Commit Graph

96 Commits

Author SHA1 Message Date
Alexey Bader 8d27be8dba [OpenCL] Add global_device and global_host address spaces
This patch introduces 2 new address spaces in OpenCL: global_device and global_host
which are a subset of a global address space, so the address space scheme will be
looking like:

```
generic->global->host
                          ->device
             ->private
             ->local
constant
```

Justification: USM allocations may be associated with both host and device memory. We
want to give users a way to tell the compiler the allocation type of a USM pointer for
optimization purposes. (Link to the Unified Shared Memory extension:
https://github.com/intel/llvm/blob/sycl/sycl/doc/extensions/USM/cl_intel_unified_shared_memory.asciidoc)

Before this patch USM pointer could be only in opencl_global
address space, hence a device backend can't tell if a particular pointer
points to host or device memory. On FPGAs at least we can generate more
efficient hardware code if the user tells us where the pointer can point -
being able to distinguish between these types of pointers at compile time
allows us to instantiate simpler load-store units to perform memory
transactions.

Patch by Dmitry Sidorov.

Reviewed By: Anastasia

Differential Revision: https://reviews.llvm.org/D82174
2020-07-29 17:24:53 +03:00
Akira Hatanaka 73bc23ff86 Fix the data layout mangling specification for 'i686-pc-macho'
Use 'o' for the mangling specification instead of 'e'. This fixes an
error in the backend caused by a mismatch between the data layouts
generated by the backend and the frontend.

rdar://problem/64168540
2020-07-21 12:58:17 -07:00
Kevin P. Neal d4ce862f2a Reland "[FPEnv][Clang][Driver] Disable constrained floating point on targets lacking support."
We currently have strict floating point/constrained floating point enabled
for all targets. Constrained SDAG nodes get converted to the regular ones
before reaching the target layer. In theory this should be fine.

However, the changes are exposed to users through multiple clang options
already in use in the field, and the changes are _completely_ _untested_
on almost all of our targets. Bugs have already been found, like
"https://bugs.llvm.org/show_bug.cgi?id=45274".

This patch disables constrained floating point options in clang everywhere
except X86 and SystemZ. A warning will be printed when this happens.

Use the new -fexperimental-strict-floating-point flag to force allowing
strict floating point on hosts that aren't already marked as supporting
it (X86 and SystemZ).

Differential Revision: https://reviews.llvm.org/D80952
2020-07-10 08:49:45 -04:00
Craig Topper 3cbfe988bc [X86] Merge X86TargetInfo::setFeatureEnabled and X86TargetInfo::setFeatureEnabledImpl. NFC
setFeatureEnabled is a virtual function. setFeatureEnabledImpl
was its implementation. This split was to avoid virtual calls
when we need to call setFeatureEnabled in initFeatureMap.

With C++11 we can use 'final' on setFeatureEnabled to enable
the compiler to perform de-virtualization for the initFeatureMap
calls.
2020-07-06 23:54:56 -07:00
Craig Topper 16f3d698f2 [X86] Move the feature dependency handling in X86TargetInfo::setFeatureEnabledImpl to a table based lookup in X86TargetParser.cpp
Previously we had to specify the forward and backwards feature dependencies separately which was error prone. And as dependencies have gotten more complex it was hard to be sure the transitive dependencies were handled correctly. The way it was written was also not super readable.

This patch replaces everything with a table that lists what features a feature is dependent on directly. Then we can recursively walk through the table to find the transitive dependencies. This is largely based on how we handle subtarget features in the MC layer from the tablegen descriptions.

Differential Revision: https://reviews.llvm.org/D83273
2020-07-06 23:14:02 -07:00
Xiang1 Zhang 939d8309db [X86-64] Support Intel AMX Intrinsic
INTEL ADVANCED MATRIX EXTENSIONS (AMX).
AMX is a new programming paradigm, it has a set of 2-dimensional registers
(TILES) representing sub-arrays from a larger 2-dimensional memory image and
operate on TILES.

These intrinsics use direct TMM register number as its params.

Spec can be found in Chapter 3 here https://software.intel.com/content/www/us/en/develop/download/intel-architecture-instruction-set-extensions-programming-reference.html

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D83111
2020-07-07 10:13:40 +08:00
Kevin P. Neal 916e2ca997 Revert "[FPEnv][Clang][Driver] Disable constrained floating point on targets lacking support."
My mistake, I had a blocking reviewer.

This reverts commit 39d2ae0afb.
This reverts commit bfdafa32a0.
This reverts commit 2b35511350.

Differential Revision: https://reviews.llvm.org/D80952
2020-07-06 14:57:45 -04:00
Kevin P. Neal 39d2ae0afb [FPEnv][Clang][Driver] Disable constrained floating point on targets lacking support.
We currently have strict floating point/constrained floating point enabled
for all targets. Constrained SDAG nodes get converted to the regular ones
before reaching the target layer. In theory this should be fine.

However, the changes are exposed to users through multiple clang options
already in use in the field, and the changes are _completely_ _untested_
on almost all of our targets. Bugs have already been found, like
"https://bugs.llvm.org/show_bug.cgi?id=45274".

This patch disables constrained floating point options in clang everywhere
except X86 and SystemZ. A warning will be printed when this happens.

Differential Revision: https://reviews.llvm.org/D80952
2020-07-06 13:32:49 -04:00
Craig Topper d5c28c4094 [X86] Move CPUKind enum from clang to llvm/lib/Support. NFCI
Similar to what some other targets have done. This information
could be reused by other frontends so doesn't make sense to live
in clang.

-Rename CK_Generic to CK_None to better reflect its illegalness.
-Move function for translating from string to enum into llvm.
-Call checkCPUKind directly from the string to enum translation
and update CPU kind to CK_None accordinly. Caller will use CK_None
as sentinel for bad CPU.

I'm planning to move all the CPU to feature mapping out next. As
part of that I want to devise a better way to express CPUs inheriting
features from an earlier CPU. Allowing this to be expressed in a
less rigid way than just falling through a switch. Or using gotos
as we've had to do lately.

Differential Revision: https://reviews.llvm.org/D81439
2020-06-09 12:52:41 -07:00
Erich Keane 911add149a Disable _ExtInt by default
Since the _ExtInt type got into the repo, we've discovered that the ABI
implications weren't completely understood. The other architectures are
going to be audited (see D79118), however downstream targets aren't
going to benefit from this audit.

This patch disables the _ExtInt type by default and makes the
target-info an opt-in.  As it is audited, I'll re-enable these for all
of our default targets.
2020-04-29 13:48:12 -07:00
WangTianQing a3dc949000 [X86] Add TSXLDTRK instructions.
Summary: For more details about these instructions, please refer to the latest ISE document: https://software.intel.com/en-us/download/intel-architecture-instruction-set-extensions-programming-reference

Reviewers: craig.topper, RKSimon, LuoYuanke

Reviewed By: craig.topper

Subscribers: mgorny, hiraditya, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77205
2020-04-09 13:17:29 +08:00
WangTianQing d08fadd662 [X86] Add SERIALIZE instruction.
Summary: For more details about this instruction, please refer to the latest ISE document: https://software.intel.com/en-us/download/intel-architecture-instruction-set-extensions-programming-reference

Reviewers: craig.topper, RKSimon, LuoYuanke

Reviewed By: craig.topper

Subscribers: mgorny, hiraditya, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77193
2020-04-02 16:19:23 +08:00
zoecarver b915aec6b5 Add method to TargetInfo to get CPU cache line size
Summary:
This patch adds a virtual method `getCPUCacheLineSize()` to `TargetInfo`. Currently, I've only implemented the method in `X86TargetInfo`. It's extremely important that each CPU's cache line size correct (e.g., we can't just define it as `64` across the board) so, it has been a little slow getting to this point.

I'll work on the ARM CPUs next, but that will probably come later in a different patch.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74918
2020-03-25 09:50:38 -07:00
serge_sans_paille e67cbac812 Support -fstack-clash-protection for x86
Implement protection against the stack clash attack [0] through inline stack
probing.

Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].

This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.

Only implemented for x86.

[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html

This a recommit of 39f50da2a3 with proper LiveIn
declaration, better option handling and more portable testing.

Differential Revision: https://reviews.llvm.org/D68720
2020-02-09 10:42:45 +01:00
serge-sans-paille 4546211600 Revert "Support -fstack-clash-protection for x86"
This reverts commit 0fd51a4554.

Failures:

http://lab.llvm.org:8011/builders/llvm-clang-win-x-armv7l/builds/4354
2020-02-09 10:06:31 +01:00
serge_sans_paille 0fd51a4554 Support -fstack-clash-protection for x86
Implement protection against the stack clash attack [0] through inline stack
probing.

Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].

This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.

Only implemented for x86.

[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html

This a recommit of 39f50da2a3 with proper LiveIn
declaration, better option handling and more portable testing.

Differential Revision: https://reviews.llvm.org/D68720
2020-02-09 09:35:42 +01:00
serge-sans-paille 658495e6ec Revert "Support -fstack-clash-protection for x86"
This reverts commit e229017732.

Failures:

http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-debian/builds/2604
http://lab.llvm.org:8011/builders/llvm-clang-win-x-aarch64/builds/4308
2020-02-08 14:26:22 +01:00
serge_sans_paille e229017732 Support -fstack-clash-protection for x86
Implement protection against the stack clash attack [0] through inline stack
probing.

Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].

This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.

Only implemented for x86.

[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html

This a recommit of 39f50da2a3 with better option
handling and more portable testing

Differential Revision: https://reviews.llvm.org/D68720
2020-02-08 13:31:52 +01:00
Nico Weber b03c3d8c62 Revert "Support -fstack-clash-protection for x86"
This reverts commit 4a1a0690ad.
Breaks tests on mac and win, see https://reviews.llvm.org/D68720
2020-02-07 14:49:38 -05:00
serge_sans_paille 4a1a0690ad Support -fstack-clash-protection for x86
Implement protection against the stack clash attack [0] through inline stack
probing.

Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].

This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.

Only implemented for x86.

[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html

This a recommit of 39f50da2a3 with correct option
flags set.

Differential Revision: https://reviews.llvm.org/D68720
2020-02-07 19:54:39 +01:00
serge-sans-paille f6d98429fc Revert "Support -fstack-clash-protection for x86"
This reverts commit 39f50da2a3.

The -fstack-clash-protection is being passed to the linker too, which
is not intended.

Reverting and fixing that in a later commit.
2020-02-07 11:36:53 +01:00
serge_sans_paille 39f50da2a3 Support -fstack-clash-protection for x86
Implement protection against the stack clash attack [0] through inline stack
probing.

Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].

This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.

Only implemented for x86.

[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html

Differential Revision: https://reviews.llvm.org/D68720
2020-02-07 10:56:15 +01:00
Craig Topper d35bcbbb5d [Sema][X86] Consider target attribute into the checks in validateOutputSize and validateInputSize.
The validateOutputSize and validateInputSize need to check whether
AVX or AVX512 are enabled. But this can be affected by the
target attribute so we need to factor that in.

This patch moves some of the code from CodeGen to create an
appropriate feature map that we can pass to the function.

Differential Revision: https://reviews.llvm.org/D68627
2019-12-23 11:23:30 -08:00
Amy Huang a85f5efd95 Add support for the MS qualifiers __ptr32, __ptr64, __sptr, __uptr.
Summary:
This adds parsing of the qualifiers __ptr32, __ptr64, __sptr, and __uptr and
lowers them to the corresponding address space pointer for 32-bit and 64-bit pointers.
(32/64-bit pointers added in https://reviews.llvm.org/D69639)

A large part of this patch is making these pointers ignore the address space
when doing things like overloading and casting.

https://bugs.llvm.org/show_bug.cgi?id=42359

Reviewers: rnk, rsmith

Subscribers: jholewinski, jvesely, nhaehnle, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71039
2019-12-18 10:41:12 -08:00
Reid Kleckner eff08f4097 Revert "[Sema][X86] Consider target attribute into the checks in validateOutputSize and validateInputSize."
This reverts commit e1578fd2b7.

It introduces a dependency on Attr.h which I am removing from
ASTContext.h.
2019-12-06 15:42:14 -08:00
Craig Topper e1578fd2b7 [Sema][X86] Consider target attribute into the checks in validateOutputSize and validateInputSize.
The validateOutputSize and validateInputSize need to check whether
AVX or AVX512 are enabled. But this can be affected by the
target attribute so we need to factor that in.

This patch copies some of the code from CodeGen to create an
appropriate feature map that we can pass to the function. Probably
need some refactoring here to share more code with Codegen. Is
there a good place to do that? Also need to support the cpu_specific
attribute as well.

Differential Revision: https://reviews.llvm.org/D68627
2019-12-06 15:30:59 -08:00
Amy Huang 7b1d793713 Reland "Change the X86 datalayout to add three address spaces
for 32 bit signed, 32 bit unsigned, and 64 bit pointers."
This reverts 57076d3199.

Original review at https://reviews.llvm.org/D64931.
Review for added fix at https://reviews.llvm.org/D66843.

llvm-svn: 371568
2019-09-10 23:15:38 +00:00
Craig Topper 5a43fdd313 [X86] Remove what little support we had for MPX
-Deprecate -mmpx and -mno-mpx command line options
-Remove CPUID detection of mpx for -march=native
-Remove MPX from all CPUs
-Remove MPX preprocessor define

I've left the "mpx" string in the backend so we don't fail on old IR, but its not connected to anything.

gcc has also deprecated these command line options. https://www.phoronix.com/scan.php?page=news_item&px=GCC-Patch-To-Drop-MPX

Differential Revision: https://reviews.llvm.org/D66669

llvm-svn: 370393
2019-08-29 18:09:02 +00:00
Vlad Tsyrklevich 57076d3199 Revert "Change the X86 datalayout to add three address spaces for 32 bit signed,"
This reverts commit r370083 because it caused check-lld failures on
sanitizer-x86_64-linux-fast.

llvm-svn: 370142
2019-08-28 01:08:54 +00:00
Amy Huang 1299945b81 Change the X86 datalayout to add three address spaces for 32 bit signed,
32 bit unsigned, and 64 bit pointers.

llvm-svn: 370083
2019-08-27 17:46:53 +00:00
Erich Keane 393094859e Remove CallingConvMethodType
This seems to be an old vestage of a previous implementation of getting
the default calling convention, and everything is now using
CXXABI/ASTContext's getDefaultCallingConvention.  Remove it, since it
isn't doing anything.

llvm-svn: 367039
2019-07-25 17:14:45 +00:00
Fangrui Song c46d78d1b7 [X86][PowerPC] Support -mlong-double-128
This patch makes the driver option -mlong-double-128 available for X86
and PowerPC. The CC1 option -mlong-double-128 is available on all targets
for users to test on unsupported targets.

On PowerPC, -mlong-double-128 uses the IBM extended double format
because we don't support -mabi=ieeelongdouble yet (D64283).

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D64277

llvm-svn: 365866
2019-07-12 02:32:15 +00:00
Reid Kleckner 8777df5270 De-templatize non-dependent VS macro logic, NFC
These macro definitions don't depend on the template parameter, so they
don't need to be part of the template. Move them to a .cpp file.

llvm-svn: 365556
2019-07-09 20:57:28 +00:00
Fangrui Song 04615341e4 [ItaniumMangle] Refactor long double/__float128 mangling and fix the mangled code
In gcc PowerPC, long double has 3 mangling schemes:

-mlong-double-64: `e`
-mlong-double-128 -mabi=ibmlongdouble: `g`
-mlong-double-128 -mabi=ieeelongdouble: `u9__ieee128` (gcc <= 8.1: `U10__float128`)

The current useFloat128ManglingForLongDouble() bisection is not suitable
when we support -mlong-double-128 in clang (D64277). Replace
useFloat128ManglingForLongDouble() with getLongDoubleMangling() and
getFloat128Mangling() to allow 3 mangling schemes.

I also deleted the `getTriple().isOSBinFormatELF()` check (the Darwin
support has gone: https://reviews.llvm.org/D50988).

For x86, change the mangled code of __float128 from `U10__float128` to `g`. `U10__float128` was wrongly copied from PowerPC.
The test will be added to `test/CodeGen/x86-long-double.cpp` in D64277.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D64276

llvm-svn: 365480
2019-07-09 13:32:26 +00:00
Pengfei Wang 3a29f7c99c [X86] Add ENQCMD instructions
For more details about these instructions, please refer to the latest
ISE document:
https://software.intel.com/en-us/download/intel-architecture-instruction-set-extensions-programming-reference.

Patch by Tianqing Wang (tianqing)

Differential Revision: https://reviews.llvm.org/D62282

llvm-svn: 362685
2019-06-06 08:28:42 +00:00
Pengfei Wang cc3629d545 [X86] Add VP2INTERSECT instructions
Support intel AVX512 VP2INTERSECT instructions in clang

Patch by Xiang Zhang (xiangzhangllvm)

Differential Revision: https://reviews.llvm.org/D62367

llvm-svn: 362196
2019-05-31 06:09:35 +00:00
Luo, Yuanke 844f662932 Enable intrinsics of AVX512_BF16, which are supported for BFLOAT16 in Cooper Lake
Summary:
1. Enable infrastructure of AVX512_BF16, which is supported for BFLOAT16 in Cooper Lake;
2. Enable intrinsics for VCVTNE2PS2BF16, VCVTNEPS2BF16 and DPBF16PS instructions, which are Vector Neural Network Instructions supporting BFLOAT16 inputs and conversion instructions from IEEE single precision.
For more details about BF16 intrinsic, please refer to the latest ISE document: https://software.intel.com/en-us/download/intel-architecture-instruction-set-extensions-programming-reference

Patch by LiuTianle

Reviewers: craig.topper, smaslov, LuoYuanke, wxiao3, annita.zhang, spatel, RKSimon

Reviewed By: craig.topper

Subscribers: mgorny, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D60552

llvm-svn: 360018
2019-05-06 08:25:11 +00:00
Craig Topper 7339e61b89 [X86] Correct the value of MaxAtomicInlineWidth for pre-586 cpus
Use the new cx8 feature flag that was added to the backend to represent support for cmpxchg8b. Use this flag to set the MaxAtomicInlineWidth.

This also assumes all the cmpxchg instructions are enabled for CK_Generic which is what cc1 defaults to when nothing is specified.

Differential Revision: https://reviews.llvm.org/D59566

llvm-svn: 356709
2019-03-21 20:36:08 +00:00
Craig Topper 140f766f14 [X86] Remove getCPUKindCanonicalName which is unused.
Differential Revision: https://reviews.llvm.org/D59578

llvm-svn: 356580
2019-03-20 17:26:51 +00:00
Nirav Dave 91ecb69acd [X86] Prevent clang clobber checking for asm flag constraints.
Update getConstraintRegister as X86 Asm flag output constraints are no
longer fully alphanumeric,

llvm-svn: 354211
2019-02-17 03:53:23 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Reid Kleckner 4dc0b1ac60 Fix clang -Wimplicit-fallthrough warnings across llvm, NFC
This patch should not introduce any behavior changes. It consists of
mostly one of two changes:
1. Replacing fall through comments with the LLVM_FALLTHROUGH macro
2. Inserting 'break' before falling through into a case block consisting
   of only 'break'.

We were already using this warning with GCC, but its warning behaves
slightly differently. In this patch, the following differences are
relevant:
1. GCC recognizes comments that say "fall through" as annotations, clang
   doesn't
2. GCC doesn't warn on "case N: foo(); default: break;", clang does
3. GCC doesn't warn when the case contains a switch, but falls through
   the outer case.

I will enable the warning separately in a follow-up patch so that it can
be cleanly reverted if necessary.

Reviewers: alexfh, rsmith, lattner, rtrieu, EricWF, bollu

Differential Revision: https://reviews.llvm.org/D53950

llvm-svn: 345882
2018-11-01 19:54:45 +00:00
Erich Keane 19a8adc9bd Implement Function Multiversioning for Non-ELF Systems.
Similar to how ICC handles CPU-Dispatch on Windows, this patch uses the
resolver function directly to forward the call to the proper function.
This is not nearly as efficient as IFuncs of course, but is still quite
useful for large functions specifically developed for certain
processors.

This is unfortunately still limited to x86, since it depends on
__builtin_cpu_supports and __builtin_cpu_is, which are x86 builtins.

The naming for the resolver/forwarding function for cpu-dispatch was
taken from ICC's implementation, which uses the unmodified name for this
(no mangling additions).  This is possible, since cpu-dispatch uses '.A'
for the 'default' version.

In 'target' multiversioning, this function keeps the '.resolver'
extension in order to keep the default function keeping the default
mangling.

Change-Id: I4731555a39be26c7ad59a2d8fda6fa1a50f73284

Differential Revision: https://reviews.llvm.org/D53586

llvm-svn: 345298
2018-10-25 18:57:19 +00:00
Hans Wennborg b4278895a4 Revert r323281 "Adjust MaxAtomicInlineWidth for i386/i486 targets."
As reported on http://lists.llvm.org/pipermail/cfe-dev/2018-August/058760.html,
this broke i386-freebsd11 due to its lack of atomic 64 bit primitives.

While that's not really this commit's fault, let's revert back to the old
behaviour until this can be fixed. This means generating cmpxchg8b etc for i386
and i486 which don't technically support those, but that's been the behaviour
for a long time, so a little longer probably doesn't hurt that much.

> Adjust MaxAtomicInlineWidth for i386/i486 targets.
>
> This is to fix the bug reported in https://bugs.llvm.org/show_bug.cgi?id=34347#c6.
> Currently, all  MaxAtomicInlineWidth of x86-32 targets are set to 64. However,
> i386 doesn't support any cmpxchg related instructions. i486 only supports cmpxchg.
> So in this patch MaxAtomicInlineWidth is reset as follows:
> For i386, the MaxAtomicInlineWidth should be 0 because no cmpxchg is supported.
> For i486, the MaxAtomicInlineWidth should be 32 because it supports cmpxchg.
> For others 32 bits x86 cpu, the MaxAtomicInlineWidth should be 64 because of cmpxchg8b.
>
> Differential Revision: https://reviews.llvm.org/D42154

llvm-svn: 340666
2018-08-24 22:46:33 +00:00
Chandler Carruth ae0cafece8 [x86/retpoline] Split the LLVM concept of retpolines into separate
subtarget features for indirect calls and indirect branches.

This is in preparation for enabling *only* the call retpolines when
using speculative load hardening.

I've continued to use subtarget features for now as they continue to
seem the best fit given the lack of other retpoline like constructs so
far.

The LLVM side is pretty simple. I'd like to eventually get rid of the
old feature, but not sure what backwards compatibility issues that will
cause.

This does remove the "implies" from requesting an external thunk. This
always seemed somewhat questionable and is now clearly not desirable --
you specify a thunk the same way no matter which set of things are
getting retpolines.

I really want to keep this nicely isolated from end users and just an
LLVM implementation detail, so I've moved the `-mretpoline` flag in
Clang to no longer rely on a specific subtarget feature by that name and
instead to be directly handled. In some ways this is simpler, but in
order to preserve existing behavior I've had to add some fallback code
so that users who relied on merely passing -mretpoline-external-thunk
continue to get the same behavior. We should eventually remove this
I suspect (we have never tested that it works!) but I've not done that
in this patch.

Differential Revision: https://reviews.llvm.org/D51150

llvm-svn: 340515
2018-08-23 06:06:38 +00:00
Fangrui Song 6907ce2f8f Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338291
2018-07-30 19:24:48 +00:00
Sanjin Sijaric 56391d6f84 [ARM64] [Windows] Follow MS X86_64 C++ ABI when passing structs
Summary: Microsoft's C++ object model for ARM64 is the same as that for X86_64.
For example, small structs with non-trivial copy constructors or virtual
function tables are passed indirectly.  Currently, they are passed in registers
when compiled with clang.

Reviewers: rnk, mstorsjo, TomTan, haripul, javed.absar

Reviewed By: rnk, mstorsjo

Subscribers: kristof.beyls, chrib, llvm-commits, cfe-commits

Differential Revision: https://reviews.llvm.org/D49770

llvm-svn: 338076
2018-07-26 22:18:28 +00:00
Erich Keane 3efe00206f Implement cpu_dispatch/cpu_specific Multiversioning
As documented here: https://software.intel.com/en-us/node/682969 and
https://software.intel.com/en-us/node/523346. cpu_dispatch multiversioning
is an ICC feature that provides for function multiversioning.

This feature is implemented with two attributes: First, cpu_specific,
which specifies the individual function versions. Second, cpu_dispatch,
which specifies the location of the resolver function and the list of
resolvable functions.

This is valuable since it provides a mechanism where the resolver's TU
can be specified in one location, and the individual implementions
each in their own translation units.

The goal of this patch is to be source-compatible with ICC, so this
implementation diverges from the ICC implementation in a few ways:
1- Linux x86/64 only: This implementation uses ifuncs in order to
properly dispatch functions. This is is a valuable performance benefit
over the ICC implementation. A future patch will be provided to enable
this feature on Windows, but it will obviously more closely fit ICC's
implementation.
2- CPU Identification functions: ICC uses a set of custom functions to identify
the feature list of the host processor. This patch uses the cpu_supports
functionality in order to better align with 'target' multiversioning.
1- cpu_dispatch function def/decl: ICC's cpu_dispatch requires that the function
marked cpu_dispatch be an empty definition. This patch supports that as well,
however declarations are also permitted, since the linker will solve the
issue of multiple emissions.

Differential Revision: https://reviews.llvm.org/D47474

llvm-svn: 337552
2018-07-20 14:13:28 +00:00
Reid Kleckner 89fbd55145 Revert r333791 "Cap "voluntary" vector alignment at 16 for all Darwin platforms."
Adding __attribute__((aligned(32))) to __m256 breaks the implementation
of _mm256_loadu_ps on Windows. On Windows, alignment attributes have
higher precedence than packing attributes.

We also might want to carefully consider the consequences of changing
our vector typedefs, since many users copy them and invent their own
new, non-Intel specific vector type names.

llvm-svn: 333958
2018-06-04 21:39:20 +00:00
John McCall 280c656031 Cap "voluntary" vector alignment at 16 for all Darwin platforms.
This fixes two major problems:
- We were not capping vector alignment as desired on 32-bit ARM.
- We were using different alignments based on the AVX settings on
  Intel, so we did not have a consistent ABI.

This is an ABI break, but we think we can get away with it because
vectors tend to be used mostly in inline code (which is why not having
a consistent ABI has not proven disastrous on Intel).

Intel's AVX types are specified as having 32-byte / 64-byte alignment,
so align them explicitly instead of relying on the base ABI rule.
Note that this sort of attribute is stripped from template arguments
in template substitution, so there's a possibility that code templated
over vectors will produce inadequately-aligned objects.  The right
long-term solution for this is for alignment attributes to be
interpreted as true qualifiers and thus preserved in the canonical type.

llvm-svn: 333791
2018-06-01 21:34:26 +00:00