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1; RUN: opt < %s -S -instcombine | FileCheck %s
2
3declare i32 @llvm.ctpop.i32(i32)
4declare i8 @llvm.ctpop.i8(i8)
5declare void @llvm.assume(i1)
6
7define i1 @test1(i32 %arg) {
8; CHECK: @test1
9; CHECK: ret i1 false
10  %and = and i32 %arg, 15
11  %cnt = call i32 @llvm.ctpop.i32(i32 %and)
12  %res = icmp eq i32 %cnt, 9
13  ret i1 %res
14}
15
16define i1 @test2(i32 %arg) {
17; CHECK: @test2
18; CHECK: ret i1 false
19  %and = and i32 %arg, 1
20  %cnt = call i32 @llvm.ctpop.i32(i32 %and)
21  %res = icmp eq i32 %cnt, 2
22  ret i1 %res
23}
24
25define i1 @test3(i32 %arg) {
26; CHECK: @test3
27; CHECK: ret i1 false
28  ;; Use an assume to make all the bits known without triggering constant
29  ;; folding.  This is trying to hit a corner case where we have to avoid
30  ;; taking the log of 0.
31  %assume = icmp eq i32 %arg, 0
32  call void @llvm.assume(i1 %assume)
33  %cnt = call i32 @llvm.ctpop.i32(i32 %arg)
34  %res = icmp eq i32 %cnt, 2
35  ret i1 %res
36}
37
38; Negative test for when we know nothing
39define i1 @test4(i8 %arg) {
40; CHECK: @test4
41; CHECK: ret i1 %res
42  %cnt = call i8 @llvm.ctpop.i8(i8 %arg)
43  %res = icmp eq i8 %cnt, 2
44  ret i1 %res
45}
46