In atomic builtins, we assumed that the LValue conversion on the first
argument would succeed. So, we would crash given code like:
```
void ovl(char);
void ovl(int);
__atomic_store_n(ovl, 0, 0);
```
This patch makes us not assume that said conversion is successful. :)
llvm-svn: 276232
This patch implements PR#22821.
Taking the address of a packed member is dangerous since the reduced
alignment of the pointee is lost. This can lead to memory alignment
faults in some architectures if the pointer value is dereferenced.
This change adds a new warning to clang emitted when taking the address
of a packed member. A packed member is either a field/data member
declared as attribute((packed)) or belonging to a struct/class
declared as such. The associated flag is -Waddress-of-packed-member.
Conversions (either implicit or via a valid casting) to pointer types
with lower or equal alignment requirements (e.g. void* or char*)
silence the warning.
This change also adds a new error diagnostic when the user attempts to
bind a reference to a packed member, regardless of the alignment.
Differential Revision: https://reviews.llvm.org/D20561
llvm-svn: 275417
- Added new Builtins: enqueue_kernel, get_kernel_work_group_size
and get_kernel_preferred_work_group_size_multiple.
These Builtins use custom check to diagnose parameters of the passed Blocks
i. e. variable number of 'local void*' type params, and check different
overloads specified in Table 6.31 of OpenCL v2.0.
- IR is generated as an internal library call for each OpenCL Builtin,
reusing ObjC Block implementation.
Review: http://reviews.llvm.org/D20249
llvm-svn: 274540
Currently we only have OpenCL 2.0 Builtins i.e. pipes or address space conversions.
They have to be added only in the version 2.0 compilation mode to make the identifiers
available for use in the other versions.
Review: http://reviews.llvm.org/D20249
llvm-svn: 274509
OpenCL builtin functions to_{global|local|private} accepts argument of pointer type to arbitrary pointee type, and return a pointer to the same pointee type in different addr space, i.e.
global gentype *to_global(gentype *p);
It is not desirable to declare it as
global void *to_global(void *);
in opencl header file since it misses diagnostics.
This patch implements these builtin functions as Clang builtin functions. In the builtin def file they are defined to have signature void*(void*). When handling call expressions, their declarations are re-written to have correct parameter type and return type corresponding to the call argument.
In codegen call to addr void *to_addr(void*) is generated with addrcasts or bitcasts to facilitate implementation in builtin library.
Differential Revision: http://reviews.llvm.org/D19932
llvm-svn: 270261
I couldn't find any documentation that this form existed either. Nor is there documentation for one of the remaining two forms, but there is a testcase that uses it.
llvm-svn: 269879
Remove the floating point to bool conversion warnings. Some of these
conversions will be caught by -Wliteral-conversion and -Wfloat-conversion
llvm-svn: 267234
Restructure the implict floating point to integer conversions so that
interesting sub-groups are under different flags. Breakdown of warnings:
No warning:
Exact conversions from floating point to integer:
int x = 10.0;
int x = 1e10;
-Wliteral-conversion - Floating point literal to integer with rounding:
int x = 5.5;
int x = -3.4;
-Wfloat-conversion - All conversions not covered by the above two:
int x = GetFloat();
int x = 5.5 + 3.5;
-Wfloat-zero-conversion - The expression converted has a non-zero floating
point value that gets converted to a zero integer value, excluded the cases
falling under -Wliteral-conversion. Subset of -Wfloat-conversion.
int x = 1.0 / 2.0;
-Wfloat-overflow-conversion - The floating point value is outside the range
of the integer type, exluding cases from -Wliteral conversion. Subset of
-Wfloat-conversion.
char x = 500;
char x = -1000;
-Wfloat-bool-conversion - Any conversion of a floating point type to bool.
Subset of -Wfloat-conversion.
if (GetFloat()) {}
bool x = 5.0;
-Wfloat-bool-constant-conversion - Conversion of a compile time evaluatable
floating point value to bool. Subset of -Wfloat-bool-conversion.
bool x = 1.0;
bool x = 4.0 / 20.0;
Also add EvaluateAsFloat to Sema, which is similar to EvaluateAsInt, but for
floating point values.
llvm-svn: 267054
Although all the registers are actually 32-bits, I think we have to assume the
high 32-bits could be RES0 (the ARM ARM is unclear). If so, reading as a 32-bit
register can require extra zero extension operations.
llvm-svn: 266212
This warning sometimes will infinitely recurse on CXXRecordDecl's from
ill-formed recursive classes that have fields of themselves. Skip processing
these classes to prevent this from happening.
Fixes https://llvm.org/bugs/show_bug.cgi?id=27142
llvm-svn: 264991
Summary:
__atomic_load's allows it's first argument to be a pointer to a const type. However the second argument is an output parameter and must be a pointer to non-const.
This patch fixes the signature of __atomic_load generated by clang so that it respects the above requirements.
Reviewers: rsmith, majnemer
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D13420
llvm-svn: 264967
Summary:
1. Diag should be output if types are not the same.
2. Should compare using canonical type.
3. Refine the diag to be more clear.
Reviewers: yaxunl, Anastasia
Subscribers: MatsPetersson, pekka.jaaskelainen, cfe-commits
Differential Revision: http://reviews.llvm.org/D17955
llvm-svn: 264825
r263299 added a fixit for the -Wformat-security warning, but that runs
into complications with our guideline that error recovery should be done
as-if the fixit had been applied. Putting the fixit on a note avoids that.
llvm-svn: 263584
Summary:
The printf/scanf format checker is a little over-zealous in handling the conditional operator. This patch reduces work by not checking code-paths that are never used and reduces false positives regarding uncovered arguments, for example in the code fragment:
printf(minimal ? "%i\n" : "%i: %s\n", code, msg);
Reviewers: rtrieu
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D15636
llvm-svn: 262025
Summary:
OpenCL access qualifiers are now not only used for image types, refine it to avoid misleading,
Add semacheck for OpenCL access qualifier as well as test caees.
Reviewers: pekka.jaaskelainen, Anastasia, aaron.ballman
Subscribers: aaron.ballman, cfe-commits
Differential Revision: http://reviews.llvm.org/D16040
llvm-svn: 261961
In the case that the array indexing itself is within a type dependent context,
bail out of the evaluation. We would previously try to symbolically evaluate
the expression which would then try to evaluate a non-address expression as an
address, triggering an assertion in Asserts builds.
We only need to consider the array subscript expression itself as in the case
that the base itself being type dependent is handled appropriately in EvalAddr.
Resolves PR26599.
llvm-svn: 260867
When a null constant is used in a macro, walk through the macro stack to
determine where the null constant is written and where the context is located.
Only warn if both locations are within the same macro expansion. This helps
function-like macros which involve pointers be treated as if they were
functions.
llvm-svn: 260776
r257357 fixed clang to warn on integer overflow in struct initializers.
However, it didn't warn when a struct had a nested initializer. This
commit makes changes in Sema::CheckForIntOverflow to handle nested
initializers.
For example:
struct s {
struct t {
unsigned x;
} t;
} s = {
{
.x = 4 * 1024 * 1024 * 1024
}
};
rdar://problem/23526454
llvm-svn: 260360
Sometimes, char arrays are used as bit storage, with no difference made between
signed and unsigned char. Thus, it is reasonable to use 0 to 255 instead of
-128 to 127 and not trigger this warning.
llvm-svn: 259947
Switch the evaluation from isIntegerConstantExpr to EvaluateAsInt.
EvaluateAsInt will evaluate more types of expressions than
isIntegerConstantExpr.
Move one case from -Wsign-conversion to -Wconstant-conversion. The case is:
1) Source and target types are signed
2) Source type is wider than the target type
3) The source constant value is positive
4) The conversion will store the value as negative in the target.
llvm-svn: 259271
Fix arc patch fuzz error.
Summary:
Support for the pipe built-in functions for OpenCL 2.0.
The pipe builtin functions may have infinite kinds of element types, one approach
would be to just generate calls that would always use generic types such as void*.
This patch is based on bader's opencl support patch on SPIR-V branch.
Reviewers: Anastasia, pekka.jaaskelainen
Subscribers: keryell, bader, cfe-commits
Differential Revision: http://reviews.llvm.org/D15914
llvm-svn: 258782
Move the function to get a macro name from DiagnosticRenderer.cpp to Lexer.cpp
so that other files can use it. Lexer now has two functions to get the
immediate macro name, the newly added one is better for diagnostic purposes.
Make -Wnull-conversion use this function for better NULL macro detection.
llvm-svn: 258778
Summary:
Support for the pipe built-in functions for OpenCL 2.0.
The pipe builtin functions may have infinite kinds of element types, one approach
would be to just generate calls that would always use generic types such as void*.
This patch is based on bader's opencl support patch on SPIR-V branch.
Reviewers: Anastasia, pekka.jaaskelainen
Subscribers: keryell, bader, cfe-commits
Differential Revision: http://reviews.llvm.org/D15914
llvm-svn: 258773
In {CG,}ExprConstant.cpp, we weren't treating vector splats properly.
This patch makes us treat splats more properly.
Additionally, this patch adds a new cast kind which allows a bool->int
cast to result in -1 or 0, instead of 1 or 0 (for true and false,
respectively), so we can sanely model OpenCL bool->int casts in the AST.
Differential Revision: http://reviews.llvm.org/D14877
llvm-svn: 257559
-Wnull-conversion warning.
These functions are basically equivalent to other pointer returning fuctions
which are already excluded by -Wnull-conversion.
llvm-svn: 257231
If there are two pointers passed to an atomic Builtin,
Clang doesn't allow the second (non-atomic) one to be qualified
with an address space.
Remove this restriction by recording the address space of passed pointers
in atomics type diagnostics.
llvm-svn: 256243
Currently, we emit warnings in some cases where nonnull function
parameters are compared against null. This patch extends this support
to warn when comparing the result of `returns_nonnull` functions
against null.
More specifically, we will now warn cases like:
int *foo() __attribute__((returns_nonnull));
int main() {
if (foo() == NULL) {} // warning: will always evaluate to false
}
Differential Revision: http://reviews.llvm.org/D15324
llvm-svn: 255058
side-effect, so that we don't allow speculative evaluation of such expressions
during code generation.
This caused a diagnostic quality regression, so fix constant expression
diagnostics to prefer either the first "can't be constant folded" diagnostic or
the first "not a constant expression" diagnostic depending on the kind of
evaluation we're doing. This was always the intent, but didn't quite work
correctly before.
This results in certain initializers that used to be constant initializers to
no longer be; in particular, things like:
float f = 1e100;
are no longer accepted in C. This seems appropriate, as such constructs would
lead to code being executed if sanitizers are enabled.
llvm-svn: 254574
`pass_object_size` is our way of enabling `__builtin_object_size` to
produce high quality results without requiring inlining to happen
everywhere.
A link to the design doc for this attribute is available at the
Differential review link below.
Differential Revision: http://reviews.llvm.org/D13263
llvm-svn: 254554
Clang tries to figure out if a call to abs is suspicious by looking
through implicit casts to look at the underlying, implicitly converted
type.
Interestingly, C has implicit conversions from pointer-ish types like
function to less exciting types like int. This trips up our 'abs'
checker because it doesn't know which variant of 'abs' is appropriate.
Instead, diagnose 'abs' called on function types upfront. This sort of
thing is highly suspicious and is likely indicative of a missing
pointer dereference/function call/array index operation.
This fixes PR25532.
llvm-svn: 253156
GCC has a warning called -Wdouble-promotion, which warns you when
an implicit conversion increases the width of a floating point type.
This is useful when writing code for architectures that can perform
hardware FP ops on floats, but must fall back to software emulation for
larger types (i.e. double, long double).
This fixes PR15109 <https://llvm.org/bugs/show_bug.cgi?id=15109>.
Thanks to Carl Norum for the patch!
llvm-svn: 251588
Summary:
Currently when a function annotated with __attribute__((nonnull)) is called in an unevaluated context with a null argument a -Wnonnull warning is emitted.
This warning seems like a false positive unless the call expression is potentially evaluated. Change this behavior so that the non-null warnings use DiagRuntimeBehavior so they wont emit when they won't be evaluated.
Reviewers: majnemer, rsmith
Subscribers: mclow.lists, cfe-commits
Differential Revision: http://reviews.llvm.org/D13408
llvm-svn: 249787
Diagnose when a pointer to const T is used as the first argument in at atomic
builtin unless that builtin is a load operation. This is already checked for
C11 atomics builtins but not for __atomic ones.
This patch was given the LGTM by rsmith when it was part
of a larger review. (See http://reviews.llvm.org/D10407)
llvm-svn: 249252
The changes are part of attribute-based CUDA function overloading (D12453)
and as such are only enabled when it's in effect (-fcuda-target-overloads).
Differential Revision: http://reviews.llvm.org/D12122
llvm-svn: 248296
Summary:
This change adds support for `__builtin_ms_va_list`, a GCC extension for
variadic `ms_abi` functions. The existing `__builtin_va_list` support is
inadequate for this because `va_list` is defined differently in the Win64
ABI vs. the System V/AMD64 ABI.
Depends on D1622.
Reviewers: rsmith, rnk, rjmccall
CC: cfe-commits
Differential Revision: http://reviews.llvm.org/D1623
llvm-svn: 247941
Summary:
Currently clang provides no general way to generate nontemporal loads/stores.
There are some architecture specific builtins for doing so (e.g. in x86), but
there is no way to generate non-temporal store on, e.g. AArch64. This patch adds
generic builtins which are expanded to a simple store with '!nontemporal'
attribute in IR.
Differential Revision: http://reviews.llvm.org/D12313
llvm-svn: 247104
Adds parsing/sema analysis/serialization/deserialization for array sections in OpenMP constructs (introduced in OpenMP 4.0).
Currently it is allowed to use array sections only in OpenMP clauses that accepts list of expressions.
Differential Revision: http://reviews.llvm.org/D10732
llvm-svn: 245937
Objective-C collection literals produce unspecialized
NSArray/NSDictionary objects that can then be implicitly converted to
specialized versions of these types. In such cases, check that the
elements in the collection are suitable for the specialized
collection. Part of rdar://problem/6294649.
llvm-svn: 241546
Objective-C format strings now support modifier flags
that can be attached to a '@' conversion. Currently
the only one supported, as of iOS 9 and OS X 10.11,
is the new "technical term", denoted by the flag "tt",
for example:
%[tt]@
instead of just:
%@
The 'tt' stands for "technical term", which is used
by the string-localization facilities on Darwin to
add the appropriate spacing or quotation depending
the language locale.
Implements <rdar://problem/20374720>.
llvm-svn: 241243
This matches the implementation of the gcc support for the same
feature, including checking the values set up by libgcc at runtime.
The structure looks like this:
unsigned int __cpu_vendor;
unsigned int __cpu_type;
unsigned int __cpu_subtype;
unsigned int __cpu_features[1];
with a set of enums to match various fields that are field out after
parsing the output of the cpuid instruction.
This also adds a set of errors checking for valid input (and cpu).
compiler-rt support for this and the other builtins in this family
(__builtin_cpu_init and __builtin_cpu_is) are forthcoming.
llvm-svn: 240994
The patch is generated using this command:
$ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
work/llvm/tools/clang
To reduce churn, not touching namespaces spanning less than 10 lines.
llvm-svn: 240270
This generalizes the checking of null arguments to also work with
values of pointer-to-function, reference-to-function, and block
pointer type, using the nullability information within the underling
function prototype to extend non-null checking, and diagnoses returns
of 'nil' within a function with a __nonnull return type.
Note that we don't warn about nil returns from Objective-C methods,
because it's common for Objective-C methods to mimic the nil-swallowing
behavior of the receiver by checking ostensibly non-null parameters
and returning nil from otherwise non-null methods in that
case.
It also diagnoses (via a separate flag) conversions from nullable to
nonnull pointers. It's a separate flag because this warning can be noisy.
llvm-svn: 240153
in section 10.1, __arm_{w,r}sr{,p,64}.
This includes arm_acle.h definitions with builtins and codegen to support
these, the intrinsics are implemented by generating read/write_register calls
which get appropriately lowered in the backend based on the register string
provided. SemaChecking is also implemented to fault invalid parameters.
Differential Revision: http://reviews.llvm.org/D9697
llvm-svn: 239737
The parameter types and return type do not need to be volatile just
because the pointer type's pointee type is volatile qualified. This is
an unnecessary pessimization.
llvm-svn: 238892
An AtomicType might be hidden behind arbitrary levels of typedefs.
getAs<> will reliably walk through the sugar to get the underlying
AtomicType.
This fixes PR23638.
llvm-svn: 238083
This adds low-level builtins to allow access to all of the z13 vector
instructions. Note that instructions whose semantics can be described
by standard C (including clang extensions) do not get any builtins.
For each instructions whose semantics *cannot* (fully) be described, we
define a builtin named __builtin_s390_<insn> that directly maps to this
instruction. These are intended to be compatible with GCC.
For instructions that also set the condition code, the builtin will take
an extra argument of type "int *" at the end. The integer pointed to by
this argument will be set to the post-instruction CC value.
For many instructions, the low-level builtin is mapped to the corresponding
LLVM IR intrinsic. However, a number of instructions can be represented
in standard LLVM IR without requiring use of a target intrinsic.
Some instructions require immediate integer operands within a certain
range. Those are verified at the Sema level.
Based on a patch by Richard Sandiford.
llvm-svn: 236532
This patch corresponds to review:
http://reviews.llvm.org/D8398
It adds some builtin functions to access the extended divide and bit permute instructions.
llvm-svn: 234547
A [*] is only allowed in a declaration for a function, not in its
definition. We didn't correctly recurse on reference types while
looking for it, causing us to crash in CodeGen instead of rejecting it.
llvm-svn: 234528
A [*] is only allowed in a declaration for a function, not in its
definition. We didn't correctly recurse while looking for it, causing
us to crash in CodeGen instead of rejecting it.
This fixes PR23151.
llvm-svn: 234363
The zEC12 provides the transactional-execution facility. This is exposed
to users via a set of builtin routines on other compilers. This patch
adds clang support to enable those builtins. In partciular, the patch:
- enables the transactional-execution feature by default on zEC12
- allows to override presence of that feature via the -mhtm/-mno-htm options
- adds a predefined macro __HTM__ if the feature is enabled
- adds support for the transactional-execution GCC builtins
- adds Sema checking to verify the __builtin_tabort abort code
- adds the s390intrin.h header file (for GCC compatibility)
- adds s390 sections to the htmintrin.h and htmxlintrin.h header files
Since this is first use of target-specific intrinsics on the platform,
the patch creates the include/clang/Basic/BuiltinsSystemZ.def file and
hooks it up in TargetBuiltins.h and lib/Basic/Targets.cpp.
An associated LLVM patch adds the required LLVM IR intrinsics.
For reference, the transactional-execution instructions are documented
in the z/Architecture Principles of Operation for the zEC12:
http://publibfp.boulder.ibm.com/cgi-bin/bookmgr/download/DZ9ZR009.pdf
The associated builtins are documented in the GCC manual:
http://gcc.gnu.org/onlinedocs/gcc/S_002f390-System-z-Built-in-Functions.html
The htmxlintrin.h intrinsics provided for compatibility with the IBM XL
compiler are documented in the "z/OS XL C/C++ Programming Guide".
llvm-svn: 233804
The argument range checks for the HTM and Crypto builtins were implemented in
CGBuiltin.cpp, not in Sema. This change moves them to the appropriate location
in SemaChecking.cpp. It requires the creation of a new method in the Sema class
to do checks for PPC-specific builtins.
http://reviews.llvm.org/D8672
llvm-svn: 233586
The diff looks intimidating, but this just moves the -Wdynamic-class-memaccess
code out a scope, protected by a
if (PointeeTy == QualType())
continue;
check so that it still only runs when it should.
llvm-svn: 232899
Summary: This patch consists of the suggestions of clang-tidy/misc-static-assert check.
Reviewers: alexfh
Subscribers: dblaikie, xazax.hun, cfe-commits
Differential Revision: http://reviews.llvm.org/D8344
Patch by Szabolcs Sipos!
llvm-svn: 232367
When if statement condition ended in a macro:
if (ptr == NULL);
the check used to consider the definition location of NULL, instead of the
current line.
Patch by Manasij Mukherjee.
llvm-svn: 232295
std::make_exception_ptr calls std::__GetExceptionInfo in order to figure
out how to properly copy the exception object.
Differential Revision: http://reviews.llvm.org/D8280
llvm-svn: 232188
This is nearly identical to the v*f128_si256 parts of r231792 and r232052.
AVX2 introduced proper integer variants of the hacked integer insert/extract
C intrinsics that were created for this same functionality with AVX1.
This should complete the front end fixes for insert/extract128 intrinsics.
Corresponding LLVM patch to follow.
llvm-svn: 232109
This is very much like D8088 (checked in at r231792).
Now that we've replaced the vinsertf128 intrinsics,
do the same for their extract twins.
Differential Revision: http://reviews.llvm.org/D8275
llvm-svn: 232052
We want to replace as much custom x86 shuffling via intrinsics
as possible because pushing the code down the generic shuffle
optimization path allows for better codegen and less complexity
in LLVM.
This is the sibling patch for the LLVM half of this change:
http://reviews.llvm.org/D8086
Differential Revision: http://reviews.llvm.org/D8088
llvm-svn: 231792
This commit adds new warning to prevent user from creating 'circular containers'.
Mutable collections from NSFoundation allows user to add collection to itself, e.g.:
NSMutableArray *a = [NSMutableArray new];
[a addObject:a];
The code above leads to really weird behaviour (crashes, 'endless' recursion) and
retain cycles (collection retains itself) if ARC enabled.
Patch checks the following collections:
- NSMutableArray,
- NSMutableDictionary,
- NSMutableSet,
- NSMutableOrderedSet,
- NSCountedSet.
llvm-svn: 231265
GCC -pedantic produces a format warning when the "%p" specifier is used with
arguments that are not void*. It's useful for portability to be able to
catch such warnings with clang as well. The warning is off by default in
both gcc and with this patch. This patch enables it either when extensions
are disabled with -pedantic, or with the specific flag -Wformat-pedantic.
The C99 and C11 specs do appear to require arguments corresponding to 'p'
specifiers to be void*: "If any argument is not the correct type for the
corresponding conversion specification, the behavior is undefined."
[7.19.6.1 p9], and of the 'p' format specifier "The argument shall be a
pointer to void." [7.19.6.1 p8]
Both printf and scanf format checking are covered.
llvm-svn: 231211
We'd diagnose an __assume expression which contained a function call.
This would result in us wrongly returning ExprError, causing mysterious
failures later on.
llvm-svn: 230597
This adds a new __freebsd_kprintf__ format string type, which enables
checking when used in __attribute__((format(...))) attributes. It can
check the FreeBSD kernel specific %b, %D, %r and %y specifiers, using
existing diagnostic messages. Also adds test cases for all these
specifiers.
Differential Revision: http://reviews.llvm.org/D7154
llvm-svn: 229921
The lowering looks a lot like normal EH lowering, with the exception
that the exceptions are caught by executing filter expression code
instead of matching typeinfo globals. The filter expressions are
outlined into functions which are used in landingpad clauses where
typeinfo would normally go.
Major aspects that still need work:
- Non-call exceptions in __try bodies won't work yet. The plan is to
outline the __try block in the frontend to keep things simple.
- Filter expressions cannot use local variables until capturing is
implemented.
- __finally blocks will not run after exceptions. Fixing this requires
work in the LLVM SEH preparation pass.
The IR lowering looks like this:
// C code:
bool safe_div(int n, int d, int *r) {
__try {
*r = normal_div(n, d);
} __except(_exception_code() == EXCEPTION_INT_DIVIDE_BY_ZERO) {
return false;
}
return true;
}
; LLVM IR:
define i32 @filter(i8* %e, i8* %fp) {
%ehptrs = bitcast i8* %e to i32**
%ehrec = load i32** %ehptrs
%code = load i32* %ehrec
%matches = icmp eq i32 %code, i32 u0xC0000094
%matches.i32 = zext i1 %matches to i32
ret i32 %matches.i32
}
define i1 zeroext @safe_div(i32 %n, i32 %d, i32* %r) {
%rr = invoke i32 @normal_div(i32 %n, i32 %d)
to label %normal unwind to label %lpad
normal:
store i32 %rr, i32* %r
ret i1 1
lpad:
%ehvals = landingpad {i8*, i32} personality i32 (...)* @__C_specific_handler
catch i8* bitcast (i32 (i8*, i8*)* @filter to i8*)
%ehptr = extractvalue {i8*, i32} %ehvals, i32 0
%sel = extractvalue {i8*, i32} %ehvals, i32 1
%filter_sel = call i32 @llvm.eh.seh.typeid.for(i8* bitcast (i32 (i8*, i8*)* @filter to i8*))
%matches = icmp eq i32 %sel, %filter_sel
br i1 %matches, label %eh.except, label %eh.resume
eh.except:
ret i1 false
eh.resume:
resume
}
Reviewers: rjmccall, rsmith, majnemer
Differential Revision: http://reviews.llvm.org/D5607
llvm-svn: 226760
Bitfield RefersToEnclosingLocal of Stmt::DeclRefExprBitfields renamed to RefersToCapturedVariable to reflect latest changes introduced in commit 224323. Also renamed method Expr::refersToEnclosingLocal() to Expr::refersToCapturedVariable() and comments for constant arguments.
No functional changes.
llvm-svn: 224329
The extension has the following syntax:
__builtin_call_with_static_chain(Call, Chain)
where Call must be a function call expression and Chain must be of pointer type
This extension performs a function call Call with a static chain pointer
Chain passed to the callee in a designated register. This is useful for
calling foreign language functions whose ABI uses static chain pointers
(e.g. to implement closures).
Differential Revision: http://reviews.llvm.org/D6332
llvm-svn: 224167
nonnull attribute when comparison is always true/false.
Original patch by Steven Wu. I have added extra code to prevent issuing of
warning when the nonnull parameter is modified prior to the comparison.
This addition prevents false positives in the most obvious cases.
There may still be false positive warnings in some cases (as one of my tests
indicates), but benefit far outweighs such cases. rdar://18712242
llvm-svn: 222264
Summary:
Ok, here is somewhat addition to D6217 aiming to preserve old darwin behavior wrt the typedefed types. The actual change to SemaChecking turned out to be pretty gross, in particular:
1. We need to extract the typedef'ed type for proper diagnostics
2. We need to walk over paren expressions as well
Reviewers: chandlerc, rsmith
Reviewed By: rsmith
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D6256
llvm-svn: 222044
parameters with nonnull attribute when comparison is always
true/false. Patch causes false positive when parameter is
modified in the function.
llvm-svn: 221163
nonnull attribute when comparison is always
true/false. Patch by Steven Wu with few fixes and minor
refactoring and adding tests by me. rdar://18712242
llvm-svn: 220496
and !=) to support mixed complex and real operand types.
This requires removing an assert from SemaChecking, and adding support
both to the constant evaluator and the code generator to synthesize the
imaginary part when needed. This seemed somewhat cleaner than having
just the comparison operators force real-to-complex conversions.
I've added test cases for these operations. I'm really terrified that
there were *no* tests in-tree which exercised this.
This turned up when trying to build R after my change to the complex
type lowering.
llvm-svn: 219570
Prior to GCC 4.4, __sync_fetch_and_nand was implemented as:
{ tmp = *ptr; *ptr = ~tmp & value; return tmp; }
but this was changed in GCC 4.4 to be:
{ tmp = *ptr; *ptr = ~(tmp & value); return tmp; }
in response to this change, support for sync_fetch_and_nand (and
sync_nand_and_fetch) was removed in r99522 in order to avoid miscompiling code
depending on the old semantics. However, at this point:
1. Many years have passed, and the amount of code relying on the old
semantics is likely smaller.
2. Through the work of many contributors, all LLVM backends have been updated
such that "atomicrmw nand" provides the newer GCC 4.4+ semantics (this process
was complete July of 2014 (added to the release notes in r212635).
3. The lack of this intrinsic is now a needless impediment to porting codes
from GCC to Clang (I've now seen several examples of this).
It is true, however, that we still set GNUC_MINOR to 2 (corresponding to GCC
4.2). To compensate for this, and to address the original concern regarding
code relying on the old semantics, I've added a warning that specifically
details the fact that the semantics have changed and that we provide the newer
semantics.
Fixes PR8842.
llvm-svn: 218905
Clang warns (treated as error by default, but still ignored in system headers)
when passing non-POD arguments to variadic functions, and generates a trap
instruction to crash the program if that code is ever run.
Unfortunately, MSVC happily generates code for such calls without a warning,
and there is code in system headers that use it.
This makes Clang not insert the trap instruction when in -fms-compatibility
mode, while still generating the warning/error message.
Differential Revision: http://reviews.llvm.org/D5492
llvm-svn: 218640
In addition to __builtin_assume_aligned, GCC also supports an assume_aligned
attribute which specifies the alignment (and optional offset) of a function's
return value. Here we implement support for the assume_aligned attribute by making
use of the @llvm.assume intrinsic.
llvm-svn: 218500
for __builtin___strlcpy_chk/__builtin___strlcat_chk.
Patch by Jacques Fortier with monir change by me and
addition of test. rdar://18259539
llvm-svn: 217700
off by default, issue a warning if %s directive is used
in formart argument of a function/method declared as
__attribute__((format(CF/NSString, ...)))
To complete rdar://18182443
llvm-svn: 217619
off by default, issue a warning if %s directive is used in
certain CF/NS formatting APIs, to assist user in deprecating
use of such %s in these APIs. rdar://18182443
llvm-svn: 217467
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
_Bool in C, if the macro is defined. Also teach FixItUtils to look at whether
the macro was defined at the source location for which it is creating a fixit,
rather than looking at whether it's defined *now*. This is especially relevant
for analysis-based warnings which are delayed until end of TU.
llvm-svn: 191057
LLVM supports applying conversion instructions to vectors of the same number of
elements (fptrunc, fptosi, etc.) but there had been no way for a Clang user to
cause such instructions to be generated when using builtin vector types.
C-style casting on vectors is already defined in terms of bitcasts, and so
cannot be used for these conversions as well (without leading to a very
confusing set of semantics). As a result, this adds a __builtin_convertvector
intrinsic (patterned after the OpenCL __builtin_astype intrinsic). This is
intended to aid the creation of vector intrinsic headers that create generic IR
instead of target-dependent intrinsics (in other words, this is a generic
_mm_cvtepi32_ps). As noted in the documentation, the action of
__builtin_convertvector is defined in terms of the action of a C-style cast on
each vector element.
llvm-svn: 190915
I changed the diagnostic printing code because it's probably better
to cut off a digit from DBL_MAX than to print something like
1.300000001 when the user wrote 1.3.
llvm-svn: 189625
Basically, isInMainFile considers line markers, and isWrittenInMainFile
doesn't. Distinguishing between the two is useful when dealing with
files which are preprocessed files or rewritten with -frewrite-includes
(so we don't, for example, print useless warnings).
llvm-svn: 188968
function: it can't be 'void' and it can't be an initializer list. We give a
hard error for these rather than treating them as undefined behavior (we can
and probably should do the same for non-POD types in C++11, but as of this
change we don't).
Slightly rework the checking of variadic arguments in a function with a format
attribute to ensure that certain kinds of format string problem (non-literal
string, too many/too few arguments, ...) don't suppress this error.
llvm-svn: 187735
Patch by Ana Pazos
- Completed implementation of instruction formats:
AdvSIMD three same
AdvSIMD modified immediate
AdvSIMD scalar pairwise
- Completed implementation of instruction classes
(some of the instructions in these classes
belong to yet unfinished instruction formats):
Vector Arithmetic
Vector Immediate
Vector Pairwise Arithmetic
- Initial implementation of instruction formats:
AdvSIMD scalar two-reg misc
AdvSIMD scalar three same
- Intial implementation of instruction class:
Scalar Arithmetic
- Initial clang changes to support arm v8 intrinsics.
Note: no clang changes for scalar intrinsics function name mangling yet.
- Comprehensive test cases for added instructions
To verify auto codegen, encoding, decoding, diagnosis, intrinsics.
llvm-svn: 187568
Previously a diagnostic was issued, but the code went ahead and built the ShuffleVectorExpr. While I'm here also simplify a couple lines by wrapping the return ExprError around the Diag calls.
llvm-svn: 187344
This adds three overloaded intrinsics to Clang:
T __builtin_arm_ldrex(const volatile T *addr)
int __builtin_arm_strex(T val, volatile T *addr)
void __builtin_arm_clrex()
The intent is that these do what users would expect when given most sensible
types. Currently, "sensible" translates to ints, floats and pointers.
llvm-svn: 186394
& operator (ignoring any overloaded operator& for the type). The purpose of
this builtin is for use in std::addressof, to allow it to be made constexpr;
the existing implementation technique (reinterpret_cast to some reference type,
take address, reinterpert_cast back) does not permit this because
reinterpret_cast between reference types is not permitted in a constant
expression in C++11 onwards.
llvm-svn: 186053
Use UsualArithmeticConversions unconditionally in analysis of
comparisons and conditional operators: the method performs
the usual arithmetic conversions if both sides are arithmetic, and
usual unary conversions if they are not. This is just a cleanup
for conditional operators; for comparisons, it fixes the issue that
we would try to check isArithmetic() on an atomic type.
Also, fix GetExprRange() in SemaChecking.cpp so it deals with variables
of atomic type correctly.
Fixes PR15537.
llvm-svn: 185857
before the value computation of the result. In C, this is implied by there being
a sequence point after their evaluation, and in C++, it's implied by the
side-effects being sequenced before the expressions and statements in the
function body.
llvm-svn: 185282
side-effect is not sequenced before its value computation. Also fix a
mishandling of ?: expressions where the condition is constant that was
exposed by the tests for this.
llvm-svn: 185035
Itanium destroys them in the caller at the end of the full expression,
but MSVC destroys them in the callee. This is further complicated by
the need to emit EH-only destructor cleanups in the caller.
This should help clang compile MSVC's debug iterators more correctly.
There is still an outstanding issue in PR5064 of a memcpy emitted by the
LLVM backend, which is not correct for C++ records.
Fixes PR16226.
Reviewers: rjmccall
Differential Revision: http://llvm-reviews.chandlerc.com/D929
llvm-svn: 184543
operations in the case where evaluating a subexpression fails. No functionality
change, but test/Sema/many-logical-ops.c gets ~100x faster with this change.
llvm-svn: 184489
In some cases, clang applies the C++ rules for computing the range of a
value when said value is an enum.
Instead, apply C semantics when in C mode.
llvm-svn: 183084
- References to ObjC bit-field ivars are bit-field lvalues;
fixes rdar://13794269, which got me started down this.
- Introduce Expr::refersToBitField, switch a couple users to
it where semantically important, and comment the difference
between this and the existing API.
- Discourage Expr::getBitField by making it a bit longer and
less general-sounding.
- Lock down on const_casts of bit-field gl-values until we
hear back from the committee as to whether they're allowed.
llvm-svn: 181252