Fix pr3954. The register scavenger asserts for inline assembly with
register destinations that are tied to source operands. The
TargetInstrDescr::findTiedToSrcOperand method silently fails for inline
assembly. The existing MachineInstr::isRegReDefinedByTwoAddr was very
close to doing what is needed, so this revision makes a few changes to
that method and also renames it to isRegTiedToUseOperand (for consistency
with the very similar isRegTiedToDefOperand and because it handles both
two-address instructions and inline assembly with tied registers).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68714 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/Spiller.cpp b/lib/CodeGen/Spiller.cpp
index 7b2a32f..354ff0a 100644
--- a/lib/CodeGen/Spiller.cpp
+++ b/lib/CodeGen/Spiller.cpp
@@ -1589,8 +1589,8 @@
// If this def is part of a two-address operand, make sure to execute
// the store from the correct physical register.
unsigned PhysReg;
- int TiedOp = MI.getDesc().findTiedToSrcOperand(i);
- if (TiedOp != -1) {
+ unsigned TiedOp;
+ if (MI.isRegTiedToUseOperand(i, &TiedOp)) {
PhysReg = MI.getOperand(TiedOp).getReg();
if (SubIdx) {
unsigned SuperReg = findSuperReg(RC, PhysReg, SubIdx, TRI);