; RUN: opt -loop-reduce -S < %s | FileCheck %s
;
; Test LSR's use of SplitCriticalEdge during phi rewriting.
-; Verify that identical edges are merged. rdar://problem/6453893
target triple = "x86-apple-darwin"
-; CHECK: @test
+; Verify that identical edges are merged. rdar://problem/6453893
+; CHECK: @test1
; CHECK: bb89:
; CHECK: phi i8* [ %lsr.iv.next1, %bbA.bb89_crit_edge ], [ %lsr.iv.next1, %bbB.bb89_crit_edge ]{{$}}
-define i8* @test() {
+define i8* @test1() {
entry:
br label %loop
exit:
ret i8* %tmp75phi
}
+
+; Handle single-predecessor phis: PR13756
+; CHECK: @test2
+; CHECK: bb89:
+; CHECK: phi i8* [ %lsr.iv.next1, %bbA ], [ %lsr.iv.next1, %bbA ], [ %lsr.iv.next1, %bbA ]{{$}}
+define i8* @test2() {
+entry:
+ br label %loop
+
+loop:
+ %rec = phi i32 [ %next, %loop ], [ 0, %entry ]
+ %next = add i32 %rec, 1
+ %tmp75 = getelementptr i8* null, i32 %next
+ br i1 false, label %loop, label %loopexit
+
+loopexit:
+ br i1 false, label %bbA, label %bbB
+
+bbA:
+ switch i32 0, label %bb89 [
+ i32 47, label %bb89
+ i32 58, label %bb89
+ ]
+
+bbB:
+ switch i8 0, label %exit [
+ i8 47, label %exit
+ i8 58, label %exit
+ ]
+
+bb89:
+ %tmp75phi = phi i8* [ %tmp75, %bbA ], [ %tmp75, %bbA ], [ %tmp75, %bbA ]
+ br label %exit
+
+exit:
+ %result = phi i8* [ %tmp75phi, %bb89 ], [ %tmp75, %bbB ], [ %tmp75, %bbB ], [ %tmp75, %bbB ]
+ ret i8* %result
+}