GlobalISel: Fix not calling observer when legalizing bitcount ops
This was hiding bugs from never legalizing the source type.
llvm-svn: 353102
diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 28c103a0..cd8c8f8 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -1083,23 +1083,27 @@
case TargetOpcode::G_CTLZ_ZERO_UNDEF:
case TargetOpcode::G_CTPOP: {
if (TypeIdx == 0) {
+ Observer.changingInstr(MI);
widenScalarDst(MI, WideTy, 0);
+ Observer.changedInstr(MI);
return Legalized;
}
+ unsigned SrcReg = MI.getOperand(1).getReg();
+
// First ZEXT the input.
- auto MIBSrc = MIRBuilder.buildZExt(WideTy, MI.getOperand(1).getReg());
- LLT CurTy = MRI.getType(MI.getOperand(0).getReg());
+ auto MIBSrc = MIRBuilder.buildZExt(WideTy, SrcReg);
+ LLT CurTy = MRI.getType(SrcReg);
if (MI.getOpcode() == TargetOpcode::G_CTTZ) {
// The count is the same in the larger type except if the original
// value was zero. This can be handled by setting the bit just off
// the top of the original type.
auto TopBit =
APInt::getOneBitSet(WideTy.getSizeInBits(), CurTy.getSizeInBits());
- MIBSrc = MIRBuilder.buildInstr(
- TargetOpcode::G_OR, {WideTy},
- {MIBSrc, MIRBuilder.buildConstant(WideTy, TopBit.getSExtValue())});
+ MIBSrc = MIRBuilder.buildOr(
+ WideTy, MIBSrc, MIRBuilder.buildConstant(WideTy, TopBit));
}
+
// Perform the operation at the larger size.
auto MIBNewOp = MIRBuilder.buildInstr(MI.getOpcode(), {WideTy}, {MIBSrc});
// This is already the correct result for CTPOP and CTTZs
@@ -1111,12 +1115,9 @@
TargetOpcode::G_SUB, {WideTy},
{MIBNewOp, MIRBuilder.buildConstant(WideTy, SizeDiff)});
}
- auto &TII = *MI.getMF()->getSubtarget().getInstrInfo();
- // Make the original instruction a trunc now, and update its source.
- Observer.changingInstr(MI);
- MI.setDesc(TII.get(TargetOpcode::G_TRUNC));
- MI.getOperand(1).setReg(MIBNewOp->getOperand(0).getReg());
- Observer.changedInstr(MI);
+
+ MIRBuilder.buildZExtOrTrunc(MI.getOperand(0), MIBNewOp);
+ MI.eraseFromParent();
return Legalized;
}
case TargetOpcode::G_BSWAP: {
