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1; RUN: opt < %s -gvn -S | FileCheck %s
2; This testcase tests insertion of no-cost phis.  That is,
3; when the value is already available in every predecessor,
4; and we just need to insert a phi node to merge the available values.
5
6@c = global i32 0, align 4
7@d = global i32 0, align 4
8
9
10define i32 @mai(i32 %foo, i32 %a, i32 %b) {
11  %1 = icmp ne i32 %foo, 0
12  br i1 %1, label %bb1, label %bb2
13
14bb1:
15  %2 = add nsw i32 %a, %b
16  store i32 %2, i32* @c, align 4
17  br label %mergeblock
18
19bb2:
20  %3 = add nsw i32 %a, %b
21  store i32 %3, i32* @d, align 4
22  br label %mergeblock
23
24mergeblock:
25; CHECK: pre-phi = phi i32 [ %3, %bb2 ], [ %2, %bb1 ]
26; CHECK-NEXT: ret i32 %.pre-phi
27  %4 = add nsw i32 %a, %b
28  ret i32 %4
29}
30
31
32