[codeview] Emit S_BUILDINFO and LF_BUILDINFO with cwd and source file
Summary: We can fill in the command line and compiler path later if we want.
Reviewers: zturner
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D53179
llvm-svn: 344393
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index 8232f07..3b503b6 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -561,6 +561,11 @@
OS.AddComment("String table");
OS.EmitCVStringTableDirective();
+ // Emit S_BUILDINFO, which points to LF_BUILDINFO. Put this in its own symbol
+ // subsection in the generic .debug$S section at the end. There is no
+ // particular reason for this ordering other than to match MSVC.
+ emitBuildInfo();
+
// Emit type information and hashes last, so that any types we translate while
// emitting function info are included.
emitTypeInformation();
@@ -772,6 +777,49 @@
OS.EmitLabel(CompilerEnd);
}
+static TypeIndex getStringIdTypeIdx(GlobalTypeTableBuilder &TypeTable,
+ StringRef S) {
+ StringIdRecord SIR(TypeIndex(0x0), S);
+ return TypeTable.writeLeafType(SIR);
+}
+
+void CodeViewDebug::emitBuildInfo() {
+ // First, make LF_BUILDINFO. It's a sequence of strings with various bits of
+ // build info. The known prefix is:
+ // - Absolute path of current directory
+ // - Compiler path
+ // - Main source file path, relative to CWD or absolute
+ // - Type server PDB file
+ // - Canonical compiler command line
+ // If frontend and backend compilation are separated (think llc or LTO), it's
+ // not clear if the compiler path should refer to the executable for the
+ // frontend or the backend. Leave it blank for now.
+ TypeIndex BuildInfoArgs[BuildInfoRecord::MaxArgs] = {};
+ NamedMDNode *CUs = MMI->getModule()->getNamedMetadata("llvm.dbg.cu");
+ const MDNode *Node = *CUs->operands().begin(); // FIXME: Multiple CUs.
+ const auto *CU = cast<DICompileUnit>(Node);
+ const DIFile *MainSourceFile = CU->getFile();
+ BuildInfoArgs[BuildInfoRecord::CurrentDirectory] =
+ getStringIdTypeIdx(TypeTable, MainSourceFile->getDirectory());
+ BuildInfoArgs[BuildInfoRecord::SourceFile] =
+ getStringIdTypeIdx(TypeTable, MainSourceFile->getFilename());
+ // FIXME: Path to compiler and command line. PDB is intentionally blank unless
+ // we implement /Zi type servers.
+ BuildInfoRecord BIR(BuildInfoArgs);
+ TypeIndex BuildInfoIndex = TypeTable.writeLeafType(BIR);
+
+ // Make a new .debug$S subsection for the S_BUILDINFO record, which points
+ // from the module symbols into the type stream.
+ MCSymbol *BuildInfoEnd = beginCVSubsection(DebugSubsectionKind::Symbols);
+ OS.AddComment("Record length");
+ OS.EmitIntValue(6, 2);
+ OS.AddComment("Record kind: S_BUILDINFO");
+ OS.EmitIntValue(unsigned(SymbolKind::S_BUILDINFO), 2);
+ OS.AddComment("LF_BUILDINFO index");
+ OS.EmitIntValue(BuildInfoIndex.getIndex(), 4);
+ endCVSubsection(BuildInfoEnd);
+}
+
void CodeViewDebug::emitInlineeLinesSubsection() {
if (InlinedSubprograms.empty())
return;