The previous patch introduced the offloading binary format so we can
store some metada along with the binary image. This patch introduces
using this inside the linker wrapper and Clang instead of the previous
method that embedded the metadata in the section name.
Differential Revision: https://reviews.llvm.org/D122683
This adds a PS5-specific ToolChain subclass, which defines some basic
PS5 driver behavior. Future patches will add more target-specific
driver behavior.
The current cc1 CLANG_ENABLE_OPAQUE_POINTERS=on default difference is not ideal
in that people contribute %clang_cc1 tests may assume the default ON behavior,
which will cause failures on systems set to OFF.
cc1 option default dependent on CMake options should be used prudently
(generally avoided). We prefer to limit target differences to Driver.
Change the CLANG_ENABLE_OPAQUE_POINTERS_INTERNAL mechanism introduced in D123122
to use a driver default instead. This is similar to the mechanism used for the
-flegacy-pass-manager transition to new PM transition.
Reviewed By: #opaque-pointers, rsmith, aeubanks
Differential Revision: https://reviews.llvm.org/D123744
This removes the -flegacy-pass-manager and
-fno-experimental-new-pass-manager options, and the corresponding
support code in BackendUtil. The -fno-legacy-pass-manager and
-fexperimental-new-pass-manager options are retained as no-ops.
Differential Revision: https://reviews.llvm.org/D123609
The Randstruct feature is a compile-time hardening technique that
randomizes the field layout for designated structures of a code base.
Admittedly, this is mostly useful for closed-source releases of code,
since the randomization seed would need to be available for public and
open source applications.
Why implement it? This patch set enhances Clang’s feature parity with
that of GCC which already has the Randstruct feature. It's used by the
Linux kernel in certain structures to help thwart attacks that depend on
structure layouts in memory.
This patch set is a from-scratch reimplementation of the Randstruct
feature that was originally ported to GCC. The patches for the GCC
implementation can be found here:
https://www.openwall.com/lists/kernel-hardening/2017/04/06/14
Link: https://lists.llvm.org/pipermail/cfe-dev/2019-March/061607.html
Co-authored-by: Cole Nixon <nixontcole@gmail.com>
Co-authored-by: Connor Kuehl <cipkuehl@gmail.com>
Co-authored-by: James Foster <jafosterja@gmail.com>
Co-authored-by: Jeff Takahashi <jeffrey.takahashi@gmail.com>
Co-authored-by: Jordan Cantrell <jordan.cantrell@mail.com>
Co-authored-by: Nikk Forbus <nicholas.forbus@gmail.com>
Co-authored-by: Tim Pugh <nwtpugh@gmail.com>
Co-authored-by: Bill Wendling <isanbard@gmail.com>
Signed-off-by: Bill Wendling <isanbard@gmail.com>
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D121556
This reverts commit 3f0587d0c6.
Not all tests pass after a few rounds of fixes.
I spot one failure that std::shuffle (potentially different results with
different STL implementations) was misused and replaced it with llvm::shuffle,
but there appears to be another failure in a Windows build.
The latest failure is reported on https://reviews.llvm.org/D121556#3440383
The Randstruct feature is a compile-time hardening technique that
randomizes the field layout for designated structures of a code base.
Admittedly, this is mostly useful for closed-source releases of code,
since the randomization seed would need to be available for public and
open source applications.
Why implement it? This patch set enhances Clang’s feature parity with
that of GCC which already has the Randstruct feature. It's used by the
Linux kernel in certain structures to help thwart attacks that depend on
structure layouts in memory.
This patch set is a from-scratch reimplementation of the Randstruct
feature that was originally ported to GCC. The patches for the GCC
implementation can be found here:
https://www.openwall.com/lists/kernel-hardening/2017/04/06/14
Link: https://lists.llvm.org/pipermail/cfe-dev/2019-March/061607.html
Co-authored-by: Cole Nixon <nixontcole@gmail.com>
Co-authored-by: Connor Kuehl <cipkuehl@gmail.com>
Co-authored-by: James Foster <jafosterja@gmail.com>
Co-authored-by: Jeff Takahashi <jeffrey.takahashi@gmail.com>
Co-authored-by: Jordan Cantrell <jordan.cantrell@mail.com>
Co-authored-by: Nikk Forbus <nicholas.forbus@gmail.com>
Co-authored-by: Tim Pugh <nwtpugh@gmail.com>
Co-authored-by: Bill Wendling <isanbard@gmail.com>
Signed-off-by: Bill Wendling <isanbard@gmail.com>
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D121556
Add CSKY target toolchains to support csky in linux and elf environment.
It can leverage the basic universal Linux toolchain for linux environment, and only add some compile or link parameters.
For elf environment, add a CSKYToolChain to support compile and link.
Also add some parameters into basic codebase of clang driver.
Differential Revision: https://reviews.llvm.org/D121445
Currently, clang-offload-bundler has -inputs and -outputs options that accept
values with comma as the delimiter. This causes issues with file paths
containing commas, which are valid file paths on Linux.
This add two new options -input and -output, which accept one single file,
and allow multiple instances. This allows arbitrary file paths. The old
-inputs and -outputs options will be kept for backward compatibility, but
are not allowed to be used with -input and -output options for simplicity.
In the future, -inputs and -outputs options will be phasing out.
RFC: https://discourse.llvm.org/t/rfc-adding-input-and-output-options-to-clang-offload-bundler/60049
Patch by: Siu Chi Chan
Reviewed by: Yaxun Liu
Differential Revision: https://reviews.llvm.org/D120662
While -g[no-]simple-template-names is a driver option, the fancier
-gsimple-template-names={simple,mangled} option is cc1-only, so code
to handle it in the driver is dead.
Differential Revision: https://reviews.llvm.org/D122503
Adds `--product-name=` flag to the clang driver. This gets forwarded to
cc1 only when we are performing a ExtractAPI Action. This is used to
populate the `name` field of the module object in the generated SymbolGraph.
Differential Revision: https://reviews.llvm.org/D122141
clang -extract-api should accept multiple headers and forward them to a
single CC1 instance. This change introduces a new ExtractAPIJobAction.
Currently API Extraction is done during the Precompile phase as this is
the current phase that matches the requirements the most. Adding a new
phase would need to change some logic in how phases are scheduled. If
the headers scheduled for API extraction are of different types the
driver emits a diagnostic.
Differential Revision: https://reviews.llvm.org/D121936
The NVPTX toolchain uses target features to determine the PTX version to
use. However this isn't exposed externally like most other toolchain
specific target features are. Add this functionaliy in preparation for
using it in for OpenMP offloading.
Reviewed By: jdoerfert, tra
Differential Revision: https://reviews.llvm.org/D122089
This patch adds the offload kind to the embedded section name in
preparation for offloading to different kinda like CUDA or HIP.
Depends on D120288
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D120271
This relands commit 7313474319.
It failed on Windows/Mac because `-fjmc` is only checked for ELF targets.
Check the flag unconditionally instead and issue a warning for non-ELF targets.
The motivation is to enable the MSVC-style JMC instrumentation usable by a ELF-based
debugger. Since there is no prior experience implementing JMC feature for ELF-based
debugger, it might be better to just reuse existing MSVC-style JMC instrumentation.
For debuggers that support both ELF&COFF (like lldb), the JMC implementation might
be shared between ELF&COFF. If this is found to inadequate, it is pretty low-cost
switching to alternatives.
Implementation:
- The '-fjmc' is already a driver and cc1 flag. Wire it up for ELF in the driver.
- Refactor the JMC instrumentation pass a little bit.
- The ELF handling is different from MSVC in two places:
* the flag section name is ".just.my.code" instead of ".msvcjmc"
* the way default function is provided: MSVC uses /alternatename; ELF uses weak function.
Based on D118428.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D119910
This new flag enables `__has_feature(cxx_unstable)` that would replace libc++ macros for individual unstable/experimental features, e.g. `_LIBCPP_HAS_NO_INCOMPLETE_RANGES` or `_LIBCPP_HAS_NO_INCOMPLETE_FORMAT`.
This would make it easier and more convenient to opt-in into all libc++ unstable features at once.
Differential Revision: https://reviews.llvm.org/D120160
Introduce -fgpu-default-stream={legacy|per-thread} option to
support per-thread default stream for HIP runtime.
When -fgpu-default-stream=per-thread, HIP kernels are
launched through hipLaunchKernel_spt instead of
hipLaunchKernel. Also HIP_API_PER_THREAD_DEFAULT_STREAM=1
is defined by the preprocessor to enable other per-thread stream
API's.
Reviewed by: Artem Belevich
Differential Revision: https://reviews.llvm.org/D120298
Currently when we generate OpenMP offloading code we always make
fallback code for the CPU. This is necessary for implementing features
like conditional offloading and ensuring that unhandled pragmas don't
result in missing symbols. However, this is problematic for a few cases.
For offloading tests we can silently fail to the host without realizing
that offloading failed. Additionally, this makes it impossible to
provide interoperabiility to other offloading schemes like HIP or CUDA
because those methods do not provide any such host fallback guaruntee.
this patch adds the `-fopenmp-offload-mandatory` flag to prevent
generating the fallback symbol on the CPU and instead replaces the
function with a dummy global and the failed branch with 'unreachable'.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D120353
The runtime uses thread state values to indicate when we use an ICV or
are in nested parallelism. This is done for OpenMP correctness, but it
not needed in the majority of cases. The new flag added is
`-fopenmp-assume-no-thread-state`.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D120106
This patch passes in the AMDPGU math libraries to the linker wrapper.
The wrapper already handles linking OpenMP bitcode libraries via the
`--target-library` option. This should be sufficient to link in math
libraries for the accompanying architecture.
Fixes#53526.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D119841
This patch passes in the AMDPGU math libraries to the linker wrapper.
The wrapper already handles linking OpenMP bitcode libraries via the
`--target-library` option. This should be sufficient to link in math
libraries for the accompanying architecture.
Fixes#53526.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D119841
This patch adds a new Darwin clang driver environment variable in the
spirit of RC_DEBUG_OPTIONS, called RC_DEBUG_PREFIX_MAP, which allows a
meta build tool to add one additional -fdebug-prefix-map entry without
the knowledge of the build system.
rdar://85224675
Differential Revision: https://reviews.llvm.org/D119850
This patch adds support for linking CPU offloading applications in the
linker wrapper. We generate the necessary linking job using the host
linker's path and library arguments. This may not be true for more
complex offloading schemes, but this is sufficient for now.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D119613
Now that the old device runtime has been deleted there is only a single
target that differs by the triple and the architecture. Simplify the
scheme for identifying the library but directly using the triple.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D119638
The introduction and some examples are on this page:
https://devblogs.microsoft.com/cppblog/announcing-jmc-stepping-in-visual-studio/
The `/JMC` flag enables these instrumentations:
- Insert at the beginning of every function immediately after the prologue with
a call to `void __fastcall __CheckForDebuggerJustMyCode(unsigned char *JMC_flag)`.
The argument for `__CheckForDebuggerJustMyCode` is the address of a boolean
global variable (the global variable is initialized to 1) with the name
convention `__<hash>_<filename>`. All such global variables are placed in
the `.msvcjmc` section.
- The `<hash>` part of `__<hash>_<filename>` has a one-to-one mapping
with a directory path. MSVC uses some unknown hashing function. Here I
used DJB.
- Add a dummy/empty COMDAT function `__JustMyCode_Default`.
- Add `/alternatename:__CheckForDebuggerJustMyCode=__JustMyCode_Default` link
option via ".drectve" section. This is to prevent failure in
case `__CheckForDebuggerJustMyCode` is not provided during linking.
Implementation:
All the instrumentations are implemented in an IR codegen pass. The pass is placed immediately before CodeGenPrepare pass. This is to not interfere with mid-end optimizations and make the instrumentation target-independent (I'm still working on an ELF port in a separate patch).
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D118428
code object version determines ABI, therefore should not be mixed.
This patch emits amdgpu_code_object_version module flag in LLVM IR
based on code object version (default 4).
The amdgpu_code_object_version value is code object version times 100.
LLVM IR with different amdgpu_code_object_version module flag cannot
be linked.
The -cc1 option -mcode-object-version=none is for ROCm device library use
only, which supports multiple ABI.
Reviewed by: Artem Belevich
Differential Revision: https://reviews.llvm.org/D119026
The "-fzero-call-used-regs" option tells the compiler to zero out
certain registers before the function returns. It's also available as a
function attribute: zero_call_used_regs.
The two upper categories are:
- "used": Zero out used registers.
- "all": Zero out all registers, whether used or not.
The individual options are:
- "skip": Don't zero out any registers. This is the default.
- "used": Zero out all used registers.
- "used-arg": Zero out used registers that are used for arguments.
- "used-gpr": Zero out used registers that are GPRs.
- "used-gpr-arg": Zero out used GPRs that are used as arguments.
- "all": Zero out all registers.
- "all-arg": Zero out all registers used for arguments.
- "all-gpr": Zero out all GPRs.
- "all-gpr-arg": Zero out all GPRs used for arguments.
This is used to help mitigate Return-Oriented Programming exploits.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D110869
The original warning added in D115501 when pacbti is used with an
incompatible architecture was not exactly correct because it was
not really ignored and can affect codegen.
Therefore reword to say that the pacbti option is incompatible with
the given architecture.
Reviewed By: chill
Differential Revision: https://reviews.llvm.org/D119166
AArch32/Armv8A introduced the performance deprecation of certain patterns
of IT instructions. After some debate internal to ARM, this is now being
reverted; i.e. no IT instruction patterns are performance deprecated
anymore, as the perfomance degredation is not significant enough.
This reverts the following:
"ARMv8-A deprecates some uses of the T32 IT instruction. All uses of
IT that apply to instructions other than a single subsequent 16-bit
instruction from a restricted set are deprecated, as are explicit
references to the PC within that single 16-bit instruction. This permits
the non-deprecated forms of IT and subsequent instructions to be treated
as a single 32-bit conditional instruction."
The deprecation no longer applies, but the behaviour may be controlled
by the -arm-restrict-it and -arm-no-restrict-it command-line options,
with the latter being the default. No warnings about complex IT blocks
will be generated.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D118044
This patch completely removes the old OpenMP device runtime. Previously,
the old runtime had the prefix `libomptarget-new-` and the old runtime
was simply called `libomptarget-`. This patch makes the formerly new
runtime the only runtime available. The entire project has been deleted,
and all references to the `libomptarget-new` runtime has been replaced
with `libomptarget-`.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D118934
The linker wrapper tool uses the 'nvlink' and 'ptxas' binaries to link
and assemble device files. Previously we searched for this using the
binaries in the user's path. This didn't work in cases where the user
passed in a specific Cuda path to Clang. This patch changes the linker
wrapper to accept an argument for the Cuda path we can get from Clang.
This should fix#53573.
Reviewed By: tianshilei1992
Differential Revision: https://reviews.llvm.org/D118944
Summary:
This patch implements the `-save-temps` flag for the linker wrapper.
This allows the user to inspect the intermeditary outpout that the
linker wrapper creates.
This patch adds support for a few extra flags in the linker wrapper,
such as debugging flags, verbose output, and passing arguments to ptxas. We also
now forward pass remarks to the LLVM backend so they will show up in the LTO
passes.
Depends on D117049
Differential Revision: https://reviews.llvm.org/D117156
Summary;
This patch adds support for embedding device images in the linker
wrapper tool. This will be used for performing JIT functionality in the
future.
Depends on D117048
Differential Revision: https://reviews.llvm.org/D117049
Summary:
This patch adds support for linking the OpenMP device bitcode library
late when doing LTO. This simply passes it in as an additional device
file when doing the final device linking phase with LTO. This has the
advantage that we don't link it multiple times, and the device
references do not get inlined and prevent us from doing needed OpenMP
optimizations when we have visiblity of the whole module.
Fix some failings where the implicit conversion of an Error to an
Expected triggered the deleted copy constructor.
Depends on D116675
Differential revision: https://reviews.llvm.org/D117048
This patch implements the fist support for handling LTO in the
offloading pipeline. The flag `-foffload-lto` is used to control if
bitcode is embedded into the device. If bitcode is found in the device,
the extracted files will be sent to the LTO pipeline to be linked and
sent to the backend. This implementation does not separately link the
device bitcode libraries yet.
Depends on D116675
Differential Revision: https://reviews.llvm.org/D116975
This patch introduces a linker wrapper tool that allows us to preprocess
files before they are sent to the linker. This adds a dummy action and
job to the driver stage that builds the linker command as usual and then
replaces the command line with the wrapper tool.
Depends on D116543
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D116544
This patch adds support for embedding the device object files into the
host IR to create a fat binary. Each offloading file will be inserted
into a section with the following naming format
`.llvm.offloading.<triple>.<arch>.<filename>`.
Depends on D116542
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D116543
This patch introduces the `-fopenmp-new-driver` option which instructs
the compiler to use a new driver scheme for producing offloading code.
In this scheme we create a complete offloading object file and then pass
it as input to the host compilation phase. This will allow us to embed
the object code in the backend phase.
This is the start of a series of commits to rework the OpenMP offloading driver
pipeline. The goal of this is to simplify the steps required for creating an
offloading program. This patch changes the driver's configuration to simply pass
the device file back to the host as an input so it can be embedded as an LLVM IR
global during the backend, then simply passes that object file to the linker.
This driver implementation will currently create the following phases,
```
$ clang input.c -fopenmp -fopenmp-targets=nvptx64 -fopenmp-new-driver -ccc-print-phases
+- 0: input, "input.c", c, (host-openmp)
+- 1: preprocessor, {0}, cpp-output, (host-openmp)
+- 2: compiler, {1}, ir, (host-openmp)
| | +- 3: input, "input.c", c, (device-openmp)
| | +- 4: preprocessor, {3}, cpp-output, (device-openmp)
| |- 5: compiler, {4}, ir, (device-openmp)
| +- 6: offload, "host-openmp (x86_64-unknown-linux-gnu)" {2}, "device-openmp (nvptx64)" {5}, ir
| +- 7: backend, {6}, assembler, (device-openmp)
|- 8: assembler, {7}, object, (device-openmp)
+- 9: offload, "host-openmp (x86_64-unknown-linux-gnu)" {2}, "device-openmp (nvptx64)" {8}, ir
+- 10: backend, {9}, assembler, (host-openmp)
+- 11: assembler, {10}, object, (host-openmp)
12: clang-linker-wrapper, {11}, image, (host-openmp)
```
Which will map to the following bindings
```
# "x86_64-unknown-linux-gnu" - "clang", inputs: ["input.c"], output: "/tmp/input-bae62e.bc"
# "nvptx64" - "clang", inputs: ["input.c", "/tmp/input-bae62e.bc"], output: "/tmp/input-76784e.s"
# "nvptx64" - "NVPTX::Assembler", inputs: ["/tmp/input-76784e.s"], output: "/tmp/input-8f29db.o"
# "x86_64-unknown-linux-gnu" - "clang", inputs: ["/tmp/input-bae62e.bc", "/tmp/input-8f29db.o"], output: "/tmp/input-545450.o"
# "x86_64-unknown-linux-gnu" - "Offload::Linker", inputs: ["/tmp/input-545450.o"], output: "a.out"
```
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D116541
Branch protection in M-class is supported by
- Armv8.1-M.Main
- Armv8-M.Main
- Armv7-M
Attempting to enable this for other architectures, either by
command-line (e.g -mbranch-protection=bti) or by target attribute
in source code (e.g. __attribute__((target("branch-protection=..."))) )
will generate a warning.
In both cases function attributes related to branch protection will not
be emitted. Regardless of the warning, module level attributes related to
branch protection will be emitted when it is enabled via the command-line.
The following people also contributed to this patch:
- Victor Campos
Reviewed By: chill
Differential Revision: https://reviews.llvm.org/D115501
GCC added -gz=zlib-gnu in 2014 for -gz meaning change (.zdebug =>
SHF_COMPRESSED) and the legacy zlib-gnu hasn't gain adoption.
According to Debian Code Search (`gz=zlib-gnu`), no project uses -gz=zlib-gnu
(valgrind has a configure to use -gz=zlib). Any possible -gz=zlib-gnu user can
switch to -gz smoothly (supported by integrated assemblers for many years;
binutils 2.26).
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D117744
This method introduces new CMake variable
PPC_LINUX_DEFAULT_IEEELONGDOUBLE (false by default) to enable fp128 as
default long double format.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D118110
Intel's CET/IBT requires every indirect branch target to be an ENDBR instruction. Because of that, the compiler needs to correctly emit these instruction on function's prologues. Because this is a security feature, it is desirable that only actual indirect-branch-targeted functions are emitted with ENDBRs. While it is possible to identify address-taken functions through LTO, minimizing these ENDBR instructions remains a hard task for user-space binaries because exported functions may end being reachable through PLT entries, that will use an indirect branch for such. Because this cannot be determined during compilation-time, the compiler currently emits ENDBRs to every non-local-linkage function.
Despite the challenge presented for user-space, the kernel landscape is different as no PLTs are used. With the intent of providing the most fit ENDBR emission for the kernel, kernel developers proposed an optimization named "ibt-seal" which replaces the ENDBRs for NOPs directly in the binary. The discussion of this feature can be seen in [1].
This diff brings the enablement of the flag -mibt-seal, which in combination with LTO enforces a different policy for ENDBR placement in when the code-model is set to "kernel". In this scenario, the compiler will only emit ENDBRs to address taken functions, ignoring non-address taken functions that are don't have local linkage.
A comparison between an LTO-compiled kernel binaries without and with the -mibt-seal feature enabled shows that when -mibt-seal was used, the number of ENDBRs in the vmlinux.o binary patched by objtool decreased from 44383 to 33192, and that the number of superfluous ENDBR instructions nopped-out decreased from 11730 to 540.
The 540 missed superfluous ENDBRs need to be investigated further, but hypotheses are: assembly code not being taken care of by the compiler, kernel exported symbols mechanisms creating bogus address taken situations or even these being removed due to other binary optimizations like kernel's static_calls. For now, I assume that the large drop in the number of ENDBR instructions already justifies the feature being merged.
[1] - https://lkml.org/lkml/2021/11/22/591
Reviewed By: xiangzhangllvm
Differential Revision: https://reviews.llvm.org/D116070
This patch changes the special-case handling of visibility when
compiling for an OpenMP target offloading device. This was orignally
added as a precaution against the bug encountered in PR41826 when
symbols in the device were being preempted by shared library symbols.
This should instead be done by making the visibility protected by default.
With protected visibility we are asserting that the symbols on the device
will never be preempted or preempt another symbol pending a shared library
load.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D117806
This patch adds support for the MSVC /HOTPATCH flag: https://docs.microsoft.com/sv-se/cpp/build/reference/hotpatch-create-hotpatchable-image?view=msvc-170&viewFallbackFrom=vs-2019
The flag is translated to a new -fms-hotpatch flag, which in turn adds a 'patchable-function' attribute for each function in the TU. This is then picked up by the PatchableFunction pass which would generate a TargetOpcode::PATCHABLE_OP of minsize = 2 (which means the target instruction must resolve to at least two bytes). TargetOpcode::PATCHABLE_OP is only implemented for x86/x64. When targetting ARM/ARM64, /HOTPATCH isn't required (instructions are always 2/4 bytes and suitable for hotpatching).
Additionally, when using /Z7, we generate a 'hot patchable' flag in the CodeView debug stream, in the S_COMPILE3 record. This flag is then picked up by LLD (or link.exe) and is used in conjunction with the linker /FUNCTIONPADMIN flag to generate extra space before each function, to accommodate for live patching long jumps. Please see: d703b92296/lld/COFF/Writer.cpp (L1298)
The outcome is that we can finally use Live++ or Recode along with clang-cl.
NOTE: It seems that MSVC cl.exe always enables /HOTPATCH on x64 by default, although if we did the same I thought we might generate sub-optimal code (if this flag was active by default). Additionally, MSVC always generates a .debug$S section and a S_COMPILE3 record, which Clang doesn't do without /Z7. Therefore, the following MSVC command-line "cl /c file.cpp" would have to be written with Clang such as "clang-cl /c file.cpp /HOTPATCH /Z7" in order to obtain the same result.
Depends on D43002, D80833 and D81301 for the full feature.
Differential Revision: https://reviews.llvm.org/D116511
This was intended to be fixed by D98856, but that only seemed to have
the desired behaviour when compiling to assembly using `-S`, not when
compiling into an object file or executable. Given that this was not
the intention of D98856, this patch fixes the behaviour.
Added warning for potential cases of
unaligned access when option
-mno-unaligned-access has been specified
Differential Revision: https://reviews.llvm.org/D116221
Early revisions of the VR4300 have a hardware bug where two consecutive
multiplications can produce an incorrect result in the second multiply.
This revision adds the `-mfix4300` flag to llvm (and clang) which, when
passed, provides a software fix for this issue.
More precise description of the "mulmul" bug:
```
mul.[s,d] fd,fs,ft
mul.[s,d] fd,fs,ft or [D]MULT[U] rs,rt
```
When the above sequence is executed by the CPU, if at least one of the
source operands of the first mul instruction happens to be `sNaN`, `0`
or `Infinity`, then the second mul instruction may produce an incorrect
result. This can happen both if the two mul instructions are next to each
other and if the first one is in a delay slot and the second is the first
instruction of the branch target.
Description of the fix:
This fix adds a backend pass to llvm which scans for mul instructions in
each basic block and inserts a nop whenever the following conditions are
met:
- The current instruction is a single or double-precision floating-point
mul instruction.
- The next instruction is either a mul instruction (any kind) or a branch
instruction.
Differential Revision: https://reviews.llvm.org/D116238
The Linux kernel has a make macro called cc-option that invokes the
compiler with an option in isolation to see if it is supported before
adding it to CFLAGS. The exit code of the compiler is used to determine
if the flag is supported and should be added to the compiler invocation.
A call to cc-option with '-mno-outline-atomics' was added to prevent
linking errors with newer GCC versions but this call succeeds with a
non-AArch64 target because there is no warning from clang with
'-mno-outline-atomics', just '-moutline-atomics'. Because the call
succeeds and adds '-mno-outline-atomics' to the compiler invocation,
there is a warning from LLVM because the 'outline-atomics target
feature is only supported by the AArch64 backend.
$ echo | clang -target x86_64 -moutline-atomics -Werror -x c -c -o /dev/null -
clang-14: error: The 'x86_64' architecture does not support -moutline-atomics; flag ignored [-Werror,-Woption-ignored]
$ echo $?
1
$ echo | clang -target x86_64 -mno-outline-atomics -Werror -x c -c -o /dev/null -
'-outline-atomics' is not a recognized feature for this target (ignoring feature)
$ echo $?
0
This does not match GCC's behavior, which errors when the flag is added
to a non-AArch64 target.
$ echo | gcc -moutline-atomics -x c -c -o /dev/null -
gcc: error: unrecognized command-line option ‘-moutline-atomics’; did you mean ‘-finline-atomics’?
$ echo | gcc -mno-outline-atomics -x c -c -o /dev/null -
gcc: error: unrecognized command-line option ‘-mno-outline-atomics’; did you mean ‘-fno-inline-atomics’?
$ echo | aarch64-linux-gnu-gcc -moutline-atomics -x c -c -o /dev/null -
$ echo | aarch64-linux-gnu-gcc -mno-outline-atomics -x c -c -o /dev/null -
To get closer to GCC's behavior, issue a warning when
'-mno-outline-atomics' is used without an AArch64 triple and do not add
'{-,+}outline-atomic" to the list of target features in these cases.
Link: https://github.com/ClangBuiltLinux/linux/issues/1552
Reviewed By: melver, nickdesaulniers
Differential Revision: https://reviews.llvm.org/D116128
This patch adds a toolchain (TC) for SPIR-V along with the
following changes in Driver and base ToolChain and Tool.
This is required to provide a mechanism in clang to bypass
SPIR-V backend in LLVM for SPIR-V until it lands in LLVM and
matures.
The SPIR-V code is generated by the SPIRV-LLVM translator tool
named 'llvm-spirv' that is sought in 'PATH'.
The compilation phases/actions should be bound for SPIR-V in
the meantime as following:
compile -> tools::Clang
backend -> tools::SPIRV::Translator
assemble -> tools::SPIRV::Translator
However, Driver’s ToolSelector collapses compile-backend-assemble
and compile-backend sequences to tools::Clang. To prevent this,
added new {use,has}IntegratedBackend properties in ToolChain and
Tool to which the ToolSelector reacts on, and which SPIR-V TC
overrides.
Linking of multiple input files is currently not supported but
can be added separately.
Differential Revision: https://reviews.llvm.org/D112410
Co-authored-by: Henry Linjamäki <henry.linjamaki@parmance.com>
Reland integrates build fixes & further review suggestions.
Thanks to @zturner for the initial S_OBJNAME patch!
Differential Revision: https://reviews.llvm.org/D43002
Also revert all subsequent fixes:
- abd1cbf5e5 [Clang] Disable debug-info-objname.cpp test on Unix until I sort out the issue.
- 00ec441253 [Clang] debug-info-objname.cpp test: explictly encode a x86 target when using %clang_cl to avoid falling back to a native CPU triple.
- cd407f6e52 [Clang] Fix build by restricting debug-info-objname.cpp test to x86.
This patch refactors the HIP tool chain for new HIP tool chain, HIPSPV
tool chain, which is added in the follow up patch part 2.
Rename HIPToolChain to HIPAMDToolChain and Renames HIP.* files to HIPAMD.*.
Introduce HIPUtility.* file where common HIP utilities, shared among HIP
tool chain implementations, are placed in.
Move constructHIPFatbinCommand() and
constructGenerateObjFileFromHIPFatBinary() to HIPUtility. HIPSPV tool
chain is going to use them.
Tweak bundle target ID in constructHIPFatbinCommand(): extra dashes are
dropped if the Target ID is empty and 'hip' offload kind is made default
for non-AMD targets.
Patch by: Henry Linjamäki
Reviewed by: Yaxun Liu, Artem Belevich, Eric Christopher
Differential Revision: https://reviews.llvm.org/D110549
When this pass was originally implemented, the fix pass was enabled
using a llvm command-line flag. This works fine, except in the case of
LTO, where the flag is not passed into the linker plugin in order to
enable the function pass in the LTO backend.
Now LTO exists, the expectation now is to use target features rather
than command-line arguments to control code generation, as this ensures
that different command-line arguments in different files are correctly
represented, and target-features always get to the LTO plugin as they
are encoded into LLVM IR.
The fall-out of this change is that the fix pass has to always be added
to the backend pass pipeline, so now it makes no changes if the function
does not have the right target feature to enable it. This should make a
minimal difference to compile time.
One advantage is it's now much easier to enable when compiling for a
Cortex-A53, as CPUs imply their own individual sets of target-features,
in a more fine-grained way. I haven't done this yet, but it is an
option, if the fix should be enabled in more places.
Existing tests of the user interface are unaffected, the changes are to
reflect that the argument is now turned into a target feature.
Reviewed By: tmatheson
Differential Revision: https://reviews.llvm.org/D114703
The new runtime is currently broken for AMD offloading. This patch makes
the default the old runtime only for the AMD target.
Reviewed By: ronlieb
Differential Revision: https://reviews.llvm.org/D114965
This patch changes the `-fopenmp-target-new-runtime` option which controls if
the new or old device runtime is used to be true by default. Disabling this to
use the old runtime now requires using `-fno-openmp-target-new-runtime`.
Reviewed By: JonChesterfield, tianshilei1992, gregrodgers, ronlieb
Differential Revision: https://reviews.llvm.org/D114890
Handle branch protection option on the commandline as well as a function
attribute. One patch for both mechanisms, as they use the same underlying
parsing mechanism.
These are recorded in a set of LLVM IR module-level attributes like we do for
AArch64 PAC/BTI (see https://reviews.llvm.org/D85649):
- command-line options are "translated" to module-level LLVM IR
attributes (metadata).
- functions have PAC/BTI specific attributes iff the
__attribute__((target("branch-protection=...))) was used in the function
declaration.
- command-line option -mbranch-protection to armclang targeting Arm,
following this grammar:
branch-protection ::= "-mbranch-protection=" <protection>
protection ::= "none" | "standard" | "bti" [ "+" <pac-ret-clause> ]
| <pac-ret-clause> [ "+" "bti"]
pac-ret-clause ::= "pac-ret" [ "+" <pac-ret-option> ]
pac-ret-option ::= "leaf" ["+" "b-key"] | "b-key" ["+" "leaf"]
b-key is simply a placeholder to make it consistent with AArch64's
version. In Arm, however, it triggers a warning informing that b-key is
unsupported and a-key will be selected instead.
- Handle _attribute_((target(("branch-protection=..."))) for AArch32 with the
same grammer as the commandline options.
This patch is part of a series that adds support for the PACBTI-M extension of
the Armv8.1-M architecture, as detailed here:
https://community.arm.com/arm-community-blogs/b/architectures-and-processors-blog/posts/armv8-1-m-pointer-authentication-and-branch-target-identification-extension
The PACBTI-M specification can be found in the Armv8-M Architecture Reference
Manual:
https://developer.arm.com/documentation/ddi0553/latest
The following people contributed to this patch:
- Momchil Velikov
- Victor Campos
- Ties Stuij
Reviewed By: vhscampos
Differential Revision: https://reviews.llvm.org/D112421
Allow toggling of -fnew-infallible so last instance takes precedence
Testing:
ninja check-all
Reviewed By: bruno
Differential Revision: https://reviews.llvm.org/D113523
[NFC] As part of using inclusive language within the llvm project, this patch
renames master flag to main flag in these comments.
Reviewed By: ZarkoCA
Differential Revision: https://reviews.llvm.org/D114090
From GCC's manpage:
-fplugin-arg-name-key=value
Define an argument called key with a value of value for the
plugin called name.
Since we don't have a key-value pair similar to gcc's plugin_argument
struct, simply accept key=value here anyway and pass it along as-is to
plugins.
This translates to the already existing '-plugin-arg-pluginname arg'
that clang cc1 accepts.
There is an ambiguity here because in clang, both the plugin name
as well as the option name can contain dashes, so when e.g. passing
-fplugin-arg-foo-bar-foo
it is not clear whether the plugin is foo-bar and the option is foo,
or the plugin is foo and the option is bar-foo. GCC solves this by
interpreting all dashes as part of the option name. So dashes can't be
part of the plugin name in this case.
Differential Revision: https://reviews.llvm.org/D113250
AMD64 ABI mandates caller to specify the number of used SSE registers
when passing variable arguments.
GCC also provides option -mskip-rax-setup to skip the setup of rax when
SSE is disabled. This helps to reduce the code size, see pr23258.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D112413
ld.lld used by Android ignores .note.GNU-stack and defaults to noexecstack,
so the `-z noexecstack` linker option is unneeded.
The `--noexecstack` assembler option is unneeded because AsmPrinter.cpp
prints `.section .note.GNU-stack,"",@progbits` (when `llvm.init.trampoline` is unused),
so the assembler won't synthesize an executable .note.GNU-stack.
Reviewed By: danalbert
Differential Revision: https://reviews.llvm.org/D113840
With this,
void f() { __asm__("mov eax, ebx"); }
now compiles with clang with -masm=intel.
This matches gcc.
The flag is not accepted in clang-cl mode. It has no effect on
MSVC-style `__asm {}` blocks, which are unconditionally in intel
mode both before and after this change.
One difference to gcc is that in clang, inline asm strings are
"local" while they're "global" in gcc. Building the following with
-masm=intel works with clang, but not with gcc where the ".att_syntax"
from the 2nd __asm__() is in effect until file end (or until a
".intel_syntax" somewhere later in the file):
__asm__("mov eax, ebx");
__asm__(".att_syntax\nmovl %ebx, %eax");
__asm__("mov eax, ebx");
This also updates clang's intrinsic headers to work both in
-masm=att (the default) and -masm=intel modes.
The official solution for this according to "Multiple assembler dialects in asm
templates" in gcc docs->Extensions->Inline Assembly->Extended Asm
is to write every inline asm snippet twice:
bt{l %[Offset],%[Base] | %[Base],%[Offset]}
This works in LLVM after D113932 and D113894, so use that.
(Just putting `.att_syntax` at the start of the snippet works in some but not
all cases: When LLVM interpolates in parameters like `%0`, it uses at&t or
intel syntax according to the inline asm snippet's flavor, so the `.att_syntax`
within the snippet happens to late: The interpolated-in parameter is already
in intel style, and then won't parse in the switched `.att_syntax`.)
It might be nice to invent a `#pragma clang asm_dialect push "att"` /
`#pragma clang asm_dialect pop` to be able to force asm style per snippet,
so that the inline asm string doesn't contain the same code in two variants,
but let's leave that for a follow-up.
Fixes PR21401 and PR20241.
Differential Revision: https://reviews.llvm.org/D113707
Change the error message to use ignorelist, and changed some variable and function
names in related code and test.
Reviewed By: thakis
Differential Revision: https://reviews.llvm.org/D113189
The driver uses class SanitizerArgs to store parsed sanitizer arguments. It keeps a cached
SanitizerArgs object in ToolChain and uses it for different jobs. This does not work if
the sanitizer options are different for different jobs, which could happen when an
offloading toolchain translates the options for different jobs.
To fix this, SanitizerArgs should be created by using the actual arguments passed
to jobs instead of the original arguments passed to the driver, since the toolchain
may change the original arguments. And the sanitizer arguments should be diagnose
once.
This patch also fixes HIP toolchain for handling -fgpu-sanitize: a warning is emitted
for GPU's not supporting sanitizer and skipped. This is for backward compatibility
with existing -fsanitize options. -fgpu-sanitize is also turned on by default.
Reviewed by: Artem Belevich, Evgenii Stepanov
Differential Revision: https://reviews.llvm.org/D111443
Implement support for loading the stack canary from a memory location held in
the TLS register, with an optional offset applied. This is used by the Linux
kernel to implement per-task stack canaries, which is impossible on SMP systems
when using a global variable for the stack canary.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D112768
Add new triple and target info for ‘spirv32’ and ‘spirv64’ and,
thus, enabling clang (LLVM IR) code emission to SPIR-V target.
The target for SPIR-V is mostly reused from SPIR by derivation
from a common base class since IR output for SPIR-V is mostly
the same as SPIR. Some refactoring are made accordingly.
Added and updated tests for parts that are different between
SPIR and SPIR-V.
Patch by linjamaki (Henry Linjamäki)!
Differential Revision: https://reviews.llvm.org/D109144
Trying to update some options that don't at least have an inclusive language version.
This patch adds `objcmt-allowlist-dir-path` as a default alternative.
Reviewed By: akyrtzi
Differential Revision: https://reviews.llvm.org/D112591
This reverts commit 2d7fba5f95.
The patch was reverted because it caused regression with rocThrust
due to ambiguity of template specialization.
For details please see https://reviews.llvm.org/D109496
A resolution to the ambiguity issues created by P0522, which is a DR solving
CWG 150, did not come as expected, so we are just going to accept the change,
and watch how users digest it.
For now we deprecate the flag with a warning, and make it on by default.
We don't remove the flag completely in order to give users a chance to
work around any problems by disabling it.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D109496
This patch splits the existing SveVectorBits LangOpt into VScaleMin and
VScaleMax LangOpts such that we can represent such an option. The cc1
option has also been split into -mvscale-{min,max}=<n> options so that the
cc1 arguments better reflect the vscale_range IR attribute.
Differential Revision: https://reviews.llvm.org/D111790
Representation of the file's last modification time depends on the file
system and isn't guaranteed to be in seconds. Cast to seconds explicitly
and tighten the test case to check the magnitude of the calculated
value, so we can catch passing milliseconds or nanoseconds.
rdar://83915615
Differential Revision: https://reviews.llvm.org/D111205
This patch ensures that we always tune for a given CPU on AArch64
targets when the user specifies the "-mtune=xyz" flag. In the
AArch64Subtarget if the tune flag is unset we use the CPU value
instead.
I've updated the release notes here:
llvm/docs/ReleaseNotes.rst
and added tests here:
clang/test/Driver/aarch64-mtune.c
Differential Revision: https://reviews.llvm.org/D110258
By default clang emits complete contructors as alias of base constructors if they are the same.
The backend is supposed to emit symbols for the alias, otherwise it causes undefined symbols.
@yaxunl observed that this issue is related to the llvm options `-amdgpu-early-inline-all=true`
and `-amdgpu-function-calls=false`. This issue is resolved by only inlining global values
with internal linkage. The `getCalleeFunction()` in AMDGPUResourceUsageAnalysis also had
to be extended to support aliases to functions. inline-calls.ll was corrected appropriately.
Reviewed By: yaxunl, #amdgpu
Differential Revision: https://reviews.llvm.org/D109707
By default clang emits complete contructors as alias of base constructors if they are the same.
The backend is supposed to emit symbols for the alias, otherwise it causes undefined symbols.
@yaxunl observed that this issue is related to the llvm options `-amdgpu-early-inline-all=true`
and `-amdgpu-function-calls=false`. This issue is resolved by only inlining global values
with internal linkage. The `getCalleeFunction()` in AMDGPUResourceUsageAnalysis also had
to be extended to support aliases to functions. inline-calls.ll was corrected appropriately.
Reviewed By: yaxunl, #amdgpu
Differential Revision: https://reviews.llvm.org/D109707
This reland commit 1131b1eb35, which
adds support to __attribute__((availability)) annotation for Fuchsia
platform. This patch also adds '-ffuchsia-api-level' to allow specify
Fuchsia API level from the command line.
Differential Revision: https://reviews.llvm.org/D108592
This patch adds support to __attribute__((availability)) annotation for
Fuchsia platform. This patch also adds '-ffuchsia-api-level' to allow
specify Fuchsia API level from the command line.
Differential Revision: https://reviews.llvm.org/D108592
An archive containing device code object files can be passed to
clang command line for linking. For each given offload target
it creates a device specific archives which is either passed to llvm-link
if the target is amdgpu, or to clang-nvlink-wrapper if the target is
nvptx. -L/-l flags are used to specify these fat archives on the command
line. E.g.
clang++ -fopenmp -fopenmp-targets=nvptx64 main.cpp -L. -lmylib
It currently doesn't support linking an archive directly, like:
clang++ -fopenmp -fopenmp-targets=nvptx64 main.cpp libmylib.a
Linking with x86 offload also does not work.
Reviewed By: ye-luo
Differential Revision: https://reviews.llvm.org/D105191
This patch adds two flags to be supported for the new runtime. The flags
are `-fopenmp-assume-threads-oversubscription` and
-fopenmp-assume-teams-oversubscription`. These add global values that
can be checked by the work sharing runtime functions to make better
judgements about how to distribute work between the threads.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D111348
An archive containing device code object files can be passed to
clang command line for linking. For each given offload target
it creates a device specific archives which is either passed to llvm-link
if the target is amdgpu, or to clang-nvlink-wrapper if the target is
nvptx. -L/-l flags are used to specify these fat archives on the command
line. E.g.
clang++ -fopenmp -fopenmp-targets=nvptx64 main.cpp -L. -lmylib
It currently doesn't support linking an archive directly, like:
clang++ -fopenmp -fopenmp-targets=nvptx64 main.cpp libmylib.a
Linking with x86 offload also does not work.
Reviewed By: ye-luo
Differential Revision: https://reviews.llvm.org/D105191
clang-cl maps /wdNNNN to -Wno-flags for a few warnings that map
cleanly from cl.exe concepts to clang concepts.
This patch adds support for the same numbers to
`#pragma warning(disable : NNNN)`. It also lets
`#pragma warning(push)` and `#pragma warning(pop)` have an effect,
since these are used together with `warning(disable)`.
The optional numeric argument to `warning(push)` is ignored,
as are the other non-`disable` `pragma warning()` arguments.
(Supporting `error` would be easy, but we also don't support
`/we`, and those should probably be added together.)
The motivating example is that a bunch of code (including in LLVM)
uses this idiom to locally disable warnings about calls to deprecated
functions in Windows-only code, and 4996 maps nicely to
-Wno-deprecated-declarations:
#pragma warning(push)
#pragma warning(disable: 4996)
f();
#pragma warning(pop)
Implementation-wise:
- Move `/wd` flag handling from Options.td to actual Driver-level code
- Extract the function mapping cl.exe IDs to warning groups to the
new file clang/lib/Basic/CLWarnings.cpp
- Create a diag::Group enum so that CLWarnings.cpp can refer to
existing groups by ID (and give DllexportExplicitInstantiationDecl
a named group), and add a function to map a diag::Group to the
spelling of it's associated commandline flag
- Call that new function from PragmaWarningHandler
Differential Revision: https://reviews.llvm.org/D110668
On AIX, we relied on LTO to merge the csects for profiling data/counter
sections.
AIX binder now get the namedcsect support to support the merging,
so now we can enable PGO without LTO with the new binder.
Reviewed By: Whitney
Differential Revision: https://reviews.llvm.org/D110671
This matches GCC.
Change the CC1 option to encode the unwind table level (1: needed by exceptions,
2: asynchronous) so that we can support two modes in the future.
This is to build the foundation of a new debug info feature to use only
the base name of template as its debug info name (eg: "t1" instead of
the full "t1<int>"). The intent being that a consumer can still retrieve
all that information from the DW_TAG_template_*_parameters.
So gno-simple-template-names is business as usual/previously ("t1<int>")
=simple is the simplified name ("t1")
=mangled is a special mode to communicate the full information, but
also indicate that the name should be able to be simplified. The data
is encoded as "_STNt1|<int>" which will be matched with an
llvm-dwarfdump --verify feature to deconstruct this name, rebuild the
original name, and then try to rebuild the simple name via the DWARF
tags - then compare the latter and the former to ensure that all the
data necessary to fully rebuild the name is present.
Summary:
Introduce a new frontend flag `-fswift-async-fp={auto|always|never}`
that controls how code generation sets the Swift extended async frame
info bit. There are three possibilities:
* `auto`: which determines how to set the bit based on deployment target, either
statically or dynamically via `swift_async_extendedFramePointerFlags`.
* `always`: default, always set the bit statically, regardless of deployment
target.
* `never`: never set the bit, regardless of deployment target.
Differential Revision: https://reviews.llvm.org/D109451
This patch introduces the flags `-fopenmp-target-debug` and
`-fopenmp-target-debug=` to set the value of a global in the device.
This will be used to enable or disable debugging features statically in
the device runtime library.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D109544
- Make flto an alias of flto=full.
- Make foffload-lto an alias of foffload-lto=full.
- Make flto_EQ_jobserver, flto_EQ_auto aliases of flto=full,
since they are being treated as full lto right now.
- Clean up the code for parseLTOMode and setLTOMode.
- Replace uses of OPT_flto with OPT_flto_EQ since they alias now.
Differential Revision: https://reviews.llvm.org/D108881
Change-Id: I5d867db83a680434fba5c8d85c9a83135d3b81ee
- Make flto an alias of flto=full.
- Make foffload-lto an alias of foffload-lto=full.
- Make flto_EQ_jobserver, flto_EQ_auto aliases of flto=full,
since they are being treated as full lto right now.
- Clean up the code for parseLTOMode and setLTOMode.
- Replace uses of OPT_flto with OPT_flto_EQ since they alias now.
Change-Id: Iea5338c20cb800b43529b20745e92600e2cfd2b1
Earlier BundleEntryID used to be <OffloadKind>-<Triple>-<GPUArch>.
This used to work because the clang-offload-bundler didn't need
GPUArch explicitly for any bundling/unbundling action. With
unbundleArchive it needs GPUArch to ensure compatibility between
device specific code objects. D93525 enforced triples to have
separators for all 4 components irrespective of number of
components, like "amdgcn-amd-amdhsa--". It was required to
to correctly parse a possible 4th environment component or a GPU.
But, this condition is breaking backward compatibility with
archive libraries compiled with compilers older than D93525.
This patch allows triples to have any number of components with
and without extra separator for empty environment field. Thus,
both the following bundle entry IDs are same:
openmp-amdgcn-amd-amdhsa--gfx906
openmp-amdgcn-amd-amdhsa-gfx906
Reviewed By: yaxunl, grokos
Differential Revision: https://reviews.llvm.org/D106809
Now prints the list of known archs. This requires plumbing a Driver
arg through a few functions.
Also add two more convenience insert() overlods to StringMap.
Differential Revision: https://reviews.llvm.org/D109105
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.
This patch implements Clang support for an original OpenMP extension
we have developed to support OpenACC: the `ompx_hold` map type
modifier. The next patch in this series, D106510, implements OpenMP
runtime support.
Consider the following example:
```
#pragma omp target data map(ompx_hold, tofrom: x) // holds onto mapping of x
{
foo(); // might have map(delete: x)
#pragma omp target map(present, alloc: x) // x is guaranteed to be present
printf("%d\n", x);
}
```
The `ompx_hold` map type modifier above specifies that the `target
data` directive holds onto the mapping for `x` throughout the
associated region regardless of any `target exit data` directives
executed during the call to `foo`. Thus, the presence assertion for
`x` at the enclosed `target` construct cannot fail. (As usual, the
standard OpenMP reference count for `x` must also reach zero before
the data is unmapped.)
Justification for inclusion in Clang and LLVM's OpenMP runtime:
* The `ompx_hold` modifier supports OpenACC functionality (structured
reference count) that cannot be achieved in standard OpenMP, as of
5.1.
* The runtime implementation for `ompx_hold` (next patch) will thus be
used by Flang's OpenACC support.
* The Clang implementation for `ompx_hold` (this patch) as well as the
runtime implementation are required for the Clang OpenACC support
being developed as part of the ECP Clacc project, which translates
OpenACC to OpenMP at the directive AST level. These patches are the
first step in upstreaming OpenACC functionality from Clacc.
* The Clang implementation for `ompx_hold` is also used by the tests
in the runtime implementation. That syntactic support makes the
tests more readable than low-level runtime calls can. Moreover,
upstream Flang and Clang do not yet support OpenACC syntax
sufficiently for writing the tests.
* More generally, the Clang implementation enables a clean separation
of concerns between OpenACC and OpenMP development in LLVM. That
is, LLVM's OpenMP developers can discuss, modify, and debug LLVM's
extended OpenMP implementation and test suite without directly
considering OpenACC's language and execution model, which can be
handled by LLVM's OpenACC developers.
* OpenMP users might find the `ompx_hold` modifier useful, as in the
above example.
See new documentation introduced by this patch in `openmp/docs` for
more detail on the functionality of this extension and its
relationship with OpenACC. For example, it explains how the runtime
must support two reference counts, as specified by OpenACC.
Clang recognizes `ompx_hold` unless `-fno-openmp-extensions`, a new
command-line option introduced by this patch, is specified.
Reviewed By: ABataev, jdoerfert, protze.joachim, grokos
Differential Revision: https://reviews.llvm.org/D106509