[MIPS GlobalISel] Select G_SELECT
Add widen scalar for type index 1 (i1 condition) for G_SELECT.
Select G_SELECT for pointer, s32(integer) and smaller low level
types on MIPS32.
Differential Revision: https://reviews.llvm.org/D56001
llvm-svn: 350063
diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 274bc4b..facbafa 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -777,15 +777,18 @@
return Legalized;
case TargetOpcode::G_SELECT:
- if (TypeIdx != 0)
- return UnableToLegalize;
- // Perform operation at larger width (any extension is fine here, high bits
- // don't affect the result) and then truncate the result back to the
- // original type.
Observer.changingInstr(MI);
- widenScalarSrc(MI, WideTy, 2, TargetOpcode::G_ANYEXT);
- widenScalarSrc(MI, WideTy, 3, TargetOpcode::G_ANYEXT);
- widenScalarDst(MI, WideTy);
+ if (TypeIdx == 0) {
+ // Perform operation at larger width (any extension is fine here, high
+ // bits don't affect the result) and then truncate the result back to the
+ // original type.
+ widenScalarSrc(MI, WideTy, 2, TargetOpcode::G_ANYEXT);
+ widenScalarSrc(MI, WideTy, 3, TargetOpcode::G_ANYEXT);
+ widenScalarDst(MI, WideTy);
+ } else {
+ // Explicit extension is required here since high bits affect the result.
+ widenScalarSrc(MI, WideTy, 1, TargetOpcode::G_ZEXT);
+ }
Observer.changedInstr(MI);
return Legalized;
