On ELF, create relocations to the abbreviation and line sections when producing
debug info for assembly files. We were already doing the right thing when
producing debug info for C/C++.
ELF linkers don't know dwarf, so they depend on these relocations to produce
valid dwarf output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151655 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp
index 614549e..e16f7ae 100644
--- a/lib/MC/MCDwarf.cpp
+++ b/lib/MC/MCDwarf.cpp
@@ -209,7 +209,7 @@
//
// This emits the Dwarf file and the line tables.
//
-void MCDwarfFileTable::Emit(MCStreamer *MCOS) {
+const MCSymbol *MCDwarfFileTable::Emit(MCStreamer *MCOS) {
MCContext &context = MCOS->getContext();
// Switch to the section where the table will be emitted into.
MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfLineSection());
@@ -322,6 +322,8 @@
// This is the end of the section, so set the value of the symbol at the end
// of this section (that was used in a previous expression).
MCOS->EmitLabel(LineEndSym);
+
+ return LineStartSym;
}
/// Utility function to write the encoding to an object writer.
@@ -545,7 +547,9 @@
// When generating dwarf for assembly source files this emits the data for
// .debug_info section which contains three parts. The header, the compile_unit
// DIE and a list of label DIEs.
-static void EmitGenDwarfInfo(MCStreamer *MCOS) {
+static void EmitGenDwarfInfo(MCStreamer *MCOS,
+ const MCSymbol *AbbrevSectionSymbol,
+ const MCSymbol *LineSectionSymbol) {
MCContext &context = MCOS->getContext();
MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfInfoSection());
@@ -568,7 +572,11 @@
// The 4 byte offset to the debug abbrevs from the start of the .debug_abbrev,
// it is at the start of that section so this is zero.
- MCOS->EmitIntValue(0, 4);
+ if (AbbrevSectionSymbol) {
+ MCOS->EmitSymbolValue(AbbrevSectionSymbol, 4);
+ } else {
+ MCOS->EmitIntValue(0, 4);
+ }
const MCAsmInfo &asmInfo = context.getAsmInfo();
int AddrSize = asmInfo.getPointerSize();
@@ -582,7 +590,11 @@
// DW_AT_stmt_list, a 4 byte offset from the start of the .debug_line section,
// which is at the start of that section so this is zero.
- MCOS->EmitIntValue(0, 4);
+ if (LineSectionSymbol) {
+ MCOS->EmitSymbolValue(LineSectionSymbol, 4);
+ } else {
+ MCOS->EmitIntValue(0, 4);
+ }
// AT_low_pc, the first address of the default .text section.
const MCExpr *Start = MCSymbolRefExpr::Create(
@@ -686,11 +698,20 @@
// When generating dwarf for assembly source files this emits the Dwarf
// sections.
//
-void MCGenDwarfInfo::Emit(MCStreamer *MCOS) {
+void MCGenDwarfInfo::Emit(MCStreamer *MCOS, const MCSymbol *LineSectionSymbol) {
// Create the dwarf sections in this order (.debug_line already created).
MCContext &context = MCOS->getContext();
+ const MCAsmInfo &AsmInfo = context.getAsmInfo();
MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfInfoSection());
MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfAbbrevSection());
+ MCSymbol *AbbrevSectionSymbol;
+ if (AsmInfo.doesDwarfRequireRelocationForSectionOffset()) {
+ AbbrevSectionSymbol = context.CreateTempSymbol();
+ MCOS->EmitLabel(AbbrevSectionSymbol);
+ } else {
+ AbbrevSectionSymbol = NULL;
+ LineSectionSymbol = NULL;
+ }
MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfARangesSection());
// If there are no line table entries then do not emit any section contents.
@@ -704,7 +725,7 @@
EmitGenDwarfAbbrev(MCOS);
// Output the data for .debug_info section.
- EmitGenDwarfInfo(MCOS);
+ EmitGenDwarfInfo(MCOS, AbbrevSectionSymbol, LineSectionSymbol);
}
//