Just follow along with the reassociate pragma. This allows locally
setting the arcp fast math flag. Previously you could only access this
through the global -freciprocal-math.
Fixes#64798
This patch adds static functions for constructing most
AttributeCommonInfo::Forms. Direct construction is only retained where
all fields (currently the syntax and spelling) are specified explicitly.
This is a wash on its own. The purpose is to allow extra fields
to be added to Form without disrupting all callers. In particular,
it allows extra information to be stored about keywords without
affecting non-keyword uses.
No functional change intended.
Differential Revision: https://reviews.llvm.org/D148104
When constructing an attribute, the syntactic form was specified
using two arguments: an attribute-independent syntax type and an
attribute-specific spelling index. This patch replaces them with
a single argument.
In most cases, that's done using a new Form class that combines the
syntax and spelling into a single object. This has the minor benefit
of removing a couple of constructors. But the main purpose is to allow
additional information to be stored as well, beyond just the syntax and
spelling enums.
In the case of the attribute-specific Create and CreateImplicit
functions, the patch instead uses the attribute-specific spelling
enum. This helps to ensure that the syntax and spelling are
consistent with each other and with the Attr.td definition.
If a Create or CreateImplicit caller specified a syntax and
a spelling, the patch drops the syntax argument and keeps the
spelling. If the caller instead specified only a syntax
(so that the spelling was SpellingNotCalculated), the patch
simply drops the syntax argument.
There were two cases of the latter: TargetVersion and Weak.
TargetVersionAttrs were created with GNU syntax, which matches
their definition in Attr.td, but which is also the default.
WeakAttrs were created with Pragma syntax, which does not match
their definition in Attr.td. Dropping the argument switches
them to AS_GNU too (to match [GCC<"weak">]).
Differential Revision: https://reviews.llvm.org/D148102
In strict mode the 'roundin_mode' is set to 'dynamic'. Using this pragma to
get out of strict mode doesn't have any effect on the 'rounding_mode'.
See https://godbolt.org/z/zoGTf4j1G
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D147733
POWER Darwin support in the backend has been removed for some time: https://discourse.llvm.org/t/rfc-remove-darwin-support-from-power-backends
but Clang still has the TargetInfo and other remnants lying around.
This patch does some cleanup and removes those and other related frontend support still remaining. We adjust any tests using the triple to either remove
the test if unneeded or switch to another Power triple.
Reviewed By: MaskRay, nemanjai
Differential Revision: https://reviews.llvm.org/D146459
Setting __FLT_EVAL_METHOD__ to -1 with fast-math will set
__GLIBC_FLT_EVAL_METHOD to 2 and long double ends up being used for
float_t and double_t. This creates some ABI breakage with various C libraries.
See details here: https://github.com/llvm/llvm-project/issues/60781
This reverts commit bbf0d1932a3c1be970ed8a580e51edf571b80fd5.
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
MSVC's pragma alloc_text accepts a function that was redeclared in
a non extern-C context if the previous declaration was in an extern-C
context. i.e.
```
extern "C" { static void f(); }
static void f();
```
MSVC's pragma alloc_text also rejects non-functions.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D128649
MSVC's pragma optimize turns optimizations on or off based on the list
passed. At the moment, we only support an empty optimization list.
i.e. `#pragma optimize("", on | off)`
From MSVC's docs:
| Parameter | Type of optimization |
|-----------|--------------------------------------------------|
| g | Enable global optimizations. Deprecated |
| s or t | Specify short or fast sequences of machine code |
| y | Generate frame pointers on the program stack |
https://docs.microsoft.com/en-us/cpp/preprocessor/optimize?view=msvc-170
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D125723
Previously `#pragma STDC FENV_ACCESS ON` always set dynamic rounding
mode and strict exception handling. It is not correct in the presence
of other pragmas that also modify rounding mode and exception handling.
For example, the effect of previous pragma FENV_ROUND could be
cancelled, which is not conformant with the C standard. Also
`#pragma STDC FENV_ACCESS OFF` turned off only FEnvAccess flag, leaving
rounding mode and exception handling unchanged, which is incorrect in
general case.
Concrete rounding and exception mode depend on a combination of several
factors like various pragmas and command-line options. During the review
of this patch an idea was proposed that the semantic actions associated
with such pragmas should only set appropriate flags. Actual rounding
mode and exception handling should be calculated taking into account the
state of all relevant options. In such implementation the pragma
FENV_ACCESS should not override properties set by other pragmas but
should set them if such setting is absent.
To implement this approach the following main changes are made:
- Field `FPRoundingMode` is removed from `LangOptions`. Actually there
are no options that set it to arbitrary rounding mode, the choice was
only `dynamic` or `tonearest`. Instead, a new boolean flag
`RoundingMath` is added, with the same meaning as the corresponding
command-line option.
- Type `FPExceptionModeKind` now has possible value `FPE_Default`. It
does not represent any particular exception mode but indicates that
such mode was not set and default value should be used. It allows to
distinguish the case:
{
#pragma STDC FENV_ACCESS ON
...
}
where the pragma must set FPE_Strict, from the case:
{
#pragma clang fp exceptions(ignore)
#pragma STDC FENV_ACCESS ON
...
}
where exception mode should remain `FPE_Ignore`.
- Class `FPOptions` has now methods `getRoundingMode` and
`getExceptionMode`, which calculates the respective properties from
other specified FP properties.
- Class `LangOptions` has now methods `getDefaultRoundingMode` and
`getDefaultExceptionMode`, which calculates default modes from the
specified options and should be used instead of `getRoundingMode` and
`getFPExceptionMode` of the same class.
Differential Revision: https://reviews.llvm.org/D126364
`isExternCContext()` is returning false for functions in C files
Reviewed By: rnk, aaron.ballman
Differential Revision: https://reviews.llvm.org/D126559
compiler is allowed to use optimizations that allow reassociation and
transformations that don’t guaranty accuracy.
For example (x+y)+z is transformed into x+(y+z) . Although
mathematically equivalent, these two expressions may not lead to the
same final result due to errors of summation.
Or x/x is transformed into 1.0 but x could be 0.0, INF or NaN. And so
this transformation also may not lead to the same final result.
Setting the eval method 'ffp-eval-method' or via '#pragma clang fp
eval_method' in this mode, doesn’t have any effect.
This patch adds code to warn the user of this.
Differential Revision: https://reviews.llvm.org/D122155
FLT_EVAL_METHOD tells the user the precision at which, temporary results
are evaluated but when fast-math is enabled, the numeric values are not
guaranteed to match the source semantics, so the eval-method is
meaningless.
For example, the expression `x + y + z` has as source semantics `(x + y)
+ z`. FLT_EVAL_METHOD is telling the user at which precision `(x + y)`
is evaluated. With fast-math enable the compiler can choose to
evaluate the expression as `(y + z) + x`.
The correct behavior is to set the FLT_EVAL_METHOD to `-1` to tell the
user that the precision of the intermediate values is unknow. This
patch is doing that.
Differential Revision: https://reviews.llvm.org/D121122
These changes make the Clang parser recognize expression parameter pack
expansion and initializer lists in attribute arguments. Because
expression parameter pack expansion requires additional handling while
creating and instantiating templates, the support for them must be
explicitly supported through the AcceptsExprPack flag.
Handling expression pack expansions may require a delay to when the
arguments of an attribute are correctly populated. To this end,
attributes that are set to accept these - through setting the
AcceptsExprPack flag - will automatically have an additional variadic
expression argument member named DelayedArgs. This member is not
exposed the same way other arguments are but is set through the new
CreateWithDelayedArgs creator function generated for applicable
attributes.
To illustrate how to implement support for expression pack expansion
support, clang::annotate is made to support pack expansions. This is
done by making handleAnnotationAttr delay setting the actual attribute
arguments until after template instantiation if it was unable to
populate the arguments due to dependencies in the parsed expressions.
This avoids an unnecessary copy required by 'return OS.str()', allowing
instead for NRVO or implicit move. The .str() call (which flushes the
stream) is no longer required since 65b13610a5226b84889b923bae884ba395ad084d,
which made raw_string_ostream unbuffered by default.
Differential Revision: https://reviews.llvm.org/D115374
Fixes a compiler assert on passing a compile time integer to atomic builtins.
Assert introduced in D61522
Function changed from ->bool to ->Optional in D76646
Simplifies call sites to getIntegerConstantExpr to elide the now-redundant
isValueDependent checks.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D112159
The intent of this patch is to add support of -fp-model=[source|double|extended] to allow
the compiler to use a wider type for intermediate floating point calculations. As a side
effect to that, the value of FLT_EVAL_METHOD is changed according to the pragma
float_control.
Unfortunately some issue was uncovered with this change in preprocessing. See details in
https://reviews.llvm.org/D93769 . We are therefore reverting this patch until we find a way
to reconcile the value of FLT_EVAL_METHOD, the pragma and the -E flow.
This reverts commit 66ddac22e2a7f268e91c26d694112970dfa607ae.
The Intel compiler ICC supports the option "-fp-model=(source|double|extended)"
which causes the compiler to use a wider type for intermediate floating point
calculations. Also supported is a way to embed this effect in the source
program with #pragma float_control(source|double|extended).
This patch extends pragma float_control syntax, and also adds support
for a new floating point option "-ffp-eval-method=(source|double|extended)".
source: intermediate results use source precision
double: intermediate results use double precision
extended: intermediate results use extended precision
Reviewed By: Aaron Ballman
Differential Revision: https://reviews.llvm.org/D93769
Currently, we prohibit this pragma from appearing within a language
linkage specification, but this is useful functionality that is
supported by MSVC (which is where we inherited this feature from).
This patch allows you to use the pragma within an extern "C" {} (etc)
block.
The Intel compiler ICC supports the option "-fp-model=(source|double|extended)"
which causes the compiler to use a wider type for intermediate floating point
calculations. Also supported is a way to embed this effect in the source
program with #pragma float_control(source|double|extended).
This patch extends pragma float_control syntax, and also adds support
for a new floating point option "-ffp-eval-method=(source|double|extended)".
source: intermediate results use source precision
double: intermediate results use double precision
extended: intermediate results use extended precision
Reviewed By: Aaron Ballman
Differential Revision: https://reviews.llvm.org/D93769
Reduces numbers of files built for clang-format from 575 to 449.
Requires two small changes:
1. Don't use llvm::ExceptionHandling in LangOptions. This isn't
even quite the right type since we don't use all of its values.
Tweaks the changes made in:
- https://reviews.llvm.org/D93215
- https://reviews.llvm.org/D93216
2. Move section name validation code added (long ago) in commit 30ba67439 out
of libBasic into Sema and base the check on the triple. This is a bit less
OOP-y, but completely in line with what we do in many other places in Sema.
No behavior change.
Differential Revision: https://reviews.llvm.org/D101463
Currently, when one or more attributes are mutually exclusive, the
developer adding the attribute has to manually emit diagnostics. In
practice, this is highly error prone, especially for declaration
attributes, because such checking is not trivial. Redeclarations
require you to write a "merge" function to diagnose mutually exclusive
attributes and most attributes get this wrong.
This patch introduces a table-generated way to specify that a group of
two or more attributes are mutually exclusive:
def : MutualExclusions<[Attr1, Attr2, Attr3]>;
This works for both statement and declaration attributes (but not type
attributes) and the checking is done either from the common attribute
diagnostic checking code or from within mergeDeclAttribute() when
merging redeclarations.
Clang currently automates a fair amount of diagnostic checking for
declaration attributes based on the declarations in Attr.td. It checks
for things like subject appertainment, number of arguments, language
options, etc. This patch uses the same machinery to perform diagnostic
checking on statement attributes.
This patch renames PackStack and related variable names to also contain align across Clang.
As it is right now, Clang already uses one stack to record the information from both #pragma
align and #pragma pack. Leaving it as PackStack is confusing, and could cause people to
ignore #pragma align when developing code that interacts with PackStack.
Differential Revision: https://reviews.llvm.org/D93901
If two variables are declared with __attribute__((section(name))) and
the implicit section types (e.g. read only vs writeable) conflict, an
error is raised. Extend this mechanism so that an error is raised if the
section type implied by a function's __attribute__((section)) conflicts
with that of another variable.
Recently HIP toolchain made a change to use clang instead of opt/llc to do compilation
(https://reviews.llvm.org/D81861). The intention is to make HIP toolchain canonical like
other toolchains.
However, this change introduced an unintentional change regarding backend fp fuse
option, which caused regressions in some HIP applications.
Basically before the change, HIP toolchain used clang to generate bitcode, then use
opt/llc to optimize bitcode and generate ISA. As such, the amdgpu backend takes
the default fp fuse mode which is 'Standard'. This mode respect contract flag of
fmul/fadd instructions and do not fuse fmul/fadd instructions without contract flag.
However, after the change, HIP toolchain now use clang to generate IR, do optimization,
and generate ISA as one process. Now amdgpu backend fp fuse option is determined
by -ffp-contract option, which is 'fast' by default. And this -ffp-contract=fast language option
is translated to 'Fast' fp fuse option in backend. Suddenly backend starts to fuse fmul/fadd
instructions without contract flag.
This causes wrong result for some device library functions, e.g. tan(-1e20), which should
return 0.8446, now returns -0.933. What is worse is that since backend with 'Fast' fp fuse
option does not respect contract flag, there is no way to use #pragma clang fp contract
directive to enforce fp contract requirements.
This patch fixes the regression by introducing a new value 'fast-honor-pragmas' for -ffp-contract
and use it for HIP by default. 'fast-honor-pragmas' is equivalent to 'fast' in frontend but
let the backend to use 'Standard' fp fuse option. 'fast-honor-pragmas' is useful since 'Fast'
fp fuse option in backend does not honor contract flag, it is of little use to HIP
applications since all code with #pragma STDC FP_CONTRACT or any IR from a
source compiled with -ffp-contract=on is broken.
Differential Revision: https://reviews.llvm.org/D90174
Pragma 'clang fp' is extended to support a new option, 'exceptions'. It
allows to specify floating point exception behavior more flexibly.
Differential Revision: https://reviews.llvm.org/D89849
This recommits 7f1f89ec8d9944559042bb6d3b1132eabe3409de and
40df06cdafc010002fc9cfe1dda73d689b7d27a6 with bug fixes for
memory sanitizer failure and Tensile build failure.
The change implements evaluation of constant floating point expressions
under non-default rounding modes. The main objective was to support
evaluation of global variable initializers, where constant rounding mode
may be specified by `#pragma STDC FENV_ROUND`.
Differential Revision: https://reviews.llvm.org/D87822