Commit Graph

7800 Commits

Author SHA1 Message Date
Renato Golin f5dd1dacb6 Add aliases for VAND imm to VBIC ~imm
On ARM NEON, VAND with immediate (16/32 bits) is an alias to VBIC ~imm with
the same type size. Adding that logic to the parser, and generating VBIC
instructions from VAND asm files.

This patch also fixes the validation routines for NEON splat immediates which
were wrong.

Fixes PR20702.

llvm-svn: 218450
2014-09-25 11:31:24 +00:00
Oliver Stannard 3256b26ef2 [Thumb2] BXJ should be undefined for v7M, v8A
The Thumb2 BXJ instruction (Branch and Exchange Jazelle) is not
defined for v7M or v8A. It is defined for all other Thumb2-supporting
architectures (v6T2, v7A and v7R).

llvm-svn: 218445
2014-09-25 10:02:05 +00:00
Moritz Roth f5d0c7c2c0 [Thumb] Make load/store optimizer less conservative.
If it's safe to clobber the condition flags, we can do a few extra things:
it's then possible to reset the base register writeback using a SUBS, so
we can try to merge even if the base register isn't dead after the merged
instruction.

This is effectively a (heavily bug-fixed) rewrite of r208992.

llvm-svn: 218386
2014-09-24 16:35:50 +00:00
Oliver Stannard 1ae8b476f4 [Thumb] 32-bit encodings of 'cps' are not valid for v7M
v7M only allows the 16-bit encoding of the 'cps' (Change Processor
State) instruction, and does not have the 32-bit encoding which is
valid from v6T2 onwards.

llvm-svn: 218382
2014-09-24 14:20:01 +00:00
Robin Morisset dedef3325f Add AtomicExpandPass::bracketInstWithFences, and use it whenever getInsertFencesForAtomic would trigger in SelectionDAGBuilder
Summary:
The goal is to eventually remove all the code related to getInsertFencesForAtomic
in SelectionDAGBuilder as it is wrong (designed for ARM, not really portable, works
mostly by accident because the backends are overly conservative), and repeats the
same logic that goes in emitLeading/TrailingFence.

In this patch, I make AtomicExpandPass insert the fences as it knows better
where to put them. Because this requires getting the fences and not just
passing an IRBuilder around, I had to change the return type of
emitLeading/TrailingFence.
This code only triggers on ARM for now. Because it is earlier in the pipeline
than SelectionDAGBuilder, it triggers and lowers atomic accesses to atomic so
SelectionDAGBuilder does not add barriers anymore on ARM.

If this patch is accepted I plan to implement emitLeading/TrailingFence for all
backends that setInsertFencesForAtomic(true), which will allow both making them
less conservative and simplifying SelectionDAGBuilder once they are all using
this interface.

This should not cause any functionnal change so the existing tests are used
and not modified.

Test Plan: make check-all, benefits from existing tests of atomics on ARM

Reviewers: jfb, t.p.northover

Subscribers: aemerson, llvm-commits

Differential Revision: http://reviews.llvm.org/D5179

llvm-svn: 218329
2014-09-23 20:31:14 +00:00
Robin Morisset a7b357fed1 Just add a fixme about a possibly faster implementation of some atomic loads on some ARM processors
llvm-svn: 218326
2014-09-23 18:33:21 +00:00
Lang Hames d5f496d57c [MCJIT] Nuke MachineRelocation and MachineCodeEmitter. Now that the old JIT is
gone they're no longer needed.

llvm-svn: 218320
2014-09-23 18:08:47 +00:00
Quentin Colombet 17799fedb7 [ARM] Do not perform a tail call when the caller returns several values.
The fix is slightly different then x86 (see r216117) because the number of values
attached to a return can vary even for a single returned value (e.g., f64 yields
two returned values).

<rdar://problem/18352998>

llvm-svn: 218076
2014-09-18 21:17:50 +00:00
Robin Morisset 5349e8e532 Restore "[ARM, Fix] Fix emitLeading/TrailingFence on old ARM processors"
Summary:
This patch was originally in D5304 (I could not find a way to reopen that revision).
It was accepted, commited and broke the build bots because the overloading of
the constructor of ArrayRef for braced initializer lists is not supported by all
toolchains. I then reverted it, and propose this fixed version that uses a plain
C array instead in makeDMB (that array is then converted implicitly to an
ArrayRef, but that is not behind an ifdef). Could someone confirm me whether
initialization lists for plain C arrays are supported by every toolchain used
to build llvm ? Otherwise I can just initialize the array in the old way:
args[0] = ...; .. ; args[5] = ...;

Below is the description of the original patch:
```
I had only tested this code for ARMv7 and ARMv8. This patch adds several
fallback paths if the processor does not support dmb ish:
- dmb sy if a cortex-M with support for dmb
- mcr p15, #0, r0, c7, c10, #5 for ARMv6 (special instruction equivalent to a DMB)
These fallback paths were chosen based on the code for fence seq_cst.

Thanks to luqmana for having noticed this bug.
```

Test Plan: Added more cases to atomic-load-store.ll + make check-all

Reviewers: jfb, t.p.northover, luqmana

Subscribers: llvm-commits, aemerson

Differential Revision: http://reviews.llvm.org/D5386

llvm-svn: 218066
2014-09-18 18:56:04 +00:00
Aaron Ballman 0bb041b5f4 Reverting NFC changes from r218050. Instead, the warning was disabled for GCC in r218059, so these changes are no longer required.
llvm-svn: 218062
2014-09-18 17:34:23 +00:00
Aaron Ballman 11fa97fa32 Fixing a bunch of -Woverloaded-virtual warnings due to hiding getSubtargetImpl from the base class. NFC.
llvm-svn: 218050
2014-09-18 13:27:14 +00:00
Saleem Abdulrasool bfdfb14a8f ARM: prevent crash on ELF directives on COFF
Certain directives are unsupported on Windows (some of which could/should be
supported).  We would not diagnose the use but rather crash during the emission
as we try to access the Target Streamer.  Add an assertion to prevent creating a
NULL reference (which is not permitted under C++) as well as a test to ensure
that we can diagnose the disabled directives.

llvm-svn: 218014
2014-09-18 04:28:29 +00:00
Saleem Abdulrasool 8c61c6c0f9 ARM: use a more precise check for MachO
Rather than relying on support for a specific directive to determine if we are
targeting MachO, explicitly check the output format.

As an additional bonus, cleanup the caret diagnostic for the non-MachO case and
avoid the spurious error caused by not discarding the statement.

llvm-svn: 218012
2014-09-18 03:49:55 +00:00
Robin Morisset bf26f8fd56 Revert "[ARM, Fix] Fix emitLeading/TrailingFence on old ARM processors"
It is breaking the build on the buildbots but works fine on my machine, I revert
while trying to understand what happens (it appears to depend on the compiler used
to build, I probably used a C++11 feature that is not perfectly supported by some
of the buildbots).

This reverts commit feb3176c4d006f99af8b40373abd56215a90e7cc.

llvm-svn: 217973
2014-09-17 18:09:13 +00:00
Robin Morisset 1c8a457575 [ARM, Fix] Fix emitLeading/TrailingFence on old ARM processors
Summary:
I had only tested this code for ARMv7 and ARMv8. This patch adds several
fallback paths if the processor does not support dmb ish:
- dmb sy if a cortex-M with support for dmb
- mcr p15, #0, r0, c7, c10, #5 for ARMv6 (special instruction equivalent to a DMB)
These fallback paths were chosen based on the code for fence seq_cst.

Thanks to luqmana for having noticed this bug.

Test Plan: Added more cases to atomic-load-store.ll + make check-all

Reviewers: jfb, t.p.northover, luqmana

Subscribers: aemerson, llvm-commits

Differential Revision: http://reviews.llvm.org/D5304

llvm-svn: 217965
2014-09-17 17:41:16 +00:00
Richard Trieu 1fbe1a8ba7 | -> ||
No functional change.

llvm-svn: 217934
2014-09-17 01:47:52 +00:00
Robin Morisset 25c8e318e4 [X86] Use the generic AtomicExpandPass instead of X86AtomicExpandPass
This required a new hook called hasLoadLinkedStoreConditional to know whether
to expand atomics to LL/SC (ARM, AArch64, in a future patch Power) or to
CmpXchg (X86).

Apart from that, the new code in AtomicExpandPass is mostly moved from
X86AtomicExpandPass. The main result of this patch is to get rid of that
pass, which had lots of code duplicated with AtomicExpandPass.

llvm-svn: 217928
2014-09-17 00:06:58 +00:00
Moritz Roth eef9f4dc74 ARM load/store optimizer: Don't materialize a new base register with
ADDS/SUBS unless it's safe to clobber the condition flags.

If the merged instructions are in a range where the CPSR is live,
e.g. between a CMP -> Bcc, we can't safely materialize a new base
register.

This problem is quite rare, I couldn't come up with a test case and I've
never actually seen this happen in the tests I'm running - there is a
potential trigger for this in LNT/oggenc (spills being inserted between
a CMP/Bcc), but at the moment this isn't being merged. I'll try to
reduce that into a small test case once I've committed my upcoming patch
to make merging less conservative.

llvm-svn: 217881
2014-09-16 16:25:07 +00:00
Joe Abbey 8e72eb780e ARMAsmBackend uses a factory method to generate binary file format specific
objects.  There were a few FIXMEs in ARMAsmBackend.cpp suggesting the class
definitions should be in a separate file.  Starting with ARMAsmBackend, the
class definition has been put in a header file, and #includes reduced.  Each
sub-type of ARMAsmBackend is now in its own header file.

Derived types have been painted with a different color of bike-shed:

  s/DarwinARMAsmBackend/ARMAsmBackendDarwin/g
  s/ARMWinCOFFAsmBackend/ARMAsmBackendWinCOFF/g
  s/ELFARMAsmBackend/ARMAsmBackendELF/g

Finally, clang-format has been run across ARMAsmBackend.cpp

llvm-svn: 217866
2014-09-16 09:18:23 +00:00
James Molloy a9f47b6bae [ARM] Teach the cost model that cross-class copies are costly.
Cross-class copies being expensive is actually a trait of the microarchitecture, but as I haven't yet seen an example of a microarchitecture where they're cheap it seems best to just enable this by default, covering the non-mcpu build case.

llvm-svn: 217674
2014-09-12 13:29:40 +00:00
Sanjay Patel b653de1ada Rename getMaximumUnrollFactor -> getMaxInterleaveFactor; also rename option names controlling this variable.
"Unroll" is not the appropriate name for this variable. Clang already uses 
the term "interleave" in pragmas and metadata for this.

Differential Revision: http://reviews.llvm.org/D5066

llvm-svn: 217528
2014-09-10 17:58:16 +00:00
Tim Northover ba1d704229 ARM: don't size-reduce STMs using the LR register.
The only Thumb-1 multi-store capable of using LR is the PUSH instruction, which
translates to STMDB, so we shouldn't convert STMIAs.

Patch by Sergey Dmitrouk.

llvm-svn: 217498
2014-09-10 12:53:28 +00:00
Renato Golin 63e27980da ARM: Negative offset support problem
This patch is to permit a negative offset usage for a non frame access.

Patch by Igor Oblakov.

llvm-svn: 217431
2014-09-09 09:57:59 +00:00
Tim Northover c879d06a85 ARM: cover all sub-architecture enumerators to keep compiler happy.
No change in behaviour (hopefully).

llvm-svn: 217233
2014-09-05 07:56:46 +00:00
Aaron Ballman 169eeb913d Silencing a usually-helpful-but-braindead-silly-in-this-case sign mismatch warning with MSVC. NFC.
llvm-svn: 217143
2014-09-04 11:52:24 +00:00
Robin Morisset ed3d48f161 Refactor AtomicExpandPass and add a generic isAtomic() method to Instruction
Summary:
Split shouldExpandAtomicInIR() into different versions for Stores/Loads/RMWs/CmpXchgs.
Makes runOnFunction cleaner (no more redundant checking/casting), and will help moving
the X86 backend to this pass.

This requires a way of easily detecting which instructions are atomic.
I followed the pattern of mayReadFromMemory, mayWriteOrReadMemory, etc.. in making
isAtomic() a method of Instruction implemented by a switch on the opcodes.

Test Plan: make check

Reviewers: jfb

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D5035

llvm-svn: 217080
2014-09-03 21:29:59 +00:00
Robin Morisset a47cb411dc Use target-dependent emitLeading/TrailingFence instead of the target-independent insertLeading/TrailingFence (in AtomicExpandPass)
Fixes two latent bugs:
- There was no fence inserted before expanded seq_cst load (unsound on Power)
- There was only a fence release before seq_cst stores (again unsound, in particular on Power)
    It is not even clear if this is correct on ARM swift processors (where release fences are
    DMB ishst instead of DMB ish). This behaviour is currently preserved on ARM Swift
    as it is not clear whether it is incorrect. I would love to get documentation stating
    whether it is correct or not.
These two bugs were not triggered because Power is not (yet) using this pass, and these
behaviours happen to be (mostly?) working on ARM
(although they completely butchered the semantics of the llvm IR).

See:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075821.html
for an example of the problems that can be caused by the second of these bugs.

I couldn't see a way of fixing these in a completely target-independent way without
adding lots of unnecessary fences on ARM, hence the target-dependent parts of this
patch.

This patch implements the new target-dependent parts only for ARM (the default
of not doing anything is enough for AArch64), other architectures will use this
infrastructure in later patches.

llvm-svn: 217076
2014-09-03 21:01:03 +00:00
Juergen Ributzka 88e32517c4 [FastISel][tblgen] Rename tblgen generated FastISel functions. NFC.
This is the final round of renaming. This changes tblgen to emit lower-case
function names for FastEmitInst_* and FastEmit_*, and updates all its uses
in the source code.

Reviewed by Eric

llvm-svn: 217075
2014-09-03 20:56:59 +00:00
Juergen Ributzka 5b8bb4d7dd [FastISel] Rename public visible FastISel functions. NFC.
This commit renames the following public FastISel functions:
LowerArguments -> lowerArguments
SelectInstruction -> selectInstruction
TargetSelectInstruction -> fastSelectInstruction
FastLowerArguments -> fastLowerArguments
FastLowerCall -> fastLowerCall
FastLowerIntrinsicCall -> fastLowerIntrinsicCall
FastEmitZExtFromI1 -> fastEmitZExtFromI1
FastEmitBranch -> fastEmitBranch
UpdateValueMap -> updateValueMap
TargetMaterializeConstant -> fastMaterializeConstant
TargetMaterializeAlloca -> fastMaterializeAlloca
TargetMaterializeFloatZero -> fastMaterializeFloatZero
LowerCallTo -> lowerCallTo

Reviewed by Eric

llvm-svn: 217074
2014-09-03 20:56:52 +00:00
Eric Christopher b68e25330b Remove resetSubtargetFeatures as it is unused.
llvm-svn: 217071
2014-09-03 20:36:31 +00:00
Benjamin Kramer 8c90fd71f7 Add override to overriden virtual methods, remove virtual keywords.
No functionality change. Changes made by clang-tidy + some manual cleanup.

llvm-svn: 217028
2014-09-03 11:41:21 +00:00
Renato Golin e07a22ac14 Only emit movw on ARMv6T2+
Fix PR18364.

Patch by Dimitry Andric.

llvm-svn: 216989
2014-09-02 22:45:13 +00:00
Eric Christopher 79cc1e3ae7 Reinstate "Nuke the old JIT."
Approved by Jim Grosbach, Lang Hames, Rafael Espindola.

This reinstates commits r215111, 215115, 215116, 215117, 215136.

llvm-svn: 216982
2014-09-02 22:28:02 +00:00
Pete Cooper 1175945710 Change MCSchedModel to be a struct of statically initialized data.
This removes static initializers from the backends which generate this data, and also makes this struct match the other Tablegen generated structs in behaviour

Reviewed by Andy Trick and Chandler C

llvm-svn: 216919
2014-09-02 17:43:54 +00:00
JF Bastien 12cc99eb13 Add missing override on ARMAsmBackend's dtor.
Test Plan: ninja check && ninja clang-test

Subscribers: aemerson

Differential Revision: http://reviews.llvm.org/D5075

llvm-svn: 216912
2014-09-02 16:26:55 +00:00
Renato Golin 92c816c68f Thumb2 M-class MSR instruction support changes
This patch implements a few changes related to the Thumb2 M-class MSR instruction:
 * better handling of unpredictable encodings,
 * recognition of the _g and _nzcvqg variants by the asm parser only if the DSP
   extension is available, preferred output of MSR APSR moves with the _<bits>
   suffix for v7-M.

Patch by Petr Pavlu.

llvm-svn: 216874
2014-09-01 11:25:07 +00:00
Craig Topper 6dc4a8bc2c Fix some cases where StringRef was being passed by const reference. Remove const from some other StringRefs since its implicitly const already.
llvm-svn: 216820
2014-08-30 16:48:02 +00:00
Robin Morisset 039781ef26 Fix typos in comments, NFC
Summary: Just fixing comments, no functional change.

Test Plan: N/A

Reviewers: jfb

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D5130

llvm-svn: 216784
2014-08-29 21:53:01 +00:00
Craig Topper e1d1294853 Simplify creation of a bunch of ArrayRefs by using None, makeArrayRef or just letting them be implicitly created.
llvm-svn: 216525
2014-08-27 05:25:25 +00:00
Yi Kong ebaa150e23 ARM: Add patterns for dbg
llvm-svn: 216451
2014-08-26 12:47:26 +00:00
Chad Rosier e62f365458 [AArch32] Add patterns for VCVT{A,N,P,M}.
Patterns for lowering libm calls to VCVT{A,N,P,M} are also included.
Phabricator Revision: http://reviews.llvm.org/D5033

llvm-svn: 216388
2014-08-25 16:56:33 +00:00
Karthik Bhat 7f33ff7dea Allow vectorization of division by uniform power of 2.
This patch adds support to recognize division by uniform power of 2 and modifies the cost table to vectorize division by uniform power of 2 whenever possible.
Updates Cost model for Loop and SLP Vectorizer.The cost table is currently only updated for X86 backend.
Thanks to Hal, Andrea, Sanjay for the review. (http://reviews.llvm.org/D4971)

llvm-svn: 216371
2014-08-25 04:56:54 +00:00
Craig Topper 4627679cec Use range based for loops to avoid needing to re-mention SmallPtrSet size.
llvm-svn: 216351
2014-08-24 23:23:06 +00:00
Chad Rosier ad7c910ecf Revert "ARM: improve RTABI 4.2 conformance on Linux"
This reverts commit r215862 due to nightly failures.  Will work on getting a
reduced test case, but I wanted to get our bots green in the meantime.

llvm-svn: 216325
2014-08-23 18:29:43 +00:00
Chad Rosier d2959362fb Revert "ARM: mark missing functions from RTABI"
This reverts commit r215863.

llvm-svn: 216324
2014-08-23 18:29:40 +00:00
Reid Kleckner 2d9bb65b3d ARM / x86_64 varargs: Don't save regparms in prologue without va_start
There's no need to do this if the user doesn't call va_start. In the
future, we're going to have thunks that forward these register
parameters with musttail calls, and they won't need these spills for
handling va_start.

Most of the test suite changes are adding va_start calls to existing
tests to keep things working.

llvm-svn: 216294
2014-08-22 21:59:26 +00:00
Quentin Colombet d358e84d9c [ARM] Move the implementation of the target hooks related to copy-related
instruction from ARMInstrInfo to ARMBaseInstrInfo.
That way, thumb mode can also benefit from the advanced copy optimization.

<rdar://problem/12702965>

llvm-svn: 216274
2014-08-22 18:05:22 +00:00
Robin Morisset 59c23cd946 Rename AtomicExpandLoadLinked into AtomicExpand
AtomicExpandLoadLinked is currently rather ARM-specific. This patch is the first of
a group that aim at making it more target-independent. See
http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075873.html
for details

The command line option is "atomic-expand"

llvm-svn: 216231
2014-08-21 21:50:01 +00:00
Moritz Roth dfdda0d41c Thumb1 load/store optimizer: Improve code to materialize new base register.
There are two add-immediate instructions in Thumb1: tADDi8 and tADDi3. Only
the latter supports using different source and destination registers, so
whenever we materialize a new base register (at a certain offset) we'd do
so by moving the base register value to the new register and then adding in
place. This patch changes the code to use a single tADDi3 if the offset is
small enough to fit in 3 bits.

Differential Revision: http://reviews.llvm.org/D5006

llvm-svn: 216193
2014-08-21 17:11:03 +00:00
Jonathan Roelofs 5e98ff967b Add a thread-model knob for lowering atomics on baremetal & single threaded systems
http://reviews.llvm.org/D4984

llvm-svn: 216182
2014-08-21 14:35:47 +00:00
Oliver Stannard 51b1d460cb [ARM] Enable DP copy, load and store instructions for FPv4-SP
The FPv4-SP floating-point unit is generally referred to as
single-precision only, but it does have double-precision registers and
load, store and GPR<->DPR move instructions which operate on them.
This patch enables the use of these registers, the main advantage of
which is that we now comply with the AAPCS-VFP calling convention.
This partially reverts r209650, which added some AAPCS-VFP support,
but did not handle return values or alignment of double arguments in
registers.

This patch also adds tests for Thumb2 code generation for
floating-point instructions and intrinsics, which previously only
existed for ARM.

llvm-svn: 216172
2014-08-21 12:50:31 +00:00
Craig Topper 71b7b68b74 Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.
llvm-svn: 216158
2014-08-21 05:55:13 +00:00
Quentin Colombet 84f15bd1b0 [ARM] Mark VSETLNi32 with the InsertSubreg property and implement the related
target hook.

This patch teaches the compiler that:
dX = VSETLNi32 dY, rZ, imm
is the same as:
dX = INSERT_SUBREG dY, rZ, translateImmToSubIdx(imm)

<rdar://problem/12702965>

llvm-svn: 216143
2014-08-21 00:10:52 +00:00
Jonathan Roelofs 44937d98a3 Lower thumbv4t & thumbv5 lo->lo copies through a push-pop sequence
On pre-v6 hardware, 'MOV lo, lo' gives undefined results, so such copies need to
be avoided. This patch trades simplicity for implementation time at the expense
of performance... As they say: correctness first, then performance.

See http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075998.html for a few
ideas on how to make this better.

llvm-svn: 216138
2014-08-20 23:38:50 +00:00
Quentin Colombet deb82eab3e [ARM] Mark VMOVRRD with the ExtractSubreg property and implement the related
target hook.

This patch teaches the compiler that:
rX, rY = VMOVRRD dZ
is the same as:
rX = EXTRACT_SUBREG dZ, ssub_0
rY = EXTRACT_SUBREG dZ, ssub_1

<rdar://problem/12702965>

llvm-svn: 216132
2014-08-20 22:16:19 +00:00
Yi Kong c655f0c898 ARM: Fix codegen for rbit intrinsic
LLVM generates illegal `rbit r0, #352` instruction for rbit intrinsic.
According to ARM ARM, rbit only takes register as argument, not immediate.
The correct instruction should be rbit <Rd>, <Rm>.

The bug was originally introduced in r211057.

Differential Revision: http://reviews.llvm.org/D4980

llvm-svn: 216064
2014-08-20 10:40:20 +00:00
Alexey Samsonov f17f03e00e Hide two different AlignMode enums in anonymous namespaces. This bug is reported by UBSan.
llvm-svn: 216001
2014-08-19 18:40:39 +00:00
Robin Morisset b155f529fc Make use of isAtLeastRelease/Acquire in the ARM/AArch64 backends
Summary:
Make use of isAtLeastRelease/Acquire in the ARM/AArch64 backends
These helper functions are introduced in D4844.
Depends D4844

Test Plan: make check-all passes

Reviewers: jfb

Subscribers: aemerson, llvm-commits, mcrosier, reames

Differential Revision: http://reviews.llvm.org/D4937

llvm-svn: 215902
2014-08-18 16:48:58 +00:00
Oliver Stannard 12993dd916 [ARM,AArch64] Do not tail-call to an externally-defined function with weak linkage
Externally-defined functions with weak linkage should not be
tail-called on ARM or AArch64, as the AAELF spec requires normal calls
to undefined weak functions to be replaced with a NOP or jump to the
next instruction. The behaviour of branch instructions in this
situation (as used for tail calls) is implementation-defined, so we
cannot rely on the linker replacing the tail call with a return.

llvm-svn: 215890
2014-08-18 12:42:15 +00:00
Tim Northover 26bb14e6a7 TableGen: allow use of uint64_t for available features mask.
ARM in particular is getting dangerously close to exceeding 32 bits worth of
possible subtarget features. When this happens, various parts of MC start to
fail inexplicably as masks get truncated to "unsigned".

Mostly just refactoring at present, and there's probably no way to test.

llvm-svn: 215887
2014-08-18 11:49:42 +00:00
Craig Topper 6230691c91 Revert "Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size."
Getting a weird buildbot failure that I need to investigate.

llvm-svn: 215870
2014-08-18 00:24:38 +00:00
Craig Topper 5229cfd163 Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.
llvm-svn: 215868
2014-08-17 23:47:00 +00:00
Saleem Abdulrasool 3fd996ef5c ARM: mark missing functions from RTABI
Simply indicate the functions that are part of the runtime library that we do
not setup libcalls for.  This is merely for ease of identification.  NFC.

llvm-svn: 215863
2014-08-17 22:51:04 +00:00
Saleem Abdulrasool 017bd57fce ARM: improve RTABI 4.2 conformance on Linux
The set of functions defined in the RTABI was separated for no real reason.
This brings us closer to proper utilisation of the functions defined by the
RTABI.  It also sets the ground for correctly emitting function calls to AEABI
functions on all AEABI conforming platforms.

The previously existing lie on the behaviour of __ldivmod and __uldivmod is
propagated as it is beyond the scope of the change.

The changes to the test are due to the fact that we now use the divmod functions
which return both the quotient and remainder and thus we no longer need to
invoke two functions on Linux (making it closer to EABI's behaviour).

llvm-svn: 215862
2014-08-17 22:51:02 +00:00
Saleem Abdulrasool 740be89f51 ARM: whitespace
Whitespace fix, NFC.

llvm-svn: 215861
2014-08-17 22:50:59 +00:00
Saleem Abdulrasool 78c44725f8 ARM: correct toggling behaviour
This was a thinko.  The intent was to flip the explicit bits that need toggling
rather than all bits.  This would result in incorrect behaviour (which now is
tested).

Thanks to Nico Weber for pointing this out!

llvm-svn: 215846
2014-08-17 19:20:38 +00:00
Nico Weber ae050bb057 arm asm: Let .fpu enable instructions, PR20447.
I'm not very happy with duplicating the fpu->feature mapping in ARMAsmParser.cpp
and in clang's driver. See the bug for a patch that doesn't do that, and the
review thread [1] for why this duplication exists.

1: http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20140811/231052.html
llvm-svn: 215811
2014-08-16 05:37:51 +00:00
Robin Morisset d18cda620c Fix typos in comments
llvm-svn: 215777
2014-08-15 22:17:28 +00:00
Chad Rosier b1bbf6f8ce [AArch32] Add support for FP rounding operations for ARMv8/AArch32.
Phabricator Revision: http://reviews.llvm.org/D4935

llvm-svn: 215772
2014-08-15 21:38:16 +00:00
Moritz Roth 8f3765625e ARM: Fix and re-enable load/store optimizer for Thumb1.
In a previous iteration of the pass, we would try to compensate for
writeback by updating later instructions and/or inserting a SUBS to
reset the base register if necessary.
Since such a SUBS sets the condition flags it's not generally safe to do
this. For now, only merge LDR/STRs if there is no writeback to the base
register (LDM that loads into the base register) or the base register is
killed by one of the merged instructions. These cases are clear wins
both in terms of instruction count and performance.

Also add three new test cases, and update the existing ones accordingly.

llvm-svn: 215729
2014-08-15 17:00:30 +00:00
Moritz Roth 378a43bfe0 ARM load/store optimizer: Compute BaseKill correctly.
This adds some code back that was deleted in r92053. The location of the
last merged memory operation needs to be kept up-to-date since MemOps
may be in a different order to the original instruction stream to
allow merging (since registers need to be in ascending order). Also
simplify the logic to determine BaseKill using findRegisterUseOperandIdx
to use an equivalent function call instead.

llvm-svn: 215728
2014-08-15 17:00:20 +00:00
Juergen Ributzka 5df8603dfd [FastISel][ARM] Fix a think-o in my previous commit (r215682).
We actually need to return the register into which we materialized the constant
and not just "true" for success. This code is currently partially dead, that is
why it didn't trigger any failures yet. Once I change the order of the constant
materialization this code will be fully exercised.

llvm-svn: 215727
2014-08-15 16:59:46 +00:00
Rafael Espindola d610ba99cb Remove HasLEB128.
We already require CFI, so it should be safe to require .leb128 and .uleb128.

llvm-svn: 215712
2014-08-15 14:01:07 +00:00
Tim Northover ee843ef0fa ARM: implement MRS/MSR (banked reg) system instructions.
These are system-only instructions for CPUs with virtualization
extensions, allowing a hypervisor easy access to all of the various
different AArch32 registers.

rdar://problem/17861345

llvm-svn: 215700
2014-08-15 10:47:12 +00:00
Juergen Ributzka 81db58e177 [FastISel][ARM] Fall-back to constant pool loads when materializing an i32 constant.
FastEmit_i won't always succeed to materialize an i32 constant and just fail.
This would trigger a fall-back to SelectionDAG, which is really not necessary.

This fix will first fall-back to a constant pool load to materialize the constant
before giving up for good.

This fixes <rdar://problem/18022633>.

llvm-svn: 215682
2014-08-14 23:29:49 +00:00
Juergen Ributzka a5b083853c [FastISel][ARM] Use MOVT/MOVW if the subtarget requests it.
This change is also in preparation for a future change to make sure that
the constant materialization uses MOVT/MOVW when available and not a load
from the constant pool.

llvm-svn: 215584
2014-08-13 21:42:19 +00:00
Juergen Ributzka 2cbcf7aad9 [FastISel][ARM] Fix a bug in the integer materialization code.
getRegClassFor returns the incorrect register class when in Thumb2 mode.
This fix simply manually selects the register class as in the code just a few
lines above.

There is no test case for this code, because the code is currently
unreachable. This will be changed in a future commit and existing test
cases will exercise this code.

llvm-svn: 215583
2014-08-13 21:39:18 +00:00
Benjamin Kramer a7c40ef022 Canonicalize header guards into a common format.
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)

Changes made by clang-tidy with minor tweaks.

llvm-svn: 215558
2014-08-13 16:26:38 +00:00
Justin Bogner c0087f3611 IR: Print a newline when dumping Types
Type::dump() doesn't print a newline, which makes for a poor
experience in a debugger. This looks like it was an ommission
considering Value::dump() two lines above, so I've changed Type to add
a newline as well.

Of the two in-tree callers, one added a newline anyway, and I've
updated the other one to use Type::print instead.

llvm-svn: 215421
2014-08-12 03:24:59 +00:00
Quentin Colombet 55fd3ba33e [ARM] Mark VMOVDRR with the RegSequence property and implement the related
target hook.

This patch teaches the compiler that:
dX = VMOVDRR rY, rZ
is the same as:
dX = REG_SEQUENCE rY, ssub_0, rZ, ssub_1

<rdar://problem/12702965>

llvm-svn: 215404
2014-08-11 22:56:22 +00:00
Saleem Abdulrasool 27c78bf131 ARM: try harder to detect non-IT eligible instructions
For many Thumb-1 register register instructions, setting the CPSR is not
permitted inside an IT block.  We would not correctly flag those instructions.
The previous change to identify this scenario was insufficient as it did not
actually catch all the instances.  The current list is formed by manual
inspection of the ARMv6M ARM.

The change to the Thumb2 IT block test is due to the fact that the new more
stringent checking of the MIs results in the If Conversion pass being prevented
from executing (since not all the instructions in the BB are predicable).  This
results in code gen changes.

Thanks to Tim Northover for pointing out that the previous patch was
insufficient and hinting that the use of the v6M ARM would be much easier to use
than the v7 or v8!

llvm-svn: 215382
2014-08-11 20:13:25 +00:00
Oliver Stannard 11790b2dac ARM: __gnu_h2f_ieee and __gnu_f2h_ieee always use the soft-float calling convention
By default, LLVM uses the "C" calling convention for all runtime
library functions. The half-precision FP conversion functions use the
soft-float calling convention, and are needed for some targets which
use the hard-float convention by default, so must have their calling
convention explicitly set.

llvm-svn: 215348
2014-08-11 09:12:32 +00:00
Saleem Abdulrasool ed8885b402 ARM: correct isPredicable for MULS in ThHUMB mode
The ARM ARM states that CPSR may not be updated by a MUL in thumb mode.  Due to
an ordering of Thumb 2 Size Reduction and If Conversion, we would end up
generating a THUMB MULS inside an IT block.

The If Conversion pass uses the TTI isPredicable method to ensure that it can
transform a Basic Block.  However, because we only check for IT handling on
Thumb2 functions, we may miss some cases.  Even then, it only validates that the
CPSR is not *live* rather than it is not accessed.  This corrects the handling
for that particular case since the same restriction does not hold on the vast
majority of the instructions.

This does prevent the IfConversion optimization from kicking in in certain
cases, but generating correct code is more valuable.  Addresses PR20555.

llvm-svn: 215328
2014-08-10 22:20:37 +00:00
Joerg Sonnenberger 752b91bd82 If available, pass down the Fixup object to EvaluateAsRelocatable.
At least on PowerPC, the interpretation of certain modifiers depends on
the context they appear in.

llvm-svn: 215310
2014-08-10 11:35:12 +00:00
Eric Christopher b9fd9ed37e Temporarily Revert "Nuke the old JIT." as it's not quite ready to
be deleted. This will be reapplied as soon as possible and before
the 3.6 branch date at any rate.

Approved by Jim Grosbach, Lang Hames, Rafael Espindola.

This reverts commits r215111, 215115, 215116, 215117, 215136.

llvm-svn: 215154
2014-08-07 22:02:54 +00:00
Rafael Espindola f8b27c41e8 Nuke the old JIT.
I am sure we will be finding bits and pieces of dead code for years to
come, but this is a good start.

Thanks to Lang Hames for making MCJIT a good replacement!

llvm-svn: 215111
2014-08-07 14:21:18 +00:00
Pete Cooper c18261d467 Fix a whole bunch of binary literals which were the wrong size. All were being silently zero extended to the correct width.
The commit after this changes { } and 0bxx literals to be of type bits<n> and not int.  This means we need to write exactly the right number of bits, and not rely on the values being silently zero extended for us.

llvm-svn: 215082
2014-08-07 05:46:54 +00:00
Eric Christopher b5217507c7 Remove the target machine from CCState. Previously it was only used
to get the subtarget and that's accessible from the MachineFunction
now. This helps clear the way for smaller changes where we getting
a subtarget will require passing in a MachineFunction/Function as
well.

llvm-svn: 214988
2014-08-06 18:45:26 +00:00
Tim Northover 2a417b96d4 ARM: do not generate BLX instructions on Cortex-M CPUs.
Particularly on MachO, we were generating "blx _dest" instructions on M-class
CPUs, which don't actually exist. They happen to get fixed up by the linker
into valid "bl _dest" instructions (which is why such a massive issue has
remained largely undetected), but we shouldn't rely on that.

llvm-svn: 214959
2014-08-06 11:13:14 +00:00
Tim Northover d4d294dd51 ARM-MachO: materialize callee address correctly on v4t.
llvm-svn: 214958
2014-08-06 11:13:06 +00:00
Rafael Espindola b8141d55b9 Remove a virtual function from TargetMachine. NFC.
llvm-svn: 214929
2014-08-05 22:10:21 +00:00
Jonathan Roelofs ef84bda531 Re-apply r214881: Fix return sequence on armv4 thumb
This reverts r214893, re-applying r214881 with the test case relaxed a bit to
satiate the build bots.

POP on armv4t cannot be used to change thumb state (unilke later non-m-class
architectures), therefore we need a different return sequence that uses 'bx'
instead:

  POP {r3}
  ADD sp, #offset
  BX r3

This patch also fixes an issue where the return value in r3 would get clobbered
for functions that return 128 bits of data. In that case, we generate this
sequence instead:

  MOV ip, r3
  POP {r3}
  ADD sp, #offset
  MOV lr, r3
  MOV r3, ip
  BX lr

http://reviews.llvm.org/D4748

llvm-svn: 214928
2014-08-05 21:32:21 +00:00
Jonathan Roelofs 064eb5a177 Revert r214881 because it broke lots of build-bots
llvm-svn: 214893
2014-08-05 17:36:05 +00:00
Jonathan Roelofs f5fad3767b Fix return sequence on armv4 thumb
POP on armv4t cannot be used to change thumb state (unilke later non-m-class
architectures), therefore we need a different return sequence that uses 'bx'
instead:

  POP {r3}
  ADD sp, #offset
  BX r3

This patch also fixes an issue where the return value in r3 would get clobbered
for functions that return 128 bits of data. In that case, we generate this
sequence instead:

  MOV ip, r3
  POP {r3}
  ADD sp, #offset
  MOV lr, r3
  MOV r3, ip
  BX lr

http://reviews.llvm.org/D4748

llvm-svn: 214881
2014-08-05 17:13:17 +00:00
Keith Walker 1045717584 Specify that the thumb setend and blx <immed> instructions are not valid on an m-class target
llvm-svn: 214871
2014-08-05 15:11:59 +00:00
Keith Walker 292aa3d5f7 Define stc2/stc2l/ldc2/ldc2l as thumb2 instructions
llvm-svn: 214868
2014-08-05 14:58:05 +00:00
Eric Christopher fc6de428c8 Have MachineFunction cache a pointer to the subtarget to make lookups
shorter/easier and have the DAG use that to do the same lookup. This
can be used in the future for TargetMachine based caching lookups from
the MachineFunction easily.

Update the MIPS subtarget switching machinery to update this pointer
at the same time it runs.

llvm-svn: 214838
2014-08-05 02:39:49 +00:00
Renato Golin bc0b0378c5 Allow CP10/CP11 operations on ARMv5/v6
Those registers are VFP/NEON and vector instructions should be used instead,
but old cores rely on those co-processors to enable VFP unwinding. This change
was prompted by the libc++abi's unwinding routine and is also present in many
legacy low-level bare-metal code that we ought to compile/assemble.

Fixing bug PR20025 and allowing PR20529 to proceed with a fix in libc++abi.

llvm-svn: 214802
2014-08-04 23:21:56 +00:00
Eric Christopher d913448b38 Remove the TargetMachine forwards for TargetSubtargetInfo based
information and update all callers. No functional change.

llvm-svn: 214781
2014-08-04 21:25:23 +00:00
Akira Hatanaka dc08c30df9 [ARM] In dynamic-no-pic mode, ARM's post-RA pseudo expansion was incorrectly
expanding pseudo LOAD_STATCK_GUARD using instructions that are normally used
in pic mode. This patch fixes the bug.

<rdar://problem/17886592>

llvm-svn: 214614
2014-08-02 05:40:40 +00:00
Chandler Carruth 3707dda904 [SDAG] Let the DAG combiner take care of dead nodes rather than manually
deleting them. This already seems to work, as no tests fail without
this.

llvm-svn: 214601
2014-08-02 00:19:10 +00:00
Eric Christopher 6c05d9135f Add a non-const subtarget returning function to the target machine
so that we can use it to get the old-style JIT out of the subtarget.

This code should be removed when the old-style JIT is removed
(imminently).

llvm-svn: 214560
2014-08-01 21:18:01 +00:00
Juergen Ributzka 4c018a12a3 [FastISel][ARM] Do not emit stores for undef arguments.
This is a followup patch for r214366, which added the same behavior to the
AArch64 and X86 FastISel code. This fix reproduces the already existing
behavior of SelectionDAG in FastISel.

llvm-svn: 214531
2014-08-01 18:04:14 +00:00
James Molloy 137ce60ecf Allow only disassembling of M-class MSR masks that the assembler knows how to assemble back.
Note: The current code in DecodeMSRMask() rejects the unpredictable A/R MSR mask '0000' with Fail. The code in the patch follows this style and rejects unpredictable M-class MSR masks also with Fail (instead of SoftFail). If SoftFail is preferred in this case then additional changes to ARMInstPrinter (to print non-symbolic masks) and ARMAsmParser (to parse non-symbolic masks) will be needed.

Patch by Petr Pavlu!

llvm-svn: 214505
2014-08-01 12:42:11 +00:00
Tilmann Scheller 7cc0ed48f0 [ARM] Make the assembler reject unpredictable pre/post-indexed ARM LDRB/LDRSB instructions.
The ARM ARM prohibits LDRB/LDRSB instructions with writeback into the destination register. With this commit this constraint is now enforced and we stop assembling LDRH/LDRSH instructions with unpredictable behavior.

llvm-svn: 214500
2014-08-01 12:08:04 +00:00
Tilmann Scheller 8ff079c16b [ARM] Make the assembler reject unpredictable pre/post-indexed ARM LDRH/LDRSH instructions.
The ARM ARM prohibits LDRH/LDRSH instructions with writeback into the source register. With this commit this constraint is now enforced and we stop assembling LDRH/LDRSH instructions with unpredictable behavior.

llvm-svn: 214499
2014-08-01 11:33:47 +00:00
Tilmann Scheller 8ba74305da [ARM] Make the assembler reject unpredictable pre/post-indexed ARM LDR instructions.
The ARM ARM prohibits LDR instructions with writeback into the destination register. With this commit this constraint is now enforced and we stop assembling LDR instructions with unpredictable behavior.

llvm-svn: 214498
2014-08-01 11:08:51 +00:00
Louis Gerbarg 67474e3755 Make sure no loads resulting from load->switch DAGCombine are marked invariant
Currently when DAGCombine converts loads feeding a switch into a switch of
addresses feeding a load the new load inherits the isInvariant flag of the left
side. This is incorrect since invariant loads can be reordered in cases where it
is illegal to reoarder normal loads.

This patch adds an isInvariant parameter to getExtLoad() and updates all call
sites to pass in the data if they have it or false if they don't. It also
changes the DAGCombine to use that data to make the right decision when
creating the new load.

llvm-svn: 214449
2014-07-31 21:45:05 +00:00
Pete Cooper 95709e5604 Fix bit initializer which was one bit too long, but worked so long as we silently dropped the leading 0
llvm-svn: 214372
2014-07-31 01:43:51 +00:00
Tim Northover 4e13a61413 ARM: add __aeabi_d2h for truncation on AEABI systems
ARM does actually define the name for this conversion, so we should use it on
"-eabi" platforms.

llvm-svn: 214176
2014-07-29 09:56:45 +00:00
Saleem Abdulrasool 8988c2a524 ARM: correct handling of features in arch_extension
The subtarget information is the ultimate source of truth for the feature set
that is enabled at this point.  We would previously not propagate the feature
information to the subtarget.  While this worked for the most part (features
would be enabled/disabled as requested), if another operation that changed the
feature bits was encountered (such as a mode switch via a .arm or .thumb
directive), we would end up resetting the behaviour of the architectural
extensions.

Handling this properly requires a slightly more complicated handling.  We need
to check if the feature is now being toggled.  If so, only then do we toggle the
features.  In return, we no longer have to calculate the feature bits ourselves.

The test changes are mostly to the diagnosis, which is now more uniform (a nice
side effect!).  Add an additional test to ensure that we handle this case
properly.

Thanks to Nico Weber for alerting me to this issue!

llvm-svn: 214057
2014-07-27 19:07:09 +00:00
Saleem Abdulrasool 45cf67b8e9 ARM: convert loop to range based
Convert a loop to use range based iteration.  Rename structure members to help
naming, and make structure definition anonymous.  NFC.

llvm-svn: 214056
2014-07-27 19:07:05 +00:00
Matt Arsenault 6f2a526101 Add alignment value to allowsUnalignedMemoryAccess
Rename to allowsMisalignedMemoryAccess.

On R600, 8 and 16 byte accesses are mostly OK with 4-byte alignment,
and don't need to be split into multiple accesses. Vector loads with
an alignment of the element type are not uncommon in OpenCL code.

llvm-svn: 214055
2014-07-27 17:46:40 +00:00
Nico Weber a822d94f57 Wrap to 80 columns, no behavior change.
llvm-svn: 213975
2014-07-25 21:37:41 +00:00
Akira Hatanaka e5b6e0d231 [stack protector] Fix a potential security bug in stack protector where the
address of the stack guard was being spilled to the stack.

Previously the address of the stack guard would get spilled to the stack if it
was impossible to keep it in a register. This patch introduces a new target
independent node and pseudo instruction which gets expanded post-RA to a
sequence of instructions that load the stack guard value. Register allocator
can now just remat the value when it can't keep it in a register. 

<rdar://problem/12475629>

llvm-svn: 213967
2014-07-25 19:31:34 +00:00
Amara Emerson 115d2df8a4 [ARM] Emit ABI_PCS_R9_use build attribute.
Patch by Ben Foster!

Differential Revision: http://reviews.llvm.org/D4657

llvm-svn: 213944
2014-07-25 14:03:14 +00:00
Akira Hatanaka 16e47ff42e [ARM] In thumb mode, emit directive ".code 16" before file level inline
assembly instructions.

This is necessary to ensure ARM assembler switches to Thumb mode before it
starts assembling the file level inline assembly instructions at the beginning
of a .s file.

<rdar://problem/17757232>

llvm-svn: 213924
2014-07-25 05:12:49 +00:00
Hal Finkel cc39b67530 AA metadata refactoring (introduce AAMDNodes)
In order to enable the preservation of noalias function parameter information
after inlining, and the representation of block-level __restrict__ pointer
information (etc.), additional kinds of aliasing metadata will be introduced.
This metadata needs to be carried around in AliasAnalysis::Location objects
(and MMOs at the SDAG level), and so we need to generalize the current scheme
(which is hard-coded to just one TBAA MDNode*).

This commit introduces only the necessary refactoring to allow for the
introduction of other aliasing metadata types, but does not actually introduce
any (that will come in a follow-up commit). What it does introduce is a new
AAMDNodes structure to hold all of the aliasing metadata nodes associated with
a particular memory-accessing instruction, and uses that structure instead of
the raw MDNode* in AliasAnalysis::Location, etc.

No functionality change intended.

llvm-svn: 213859
2014-07-24 12:16:19 +00:00
NAKAMURA Takumi 98d18be5fe Prune dependency to MC from each target disassembler.
llvm-svn: 213856
2014-07-24 11:45:11 +00:00
Tilmann Scheller 96ef72e54a [ARM] Make the assembler reject unpredictable pre/post-indexed ARM STRH instructions.
The ARM ARM prohibits STRH instructions with writeback into the source register. With this commit this constraint is now enforced and we stop assembling STRH instructions with unpredictable behavior.

llvm-svn: 213850
2014-07-24 09:55:46 +00:00
NAKAMURA Takumi 9c3bd7618a Update library dependencies.
llvm-svn: 213832
2014-07-24 02:10:42 +00:00
Rafael Espindola 45bcf8a59c Fix the build when building with only the ARM backend.
llvm-svn: 213814
2014-07-23 22:54:28 +00:00
Tim Northover 14ff2df05c ARM: spot SBFX-compatbile code expressed with sign_extend_inreg
We were assuming all SBFX-like operations would have the shl/asr form, but
often when the field being extracted is an i8 or i16, we end up with a
SIGN_EXTEND_INREG acting on a shift instead. Simple enough to check for though.

llvm-svn: 213754
2014-07-23 13:59:12 +00:00
Tim Northover 7ad2a0e0c2 ARM: add patterns for [su]xta[bh] from just a shift.
Although the final shifter operand is a rotate, this actually only matters for
the half-word extends when the amount == 24. Otherwise folding a shift in is
just as good.

llvm-svn: 213753
2014-07-23 13:59:07 +00:00
Tilmann Scheller 2727279117 [ARM] Make the assembler reject unpredictable pre/post-indexed ARM STRB instructions.
The ARM ARM prohibits STRB instructions with writeback into the source register. With this commit this constraint is now enforced and we stop assembling STRB instructions with unpredictable behavior.

llvm-svn: 213750
2014-07-23 13:03:47 +00:00
Tilmann Scheller 3352a58ddc [ARM] Make the assembler reject unpredictable pre/post-indexed ARM STR instructions.
The ARM ARM prohibits STR instructions with writeback into the source register. With this commit this constraint is now enforced and we stop assembling STR instructions with unpredictable behavior.

llvm-svn: 213745
2014-07-23 12:38:17 +00:00
Tilmann Scheller c28f0d587d [ARM] Add earlyclobber constraint to pre/post-indexed ARM STRH instructions.
The post-indexed instructions were missing the constraint, causing unpredictable STRH instructions to be emitted.

The earlyclobber constraint on the pre-indexed STR instructions is not strictly necessary, as the instruction selection for pre-indexed STR instructions goes through an additional layer of pseudo instructions which have the constraint defined, however it doesn't hurt to specify the constraint directly on the pre-indexed instructions as well, since at some point someone might create instances of them programmatically and then the constraint is definitely needed.

llvm-svn: 213729
2014-07-23 08:12:51 +00:00
Ulrich Weigand 46797c6960 [MC] Pass MCSymbolData to needsRelocateWithSymbol
As discussed in a previous checking to support the .localentry
directive on PowerPC, we need to inspect the actual target symbol
in needsRelocateWithSymbol to make the appropriate decision based
on that symbol's st_other bits.

Currently, needsRelocateWithSymbol does not get the target symbol.
However, it is directly available to its sole caller.  This patch
therefore simply extends the needsRelocateWithSymbol by a new
parameter "const MCSymbolData &SD", passes in the target symbol,
and updates all derived implementations.

In particular, in the PowerPC implementation, this patch removes
the FIXME added by the previous checkin.

llvm-svn: 213487
2014-07-20 23:15:06 +00:00
Saleem Abdulrasool c4e00289a7 ARM: correct WoA __builtin_alloca handling on O0
When performing a dynamic stack adjustment without optimisations, we would mark
SP as def and R4 as kill.  This occurred as part of the expansion of a
WIN__CHKSTK SDNode which indicated the proper handling of SP and R4.  The result
would be that we would double define SP as part of an operation, which is
obviously incorrect.

Furthermore, the VTList for the chain had an incorrect parameter type of i32
instead of Other.

Correct these to permit proper lowering of __builtin_alloca at -O0.

llvm-svn: 213442
2014-07-19 01:29:51 +00:00
David Peixotto ae5ba76221 MC: support different sized constants in constant pools
On AArch64 the pseudo instruction ldr <reg>, =... supports both
32-bit and 64-bit constants. Add support for 64 bit constants for
the pools to support the pseudo instruction fully.

Changes the AArch64 ldr-pseudo tests to use 32-bit registers and
adds tests with 64-bit registers.

Patch by Janne Grunau!

Differential Revision: http://reviews.llvm.org/D4279

llvm-svn: 213387
2014-07-18 16:05:14 +00:00
Tim Northover 4e80b584fe ARM: support legalisation of "fptrunc ... to half" operations.
llvm-svn: 213373
2014-07-18 13:01:19 +00:00
Renato Golin e48d9dc15e Suppress 'not handled in switch' warning
llvm-svn: 213371
2014-07-18 12:13:04 +00:00
Tilmann Scheller 0fc933d6b8 [ARM] Add earlyclobber constraint to pre/post-indexed ARM STR instructions.
The post-indexed instructions were missing the constraint, causing unpredictable STR instructions to be emitted.

The earlyclobber constraint on the pre-indexed STR instructions is not strictly necessary, as the instruction selection for pre-indexed STR instructions goes through an additional layer of pseudo instructions which have the constraint defined, however it doesn't hurt to specify the constraint directly on the pre-indexed instructions as well, since at some point someone might create instances of them programmatically and then the constraint is definitely needed.

This fixes PR20323.

llvm-svn: 213369
2014-07-18 12:05:49 +00:00
Renato Golin c17a07b36a Refactor ARM subarchitecture parsing
Re-commit of a patch to rework the triple parsing on ARM to a more sane
model.

Patch by Gabor Ballabas.

llvm-svn: 213367
2014-07-18 12:00:48 +00:00
Tim Northover 53f3bcf0e9 ARM: support direct f16 <-> f64 conversions
ARMv8 has instructions to handle it, otherwise a libcall is needed.

llvm-svn: 213254
2014-07-17 11:27:04 +00:00
Tim Northover fd7e424935 CodeGen: extend f16 conversions to permit types > float.
This makes the two intrinsics @llvm.convert.from.f16 and
@llvm.convert.to.f16 accept types other than simple "float". This is
only strictly needed for the truncate operation, since otherwise
double rounding occurs and there's no way to represent the strict IEEE
conversion. However, for symmetry we allow larger types in the extend
too.

During legalization, we can expand an "fp16_to_double" operation into
two extends for convenience, but abort when the truncate isn't legal. A new
libcall is probably needed here.

Even after this commit, various target tweaks are needed to actually use the
extended intrinsics. I've put these into separate commits for clarity, so there
are no actual tests of f64 conversion here.

llvm-svn: 213248
2014-07-17 10:51:23 +00:00
Chris Bieneman df4b763be5 [RegisterCoalescer] Moving the RegisterCoalescer subtarget hook onto the TargetRegisterInfo instead of the TargetSubtargetInfo.
llvm-svn: 213188
2014-07-16 20:13:31 +00:00
Chris Bieneman 80a866a316 Added documentation for SizeMultiplier in the ARM subtarget hook for register coalescing. Also fixed some 80 col violations.
No functional code changes.

llvm-svn: 213169
2014-07-16 16:27:31 +00:00
Sanjay Patel a2f658d69d Move Post RA Scheduling flag bit into SchedMachineModel
Refactoring; no functional changes intended

    Removed PostRAScheduler bits from subtargets (X86, ARM).
    Added PostRAScheduler bit to MCSchedModel class.
    This bit is set by a CPU's scheduling model (if it exists).
    Removed enablePostRAScheduler() function from TargetSubtargetInfo and subclasses.
    Fixed the existing enablePostMachineScheduler() method to use the MCSchedModel (was just returning false!).
    Added methods to TargetSubtargetInfo to allow overrides for AntiDepBreakMode, CriticalPathRCs, and OptLevel for PostRAScheduling.
    Added enablePostRAScheduler() function to PostRAScheduler class which queries the subtarget for the above values.
    Preserved existing scheduler behavior for ARM, MIPS, PPC, and X86: 
       a. ARM overrides the CPU's postRA settings by enabling postRA for any non-Thumb or Thumb2 subtarget. 
       b. MIPS overrides the CPU's postRA settings by enabling postRA for everything. 
       c. PPC overrides the CPU's postRA settings by enabling postRA for everything. 
       d. X86 is the only target that actually has postRA specified via sched model info.

Differential Revision: http://reviews.llvm.org/D4217

llvm-svn: 213101
2014-07-15 22:39:58 +00:00
Chris Bieneman 03695ab57e [RegisterCoalescer] Add new subtarget hook allowing targets to opt-out of coalescing.
The coalescer is very aggressive at propagating constraints on the register classes, and the register allocator doesn’t know how to split sub-registers later to recover. This patch provides an escape valve for targets that encounter this problem to limit coalescing.

This patch also implements such for ARM to lower register pressure when using lots of large register classes. This works around PR18825.

llvm-svn: 213078
2014-07-15 17:18:41 +00:00
Renato Golin b8a86c43c0 Revert "Refactor ARM subarchitecture parsing"
This reverts commit 7b4a6882467e7fef4516a0cbc418cbfce0fc6f6d.

llvm-svn: 212521
2014-07-08 10:06:16 +00:00
Renato Golin 1e9c282cd1 Refactor ARM subarchitecture parsing
According to a FIXME in ARMMCTargetDesc.cpp the ARM version parsing should be
in the Triple helper class.

Patch by: Gabor Ballabas

llvm-svn: 212479
2014-07-07 20:01:11 +00:00
Saleem Abdulrasool 763f9a50a5 ARM: properly lower dllimport'ed global values
This completes the handling for DLL import storage symbols when lowering
instructions.  A DLL import storage symbol must have an additional load
performed prior to use.  This is applicable to variables and functions.

This is particularly important for non-function symbols as it is possible to
handle function references by emitting a thunk which performs the translation
from the unprefixed __imp_ symbol to the proper symbol (although, this is a
non-optimal lowering).  For a variable symbol, no such thunk can be
accommodated.

llvm-svn: 212431
2014-07-07 05:18:35 +00:00
Saleem Abdulrasool 220a044888 ARM: correctly mangle dllimport symbols
Add support for tracking DLLImport storage class information on a per symbol
basis in the ARM instruction selection.  Use that information to correctly
mangle the symbol (dllimport symbols are referenced via *__imp_<name>).

llvm-svn: 212430
2014-07-07 05:18:30 +00:00
Saleem Abdulrasool 1eb4a28b44 ARM: unify symbol name retrieval
Ensure that all paths that retrieve the symbol name go through GetARMGVSymbol
rather than getSymbol.  This is desirable so that any global symbol mangling can
be centralised to this function.  The motivation for this is handling of symbols
that are marked as having dll import dll storage.  Such a symbol requires an
extra load that is currently handled in the backend and a __imp_ prefix on the
symbol name.

llvm-svn: 212429
2014-07-07 05:18:22 +00:00
Tim Northover 1bc367a41b ARM: when falling back to scattered relocs, keep the type.
The linker relies on relocation type info (e.g. is it a branch?) to perform the
correct actions, so we should keep that even when we end up using a scattered
relocation for whatever reason.

rdar://problem/17553104

llvm-svn: 212333
2014-07-04 10:58:05 +00:00
Eric Christopher c1058df66f Move function dependent resetting of a subtarget variable out of the
subtarget. This involved having the movt predicate take the current
function - since we care about size in instruction selection for
whether or not to use movw/movt take the function so we can check
the attributes. This required adding the current MachineFunction to
FastISel and propagating through.

llvm-svn: 212309
2014-07-04 01:55:26 +00:00
Eric Christopher 2f991c9ee1 Remove caching of the target machine and initialization of the
subtarget from ARMISelDAGtoDAG. The former is unnecessary and the
latter is initialized on each runOnMachineFunction.

llvm-svn: 212297
2014-07-03 22:24:49 +00:00
Yi Kong 93e52da641 [ARM] Implement ISB memory barrier intrinsic
Adds support for __builtin_arm_isb. Also corrects DSB and ISB instructions
modelling by adding has-side-effects property.

llvm-svn: 212276
2014-07-03 16:00:41 +00:00
Juergen Ributzka 3bd03c7099 [DAG] Pass the argument list to the CallLoweringInfo via move semantics. NFCI.
The argument list vector is never used after it has been passed to the
CallLoweringInfo and moving it to the CallLoweringInfo is cleaner and
pretty much as cheap as keeping a pointer to it.

llvm-svn: 212135
2014-07-01 22:01:54 +00:00
Scott Douglass 7650a9b871 ARM: take care not to set the ThumbFunc bit on TLS data symbols
This fixes LNT SingleSource/UnitTests/Threads with -mthumb.

Differential Revision: http://reviews.llvm.org/D4324

llvm-svn: 212029
2014-06-30 09:37:24 +00:00
Saleem Abdulrasool 4a1e409a4d ARM: use symbolic name for constant
This just changes the constant value to the symbolic name corresponding to it.
NFC.

llvm-svn: 212011
2014-06-30 03:11:14 +00:00
Eric Christopher 83e0723457 Remove extraneous includes from the target machines.
llvm-svn: 211800
2014-06-26 19:30:05 +00:00
Eric Christopher 80b24ef429 Move all of the ARM subtarget features down onto the subtarget
rather than the target machine.

llvm-svn: 211799
2014-06-26 19:30:02 +00:00
Eric Christopher 45fb7b6397 Move the frame lowering constructors out of line to avoid circular
includes.

llvm-svn: 211798
2014-06-26 19:29:59 +00:00
Renato Golin ac561c3ac7 Added parsing co-processor names starting with "cr"
Additional compliant GAS names for coprocessor register name
are enabled for all instruction with parameter MCK_CoprocReg:
LDC,LDC2,STC,STC2,CDP,CDP2,MCR,MCR2,MCRR,MCRR2,MRC,MRC2,MRRC,MRRC2

Patch by Andrey Kuharev.

llvm-svn: 211776
2014-06-26 13:10:53 +00:00
Rafael Espindola e2c6624475 Move expression visitation logic up to MCStreamer.
Remove the duplicate from MCRecordStreamer. No functionality change.

llvm-svn: 211714
2014-06-25 15:45:33 +00:00
Rafael Espindola 2be1281d43 Simplify the visitation of target expressions. No functionality change.
llvm-svn: 211707
2014-06-25 15:29:54 +00:00
Christian Pirker c6308f59b2 ARM: Fix TPsoft for Thumb mode
Reviewed at http://reviews.llvm.org/D4230

llvm-svn: 211601
2014-06-24 15:45:59 +00:00
Christian Pirker 6f81e75dab ARMEB: Vector extend operations
Reviewed at http://reviews.llvm.org/D4043

llvm-svn: 211520
2014-06-23 18:05:53 +00:00
Tim Northover 2099862a50 ARM: mark UBFX as not allowing PC.
Strictly, it's unpredictable. But we don't quite model that yet and an error is
better than ignoring the issue. This one somehow got left out before though.

rdar://problem/15997748

llvm-svn: 211490
2014-06-23 09:20:02 +00:00
Rafael Espindola 1fc003e6c5 Allow a target to create a null streamer.
Targets can assume that a target streamer is present, so they have to be able
to construct a null streamer in order to set the target streamer in it to.

Fixes a crash when using the null streamer with arm.

llvm-svn: 211358
2014-06-20 13:11:28 +00:00
Oliver Stannard 5dc2934ba2 Emit the ARM build attributes ABI_PCS_wchar_t and ABI_enum_size.
Emit the ARM build attributes ABI_PCS_wchar_t and ABI_enum_size based on
module flags metadata.

llvm-svn: 211349
2014-06-20 10:08:11 +00:00
Karthik Bhat e03a25da70 Add Support to Recognize and Vectorize NON SIMD instructions in SLPVectorizer.
This patch adds support to recognize patterns such as fadd,fsub,fadd,fsub.../add,sub,add,sub... and
vectorizes them as vector shuffles if they are profitable.
These patterns of vector shuffle can later be converted to instructions such as addsubpd etc on X86.
Thanks to Arnold and Hal for the reviews. http://reviews.llvm.org/D4015 

llvm-svn: 211339
2014-06-20 04:32:48 +00:00
Eric Christopher c40e5edbbc Add a new subtarget hook for whether or not we'd like to enable
the atomic load linked expander pass to run for a particular
subtarget. This requires a check of the subtarget and so save
the TargetMachine rather than only TargetLoweringInfo and update
all callers.

llvm-svn: 211314
2014-06-19 21:03:04 +00:00
Alp Toker 1d099d9339 Fix typos
llvm-svn: 211304
2014-06-19 19:41:26 +00:00
Craig Topper 35b2f75733 Convert some assert(0) to llvm_unreachable or fold an 'if' condition into the assert.
llvm-svn: 211254
2014-06-19 06:10:58 +00:00
Eric Christopher 3d19f1388f Move ARMJITInfo off of the TargetMachine and down onto the subtarget.
This required untangling a mess of headers that included around.

This a recommit of r210953 with a fix for the removed accessor
for JITInfo.

llvm-svn: 211233
2014-06-18 22:48:09 +00:00
Weiming Zhao 8c89973462 [ARM] [MC] Refactor the constant pool classes
ARMTargetStreamer implements ConstantPool and AssmeblerConstantPools
to keep track of assembler-generated constant pools that are used for
ldr-pseudo.

When implementing ldr-pseudo for AArch64, these two classes can be reused.
So this patch factors them out from ARM target to the general MC lib.

llvm-svn: 211198
2014-06-18 18:17:25 +00:00
Craig Topper 2a30d7889f Replace some assert(0)'s with llvm_unreachable.
llvm-svn: 211141
2014-06-18 05:05:13 +00:00
James Molloy c1fd09ba2c Fix memory leak of RegScavenger accidentally added in r211037.
llvm-svn: 211097
2014-06-17 12:31:41 +00:00
Jim Grosbach 07393ba31b ARM: intrinsic support for rbit.
We already have an ARMISD node. Create an intrinsic to map to it so we can
add support for the frontend __rbit() intrinsic.

rdar://9283021

llvm-svn: 211057
2014-06-16 21:55:30 +00:00
Eric Christopher daca3cc54a Since the DataLayout is always found off of the subtarget go ahead
and query the base target machine implementation for it.

llvm-svn: 211055
2014-06-16 21:18:27 +00:00
Tim Northover b45c3b74b4 ARM: implement correct atomic operations on v7M
ARM v7M has ldrex/strex but not ldrexd/strexd. This means 32-bit
operations should work as normal, but 64-bit ones are almost certainly
doomed.

Patch by Phoebe Buckheister.

llvm-svn: 211042
2014-06-16 18:49:36 +00:00
James Molloy f6419cfb14 Refactor the disabling of Thumb-1 LDM/STM generation
Originally I switched the LD/ST optimizer off in TargetMachine as it was previously, but Eric has suggested he'd prefer that it be short-circuited in the pass itself.

No functionality change.

llvm-svn: 211037
2014-06-16 16:42:53 +00:00
Christian Pirker 2cc1cf0d4b ARMEB: Fix trunc store for vector types
Reviewed at http://reviews.llvm.org/D4135

llvm-svn: 211010
2014-06-16 09:17:30 +00:00
Eric Christopher f6db93ab81 Temporarily revert r210953 in an attempt to bring the ARM buildbots
back.

llvm-svn: 210996
2014-06-15 19:55:14 +00:00
Eric Christopher fb0c26c696 Remove InstrItineraryData off of the TargetMachine - it's already
on the subtarget and just forward the accessor.

llvm-svn: 210955
2014-06-13 23:11:13 +00:00
Eric Christopher a0cdc005dd Move ARMJITInfo off of the TargetMachine and down onto the subtarget.
This required untangling a mess of headers that included around.

llvm-svn: 210953
2014-06-13 23:04:46 +00:00
Eric Christopher f047bfd115 The hazard recognizer only needs a subtarget, not a target machine
so make it take one. Fix up all users accordingly.

llvm-svn: 210948
2014-06-13 22:38:52 +00:00
Oliver Stannard b5e596f7c3 ARM: Fix fastcc calling convention for Thumb1
When targetting Thumb1 on a processor which has a VFP unit (which
is not accessible from Thumb1), we were converting the fastcc calling
convention to AAPCS-VFP, which is not possible.

llvm-svn: 210889
2014-06-13 08:33:03 +00:00
Eric Christopher 030294e4c5 Move ARMSelectionDAGInfo from the TargetMachine to the subtarget.
llvm-svn: 210862
2014-06-13 00:20:39 +00:00
Eric Christopher a47f6804d2 Move to a private function to initialize subtarget dependencies
so we can use initializer lists for the ARMSubtarget and then
use this to initialize a moved DataLayout on the subtarget from
the TargetMachine.

llvm-svn: 210861
2014-06-13 00:20:35 +00:00
Eric Christopher 70e005a171 Have ARMSelectionDAGInfo take a DataLayout as it's argument as the
DAG has access to the subtarget and TargetSelectionDAGInfo only
needs a DataLayout.

llvm-svn: 210859
2014-06-12 23:39:49 +00:00
Saleem Abdulrasool 65ca57a418 CodeGen: enable mov.w/mov.t pairs with minsize for WoA
Windows on ARM uses COFF/PE which is intrinsically position independent.  For
the case of 32-bit immediates, use a pair-wise relocation as otherwise we may
exceed the range of operators.  This fixes a code generation crash when using
-Oz when targeting Windows on ARM.

llvm-svn: 210814
2014-06-12 20:06:33 +00:00
James Molloy 1417b0be3e Disable the load/store optimization pass for Thumb-1.
Moritz's changes have improved codegen a lot, but further testing showed significant correctness problems. Disable by default until these have been worked out.

Patch by Moritz Roth!

llvm-svn: 210789
2014-06-12 15:18:33 +00:00
Jim Grosbach 7a930bf9ef ARM: honor hex immediate formatting for ldr/str i12 offsets.
Previously we would always print the offset as decimal, regardless of
the formatting requested. Now we use the formatImm() helper so the value
is printed as the client (LLDB in the motivating example) requested.

Before:
ldr.w r8, [sp, #180] @ always

After:
ldr.w r8, [sp, #0xb4] @ when printing hex immediates
ldr.w r8, [sp, #0180] @ when printing decimal immediates

rdar://17237103

llvm-svn: 210701
2014-06-11 20:26:45 +00:00
Renato Golin 65eea557ae Fix a bug in the Thumb1 ARM Load/Store optimizer
Previously, the basic block was searched for future uses of the base register,
and if necessary any writeback to the base register was reset using a SUB
instruction (e.g. before calling a function) just before such a use. However,
this step happened *before* the merged LDM/STM instruction was built. So if
there was (e.g.) a function call directly after the not-yet-formed LDM/STM,
the pass would first insert a SUB instruction to reset the base register,
and then (at the same location, incorrectly) insert the LDM/STM itself.

This patch fixes PR19972. Patch by Moritz Roth.

llvm-svn: 210542
2014-06-10 16:39:21 +00:00
Saleem Abdulrasool abac6e92a0 ARM: add VLA extension for WoA Itanium ABI
The armv7-windows-itanium environment is nearly identical to the MSVC ABI. It
has a few divergences, mostly revolving around the use of the Itanium ABI for
C++. VLA support is one of the extensions that are amongst the set of the
extensions.

This adds support for proper VLA emission for this environment. This is
somewhat similar to the handling for __chkstk emission on X86 and the large
stack frame emission for ARM. The invocation style for chkstk is still
controlled via the -mcmodel flag to clang.

Make an explicit note that this is an extension.

llvm-svn: 210489
2014-06-09 20:18:42 +00:00
David Blaikie 960ea3f018 AsmMatchers: Use unique_ptr to manage ownership of MCParsedAsmOperand
I saw at least a memory leak or two from inspection (on probably
untested error paths) and r206991, which was the original inspiration
for this change.

I ran this idea by Jim Grosbach a few weeks ago & he was OK with it.
Since it's a basically mechanical patch that seemed sufficient - usual
post-commit review, revert, etc, as needed.

llvm-svn: 210427
2014-06-08 16:18:35 +00:00
Saleem Abdulrasool 90386ad60a ARM: correct assertion for long-calls on WoA
COFF/PE, so the relocation model is never static.  Loosen the assertion
accordingly.  The relocation can still be emitted properly, as it will be
converted to an IMAGE_REL_ARM_ADDR32 which will be resolved by the loader
taking the base relocation into account.  This is necessary to permit the
emission of long calls which can be controlled via the -mlong-calls option in
the driver.

llvm-svn: 210399
2014-06-07 20:29:27 +00:00
Eric Christopher 0dd8d486b3 Have TargetSelectionDAGInfo take a DataLayout initializer rather than
a TargetMachine since the only thing it wants is DataLayout.

llvm-svn: 210366
2014-06-06 19:04:48 +00:00
Tom Roeder 44cb65fff1 Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute.
It includes a pass that rewrites all indirect calls to jumptable functions to pass through these tables.

This also adds backend support for generating the jump-instruction tables on ARM and X86.
Note that since the jumptable attribute creates a second function pointer for a
function, any function marked with jumptable must also be marked with unnamed_addr.

llvm-svn: 210280
2014-06-05 19:29:43 +00:00
Andrew Trick 8d2ee37f31 Add a subtarget hook: enablePostMachineScheduler.
As requested by AArch64 subtargets.

Note that this will have no effect until the
AArch64 target actually enables the pass like this:
substitutePass(&PostRASchedulerID, &PostMachineSchedulerID);

As soon as armv7 switches over, PostMachineScheduler will become the
default postRA scheduler, so this won't be necessary any more.
Targets using the old postRA schedule would then do:
substitutePass(&PostMachineSchedulerID, &PostRASchedulerID);

llvm-svn: 210167
2014-06-04 07:06:27 +00:00
Christian Pirker 762b2c624f ARMEB: Fix function return type f64
Reviewed at http://reviews.llvm.org/D3968

llvm-svn: 209990
2014-06-01 09:30:52 +00:00
Alp Toker 5f83e477c3 Update a couple of header inclusion guards
llvm-svn: 209980
2014-05-31 21:26:09 +00:00
Eric Christopher 8995833a34 Have the TLOF creation take a Triple rather than needing a subtarget.
llvm-svn: 209937
2014-05-31 00:07:32 +00:00
Tim Northover 86f60b7266 ARM: use AAPCS-style prologues for embedded MachO.
Darwin prologues save their GPRs in two stages: a narrow push of r0-r7 & lr,
followed by a wide push of the remaining registers if there are any. AAPCS uses
a single push.w instruction.

It turns out that, on average, enough registers get pushed that code is smaller
in the AAPCS prologue, which is a nice property for M-class programmers. They
also have other options available for back-traces, so can hopefully deal with
the fact that FP & LR aren't adjacent in memory.

rdar://problem/15909583

llvm-svn: 209895
2014-05-30 13:23:06 +00:00
Tim Northover b4ddc0845a ARM & AArch64: make use of common cmpxchg idioms after expansion
The C and C++ semantics for compare_exchange require it to return a bool
indicating success. This gets mapped to LLVM IR which follows each cmpxchg with
an icmp of the value loaded against the desired value.

When lowered to ldxr/stxr loops, this extra comparison is redundant: its
results are implicit in the control-flow of the function.

This commit makes two changes: it replaces that icmp with appropriate PHI
nodes, and then makes sure earlyCSE is called after expansion to actually make
use of the opportunities revealed.

I've also added -{arm,aarch64}-enable-atomic-tidy options, so that
existing fragile tests aren't perturbed too much by the change. Many
of them either rely on undef/unreachable too pervasively to be
restored to something well-defined (particularly while making sure
they test the same obscure assert from many years ago), or depend on a
particular CFG shape, which is disrupted by SimplifyCFG.

rdar://problem/16227836

llvm-svn: 209883
2014-05-30 10:09:59 +00:00
Amara Emerson ceeb1c4830 [ARM] Emit correct build attributes for the relocation models.
Patch by Asiri Rathnayake.

llvm-svn: 209656
2014-05-27 13:30:21 +00:00