Properly constrain register classes in 2-addr.
X86 has 2-addr instructions with different constraints on the tied def
and use operands. One is GR32, one is GR32_NOSP.
llvm-svn: 157149
diff --git a/llvm/lib/CodeGen/TwoAddressInstructionPass.cpp b/llvm/lib/CodeGen/TwoAddressInstructionPass.cpp
index 8164690..5218aa1 100644
--- a/llvm/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/llvm/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -1555,6 +1555,12 @@
MO.setIsKill(false);
RemovedKillFlag = true;
}
+
+ // Make sure regA is a legal regclass for the SrcIdx operand.
+ if (TargetRegisterInfo::isVirtualRegister(regA) &&
+ TargetRegisterInfo::isVirtualRegister(regB))
+ MRI->constrainRegClass(regA, MRI->getRegClass(regB));
+
MO.setReg(regA);
if (isCopy)