xref: /llvm-project/llvm/test/Transforms/InstCombine/strncmp-1.ll (revision 2caaec65c04ea7d0e9568b7895b7a46d6100cb75)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; Test that the strncmp library call simplifier works correctly.
3; RUN: opt < %s -passes=instcombine -S | FileCheck %s
4
5target 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
7@hello = constant [6 x i8] c"hello\00"
8@hell = constant [5 x i8] c"hell\00"
9@bell = constant [5 x i8] c"bell\00"
10@null = constant [1 x i8] zeroinitializer
11
12declare i32 @strncmp(ptr, ptr, i32)
13
14; strncmp("", x, n) -> -*x
15define i32 @test1(ptr %str2) {
16; CHECK-LABEL: @test1(
17; CHECK-NEXT:    [[STRCMPLOAD:%.*]] = load i8, ptr [[STR2:%.*]], align 1
18; CHECK-NEXT:    [[TMP1:%.*]] = zext i8 [[STRCMPLOAD]] to i32
19; CHECK-NEXT:    [[TEMP1:%.*]] = sub nsw i32 0, [[TMP1]]
20; CHECK-NEXT:    ret i32 [[TEMP1]]
21;
22
23  %temp1 = call i32 @strncmp(ptr @null, ptr %str2, i32 10)
24  ret i32 %temp1
25}
26
27; strncmp(x, "", n) -> *x
28define i32 @test2(ptr %str1) {
29; CHECK-LABEL: @test2(
30; CHECK-NEXT:    [[STRCMPLOAD:%.*]] = load i8, ptr [[STR1:%.*]], align 1
31; CHECK-NEXT:    [[TEMP1:%.*]] = zext i8 [[STRCMPLOAD]] to i32
32; CHECK-NEXT:    ret i32 [[TEMP1]]
33;
34
35  %temp1 = call i32 @strncmp(ptr %str1, ptr @null, i32 10)
36  ret i32 %temp1
37}
38
39; strncmp(x, y, n)  -> cnst
40define i32 @test3() {
41; CHECK-LABEL: @test3(
42; CHECK-NEXT:    ret i32 -1
43;
44
45  %temp1 = call i32 @strncmp(ptr @hell, ptr @hello, i32 10)
46  ret i32 %temp1
47}
48
49define i32 @test4() {
50; CHECK-LABEL: @test4(
51; CHECK-NEXT:    ret i32 1
52;
53
54  %temp1 = call i32 @strncmp(ptr @hell, ptr @null, i32 10)
55  ret i32 %temp1
56}
57
58define i32 @test5() {
59; CHECK-LABEL: @test5(
60; CHECK-NEXT:    ret i32 0
61;
62
63  %temp1 = call i32 @strncmp(ptr @hell, ptr @hello, i32 4)
64  ret i32 %temp1
65}
66
67; strncmp(x,y,1) -> memcmp(x,y,1)
68define i32 @test6(ptr %str1, ptr %str2) {
69; CHECK-LABEL: @test6(
70; CHECK-NEXT:    [[LHSC:%.*]] = load i8, ptr [[STR1:%.*]], align 1
71; CHECK-NEXT:    [[LHSV:%.*]] = zext i8 [[LHSC]] to i32
72; CHECK-NEXT:    [[RHSC:%.*]] = load i8, ptr [[STR2:%.*]], align 1
73; CHECK-NEXT:    [[RHSV:%.*]] = zext i8 [[RHSC]] to i32
74; CHECK-NEXT:    [[CHARDIFF:%.*]] = sub nsw i32 [[LHSV]], [[RHSV]]
75; CHECK-NEXT:    ret i32 [[CHARDIFF]]
76;
77
78  %temp1 = call i32 @strncmp(ptr %str1, ptr %str2, i32 1)
79  ret i32 %temp1
80}
81
82; strncmp(x,y,0)   -> 0
83define i32 @test7(ptr %str1, ptr %str2) {
84; CHECK-LABEL: @test7(
85; CHECK-NEXT:    ret i32 0
86;
87
88  %temp1 = call i32 @strncmp(ptr %str1, ptr %str2, i32 0)
89  ret i32 %temp1
90}
91
92; strncmp(x,x,n)  -> 0
93define i32 @test8(ptr %str, i32 %n) {
94; CHECK-LABEL: @test8(
95; CHECK-NEXT:    ret i32 0
96;
97
98  %temp1 = call i32 @strncmp(ptr %str, ptr %str, i32 %n)
99  ret i32 %temp1
100}
101
102; strncmp(nonnull x, nonnull y, n)  -> strncmp(x, y, n)
103define i32 @test9(ptr %str1, ptr %str2, i32 %n) {
104; CHECK-LABEL: @test9(
105; CHECK-NEXT:    [[TEMP1:%.*]] = call i32 @strncmp(ptr nonnull [[STR1:%.*]], ptr nonnull [[STR2:%.*]], i32 [[N:%.*]])
106; CHECK-NEXT:    ret i32 [[TEMP1]]
107;
108
109  %temp1 = call i32 @strncmp(ptr nonnull %str1, ptr nonnull %str2, i32 %n)
110  ret i32 %temp1
111}
112
113; strncmp(nonnull x, nonnull y, 0)  -> 0
114define i32 @test10(ptr %str1, ptr %str2, i32 %n) {
115; CHECK-LABEL: @test10(
116; CHECK-NEXT:    ret i32 0
117;
118
119  %temp1 = call i32 @strncmp(ptr nonnull %str1, ptr nonnull %str2, i32 0)
120  ret i32 %temp1
121}
122
123; strncmp(x, y, 5)  -> strncmp(nonnull x, nonnull y, 5)
124define i32 @test11(ptr %str1, ptr %str2, i32 %n) {
125; CHECK-LABEL: @test11(
126; CHECK-NEXT:    [[TEMP1:%.*]] = call i32 @strncmp(ptr noundef nonnull dereferenceable(1) [[STR1:%.*]], ptr noundef nonnull dereferenceable(1) [[STR2:%.*]], i32 5)
127; CHECK-NEXT:    ret i32 [[TEMP1]]
128;
129
130  %temp1 = call i32 @strncmp(ptr %str1, ptr %str2, i32 5)
131  ret i32 %temp1
132}
133
134define i32 @test12(ptr %str1, ptr %str2, i32 %n) null_pointer_is_valid {
135; CHECK-LABEL: @test12(
136; CHECK-NEXT:    [[TEMP1:%.*]] = call i32 @strncmp(ptr [[STR1:%.*]], ptr [[STR2:%.*]], i32 [[N:%.*]])
137; CHECK-NEXT:    ret i32 [[TEMP1]]
138;
139
140  %temp1 = call i32 @strncmp(ptr %str1, ptr %str2, i32 %n)
141  ret i32 %temp1
142}
143