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.

llvm-svn: 211273

1 files changed, 23 insertions, 9 deletions

diff --git a/llvm/lib/MC/MCParser/ELFAsmParser.cpp b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
index 78bb6c7..98b2b3b 100644
--- a/llvm/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/llvm/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;
 }