[llvm] r211801 - GVN: Preserve invariant.load metadata
Arnold Schwaighofer
aschwaighofer at apple.com
Thu Jun 26 12:51:19 PDT 2014
Author: arnolds
Date: Thu Jun 26 14:51:19 2014
New Revision: 211801
URL: http://llvm.org/viewvc/llvm-project?rev=211801&view=rev
Log:
GVN: Preserve invariant.load metadata
If both instructions to be replaced are marked invariant the resulting
instruction is invariant.
rdar://13358910
Fix by Erik Eckstein!
Added:
llvm/trunk/test/Transforms/GVN/invariant-load.ll
Modified:
llvm/trunk/lib/Transforms/Scalar/GVN.cpp
Modified: llvm/trunk/lib/Transforms/Scalar/GVN.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/GVN.cpp?rev=211801&r1=211800&r2=211801&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/GVN.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/GVN.cpp Thu Jun 26 14:51:19 2014
@@ -1798,6 +1798,10 @@ static void patchReplacementInstruction(
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;
}
}
}
Added: llvm/trunk/test/Transforms/GVN/invariant-load.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/GVN/invariant-load.ll?rev=211801&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/GVN/invariant-load.ll (added)
+++ llvm/trunk/test/Transforms/GVN/invariant-load.ll Thu Jun 26 14:51:19 2014
@@ -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 !{ }
+
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