Summary:
This patch reworks how we handle global constructors in OpenMP.
Previously, we emitted individual kernels that were all registered and
called individually. In order to provide more generic support, this
patch moves all handling of this to the target backend and the runtime
plugin. This has the benefit of supporting the GNU extensions for
constructors an destructors, removing a class of failures related to
shared library destruction order, and allows targets other than OpenMP
to use the same support without needing to change the frontend.
This is primarily done by calling kernels that the backend emits to
iterate a list of ctor / dtor functions. For x64, this is automatic and
we get it for free with the standard `dlopen` handling. For AMDGPU, we
emit `amdgcn.device.init` and `amdgcn.device.fini` functions which
handle everything atuomatically and simply need to be called. For NVPTX,
a patch https://github.com/llvm/llvm-project/pull/71549 provides the
kernels to call, but the runtime needs to set up the array manually by
pulling out all the known constructor / destructor functions.
One concession that this patch requires is the change that for GPU
targets in OpenMP offloading we will use `llvm.global_dtors` instead of
using `atexit`. This is because `atexit` is a separate runtime function
that does not mesh well with the handling we're trying to do here. This
should be equivalent in all cases except for cases where we would need
to destruct manually such as:
```
struct S { ~S() { foo(); } };
void foo() {
static S s;
}
```
However this is broken in many other ways on the GPU, so it is not
regressing any support, simply increasing the scope of what we can
handle.
This changes the handling of ctors / dtors. This patch now outputs a
information message regarding the deprecation if the old format is used.
This will be completely removed in a later release.
Depends on: https://github.com/llvm/llvm-project/pull/71549
This patch converts `ImplicitParamDecl::ImplicitParamKind` into a scoped enum at namespace scope, making it eligible for forward declaring. This is useful for `preferred_type` annotations on bit-fields.
Close https://github.com/llvm/llvm-project/issues/67893
The root cause of the crash is an oversight that we missed the point
that the same module can be imported multiple times. And we should use
`SmallSetVector` instead of `SmallVector` to filter the case.
I just found that we didn't handle the imports in GMF of PMF when we're
generating the init functions for the current module unit. This looks
like a simple oversight and I'm going to fix that in this patch
directly.
Close https://github.com/llvm/llvm-project/issues/56794
And see https://github.com/llvm/llvm-project/issues/67582 for a detailed
backgrond for the issue.
As required by the Itanium ABI, the module units have to generate the
initialization function. However, the importers are allowed to elide the
call to the initialization function if they are sure the initialization
function doesn't do anything.
This patch implemented this semantics.
Turned out we were making overly simple assumptions about which sections (& section flags) would be used when emitting a global into a custom section. This lead to sections with read-only flags being used for globals of struct types with mutable members.
Fixed by porting the codegen function with the more nuanced handling/checking for mutable members out of codegen for use in the sema code that does this initial checking/mapping to section flags.
Differential Revision: https://reviews.llvm.org/D156726
Partial progress towards replacing in-tree uses of `Type::getPointerTo()`.
This needs to be done before deprecating the API.
Reviewed By: nikic, barannikov88
Differential Revision: https://reviews.llvm.org/D152321
The original name "ASTContext::getNamedModuleForCodeGen" is not properly
reflecting the usage of the interface. This interface can be used to
judge the current module unit in both sema analysis and code generation.
So the original name was not so correct.
Decl::isInCurrentModuleUnit
Refactor `Sema::isModuleUnitOfCurrentTU` to `Decl::isInCurrentModuleUnit`
to make code simpler a little bit. Note that although this patch
introduces a FIXME, this is an existing issue and this patch just tries
to describe it explicitly.
We need to be able to distinguish individual TUs from the same module in cases
where TU-local entities either need to be hidden (or, for some cases of ADL in
template instantiation, need to be detected as exposures).
This creates a module type for the implementation which implicitly imports its
primary module interface per C++20:
[module.unit/8] 'A module-declaration that contains neither an export-keyword
nor a module-partition implicitly imports the primary module interface unit of
the module as if by a module-import-declaration.
Implementation modules are never serialized (-emit-module-interface for an
implementation unit is diagnosed and rejected).
Differential Revision: https://reviews.llvm.org/D126959
This reverts commit c6e9823724ef6bdfee262289ee34d162db436af0.
Reason: Broke the ASan buildbots, see https://reviews.llvm.org/D126959
(the original phabricator review) for more info.
We need to be able to distinguish individual TUs from the same module in cases
where TU-local entities either need to be hidden (or, for some cases of ADL in
template instantiation, need to be detected as exposures).
This creates a module type for the implementation which implicitly imports its
primary module interface per C++20:
[module.unit/8] 'A module-declaration that contains neither an export-keyword
nor a module-partition implicitly imports the primary module interface unit of
the module as if by a module-import-declaration.
Implementation modules are never serialized (-emit-module-interface for an
implementation unit is diagnosed and rejected).
Differential Revision: https://reviews.llvm.org/D126959
This follows 2b4fa53 which made Clang not emit destructor calls for such
objects. However, they would still not get emitted as constants since
CodeGenModule::isTypeConstant() returns false if the destructor is
constexpr. This change adds a param to make isTypeConstant() ignore the
dtor, allowing the caller to check it instead.
Fixes Issue #61212
Differential revision: https://reviews.llvm.org/D145369
Previously we'll set the named modules for ASTContext in ParseAST. But
this is not intuitive and we need comments to tell the intuition. This
patch moves the code the right the place, where the corrresponding
module is first created/loaded. Now it is more intuitive and we can use
the value in the earlier places.
For the Itanium ABI, we emit an initializer for each module. This is responsible
for handling initialization of global vars. Relates to P1874R1.
The initializer has a known mangling and is automatically called from any TU that
imports a module. Since, at present, the importer has no way to determine that an
imported module does not require an initializer, we generate the initializer for
all cases (even when it is empty).
Initializers must be run once, with the ordering guaranteed by the import graph
and this is ensured in the current code by addition of a guard variable.
In the case that a module has no requirement for global initializers, and also does
not import any other modules, we can elide the guard variable.
Differential Revision: https://reviews.llvm.org/D134589
This value was added to clang/Basic in D111566, but is only used during
codegen, where we can use the LLVM IR DataLayout instead. I noticed this
because the downstream CHERI targets would have to also set this value
for AArch64/RISC-V/MIPS. Instead of duplicating more information between
LLVM IR and Clang, this patch moves getTargetAddressSpace(QualType T) to
CodeGenTypes, where we can consult the DataLayout.
Reviewed By: rjmccall
Differential Revision: https://reviews.llvm.org/D138296
This revision fixes typos where there are 2 consecutive words which are
duplicated. There should be no code changes in this revision (only
changes to comments and docs). Do let me know if there are any
undesirable changes in this revision. Thanks.
Fixes https://github.com/llvm/llvm-project/issues/55804
The lexing order is already bookkept in DelayedCXXInitPosition but we
were not using it based on the wrong assumption that inline variable is
unordered. This patch fixes it by ordering entries in llvm.global_ctors
by orders in DelayedCXXInitPosition.
for llvm.global_ctors entries without a lexing order, ordering them by
the insertion order.
(This *mostly* orders the template instantiation in
https://reviews.llvm.org/D126341 intuitively, minus one tweak for which I'll
submit a separate patch.)
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D127233
Currently we treat initializers with init_seg(compiler/lib) as similar
to any other init_seg, they simply have a global variable in the proper
section (".CRT$XCC" for compiler/".CRT$XCL" for lib) and are added to
llvm.used. However, this doesn't match with how LLVM sees normal (or
init_seg(user)) initializers via llvm.global_ctors. This
causes issues like incorrect init_seg(compiler) vs init_seg(user)
ordering due to GlobalOpt evaluating constructors, and the
ability to remove init_seg(compiler/lib) initializers at all.
Currently we use 'A' for priorities less than 200. Use 200 for
init_seg(compiler) (".CRT$XCC") and 400 for init_seg(lib) (".CRT$XCL"),
which do not append the priority to the section name. Priorities
between 200 and 400 use ".CRT$XCC${Priority}". This allows for
some wiggle room for people/future extensions that want to add
initializers between compiler and lib.
Fixes#56922
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D131910
Previously when we add module initializer, we forget to handle header
units. This results that we couldn't compile a Hello World Example with
Header Units. This patch tries to fix this.
Reviewed By: iains
Differential Revision: https://reviews.llvm.org/D130871
This reverts commit db6152ad66d7cf48f9f5c3eb28bf54c092978773.
This commit fails in ppc64. Since we want to backport it to 15.x. So
revert it now to keep the patch complete.
Previously when we add module initializer, we forget to handle header
units. This results that we couldn't compile a Hello World Example with
Header Units. This patch tries to fix this.
Reviewed By: iains
Differential Revision: https://reviews.llvm.org/D130871
HLSL Resource types need special annotations that the backend will use
to build out metadata and resource annotations that are required by
DirectX and Vulkan drivers in order to provide correct data bindings
for shader exeuction.
This patch adds some of the required data for unordered-access-views
(UAV) resource binding into the module flags. This data will evolve
over time to cover all the required use cases, but this should get
things started.
Depends on D130018.
Differential Revision: https://reviews.llvm.org/D130019
The re-land fixes module map module dependencies seen on Greendragon, but
not in the clang test suite.
---
Currently we only implement this for the Itanium ABI since the correct
mangling for the initializers in other ABIs is not yet known.
Intended result:
For a module interface [which includes partition interface and implementation
units] (instead of the generic CXX initializer) we emit a module init that:
- wraps the contained initializations in a control variable to ensure that
the inits only happen once, even if a module is imported many times by
imports of the main unit.
- calls module initializers for imported modules first. Note that the
order of module import is not significant, and therefore neither is the
order of imported module initializers.
- We then call initializers for the Global Module Fragment (if present)
- We then call initializers for the current module.
- We then call initializers for the Private Module Fragment (if present)
For a module implementation unit, or a non-module TU that imports at least one
module we emit a regular CXX init that:
- Calls the initializers for any imported modules first.
- Then proceeds as normal with remaining inits.
For all module unit kinds we include a global constructor entry, this allows
for the (in most cases unusual) possibility that a module object could be
included in a final binary without a specific call to its initializer.
Implementation:
- We provide the module pointer in the AST Context so that CodeGen can act
on it and its sub-modules.
- We need to account for module build lines like this:
` clang -cc1 -std=c++20 Foo.pcm -emit-obj -o Foo.o` or
` clang -cc1 -std=c++20 -xc++-module Foo.cpp -emit-obj -o Foo.o`
- in order to do this, we add to ParseAST to set the module pointer in
the ASTContext, once we establish that this is a module build and we
know the module pointer. To be able to do this, we make the query for
current module public in Sema.
- In CodeGen, we determine if the current build requires a CXX20-style module
init and, if so, we defer any module initializers during the "Eagerly
Emitted" phase.
- We then walk the module initializers at the end of the TU but before
emitting deferred inits (which adds any hidden and static ones, fixing
https://github.com/llvm/llvm-project/issues/51873 ).
- We then proceed to emit the deferred inits and continue to emit the CXX
init function.
Differential Revision: https://reviews.llvm.org/D126189
Currently we only implement this for the Itanium ABI since the correct
mangling for the initializers in other ABIs is not yet known.
Intended result:
For a module interface [which includes partition interface and implementation
units] (instead of the generic CXX initializer) we emit a module init that:
- wraps the contained initializations in a control variable to ensure that
the inits only happen once, even if a module is imported many times by
imports of the main unit.
- calls module initializers for imported modules first. Note that the
order of module import is not significant, and therefore neither is the
order of imported module initializers.
- We then call initializers for the Global Module Fragment (if present)
- We then call initializers for the current module.
- We then call initializers for the Private Module Fragment (if present)
For a module implementation unit, or a non-module TU that imports at least one
module we emit a regular CXX init that:
- Calls the initializers for any imported modules first.
- Then proceeds as normal with remaining inits.
For all module unit kinds we include a global constructor entry, this allows
for the (in most cases unusual) possibility that a module object could be
included in a final binary without a specific call to its initializer.
Implementation:
- We provide the module pointer in the AST Context so that CodeGen can act
on it and its sub-modules.
- We need to account for module build lines like this:
` clang -cc1 -std=c++20 Foo.pcm -emit-obj -o Foo.o` or
` clang -cc1 -std=c++20 -xc++-module Foo.cpp -emit-obj -o Foo.o`
- in order to do this, we add to ParseAST to set the module pointer in
the ASTContext, once we establish that this is a module build and we
know the module pointer. To be able to do this, we make the query for
current module public in Sema.
- In CodeGen, we determine if the current build requires a CXX20-style module
init and, if so, we defer any module initializers during the "Eagerly
Emitted" phase.
- We then walk the module initializers at the end of the TU but before
emitting deferred inits (which adds any hidden and static ones, fixing
https://github.com/llvm/llvm-project/issues/51873 ).
- We then proceed to emit the deferred inits and continue to emit the CXX
init function.
Differential Revision: https://reviews.llvm.org/D126189
Add option -fhip-kernel-arg-name to emit kernel argument
name metadata, which is needed for certain HIP applications.
Reviewed by: Artem Belevich, Fangrui Song, Brian Sumner
Differential Revision: https://reviews.llvm.org/D128022
Currently, enablement of heap MTE on Android is specified by an ELF note, which
signals to the linker to enable heap MTE. This change allows
-fsanitize=memtag-heap to synthesize these notes, rather than adding them
through the build system. We need to extend this feature to also signal the
linker to do special work for MTE globals (in future) and MTE stack (currently
implemented in the toolchain, but not implemented in the loader).
Current Android uses a non-backwards-compatible ELF note, called
".note.android.memtag". Stack MTE is an ABI break anyway, so we don't mind that
we won't be able to run executables with stack MTE on Android 11/12 devices.
The current expectation is to support the verbiage used by Android, in
that "SYNC" means MTE Synchronous mode, and "ASYNC" effectively means
"fast", using the Kernel auto-upgrade feature that allows
hardware-specific and core-specific configuration as to whether "ASYNC"
would end up being Asynchronous, Asymmetric, or Synchronous on that
particular core, whichever has a reasonable performance delta. Of
course, this is platform and loader-specific.
Differential Revision: https://reviews.llvm.org/D118948
The default construction of constructor functions by LLVM tends to make
them have internal linkage. When we call a ctor / dtor function in the
target region we are actually creating a kernel that is called at
registration. Because the ctor is a kernel we need to make sure it's
externally visible so we can actually call it. This prevented AMDGPU
from correctly using constructors while NVPTX could use them simply
because it ignored internal visibility.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D122504
When calling emitArrayDestroy(), the pointer will usually have
ConvertTypeForMem(EltType) as the element type, as one would expect.
However, globals with initializers sometimes don't use the same
types as values normally would, e.g. here the global uses
{ double, i32 } rather than %struct.T as element type.
Add an early cast to the global destruction path to avoid this
special case. The cast would happen lateron anyway, it only gets
moved to an earlier point.
Differential Revision: https://reviews.llvm.org/D116219
Change all uses of the deprecated constructor to pass the
element type explicitly and drop it.
For cases where the correct element type was not immediately
obvious to me or would require a slightly larger change I'm
falling back to explicitly calling getPointerElementType() for now.
Previously when emitting a C++ guarded initializer, we tried to work out what
the enclosing function would be used for and added it to the COMDAT containing
the variable if we thought that doing so would be correct. But this was done
from a context in which we didn't -- and realistically couldn't -- correctly
infer how the enclosing function would be used.
Instead, add the initialization function to a COMDAT from the code that
creates it, in the case where it makes sense to do so: when we know that
the one and only reference to the initialization function is in
@llvm.global.ctors and that reference is in the same COMDAT.
Reviewed By: rjmccall
Differential Revision: https://reviews.llvm.org/D108680
On ELF, an SHT_INIT_ARRAY outside a section group is a GC root. The current
codegen abuses SHT_INIT_ARRAY in a section group to mean a GC root.
On PE/COFF, the dynamic initialization for `__declspec(selectany)` in a comdat
can be garbage collected by `-opt:ref`.
Call `addUsedGlobal` for the two cases to fix the abuse/bug.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D106925
Summary:
The AIX linker will produce errors on unresolved weak symbols. Change the
generated code to not check for the initialization function but just call
it and ensure that it always exists. Also, the AIX atexit routine has a
different name (and signature) so call it correctly. Update the lit tests
to test on AIX appropriately.
Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: hubert.reinterpretcast (Hubert Tong)
Differential Revision: https://reviews.llvm.org/D104420
variables emitted on both host and device side with different addresses
when ODR-used by host function should not cause device side counter-part
to be force emitted.
This fixes the regression caused by https://reviews.llvm.org/D102237
Reviewed by: Artem Belevich
Differential Revision: https://reviews.llvm.org/D102801
