xref: /llvm-project/llvm/test/Transforms/InstCombine/strcmp-1.ll (revision 2caaec65c04ea7d0e9568b7895b7a46d6100cb75)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; Test that the strcmp library call simplifier works correctly.
3; RUN: opt < %s -passes=instcombine -S | FileCheck %s --check-prefix=NOBCMP
4; RUN: opt < %s -passes=instcombine -mtriple=unknown-unknown-linux-gnu -S | FileCheck %s --check-prefix=BCMP
5
6target 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"
7
8@hello = constant [6 x i8] c"hello\00"
9@hell = constant [5 x i8] c"hell\00"
10@bell = constant [5 x i8] c"bell\00"
11@null = constant [1 x i8] zeroinitializer
12
13declare i32 @strcmp(ptr, ptr)
14
15; strcmp("", x) -> -*x
16define i32 @test1(ptr %str2) {
17; CHECK-LABEL: @test1(
18; CHECK: %strcmpload = load i8, ptr %str
19; CHECK: %1 = zext i8 %strcmpload to i32
20; CHECK: %2 = sub nsw i32 0, %1
21; CHECK: ret i32 %2
22; NOBCMP-LABEL: @test1(
23; NOBCMP-NEXT:    [[STRCMPLOAD:%.*]] = load i8, ptr [[STR2:%.*]], align 1
24; NOBCMP-NEXT:    [[TMP1:%.*]] = zext i8 [[STRCMPLOAD]] to i32
25; NOBCMP-NEXT:    [[TEMP1:%.*]] = sub nsw i32 0, [[TMP1]]
26; NOBCMP-NEXT:    ret i32 [[TEMP1]]
27;
28; BCMP-LABEL: @test1(
29; BCMP-NEXT:    [[STRCMPLOAD:%.*]] = load i8, ptr [[STR2:%.*]], align 1
30; BCMP-NEXT:    [[TMP1:%.*]] = zext i8 [[STRCMPLOAD]] to i32
31; BCMP-NEXT:    [[TEMP1:%.*]] = sub nsw i32 0, [[TMP1]]
32; BCMP-NEXT:    ret i32 [[TEMP1]]
33;
34  %temp1 = call i32 @strcmp(ptr @null, ptr %str2)
35  ret i32 %temp1
36
37}
38
39; strcmp(x, "") -> *x
40define i32 @test2(ptr %str1) {
41; CHECK-LABEL: @test2(
42; CHECK: %strcmpload = load i8, ptr %str
43; CHECK: %1 = zext i8 %strcmpload to i32
44; CHECK: ret i32 %1
45; NOBCMP-LABEL: @test2(
46; NOBCMP-NEXT:    [[STRCMPLOAD:%.*]] = load i8, ptr [[STR1:%.*]], align 1
47; NOBCMP-NEXT:    [[TEMP1:%.*]] = zext i8 [[STRCMPLOAD]] to i32
48; NOBCMP-NEXT:    ret i32 [[TEMP1]]
49;
50; BCMP-LABEL: @test2(
51; BCMP-NEXT:    [[STRCMPLOAD:%.*]] = load i8, ptr [[STR1:%.*]], align 1
52; BCMP-NEXT:    [[TEMP1:%.*]] = zext i8 [[STRCMPLOAD]] to i32
53; BCMP-NEXT:    ret i32 [[TEMP1]]
54;
55  %temp1 = call i32 @strcmp(ptr %str1, ptr @null)
56  ret i32 %temp1
57}
58
59; strcmp(x, y)  -> cnst
60define i32 @test3() {
61; CHECK-LABEL: @test3(
62; CHECK: ret i32 -1
63; NOBCMP-LABEL: @test3(
64; NOBCMP-NEXT:    ret i32 -1
65;
66; BCMP-LABEL: @test3(
67; BCMP-NEXT:    ret i32 -1
68;
69  %temp1 = call i32 @strcmp(ptr @hell, ptr @hello)
70  ret i32 %temp1
71}
72
73define i32 @test4() {
74; CHECK-LABEL: @test4(
75; CHECK: ret i32 1
76; NOBCMP-LABEL: @test4(
77; NOBCMP-NEXT:    ret i32 1
78;
79; BCMP-LABEL: @test4(
80; BCMP-NEXT:    ret i32 1
81;
82  %temp1 = call i32 @strcmp(ptr @hell, ptr @null)
83  ret i32 %temp1
84}
85
86; strcmp(x, y)   -> memcmp(x, y, <known length>)
87; (This transform is rather difficult to trigger in a useful manner)
88define i32 @test5(i1 %b) {
89; CHECK-LABEL: @test5(
90; CHECK: %memcmp = call i32 @memcmp(ptr @hello, ptr %str2, i32 5)
91; CHECK: ret i32 %memcmp
92; NOBCMP-LABEL: @test5(
93; NOBCMP-NEXT:    [[STR2:%.*]] = select i1 [[B:%.*]], ptr @hell, ptr @bell
94; NOBCMP-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(ptr noundef nonnull dereferenceable(5) @hello, ptr noundef nonnull dereferenceable(5) [[STR2]], i32 5)
95; NOBCMP-NEXT:    ret i32 [[MEMCMP]]
96;
97; BCMP-LABEL: @test5(
98; BCMP-NEXT:    [[STR2:%.*]] = select i1 [[B:%.*]], ptr @hell, ptr @bell
99; BCMP-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(ptr noundef nonnull dereferenceable(5) @hello, ptr noundef nonnull dereferenceable(5) [[STR2]], i32 5)
100; BCMP-NEXT:    ret i32 [[MEMCMP]]
101;
102  %str2 = select i1 %b, ptr @hell, ptr @bell
103  %temp3 = call i32 @strcmp(ptr @hello, ptr %str2)
104  ret i32 %temp3
105}
106
107; strcmp(x,x)  -> 0
108define i32 @test6(ptr %str) {
109; CHECK-LABEL: @test6(
110; CHECK: ret i32 0
111; NOBCMP-LABEL: @test6(
112; NOBCMP-NEXT:    ret i32 0
113;
114; BCMP-LABEL: @test6(
115; BCMP-NEXT:    ret i32 0
116;
117  %temp1 = call i32 @strcmp(ptr %str, ptr %str)
118  ret i32 %temp1
119}
120
121; strcmp(x, y) == 0  -> bcmp(x, y, <known length>)
122define i1 @test7(i1 %b) {
123; NOBCMP-LABEL: @test7(
124; NOBCMP-NEXT:    [[STR2:%.*]] = select i1 [[B:%.*]], ptr @hell, ptr @bell
125; NOBCMP-NEXT:    [[MEMCMP:%.*]] = call i32 @memcmp(ptr noundef nonnull dereferenceable(5) @hello, ptr noundef nonnull dereferenceable(5) [[STR2]], i32 5)
126; NOBCMP-NEXT:    [[RES:%.*]] = icmp eq i32 [[MEMCMP]], 0
127; NOBCMP-NEXT:    ret i1 [[RES]]
128;
129; BCMP-LABEL: @test7(
130; BCMP-NEXT:    [[STR2:%.*]] = select i1 [[B:%.*]], ptr @hell, ptr @bell
131; BCMP-NEXT:    [[BCMP:%.*]] = call i32 @bcmp(ptr noundef nonnull dereferenceable(5) @hello, ptr noundef nonnull dereferenceable(5) [[STR2]], i32 5)
132; BCMP-NEXT:    [[RES:%.*]] = icmp eq i32 [[BCMP]], 0
133; BCMP-NEXT:    ret i1 [[RES]]
134;
135
136
137  %str2 = select i1 %b, ptr @hell, ptr @bell
138  %temp3 = call i32 @strcmp(ptr @hello, ptr %str2)
139  %res = icmp eq i32 %temp3, 0
140  ret i1 %res
141}
142