Teach dwarf writer to handle complex address expression for .debug_loc entries.
This fixes clang generated blocks' variables' debug info.
Radar 9279956.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130373 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index d99faf9..26da800 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -1466,7 +1466,7 @@
}
// The value is valid until the next DBG_VALUE or clobber.
- DotDebugLocEntries.push_back(DotDebugLocEntry(FLabel, SLabel, MLoc));
+ DotDebugLocEntries.push_back(DotDebugLocEntry(FLabel, SLabel, MLoc, Var));
}
DotDebugLocEntries.push_back(DotDebugLocEntry());
}
@@ -2721,7 +2721,39 @@
} else {
Asm->OutStreamer.EmitSymbolValue(Entry.Begin, Size, 0);
Asm->OutStreamer.EmitSymbolValue(Entry.End, Size, 0);
- Asm->EmitDwarfRegOp(Entry.Loc);
+ DIVariable DV(Entry.Variable);
+ if (DV.hasComplexAddress()) {
+ unsigned N = DV.getNumAddrElements();
+ unsigned i = 0;
+ Asm->OutStreamer.AddComment("Loc expr size");
+ if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
+ // If first address element is OpPlus then emit
+ // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
+ MachineLocation Loc(Entry.Loc.getReg(), DV.getAddrElement(1));
+ Asm->EmitInt16(Asm->getDwarfRegOpSize(Loc) + N - 2);
+ Asm->EmitDwarfRegOp(Loc);
+// Asm->EmitULEB128(DV.getAddrElement(1));
+ i = 2;
+ } else {
+ Asm->EmitInt16(Asm->getDwarfRegOpSize(Entry.Loc) + N);
+ Asm->EmitDwarfRegOp(Entry.Loc);
+ }
+
+ // Emit remaining complex address elements.
+ for (; i < N; ++i) {
+ uint64_t Element = DV.getAddrElement(i);
+ if (Element == DIBuilder::OpPlus) {
+ Asm->EmitInt8(dwarf::DW_OP_plus_uconst);
+ Asm->EmitULEB128(DV.getAddrElement(++i));
+ } else if (Element == DIBuilder::OpDeref)
+ Asm->EmitInt8(dwarf::DW_OP_deref);
+ else llvm_unreachable("unknown Opcode found in complex address");
+ }
+ } else {
+ Asm->OutStreamer.AddComment("Loc expr size");
+ Asm->EmitInt16(Asm->getDwarfRegOpSize(Entry.Loc));
+ Asm->EmitDwarfRegOp(Entry.Loc);
+ }
}
}
}