; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -passes=instcombine -S | FileCheck %s ; ; Verify that memchr calls with a string consisting of all the same ; characters are folded and those with mixed strings are not. declare i8* @memchr(i8*, i32, i64) @a00000 = constant [5 x i8] zeroinitializer @a11111 = constant [5 x i8] c"\01\01\01\01\01" @a111122 = constant [6 x i8] c"\01\01\01\01\02\02" @a1110111 = constant [7 x i8] c"\01\01\01\00\01\01\01" ; Fold memchr(a00000, C, 5) to *a00000 == C ? a00000 : null. ; TODO: This depends on getConstantStringInfo() being able to handle ; implicitly zeroed out constants. define i8* @fold_memchr_a00000_c_5(i32 %C) { ; CHECK-LABEL: @fold_memchr_a00000_c_5( ; CHECK-NEXT: [[RET:%.*]] = call i8* @memchr(i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([5 x i8], [5 x i8]* @a00000, i64 0, i64 0), i32 [[C:%.*]], i64 5) ; CHECK-NEXT: ret i8* [[RET]] ; %ptr = getelementptr [5 x i8], [5 x i8]* @a00000, i64 0, i64 0 %ret = call i8* @memchr(i8* %ptr, i32 %C, i64 5) ret i8* %ret } ; Fold memchr(a11111, C, 5) to *a11111 == C ? a11111 : null. define i8* @fold_memchr_a11111_c_5(i32 %C) { ; CHECK-LABEL: @fold_memchr_a11111_c_5( ; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[C:%.*]] to i8 ; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i8 [[TMP1]], 1 ; CHECK-NEXT: [[MEMCHR_SEL2:%.*]] = select i1 [[TMP2]], i8* getelementptr inbounds ([5 x i8], [5 x i8]* @a11111, i64 0, i64 0), i8* null ; CHECK-NEXT: ret i8* [[MEMCHR_SEL2]] ; %ptr = getelementptr [5 x i8], [5 x i8]* @a11111, i64 0, i64 0 %ret = call i8* @memchr(i8* %ptr, i32 %C, i64 5) ret i8* %ret } ; Fold memchr(a11111, C, N) to N && *a11111 == C ? a11111 : null, ; on the assumption that N is in bounds. define i8* @fold_memchr_a11111_c_n(i32 %C, i64 %N) { ; CHECK-LABEL: @fold_memchr_a11111_c_n( ; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[C:%.*]] to i8 ; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i8 [[TMP1]], 1 ; CHECK-NEXT: [[TMP3:%.*]] = icmp ne i64 [[N:%.*]], 0 ; CHECK-NEXT: [[TMP4:%.*]] = and i1 [[TMP3]], [[TMP2]] ; CHECK-NEXT: [[MEMCHR_SEL2:%.*]] = select i1 [[TMP4]], i8* getelementptr inbounds ([5 x i8], [5 x i8]* @a11111, i64 0, i64 0), i8* null ; CHECK-NEXT: ret i8* [[MEMCHR_SEL2]] ; %ptr = getelementptr [5 x i8], [5 x i8]* @a11111, i64 0, i64 0 %ret = call i8* @memchr(i8* %ptr, i32 %C, i64 %N) ret i8* %ret } ; Fold memchr(a111122, C, N) to ; N != 0 && C == 1 ? a111122 : N > 4 && C == 2 ? a111122 + 4 : null. define i8* @fold_memchr_a111122_c_n(i32 %C, i64 %N) { ; CHECK-LABEL: @fold_memchr_a111122_c_n( ; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[C:%.*]] to i8 ; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i8 [[TMP1]], 2 ; CHECK-NEXT: [[TMP3:%.*]] = icmp ugt i64 [[N:%.*]], 4 ; CHECK-NEXT: [[TMP4:%.*]] = and i1 [[TMP2]], [[TMP3]] ; CHECK-NEXT: [[MEMCHR_SEL1:%.*]] = select i1 [[TMP4]], i8* getelementptr inbounds ([6 x i8], [6 x i8]* @a111122, i64 0, i64 4), i8* null ; CHECK-NEXT: [[TMP5:%.*]] = icmp eq i8 [[TMP1]], 1 ; CHECK-NEXT: [[TMP6:%.*]] = icmp ne i64 [[N]], 0 ; CHECK-NEXT: [[TMP7:%.*]] = and i1 [[TMP6]], [[TMP5]] ; CHECK-NEXT: [[MEMCHR_SEL2:%.*]] = select i1 [[TMP7]], i8* getelementptr inbounds ([6 x i8], [6 x i8]* @a111122, i64 0, i64 0), i8* [[MEMCHR_SEL1]] ; CHECK-NEXT: ret i8* [[MEMCHR_SEL2]] ; %ptr = getelementptr [6 x i8], [6 x i8]* @a111122, i64 0, i64 0 %ret = call i8* @memchr(i8* %ptr, i32 %C, i64 %N) ret i8* %ret } ; Fold memchr(a1110111, C, 3) to a1110111[2] == C ? a1110111 : null. define i8* @fold_memchr_a1110111_c_3(i32 %C) { ; CHECK-LABEL: @fold_memchr_a1110111_c_3( ; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[C:%.*]] to i8 ; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i8 [[TMP1]], 1 ; CHECK-NEXT: [[MEMCHR_SEL2:%.*]] = select i1 [[TMP2]], i8* getelementptr inbounds ([7 x i8], [7 x i8]* @a1110111, i64 0, i64 0), i8* null ; CHECK-NEXT: ret i8* [[MEMCHR_SEL2]] ; %ptr = getelementptr [7 x i8], [7 x i8]* @a1110111, i64 0, i64 0 %ret = call i8* @memchr(i8* %ptr, i32 %C, i64 3) ret i8* %ret } ; Don't fold memchr(a1110111, C, 4). define i8* @call_memchr_a1110111_c_4(i32 %C) { ; CHECK-LABEL: @call_memchr_a1110111_c_4( ; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[C:%.*]] to i8 ; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i8 [[TMP1]], 0 ; CHECK-NEXT: [[MEMCHR_SEL1:%.*]] = select i1 [[TMP2]], i8* getelementptr inbounds ([7 x i8], [7 x i8]* @a1110111, i64 0, i64 3), i8* null ; CHECK-NEXT: [[TMP3:%.*]] = icmp eq i8 [[TMP1]], 1 ; CHECK-NEXT: [[MEMCHR_SEL2:%.*]] = select i1 [[TMP3]], i8* getelementptr inbounds ([7 x i8], [7 x i8]* @a1110111, i64 0, i64 0), i8* [[MEMCHR_SEL1]] ; CHECK-NEXT: ret i8* [[MEMCHR_SEL2]] ; %ptr = getelementptr [7 x i8], [7 x i8]* @a1110111, i64 0, i64 0 %ret = call i8* @memchr(i8* %ptr, i32 %C, i64 4) ret i8* %ret } ; Don't fold memchr(a1110111, C, 7). define i8* @call_memchr_a1110111_c_7(i32 %C) { ; CHECK-LABEL: @call_memchr_a1110111_c_7( ; CHECK-NEXT: [[RET:%.*]] = call i8* @memchr(i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([7 x i8], [7 x i8]* @a1110111, i64 0, i64 0), i32 [[C:%.*]], i64 7) ; CHECK-NEXT: ret i8* [[RET]] ; %ptr = getelementptr [7 x i8], [7 x i8]* @a1110111, i64 0, i64 0 %ret = call i8* @memchr(i8* %ptr, i32 %C, i64 7) ret i8* %ret } ; Don't fold memchr(a1110111, C, N). define i8* @call_memchr_a1110111_c_n(i32 %C, i64 %N) { ; CHECK-LABEL: @call_memchr_a1110111_c_n( ; CHECK-NEXT: [[RET:%.*]] = call i8* @memchr(i8* getelementptr inbounds ([7 x i8], [7 x i8]* @a1110111, i64 0, i64 0), i32 [[C:%.*]], i64 [[N:%.*]]) ; CHECK-NEXT: ret i8* [[RET]] ; %ptr = getelementptr [7 x i8], [7 x i8]* @a1110111, i64 0, i64 0 %ret = call i8* @memchr(i8* %ptr, i32 %C, i64 %N) ret i8* %ret }