First part of support for generating dwarf for assembly source files with the

-g flag.  In this part we generate the .file for the source being assembled and
the .loc's for the assembled instructions.

The next part will be to generate the dwarf Compile Unit DIE and a dwarf
subprogram DIE for each non-temporary label.

Once the next part is done test cases will be added.  rdar://9275556

llvm-svn: 143509

1 files changed, 24 insertions, 0 deletions

diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index d7ee1c4ca3e..990fd17f598 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -464,6 +464,14 @@ bool AsmParser::Run(bool NoInitialTextSection, bool NoFinalize) {
   HadError = false;
   AsmCond StartingCondState = TheCondState;
 
+  // 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());
+    getStreamer().EmitDwarfFileDirective(getContext().nextGenDwarfFileNumber(),
+      StringRef(), SrcMgr.getMemoryBuffer(CurBuffer)->getBufferIdentifier());
+  }
+
   // While we have input, parse each statement.
   while (Lexer.isNot(AsmToken::Eof)) {
     if (!ParseStatement()) continue;
@@ -1211,6 +1219,18 @@ bool AsmParser::ParseStatement() {
     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 (!HadError && getContext().getGenDwarfForAssembly() &&
+      getContext().getGenDwarfSection() == getStreamer().getCurrentSection() ) {
+    getStreamer().EmitDwarfLocDirective(getContext().getGenDwarfFileNumber(),
+                                        SrcMgr.FindLineNumber(IDLoc, CurBuffer),
+                                        0, DWARF2_LINE_DEFAULT_IS_STMT ?
+					DWARF2_FLAG_IS_STMT : 0, 0, 0,
+                                        StringRef());
+  }
+
   // If parsing succeeded, match the instruction.
   if (!HadError)
     HadError = getTargetParser().MatchAndEmitInstruction(IDLoc, ParsedOperands,
@@ -2342,6 +2362,10 @@ bool GenericAsmParser::ParseDirectiveFile(StringRef, SMLoc DirectiveLoc) {
   if (getLexer().isNot(AsmToken::EndOfStatement))
     return TokError("unexpected token in '.file' directive");
 
+  if (getContext().getGenDwarfForAssembly() == true)
+    Error(DirectiveLoc, "input can't have .file dwarf directives when -g is "
+                        "used to generate dwarf debug info for assembly code");
+
   if (FileNumber == -1)
     getStreamer().EmitFileDirective(Filename);
   else {