Emit DWARF info for all code section in an assembly file

Currently, when using llvm as an assembler, DWARF debug information is only
generated for the .text section. This patch modifies this so that DWARF info
is emitted for all executable sections.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211273 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 32 insertions, 17 deletions

diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index 1ba02d181d..50375d37d8 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -633,10 +633,12 @@ bool AsmParser::Run(bool NoInitialTextSection, bool NoFinalize) {
   // If we are generating dwarf for assembly source files save the initial text
   // section and generate a .file directive.
   if (getContext().getGenDwarfForAssembly()) {
-    getContext().setGenDwarfSection(getStreamer().getCurrentSection().first);
     MCSymbol *SectionStartSym = getContext().CreateTempSymbol();
     getStreamer().EmitLabel(SectionStartSym);
-    getContext().setGenDwarfSectionStartSym(SectionStartSym);
+    auto InsertResult = getContext().addGenDwarfSection(
+        getStreamer().getCurrentSection().first);
+    assert(InsertResult.second && ".text section should not have debug info yet");
+    InsertResult.first->second.first = SectionStartSym;
     getContext().setGenDwarfFileNumber(getStreamer().EmitDwarfFileDirective(
         0, StringRef(), getContext().getMainFileName()));
   }
@@ -1592,12 +1594,11 @@ bool AsmParser::parseStatement(ParseStatementInfo &Info) {
     printMessage(IDLoc, SourceMgr::DK_Note, OS.str());
   }
 
-  // If we are generating dwarf for assembly source files and the current
-  // section is the initial text section then generate a .loc directive for
-  // the instruction.
+  // If we are generating dwarf for the current section then generate a .loc
+  // directive for the instruction.
   if (!HadError && getContext().getGenDwarfForAssembly() &&
-      getContext().getGenDwarfSection() ==
-          getStreamer().getCurrentSection().first) {
+      getContext().getGenDwarfSectionSyms().count(
+        getStreamer().getCurrentSection().first)) {
 
     unsigned Line = SrcMgr.FindLineNumber(IDLoc, CurBuffer);
 
@@ -2029,7 +2030,7 @@ bool AsmParser::parseMacroArguments(const MCAsmMacro *M,
           break;
 
       if (FAI >= NParameters) {
-	assert(M && "expected macro to be defined");
+    assert(M && "expected macro to be defined");
         Error(IDLoc,
               "parameter named '" + FA.Name + "' does not exist for macro '" +
               M->Name + "'");
diff --git a/lib/MC/MCParser/ELFAsmParser.cpp b/lib/MC/MCParser/ELFAsmParser.cpp
index 78bb6c7aad..98b2b3bd60 100644
--- a/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/lib/MC/MCParser/ELFAsmParser.cpp
@@ -150,7 +150,7 @@ public:
 
 private:
   bool ParseSectionName(StringRef &SectionName);
-  bool ParseSectionArguments(bool IsPush);
+  bool ParseSectionArguments(bool IsPush, SMLoc loc);
   unsigned parseSunStyleSectionFlags();
 };
 
@@ -382,7 +382,7 @@ unsigned ELFAsmParser::parseSunStyleSectionFlags() {
 bool ELFAsmParser::ParseDirectivePushSection(StringRef s, SMLoc loc) {
   getStreamer().PushSection();
 
-  if (ParseSectionArguments(/*IsPush=*/true)) {
+  if (ParseSectionArguments(/*IsPush=*/true, loc)) {
     getStreamer().PopSection();
     return true;
   }
@@ -397,11 +397,11 @@ bool ELFAsmParser::ParseDirectivePopSection(StringRef, SMLoc) {
 }
 
 // FIXME: This is a work in progress.
-bool ELFAsmParser::ParseDirectiveSection(StringRef, SMLoc) {
-  return ParseSectionArguments(/*IsPush=*/false);
+bool ELFAsmParser::ParseDirectiveSection(StringRef, SMLoc loc) {
+  return ParseSectionArguments(/*IsPush=*/false, loc);
 }
 
-bool ELFAsmParser::ParseSectionArguments(bool IsPush) {
+bool ELFAsmParser::ParseSectionArguments(bool IsPush, SMLoc loc) {
   StringRef SectionName;
 
   if (ParseSectionName(SectionName))
@@ -545,10 +545,24 @@ EndStmt:
   }
 
   SectionKind Kind = computeSectionKind(Flags, Size);
-  getStreamer().SwitchSection(getContext().getELFSection(SectionName, Type,
-                                                         Flags, Kind, Size,
-                                                         GroupName),
-                              Subsection);
+  const MCSection *ELFSection = getContext().getELFSection(
+      SectionName, Type, Flags, Kind, Size, GroupName);
+  getStreamer().SwitchSection(ELFSection, Subsection);
+
+  if (getContext().getGenDwarfForAssembly()) {
+    auto &Sections = getContext().getGenDwarfSectionSyms();
+    auto InsertResult = Sections.insert(
+        std::make_pair(ELFSection, std::make_pair(nullptr, nullptr)));
+    if (InsertResult.second) {
+      if (getContext().getDwarfVersion() <= 2)
+        Error(loc, "DWARF2 only supports one section per compilation unit");
+
+      MCSymbol *SectionStartSymbol = getContext().CreateTempSymbol();
+      getStreamer().EmitLabel(SectionStartSymbol);
+      InsertResult.first->second.first = SectionStartSymbol;
+    }
+  }
+
   return false;
 }