Move some dwarf emission routines to AsmPrinterDwarf.cpp.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203191 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eric Christopher 2014-03-07 01:44:14 +00:00
parent 0e42ae9d8b
commit d5c1fb9676
2 changed files with 157 additions and 156 deletions

View File

@ -16,7 +16,6 @@
#include "DwarfDebug.h"
#include "DwarfException.h"
#include "WinCodeViewLineTables.h"
#include "llvm/ADT/SmallBitVector.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/ConstantFolding.h"
@ -872,161 +871,6 @@ void AsmPrinter::EmitFunctionBody() {
OutStreamer.AddBlankLine();
}
/// Emit a dwarf register operation.
static void emitDwarfRegOp(const AsmPrinter &AP, 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);
} else {
AP.OutStreamer.AddComment("DW_OP_regx");
AP.EmitInt8(dwarf::DW_OP_regx);
AP.OutStreamer.AddComment(Twine(Reg));
AP.EmitULEB128(Reg);
}
}
/// Emit an (double-)indirect dwarf register operation.
static void emitDwarfRegOpIndirect(const AsmPrinter &AP,
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);
} else {
AP.OutStreamer.AddComment("DW_OP_bregx");
AP.EmitInt8(dwarf::DW_OP_bregx);
AP.OutStreamer.AddComment(Twine(Reg));
AP.EmitULEB128(Reg);
}
AP.EmitSLEB128(Offset);
if (Deref)
AP.EmitInt8(dwarf::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, 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);
} else {
AP.OutStreamer.AddComment("DW_OP_piece");
AP.EmitInt8(dwarf::DW_OP_piece);
unsigned ByteSize = Size / 8; // Assuming 8 bits per byte.
AP.OutStreamer.AddComment(Twine(ByteSize));
AP.EmitULEB128(ByteSize);
}
}
/// Some targets do not provide a DWARF register number for every
/// 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,
const MachineLocation &MLoc) {
assert(!MLoc.isIndirect());
const TargetRegisterInfo *TRI = AP.TM.getRegisterInfo();
int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
// Walk up the super-register chain until we find a valid number.
// For example, EAX on x86_64 is a 32-bit piece of RAX with offset 0.
for (MCSuperRegIterator SR(MLoc.getReg(), TRI); SR.isValid(); ++SR) {
Reg = TRI->getDwarfRegNum(*SR, false);
if (Reg >= 0) {
unsigned Idx = TRI->getSubRegIndex(*SR, MLoc.getReg());
unsigned Size = TRI->getSubRegIdxSize(Idx);
unsigned Offset = TRI->getSubRegIdxOffset(Idx);
AP.OutStreamer.AddComment("super-register");
emitDwarfRegOp(AP, Reg);
emitDwarfOpPiece(AP, Size, Offset);
return;
}
}
// Otherwise, attempt to find a covering set of sub-register numbers.
// For example, Q0 on ARM is a composition of D0+D1.
//
// Keep track of the current position so we can emit the more
// efficient DW_OP_piece.
unsigned CurPos = 0;
// The size of the register in bits, assuming 8 bits per byte.
unsigned RegSize = TRI->getMinimalPhysRegClass(MLoc.getReg())->getSize()*8;
// Keep track of the bits in the register we already emitted, so we
// can avoid emitting redundant aliasing subregs.
SmallBitVector Coverage(RegSize, false);
for (MCSubRegIterator SR(MLoc.getReg(), TRI); SR.isValid(); ++SR) {
unsigned Idx = TRI->getSubRegIndex(MLoc.getReg(), *SR);
unsigned Size = TRI->getSubRegIdxSize(Idx);
unsigned Offset = TRI->getSubRegIdxOffset(Idx);
Reg = TRI->getDwarfRegNum(*SR, false);
// Intersection between the bits we already emitted and the bits
// covered by this subregister.
SmallBitVector Intersection(RegSize, false);
Intersection.set(Offset, Offset+Size);
Intersection ^= Coverage;
// If this sub-register has a DWARF number and we haven't covered
// 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);
CurPos = Offset+Size;
// Mark it as emitted.
Coverage.set(Offset, Offset+Size);
}
}
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);
}
}
/// EmitDwarfRegOp - Emit dwarf register operation.
void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc,
bool Indirect) const {
const TargetRegisterInfo *TRI = TM.getRegisterInfo();
int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
if (Reg < 0) {
// We assume that pointers are always in an addressable register.
if (Indirect || MLoc.isIndirect()) {
// FIXME: We have no reasonable way of handling errors in here. The
// 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);
return;
}
// Attempt to find a valid super- or sub-register.
if (!Indirect && !MLoc.isIndirect())
return EmitDwarfRegOpPiece(*this, MLoc);
}
if (MLoc.isIndirect())
emitDwarfRegOpIndirect(*this, Reg, MLoc.getOffset(), Indirect);
else if (Indirect)
emitDwarfRegOpIndirect(*this, Reg, 0, false);
else
emitDwarfRegOp(*this, Reg);
}
bool AsmPrinter::doFinalization(Module &M) {
// Emit global variables.
for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();

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@ -13,6 +13,7 @@
#define DEBUG_TYPE "asm-printer"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/ADT/SmallBitVector.h"
#include "llvm/ADT/Twine.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/MC/MCAsmInfo.h"
@ -183,6 +184,162 @@ void AsmPrinter::EmitSectionOffset(const MCSymbol *Label,
EmitLabelDifference(Label, SectionLabel, 4);
}
/// Emit a dwarf register operation.
static void emitDwarfRegOp(const AsmPrinter &AP, 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);
} else {
AP.OutStreamer.AddComment("DW_OP_regx");
AP.EmitInt8(dwarf::DW_OP_regx);
AP.OutStreamer.AddComment(Twine(Reg));
AP.EmitULEB128(Reg);
}
}
/// Emit an (double-)indirect dwarf register operation.
static void emitDwarfRegOpIndirect(const AsmPrinter &AP,
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);
} else {
AP.OutStreamer.AddComment("DW_OP_bregx");
AP.EmitInt8(dwarf::DW_OP_bregx);
AP.OutStreamer.AddComment(Twine(Reg));
AP.EmitULEB128(Reg);
}
AP.EmitSLEB128(Offset);
if (Deref)
AP.EmitInt8(dwarf::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, 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);
} else {
AP.OutStreamer.AddComment("DW_OP_piece");
AP.EmitInt8(dwarf::DW_OP_piece);
unsigned ByteSize = Size / 8; // Assuming 8 bits per byte.
AP.OutStreamer.AddComment(Twine(ByteSize));
AP.EmitULEB128(ByteSize);
}
}
/// Some targets do not provide a DWARF register number for every
/// 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,
const MachineLocation &MLoc) {
assert(!MLoc.isIndirect());
const TargetRegisterInfo *TRI = AP.TM.getRegisterInfo();
int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
// Walk up the super-register chain until we find a valid number.
// For example, EAX on x86_64 is a 32-bit piece of RAX with offset 0.
for (MCSuperRegIterator SR(MLoc.getReg(), TRI); SR.isValid(); ++SR) {
Reg = TRI->getDwarfRegNum(*SR, false);
if (Reg >= 0) {
unsigned Idx = TRI->getSubRegIndex(*SR, MLoc.getReg());
unsigned Size = TRI->getSubRegIdxSize(Idx);
unsigned Offset = TRI->getSubRegIdxOffset(Idx);
AP.OutStreamer.AddComment("super-register");
emitDwarfRegOp(AP, Reg);
emitDwarfOpPiece(AP, Size, Offset);
return;
}
}
// Otherwise, attempt to find a covering set of sub-register numbers.
// For example, Q0 on ARM is a composition of D0+D1.
//
// Keep track of the current position so we can emit the more
// efficient DW_OP_piece.
unsigned CurPos = 0;
// The size of the register in bits, assuming 8 bits per byte.
unsigned RegSize = TRI->getMinimalPhysRegClass(MLoc.getReg())->getSize()*8;
// Keep track of the bits in the register we already emitted, so we
// can avoid emitting redundant aliasing subregs.
SmallBitVector Coverage(RegSize, false);
for (MCSubRegIterator SR(MLoc.getReg(), TRI); SR.isValid(); ++SR) {
unsigned Idx = TRI->getSubRegIndex(MLoc.getReg(), *SR);
unsigned Size = TRI->getSubRegIdxSize(Idx);
unsigned Offset = TRI->getSubRegIdxOffset(Idx);
Reg = TRI->getDwarfRegNum(*SR, false);
// Intersection between the bits we already emitted and the bits
// covered by this subregister.
SmallBitVector Intersection(RegSize, false);
Intersection.set(Offset, Offset+Size);
Intersection ^= Coverage;
// If this sub-register has a DWARF number and we haven't covered
// 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);
CurPos = Offset+Size;
// Mark it as emitted.
Coverage.set(Offset, Offset+Size);
}
}
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);
}
}
/// EmitDwarfRegOp - Emit dwarf register operation.
void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc,
bool Indirect) const {
const TargetRegisterInfo *TRI = TM.getRegisterInfo();
int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
if (Reg < 0) {
// We assume that pointers are always in an addressable register.
if (Indirect || MLoc.isIndirect()) {
// FIXME: We have no reasonable way of handling errors in here. The
// 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);
return;
}
// Attempt to find a valid super- or sub-register.
if (!Indirect && !MLoc.isIndirect())
return EmitDwarfRegOpPiece(*this, MLoc);
}
if (MLoc.isIndirect())
emitDwarfRegOpIndirect(*this, Reg, MLoc.getOffset(), Indirect);
else if (Indirect)
emitDwarfRegOpIndirect(*this, Reg, 0, false);
else
emitDwarfRegOp(*this, Reg);
}
//===----------------------------------------------------------------------===//
// Dwarf Lowering Routines
//===----------------------------------------------------------------------===//