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raw | patch | inline | side by side (parent: 186abcb)
author | Rafael Espindola <rafael.espindola@gmail.com> | |
Mon, 1 Dec 2014 02:55:24 +0000 (02:55 +0000) | ||
committer | Rafael Espindola <rafael.espindola@gmail.com> | |
Mon, 1 Dec 2014 02:55:24 +0000 (02:55 +0000) |
Patch by Duncan Exon Smith with a small tweak by me.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222984 91177308-0d34-0410-b5e6-96231b3b80d8
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222984 91177308-0d34-0410-b5e6-96231b3b80d8
lib/Analysis/MemoryDependenceAnalysis.cpp | patch | blob | history | |
test/Transforms/GVN/load-from-unreachable-predecessor.ll | [new file with mode: 0644] | patch | blob |
index 187eadacd7ad3599f52844935400376eb7d024e8..ad7242136bbb7ca3ca596e4d36f7972617ba6218 100644 (file)
if (I->getBB() != BB)
continue;
- assert(I->getResult().isNonLocal() &&
+ assert((I->getResult().isNonLocal() || !DT->isReachableFromEntry(BB)) &&
"Should only be here with transparent block");
I->setResult(MemDepResult::getUnknown());
Result.push_back(NonLocalDepResult(I->getBB(), I->getResult(),
diff --git a/test/Transforms/GVN/load-from-unreachable-predecessor.ll b/test/Transforms/GVN/load-from-unreachable-predecessor.ll
--- /dev/null
@@ -0,0 +1,20 @@
+; RUN: opt -gvn -S < %s | FileCheck %s
+
+; Check that an unreachable predecessor to a PHI node doesn't cause a crash.
+; PR21625.
+
+define i32 @f(i32** %f) {
+; CHECK: bb0:
+; Load should be removed, since it's ignored.
+; CHECK-NEXT: br label
+bb0:
+ %bar = load i32** %f
+ br label %bb2
+bb1:
+ %zed = load i32** %f
+ br i1 false, label %bb1, label %bb2
+bb2:
+ %foo = phi i32* [ null, %bb0 ], [ %zed, %bb1 ]
+ %storemerge = load i32* %foo
+ ret i32 %storemerge
+}