xref: /llvm-project/llvm/test/Transforms/InstCombine/memrchr-4.ll (revision 10f315dc9c96ec2413881ab55a285e35d80def88)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=instcombine -S | FileCheck %s
3;
4; Verify that memrchr calls with a string consisting of all the same
5; characters are folded and those with mixed strings are not.
6
7declare ptr @memrchr(ptr, i32, i64)
8
9@a11111 = constant [5 x i8] c"\01\01\01\01\01"
10@a1110111 = constant [7 x i8] c"\01\01\01\00\01\01\01"
11
12
13; Fold memrchr(a11111, C, 5) to *a11111 == C ? a11111 + 5 - 1 : null.
14
15define ptr @fold_memrchr_a11111_c_5(i32 %C) {
16; CHECK-LABEL: @fold_memrchr_a11111_c_5(
17; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[C:%.*]] to i8
18; CHECK-NEXT:    [[TMP2:%.*]] = icmp eq i8 [[TMP1]], 1
19; CHECK-NEXT:    [[MEMRCHR_SEL:%.*]] = select i1 [[TMP2]], ptr getelementptr inbounds nuw (i8, ptr @a11111, i64 4), ptr null
20; CHECK-NEXT:    ret ptr [[MEMRCHR_SEL]]
21;
22
23  %ret = call ptr @memrchr(ptr @a11111, i32 %C, i64 5)
24  ret ptr %ret
25}
26
27
28; Fold memrchr(a11111, C, N) to N && *a11111 == C ? a11111 + N - 1 : null,
29; on the assumption that N is in bounds.
30
31define ptr @fold_memrchr_a11111_c_n(i32 %C, i64 %N) {
32; CHECK-LABEL: @fold_memrchr_a11111_c_n(
33; CHECK-NEXT:    [[TMP1:%.*]] = icmp ne i64 [[N:%.*]], 0
34; CHECK-NEXT:    [[TMP2:%.*]] = trunc i32 [[C:%.*]] to i8
35; CHECK-NEXT:    [[TMP3:%.*]] = icmp eq i8 [[TMP2]], 1
36; CHECK-NEXT:    [[TMP4:%.*]] = select i1 [[TMP1]], i1 [[TMP3]], i1 false
37; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr i8, ptr @a11111, i64 [[N]]
38; CHECK-NEXT:    [[MEMRCHR_PTR_PLUS:%.*]] = getelementptr i8, ptr [[TMP5]], i64 -1
39; CHECK-NEXT:    [[MEMRCHR_SEL:%.*]] = select i1 [[TMP4]], ptr [[MEMRCHR_PTR_PLUS]], ptr null
40; CHECK-NEXT:    ret ptr [[MEMRCHR_SEL]]
41;
42
43  %ret = call ptr @memrchr(ptr @a11111, i32 %C, i64 %N)
44  ret ptr %ret
45}
46
47
48; Fold memrchr(a1110111, C, 3) to a1110111[2] == C ? a1110111 + 2 : null.
49
50define ptr @fold_memrchr_a1110111_c_3(i32 %C) {
51; CHECK-LABEL: @fold_memrchr_a1110111_c_3(
52; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[C:%.*]] to i8
53; CHECK-NEXT:    [[TMP2:%.*]] = icmp eq i8 [[TMP1]], 1
54; CHECK-NEXT:    [[MEMRCHR_SEL:%.*]] = select i1 [[TMP2]], ptr getelementptr inbounds nuw (i8, ptr @a1110111, i64 2), ptr null
55; CHECK-NEXT:    ret ptr [[MEMRCHR_SEL]]
56;
57
58  %ret = call ptr @memrchr(ptr @a1110111, i32 %C, i64 3)
59  ret ptr %ret
60}
61
62
63; Don't fold memrchr(a1110111, C, 4).
64
65define ptr @call_memrchr_a1110111_c_4(i32 %C) {
66; CHECK-LABEL: @call_memrchr_a1110111_c_4(
67; CHECK-NEXT:    [[RET:%.*]] = call ptr @memrchr(ptr noundef nonnull dereferenceable(4) @a1110111, i32 [[C:%.*]], i64 4)
68; CHECK-NEXT:    ret ptr [[RET]]
69;
70
71  %ret = call ptr @memrchr(ptr @a1110111, i32 %C, i64 4)
72  ret ptr %ret
73}
74
75
76; Don't fold memrchr(a1110111, C, 7).
77
78define ptr @call_memrchr_a1110111_c_7(i32 %C) {
79; CHECK-LABEL: @call_memrchr_a1110111_c_7(
80; CHECK-NEXT:    [[RET:%.*]] = call ptr @memrchr(ptr noundef nonnull dereferenceable(7) @a1110111, i32 [[C:%.*]], i64 7)
81; CHECK-NEXT:    ret ptr [[RET]]
82;
83
84  %ret = call ptr @memrchr(ptr @a1110111, i32 %C, i64 7)
85  ret ptr %ret
86}
87
88
89; Don't fold memrchr(a1110111, C, N).
90
91define ptr @call_memrchr_a1110111_c_n(i32 %C, i64 %N) {
92; CHECK-LABEL: @call_memrchr_a1110111_c_n(
93; CHECK-NEXT:    [[RET:%.*]] = call ptr @memrchr(ptr nonnull @a1110111, i32 [[C:%.*]], i64 [[N:%.*]])
94; CHECK-NEXT:    ret ptr [[RET]]
95;
96
97  %ret = call ptr @memrchr(ptr @a1110111, i32 %C, i64 %N)
98  ret ptr %ret
99}
100