1; RUN: opt %s -instcombine -S | FileCheck %s
2; PR5438
3
4; TODO: This should also optimize down.
5;define i32 @test1(i32 %a, i32 %b) nounwind readnone {
6;entry:
7;        %0 = icmp sgt i32 %a, -1        ; <i1> [#uses=1]
8;        %1 = icmp slt i32 %b, 0         ; <i1> [#uses=1]
9;        %2 = xor i1 %1, %0              ; <i1> [#uses=1]
10;        %3 = zext i1 %2 to i32          ; <i32> [#uses=1]
11;        ret i32 %3
12;}
13
14; TODO: This optimizes partially but not all the way.
15;define i32 @test2(i32 %a, i32 %b) nounwind readnone {
16;entry:
17;        %0 = and i32 %a, 8            ;<i32>  [#uses=1]
18;        %1 = and i32 %b, 8            ;<i32>  [#uses=1]
19;        %2 = icmp eq i32 %0, %1         ;<i1>  [#uses=1]
20;        %3 = zext i1 %2 to i32          ;<i32>  [#uses=1]
21;        ret i32 %3
22;}
23
24define i32 @test3(i32 %a, i32 %b) nounwind readnone {
25; CHECK: @test3
26entry:
27; CHECK: xor i32 %a, %b
28; CHECK: lshr i32 %0, 31
29; CHECK: xor i32 %1, 1
30        %0 = lshr i32 %a, 31            ; <i32> [#uses=1]
31        %1 = lshr i32 %b, 31            ; <i32> [#uses=1]
32        %2 = icmp eq i32 %0, %1         ; <i1> [#uses=1]
33        %3 = zext i1 %2 to i32          ; <i32> [#uses=1]
34        ret i32 %3
35; CHECK-NOT: icmp
36; CHECK-NOT: zext
37; CHECK: ret i32 %2
38}
39
40; Variation on @test3: checking the 2nd bit in a situation where the 5th bit
41; is one, not zero.
42define i32 @test3i(i32 %a, i32 %b) nounwind readnone {
43; CHECK: @test3i
44entry:
45; CHECK: xor i32 %a, %b
46; CHECK: lshr i32 %0, 31
47; CHECK: xor i32 %1, 1
48        %0 = lshr i32 %a, 29            ; <i32> [#uses=1]
49        %1 = lshr i32 %b, 29            ; <i32> [#uses=1]
50        %2 = or i32 %0, 35
51        %3 = or i32 %1, 35
52        %4 = icmp eq i32 %2, %3         ; <i1> [#uses=1]
53        %5 = zext i1 %4 to i32          ; <i32> [#uses=1]
54        ret i32 %5
55; CHECK-NOT: icmp
56; CHECK-NOT: zext
57; CHECK: ret i32 %2
58}
59