This makes use of the recently-added @llvm.assume intrinsic to implement a
__builtin_assume(bool) intrinsic (to provide additional information to the
optimizer). This hooks up __assume in MS-compatibility mode to mirror
__builtin_assume (the semantics have been intentionally kept compatible), and
implements GCC's __builtin_assume_aligned as assume((p - o) & mask == 0). LLVM
now contains special logic to deal with assumptions of this form.
llvm-svn: 217349
the no-arguments case. Don't expand this to an __attribute__((nonnull(A, B,
C))) attribute, since that does the wrong thing for function templates and
varargs functions.
In passing, fix a grammar error in the diagnostic, a crash if
__attribute__((nonnull(N))) is applied to a varargs function,
a bug where the same null argument could be diagnosed multiple
times if there were multiple nonnull attributes referring to it,
and a bug where nonnull attributes would not be accumulated correctly
across redeclarations.
llvm-svn: 216520
macro arguments.
Previously, these warnings skipped any code in a macro expansion. Preform an
additional check and warn when the expression and context locations are both
in the macro argument.
The most obvious case not caught is passing a pointer directly to a macro,
i.e 'assert(&array)' but 'assert(&array && "valid array")' is caught. This is
because macro arguments are not typed and the conversion happens inside the
macro.
llvm-svn: 215251
question mark instead of the context of the conditional operator. The
condition does not need the context of the conditional operator at all.
llvm-svn: 215048
The main subtlety here is that the Darwin tools still need to be given "-arch
arm64" rather than "-arch aarch64". Fortunately this already goes via a custom
function to handle weird edge-cases in other architectures, and it tested.
I removed a few arm64_be tests because that really isn't an interesting thing
to worry about. No-one using big-endian is also referring to the target as
arm64 (at least as far as toolchains go). Mostly they date from when arm64 was
a separate target and we *did* need a parallel name simply to test it at all.
Now aarch64_be is sufficient.
llvm-svn: 213744
Windows ARM indicates __va_start as a variadic function. However, the function
itself is treated as having 4 formal arguments:
- (out) pointer to the va_list
- (in) address of the last named argument
- (in) slot size for the type of the last argument
- address of the last named argument
The last argument does not seem to have any bearing on codegen, and thus is not
explicitly type checked at this point.
Unlike the previous handling for __va_start, it does not currently validate if
the parameter is the last named parameter (it seems that MSVC currently accepts
this).
llvm-svn: 213595
This fixes a couple of asserts when analyzing comparisons involving
C11 atomics that were uncovered by r205608 when we extended the
applicability of -Wtautological-constant-out-of-range-compare.
llvm-svn: 213573
In MS-compatibility mode, we support the __assume builtin. The __assume builtin
does not evaluate its arguments, and we should issue a warning if __assume is
provided with an argument with side effects (because these effects will be
discarded).
This is similar in spirit to the warnings issued by other compilers (Intel
Diagnostic 2261, MS Compiler Warning C4557).
llvm-svn: 213266
Memory barrier __builtin_arm_[dmb, dsb, isb] intrinsics are required to
implement their corresponding ACLE and MSVC intrinsics.
This patch ports ARM dmb, dsb, isb intrinsic to AArch64.
Requires LLVM r213247.
Differential Revision: http://reviews.llvm.org/D4521
llvm-svn: 213250
ARMv8 adds (to both AArch32 and AArch64) acquiring and releasing
variants of the exclusive operations, in line with the C++11 memory
model.
This adds support for two new intrinsics to expose them to C & C++
developers directly: __builtin_arm_ldaex and __builtin_arm_stlex, in
direct analogy with the versions with no implicit barrier.
rdar://problem/15885451
llvm-svn: 212175
Fixes PR20110, where Clang hits an assertion failure when it expects that the
sub-expression of a bit cast to pointer to also be a pointer, but gets a value
instead.
Differential Revision: http://reviews.llvm.org/D4280
llvm-svn: 212160
The compilation pipeline doesn't actually need to know about the high-level
concept of diagnostic mappings, and hiding the final computed level presents
several simplifications and other potential benefits.
The only exceptions are opportunistic checks to see whether expensive code
paths can be avoided for diagnostics that are guaranteed to be ignored at a
certain SourceLocation.
This commit formalizes that invariant by introducing and using
DiagnosticsEngine::isIgnored() in place of individual level checks throughout
lex, parse and sema.
llvm-svn: 211005
to call themselves will get the warning:
"Capturing <itself> strongly in this block is likely to
lead to a retain cycle". Cut down on the amount of noise
by noticing that user at some point sets the captured variable
to null in order to release it (and break the cycle).
// rdar://16944538
llvm-svn: 210823
will never be true in a well-defined context. The checking for null pointers
has been moved into the caller logic so it does not rely on undefined behavior.
llvm-svn: 210498
to the normal non-placement ::operator new and ::operator delete, but allow
optimizations like new-expressions and delete-expressions do.
llvm-svn: 210137
This allows us to be more careful when dealing with enums whose fixed
underlying type requires special handling in a format string, like
NSInteger.
A refinement of r163266 from a year and a half ago, which added the
special handling for NSInteger and friends in the first place.
<rdar://problem/16616623>
llvm-svn: 209966
A few (mostly CodeGen) parts of Clang were tightly coupled to the
AArch64 backend. Now that it's gone, they will not even compile.
I've also deduplicated RUN lines in many of the AArch64 tests. This
might improve "make check-all" time noticably: some of those NEON
tests were monsters.
llvm-svn: 209578
The conventional form is '<action> to silence this warning'.
Also call the diagnostic an 'issue' rather than a 'message' because the latter
term is more widely used with reference to message expressions.
llvm-svn: 209052
Warn on std::abs() with unsigned argument.
Suggest std::abs as replacement for the C absolute value functions.
Suggest C++ headers if the specific std::abs overload is not found.
llvm-svn: 206340
better. This warning will now trigger on the following conditionals:
bool b;
int i;
if (b > 1) {} // always false
if (0 <= (i > 5)) {} // always true
if (-1 > b) {} // always false
Patch by Per Viberg.
llvm-svn: 205608
This adds Clang support for the ARM64 backend. There are definitely
still some rough edges, so please bring up any issues you see with
this patch.
As with the LLVM commit though, we think it'll be more useful for
merging with AArch64 from within the tree.
llvm-svn: 205100
The main difference between __va_start and __builtin_va_start is that
the address of the va_list has already been taken, and the va_list is
always a char*.
__va_end and __va_arg are not needed.
llvm-svn: 204821
Someone could write:
if (0) {
__c11_atomic_load(ptr, memory_order_release);
}
or the equivalent, which is perfectly valid, so we shouldn't outright reject
invalid orderings on purely static grounds.
rdar://problem/16242991
llvm-svn: 203564
This is a conservative check, because it's valid for the expression to be
non-constant, and in cases like that we just don't know whether it's valid.
rdar://problem/16242991
llvm-svn: 203561
const char *format = "%s";
std::experimental::string_view view = "foo";
printf(format, view);
In this case, not only warn about a class type being used here, but also suggest that calling c_str() might be a good idea.
llvm-svn: 202461
null comparison when the pointer is known to be non-null.
This catches the array to pointer decay, function to pointer decay and
address of variables. This does not catch address of function since this
has been previously used to silence a warning.
Pointer to bool conversion is under -Wbool-conversion.
Pointer to null comparison is under -Wtautological-pointer-compare, a sub-group
of -Wtautological-compare.
void foo() {
int arr[5];
int x;
// warn on these conditionals
if (foo);
if (arr);
if (&x);
if (foo == null);
if (arr == null);
if (&x == null);
if (&foo); // no warning
}
llvm-svn: 202216
The warnings fall into three groups.
1) Using an absolute value function of the wrong type, for instance, using the
int absolute value function when the argument is a floating point type.
2) Using the improper sized absolute value function, for instance, using abs
when the argument is a long long. llabs should be used instead.
From these two cases, an implicit conversion will occur which may cause
unexpected behavior. Where possible, suggest the proper absolute value
function to use, and which header to include if the function is not available.
3) Taking the absolute value of an unsigned value. In addition to this warning,
suggest to remove the function call. This usually indicates a logic error
since the programmer assumed negative values would have been possible.
llvm-svn: 202211
Most 64-bit targets define int64_t as long int, and AArch64 should
make same definition to follow LP64 model. In GNU tool chain, int64_t
is defined as long int for 64-bit target. So to get consistent with GNU,
it's better Changing int64_t from 'long long int' to 'long int',
otherwise clang will get different name mangling suffix compared with g++.
llvm-svn: 202004
Because GCC incorrectly defines _mm_prefetch to take anything that casts
to void*, people have started using that behavior. The previous patch
that made _mm_prefetch actually take a const char * broke compatibility
with existing code. This update to the patch leaves the macro that
defines _mm_prefetch with the (void*) cast when _MSC_VER is not defined.
llvm-svn: 201901
This breaks backwards compatibility with existing code. Previously, this
was defined as
#define _mm_prefetch(a, sel) (__builtin_prefetch((void *)(a), 0, (sel)))
Which basically accepts any pointer. Changing this to char* simply
breaks a lot of existing code. I have tried changing char* to
"const void*", which seems to be the right thing as per Intel
specification this should work on basically any pointer. However,
apparently this breaks windows compatibility (because of a conflicting
declaration in windows.h).
So, we probably need to #ifdef this based on whether clang is compiling
for windows. According to Chandler, this might be done by introducing an
additional symbol to a fake type in BuiltinsX86.def and then condition
the type expansion on the platform.
llvm-svn: 201775
This patch adds several built-ins that are required for ms
compatibility. _mm_prefetch must be a built-in because it takes a
compile-time constant argument and our prior approach of using a #define
to the current built-in doesn't work in the presence of re-declaration
of _mm_prefetch. The others can be obtained by including the windows
system headers. If a user includes the windows system headers but not
intrin.h they still need to work and therefore must be built-in because
we don't get a chance to implement them in intrin.h in this case.
llvm-svn: 201734
There are two kinds of automatically generated tests for NEON intrinsics, both
of which can be merged without adversely affecting users.
1. We check that a valid kind of __builtin_neon_XYZ overload is requested (e.g.
we're not asking for a float32x4_t version when it only accepts integers. Since
the __builtin_neon_XYZ intrinsics should only be used in arm_neon.h, relaxing
this test and permitting AArch64 types for AArch32 should not cause a problem.
The extra arm_neon.h definitions should be #ifdefed out anyway.
2. We check that intrinsics which take immediates are actually given
compile-time constants within range. Since all NEON intrinsics should be
backwards compatible, these tests should be identical on AArch64 and AArch32
anyway.
This patch, therefore, merges the separate AArch64 and 32-bit checks.
rdar://problem/16035743
llvm-svn: 201659
Previously, range checking on the __builtin_neon_XYZ_v Clang intrinsics didn't
take account of the type actually passed to the call, which meant a request
like "vext_s16(a, b, 7)" was allowed through (TableGen was conservative and
allowed 0-7 for all types). This caused an assert in the backend because the
lane doesn't make sense.
llvm-svn: 201232
A return type is the declared or deduced part of the function type specified in
the declaration.
A result type is the (potentially adjusted) type of the value of an expression
that calls the function.
Rule of thumb:
* Declarations have return types and parameters.
* Expressions have result types and arguments.
llvm-svn: 200082
Previously, string literals were ignored in all logical expressions. This
reduces it to only ignore in logical and expressions.
assert(0 && "error"); // No warning
assert(0 || "error"); // Warn
Fixes PR17565
llvm-svn: 200056
This involved making CheckReturnStackAddr into a static function, which
is now called by a top-level return value checking routine called
CheckReturnValExpr.
llvm-svn: 199790
Fix a perennial source of confusion in the clang type system: Declarations and
function prototypes have parameters to which arguments are supplied, so calling
these 'arguments' was a stretch even in C mode, let alone C++ where default
arguments, templates and overloading make the distinction important to get
right.
Readability win across the board, especially in the casting, ADL and
overloading implementations which make a lot more sense at a glance now.
Will keep an eye on the builders and update dependent projects shortly.
No functional change.
llvm-svn: 199686
This allows the following syntax:
void baz(__attribute__((nonnull)) const char *str);
instead of:
void baz(const char *str) __attribute__((nonnull(1)));
This also extends to Objective-C methods.
The checking logic in Sema is not as clean as I would like. Effectively
now we need to check both the FunctionDecl/ObjCMethodDecl and the parameters,
so the point of truth is spread in two places, but the logic isn't that
cumbersome.
Implements <rdar://problem/14691443>.
llvm-svn: 199467
The ABI requires the destructor to be invoked in the callee, but the
standard does not require access checks here so we avoid doing direct
access checks on the destructor.
If we end up needing to define an implicit destructor, we don't skip
access checks for the base class, etc. Those checks are effectively part
of generating the destructor definition, and aren't affected by which TU
the check is performed in.
Differential Revision: http://llvm-reviews.chandlerc.com/D2409
llvm-svn: 199120
encodes the canonical rules for LLVM's style. I noticed this had drifted
quite a bit when cleaning up LLVM, so wanted to clean up Clang as well.
llvm-svn: 198686
Thisadds a new warning that warns on code like this:
if (memcmp(a, b, sizeof(a) != 0))
The warning looks like:
test4.cc:5:30: warning: size argument in 'memcmp' call is a comparison [-Wmemsize-comparison]
if (memcmp(a, b, sizeof(a) != 0))
~~~~~~~~~~^~~~
test4.cc:5:7: note: did you mean to compare the result of 'memcmp' instead?
if (memcmp(a, b, sizeof(a) != 0))
^ ~
)
test4.cc:5:20: note: explicitly cast the argument to size_t to silence this warning
if (memcmp(a, b, sizeof(a) != 0))
^
(size_t)( )
1 warning generated.
This found 2 bugs in chromium and has 0 false positives on both chromium and
llvm.
The idea of triggering this warning on a binop in the size argument is due to
rnk.
llvm-svn: 198063
Summary:
MSVC destroys arguments in the callee from left to right. Because C++
objects have to be destroyed in the reverse order of construction, Clang
has to construct arguments from right to left and destroy arguments from
left to right.
This patch fixes the ordering by reversing the order of evaluation of
all call arguments under the MS C++ ABI.
Fixes PR18035.
Reviewers: rsmith
Differential Revision: http://llvm-reviews.chandlerc.com/D2275
llvm-svn: 196402
The AST was constructed so that this builtin returned the default BoolTy and
since I'd opted for custom SemaChecking, I should have set it properly at that
point.
This caused an assertion failure when the types didn't match up with what we
generated. This makes it return an IntTy, which is as good as anything.
llvm-svn: 193606
