From: Igor Laevsky <igmyrj@gmail.com>
Date: Thu, 7 Dec 2017 15:00:52 +0000 (+0000)
Subject: [InstCombine] Don't crash on out of bounds index in the insertelement
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e18338969d0ed13427863fb23fa4a5c8e8df0b14;p=llvm

[InstCombine] Don't crash on out of bounds index in the insertelement

Differential Revision: https://reviews.llvm.org/D40390



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320049 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/InstCombine/InstCombineVectorOps.cpp b/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
index 6c99007475c..65a96b96522 100644
--- a/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
+++ b/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
@@ -781,6 +781,10 @@ Instruction *InstCombiner::visitInsertElementInst(InsertElementInst &IE) {
   Value *ScalarOp = IE.getOperand(1);
   Value *IdxOp    = IE.getOperand(2);
 
+  if (auto *V = SimplifyInsertElementInst(
+          VecOp, ScalarOp, IdxOp, SQ.getWithInstruction(&IE)))
+    return replaceInstUsesWith(IE, V);
+
   // Inserting an undef or into an undefined place, remove this.
   if (isa<UndefValue>(ScalarOp) || isa<UndefValue>(IdxOp))
     replaceInstUsesWith(IE, VecOp);
diff --git a/test/Transforms/InstCombine/out-of-bounds-indexes.ll b/test/Transforms/InstCombine/out-of-bounds-indexes.ll
index a1887d27550..02be57a4d15 100644
--- a/test/Transforms/InstCombine/out-of-bounds-indexes.ll
+++ b/test/Transforms/InstCombine/out-of-bounds-indexes.ll
@@ -31,3 +31,11 @@ define i128 @test_non64bit(i128 %a) {
 }
 
 declare void @llvm.assume(i1)
+
+define <4 x double> @inselt_bad_index(<4 x double> %a) {
+; CHECK-LABEL: @inselt_bad_index(
+; CHECK-NEXT:    ret <4 x double> undef
+;
+  %I = insertelement <4 x double> %a, double 0.0, i64 4294967296
+  ret <4 x double> %I
+}
diff --git a/test/Transforms/InstCombine/vector_insertelt_shuffle.ll b/test/Transforms/InstCombine/vector_insertelt_shuffle.ll
index c358509d690..41c6370e48e 100644
--- a/test/Transforms/InstCombine/vector_insertelt_shuffle.ll
+++ b/test/Transforms/InstCombine/vector_insertelt_shuffle.ll
@@ -54,10 +54,10 @@ define <4 x float> @bazz(<4 x float> %x, i32 %a) {
   ret <4 x float> %ins6
 }
 
+; Out of bounds index folds to undef
 define <4 x float> @bazzz(<4 x float> %x) {
 ; CHECK-LABEL: @bazzz(
-; CHECK-NEXT:    [[INS2:%.*]] = insertelement <4 x float> %x, float 2.000000e+00, i32 2
-; CHECK-NEXT:    ret <4 x float> [[INS2]]
+; CHECK-NEXT:   ret <4 x float> <float undef, float undef, float 2.000000e+00, float undef>
 ;
   %ins1 = insertelement<4 x float> %x, float 1.0, i32 5
   %ins2 = insertelement<4 x float> %ins1, float 2.0, i32 2