Summary:
For `__builtin_assume_aligned()`, we do validate that the alignment
is not greater than `
536870912` (D68824), but we don't do that for
`__attribute__((assume_aligned(N)))` attribute.
I suspect we should.
Reviewers: erichkeane, aaron.ballman, hfinkel, rsmith, jdoerfert
Reviewed By: erichkeane
Subscribers: cfe-commits, llvm-commits
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D72994
<< E->getSourceRange();
return;
}
+
+ // Alignment calculations can wrap around if it's greater than 2**29.
+ unsigned MaximumAlignment = 536870912;
+ if (I > MaximumAlignment)
+ Diag(CI.getLoc(), diag::warn_assume_aligned_too_great)
+ << CI.getRange() << MaximumAlignment;
}
if (OE) {
void test_void_assume_aligned(void) __attribute__((assume_aligned(32))); // expected-warning {{'assume_aligned' attribute only applies to return values that are pointers}}
int test_int_assume_aligned(void) __attribute__((assume_aligned(16))); // expected-warning {{'assume_aligned' attribute only applies to return values that are pointers}}
void *test_ptr_assume_aligned(void) __attribute__((assume_aligned(64))); // no-warning
+void *test_ptr_assume_aligned(void) __attribute__((assume_aligned(1073741824))); // expected-warning {{requested alignment must be 536870912 bytes or smaller; maximum alignment assumed}}
int j __attribute__((assume_aligned(8))); // expected-warning {{'assume_aligned' attribute only applies to Objective-C methods and functions}}
void *test_no_fn_proto() __attribute__((assume_aligned(32))); // no-warning