Instead use either Type::getPointerElementType() or
Type::getNonOpaquePointerElementType().
This is part of D117885, in preparation for deprecating the API.
TLS initializers, for example constructors of thread-local variables, don't necessarily get called. If a thread was created before a module is loaded, the module's TLS initializers are not executed for this particular thread.
This is why Microsoft added support for dynamic TLS initialization. Before every use of thread-local variables, a check is added that runs the module's TLS initializers on-demand.
To do this, the method `__dyn_tls_on_demand_init` gets called. Internally, it simply calls `__dyn_tls_init`.
No additional TLS initializer that sets the guard needs to be emitted, as the guard always gets set by `__dyn_tls_init`.
The guard is also checked again within `__dyn_tls_init`. This makes our check redundant, however, as Microsoft's compiler also emits this check, the behaviour is adopted here.
Reviewed By: majnemer
Differential Revision: https://reviews.llvm.org/D115456
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.
WG14 adopted the _ExtInt feature from Clang for C23, but renamed the
type to be _BitInt. This patch does the vast majority of the work to
rename _ExtInt to _BitInt, which accounts for most of its size. The new
type is exposed in older C modes and all C++ modes as a conforming
extension. However, there are functional changes worth calling out:
* Deprecates _ExtInt with a fix-it to help users migrate to _BitInt.
* Updates the mangling for the type.
* Updates the documentation and adds a release note to warn users what
is going on.
* Adds new diagnostics for use of _BitInt to call out when it's used as
a Clang extension or as a pre-C23 compatibility concern.
* Adds new tests for the new diagnostic behaviors.
I want to call out the ABI break specifically. We do not believe that
this break will cause a significant imposition for early adopters of
the feature, and so this is being done as a full break. If it turns out
there are critical uses where recompilation is not an option for some
reason, we can consider using ABI tags to ease the transition.
Currently, we have no front-end type for ppc_fp128 type in IR. PowerPC
target generates ppc_fp128 type from long double now, but there's option
(-mabi=(ieee|ibm)longdouble) to control it and we're going to do
transition from IBM extended double-double ppc_fp128 to IEEE fp128 in
the future.
This patch adds type __ibm128 which always represents ppc_fp128 in IR,
as what GCC did for that type. Without this type in Clang, compilation
will fail if compiling against future version of libstdcxx (which uses
__ibm128 in headers).
Although all operations in backend for __ibm128 is done by software,
only PowerPC enables support for it.
There's something not implemented in this commit, which can be done in
future ones:
- Literal suffix for __ibm128 type. w/W is suitable as GCC documented.
- __attribute__((mode(IF))) should be for __ibm128.
- Complex __ibm128 type.
Reviewed By: rjmccall
Differential Revision: https://reviews.llvm.org/D93377
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
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
Remove uses of to-be-deprecated API. In cases where the correct
element type was not immediately obvious to me, fall back to
explicit getPointerElementType().
Remove uses of to-be-deprecated API. I've fallen back to calling
getPointerElementType() in some cases where the correct type wasn't
immediately obvious to me.
In preparation for dropping support for it. I've replaced it with
a proper type where the correct type was obvious and left an
explicit getPointerElementType() where it wasn't.
functions implicitly generated by the compiler
These fake functions would cause clang to crash if the changes proposed
in https://reviews.llvm.org/D98799 were made.
As it was discovered in post-commit feedback
for 0aa0458f14,
we handle thunks incorrectly, and end up annotating
their this/return with attributes that are valid
for their callees, not for thunks themselves.
While it would be good to fix this properly,
and keep annotating them on thunks,
i've tried doing that in https://reviews.llvm.org/D100388
with little success, and the patch is stuck for a month now.
So for now, as a stopgap measure, subj.
This implements the flag proposed in RFC
http://lists.llvm.org/pipermail/cfe-dev/2020-August/066437.html.
The goal is to add a way to override the default target C++ ABI through a
compiler flag. This makes it easier to test and transition between different
C++ ABIs through compile flags rather than build flags.
In this patch:
- Store -fc++-abi= in a LangOpt. This isn't stored in a CodeGenOpt because
there are instances outside of codegen where Clang needs to know what the
ABI is (particularly through ASTContext::createCXXABI), and we should be
able to override the target default if the flag is provided at that point.
- Expose the existing ABIs in TargetCXXABI as values that can be passed
through this flag.
- Create a .def file for these ABIs to make it easier to check flag values.
- Add an error for diagnosing bad ABI flag values.
Differential Revision: https://reviews.llvm.org/D85802
The existing Windows Itanium patches for dllimport/export
behaviour w.r.t vtables/rtti can't be adopted for PS4 due to
backwards compatibility reasons (see comments on
https://reviews.llvm.org/D90299).
This commit adds our PS4 scheme for this to Clang.
Differential Revision: https://reviews.llvm.org/D93203
This removes some (but not all) uses of type-less CreateGEP()
and CreateInBoundsGEP() APIs, which are incompatible with opaque
pointers.
There are a still a number of tricky uses left, as well as many
more variation APIs for CreateGEP.
These are incompatible with opaque pointers. This is in preparation
of dropping this API on the IRBuilder side as well.
Instead explicitly pass the loaded type.
Background:
Wasm EH, while using Windows EH (catchpad/cleanuppad based) IR, uses
Itanium-based libraries and ABIs with some modifications.
`__clang_call_terminate` is a wrapper generated in Clang's Itanium C++
ABI implementation. It contains this code, in C-style pseudocode:
```
void __clang_call_terminate(void *exn) {
__cxa_begin_catch(exn);
std::terminate();
}
```
So this function is a wrapper to call `__cxa_begin_catch` on the
exception pointer before termination.
In Itanium ABI, this function is called when another exception is thrown
while processing an exception. The pointer for this second, violating
exception is passed as the argument of this `__clang_call_terminate`,
which calls `__cxa_begin_catch` with that pointer and calls
`std::terminate` to terminate the program.
The spec (https://libcxxabi.llvm.org/spec.html) for `__cxa_begin_catch`
says,
```
When the personality routine encounters a termination condition, it
will call __cxa_begin_catch() to mark the exception as handled and then
call terminate(), which shall not return to its caller.
```
In wasm EH's Clang implementation, this function is called from
cleanuppads that terminates the program, which we also call terminate
pads. Cleanuppads normally don't access the thrown exception and the
wasm backend converts them to `catch_all` blocks. But because we need
the exception pointer in this cleanuppad, we generate
`wasm.get.exception` intrinsic (which will eventually be lowered to
`catch` instruction) as we do in the catchpads. But because terminate
pads are cleanup pads and should run even when a foreign exception is
thrown, so what we have been doing is:
1. In `WebAssemblyLateEHPrepare::ensureSingleBBTermPads()`, we make sure
terminate pads are in this simple shape:
```
%exn = catch
call @__clang_call_terminate(%exn)
unreachable
```
2. In `WebAssemblyHandleEHTerminatePads` pass at the end of the
pipeline, we attach a `catch_all` to terminate pads, so they will be in
this form:
```
%exn = catch
call @__clang_call_terminate(%exn)
unreachable
catch_all
call @std::terminate()
unreachable
```
In `catch_all` part, we don't have the exception pointer, so we call
`std::terminate()` directly. The reason we ran HandleEHTerminatePads at
the end of the pipeline, separate from LateEHPrepare, was it was
convenient to assume there was only a single `catch` part per `try`
during CFGSort and CFGStackify.
---
Problem:
While it thinks terminate pads could have been possibly split or calls
to `__clang_call_terminate` could have been duplicated,
`WebAssemblyLateEHPrepare::ensureSingleBBTermPads()` assumes terminate
pads contain no more than calls to `__clang_call_terminate` and
`unreachable` instruction. I assumed that because in LLVM very limited
forms of transformations are done to catchpads and cleanuppads to
maintain the scoping structure. But it turned out to be incorrect;
passes can merge cleanuppads into one, including terminate pads, as long
as the new code has a correct scoping structure. One pass that does this
I observed was `SimplifyCFG`, but there can be more. After this
transformation, a single cleanuppad can contain any number of other
instructions with the call to `__clang_call_terminate` and can span many
BBs. It wouldn't be practical to duplicate all these BBs within the
cleanuppad to generate the equivalent `catch_all` blocks, only with
calls to `__clang_call_terminate` replaced by calls to `std::terminate`.
Unless we do more complicated transformation to split those calls to
`__clang_call_terminate` into a separate cleanuppad, it is tricky to
solve.
---
Solution (?):
This CL just disables the generation and use of `__clang_call_terminate`
and calls `std::terminate()` directly in its place.
The possible downside of this approach can be, because the Itanium ABI
intended to "mark" the violating exception handled, we don't do that
anymore. What `__cxa_begin_catch` actually does is increment the
exception's handler count and decrement the uncaught exception count,
which in my opinion do not matter much given that we are about to
terminate the program anyway. Also it does not affect info like stack
traces that can be possibly shown to developers.
And while we use a variant of Itanium EH ABI, we can make some
deviations if we choose to; we are already different in that in the
current version of the EH spec we don't support two-phase unwinding. We
can possibly consider a more complicated transformation later to
reenable this, but I don't think that has high priority.
Changes in this CL contains:
- In Clang, we don't generate a call to `wasm.get.exception()` intrinsic
and `__clang_call_terminate` function in terminate pads anymore; we
simply generate calls to `std::terminate()`, which is the default
implementation of `CGCXXABI::emitTerminateForUnexpectedException`.
- Remove `WebAssembly::ensureSingleBBTermPads() function and
`WebAssemblyHandleEHTerminatePads` pass, because terminate pads are
already `catch_all` now (because they don't need the exception
pointer) and we don't need these transformations anymore.
- Change tests to use `std::terminate` directly. Also removes tests that
tested `LateEHPrepare::ensureSingleBBTermPads` and
`HandleEHTerminatePads` pass.
- Drive-by fix: Add some function attributes to EH intrinsic
declarations
Fixes https://github.com/emscripten-core/emscripten/issues/13582.
Reviewed By: dschuff, tlively
Differential Revision: https://reviews.llvm.org/D97834
When WPD is enabled, via WholeProgramVTables, emit type metadata for
available_externally vtables. Additionally, add the vtables to the
llvm.compiler.used global so that they are not prematurely eliminated
(before *LTO analysis).
This is needed to avoid devirtualizing calls to a function overriding a
class defined in a header file but with a strong definition in a shared
library. Without type metadata on the available_externally vtables from
the header, the WPD analysis never sees what a derived class is
overriding. Even if the available_externally base class functions are
pure virtual, because shared library definitions are already treated
conservatively (committed patches D91583, D96721, and D96722) we will
not devirtualize, which would be unsafe since the library might contain
overrides that aren't visible to the LTO unit.
An example is std::error_category, which is overridden in LLVM
and causing failures after a self build with WPD enabled, because
libstdc++ contains hidden overrides of the virtual base class methods.
Differential Revision: https://reviews.llvm.org/D96919
Add the types for the RISC-V V extension builtins.
These types will be used by the RISC-V V intrinsics which require
types of the form <vscale x 1 x i64>(LMUL=1 element size=64) or
<vscale x 4 x i32>(LMUL=2 element size=32), etc. The vector_size
attribute does not work for us as it doesn't create a scalable
vector type. We want these types to be opaque and have no operators
defined for them. We want them to be sizeless. This makes them
similar to the ARM SVE builtin types. But we will have quite a bit
more types. This patch adds around 60. Later patches will add
another 230 or so types representing tuples of these types similar
to the x2/x3/x4 types in ARM SVE. But with extra complexity that
these types are combined with the LMUL concept that is unique to
RISCV.
For more background see this RFC
http://lists.llvm.org/pipermail/llvm-dev/2020-October/145850.html
Authored-by: Roger Ferrer Ibanez <roger.ferrer@bsc.es>
Co-Authored-by: Hsiangkai Wang <kai.wang@sifive.com>
Differential Revision: https://reviews.llvm.org/D92715
As Itanium ABI[http://itanium-cxx-abi.github.io/cxx-abi/abi.html#once-ctor]
points out:
"The size of the guard variable is 64 bits. The first byte (i.e. the byte at
the address of the full variable) shall contain the value 0 prior to
initialization of the associated variable, and 1 after initialization is complete."
Differential Revision: https://reviews.llvm.org/D95822
This patch enables the Clang type __vector_pair and its associated LLVM
intrinsics even when MMA is disabled. With this patch, the type is now controlled
by the PPC paired-vector-memops option. The builtins and intrinsics will be
renamed to drop the mma prefix in another patch.
Differential Revision: https://reviews.llvm.org/D91819
Sometimes people get minimal crash reports after a UBSAN incident. This change
tags each trap with an integer representing the kind of failure encountered,
which can aid in tracking down the root cause of the problem.
shouldRTTIBeUnique() returns false for iOS64CXXABI, which causes
RTTI objects to be emitted hidden. Update two tests that didn't
expect this to happen for the default triple.
Also rename iOS64CXXABI to AppleARM64CXXABI, since it's used for
arm64-apple-macos triples too.
Part of PR46644.
Differential Revision: https://reviews.llvm.org/D91904
This will ensure that passes that add new global variables will create them
in address space 1 once the passes have been updated to no longer default
to the implicit address space zero.
This also changes AutoUpgrade.cpp to add -G1 to the DataLayout if it wasn't
already to present to ensure bitcode backwards compatibility.
Reviewed by: arsenm
Differential Revision: https://reviews.llvm.org/D84345
mangling support for non-type template parameters of class type and
template parameter objects.
The Itanium side of this follows the approach I proposed in
https://github.com/itanium-cxx-abi/cxx-abi/issues/47 on 2020-09-06.
The MSVC side of this was determined empirically by observing MSVC's
output.
Differential Revision: https://reviews.llvm.org/D89998
Define the __vector_pair and __vector_quad types that are used to manipulate
the new accumulator registers introduced by MMA on PowerPC. Because these two
types are specific to PowerPC, they are defined in a separate new file so it
will be easier to add other PowerPC specific types if we need to in the future.
Differential Revision: https://reviews.llvm.org/D81508
Instead of framing the interface around whether the variable is an ICE
(which is only interesting in C++98), primarily track whether the
initializer is a constant initializer (which is interesting in all C++
language modes).
No functionality change intended.
for which it matters.
This is a step towards separating checking for a constant initializer
(in which std::is_constant_evaluated returns true) and any other
evaluation of a variable initializer (in which it returns false).
This reverts commits 683b308c07 and
8487bfd4e9.
We will go for a more restricted approach that does not give freedom to
everyone to change ABIs on whichever platform.
See the discussion on https://reviews.llvm.org/D85802.
This implements the flag proposed in RFC http://lists.llvm.org/pipermail/cfe-dev/2020-August/066437.html.
The goal is to add a way to override the default target C++ ABI through
a compiler flag. This makes it easier to test and transition between different
C++ ABIs through compile flags rather than build flags.
In this patch:
- Store `-fc++-abi=` in a LangOpt. This isn't stored in a
CodeGenOpt because there are instances outside of codegen where Clang
needs to know what the ABI is (particularly through
ASTContext::createCXXABI), and we should be able to override the
target default if the flag is provided at that point.
- Expose the existing ABIs in TargetCXXABI as values that can be passed
through this flag.
- Create a .def file for these ABIs to make it easier to check flag
values.
- Add an error for diagnosing bad ABI flag values.
Differential Revision: https://reviews.llvm.org/D85802
On some targets, preferred alignment is larger than ABI alignment in some cases. For example,
on AIX we have special power alignment rules which would cause that. Previously, to support
those cases, we added a “PreferredAlignment” field in the `RecordLayout` to store the AIX
special alignment values in “PreferredAlignment” as the community suggested.
However, that patch alone is not enough. There are places in the Clang where `PreferredAlignment`
should have been used instead of ABI-specified alignment. This patch is aimed at fixing those
spots.
Differential Revision: https://reviews.llvm.org/D86790
On the frontend side, this patch recovers AIX static init implementation to
use the linkage type and function names Clang chooses for sinit related function.
On the backend side, this patch sets correct linkage and function names on aliases
created for sinit/sterm functions.
Differential Revision: https://reviews.llvm.org/D84534
Set the debug location for static init related functions(__dtor
and __finalize) so we can generate valid debug info on AIX by invoking
-g with clang or -debug-info-kind=limited with clang_cc1.
This also works for any other future targets who may use sinit and
sterm functions for static initialization, where a direct call to
dtor will be generated within finalize function body.
This patch also aims at validating that the debug info generated
is correct for AIX sinit related functions.
Differential Revision: https://reviews.llvm.org/D83702
Adds `CodeGen::getCXXDestructorImplicitParam`, to retrieve a C++ destructor's implicit parameter (after the "this" pointer) based on the ABI in the given CodeGenModule.
This will allow other frontends (Swift, for example) to easily emit calls to object destructors with correct ABI semantics and calling convetions.
This is needed for Swift C++ interop. Here's the corresponding Swift change: https://github.com/apple/swift/pull/32291
Differential Revision: https://reviews.llvm.org/D82392
Arthur Eubanks