1 ; RUN: opt < %s -S -instcombine | FileCheck %s 2 3 declare i32 @llvm.ctpop.i32(i32) 4 declare i8 @llvm.ctpop.i8(i8) 5 declare void @llvm.assume(i1) 6 7 define 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 16 define 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 25 define 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 39 define 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
