[DebugInfo] Support for debug_macinfo.dwo section in llvm and llvm-dwarfdump.

This patch adds support for debug_macinfo.dwo section[pre-standardized]
to llvm and llvm-dwarfdump.

Reviewers: probinson, dblaikie, aprantl, jini.susan.george, alok

Differential Revision: https://reviews.llvm.org/D70705

Tags: #debug-info #llvm

1 files changed, 24 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 551e8a2751b..e689c08acf2 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -1169,7 +1169,7 @@ void DwarfDebug::finalizeModuleInfo() {
 
     auto *CUNode = cast<DICompileUnit>(P.first);
     // If compile Unit has macros, emit "DW_AT_macro_info" attribute.
-    if (CUNode->getMacros())
+    if (CUNode->getMacros() && !useSplitDwarf())
       U.addSectionLabel(U.getUnitDie(), dwarf::DW_AT_macro_info,
                         U.getMacroLabelBegin(),
                         TLOF.getDwarfMacinfoSection()->getBeginSymbol());
@@ -1227,8 +1227,12 @@ void DwarfDebug::endModule() {
   // Emit info into a debug ranges section.
   emitDebugRanges();
 
+  if (useSplitDwarf())
+  // Emit info into a debug macinfo.dwo section.
+    emitDebugMacinfoDWO();
+  else
   // Emit info into a debug macinfo section.
-  emitDebugMacinfo();
+    emitDebugMacinfo();
 
   if (useSplitDwarf()) {
     emitDebugStrDWO();
@@ -2783,6 +2787,24 @@ void DwarfDebug::emitDebugMacinfo() {
   }
 }
 
+void DwarfDebug::emitDebugMacinfoDWO() {
+  for (const auto &P : CUMap) {
+    auto &TheCU = *P.second;
+    auto *SkCU = TheCU.getSkeleton();
+    DwarfCompileUnit &U = SkCU ? *SkCU : TheCU;
+    auto *CUNode = cast<DICompileUnit>(P.first);
+    DIMacroNodeArray Macros = CUNode->getMacros();
+    if (Macros.empty())
+      continue;
+    Asm->OutStreamer->SwitchSection(
+        Asm->getObjFileLowering().getDwarfMacinfoDWOSection());
+    Asm->OutStreamer->EmitLabel(U.getMacroLabelBegin());
+    handleMacroNodes(Macros, U);
+    Asm->OutStreamer->AddComment("End Of Macro List Mark");
+    Asm->emitInt8(0);
+  }
+}
+
 // DWARF5 Experimental Separate Dwarf emitters.
 
 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,