Two part patch:
First: refactor out the emission of entries into the .debug_loc section
into its own routine.
Second: add a new class ByteStreamer that can be used to either emit
using an AsmPrinter or hash using DIEHash the series of bytes that
would be emitted. Use this in all of the location emission routines
for the .debug_loc section.
No functional change intended outside of a few additional comments
in verbose assembly.
llvm-svn: 203304
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
index 3741ef0..338ed4c 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
@@ -12,6 +12,7 @@
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "asm-printer"
+#include "ByteStreamer.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/ADT/SmallBitVector.h"
#include "llvm/ADT/Twine.h"
@@ -185,58 +186,47 @@
}
/// Emit a dwarf register operation.
-static void emitDwarfRegOp(const AsmPrinter &AP, int Reg) {
+static void emitDwarfRegOp(ByteStreamer &Streamer, int Reg) {
assert(Reg >= 0);
if (Reg < 32) {
- AP.OutStreamer.AddComment(
- dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg));
- AP.EmitInt8(dwarf::DW_OP_reg0 + Reg);
+ Streamer.EmitInt8(dwarf::DW_OP_reg0 + Reg,
+ dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg));
} else {
- AP.OutStreamer.AddComment("DW_OP_regx");
- AP.EmitInt8(dwarf::DW_OP_regx);
- AP.OutStreamer.AddComment(Twine(Reg));
- AP.EmitULEB128(Reg);
+ Streamer.EmitInt8(dwarf::DW_OP_regx, "DW_OP_regx");
+ Streamer.EmitULEB128(Reg, Twine(Reg));
}
}
/// Emit an (double-)indirect dwarf register operation.
-static void emitDwarfRegOpIndirect(const AsmPrinter &AP, int Reg, int Offset,
+static void emitDwarfRegOpIndirect(ByteStreamer &Streamer, int Reg, int Offset,
bool Deref) {
assert(Reg >= 0);
if (Reg < 32) {
- AP.OutStreamer.AddComment(
- dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg));
- AP.EmitInt8(dwarf::DW_OP_breg0 + Reg);
+ Streamer.EmitInt8(dwarf::DW_OP_breg0 + Reg,
+ dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg));
} else {
- AP.OutStreamer.AddComment("DW_OP_bregx");
- AP.EmitInt8(dwarf::DW_OP_bregx);
- AP.OutStreamer.AddComment(Twine(Reg));
- AP.EmitULEB128(Reg);
+ Streamer.EmitInt8(dwarf::DW_OP_bregx, "DW_OP_bregx");
+ Streamer.EmitULEB128(Reg, Twine(Reg));
}
- AP.EmitSLEB128(Offset);
+ Streamer.EmitSLEB128(Offset);
if (Deref)
- AP.EmitInt8(dwarf::DW_OP_deref);
+ Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
}
/// Emit a dwarf register operation for describing
/// - a small value occupying only part of a register or
/// - a small register representing only part of a value.
-static void emitDwarfOpPiece(const AsmPrinter &AP, unsigned Size,
+static void emitDwarfOpPiece(ByteStreamer &Streamer, unsigned Size,
unsigned Offset) {
assert(Size > 0);
if (Offset > 0) {
- AP.OutStreamer.AddComment("DW_OP_bit_piece");
- AP.EmitInt8(dwarf::DW_OP_bit_piece);
- AP.OutStreamer.AddComment(Twine(Size));
- AP.EmitULEB128(Size);
- AP.OutStreamer.AddComment(Twine(Offset));
- AP.EmitULEB128(Offset);
+ Streamer.EmitInt8(dwarf::DW_OP_bit_piece, "DW_OP_bit_piece");
+ Streamer.EmitULEB128(Size, Twine(Size));
+ Streamer.EmitULEB128(Offset, Twine(Offset));
} else {
- AP.OutStreamer.AddComment("DW_OP_piece");
- AP.EmitInt8(dwarf::DW_OP_piece);
+ Streamer.EmitInt8(dwarf::DW_OP_piece, "DW_OP_piece");
unsigned ByteSize = Size / 8; // Assuming 8 bits per byte.
- AP.OutStreamer.AddComment(Twine(ByteSize));
- AP.EmitULEB128(ByteSize);
+ Streamer.EmitULEB128(ByteSize, Twine(ByteSize));
}
}
@@ -244,7 +234,7 @@
/// register. This function attempts to emit a dwarf register by
/// emitting a piece of a super-register or by piecing together
/// multiple subregisters that alias the register.
-static void EmitDwarfRegOpPiece(const AsmPrinter &AP,
+static void EmitDwarfRegOpPiece(ByteStreamer &Streamer, const AsmPrinter &AP,
const MachineLocation &MLoc) {
assert(!MLoc.isIndirect());
const TargetRegisterInfo *TRI = AP.TM.getRegisterInfo();
@@ -259,8 +249,8 @@
unsigned Size = TRI->getSubRegIdxSize(Idx);
unsigned Offset = TRI->getSubRegIdxOffset(Idx);
AP.OutStreamer.AddComment("super-register");
- emitDwarfRegOp(AP, Reg);
- emitDwarfOpPiece(AP, Size, Offset);
+ emitDwarfRegOp(Streamer, Reg);
+ emitDwarfOpPiece(Streamer, Size, Offset);
return;
}
}
@@ -292,8 +282,8 @@
// its range, emit a DWARF piece for it.
if (Reg >= 0 && Intersection.any()) {
AP.OutStreamer.AddComment("sub-register");
- emitDwarfRegOp(AP, Reg);
- emitDwarfOpPiece(AP, Size, Offset == CurPos ? 0 : Offset);
+ emitDwarfRegOp(Streamer, Reg);
+ emitDwarfOpPiece(Streamer, Size, Offset == CurPos ? 0 : Offset);
CurPos = Offset + Size;
// Mark it as emitted.
@@ -303,13 +293,14 @@
if (CurPos == 0) {
// FIXME: We have no reasonable way of handling errors in here.
- AP.OutStreamer.AddComment("nop (could not find a dwarf register number)");
- AP.EmitInt8(dwarf::DW_OP_nop);
+ Streamer.EmitInt8(dwarf::DW_OP_nop,
+ "nop (could not find a dwarf register number)");
}
}
/// EmitDwarfRegOp - Emit dwarf register operation.
-void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc,
+void AsmPrinter::EmitDwarfRegOp(ByteStreamer &Streamer,
+ const MachineLocation &MLoc,
bool Indirect) const {
const TargetRegisterInfo *TRI = TM.getRegisterInfo();
int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
@@ -320,23 +311,22 @@
// caller might be in the middle of a dwarf expression. We should
// probably assert that Reg >= 0 once debug info generation is more
// mature.
- OutStreamer.AddComment(
- "nop (invalid dwarf register number for indirect loc)");
- EmitInt8(dwarf::DW_OP_nop);
+ Streamer.EmitInt8(dwarf::DW_OP_nop,
+ "nop (invalid dwarf register number for indirect loc)");
return;
}
// Attempt to find a valid super- or sub-register.
if (!Indirect && !MLoc.isIndirect())
- return EmitDwarfRegOpPiece(*this, MLoc);
+ return EmitDwarfRegOpPiece(Streamer, *this, MLoc);
}
if (MLoc.isIndirect())
- emitDwarfRegOpIndirect(*this, Reg, MLoc.getOffset(), Indirect);
+ emitDwarfRegOpIndirect(Streamer, Reg, MLoc.getOffset(), Indirect);
else if (Indirect)
- emitDwarfRegOpIndirect(*this, Reg, 0, false);
+ emitDwarfRegOpIndirect(Streamer, Reg, 0, false);
else
- emitDwarfRegOp(*this, Reg);
+ emitDwarfRegOp(Streamer, Reg);
}
//===----------------------------------------------------------------------===//
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 81934e1..dab3c19 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -12,6 +12,7 @@
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "dwarfdebug"
+#include "ByteStreamer.h"
#include "DwarfDebug.h"
#include "DIE.h"
#include "DIEHash.h"
@@ -2395,6 +2396,65 @@
Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
}
+void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
+ const DotDebugLocEntry &Entry) {
+ DIVariable DV(Entry.getVariable());
+ if (Entry.isInt()) {
+ DIBasicType BTy(DV.getType());
+ if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
+ BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
+ Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
+ Streamer.EmitSLEB128(Entry.getInt());
+ } else {
+ Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
+ Streamer.EmitULEB128(Entry.getInt());
+ }
+ } else if (Entry.isLocation()) {
+ MachineLocation Loc = Entry.getLoc();
+ if (!DV.hasComplexAddress())
+ // Regular entry.
+ Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
+ else {
+ // Complex address entry.
+ unsigned N = DV.getNumAddrElements();
+ unsigned i = 0;
+ if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
+ if (Loc.getOffset()) {
+ i = 2;
+ Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
+ Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
+ Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
+ Streamer.EmitSLEB128(DV.getAddrElement(1));
+ } else {
+ // If first address element is OpPlus then emit
+ // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
+ MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
+ Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
+ i = 2;
+ }
+ } else {
+ Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
+ }
+
+ // Emit remaining complex address elements.
+ for (; i < N; ++i) {
+ uint64_t Element = DV.getAddrElement(i);
+ if (Element == DIBuilder::OpPlus) {
+ Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
+ Streamer.EmitULEB128(DV.getAddrElement(++i));
+ } else if (Element == DIBuilder::OpDeref) {
+ if (!Loc.isReg())
+ Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
+ } else
+ llvm_unreachable("unknown Opcode found in complex address");
+ }
+ }
+ }
+ // else ... ignore constant fp. There is not any good way to
+ // to represent them here in dwarf.
+ // FIXME: ^
+}
+
// Emit locations into the debug loc section.
void DwarfDebug::emitDebugLoc() {
if (DotDebugLocEntries.empty())
@@ -2422,76 +2482,24 @@
const DotDebugLocEntry &Entry = *I;
if (Entry.isMerged())
continue;
+
if (Entry.isEmpty()) {
Asm->OutStreamer.EmitIntValue(0, Size);
Asm->OutStreamer.EmitIntValue(0, Size);
Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index));
} else {
+ // Set up the range.
Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
- DIVariable DV(Entry.getVariable());
Asm->OutStreamer.AddComment("Loc expr size");
MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
Asm->EmitLabelDifference(end, begin, 2);
Asm->OutStreamer.EmitLabel(begin);
- if (Entry.isInt()) {
- DIBasicType BTy(DV.getType());
- if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
- BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
- Asm->OutStreamer.AddComment("DW_OP_consts");
- Asm->EmitInt8(dwarf::DW_OP_consts);
- Asm->EmitSLEB128(Entry.getInt());
- } else {
- Asm->OutStreamer.AddComment("DW_OP_constu");
- Asm->EmitInt8(dwarf::DW_OP_constu);
- Asm->EmitULEB128(Entry.getInt());
- }
- } else if (Entry.isLocation()) {
- MachineLocation Loc = Entry.getLoc();
- if (!DV.hasComplexAddress())
- // Regular entry.
- Asm->EmitDwarfRegOp(Loc, DV.isIndirect());
- else {
- // Complex address entry.
- unsigned N = DV.getNumAddrElements();
- unsigned i = 0;
- if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
- if (Loc.getOffset()) {
- i = 2;
- Asm->EmitDwarfRegOp(Loc, DV.isIndirect());
- Asm->OutStreamer.AddComment("DW_OP_deref");
- Asm->EmitInt8(dwarf::DW_OP_deref);
- Asm->OutStreamer.AddComment("DW_OP_plus_uconst");
- Asm->EmitInt8(dwarf::DW_OP_plus_uconst);
- Asm->EmitSLEB128(DV.getAddrElement(1));
- } else {
- // If first address element is OpPlus then emit
- // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
- MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
- Asm->EmitDwarfRegOp(TLoc, DV.isIndirect());
- i = 2;
- }
- } else {
- Asm->EmitDwarfRegOp(Loc, DV.isIndirect());
- }
-
- // 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) {
- if (!Loc.isReg())
- Asm->EmitInt8(dwarf::DW_OP_deref);
- } else
- llvm_unreachable("unknown Opcode found in complex address");
- }
- }
- }
- // else ... ignore constant fp. There is not any good way to
- // to represent them here in dwarf.
+ // Emit the entry.
+ APByteStreamer Streamer(*Asm);
+ emitDebugLocEntry(Streamer, Entry);
+ // Close the range.
Asm->OutStreamer.EmitLabel(end);
}
}
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 1373e96..0dadb73 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -31,6 +31,7 @@
namespace llvm {
+class ByteStreamer;
class DwarfUnit;
class DwarfCompileUnit;
class ConstantInt;
@@ -587,6 +588,9 @@
/// \brief Emit visible names into a debug str section.
void emitDebugStr();
+ /// \brief Emit an entry for the debug loc section.
+ void emitDebugLocEntry(ByteStreamer &Streamer, const DotDebugLocEntry &Entry);
+
/// \brief Emit visible names into a debug loc section.
void emitDebugLoc();