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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --function-signature
; RUN: opt -inline -S < %s | FileCheck --check-prefixes=CHECK,NO_ASSUME %s
; RUN: opt -inline -S --enable-knowledge-retention < %s | FileCheck %s --check-prefixes=CHECK,USE_ASSUME
; The callee guarantees that the pointer argument is nonnull and dereferenceable.
; That information should transfer to the caller.
define i32 @callee(i32* dereferenceable(32) %t1) {
; CHECK-LABEL: define {{[^@]+}}@callee
; CHECK-SAME: (i32* dereferenceable(32) [[T1:%.*]]) {
; CHECK-NEXT: [[T2:%.*]] = load i32, i32* [[T1]], align 4
; CHECK-NEXT: ret i32 [[T2]]
;
%t2 = load i32, i32* %t1
ret i32 %t2
}
define i32 @callee2(i32* dereferenceable(32) %t1, i32 noundef %t2) {
; CHECK-LABEL: define {{[^@]+}}@callee2
; CHECK-SAME: (i32* dereferenceable(32) [[T1:%.*]], i32 noundef [[T2:%.*]]) {
; CHECK-NEXT: [[V:%.*]] = load i32, i32* [[T1]], align 4
; CHECK-NEXT: ret i32 [[V]]
;
%v = load i32, i32* %t1
ret i32 %v
}
; FIXME: All dereferenceability information is lost.
; The caller argument could be known nonnull and dereferenceable(32).
define i32 @caller1(i32* %t1, i32 %t2) {
; NO_ASSUME-LABEL: define {{[^@]+}}@caller1
; NO_ASSUME-SAME: (i32* [[T1:%.*]], i32 [[T2:%.*]]) {
; NO_ASSUME-NEXT: [[V_I:%.*]] = load i32, i32* [[T1]], align 4
; NO_ASSUME-NEXT: ret i32 [[V_I]]
;
; USE_ASSUME-LABEL: define {{[^@]+}}@caller1
; USE_ASSUME-SAME: (i32* [[T1:%.*]], i32 [[T2:%.*]]) {
; USE_ASSUME-NEXT: call void @llvm.assume(i1 true) [ "dereferenceable"(i32* [[T1]], i64 32), "noundef"(i32 [[T2]]) ]
; USE_ASSUME-NEXT: [[V_I:%.*]] = load i32, i32* [[T1]], align 4
; USE_ASSUME-NEXT: ret i32 [[V_I]]
;
%v = tail call i32 @callee2(i32* dereferenceable(32) %t1, i32 noundef %t2)
ret i32 %v
}
; The caller argument is nonnull, but that can be explicit.
; The dereferenceable amount could be increased.
define i32 @caller2(i32* dereferenceable(31) %t1) {
; NO_ASSUME-LABEL: define {{[^@]+}}@caller2
; NO_ASSUME-SAME: (i32* dereferenceable(31) [[T1:%.*]])
; NO_ASSUME-NEXT: [[T2_I:%.*]] = load i32, i32* [[T1]]
; NO_ASSUME-NEXT: ret i32 [[T2_I]]
;
; USE_ASSUME-LABEL: define {{[^@]+}}@caller2
; USE_ASSUME-SAME: (i32* dereferenceable(31) [[T1:%.*]])
; USE_ASSUME-NEXT: call void @llvm.assume(i1 true) [ "dereferenceable"(i32* [[T1]], i64 32) ]
; USE_ASSUME-NEXT: [[T2_I:%.*]] = load i32, i32* [[T1]]
; USE_ASSUME-NEXT: ret i32 [[T2_I]]
;
%t2 = tail call i32 @callee(i32* dereferenceable(32) %t1)
ret i32 %t2
}
; The caller argument is nonnull, but that can be explicit.
; Make sure that we don't propagate a smaller dereferenceable amount.
define i32 @caller3(i32* dereferenceable(33) %t1) {
; CHECK-LABEL: define {{[^@]+}}@caller3
; CHECK-SAME: (i32* dereferenceable(33) [[T1:%.*]])
; CHECK-NEXT: [[T2_I:%.*]] = load i32, i32* [[T1]]
; CHECK-NEXT: ret i32 [[T2_I]]
;
%t2 = tail call i32 @callee(i32* dereferenceable(32) %t1)
ret i32 %t2
}
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