Commit Graph

292 Commits

Author SHA1 Message Date
Diogo N. Sampaio
8786a946d8 [ARM] Add command-line option for SB
SB (Speculative Barrier) is only mandatory from 8.5
onwards but is optional from Armv8.0-A. This patch adds a command
line option to enable SB, as it was previously only possible to
enable by selecting -march=armv8.5-a.

This patch also renames FeatureSpecRestrict to FeatureSB.

Reviewed By: olista01, LukeCheeseman

Differential Revision: https://reviews.llvm.org/D55990

llvm-svn: 350299
2019-01-03 12:09:12 +00:00
Oliver Stannard
382c935c42 [ARM][v8.5A] Add speculation barrier to ARM & Thumb instruction sets
This is a new barrier which limits speculative execution of the
instructions following it.

Patch by Pablo Barrio!

Differential revision: https://reviews.llvm.org/D52477

llvm-svn: 343213
2018-09-27 13:41:14 +00:00
Oliver Stannard
7c3c4baa3f [ARM/AArch64][v8.5A] Add Armv8.5-A target
This patch allows targeting Armv8.5-A, adding the architecture to
tablegen and setting the options to be identical to Armv8.4-A for the
time being. Subsequent patches will add support for the different
features included in the Armv8.5-A Reference Manual.

Patch by Pablo Barrio!

Differential revision: https://reviews.llvm.org/D52470

llvm-svn: 343102
2018-09-26 12:48:21 +00:00
Evandro Menezes
c62ab61173 [ARM] Refactor Exynos feature set (NFC)
Since all Exynos processors share the same feature set, fold them in the
implied fatures list for the subtarget.

llvm-svn: 342583
2018-09-19 19:43:23 +00:00
Tim Northover
c15d47bb01 ARM: align loops to 4 bytes on Cortex-M3 and Cortex-M4.
The Technical Reference Manuals for these two CPUs state that branching
to an unaligned 32-bit instruction incurs an extra pipeline reload
penalty. That's bad.

This also enables the optimization at -Os since it costs on average one
byte per loop in return for 1 cycle per iteration, which is pretty good
going.

llvm-svn: 342127
2018-09-13 10:28:05 +00:00
Bernard Ogden
b828bb2a15 [ARM/AArch64] Support FP16 +fp16fml instructions
Add +fp16fml feature for new FP16 instructions, which are a
mandatory part of FP16 from v8.4-A and an optional part of FP16
from v8.2-A. It doesn't seem to be possible to model this in
LLVM, but the relationship between the options is handled by
the related clang patch.

In keeping with what I think is the usual practice, the fp16fml
extension is accepted regardless of base architecture version.

Builds on/replaces Sjoerd Meijer's patch to add these instructions at
https://reviews.llvm.org/D49839.

Differential Revision: https://reviews.llvm.org/D50228

llvm-svn: 340013
2018-08-17 11:29:49 +00:00
Evandro Menezes
9a92fe0c9e [ARM] Replace processor check with feature
Add new feature, `FeatureUseWideStrideVFP`, that replaces the need for a
processor check.  Otherwise, NFC.

llvm-svn: 339354
2018-08-09 16:13:24 +00:00
Evandro Menezes
fcca45f0dd [ARM] Add new target feature to fuse literal generation
This feature enables the fusion of such operations on Cortex A57 and Cortex
A72, as recommended in their Software Optimisation Guides, sections 4.14 and
4.11, respectively.

Differential revision: https://reviews.llvm.org/D49563

llvm-svn: 338147
2018-07-27 18:16:47 +00:00
Evandro Menezes
fffa9b5897 [ARM] Add new feature to enable optimizing the VFP registers
Enable the optimization of operations on DPR and SPR via a feature instead
of checking the target.

Differential revision: https://reviews.llvm.org/D49463

llvm-svn: 337575
2018-07-20 16:49:28 +00:00
Tim Northover
097a3e3d95 ARM: deduplicate hard-float detection code. NFC.
ARMSubtarget had a copy/pasted block to determine whether the target was
hard-float, but it just delegated to triple features anyway so it's better at
the TargetMachine level.

llvm-svn: 337384
2018-07-18 12:36:25 +00:00
Sjoerd Meijer
195e904002 [ARM][AArch64] Armv8.4-A Enablement
Initial patch adding assembly support for Armv8.4-A.

Besides adding v8.4 as a supported architecture to the usual places, this also
adds target features for the different crypto algorithms. Armv8.4-A introduced
new crypto algorithms, made them optional, and allows different combinations:

- none of the v8.4 crypto functions are supported, which is independent of the
  implementation of the Armv8.0 SHA1 and SHA2 instructions.
- the v8.4 SHA512 and SHA3 support is implemented, in this case the Armv8.0
  SHA1 and SHA2 instructions must also be implemented.
- the v8.4 SM3 and SM4 support is implemented, which is independent of the
  implementation of the Armv8.0 SHA1 and SHA2 instructions.
- all of the v8.4 crypto functions are supported, in this case the Armv8.0 SHA1
  and SHA2 instructions must also be implemented.

The v8.4 crypto instructions are added to AArch64 only, and not AArch32,
and are made optional extensions to Armv8.2-A.

The user-facing Clang options will map on these new target features, their
naming will be compatible with GCC and added in follow-up patches.

The Armv8.4-A instruction sets can be downloaded here:
https://developer.arm.com/products/architecture/a-profile/exploration-tools

Differential Revision: https://reviews.llvm.org/D48625

llvm-svn: 335953
2018-06-29 08:43:19 +00:00
David Green
21a2973cc4 [ARM] Enable useAA() for the in-order Cortex-R52
This option allows codegen (such as DAGCombine or MI scheduling) to use alias
analysis information, which can help with the codegen on in-order cpu's,
especially machine scheduling. Here I have done things the same way as AArch64,
adding a subtarget feature to enable this for specific cores, and enabled it for
the R52 where we have a schedule to make use of it.

Differential Revision: https://reviews.llvm.org/D48074

llvm-svn: 335249
2018-06-21 15:48:29 +00:00
Adrian Prantl
5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Sam Parker
98727bc261 [ARM] Armv8-R DFB instruction
Implement MC support for the Armv8-R 'Data Full Barrier' instruction.

Differential Revision: https://reviews.llvm.org/D41430

llvm-svn: 321256
2017-12-21 11:17:49 +00:00
Matthias Braun
a4852d2c19 X86/AArch64/ARM: Factor out common sincos_stret logic; NFCI
Note:
- X86ISelLowering: setLibcallName(SINCOS) was superfluous as
  InitLibcalls() already does it.
- ARMISelLowering: Setting libcallnames for sincos/sincosf seemed
  superfluous as in the darwin case it wouldn't be used while for all
  other cases InitLibcalls already does it.

llvm-svn: 321036
2017-12-18 23:19:42 +00:00
David Blaikie
b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Evgeniy Stepanov
76d5ac4906 [arm] Fix Unnecessary reloads from GOT.
Summary:
This fixes PR35221.
Use pseudo-instructions to let MachineCSE hoist global address computation.

Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D39871

llvm-svn: 318081
2017-11-13 20:45:38 +00:00
Sam Parker
b036757f3d [ARM] Reverse PostRASched subtarget feature logic
Replace the UsePostRAScheduler SubtargetFeature with
DisablePostRAScheduler, which is then used by Swift and Cyclone.
This patch maintains enabling PostRA scheduling for other Thumb2
capable cores and/or for functions which are being compiled in Arm
mode.

Differential Revision: https://reviews.llvm.org/D37055

llvm-svn: 312226
2017-08-31 08:57:51 +00:00
Diana Picus
c9f29c62cc [ARM] GlobalISel: Select globals in PIC mode
Support the selection of G_GLOBAL_VALUE in the PIC relocation model. For
simplicity we use the same pseudoinstructions for both Darwin and ELF:
(MOV|LDRLIT)_ga_pcrel(_ldr).

This is new for ELF, so it requires a small update to the ARM pseudo
expansion pass to make sure it adds the correct constant pool modifier
and add-current-address in the case of ELF.

Differential Revision: https://reviews.llvm.org/D36507

llvm-svn: 311992
2017-08-29 09:47:55 +00:00
Joerg Sonnenberger
0f76a35c5e Fix ARMv4 support
ARMv4 doesn't support the "BX" instruction, which has been introduced
with ARMv4t. Adjust the call lowering and tail call implementation
accordingly.

Further changes are necessary to ensure that presence of the v4t feature
is correctly set. Most importantly, the "generic" CPU for thumb-*
triples should include ARMv4t, since thumb mode without thumb support
would naturally be pointless.

Add a couple of asserts to ensure thumb instructions are not emitted
without CPU support.

Differential Revision: https://reviews.llvm.org/D37030

llvm-svn: 311921
2017-08-28 20:20:47 +00:00
Sam Parker
b252ffd2cc [ARM][AArch64] Cortex-A75 and Cortex-A55 support
This patch introduces support for Cortex-A75 and Cortex-A55, Arm's
latest big.LITTLE A-class cores. They implement the ARMv8.2-A
architecture, including the cryptography and RAS extensions, plus
the optional dot product extension. They also implement the RCpc
AArch64 extension from ARMv8.3-A.

Cortex-A75:
https://developer.arm.com/products/processors/cortex-a/cortex-a75

Cortex-A55:
https://developer.arm.com/products/processors/cortex-a/cortex-a55

Differential Revision: https://reviews.llvm.org/D36667

llvm-svn: 311316
2017-08-21 08:43:06 +00:00
Sam Parker
04a7db5915 [ARM] Add PostRAScheduler option
This patch adds the option to allow also using the PostRA scheduler,
which brings the ARM backend inline with AArch64 targets. The
SchedModel can also set 'PostRAScheduler', as the R52 does, so also
query this property in the overridden function.

Differential Revision: https://reviews.llvm.org/D36866

llvm-svn: 311162
2017-08-18 14:27:51 +00:00
Quentin Colombet
61d71a138b Reapply "[GlobalISel] Remove the GISelAccessor API."
This reverts commit r310425, thus reapplying r310335 with a fix for link
issue of the AArch64 unittests on Linux bots when BUILD_SHARED_LIBS is ON.

Original commit message:
[GlobalISel] Remove the GISelAccessor API.

Its sole purpose was to avoid spreading around ifdefs related to
building global-isel. Since r309990, GlobalISel is not optional anymore,
thus, we can get rid of this mechanism all together.

NFC.

----
The fix for the link issue consists in adding the GlobalISel library in
the list of dependencies for the AArch64 unittests. This dependency
comes from the use of AArch64Subtarget that needs to know how
to destruct the GISel related APIs when being detroyed.

Thanks to Bill Seurer and Ahmed Bougacha for helping me reproducing and
understand the problem.

llvm-svn: 310969
2017-08-15 22:31:51 +00:00
Sjoerd Meijer
7426c97bc6 [ARM] Assembler support for the ARMv8.2a dot product instructions
Commit r310480 added the AArch64 ARMv8.2a dot product instructions;
this adds the AArch32 instructions.

Differential Revision: https://reviews.llvm.org/D36575

llvm-svn: 310701
2017-08-11 09:52:30 +00:00
Sam Parker
9d95764c3b [ARM][AArch64] ARMv8.3-A enablement
The beta ARMv8.3 ISA specifications have been released for AArch64
and AArch32, these can be found at:
https://developer.arm.com/products/architecture/a-profile/exploration-tools

An introduction to this architecture update can be found at:
https://community.arm.com/processors/b/blog/posts/armv8-a-architecture-2016-additions

This patch is the first in a series which will add ARM v8.3-A support
in LLVM and Clang. It adds the necessary changes that create targets
for both the ARM and AArch64 backends.

Differential Revision: https://reviews.llvm.org/D36514

llvm-svn: 310561
2017-08-10 09:41:00 +00:00
Quentin Colombet
8dd90fb54b Revert "[GlobalISel] Remove the GISelAccessor API."
This reverts commit r310115.

It causes a linker failure for the one of the unittests of AArch64 on one
of the linux bot:
http://lab.llvm.org:8011/builders/clang-ppc64le-linux-multistage/builds/3429

: && /home/fedora/gcc/install/gcc-7.1.0/bin/g++   -fPIC
-fvisibility-inlines-hidden -Werror=date-time -std=c++11 -Wall -W
-Wno-unused-parameter -Wwrite-strings -Wcast-qual
-Wno-missing-field-initializers -pedantic -Wno-long-long
-Wno-maybe-uninitialized -Wdelete-non-virtual-dtor -Wno-comment
-ffunction-sections -fdata-sections -O2
-L/home/fedora/gcc/install/gcc-7.1.0/lib64 -Wl,-allow-shlib-undefined
-Wl,-O3 -Wl,--gc-sections
unittests/Target/AArch64/CMakeFiles/AArch64Tests.dir/InstSizes.cpp.o  -o
unittests/Target/AArch64/AArch64Tests
lib/libLLVMAArch64CodeGen.so.6.0.0svn lib/libLLVMAArch64Desc.so.6.0.0svn
lib/libLLVMAArch64Info.so.6.0.0svn lib/libLLVMCodeGen.so.6.0.0svn
lib/libLLVMCore.so.6.0.0svn lib/libLLVMMC.so.6.0.0svn
lib/libLLVMMIRParser.so.6.0.0svn lib/libLLVMSelectionDAG.so.6.0.0svn
lib/libLLVMTarget.so.6.0.0svn lib/libLLVMSupport.so.6.0.0svn -lpthread
lib/libgtest_main.so.6.0.0svn lib/libgtest.so.6.0.0svn -lpthread
-Wl,-rpath,/home/buildbots/ppc64le-clang-multistage-test/clang-ppc64le-multistage/stage1/lib
&& :
unittests/Target/AArch64/CMakeFiles/AArch64Tests.dir/InstSizes.cpp.o:(.toc+0x0):
undefined reference to `vtable for llvm::LegalizerInfo'
unittests/Target/AArch64/CMakeFiles/AArch64Tests.dir/InstSizes.cpp.o:(.toc+0x8):
undefined reference to `vtable for llvm::RegisterBankInfo'

The particularity of this bot is that it is built with
BUILD_SHARED_LIBS=ON

However, I was not able to reproduce the problem so far.
Reverting to unblock the bot.

llvm-svn: 310425
2017-08-08 22:22:30 +00:00
Quentin Colombet
c046208c52 [GlobalISel] Remove the GISelAccessor API.
Its sole purpose was to avoid spreading around ifdefs related to
building global-isel. Since r309990, GlobalISel is not optional anymore,
thus, we can get rid of this mechanism all together.

NFC.

llvm-svn: 310115
2017-08-04 20:15:46 +00:00
Strahinja Petrovic
25e9e1b866 [ARM] Add the option to directly access TLS pointer
This patch enables choice for accessing thread local
storage pointer (like '-mtp' in gcc).

Differential Revision: https://reviews.llvm.org/D34408

llvm-svn: 309381
2017-07-28 12:54:57 +00:00
Florian Hahn
e3583bdf91 [ARM] Add use-misched feature, to enable the MachineScheduler.
Summary:
This change makes it easier to experiment with the MachineScheduler in
the ARM backend and also makes it very explicit which CPUs use the
MachineScheduler (currently only swift and cyclone).



Reviewers: MatzeB, t.p.northover, javed.absar

Reviewed By: MatzeB

Subscribers: aemerson, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D35935

llvm-svn: 309316
2017-07-27 19:56:44 +00:00
John Brawn
75d76e5e95 [ARM] Improve if-conversion for M-class CPUs without branch predictors
The current heuristic in isProfitableToIfCvt assumes we have a branch predictor,
and so gives the wrong answer in some cases when we don't. This patch adds a
subtarget feature to indicate that a subtarget has no branch predictor, and
changes the heuristic in isProfitableToiIfCvt when it's present. This gives a
slight overall improvement in a set of embedded benchmarks on Cortex-M4 and
Cortex-M33.

Differential Revision: https://reviews.llvm.org/D34398

llvm-svn: 306547
2017-06-28 14:11:15 +00:00
Florian Hahn
b489e56ae2 [ARM] Add macro fusion for AES instructions.
Summary:
This patch adds a macro fusion using CodeGen/MacroFusion.cpp to pair AES
instructions back to back and adds FeatureFuseAES to enable the feature.

Reviewers: evandro, javed.absar, rengolin, t.p.northover

Reviewed By: javed.absar

Subscribers: aemerson, mgorny, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D34142

llvm-svn: 305988
2017-06-22 09:39:36 +00:00
Javed Absar
4ae7e81233 [ARM] Cortex-A57 scheduling model for ARM backend (AArch32)
This patch implements the Cortex-A57 scheduling model.
The main code is in ARMScheduleA57.td, ARMScheduleA57WriteRes.td.
Small changes in cpp,.h files to support required scheduling predicates.

Scheduling model implemented according to:
 http://infocenter.arm.com/help/topic/com.arm.doc.uan0015b/Cortex_A57_Software_Optimization_Guide_external.pdf.

Patch by : Andrew Zhogin (submitted on his behalf, as requested).
Rewiewed by: Renato Golin, Diana Picus, Javed Absar, Kristof Beyls.
Differential Revision: https://reviews.llvm.org/D28152

llvm-svn: 304530
2017-06-02 08:53:19 +00:00
Diana Picus
7c6dee9f16 [ARM] Rename HW div feature to HW div Thumb. NFCI.
The hardware div feature refers only to Thumb, but because of its name
it is tempting to use it to check for hardware division in general,
which may cause problems in ARM mode. See https://reviews.llvm.org/D32005.

This patch adds "Thumb" to its name, to make its scope clear. One
notable place where I haven't made the change is in the feature flag
(used with -mattr), which is still hwdiv. Changing it would also require
changes in a lot of tests, including clang tests, and it doesn't seem
like it's worth the effort.

Differential Revision: https://reviews.llvm.org/D32160

llvm-svn: 300827
2017-04-20 09:38:25 +00:00
Yi Kong
60b5a1cd17 Revert "Revert "[ARM] Add Kryo to available targets""
This reverts commit dc9458d5a747a02a9a8f198b84c2b92a6939a8dd.

Added missing case for PreISelOperandLatencyAdjustment.

llvm-svn: 299724
2017-04-06 22:47:47 +00:00
Yi Kong
5e7059b702 Revert "[ARM] Add Kryo to available targets"
This reverts commit 942d6e6f58bf7e63810dd7cbcbce1fdfa5ebc6d4.

Build breakage.

llvm-svn: 299689
2017-04-06 19:16:14 +00:00
Yi Kong
2b622b1fc1 [ARM] Add Kryo to available targets
Summary:
Host CPU detection now supports Kryo, so we need to recognize it in ARM
target.

Reviewers: mcrosier, t.p.northover, rengolin, echristo, srhines

Reviewed By: t.p.northover, echristo

Subscribers: aemerson

Differential Revision: https://reviews.llvm.org/D31775

llvm-svn: 299674
2017-04-06 18:10:08 +00:00
Sanne Wouda
2409c6403d [ARM] [Assembler] Support negative immediates for A32, T32 and T16
Summary:
To support negative immediates for certain arithmetic instructions, the
instruction is converted to the inverse instruction with a negated (or inverted)
immediate. For example, "ADD r0, r1, #FFFFFFFF" cannot be encoded as an ADD
instruction.  However, "SUB r0, r1, #1" is equivalent.

These conversions are different from instruction aliases.  An alias maps
several assembler instructions onto one encoding.  A conversion, however, maps
an *invalid* instruction--e.g. with an immediate that cannot be represented in
the encoding--to a different (but equivalent) instruction.

Several instructions with negative immediates were being converted already, but
this was not systematically tested, nor did it cover all instructions.

This patch implements all possible substitutions for ARM, Thumb1 and
Thumb2 assembler and adds tests.  It also adds a feature flag
(-mattr=+no-neg-immediates) to turn these substitutions off.  This is
helpful for users who want their code to assemble to exactly what they
wrote.

Reviewers: t.p.northover, rovka, samparker, javed.absar, peter.smith, rengolin

Reviewed By: javed.absar

Subscribers: aadg, aemerson, llvm-commits

Differential Revision: https://reviews.llvm.org/D30571

llvm-svn: 298380
2017-03-21 14:59:17 +00:00
Sam Parker
58af0c55d2 [ARM] Replace HasT2ExtractPack with HasDSP
Removed the HasT2ExtractPack feature and replaced its references
with HasDSP. This then allows the Thumb2 extend instructions to be
selected for ARMv8M +dsp. These instruction descriptions have also
been refactored and more target tests have been added for their isel.

Differential Revision: https://reviews.llvm.org/D29623

llvm-svn: 295452
2017-02-17 15:42:44 +00:00
Matthias Braun
2bef2a08c0 Fix syntax error
llvm-svn: 294678
2017-02-10 00:09:20 +00:00
Matthias Braun
62e1e8531b ARMSubtarget.h: Change to one line per enum element; NFC
Change syntax to have enum elements sorted alphabetically and one per
line as that is more merge/cherry pick friendly.

llvm-svn: 294677
2017-02-10 00:06:44 +00:00
George Burgess IV
ccf11c2f9f [ARM] Add support for armv7ve triple in llvm (PR31358).
Gcc supports target armv7ve which is armv7-a with virtualization
extensions. This change adds support for this in llvm for gcc
compatibility.

Also remove redundant FeatureHWDiv, FeatureHWDivARM for a few models as
this is specified automatically by FeatureVirtualization.

Patch by Manoj Gupta.

Differential Revision: https://reviews.llvm.org/D29472

llvm-svn: 294661
2017-02-09 23:29:14 +00:00
Eugene Zelenko
e79c077ef9 [ARM] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 293348
2017-01-27 23:58:02 +00:00
Prakhar Bahuguna
52a7dd7d78 [ARM] Implement execute-only support in CodeGen
This implements execute-only support for ARM code generation, which
prevents the compiler from generating data accesses to code sections.
The following changes are involved:

* Add the CodeGen option "-arm-execute-only" to the ARM code generator.
* Add the clang flag "-mexecute-only" as well as the GCC-compatible
  alias "-mpure-code" to enable this option.
* When enabled, literal pools are replaced with MOVW/MOVT instructions,
  with VMOV used in addition for floating-point literals. As the MOVT
  instruction is required, execute-only support is only available in
  Thumb mode for targets supporting ARMv8-M baseline or Thumb2.
* Jump tables are placed in data sections when in execute-only mode.
* The execute-only text section is assigned section ID 0, and is
  marked as unreadable with the SHF_ARM_PURECODE flag with symbol 'y'.
  This also overrides selection of ELF sections for globals.

llvm-svn: 289784
2016-12-15 07:59:08 +00:00
Diana Picus
22274934f4 [ARM] Add plumbing for GlobalISel
Add GlobalISel skeleton, up to the point where we can select a ret void.

llvm-svn: 286573
2016-11-11 08:27:37 +00:00
Javed Absar
85874a9360 [ARM]: Assign cost of scaling used in addressing mode for ARM cores
This patch assigns cost of the scaling used in addressing.
On many ARM cores, a negated register offset takes longer than a
non-negated register offset, in a register-offset addressing mode.

For instance:

LDR R0, [R1, R2 LSL #2]
LDR R0, [R1, -R2 LSL #2]

Above, (1) takes less cycles than (2).

By assigning appropriate scaling factor cost, we enable the LLVM
to make the right trade-offs in the optimization and code-selection phase.

Differential Revision: http://reviews.llvm.org/D24857

Reviewers: jmolloy, rengolin
llvm-svn: 284127
2016-10-13 14:57:43 +00:00
Reid Kleckner
bdfc05ff93 Re-land "[Thumb] Save/restore high registers in Thumb1 pro/epilogues"
Reverts r283938 to reinstate r283867 with a fix.

The original change had an ArrayRef referring to a destroyed temporary
initializer list. Use plain C arrays instead.

llvm-svn: 283942
2016-10-11 21:14:03 +00:00
Reid Kleckner
f4876beb2b Revert "[Thumb] Save/restore high registers in Thumb1 pro/epilogues"
This reverts r283867.

This appears to be an infinite loop:

    while (HiRegToSave != AllHighRegs.end() && CopyReg != AllCopyRegs.end()) {
      if (HiRegsToSave.count(*HiRegToSave)) {
        ...

        CopyReg = findNextOrderedReg(++CopyReg, CopyRegs, AllCopyRegs.end());
        HiRegToSave =
            findNextOrderedReg(++HiRegToSave, HiRegsToSave, AllHighRegs.end());
      }
    }

llvm-svn: 283938
2016-10-11 20:54:41 +00:00
Oliver Stannard
d2083fb356 [Thumb] Save/restore high registers in Thumb1 pro/epilogues
The high registers are not allocatable in Thumb1 functions, but they
could still be used by inline assembly, so we need to save and restore
the callee-saved high registers (r8-r11) in the prologue and epilogue.

This is complicated by the fact that the Thumb1 push and pop
instructions cannot access these registers. Therefore, we have to move
them down into low registers before pushing, and move them back after
popping into low registers.

In most functions, we will have low registers that are also being
pushed/popped, which we can use as the temporary registers for
saving/restoring the high registers. However, this is not guaranteed, so
we may need to push some extra low registers to ensure that the high
registers can be saved/restored. For correctness, it would be sufficient
to use just one low register, but if we have enough low registers
available then we only need one push/pop instruction, rather than one
per high register.

We can also use the argument/return registers when they are not live,
and the link register when saving (but not restoring), reducing the
number of extra registers we need to push.

There are still a few extreme edge cases where we need two push/pop
instructions, because not enough low registers can be made live in the
prologue or epilogue.

In addition to the regression tests included here, I've also tested this
using a script to generate functions which clobber different
combinations of registers, have different numbers of argument and return
registers (including variadic arguments), allocate different fixed sized
objects on the stack, and do or don't use variable sized allocas and the
__builtin_return_address intrinsic (all of which affect the available
registers in the prologue and epilogue). I ran these functions in a test
harness which verifies that all of the callee-saved registers are
correctly preserved.

Differential Revision: https://reviews.llvm.org/D24228

llvm-svn: 283867
2016-10-11 10:12:25 +00:00
Javed Absar
fb4b6e8db9 [ARM]: Add Cortex-R52 target to LLVM
This patch adds Cortex-R52, the new ARM real-time processor, to LLVM. 
Cortex-R52 implements the ARMv8-R architecture.

llvm-svn: 283542
2016-10-07 12:06:40 +00:00
Dean Michael Berris
4640154446 [XRay] ARM 32-bit no-Thumb support in LLVM
This is a port of XRay to ARM 32-bit, without Thumb support yet. The XRay instrumentation support is moving up to AsmPrinter.
This is one of 3 commits to different repositories of XRay ARM port. The other 2 are:

https://reviews.llvm.org/D23932 (Clang test)
https://reviews.llvm.org/D23933 (compiler-rt)

Differential Revision: https://reviews.llvm.org/D23931

llvm-svn: 281878
2016-09-19 00:54:35 +00:00