Make sure the regs are low regs for tMUL size reduction.

llvm-svn: 151318
This commit is contained in:
Jim Grosbach 2012-02-24 00:53:11 +00:00
parent 4ff2fb2fbc
commit 2f070e028c

View File

@ -599,7 +599,12 @@ Thumb2SizeReduce::ReduceTo2Addr(MachineBasicBlock &MBB, MachineInstr *MI,
unsigned Reg1 = MI->getOperand(1).getReg();
// t2MUL is "special". The tied source operand is second, not first.
if (MI->getOpcode() == ARM::t2MUL) {
if (Reg0 != MI->getOperand(2).getReg()) {
unsigned Reg2 = MI->getOperand(2).getReg();
// Early exit if the regs aren't all low regs.
if (!isARMLowRegister(Reg0) || !isARMLowRegister(Reg1)
|| !isARMLowRegister(Reg2))
return false;
if (Reg0 != Reg2) {
// If the other operand also isn't the same as the destination, we
// can't reduce.
if (Reg1 != Reg0)