[X86] Check destination element type before forming VTRUNCS/VTRUNCUS …

…in combineTruncateWithSat. Fixes crash reported here https://reviews.llvm.org/D73607 Using a store to keep the trunc intact. Returning v16i24 would cause the trunc to be optimized away in SelectionDAGBuilder. Reviewed By: RKSimon Differential Revision: https://reviews.llvm.org/D103940
llvm · Jun 9, 2021 · 765ef4b · 765ef4b
1 parent dd763ac
commit 765ef4b
Show file tree

Hide file tree

Showing 2 changed files with 677 additions and 1 deletion.
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -45273,7 +45273,8 @@ static SDValue combineTruncateWithSat(SDValue In, EVT VT, const SDLoc &DL,
 
   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
   if (TLI.isTypeLegal(InVT) && InVT.isVector() && SVT != MVT::i1 &&
-      Subtarget.hasAVX512() && (InSVT != MVT::i16 || Subtarget.hasBWI())) {
+      Subtarget.hasAVX512() && (InSVT != MVT::i16 || Subtarget.hasBWI()) &&
+      (SVT == MVT::i32 || SVT == MVT::i16 || SVT == MVT::i8)) {
     unsigned TruncOpc = 0;
     SDValue SatVal;
     if (auto SSatVal = detectSSatPattern(In, VT)) {