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-rw-r--r--lib/Analysis/ValueTracking.cpp2
-rw-r--r--test/Transforms/InstSimplify/compare.ll11
2 files changed, 13 insertions, 0 deletions
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index 45b75df..45dcc5e 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -953,6 +953,8 @@ bool llvm::isKnownNonZero(Value *V, const DataLayout *TD, unsigned Depth) {
// Check for pointer simplifications.
if (V->getType()->isPointerTy()) {
+ if (isKnownNonNull(V))
+ return true;
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V))
if (isGEPKnownNonNull(GEP, TD, Depth))
return true;
diff --git a/test/Transforms/InstSimplify/compare.ll b/test/Transforms/InstSimplify/compare.ll
index 0ecfb1f..b764c76 100644
--- a/test/Transforms/InstSimplify/compare.ll
+++ b/test/Transforms/InstSimplify/compare.ll
@@ -682,3 +682,14 @@ define zeroext i1 @external_compare(i32* noalias %x) {
; CHECK: external_compare
; CHECK: ret i1 %cmp
}
+
+define i1 @alloca_gep(i64 %a, i64 %b) {
+; CHECK: @alloca_gep
+; We can prove this GEP is non-null because it is inbounds and the pointer
+; is non-null.
+ %strs = alloca [1000 x [1001 x i8]], align 16
+ %x = getelementptr inbounds [1000 x [1001 x i8]]* %strs, i64 0, i64 %a, i64 %b
+ %cmp = icmp eq i8* %x, null
+ ret i1 %cmp
+; CHECK-NEXT: ret i1 false
+}