[llvm] b6c6bab - [SVE] Fix incorrect usage of getNumElements() in InstCombineCalls

[Christopher Tetreault via llvm-commits]

Author: Christopher Tetreault
Date: 2020-05-07T08:46:51-07:00
New Revision: b6c6bab9a5b4e83e14883767cc9d3fb352574878

URL: https://github.com/llvm/llvm-project/commit/b6c6bab9a5b4e83e14883767cc9d3fb352574878
DIFF: https://github.com/llvm/llvm-project/commit/b6c6bab9a5b4e83e14883767cc9d3fb352574878.diff

LOG: [SVE] Fix incorrect usage of getNumElements() in InstCombineCalls

Summary:
Remove incorrect usage of getNumElements() from visitCallInst(). The
number of elements was being used to construct a DemandedElts bitfield.
This operation does not make sense for scalable vectors. Cast to
FixedVectorType

Identified by test case Clang :: CodeGen/aarch64-sve-intrinsics/acle_sve_mla.c

Reviewers: rengolin, efriedma, sdesmalen, c-rhodes, david-arm

Reviewed By: david-arm

Subscribers: tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D79524

Added: 
    

Modified: 
    llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 2f79bc6a09a6..c57447d0c3f6 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -1942,9 +1942,10 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
     if (Changed) return II;
   }
 
-  // For vector result intrinsics, use the generic demanded vector support.
-  if (auto *IIVTy = dyn_cast<VectorType>(II->getType())) {
-    auto VWidth = IIVTy->getNumElements();
+  // For fixed width vector result intrinsics, use the generic demanded vector
+  // support.
+  if (auto *IIFVTy = dyn_cast<FixedVectorType>(II->getType())) {
+    auto VWidth = IIFVTy->getNumElements();
     APInt UndefElts(VWidth, 0);
     APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
     if (Value *V = SimplifyDemandedVectorElts(II, AllOnesEltMask, UndefElts)) {