Make GVN look through extractvalues for recognised intrinsics. GVN can then CSE ops that match values produced by the intrinsics.

llvm-svn: 134677

1 files changed, 47 insertions, 0 deletions

diff --git a/llvm/test/Transforms/GVN/2011-07-07-MatchIntrinsicExtract.ll b/llvm/test/Transforms/GVN/2011-07-07-MatchIntrinsicExtract.ll
new file mode 100644
index 00000000000..a2ef4ab4185
--- /dev/null
+++ b/llvm/test/Transforms/GVN/2011-07-07-MatchIntrinsicExtract.ll
@@ -0,0 +1,47 @@
+; RUN: opt < %s -gvn -S | FileCheck %s
+;
+
+%0 = type { i64, i1 }
+
+define i64 @test1(i64 %a, i64 %b) nounwind ssp {
+entry:
+  %uadd = tail call %0 @llvm.uadd.with.overflow.i64(i64 %a, i64 %b)
+  %uadd.0 = extractvalue %0 %uadd, 0
+  %add1 = add i64 %a, %b
+  ret i64 %add1
+}
+
+; CHECK: @test1
+; CHECK-NOT: add1
+; CHECK: ret
+
+define i64 @test2(i64 %a, i64 %b) nounwind ssp {
+entry:
+  %usub = tail call %0 @llvm.usub.with.overflow.i64(i64 %a, i64 %b)
+  %usub.0 = extractvalue %0 %usub, 0
+  %sub1 = sub i64 %a, %b
+  ret i64 %sub1
+}
+
+; CHECK: @test2
+; CHECK-NOT: sub1
+; CHECK: ret
+
+define i64 @test3(i64 %a, i64 %b) nounwind ssp {
+entry:
+  %umul = tail call %0 @llvm.umul.with.overflow.i64(i64 %a, i64 %b)
+  %umul.0 = extractvalue %0 %umul, 0
+  %mul1 = mul i64 %a, %b
+  ret i64 %mul1
+}
+
+; CHECK: @test3
+; CHECK-NOT: mul1
+; CHECK: ret
+
+
+declare void @exit(i32) noreturn
+declare %0 @llvm.uadd.with.overflow.i64(i64, i64) nounwind readnone
+declare %0 @llvm.usub.with.overflow.i64(i64, i64) nounwind readnone
+declare %0 @llvm.umul.with.overflow.i64(i64, i64) nounwind readnone
+