[ARM][AArch64] Add missing v8.x checks

Summary:
This patch adds checks that were missing in clang for Armv8.5/6/7-A. These include:
* ACLE macro defines for AArch32.
* Handling of crypto and SM4, SH

[ARM][AArch64] Add missing v8.x checks

Summary:
This patch adds checks that were missing in clang for Armv8.5/6/7-A. These include:
* ACLE macro defines for AArch32.
* Handling of crypto and SM4, SHA and AES feature flags on clang's driver.

Reviewers: dmgreen, SjoerdMeijer, tmatheson

Differential Revision: https://reviews.llvm.org/D116153

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[clang][ARM] Emit warnings when PACBTI-M is used with unsupported architectures

Branch protection in M-class is supported by
- Armv8.1-M.Main
- Armv8-M.Main
- Armv7-M

Attempting to enable this f

[clang][ARM] Emit warnings when PACBTI-M is used with unsupported architectures

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

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[ARM][AArch64] clang support for Armv9.3-A

This patch introduces support for targetting the Armv9.3-A architecture,
which should map to the existing Armv8.8-A extensions.

Differential Revision: htt

[ARM][AArch64] clang support for Armv9.3-A

This patch introduces support for targetting the Armv9.3-A architecture,
which should map to the existing Armv8.8-A extensions.

Differential Revision: https://reviews.llvm.org/D116159

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[ARM] Introduce an empty "armv8.8-a" architecture.

This is the first commit in a series that implements support for
"armv8.8-a" architecture. This should contain all the necessary
boilerplate to mak

[ARM] Introduce an empty "armv8.8-a" architecture.

This is the first commit in a series that implements support for
"armv8.8-a" architecture. This should contain all the necessary
boilerplate to make the 8.8-A architecture exist from LLVM and Clang's
point of view: it adds the new arch as a subtarget feature, a definition
in TargetParser, a name on the command line, an appropriate set of
predefined macros, and adds appropriate tests. The new architecture name
is supported in both AArch32 and AArch64.

However, in this commit, no actual _functionality_ is added as part of
the new architecture. If you specify -march=armv8.8a, the compiler
will accept it and set the right predefines, but generate no code any
differently.

Differential Revision: https://reviews.llvm.org/D115694

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[ARM][clang] Option b-key must not affect __ARM_FEATURE_PAC_DEFAULT

When using -mbranch-protection=pac-ret+b-key, macro __ARM_FEATURE_PAC_DEFAULT
should still have the value corresponding to a-key,

[ARM][clang] Option b-key must not affect __ARM_FEATURE_PAC_DEFAULT

When using -mbranch-protection=pac-ret+b-key, macro __ARM_FEATURE_PAC_DEFAULT
should still have the value corresponding to a-key, because b-key is only valid
for AArch64.

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:

- Victor Campos

Reviewed By: danielkiss

Differential Revision: https://reviews.llvm.org/D115140

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[ARM][clang] Define feature test macro for the PACBTI-M extension

If the extension string "+pacbti" was given in -march=... or -mcpu=... options the compiler shall define the following preprocessor

[ARM][clang] Define feature test macro for the PACBTI-M extension

If the extension string "+pacbti" was given in -march=... or -mcpu=... options the compiler shall define the following preprocessor macros:

__ARM_FEATURE_PAUTH with value 1.
__ARM_FEATURE_BTI with value 1.

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
- Ties Stuij

Reviewed By: miyuki

Differential Revision: https://reviews.llvm.org/D112431

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[clang][ARM] emit PACBTI-M feature defines

emit __ARM_FEATURE_BTI_DEFAULT and __ARM_FEATURE_PAC_DEFAULT defines when those
features have been enabled

This patch is part of a series that adds suppor

[clang][ARM] emit PACBTI-M feature defines

emit __ARM_FEATURE_BTI_DEFAULT and __ARM_FEATURE_PAC_DEFAULT defines when those
features have been enabled

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:

- Victor Campos
- Ties Stuij

Reviewed By: ostannard

Differential Revision: https://reviews.llvm.org/D112422

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[clang][ARM] PACBTI-M frontend support

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 mech

[clang][ARM] PACBTI-M frontend support

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

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[ARM] Fix inline assembly referencing floating point registers on soft-float targets

Fixes PR: https://bugs.llvm.org/show_bug.cgi?id=52230

Reviewed By: nickdesaulniers

Differential Revision: https

[ARM] Fix inline assembly referencing floating point registers on soft-float targets

Fixes PR: https://bugs.llvm.org/show_bug.cgi?id=52230

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D112135

OS Laboratory, Huawei Russian Research Institute, Saint-Petersburg

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[Clang][ARM][AArch64] Add support for Armv9-A, Armv9.1-A and Armv9.2-A

armv9-a, armv9.1-a and armv9.2-a can be targeted using the -march option
both in ARM and AArch64.

- Armv9-A maps to Armv8.5-A

[Clang][ARM][AArch64] Add support for Armv9-A, Armv9.1-A and Armv9.2-A

armv9-a, armv9.1-a and armv9.2-a can be targeted using the -march option
both in ARM and AArch64.

- Armv9-A maps to Armv8.5-A.
- Armv9.1-A maps to Armv8.6-A.
- Armv9.2-A maps to Armv8.7-A.
- The SVE2 extension is enabled by default on these architectures.
- The cryptographic extensions are disabled by default on these
architectures.

The Armv9-A architecture is described in the Arm® Architecture Reference
Manual Supplement Armv9, for Armv9-A architecture profile
(https://developer.arm.com/documentation/ddi0608/latest).

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D109517

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[Clang] Introduce Swift async calling convention.

This change is intended as initial setup. The plan is to add
more semantic checks later. I plan to update the documentation
as more semantic checks

[Clang] Introduce Swift async calling convention.

This change is intended as initial setup. The plan is to add
more semantic checks later. I plan to update the documentation
as more semantic checks are added (instead of documenting the
details up front). Most of the code closely mirrors that for
the Swift calling convention. Three places are marked as
[FIXME: swiftasynccc]; those will be addressed once the
corresponding convention is introduced in LLVM.

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D95561

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[ARM][AArch64] Correct __ARM_FEATURE_CRYPTO macro and crypto feature

This patch contains a couple of minor corrections to my previous
crypto patch:

Since both AArch32 and AArch64 are now correctly

[ARM][AArch64] Correct __ARM_FEATURE_CRYPTO macro and crypto feature

This patch contains a couple of minor corrections to my previous
crypto patch:

Since both AArch32 and AArch64 are now correctly setting the aes and
sha2 features individually, it is not necessary to continue to check
the crypto feature when defining feature macros.

In the AArch32 driver, the feature vector is only modified when the
crypto feature is actually in the vector. If crypto is not present,
there is no need to split it and explicitly define crypto/sha2/aes.

Reviewed By: lenary

Differential Revision: https://reviews.llvm.org/D102406

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[ARM][AArch64] Require appropriate features for crypto algorithms

This patch changes the AArch32 crypto instructions (sha2 and aes) to
require the specific sha2 or aes features. These features have

[ARM][AArch64] Require appropriate features for crypto algorithms

This patch changes the AArch32 crypto instructions (sha2 and aes) to
require the specific sha2 or aes features. These features have
already been implemented and can be controlled through the command
line, but do not have the expected result (i.e. `+noaes` will not
disable aes instructions). The crypto feature retains its existing
meaning of both sha2 and aes.

Several small changes are included due to the knock-on effect this has:

- The AArch32 driver has been modified to ensure sha2/aes is correctly
set based on arch/cpu/fpu selection and feature ordering.
- Crypto extensions are permitted for AArch32 v8-R profile, but not
enabled by default.
- ACLE feature macros have been updated with the fine grained crypto
algorithms. These are also used by AArch64.
- Various tests updated due to the change in feature lists and macros.

Reviewed By: lenary

Differential Revision: https://reviews.llvm.org/D99079

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[clang/Basic] Make TargetInfo.h not use DataLayout again

Reverts parts of https://reviews.llvm.org/D17183, but keeps the
resetDataLayout() API and adds an assert that checks that datalayout string a

[clang/Basic] Make TargetInfo.h not use DataLayout again

Reverts parts of https://reviews.llvm.org/D17183, but keeps the
resetDataLayout() API and adds an assert that checks that datalayout string and
user label prefix are in sync.

Approach 1 in https://reviews.llvm.org/D17183#2653279
Reduces number of TUs build for 'clang-format' from 689 to 575.

I also implemented approach 2 in D100764. If someone feels motivated
to make us use DataLayout more, it's easy to revert this change here
and go with D100764 instead. I don't plan on doing more work in this
area though, so I prefer going with the smaller, more self-consistent change.

Differential Revision: https://reviews.llvm.org/D100776

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[Clang][ARM] Define __VFP_FP__ macro unconditionally

Clang only defines __VFP_FP__ when the FPU is enabled. However, gcc
defines it unconditionally.

This patch aligns Clang with gcc.

Reviewed By:

[Clang][ARM] Define __VFP_FP__ macro unconditionally

Clang only defines __VFP_FP__ when the FPU is enabled. However, gcc
defines it unconditionally.

This patch aligns Clang with gcc.

Reviewed By: peter.smith, rengolin

Differential Revision: https://reviews.llvm.org/D100372

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[ARM] Adding v8.7-A command-line support for the ARM target

This extends the command-line support for the 'armv8.7-a' architecture
name to the ARM target.

Based on a patch written by Momchil Veliko

[ARM] Adding v8.7-A command-line support for the ARM target

This extends the command-line support for the 'armv8.7-a' architecture
name to the ARM target.

Based on a patch written by Momchil Velikov.

Reviewed By: ostannard

Differential Revision: https://reviews.llvm.org/D93231

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[clang][BFloat] add NEON emitter for bfloat

Summary:
This patch adds the bfloat16_t struct typedefs (e.g. bfloat16x8x2_t) to
arm_neon.h

This patch is part of a series implementing the Bfloat16 exte

[clang][BFloat] add NEON emitter for bfloat

Summary:
This patch adds the bfloat16_t struct typedefs (e.g. bfloat16x8x2_t) to
arm_neon.h

This patch is part of a series implementing the Bfloat16 extension of the
Armv8.6-a architecture, as detailed here:

https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a

The bfloat type, and its properties are specified in the Arm Architecture
Reference Manual:

https://developer.arm.com/docs/ddi0487/latest/arm-architecture-reference-manual-armv8-for-armv8-a-architecture-profile

The following people contributed to this patch:
- Luke Cheeseman
- Simon Tatham
- Ties Stuij

Reviewers: t.p.northover, fpetrogalli, sdesmalen, az, LukeGeeson

Reviewed By: fpetrogalli

Subscribers: SjoerdMeijer, LukeGeeson, pbarrio, mgorny, kristof.beyls, ilya-biryukov, MaskRay, jkorous, arphaman, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79708

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[ARM] Add __bf16 as new Bfloat16 C Type

Summary:
This patch upstreams support for a new storage only bfloat16 C type.
This type is used to implement primitive support for bfloat16 data, in
line with

[ARM] Add __bf16 as new Bfloat16 C Type

Summary:
This patch upstreams support for a new storage only bfloat16 C type.
This type is used to implement primitive support for bfloat16 data, in
line with the Bfloat16 extension of the Armv8.6-a architecture, as
detailed here:

https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a

The bfloat type, and its properties are specified in the Arm Architecture
Reference Manual:

https://developer.arm.com/docs/ddi0487/latest/arm-architecture-reference-manual-armv8-for-armv8-a-architecture-profile

In detail this patch:
- introduces an opaque, storage-only C-type __bf16, which introduces a new bfloat IR type.

This is part of a patch series, starting with command-line and Bfloat16
assembly support. The subsequent patches will upstream intrinsics
support for BFloat16, followed by Matrix Multiplication and the
remaining Virtualization features of the armv8.6-a architecture.

The following people contributed to this patch:
- Luke Cheeseman
- Momchil Velikov
- Alexandros Lamprineas
- Luke Geeson
- Simon Tatham
- Ties Stuij

Reviewers: SjoerdMeijer, rjmccall, rsmith, liutianle, RKSimon, craig.topper, jfb, LukeGeeson, fpetrogalli

Reviewed By: SjoerdMeijer

Subscribers: labrinea, majnemer, asmith, dexonsmith, kristof.beyls, arphaman, danielkiss, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76077

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[Clang][A32/T32][Linux] -O1 implies -fomit-frame-pointer

Summary:
An upgrade of LLVM for CrOS [0] containing [1] triggered a bunch of
errors related to writing to reserved registers for a Linux kern

[Clang][A32/T32][Linux] -O1 implies -fomit-frame-pointer

Summary:
An upgrade of LLVM for CrOS [0] containing [1] triggered a bunch of
errors related to writing to reserved registers for a Linux kernel's
arm64 compat vdso (which is a aarch32 image).

After a discussion on LKML [2], it was determined that
-f{no-}omit-frame-pointer was not being specified. Comparing GCC and
Clang [3], it becomes apparent that GCC defaults to omitting the frame
pointer implicitly when optimizations are enabled, and Clang does not.
ie. setting -O1 (or above) implies -fomit-frame-pointer. Clang was
defaulting to -fno-omit-frame-pointer implicitly unless -fomit-frame-pointer
was set explicitly.

Why this becomes a problem is that the Linux kernel's arm64 compat vdso
contains code that uses r7. r7 is used sometimes for the frame pointer
(for example, when targeting thumb (-mthumb)). See useR7AsFramePointer()
in llvm/llvm-project/llvm/lib/Target/ARM/ARMSubtarget.h. This is mostly
for legacy/compatibility reasons, and the 2019 Q4 revision of the ARM
AAPCS looks to standardize r11 as the frame pointer for aarch32, though
this is not yet implemented in LLVM.

Users that are reliant on the implicit value if unspecified when
optimizations are enabled should explicitly choose -fomit-frame-pointer
(new behavior) or -fno-omit-frame-pointer (old behavior).

[0] https://bugs.chromium.org/p/chromium/issues/detail?id=1084372
[1] https://reviews.llvm.org/D76848
[2] https://lore.kernel.org/lkml/[email protected]/
[3] https://godbolt.org/z/0oY39t

Reviewers: kristof.beyls, psmith, danalbert, srhines, MaskRay, ostannard, efriedma

Reviewed By: psmith, danalbert, srhines, MaskRay, efriedma

Subscribers: efriedma, olista01, MaskRay, vhscampos, cfe-commits, llvm-commits, manojgupta, llozano, glider, hctim, eugenis, pcc, peter.smith, srhines

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D80828

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[AArch32] Armv8.6-a Matrix Mult Assembly + Intrinsics

This patch upstreams support for the Armv8.6-a Matrix Multiplication
Extension. A summary of the features can be found here:

https://community.

[AArch32] Armv8.6-a Matrix Mult Assembly + Intrinsics

This patch upstreams support for the Armv8.6-a Matrix Multiplication
Extension. A summary of the features can be found here:

https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a

This patch includes:

- Assembly support for AArch32
- Intrinsics Support for AArch32 Neon Intrinsics for Matrix
Multiplication

Note: these extensions are optional in the 8.6a architecture and so have
to be enabled by default

No additional IR types or C Types are needed for this extension.

This is part of a patch series, starting with BFloat16 support and
the other components in the armv8.6a extension (in previous patches
linked in phabricator)

Based on work by:
- Luke Geeson
- Oliver Stannard
- Luke Cheeseman

Reviewers: t.p.northover, miyuki

Reviewed By: miyuki

Subscribers: miyuki, ostannard, kristof.beyls, hiraditya, danielkiss,
cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77872

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[PATCH] [ARM] ARMv8.6-a command-line + BFloat16 Asm Support

Summary:
This patch introduces command-line support for the Armv8.6-a architecture and assembly support for BFloat16. Details can be found

[PATCH] [ARM] ARMv8.6-a command-line + BFloat16 Asm Support

Summary:
This patch introduces command-line support for the Armv8.6-a architecture and assembly support for BFloat16. Details can be found
https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a

in addition to the GCC patch for the 8..6-a CLI:
https://gcc.gnu.org/legacy-ml/gcc-patches/2019-11/msg02647.html

In detail this patch

- march options for armv8.6-a
- BFloat16 assembly

This is part of a patch series, starting with command-line and Bfloat16
assembly support. The subsequent patches will upstream intrinsics
support for BFloat16, followed by Matrix Multiplication and the
remaining Virtualization features of the armv8.6-a architecture.

Based on work by:
- labrinea
- MarkMurrayARM
- Luke Cheeseman
- Javed Asbar
- Mikhail Maltsev
- Luke Geeson

Reviewers: SjoerdMeijer, craig.topper, rjmccall, jfb, LukeGeeson

Reviewed By: SjoerdMeijer

Subscribers: stuij, kristof.beyls, hiraditya, dexonsmith, danielkiss, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D76062

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[ARM,CDE] Implement CDE feature test macros

Summary:
This patch implements feature test macros for the CDE extension
according to the upcoming ACLE specification.

The following 2 macros are being a

[ARM,CDE] Implement CDE feature test macros

Summary:
This patch implements feature test macros for the CDE extension
according to the upcoming ACLE specification.

The following 2 macros are being added:
- __ARM_FEATURE_CDE - defined as '1' when any coprocessor is
configured as a CDE coprocessor
- __ARM_FEATURE_CDE_COPROC - defined as an 8-bit mask, each bit of the
mask corresponds to a coprocessor and is set when the corresponding
coprocessor is configured as CDE (and cleared otherwise).

The patch also exposes the value of __ARM_FEATURE_CDE_COPROC in the
target-independent method TargetInfo::getARMCDECorpocMask, the method
will be used in follow-up patches implementing semantic checks of CDE
intrinsics (we want to diagnose the cases when CDE intrinsics are used
with coprocessors that are not configured as CDE).

Reviewers: simon_tatham, dmgreen, ostannard, MarkMurrayARM

Reviewed By: simon_tatham

Subscribers: kristof.beyls, danielkiss, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75843

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[ARM][TargetParser] Improve handling of dependencies between target features

The patch at https://reviews.llvm.org/D64048 added "negative"
dependency handling in `ARM::appendArchExtFeatures`: featur

[ARM][TargetParser] Improve handling of dependencies between target features

The patch at https://reviews.llvm.org/D64048 added "negative"
dependency handling in `ARM::appendArchExtFeatures`: feature "noX"
removes all features, which imply "X".

This patch adds the "positive" handling: feature "X" adds all the
feature strings implied by "X".

(This patch also comes from the suggestion here
https://reviews.llvm.org/D72633#inline-658582)

Differential Revision: https://reviews.llvm.org/D72762

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[ARM] Make ARM::ArchExtKind use 64-bit underlying type, NFCI

Summary:
This patch changes the underlying type of the ARM::ArchExtKind
enumeration to uint64_t and adjusts the related code.

The goal o

[ARM] Make ARM::ArchExtKind use 64-bit underlying type, NFCI

Summary:
This patch changes the underlying type of the ARM::ArchExtKind
enumeration to uint64_t and adjusts the related code.

The goal of the patch is to prepare the code base for a new
architecture extension.

Reviewers: simon_tatham, eli.friedman, ostannard, dmgreen

Reviewed By: dmgreen

Subscribers: merge_guards_bot, kristof.beyls, hiraditya, cfe-commits, llvm-commits, pbarrio

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D73906

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Make llvm::StringRef to std::string conversions explicit.

This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.

This is mostly m

Make llvm::StringRef to std::string conversions explicit.

This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.

This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.

This doesn't actually modify StringRef yet, I'll do that in a follow-up.

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