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-rw-r--r--lib/Transforms/Scalar/GVN.cpp4
-rw-r--r--test/Transforms/GVN/invariant-load.ll30
2 files changed, 34 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index 56781d44aa..106eba099c 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -1798,6 +1798,10 @@ static void patchReplacementInstruction(Instruction *I, Value *Repl) {
case LLVMContext::MD_fpmath:
ReplInst->setMetadata(Kind, MDNode::getMostGenericFPMath(IMD, ReplMD));
break;
+ case LLVMContext::MD_invariant_load:
+ // Only set the !invariant.load if it is present in both instructions.
+ ReplInst->setMetadata(Kind, IMD);
+ break;
}
}
}
diff --git a/test/Transforms/GVN/invariant-load.ll b/test/Transforms/GVN/invariant-load.ll
new file mode 100644
index 0000000000..73a12787fb
--- /dev/null
+++ b/test/Transforms/GVN/invariant-load.ll
@@ -0,0 +1,30 @@
+; RUN: opt -basicaa -gvn -S < %s | FileCheck %s
+
+define i32 @test1(i32* nocapture %p, i8* nocapture %q) {
+; CHECK-LABEL: test1
+; CHECK: %x = load i32* %p, align 4, !invariant.load !0
+; CHECK-NOT: %y = load
+entry:
+ %x = load i32* %p, align 4, !invariant.load !0
+ %conv = trunc i32 %x to i8
+ store i8 %conv, i8* %q, align 1
+ %y = load i32* %p, align 4, !invariant.load !0
+ %add = add i32 %y, 1
+ ret i32 %add
+}
+
+define i32 @test2(i32* nocapture %p, i8* nocapture %q) {
+; CHECK-LABEL: test2
+; CHECK-NOT: !invariant.load
+; CHECK-NOT: %y = load
+entry:
+ %x = load i32* %p, align 4
+ %conv = trunc i32 %x to i8
+ store i8 %conv, i8* %q, align 1
+ %y = load i32* %p, align 4, !invariant.load !0
+ %add = add i32 %y, 1
+ ret i32 %add
+}
+
+!0 = metadata !{ }
+