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 66ddac22e2.
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
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
In CUDA/HIP a function may become implicit host device function by
pragma or constexpr. A host device function is checked in both
host and device compilation. However it may be emitted only
on host or device side, therefore the diagnostics should be
deferred until it is known to be emitted.
Currently clang is only able to defer certain diagnostics. This causes
false alarms and limits the usefulness of host device functions.
This patch lets clang defer all overloading resolution diagnostics for host device functions.
An option -fgpu-defer-diag is added to control this behavior. By default
it is off.
It is NFC for other languages.
Differential Revision: https://reviews.llvm.org/D84364
This change implements pragma STDC FENV_ROUND, which is introduced by
the extension to standard (TS 18661-1). The pragma is implemented only
in frontend, it sets apprpriate state of FPOptions stored in Sema. Use
of these bits in constant evaluation adn/or code generator is not in the
scope of this change.
Parser issues warning on unsuppored pragma when it encounteres pragma
STDC FENV_ROUND, however it makes syntax checks and updates Sema state
as if the pragma were supported.
Primary purpose of the partial implementation is to facilitate
development of non-default floating poin environment. Previously a
developer cannot set non-default rounding mode in sources, this mades
preparing tests for say constant evaluation substantially complicated.
Differential Revision: https://reviews.llvm.org/D86921
Reapply 49e5f603d4
which had been reverted in c94332919b.
Originally reverted because I hadn't updated it in quite a while when I
got around to committing it, so there were a bunch of missing changes to
new code since I'd written the patch.
Reviewers: aaron.ballman
Differential Revision: https://reviews.llvm.org/D76646
There is a version that just tests (also called
isIntegerConstantExpression) & whereas this version is specifically used
when the value is of interest (a few call sites were actually refactored
to calling the test-only version) so let's make the API look more like
it.
Reviewers: aaron.ballman
Differential Revision: https://reviews.llvm.org/D76646
Found by linker failures in ThinLTO where the definition wasn't
available when it needed to be. (eg: ThinLTO may've eliminated the one
caller in the same TU and dropped the definition - breaking accidental
implicit depenednce on that definition from elsewhere)
This reverts commit defd43a5b3.
with correction to solve msan report
To solve https://bugs.llvm.org/show_bug.cgi?id=46166 where the
floating point settings in PCH files aren't compatible, rewrite
FPFeatures to use a delta in the settings rather than absolute settings.
With this patch, these floating point options can be benign.
Reviewers: rjmccall
Differential Revision: https://reviews.llvm.org/D81869
This reverts commit b55d723ed6.
Reapply Modify FPFeatures to use delta not absolute settings
To solve https://bugs.llvm.org/show_bug.cgi?id=46166 where the
floating point settings in PCH files aren't compatible, rewrite
FPFeatures to use a delta in the settings rather than absolute settings.
With this patch, these floating point options can be benign.
Reviewers: rjmccall
Differential Revision: https://reviews.llvm.org/D81869
Summary: #pragma float_control(pop) was failing to restore the expected
floating point settings because the settings were not correctly preserved
at #pragma float_control(push).
Summary: Erroneous error diagnostic observed in VS2017 <numeric> header
Also correction to propagate usesFPIntrin from template func to instantiation.
Reviewers: rjmccall, erichkeane (no feedback received)
Differential Revision: https://reviews.llvm.org/D79631
Summary:
Conflicting types for the same section name defined in clang section
pragmas and GNU-style section attributes were not properly captured by
Clang's Sema. The lack of diagnostics was caused by the fact the section
specification coming from attributes was handled by Sema as implicit,
even though explicitly defined by the user.
This patch enables the diagnostics for section type conflicts between
those specifications by making sure sections defined in section
attributes are correctly handled as explicit.
Reviewers: hans, rnk, javed.absar
Reviewed By: rnk
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D78573
Summary:
Section names used in clang section pragmas were not validated against
previously defined sections, causing section type conflicts to be
ignored by Sema.
This patch enables Clang to capture these section type conflicts by
using the existing Sema's UnifySection method to validate section names
from clang section pragmas.
Reviewers: hans, rnk, javed.absar
Reviewed By: rnk
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D78572
test cases
Add support for #pragma float_control
Reviewers: rjmccall, erichkeane, sepavloff
Differential Revision: https://reviews.llvm.org/D72841
This reverts commit 85dc033cac, and makes
corrections to the test cases that failed on buildbots.
Now compiler defines 5 sets of constants to represent rounding mode.
These are:
1. `llvm::APFloatBase::roundingMode`. It specifies all 5 rounding modes
defined by IEEE-754 and is used in `APFloat` implementation.
2. `clang::LangOptions::FPRoundingModeKind`. It specifies 4 of 5 IEEE-754
rounding modes and a special value for dynamic rounding mode. It is used
in clang frontend.
3. `llvm::fp::RoundingMode`. Defines the same values as
`clang::LangOptions::FPRoundingModeKind` but in different order. It is
used to specify rounding mode in in IR and functions that operate IR.
4. Rounding mode representation used by `FLT_ROUNDS` (C11, 5.2.4.2.2p7).
Besides constants for rounding mode it also uses a special value to
indicate error. It is convenient to use in intrinsic functions, as it
represents platform-independent representation for rounding mode. In this
role it is used in some pending patches.
5. Values like `FE_DOWNWARD` and other, which specify rounding mode in
library calls `fesetround` and `fegetround`. Often they represent bits
of some control register, so they are target-dependent. The same names
(not values) and a special name `FE_DYNAMIC` are used in
`#pragma STDC FENV_ROUND`.
The first 4 sets of constants are target independent and could have the
same numerical representation. It would simplify conversion between the
representations. Also now `clang::LangOptions::FPRoundingModeKind` and
`llvm::fp::RoundingMode` do not contain the value for IEEE-754 rounding
direction `roundTiesToAway`, although it is supported natively on
some targets.
This change defines all the rounding mode type via one `llvm::RoundingMode`,
which also contains rounding mode for IEEE rounding direction `roundTiesToAway`.
Differential Revision: https://reviews.llvm.org/D77379
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
This change added two new attributes, rounding mode and exception
behavior to the structure FPOptions. These attributes allow more
flexible treatment of specific floating point environment than it is
provided by #pragma STDC FENV_ACCESS.
Differential Revision: https://reviews.llvm.org/D65994
Zahira Ammarguellat