelocation(const SectionRef &Section, const RelocationRef &Reloc,
@@ -1830,6 +1832,49 @@
                         StackMapV2Parser<support::big>(StackMapContentsArray));
 }
 
+void COFFDumper::printAddrsig() {
+  object::SectionRef AddrsigSection;
+  for (auto Sec : Obj->sections()) {
+    StringRef Name;
+    Sec.getName(Name);
+    if (Name == ".llvm_addrsig") {
+      AddrsigSection = Sec;
+      break;
+    }
+  }
+
+  if (AddrsigSection == object::SectionRef())
+    return;
+
+  StringRef AddrsigContents;
+  AddrsigSection.getContents(AddrsigContents);
+  ArrayRef<uint8_t> AddrsigContentsArray(
+      reinterpret_cast<const uint8_t*>(AddrsigContents.data()),
+      AddrsigContents.size());
+
+  ListScope L(W, "Addrsig");
+  auto *Cur = reinterpret_cast<const uint8_t *>(AddrsigContents.begin());
+  auto *End = reinterpret_cast<const uint8_t *>(AddrsigContents.end());
+  while (Cur != End) {
+    unsigned Size;
+    const char *Err;
+    uint64_t SymIndex = decodeULEB128(Cur, &Size, End, &Err);
+    if (Err)
+      reportError(Err);
+
+    Expected<COFFSymbolRef> Sym = Obj->getSymbol(SymIndex);
+    StringRef SymName;
+    std::error_code EC = errorToErrorCode(Sym.takeError());
+    if (EC || (EC = Obj->getSymbolName(*Sym, SymName))) {
+      SymName = "";
+      error(EC);
+    }
+
+    W.printNumber("Sym", SymName, SymIndex);
+    Cur += Size;
+  }
+}
+
 void llvm::dumpCodeViewMergedTypes(
     ScopedPrinter &Writer, llvm::codeview::MergingTypeTableBuilder &IDTable,
     llvm::codeview::MergingTypeTableBuilder &CVTypes) {

llvm/tools/llvm-readobj/llvm-readobj.cpp

diff --git a/llvm/tools/llvm-readobj/llvm-readobj.cpp b/llvm/tools/llvm-readobj/llvm-readobj.cpp
index a7236c0..70e925f 100644
--- a/llvm/tools/llvm-readobj/llvm-readobj.cpp
+++ b/llvm/tools/llvm-readobj/llvm-readobj.cpp
@@ -302,7 +302,7 @@
 
   cl::opt<bool> CGProfile("elf-cg-profile", cl::desc("Display callgraph profile section"));
 
-  cl::opt<bool> Addrsig("elf-addrsig",
+  cl::opt<bool> Addrsig("addrsig",
                         cl::desc("Display address-significance table"));
 
   cl::opt<OutputStyleTy>
@@ -492,6 +492,8 @@
       Dumper->printCOFFResources();
     if (opts::COFFLoadConfig)
       Dumper->printCOFFLoadConfig();
+    if (opts::Addrsig)
+      Dumper->printAddrsig();
     if (opts::CodeView)
       Dumper->printCodeViewDebugInfo();
     if (opts::CodeViewMergedTypes)