diff --git a/lib/CodeGen/AsmPrinter/DwarfExpression.cpp b/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
index 4c16ae70d1f344147d134c92acd91977568db65c..eb101ca2dcbbeee70ee45ee63f284a560e39d43b 100644 (file)
//===----------------------------------------------------------------------===//
#include "DwarfExpression.h"
-
#include "DwarfDebug.h"
#include "llvm/ADT/SmallBitVector.h"
#include "llvm/CodeGen/AsmPrinter.h"
return true;
}
-void DwarfExpression::AddMachineRegPiece(unsigned MachineReg,
+bool DwarfExpression::AddMachineRegPiece(unsigned MachineReg,
unsigned PieceSizeInBits,
unsigned PieceOffsetInBits) {
const TargetRegisterInfo *TRI = getTRI();
AddReg(Reg);
if (PieceSizeInBits)
AddOpPiece(PieceSizeInBits, PieceOffsetInBits);
- return;
+ return true;
}
// Walk up the super-register chain until we find a valid number.
AddShr(RegOffset);
AddOpPiece(Size, PieceOffsetInBits);
}
- return;
+ return true;
}
}
}
}
- if (CurPos == PieceOffsetInBits)
- // FIXME: We have no reasonable way of handling errors in here.
- EmitOp(dwarf::DW_OP_nop, "nop (could not find a dwarf register number)");
+ return CurPos > PieceOffsetInBits;
}
void DwarfExpression::AddSignedConstant(int Value) {
return OffsetInBits;
}
-void DwarfExpression::AddMachineRegExpression(DIExpression Expr,
+bool DwarfExpression::AddMachineRegExpression(DIExpression Expr,
unsigned MachineReg,
unsigned PieceOffsetInBits) {
- unsigned N = Expr.getNumElements();
- unsigned I = 0;
+ auto I = Expr.begin();
// Pattern-match combinations for which more efficient representations exist
// first.
- if (N >= 3 && Expr.getElement(0) == dwarf::DW_OP_piece) {
+ if (I == Expr.end())
+ return AddMachineRegPiece(MachineReg);
+
+ bool ValidReg = false;
+ switch (*I) {
+ case dwarf::DW_OP_piece: {
unsigned SizeOfByte = 8;
- unsigned OffsetInBits = Expr.getElement(1) * SizeOfByte;
- unsigned SizeInBits = Expr.getElement(2) * SizeOfByte;
- AddMachineRegPiece(MachineReg, SizeInBits,
- getOffsetOrZero(OffsetInBits, PieceOffsetInBits));
- I = 3;
- } else if (N >= 3 && Expr.getElement(0) == dwarf::DW_OP_plus &&
- Expr.getElement(2) == dwarf::DW_OP_deref) {
+ unsigned OffsetInBits = I.getArg(1) * SizeOfByte;
+ unsigned SizeInBits = I.getArg(2) * SizeOfByte;
+ // Piece always comes at the end of the expression.
+ return AddMachineRegPiece(MachineReg, SizeInBits,
+ getOffsetOrZero(OffsetInBits, PieceOffsetInBits));
+ }
+ case dwarf::DW_OP_plus:
// [DW_OP_reg,Offset,DW_OP_plus,DW_OP_deref] --> [DW_OP_breg,Offset].
- unsigned Offset = Expr.getElement(1);
- AddMachineRegIndirect(MachineReg, Offset);
- I = 3;
- } else if (N >= 1 && Expr.getElement(0) == dwarf::DW_OP_deref) {
+ if (*std::next(I) == dwarf::DW_OP_deref) {
+ unsigned Offset = I.getArg(1);
+ ValidReg = AddMachineRegIndirect(MachineReg, Offset);
+ std::advance(I, 2);
+ break;
+ } else
+ ValidReg = AddMachineRegPiece(MachineReg);
+ case dwarf::DW_OP_deref:
// [DW_OP_reg,DW_OP_deref] --> [DW_OP_breg].
- AddMachineRegIndirect(MachineReg);
- I = 1;
- } else
- AddMachineRegPiece(MachineReg);
+ ValidReg = AddMachineRegIndirect(MachineReg);
+ ++I;
+ break;
+ default:
+ llvm_unreachable("unsupported operand");
+ }
+
+ if (!ValidReg)
+ return false;
// Emit remaining elements of the expression.
- AddExpression(Expr, I);
+ AddExpression(I, PieceOffsetInBits);
+ return true;
}
-void DwarfExpression::AddExpression(DIExpression Expr, unsigned I,
+void DwarfExpression::AddExpression(DIExpression::iterator I,
unsigned PieceOffsetInBits) {
- unsigned N = Expr.getNumElements();
- for (; I < N; ++I) {
- switch (Expr.getElement(I)) {
+ for (; I != DIExpression::iterator(); ++I) {
+ switch (*I) {
case dwarf::DW_OP_piece: {
unsigned SizeOfByte = 8;
- unsigned OffsetInBits = Expr.getElement(++I) * SizeOfByte;
- unsigned SizeInBits = Expr.getElement(++I) * SizeOfByte;
+ unsigned OffsetInBits = I.getArg(1) * SizeOfByte;
+ unsigned SizeInBits = I.getArg(2) * SizeOfByte;
AddOpPiece(SizeInBits, getOffsetOrZero(OffsetInBits, PieceOffsetInBits));
break;
}
case dwarf::DW_OP_plus:
EmitOp(dwarf::DW_OP_plus_uconst);
- EmitUnsigned(Expr.getElement(++I));
+ EmitUnsigned(I.getArg(1));
break;
case dwarf::DW_OP_deref:
EmitOp(dwarf::DW_OP_deref);