Summary:
Before this change, we only emit the XRay attributes in LLVM IR when the
-fxray-instrument flag is provided. This may cause issues with thinlto
when the final binary is being built/linked with -fxray-instrument, and
the constitutent LLVM IR gets re-lowered with xray instrumentation.
With this change, we can honour the "never-instrument "attributes
provided in the source code and preserve those in the IR. This way, even
in thinlto builds, we retain the attributes which say whether functions
should never be XRay instrumented.
This change addresses llvm.org/PR38922.
Reviewers: mboerger, eizan
Subscribers: mehdi_amini, dexonsmith, cfe-commits, llvm-commits
Differential Revision: https://reviews.llvm.org/D52015
llvm-svn: 342200
Previously, both types (plus the future target-clones) of
multiversioning had a separate ResolverOption structure and emission
function. This patch combines the two, at the expense of a slightly
more expensive sorting function.
llvm-svn: 342152
Previously the alignment on the newly created rtti/typeinfo data was largely
not set, meaning that DataLayout::getPreferredAlignment was free to overalign
it to 16 bytes. This causes unnecessary code bloat.
Differential Revision: https://reviews.llvm.org/D51416
llvm-svn: 342053
'declare target'.
All the functions, referenced in implicit|explicit target regions must
be emitted during code emission for the device.
llvm-svn: 341093
Since MinGW supports automatically importing external variables from
DLLs even without the DLLImport attribute, we shouldn't mark them
as DSO local unless we actually know them to be local for sure.
Keep marking thread local variables as DSO local.
Differential Revision: https://reviews.llvm.org/D51382
llvm-svn: 340941
constants by default when there is no optimization.
GCC's option -fno-keep-static-consts can be used to not emit
unused static constants.
In Clang, since default behavior does not keep unused static constants,
-fkeep-static-consts can be used to emit these if required. This could be
useful for producing identification strings like SVN identifiers
inside the object file even though the string isn't used by the program.
Differential Revision: https://reviews.llvm.org/D40925
llvm-svn: 340439
If the function is actually a weak reference, it should not be marked as
deferred definition as this is only a declaration. Patch adds checks for
the definitions if they must be emitted. Otherwise, only declaration is
emitted.
llvm-svn: 340191
The compiler may produce unexpected error messages/crashes when declare
target variables were used. Patch fixes problems with the declarations
marked as declare target to or link.
llvm-svn: 339805
This extension emits the guard cf table without inserting the
instrumentation. Currently that's what clang-cl does with /guard:cf
anyway, but this allows a user to request that explicitly.
Differential Revision: https://reviews.llvm.org/D50513
llvm-svn: 339420
declare target.
According to OpenMP 5.0, variables captured in lambdas in declare target
regions must be considered as implicitly declare target.
llvm-svn: 339152
CUDA 8.0 E.3.9.4 says: Within the body of a __device__ or __global__
function, only __shared__ variables or variables without any device
memory qualifiers may be declared with static storage class.
It is unclear how a function-scope non-const static variable
without device memory qualifier is implemented, therefore only static
const variable without device memory qualifier is allowed, which
can be emitted as a global variable in constant address space.
Currently clang only allows function-scope static variable with
__shared__ qualifier.
This patch also allows function-scope static const variable without
device memory qualifier and emits it as a global variable in constant
address space.
Differential Revision: https://reviews.llvm.org/D49931
llvm-svn: 338188
As documented here: https://software.intel.com/en-us/node/682969 and
https://software.intel.com/en-us/node/523346. cpu_dispatch multiversioning
is an ICC feature that provides for function multiversioning.
This feature is implemented with two attributes: First, cpu_specific,
which specifies the individual function versions. Second, cpu_dispatch,
which specifies the location of the resolver function and the list of
resolvable functions.
This is valuable since it provides a mechanism where the resolver's TU
can be specified in one location, and the individual implementions
each in their own translation units.
The goal of this patch is to be source-compatible with ICC, so this
implementation diverges from the ICC implementation in a few ways:
1- Linux x86/64 only: This implementation uses ifuncs in order to
properly dispatch functions. This is is a valuable performance benefit
over the ICC implementation. A future patch will be provided to enable
this feature on Windows, but it will obviously more closely fit ICC's
implementation.
2- CPU Identification functions: ICC uses a set of custom functions to identify
the feature list of the host processor. This patch uses the cpu_supports
functionality in order to better align with 'target' multiversioning.
1- cpu_dispatch function def/decl: ICC's cpu_dispatch requires that the function
marked cpu_dispatch be an empty definition. This patch supports that as well,
however declarations are also permitted, since the linker will solve the
issue of multiple emissions.
Differential Revision: https://reviews.llvm.org/D47474
llvm-svn: 337552
This patch uses CodeSegAttr to represent __declspec(code_seg) rather than
building on the existing support for #pragma code_seg.
The code_seg declspec is applied on functions and classes. This attribute
enables the placement of code into separate named segments, including compiler-
generated codes and template instantiations.
For more information, please see the following:
https://msdn.microsoft.com/en-us/library/dn636922.aspx
This patch fixes the regression for the support for attribute ((section).
https://github.com/llvm-mirror/clang/commit/746b78de7812bc785fbb5207b788348040b23fa7
Patch by Soumi Manna (Manna)
Differential Revision: https://reviews.llvm.org/D48841
llvm-svn: 337420
Code in `CodeGenModule::SetFunctionAttributes()` could set an empty
attribute `implicit-section-name` on a function that is affected by
`#pragma clang text="section"`. This is incorrect because the attribute
should contain a valid section name. If the function additionally also
used `__attribute__((section("section")))` then this could result in
emitting the function in a section with an empty name.
The patch fixes the issue by removing the problematic code that sets
empty `implicit-section-name` from
`CodeGenModule::SetFunctionAttributes()` because it is sufficient to set
this attribute only from a similar code in `setNonAliasAttributes()`
when the function is emitted.
Differential Revision: https://reviews.llvm.org/D48916
llvm-svn: 336842
This matches the way NVCC does it. Doing module cleanup at global
destructor phase used to work, but is, apparently, too late for
the CUDA runtime in CUDA-9.2, which ends up crashing with double-free.
Differential Revision: https://reviews.llvm.org/D48613
llvm-svn: 335763
Similarly to CFI on virtual and indirect calls, this implementation
tries to use program type information to make the checks as precise
as possible. The basic way that it works is as follows, where `C`
is the name of the class being defined or the target of a call and
the function type is assumed to be `void()`.
For virtual calls:
- Attach type metadata to the addresses of function pointers in vtables
(not the functions themselves) of type `void (B::*)()` for each `B`
that is a recursive dynamic base class of `C`, including `C` itself.
This type metadata has an annotation that the type is for virtual
calls (to distinguish it from the non-virtual case).
- At the call site, check that the computed address of the function
pointer in the vtable has type `void (C::*)()`.
For non-virtual calls:
- Attach type metadata to each non-virtual member function whose address
can be taken with a member function pointer. The type of a function
in class `C` of type `void()` is each of the types `void (B::*)()`
where `B` is a most-base class of `C`. A most-base class of `C`
is defined as a recursive base class of `C`, including `C` itself,
that does not have any bases.
- At the call site, check that the function pointer has one of the types
`void (B::*)()` where `B` is a most-base class of `C`.
Differential Revision: https://reviews.llvm.org/D47567
llvm-svn: 335569
Currently clang set kernel calling convention for CUDA/HIP after
arranging function, which causes incorrect kernel function type since
it depends on calling convention.
This patch moves setting kernel convention before arranging
function.
Differential Revision: https://reviews.llvm.org/D47733
llvm-svn: 334457
This should reduce the binary size penalty of ASan on Windows. After
r334313, ASan will add red zones to globals in comdats, so we will still
find OOB accesses to string literals.
llvm-svn: 334417
Summary:
When requirement imposed by __target__ attributes on functions
are not satisfied, prefer printing those requirements, which
are explicitly mentioned in the attributes.
This makes such messages more useful, e.g. printing avx512f instead of avx2
in the following scenario:
```
$ cat foo.c
static inline void __attribute__((__always_inline__, __target__("avx512f")))
x(void)
{
}
int main(void)
{
x();
}
$ clang foo.c
foo.c:7:2: error: always_inline function 'x' requires target feature 'avx2', but would be inlined into function 'main' that is compiled without support for 'avx2'
x();
^
1 error generated.
```
bugzilla: https://bugs.llvm.org/show_bug.cgi?id=37338
Reviewers: craig.topper, echristo, dblaikie
Reviewed By: craig.topper, echristo
Differential Revision: https://reviews.llvm.org/D46541
llvm-svn: 334174
Dean Michael Berris
Erich Keane
David Green
Reid Kleckner
Alexey Bataev
Martin Storsjo
Elizabeth Andrews
Hans Wennborg
Stephen Kelly
Fangrui Song
Yaxun Liu
Petr Pavlu
Artem Belevich
Evgeniy Stepanov
Peter Collingbourne
Gabor Buella