[llvm] f75cf24 - [InstCombine] avoid crashing on vector constant expression (PR46872)

[Sanjay Patel via llvm-commits]

Author: Sanjay Patel
Date: 2020-07-28T15:02:36-04:00
New Revision: f75cf240d6ed528e1ce7770bbe09b417338b40ef

URL: https://github.com/llvm/llvm-project/commit/f75cf240d6ed528e1ce7770bbe09b417338b40ef
DIFF: https://github.com/llvm/llvm-project/commit/f75cf240d6ed528e1ce7770bbe09b417338b40ef.diff

LOG: [InstCombine] avoid crashing on vector constant expression (PR46872)

Added: 
    

Modified: 
    llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
    llvm/test/Transforms/InstCombine/vec_shuffle.ll

Removed: 
    


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diff  --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index 965a72d3a650..ceeddda05fd9 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -1599,7 +1599,7 @@ Instruction *InstCombinerImpl::foldVectorBinop(BinaryOperator &Inst) {
   Constant *C;
   if (match(&Inst,
             m_c_BinOp(m_OneUse(m_Shuffle(m_Value(V1), m_Undef(), m_Mask(Mask))),
-                      m_Constant(C))) &&
+                      m_Constant(C))) && !isa<ConstantExpr>(C) &&
       cast<FixedVectorType>(V1->getType())->getNumElements() <= NumElts) {
     assert(Inst.getType()->getScalarType() == V1->getType()->getScalarType() &&
            "Shuffle should not change scalar type");

diff  --git a/llvm/test/Transforms/InstCombine/vec_shuffle.ll b/llvm/test/Transforms/InstCombine/vec_shuffle.ll
index e7e55b07b7cd..3f3431c5d904 100644
--- a/llvm/test/Transforms/InstCombine/vec_shuffle.ll
+++ b/llvm/test/Transforms/InstCombine/vec_shuffle.ll
@@ -1745,3 +1745,18 @@ define <4 x i32> @splat_assoc_add_mul(<4 x i32> %x, <4 x i32> %y) {
   %r = mul <4 x i32> %splatx, %a
   ret <4 x i32> %r
 }
+
+
+; Do not crash on constant expressions.
+
+define <4 x i32> @PR46872(<4 x i32> %x) {
+; CHECK-LABEL: @PR46872(
+; CHECK-NEXT:    [[S:%.*]] = shufflevector <4 x i32> [[X:%.*]], <4 x i32> undef, <4 x i32> <i32 undef, i32 0, i32 1, i32 1>
+; CHECK-NEXT:    [[A:%.*]] = and <4 x i32> [[S]], bitcast (<2 x i64> <i64 ptrtoint (<4 x i32> (<4 x i32>)* @PR46872 to i64), i64 ptrtoint (<4 x i32> (<4 x i32>)* @PR46872 to i64)> to <4 x i32>)
+; CHECK-NEXT:    ret <4 x i32> [[A]]
+;
+  %s = shufflevector <4 x i32> %x, <4 x i32> undef, <4 x i32> <i32 undef, i32 0, i32 1, i32 1>
+  %a = and <4 x i32> %s, bitcast (<2 x i64> <i64 ptrtoint (<4 x i32> (<4 x i32>)* @PR46872 to i64), i64 ptrtoint (<4 x i32> (<4 x i32>)* @PR46872 to i64)> to <4 x i32>)
+  ret <4 x i32> %a
+}
+