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; RUN: opt < %s -S -instcombine | FileCheck %s
declare i32 @llvm.ctpop.i32(i32)
declare i8 @llvm.ctpop.i8(i8)
declare void @llvm.assume(i1)
define i1 @test1(i32 %arg) {
; CHECK: @test1
; CHECK: ret i1 false
%and = and i32 %arg, 15
%cnt = call i32 @llvm.ctpop.i32(i32 %and)
%res = icmp eq i32 %cnt, 9
ret i1 %res
}
define i1 @test2(i32 %arg) {
; CHECK: @test2
; CHECK: ret i1 false
%and = and i32 %arg, 1
%cnt = call i32 @llvm.ctpop.i32(i32 %and)
%res = icmp eq i32 %cnt, 2
ret i1 %res
}
define i1 @test3(i32 %arg) {
; CHECK: @test3
; CHECK: ret i1 false
;; Use an assume to make all the bits known without triggering constant
;; folding. This is trying to hit a corner case where we have to avoid
;; taking the log of 0.
%assume = icmp eq i32 %arg, 0
call void @llvm.assume(i1 %assume)
%cnt = call i32 @llvm.ctpop.i32(i32 %arg)
%res = icmp eq i32 %cnt, 2
ret i1 %res
}
; Negative test for when we know nothing
define i1 @test4(i8 %arg) {
; CHECK: @test4
; CHECK: ret i1 %res
%cnt = call i8 @llvm.ctpop.i8(i8 %arg)
%res = icmp eq i8 %cnt, 2
ret i1 %res
}
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