Enhance the sinking code to handle diamond patterns. Patch by
Carlo Alberto Ferraris.
llvm-svn: 157736
diff --git a/llvm/test/Transforms/Sink/basic.ll b/llvm/test/Transforms/Sink/basic.ll
index 4c531d8..1d0b6b5 100644
--- a/llvm/test/Transforms/Sink/basic.ll
+++ b/llvm/test/Transforms/Sink/basic.ll
@@ -36,3 +36,29 @@
false:
ret i32 0
}
+
+; Sink to the nearest post-dominator
+
+; CHECK: @diamond
+; CHECK: X:
+; CHECK-NEXT: phi
+; CHECK-NEXT: mul nsw
+; CHECK-NEXT: sub
+
+define i32 @diamond(i32 %a, i32 %b, i32 %c) {
+ %1 = mul nsw i32 %c, %b
+ %2 = icmp sgt i32 %a, 0
+ br i1 %2, label %B0, label %B1
+
+B0: ; preds = %0
+ br label %X
+
+B1: ; preds = %0
+ br label %X
+
+X: ; preds = %5, %3
+ %.01 = phi i32 [ %c, %B0 ], [ %a, %B1 ]
+ %R = sub i32 %1, %.01
+ ret i32 %R
+}
+