Commit Graph

10312 Commits

Author SHA1 Message Date
David Green 22a2209433 [ARM] Reserve an emergency spill slot for fp16 addressing modes that need it
Similar to D67327, but this time for the FP16 VLDR and VSTR instructions that
use the AddrMode5FP16 addressing mode. We need to reserve an emergency spill
slot for instructions that will be out of range to use sp directly.
AddrMode5FP16 is 8 bits with a scale of 2.

Differential Revision: https://reviews.llvm.org/D67483

llvm-svn: 372132
2019-09-17 15:23:09 +00:00
Sam Parker 1d9ba08543 [ARM] Fix for buildbots
Remove setPreservesCFG from ARMConstantIslandPass and add a couple
of -verify-machine-dom-info instances into the existing codegen
tests.

llvm-svn: 372126
2019-09-17 14:21:36 +00:00
David Green 1ff9553057 [ARM] Fix for MVE load/store stack accesses
MVE loads and stores have a 7 bit immediate range, scaled by the length of the type. This needs to be taught to the stack estimation code to ensure that an emergency spill slot is reserved in case we run out of registers when materialising stack indices.

Also the narrowing loads/stores can be created with frame indices even though they do not accept SP as a register. We need in those cases to make sure we have an emergency register to use as the frame base, as SP can never be used.

Differential Revision: https://reviews.llvm.org/D67327

llvm-svn: 372114
2019-09-17 12:58:51 +00:00
Benjamin Kramer df4b9a3f4f Hide implementation details in namespaces.
llvm-svn: 372113
2019-09-17 12:56:29 +00:00
Sam Parker 36c922278e [ARM][LowOverheadLoops] Add LR def safety check
Converting the *LoopStart pseudo instructions into DLS/WLS results in
LR being defined. These instructions were inserted on the assumption
that LR would already contain the loop counter because a mov is
introduced during ISel as the the consumers in the loop can only use
LR. That assumption proved wrong!

So perform a safety check, finding an appropriate place to insert the
DLS/WLS instructions or revert if this isn't possible.

Differential Revision: https://reviews.llvm.org/D67539

llvm-svn: 372111
2019-09-17 12:19:32 +00:00
Graham Hunter 1a9195d817 [SVE][MVT] Fixed-length vector MVT ranges
* Reordered MVT simple types to group scalable vector types
    together.
  * New range functions in MachineValueType.h to only iterate over
    the fixed-length int/fp vector types.
  * Stopped backends which don't support scalable vector types from
    iterating over scalable types.

Reviewers: sdesmalen, greened

Reviewed By: greened

Differential Revision: https://reviews.llvm.org/D66339

llvm-svn: 372099
2019-09-17 10:19:23 +00:00
Sam Parker 95b28a4c72 [ARM] LE support in ConstantIslands
The low-overhead branch extension provides a loop-end 'LE' instruction
that performs no decrement nor compare, it just jumps backwards. This
patch modifies the constant islands pass to try to insert LE
instructions in place of a Thumb2 conditional branch, instead of
shrinking it. This only happens if a cmp can be converted to a cbn/z
and used to exit the loop.

Differential Revision: https://reviews.llvm.org/D67404

llvm-svn: 372085
2019-09-17 09:08:05 +00:00
Sam Parker 26a475afe5 [ARM][MVE] Add invalidForTailPredication to TSFlags
Set this bit for the MVE reduction instructions to prevent a loop from
becoming tail predicated in their presence.

Differential Revision: https://reviews.llvm.org/D67444

llvm-svn: 372076
2019-09-17 07:43:04 +00:00
David Green 8d21460dc5 [ARM] A predicate cast of a predicate cast is a predicate cast
The adds some very basic folding of PREDICATE_CASTS, removing cases when they
are chained together. These would already be removed eventually, as these are
lowered to copies. This just allows it to happen earlier, which can help other
simplifications.

Differential Revision: https://reviews.llvm.org/D67591

llvm-svn: 372012
2019-09-16 17:29:07 +00:00
Oliver Cruickshank ee6fbebbaf [ARM] Add patterns for BSWAP intrinsic on MVE
BSWAP can use the VREV instruction on MVE to produce better results than
expanding.

llvm-svn: 372002
2019-09-16 15:20:10 +00:00
Oliver Cruickshank e9510a6cad [ARM] Add patterns for bitreverse intrinsic on MVE
BITREVERSE can use the VBRSR which will reverse and right shift.
Shifting right by 0 will just reverse the bits.

llvm-svn: 372001
2019-09-16 15:20:03 +00:00
Oliver Cruickshank 5f799ef162 [ARM] Lower CTTZ on MVE
Lower CTTZ on MVE using VBRSR and VCLS which will reverse the bits and
count the leading zeros, equivalent to a count trailing zeros (CTTZ).

llvm-svn: 372000
2019-09-16 15:19:56 +00:00
Oliver Cruickshank cd1a0b9271 [ARM] Add patterns for CTLZ on MVE
CTLZ intrinsic can use the VCLS instruction on MVE, which produces
better results than expanding.

llvm-svn: 371999
2019-09-16 15:19:49 +00:00
David Green ce7328cb61 [ARM] Fold VCMP into VPT
MVE has VPT instructions, which perform the duties of both a VCMP and a VPST in
a single instruction, performing the compare and starting the VPT block in one.
This teaches the MVEVPTBlockPass to fold them, searching back through the
basicblock for a valid VCMP and creating the VPT from its operands.

There are some changes to the VPT instructions to accommodate this, altering
the order of the operands to match the VCMP better, and changing P0 register
defs to be VPR defs, as is used in other places.

Differential Revision: https://reviews.llvm.org/D66577

llvm-svn: 371982
2019-09-16 13:02:41 +00:00
David Green b325c05732 [ARM] Masked loads and stores
Masked loads and store fit naturally with MVE, the instructions being easily
predicated. This adds lowering for the simple cases of masked loads and stores.
It does not yet deal with widening/narrowing or pre/post inc, and so is
currently behind an option.

The llvm masked load intrinsic will accept a "passthru" value, dictating the
values used for the zero masked lanes. In MVE the instructions write 0 to the
zero predicated lanes, so we need to match a passthru that isn't 0 (or undef)
with a select instruction to pull in the correct data after the load.

Differential Revision: https://reviews.llvm.org/D67186

llvm-svn: 371932
2019-09-15 14:14:47 +00:00
David Green b7b7f26220 [ARM] Add earlyclobber for cross beat MVE instructions
rL367544 added @earlyclobbers for the MVE VREV64 instruction. This adds the
same for a number of other 32bit instructions that are similarly unpredictable
if the destination equals the source (due to the cross beat nature of the
instructions).
This includes:
  VCADD.f32
  VCADD.i32
  VCMUL.f32
  VHCADD.s32
  VMULLT/B.s/u32
  VQDMLADH{X}.s32
  VQRDMLADH{X}.s32
  VQDMLSDH{X}.s32
  VQRDMLSDH{X}.s32
  VQDMULLT/B.s32 with Qm and Rm

No tests here as this would require intrinsics (or very interesting codegen) to
manifest. The tests will follow naturally as the intrinsics are added.

Differential Revision: https://reviews.llvm.org/D67462

llvm-svn: 371838
2019-09-13 11:20:17 +00:00
Sam Tebbs 1572b68509 [ARM] Add support for MVE vmaxv and vminv
This patch adds vecreduce_smax, vecredude_umax, vecreduce_smin, vecreduce_umin and selection for vmaxv and minv.

Differential Revision: https://reviews.llvm.org/D66413

llvm-svn: 371827
2019-09-13 09:11:46 +00:00
Guillaume Chatelet af11cc7eb5 [Alignment] Move OffsetToAlignment to Alignment.h
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, JDevlieghere, alexshap, rupprecht, jhenderson

Subscribers: sdardis, nemanjai, hiraditya, kbarton, jakehehrlich, jrtc27, MaskRay, atanasyan, jsji, seiya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D67499

llvm-svn: 371742
2019-09-12 15:20:36 +00:00
Guillaume Chatelet 97264366fb [Alignment][NFC] use llvm::Align for AsmPrinter::EmitAlignment
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: dschuff, sdardis, nemanjai, hiraditya, kbarton, jrtc27, MaskRay, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67443

llvm-svn: 371616
2019-09-11 13:37:35 +00:00
Guillaume Chatelet 48904e9452 [Alignment] Use llvm::Align in MachineFunction and TargetLowering - fixes mir parsing
Summary:
This catches malformed mir files which specify alignment as log2 instead of pow2.
See https://reviews.llvm.org/D65945 for reference,

This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: MatzeB, qcolombet, dschuff, arsenm, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, s.egerton, pzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67433

llvm-svn: 371608
2019-09-11 11:16:48 +00:00
Guillaume Chatelet b6722af068 [Alignment] Use Align for TargetLowering::MinStackArgumentAlignment
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: sdardis, nemanjai, hiraditya, kbarton, jrtc27, MaskRay, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67288

llvm-svn: 371498
2019-09-10 09:01:18 +00:00
David Green 2b7089949e [ARM] Fix loads and stores for predicate vectors
These predicate vectors can usually be loaded and stored with a single
instruction, a VSTR_P0. However this instruction will store the entire P0
predicate, 16 bits, zeroextended to 32bits. Each lane of the the
v4i1/v8i1/v16i1 representing 4/2/1 bits.

As far as I understand, when llvm says "store this v4i1", it really does need
to store 4 bits (or 8, that being the size of a byte, with this bottom 4 as the
interesting bits). For example a bitcast from a v8i1 to a i8 is defined as a
store followed by a load, which is how the code is expanded.

So this instead lowers the v4i1/v8i1 load/store through some shuffles to get
the bits into the correct positions. This, as you might imagine, is not as
efficient as a single instruction. But I believe it is needed for correctness.
v16i1 equally should not load/store 32bits, only storing the 16bits of data.
Stack loads/stores are still using the VSTR_P0 (as can be seen by the test not
changing). This is fine as they are self-consistent, it is only "externally
observable loads/stores" (from our point of view) that need to be corrected.

Differential revision: https://reviews.llvm.org/D67085

llvm-svn: 371419
2019-09-09 16:35:49 +00:00
Simon Tatham 0e48bd24e2 [ARM] Remove some spurious MVE reduction instructions.
The family of 'dual-accumulating' vector multiply-add instructions
(VMLADAV, VMLALDAV and VRMLALDAVH) can all operate on both signed and
unsigned integer types, and they all have an 'exchange' variant (with
an X in the name) that modifies which pairs of vector lanes in the two
inputs are multiplied together. But there's a clause in the spec that
says that the X variants //don't// operate on unsigned integer types,
only signed. You can have X, or unsigned, or neither, but not both.

We didn't notice that clause when we implemented the MC support for
these instructions, so LLVM believes that things like VMLADAVX.U8 do
exist, contradicting the spec. Here I fix that by conditioning them
out in Tablegen.

In order to do that, I've reversed the nesting order of the Tablegen
multiclasses for those instructions. Previously, the innermost
multiclass generated the X and not-X variants, and the one outside
that generated the A and not-A variants. Now X is done by the outer
multiclass, which allows me to bypass that one when I only want the
two not-X variants.

Changing the multiclass nesting order also changes the names of the
instruction ids unless I make a special effort not to. I decided that
while I was changing them anyway I'd make them look nicer; so now the
instructions have names like MVE_VMLADAVs32 or MVE_VMLADAVaxs32,
instead of cumbersome _noacc_noexch suffixes.

The corresponding multiply-subtract instructions are unaffected. Those
don't accept unsigned types at all, either in the spec or in LLVM.

Reviewers: ostannard, dmgreen

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67214

llvm-svn: 371405
2019-09-09 15:17:26 +00:00
Sam Parker 1ad508e8e2 [ARM][MVE] VCTP instruction selection
Add codegen support for vctp{8,16,32}.

Differential Revision: https://reviews.llvm.org/D67344

llvm-svn: 371395
2019-09-09 12:54:47 +00:00
David Green d936a6301b [ARM] Prevent generating NEON stack accesses under MVE.
We should not be generating Neon stack loads/stores even for these large
registers.

No test here because my understanding is we will only generate these QQPR regs
for intrinsics and VLDn's. The tests will follow once those are available.

Differential revision: https://reviews.llvm.org/D67169

llvm-svn: 371386
2019-09-09 10:46:25 +00:00
Oliver Stannard 6b9aedaec6 [ARM][MVE] Decoding of uqrshl and sqrshl accepts unpredictable encodings
Specify the Unpredictable bits, and return softfails when appropriate.

Patch by Mark Murray!

Differential revision: https://reviews.llvm.org/D66939

llvm-svn: 371374
2019-09-09 08:50:28 +00:00
Sam Parker c363deb575 [ARM][ParallelDSP] Fix for sext input
The incoming accumulator value can be discovered through a sext, in
which case there will be a mismatch between the input and the result.
So sign extend the accumulator input if we're performing a 64-bit mac.

Differential Revision: https://reviews.llvm.org/D67220

llvm-svn: 371370
2019-09-09 08:39:14 +00:00
David Green df2501adca [ARM] Remove declaration of unimplemented function. NFC.
llvm-svn: 371331
2019-09-08 13:13:15 +00:00
Simon Pilgrim d7d8bb937a Fix MSVC "32-bit shift implicitly converted to 64 bits" warnings. NFCI.
llvm-svn: 371302
2019-09-07 11:04:04 +00:00
Teresa Johnson 9c27b59cec Change TargetLibraryInfo analysis passes to always require Function
Summary:
This is the first change to enable the TLI to be built per-function so
that -fno-builtin* handling can be migrated to use function attributes.
See discussion on D61634 for background. This is an enabler for fixing
handling of these options for LTO, for example.

This change should not affect behavior, as the provided function is not
yet used to build a specifically per-function TLI, but rather enables
that migration.

Most of the changes were very mechanical, e.g. passing a Function to the
legacy analysis pass's getTLI interface, or in Module level cases,
adding a callback. This is similar to the way the per-function TTI
analysis works.

There was one place where we were looking for builtins but not in the
context of a specific function. See FindCXAAtExit in
lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround
could provide the wrong behavior in some corner cases. Suggestions
welcome.

Reviewers: chandlerc, hfinkel

Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66428

llvm-svn: 371284
2019-09-07 03:09:36 +00:00
Oliver Cruickshank a050307c05 [ARM] Add patterns for VSUB with q and r registers
Added patterns for VSUB to support q and r registers, which reduces
pressure on q registers.

llvm-svn: 371231
2019-09-06 17:02:42 +00:00
Oliver Cruickshank 3aed95af4e [ARM] Add patterns for VADD with q and r registers
Added support for VADD to use q and r registers, which reduces pressure
on q registers.

llvm-svn: 371230
2019-09-06 17:02:35 +00:00
Oliver Cruickshank 9bf27928e1 [ARM] Add patterns for VMUL with q and r registers
Added support for VMUL to use an r register, this reduces pressure on
the q registers.

llvm-svn: 371229
2019-09-06 17:02:21 +00:00
Sam Tebbs f1cdd95a2f [ARM] Sink add/mul(shufflevector(insertelement())) for MVE instruction selection
This patch sinks add/mul(shufflevector(insertelement())) into the basic block in which they are used so that they can then be selected together.

This is useful for various MVE instructions, such as vmla and others that take R registers.

Loop tests have been added to the vmla test file to make sure vmlas are generated in loops.

Differential revision: https://reviews.llvm.org/D66295

llvm-svn: 371218
2019-09-06 16:01:32 +00:00
Guillaume Chatelet 9fcf066d0c [Alignment][NFC] Use Align with TargetLowering::setPrefLoopAlignment
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: nemanjai, hiraditya, kbarton, MaskRay, jsji, ychen, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67278

llvm-svn: 371210
2019-09-06 14:51:15 +00:00
Guillaume Chatelet 4fc3ad9e13 [Alignment][NFC] Use Align with TargetLowering::setMinFunctionAlignment
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jyknight, sdardis, nemanjai, javed.absar, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, s.egerton, pzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67229

llvm-svn: 371200
2019-09-06 12:48:34 +00:00
Sam Parker 312409e464 [ARM] MVE Tail Predication
The MVE and LOB extensions of Armv8.1m can be combined to enable
'tail predication' which removes the need for a scalar remainder
loop after vectorization. Lane predication is performed implicitly
via a system register. The effects of predication is described in
Section B5.6.3 of the Armv8.1-m Arch Reference Manual, the key points
being:
- For vector operations that perform reduction across the vector and
  produce a scalar result, whether the value is accumulated or not.
- For non-load instructions, the predicate flags determine if the
  destination register byte is updated with the new value or if the
  previous value is preserved.
- For vector store instructions, whether the store occurs or not.
- For vector load instructions, whether the value that is loaded or
  whether zeros are written to that element of the destination
  register.

This patch implements a pass that takes a hardware loop, containing
masked vector instructions, and converts it something that resembles
an MVE tail predicated loop. Currently, if we had code generation,
we'd generate a loop in which the VCTP would generate the predicate
and VPST would then setup the value of VPR.PO. The loads and stores
would be placed in VPT blocks so this is not tail predication, but
normal VPT predication with the predicate based upon a element
counting induction variable. Further work needs to be done to finally
produce a true tail predicated loop.

Because only the loads and stores are predicated, in both the LLVM IR
and MIR level, we will restrict support to only lane-wise operations
(no horizontal reductions). We will perform a final check on MIR
during loop finalisation too.

Another restriction, specific to MVE, is that all the vector
instructions need operate on the same number of elements. This is
because predication is performed at the byte level and this is set
on entry to the loop, or by the VCTP instead.

Differential Revision: https://reviews.llvm.org/D65884

llvm-svn: 371179
2019-09-06 08:24:41 +00:00
David Candler a59bffb576 [ARM] Add support for the s,j,x,N,O inline asm constraints
A number of inline assembly constraints are currently supported by LLVM, but rejected as invalid by Clang:

Target independent constraints:

s: An integer constant, but allowing only relocatable values

ARM specific constraints:

j: An immediate integer between 0 and 65535 (valid for MOVW)
x: A 32, 64, or 128-bit floating-point/SIMD register: s0-s15, d0-d7, or q0-q3
N: An immediate integer between 0 and 31 (Thumb1 only)
O: An immediate integer which is a multiple of 4 between -508 and 508. (Thumb1 only)

This patch adds support to Clang for the missing constraints along with some checks to ensure that the constraints are used with the correct target and Thumb mode, and that immediates are within valid ranges (at least where possible). The constraints are already implemented in LLVM, but just a couple of minor corrections to checks (V8M Baseline includes MOVW so should work with 'j', 'N' and 'O' shouldn't be valid in Thumb2) so that Clang and LLVM are in line with each other and the documentation.

Differential Revision: https://reviews.llvm.org/D65863

Change-Id: I18076619e319bac35fbb60f590c069145c9d9a0a
llvm-svn: 371079
2019-09-05 15:17:25 +00:00
David Green 83a3341246 [ARM] Fixup the creation of VPT blocks
This attempts to just fix the creation of VPT blocks, fixing up the iterating,
which instructions are considered in the bundle, and making sure that we do not
overrun the end of the block.

Differential Revision: https://reviews.llvm.org/D67219

llvm-svn: 371064
2019-09-05 13:37:04 +00:00
Guillaume Chatelet aff45e4b23 [LLVM][Alignment] Make functions using log of alignment explicit
Summary:
This patch renames functions that takes or returns alignment as log2, this patch will help with the transition to llvm::Align.
The renaming makes it explicit that we deal with log(alignment) instead of a power of two alignment.
A few renames uncovered dubious assignments:

 - `MirParser`/`MirPrinter` was expecting powers of two but `MachineFunction` and `MachineBasicBlock` were using deal with log2(align). This patch fixes it and updates the documentation.
 - `MachineBlockPlacement` exposes two flags (`align-all-blocks` and `align-all-nofallthru-blocks`) supposedly interpreted as power of two alignments, internally these values are interpreted as log2(align). This patch updates the documentation,
 - `MachineFunctionexposes` exposes `align-all-functions` also interpreted as power of two alignment, internally this value is interpreted as log2(align). This patch updates the documentation,

Reviewers: lattner, thegameg, courbet

Subscribers: dschuff, arsenm, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, Jim, s.egerton, llvm-commits, courbet

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65945

llvm-svn: 371045
2019-09-05 10:00:22 +00:00
Sam Parker fea532230b [ARM][ParallelDSP] SExt mul for accumulation
For any unpaired muls, we accumulate them as an input to the
reduction. Check the type of the mul and perform a sext if the
existing accumlator input type is not the same.

Differential Revision: https://reviews.llvm.org/D66993

llvm-svn: 370851
2019-09-04 08:41:34 +00:00
Amara Emerson fbaf425b79 [GlobalISel][CallLowering] Add support for splitting types according to calling conventions.
On AArch64, s128 types have to be split into s64 GPRs when passed as arguments.
This change adds the generic support in call lowering for dealing with multiple
registers, for incoming and outgoing args.

Support for splitting for return types not yet implemented.

Differential Revision: https://reviews.llvm.org/D66180

llvm-svn: 370822
2019-09-03 21:42:28 +00:00
Reid Kleckner b2d10cf22e [MC] Pass through .code16/32/64 and .syntax unified for COFF
These flags should simply be passed through to the target, which will do
the right thing. Add an MC/X86 test that uses these directives with the
three primary object file formats and shows that they disassemble the
same everywhere.

There is a missing test for .code32 on Windows ARM, since I'm not sure
exactly how to construct one.

Fixes PR43203

llvm-svn: 370805
2019-09-03 18:16:52 +00:00
David Green 2f3574c168 [ARM] Ignore Implicit CPSR regs when lowering from Machine to MC operands
The code here seems to date back to r134705, when tablegen lowering was first
being added. I don't believe that we need to include CPSR implicit operands on
the MCInst. This now works more like other backends (like AArch64), where all
implicit registers are skipped.

This allows the AliasInst for CSEL's to match correctly, as can be seen in the
test changes.

Differential revision: https://reviews.llvm.org/D66703

llvm-svn: 370745
2019-09-03 11:30:54 +00:00
David Green 61973d978b [ARM] Invert CSEL predicates if the opposite is a simpler constant to materialise
This moves ConstantMaterializationCost into ARMBaseInstrInfo so that it can
also be used in ISel Lowering, adding codesize values to the computed costs, to
be able to compare either approximate instruction counts or codesize costs.

It also adds a HasLowerConstantMaterializationCost, which compares the
ConstantMaterializationCost of two values, returning true if the first is
smaller either in instruction count/codesize, or falling back to the other in
the case that they are equal.

This is used in constant CSEL lowering to invert the predicate if the opposite
is easier to materialise.

Differential revision: https://reviews.llvm.org/D66701

llvm-svn: 370741
2019-09-03 11:06:24 +00:00
David Green 57cc65ff47 [ARM] Generate 8.1-m CSINC, CSNEG and CSINV instructions.
Arm 8.1-M adds a number of related CSEL instructions, including CSINC, CSNEG and CSINV. These choose between two values given the content in CPSR and a condition, performing an increment, negation or inverse of the false value.

This adds some selection for them, either from constant values or patterns. It does not include CSEL directly, which is currently not always making code better. It is still useful, but we will have to check more carefully where it should and shouldn't be used.

Code by Ranjeet Singh and Simon Tatham, with some modifications from me.

Differential revision: https://reviews.llvm.org/D66483

llvm-svn: 370739
2019-09-03 10:53:07 +00:00
David Green 3e8d5f335d [ARM] Fix MVE ldst offset ranges
We were using isShiftedInt<7, Shift>(RHSC) to detect the ranges of offsets to
fold into MVE loads/stores. The instructions actually take a 7 bit unsigned
integer which is either added or subtracted. So something more like
isShiftedUInt<7, Shift>(abs(RHSC)).

Instead I've changes this to use the isScaledConstantInRange method, same as in
SelectT2AddrModeImm7Offset used by pre/post inc, which seemed to already be
getting this correct.

Differential revision: https://reviews.llvm.org/D66997

llvm-svn: 370731
2019-09-03 09:57:02 +00:00
Oliver Stannard 3be2df2418 [ARM][MVE] Decoding of VMSR doesn't diagnose some unpredictable encodings
Decoding of VMSR doesn't diagnose some unpredictable encodings, as the unpredictable bits are not correctly set.

Diff-reduce this instruction's internals WRT VMRS so I can see the differences better. Mostly this is s/src/Rt/g.

Fill in the "should-be-(0)" bits.

Designate the Unpredictable{} bits for both VMRS and VMSR.

Patch by Mark Murray!

Differential revision: https://reviews.llvm.org/D66938

llvm-svn: 370729
2019-09-03 09:55:30 +00:00
Oliver Stannard 39bf484d92 Bug fix on function epilog optimization (ARM backend)
To save a 'add sp,#val' instruction by adding registers to the final pop instruction,
the first register transferred by this pop instruction need to be found.
If the function to be optimized has a non-void return value, the operand list contains
r0 (implicit) which prevents the optimization to take place.
Therefore implicit register references should be skipped in the search loop,
because this registers are never popped from the stack.

Patch by Rainer Herbertz (rOptimizer)!

Differential revision: https://reviews.llvm.org/D66730

llvm-svn: 370728
2019-09-03 09:51:19 +00:00
Sam Tebbs 8b2df85d02 [ARM] Select vmla
This patch adds vmla selection.

Differential revision: https://reviews.llvm.org/D66297

llvm-svn: 370704
2019-09-03 08:17:46 +00:00