[AArch64][GISel] fix G_ADD*/G_SUB* legalization
widenScalarDst updates the insert point to after MI, so
widenScalarSrc must be called before widenScalarDst. Otherwise
The updated Src values will appear after MI and break SSA. e.g.:
%14:_(s64), %15:_(s1) = G_UADDE %9:_, %11:_, %13:_
becomes
%14:_(s64), %16:_(s32) = G_UADDE %9:_, %11:_, %17:_
%15:_(s1) = G_TRUNC %16:_(s32)
%17:_(s32) = G_ZEXT %13:_(s1)
Differential Revision: https://reviews.llvm.org/D132547
Change-Id: Ie3458747a6879433f4d5ab9939d2bd102dd0f2db
diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index a7d74bf..5179631 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -1888,9 +1888,9 @@
unsigned BoolExtOp = MIRBuilder.getBoolExtOp(WideTy.isVector(), false);
Observer.changingInstr(MI);
- widenScalarDst(MI, WideTy, 1);
if (CarryIn)
widenScalarSrc(MI, WideTy, 4, BoolExtOp);
+ widenScalarDst(MI, WideTy, 1);
Observer.changedInstr(MI);
return Legalized;