1 ; Test that the strncmp library call simplifier works correctly.
2 ; RUN: opt < %s -instcombine -S | FileCheck %s
4 target 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"
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
11 declare i32 @strncmp(i8*, i8*, i32)
13 ; strncmp("", x, n) -> -*x
14 define i32 @test1(i8* %str2) {
16 ; CHECK: %strcmpload = load i8* %str
17 ; CHECK: %1 = zext i8 %strcmpload to i32
18 ; CHECK: %2 = sub i32 0, %1
21 %str1 = getelementptr inbounds [1 x i8]* @null, i32 0, i32 0
22 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 10)
26 ; strncmp(x, "", n) -> *x
27 define i32 @test2(i8* %str1) {
29 ; CHECK: %strcmpload = load i8* %str1
30 ; CHECK: %1 = zext i8 %strcmpload to i32
33 %str2 = getelementptr inbounds [1 x i8]* @null, i32 0, i32 0
34 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 10)
38 ; strncmp(x, y, n) -> cnst
43 %str1 = getelementptr inbounds [5 x i8]* @hell, i32 0, i32 0
44 %str2 = getelementptr inbounds [6 x i8]* @hello, i32 0, i32 0
45 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 10)
53 %str1 = getelementptr inbounds [5 x i8]* @hell, i32 0, i32 0
54 %str2 = getelementptr inbounds [1 x i8]* @null, i32 0, i32 0
55 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 10)
63 %str1 = getelementptr inbounds [5 x i8]* @hell, i32 0, i32 0
64 %str2 = getelementptr inbounds [6 x i8]* @hello, i32 0, i32 0
65 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 4)
69 ; strncmp(x,y,1) -> memcmp(x,y,1)
70 ; TODO: Once the memcmp simplifier gets moved into the instcombine pass
71 ; the following memcmp will be folded into two loads and a subtract.
72 define i32 @test6(i8* %str1, i8* %str2) {
74 ; CHECK: call i32 @memcmp
75 ; CHECK: ret i32 %memcmp
77 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 1)
82 define i32 @test7(i8* %str1, i8* %str2) {
86 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 0)
91 define i32 @test8(i8* %str, i32 %n) {
95 %temp1 = call i32 @strncmp(i8* %str, i8* %str, i32 %n)