Unify internal representation of ARM instructions with a register right-shifted by #32. These are stored as shifts by #0 in the MCInst and correctly marshalled when transforming from or to assembly representation.
llvm-svn: 155565
diff --git a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index 3fe681f..69c9d45 100644
--- a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -1446,8 +1446,10 @@
assert(isRegShiftedImm() &&
"addRegShiftedImmOperands() on non RegShiftedImm!");
Inst.addOperand(MCOperand::CreateReg(RegShiftedImm.SrcReg));
+ // Shift of #32 is encoded as 0 where permitted
+ unsigned Imm = (RegShiftedImm.ShiftImm == 32 ? 0 : RegShiftedImm.ShiftImm);
Inst.addOperand(MCOperand::CreateImm(
- ARM_AM::getSORegOpc(RegShiftedImm.ShiftTy, RegShiftedImm.ShiftImm)));
+ ARM_AM::getSORegOpc(RegShiftedImm.ShiftTy, Imm)));
}
void addShifterImmOperands(MCInst &Inst, unsigned N) const {
@@ -6809,6 +6811,9 @@
// A shift by zero is a plain MOVr, not a MOVsi.
unsigned Amt = Inst.getOperand(2).getImm();
unsigned Opc = Amt == 0 ? ARM::MOVr : ARM::MOVsi;
+ // A shift by 32 should be encoded as 0 when permitted
+ if (Amt == 32 && (ShiftTy == ARM_AM::lsr || ShiftTy == ARM_AM::asr))
+ Amt = 0;
unsigned Shifter = ARM_AM::getSORegOpc(ShiftTy, Amt);
MCInst TmpInst;
TmpInst.setOpcode(Opc);
@@ -7154,7 +7159,9 @@
}
case ARM::MOVsi: {
ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(Inst.getOperand(2).getImm());
- if (SOpc == ARM_AM::rrx) return false;
+ // rrx shifts and asr/lsr of #32 is encoded as 0
+ if (SOpc == ARM_AM::rrx || SOpc == ARM_AM::asr || SOpc == ARM_AM::lsr)
+ return false;
if (ARM_AM::getSORegOffset(Inst.getOperand(2).getImm()) == 0) {
// Shifting by zero is accepted as a vanilla 'MOVr'
MCInst TmpInst;