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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; Verify that strnlen calls with conditional expressions involving constant
; string arguments with nonconstant bounds are folded correctly.
;
; RUN: opt < %s -passes=instcombine -S | FileCheck %s
declare i64 @strnlen(ptr, i64)
@sx = external global [0 x i8]
@s3 = constant [4 x i8] c"123\00"
@s5 = constant [6 x i8] c"12345\00"
@s5_3 = constant [10 x i8] c"12345\00abc\00"
; Fold strnlen (C ? s3 + i : s5, %n) to min(C ? 3 : 5, i) when
; s3 + i is guaranteed to be within the bounds of s3.
define i64 @fold_strnlen_s3_pi_s5_n(i1 %C, i64 %i, i64 %n) {
; CHECK-LABEL: @fold_strnlen_s3_pi_s5_n(
; CHECK-NEXT: [[PTR:%.*]] = getelementptr inbounds [4 x i8], ptr @s3, i64 0, i64 [[I:%.*]]
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C:%.*]], ptr [[PTR]], ptr @s5
; CHECK-NEXT: [[LEN:%.*]] = call i64 @strnlen(ptr nonnull [[SEL]], i64 [[N:%.*]])
; CHECK-NEXT: ret i64 [[LEN]]
;
%ptr = getelementptr inbounds [4 x i8], ptr @s3, i64 0, i64 %i
%sel = select i1 %C, ptr %ptr, ptr @s5
%len = call i64 @strnlen(ptr %sel, i64 %n)
ret i64 %len
}
; Do not fold the same expression as above when s3 + i is not guaranteed
; to be within the bounds of s3. Also verify that the call is not marked
; noundef, nonnull, or dereferenceable because a zero bound implies no
; access.
define i64 @call_strnlen_s3_pi_xbounds_s5_n(i1 %C, i64 %i, i64 %n) {
; CHECK-LABEL: @call_strnlen_s3_pi_xbounds_s5_n(
; CHECK-NEXT: [[PTR:%.*]] = getelementptr [4 x i8], ptr @s3, i64 0, i64 [[I:%.*]]
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C:%.*]], ptr [[PTR]], ptr @s5
; CHECK-NEXT: [[LEN:%.*]] = call i64 @strnlen(ptr [[SEL]], i64 [[N:%.*]])
; CHECK-NEXT: ret i64 [[LEN]]
;
%ptr = getelementptr [4 x i8], ptr @s3, i64 0, i64 %i
%sel = select i1 %C, ptr %ptr, ptr @s5
%len = call i64 @strnlen(ptr %sel, i64 %n)
ret i64 %len
}
; Do not fold strnlen(C ? s3 + i : sx, n) when sx's length and size
; are unknown. This also verifies that the folder cleans up the IR after
; successfully folding the first subexpression IR when folding the second
; subexpression fails.
define i64 @call_strnlen_s3_pi_sx_n(i1 %C, i64 %i, i64 %n) {
; CHECK-LABEL: @call_strnlen_s3_pi_sx_n(
; CHECK-NEXT: [[PTR:%.*]] = getelementptr inbounds [4 x i8], ptr @s3, i64 0, i64 [[I:%.*]]
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C:%.*]], ptr [[PTR]], ptr @sx
; CHECK-NEXT: [[LEN:%.*]] = call i64 @strnlen(ptr nonnull [[SEL]], i64 [[N:%.*]])
; CHECK-NEXT: ret i64 [[LEN]]
;
%ptr = getelementptr inbounds [4 x i8], ptr @s3, i64 0, i64 %i
%sel = select i1 %C, ptr %ptr, ptr @sx
%len = call i64 @strnlen(ptr %sel, i64 %n)
ret i64 %len
}
; Fold strnlen (C ? s3 : s5 + i, n) to min(C ? 3 : 5, i).
define i64 @fold_strnlen_s3_s5_pi_n(i1 %C, i64 %i, i64 %n) {
; CHECK-LABEL: @fold_strnlen_s3_s5_pi_n(
; CHECK-NEXT: [[PTR:%.*]] = select i1 [[C:%.*]], ptr @s5, ptr @s3
; CHECK-NEXT: [[LEN:%.*]] = call i64 @strnlen(ptr nonnull [[PTR]], i64 [[I:%.*]])
; CHECK-NEXT: ret i64 [[LEN]]
;
%ptr = select i1 %C, ptr @s5, ptr @s3
%len = call i64 @strnlen(ptr %ptr, i64 %i)
ret i64 %len
}
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