1; Test that the strcmp library call simplifier works correctly.
2; RUN: opt < %s -instcombine -S | FileCheck %s
3
4target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
5
6@hello = constant [6 x i8] c"hello\00"
7@hell = constant [5 x i8] c"hell\00"
8@bell = constant [5 x i8] c"bell\00"
9@null = constant [1 x i8] zeroinitializer
10
11declare i32 @strcmp(i8*, i8*)
12
13; strcmp("", x) -> -*x
14define i32 @test1(i8* %str2) {
15; CHECK-LABEL: @test1(
16; CHECK: %strcmpload = load i8, i8* %str
17; CHECK: %1 = zext i8 %strcmpload to i32
18; CHECK: %2 = sub nsw i32 0, %1
19; CHECK: ret i32 %2
20
21  %str1 = getelementptr inbounds [1 x i8], [1 x i8]* @null, i32 0, i32 0
22  %temp1 = call i32 @strcmp(i8* %str1, i8* %str2)
23  ret i32 %temp1
24
25}
26
27; strcmp(x, "") -> *x
28define i32 @test2(i8* %str1) {
29; CHECK-LABEL: @test2(
30; CHECK: %strcmpload = load i8, i8* %str
31; CHECK: %1 = zext i8 %strcmpload to i32
32; CHECK: ret i32 %1
33
34  %str2 = getelementptr inbounds [1 x i8], [1 x i8]* @null, i32 0, i32 0
35  %temp1 = call i32 @strcmp(i8* %str1, i8* %str2)
36  ret i32 %temp1
37}
38
39; strcmp(x, y)  -> cnst
40define i32 @test3() {
41; CHECK-LABEL: @test3(
42; CHECK: ret i32 -1
43
44  %str1 = getelementptr inbounds [5 x i8], [5 x i8]* @hell, i32 0, i32 0
45  %str2 = getelementptr inbounds [6 x i8], [6 x i8]* @hello, i32 0, i32 0
46  %temp1 = call i32 @strcmp(i8* %str1, i8* %str2)
47  ret i32 %temp1
48}
49
50define i32 @test4() {
51; CHECK-LABEL: @test4(
52; CHECK: ret i32 1
53
54  %str1 = getelementptr inbounds [5 x i8], [5 x i8]* @hell, i32 0, i32 0
55  %str2 = getelementptr inbounds [1 x i8], [1 x i8]* @null, i32 0, i32 0
56  %temp1 = call i32 @strcmp(i8* %str1, i8* %str2)
57  ret i32 %temp1
58}
59
60; strcmp(x, y)   -> memcmp(x, y, <known length>)
61; (This transform is rather difficult to trigger in a useful manner)
62define i32 @test5(i1 %b) {
63; CHECK-LABEL: @test5(
64; CHECK: %memcmp = call i32 @memcmp(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @hello, i32 0, i32 0), i8* %str2, i32 5)
65; CHECK: ret i32 %memcmp
66
67  %str1 = getelementptr inbounds [6 x i8], [6 x i8]* @hello, i32 0, i32 0
68  %temp1 = getelementptr inbounds [5 x i8], [5 x i8]* @hell, i32 0, i32 0
69  %temp2 = getelementptr inbounds [5 x i8], [5 x i8]* @bell, i32 0, i32 0
70  %str2 = select i1 %b, i8* %temp1, i8* %temp2
71  %temp3 = call i32 @strcmp(i8* %str1, i8* %str2)
72  ret i32 %temp3
73}
74
75; strcmp(x,x)  -> 0
76define i32 @test6(i8* %str) {
77; CHECK-LABEL: @test6(
78; CHECK: ret i32 0
79
80  %temp1 = call i32 @strcmp(i8* %str, i8* %str)
81  ret i32 %temp1
82}
83