Commit Graph

9103 Commits

Author SHA1 Message Date
Artyom Skrobov 40a4f40679 [ARM] Recommit the glueless lowering of addc/adde in Thumb1,
including the amended (no UB anymore) fix for adding/subtracting -2147483648.

This reverts r298328 "[ARM] Revert r297443 and r297820."
and partially reverts r297842 "Revert "[Thumb1] Fix the bug when adding/subtracting -2147483648""

llvm-svn: 298417
2017-03-21 18:39:41 +00:00
Reid Kleckner b518054b87 Rename AttributeSet to AttributeList
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.

Rename AttributeSetImpl to AttributeListImpl to follow suit.

It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.

Reviewers: sanjoy, javed.absar, chandlerc, pete

Reviewed By: pete

Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits

Differential Revision: https://reviews.llvm.org/D31102

llvm-svn: 298393
2017-03-21 16:57:19 +00:00
Sanne Wouda 2409c6403d [ARM] [Assembler] Support negative immediates for A32, T32 and T16
Summary:
To support negative immediates for certain arithmetic instructions, the
instruction is converted to the inverse instruction with a negated (or inverted)
immediate. For example, "ADD r0, r1, #FFFFFFFF" cannot be encoded as an ADD
instruction.  However, "SUB r0, r1, #1" is equivalent.

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

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

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

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

Reviewed By: javed.absar

Subscribers: aadg, aemerson, llvm-commits

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

llvm-svn: 298380
2017-03-21 14:59:17 +00:00
Eli Friedman 76732acc23 [ARM] Revert r297443 and r297820.
The glueless lowering of addc/adde in Thumb1 has known serious
miscompiles (see https://reviews.llvm.org/D31081), and r297820
causes an infinite loop for certain constructs.  It's not
clear when they will be fixed, so let's just take them out
of the tree for now.

(I resolved a small conflict with r297453.)

llvm-svn: 298328
2017-03-21 00:26:39 +00:00
Vadzim Dambrouski ba789cbd3d [ARM] Fix PR32130: Handle promotion of zero sized constants.
The special case of zero sized values was previously not handled correctly.
This patch handles this by not promoting if the size is zero.

Patch by Tim Neumann.

Differential Revision: https://reviews.llvm.org/D31116

llvm-svn: 298320
2017-03-20 22:59:57 +00:00
Diana Picus d79253a9f7 [GlobalISel] Use the correct calling conv for calls
This commit adds a parameter that lets us pass in the calling convention
of the call to CallLowering::lowerCall. This allows us to handle
situations where the calling convetion of the callee is different from
that of the caller.

Differential Revision: https://reviews.llvm.org/D31039

llvm-svn: 298254
2017-03-20 14:40:18 +00:00
Matthias Braun e6ff30b696 ExecutionDepsFix: Let targets specialize the pass; NFC
Let targets specialize the pass with the register class so we can get a
parameterless default constructor and can put the pass into the pass
registry to enable testing with -run-pass=.

llvm-svn: 298184
2017-03-18 05:08:58 +00:00
Matthias Braun e9f8209e87 ExecutionDepsFix: Normalize names; NFC
Normalize ExeDepsFix, execution-fix, ExecutionDependencyFix and
ExecutionDepsFix to the last one.

llvm-svn: 298183
2017-03-18 05:05:40 +00:00
Nirav Dave ac6081cb67 Make library calls sensitive to regparm module flag (Fixes PR3997).
Reviewers: mkuper, rnk

Subscribers: mehdi_amini, jyknight, aemerson, llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D27050

llvm-svn: 298179
2017-03-18 00:44:07 +00:00
Nirav Dave 6de2c77944 Capitalize ArgListEntry fields. NFC.
llvm-svn: 298178
2017-03-18 00:43:57 +00:00
Andre Vieira 913ffeb5ba [ARM] Fix triple format in test branch disassemble test
Fixing triple format in the tests added for the branch label fix for Thumb
Targets. Also recommitting previously approved patch, see
https://reviews.llvm.org/D30943.

Reviewed by: samparker

Differential Revision: https://reviews.llvm.org/D30987

llvm-svn: 298056
2017-03-17 09:37:10 +00:00
Eli Friedman da228fee0c [ARM] Use alias analysis in ARMPreAllocLoadStoreOpt.
This allows the optimization to rearrange loads and stores more
aggressively. This doesn't really affect performance, but it helps
codesize.

Differential Revision: https://reviews.llvm.org/D30839

llvm-svn: 298021
2017-03-17 00:34:26 +00:00
Reid Kleckner 45707d4d5a Remove getArgumentList() in favor of arg_begin(), args(), etc
Users often call getArgumentList().size(), which is a linear way to get
the number of function arguments. arg_size(), on the other hand, is
constant time.

In general, the fact that arguments are stored in an iplist is an
implementation detail, so I've removed it from the Function interface
and moved all other users to the argument container APIs (arg_begin(),
arg_end(), args(), arg_size()).

Reviewed By: chandlerc

Differential Revision: https://reviews.llvm.org/D31052

llvm-svn: 298010
2017-03-16 22:59:15 +00:00
Matthias Braun e959544517 TargetInstrInfo: Provide default implementation of isTailCall().
In fact this default implementation should be the only implementation,
keep it virtual for now to accomodate targets that don't model flags
correctly.

Differential Revision: https://reviews.llvm.org/D30747

llvm-svn: 297980
2017-03-16 20:02:30 +00:00
Tim Northover 0d98b03b9f ARM: avoid clobbering register in v6 jump-table expansion.
If we got unlucky with register allocation and actual constpool placement, we
could end up producing a tTBB_JT with an index that's already been clobbered.

Technically, we might be able to fix this situation up with a MOV, but I think
the constant islands pass is complex enough without having to deal with more
weird edge-cases.

llvm-svn: 297871
2017-03-15 18:38:13 +00:00
Sanjay Patel fa929a2134 Cyle -> Cycle; NFCI
llvm-svn: 297846
2017-03-15 15:37:42 +00:00
Artyom Skrobov e72e1ba434 Revert "[Thumb1] Fix the bug when adding/subtracting -2147483648"
This reverts r297820 which apparently fails on A15 hosts.

llvm-svn: 297842
2017-03-15 14:50:43 +00:00
Sam Parker db20d48336 Reverting r297821 due to breaking lld test.
llvm-svn: 297838
2017-03-15 14:06:42 +00:00
Sam Parker 274472f7c5 [ARM] Fix for branch label disassembly for Thumb
Different MCInstrAnalysis classes for arm and thumb mode, each with
their own evaluateBranch implementation. I added a test case and
fixed the coff-relocations test to use '<label>:' rather than
'<label>' in the CHECK-LABEL entries, since the ones without the
colon would match branch targets. Might be worth noticing that
llvm-objdump does not lookup the relocation and thus assigns it a
target depending on the encoded immediate which #0, so it thinks it
branches to the next instruction.

Committed on behalf of Andre Vieira (avieira).

Differential Revision: https://reviews.llvm.org/D30943

llvm-svn: 297821
2017-03-15 10:21:23 +00:00
Artyom Skrobov 3fa5fd1dd2 [Thumb1] Fix the bug when adding/subtracting -2147483648
Differential Revision: https://reviews.llvm.org/D30829

llvm-svn: 297820
2017-03-15 10:19:16 +00:00
Sam Parker 654cb8263a [ARM] Enable SMLAL[B|T] isel
Enable the selection of the 64-bit signed multiply accumulate
instructions which operate on 16-bit operands. These are enabled for
ARMv5TE onwards for ARM and for V6T2 and other DSP enabled Thumb
architectures.

Differential Revision: https://reviews.llvm.org/D30044

llvm-svn: 297809
2017-03-15 08:27:11 +00:00
Daniel Sanders 8a4bae9993 [globalisel][tblgen] Add support for ComplexPatterns
Summary:
Adds a new kind of MachineOperand: MO_Placeholder.
This operand must not appear in the MIR and only exists as a way of
creating an 'uninitialized' operand until a matcher function overwrites it.

Depends on D30046, D29712

Reviewers: t.p.northover, ab, rovka, aditya_nandakumar, javed.absar, qcolombet

Reviewed By: qcolombet

Subscribers: dberris, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D30089

llvm-svn: 297782
2017-03-14 21:32:08 +00:00
Evgeniy Stepanov 43dcf4d330 Fix asm printing of associated sections.
Make MCSectionELF::AssociatedSection be a link to a symbol, because
that's how it works in the assembly, and use it in the asm printer.

llvm-svn: 297769
2017-03-14 19:28:51 +00:00
Eli Friedman caea769f11 [ARM] Replace some C++ selection code with TableGen patterns. NFC.
Differential Revision: https://reviews.llvm.org/D30794

llvm-svn: 297768
2017-03-14 18:43:37 +00:00
Artyom Skrobov 2de256642b Fix typo in comment
llvm-svn: 297742
2017-03-14 14:13:19 +00:00
Oliver Stannard 6ee22c41f8 [ARM] Diagnose ARM MOVT without :lower16: or :upper16: expression
This instruction was missing from the list of opcodes that we check, so we were
hitting an llvm_unreachable in ARMMCCodeEmitter.cpp for the ARM MOVT
instruction, rather than the diagnostic that is emitted for the other MOVW/MOVT
instructions.

Differential revision: https://reviews.llvm.org/D30936

llvm-svn: 297739
2017-03-14 13:50:10 +00:00
Artyom Skrobov 283316b5c0 De-duplicate the two implementations of ARMBaseInstrInfo::isProfitableToIfCvt() [NFC]
Reviewers: congh, rengolin

Subscribers: aemerson, llvm-commits

Differential Revision: https://reviews.llvm.org/D30934

llvm-svn: 297738
2017-03-14 13:38:45 +00:00
Sam Parker 916b1ba617 [ARM] Move SMULW[B|T] isel to DAG Combine
Create nodes for smulwb and smulwt and move their selection from
DAGToDAG to DAG combine. smlawb and smlawt can then be selected
using tablegen. Added some helper functions to detect shift patterns
as well as a wrapper around SimplifyDemandBits. Added a couple of
extra tests.

Differential Revision: https://reviews.llvm.org/D30708

llvm-svn: 297716
2017-03-14 09:13:22 +00:00
Nirav Dave 54e22f33d9 In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting with compiler time improvements

    Recommitting after fixup of 32-bit aliasing sign offset bug in DAGCombiner.

    * Simplify Consecutive Merge Store Candidate Search

    Now that address aliasing is much less conservative, push through
    simplified store merging search and chain alias analysis which only
    checks for parallel stores through the chain subgraph. This is cleaner
    as the separation of non-interfering loads/stores from the
    store-merging logic.

    When merging stores search up the chain through a single load, and
    finds all possible stores by looking down from through a load and a
    TokenFactor to all stores visited.

    This improves the quality of the output SelectionDAG and the output
    Codegen (save perhaps for some ARM cases where we correctly constructs
    wider loads, but then promotes them to float operations which appear
    but requires more expensive constant generation).

    Some minor peephole optimizations to deal with improved SubDAG shapes (listed below)

    Additional Minor Changes:

      1. Finishes removing unused AliasLoad code

      2. Unifies the chain aggregation in the merged stores across code
         paths

      3. Re-add the Store node to the worklist after calling
         SimplifyDemandedBits.

      4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
         arbitrary, but seems sufficient to not cause regressions in
         tests.

      5. Remove Chain dependencies of Memory operations on CopyfromReg
         nodes as these are captured by data dependence

      6. Forward loads-store values through tokenfactors containing
          {CopyToReg,CopyFromReg} Values.

      7. Peephole to convert buildvector of extract_vector_elt to
         extract_subvector if possible (see
         CodeGen/AArch64/store-merge.ll)

      8. Store merging for the ARM target is restricted to 32-bit as
         some in some contexts invalid 64-bit operations are being
         generated. This can be removed once appropriate checks are
         added.

    This finishes the change Matt Arsenault started in r246307 and
    jyknight's original patch.

    Many tests required some changes as memory operations are now
    reorderable, improving load-store forwarding. One test in
    particular is worth noting:

      CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store
      forwarding converts a load-store pair into a parallel store and
      a memory-realized bitcast of the same value. However, because we
      lose the sharing of the explicit and implicit store values we
      must create another local store. A similar transformation
      happens before SelectionDAG as well.

    Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle

llvm-svn: 297695
2017-03-14 00:34:14 +00:00
Artyom Skrobov bf19d4bc29 [Thumb1] combine ADDC/SUBC with a negative immediate
Summary: This simple optimization has been split out of https://reviews.llvm.org/D30400

Reviewers: efriedma, jmolloy

Subscribers: llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D30829

llvm-svn: 297682
2017-03-13 22:36:14 +00:00
Diana Picus 94db2e288b [ARM] GlobalISel: Support SP in regbankselect
We used to hit an unreachable in getRegBankFromRegClass when dealing with the
stack pointer. This commit adds support for the GPRsp reg class.

llvm-svn: 297621
2017-03-13 14:28:34 +00:00
Sjoerd Meijer aea3a990a2 ARMDisassembler: loop over ARM decode tables
Loop over the ARM decode tables; this is a clean-up to reduce some code
duplication.

Differential Revision: https://reviews.llvm.org/D30814

llvm-svn: 297608
2017-03-13 09:41:10 +00:00
Artyom Skrobov 94fb0bb65f imm_comp_XFORM (defined in ARMInstrThumb.td) duplicates imm_not_XFORM (defined in ARMInstrInfo.td)
Reviewers: grosbach, rengolin, jmolloy

Reviewed By: jmolloy

Subscribers: aemerson, llvm-commits

Differential Revision: https://reviews.llvm.org/D30782

llvm-svn: 297456
2017-03-10 13:21:12 +00:00
Artyom Skrobov 0cc80c1f5a Refactor the multiply-accumulate combines to act on
ARMISD::ADD[CE] nodes, instead of the generic ISD::ADD[CE].

Summary:
This allows for some simplification because the combines
are no longer limited to just one go at the node before
it gets legalized into an ARM target-specific one.

Reviewers: jmolloy, rogfer01

Subscribers: aemerson, llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D30401

llvm-svn: 297453
2017-03-10 12:41:33 +00:00
Artyom Skrobov 0c93ceb5d8 For Thumb1, lower ADDC/ADDE/SUBC/SUBE via the glueless ARMISD nodes,
same as already done for ARM and Thumb2.

Reviewers: jmolloy, rogfer01, efriedma

Subscribers: aemerson, llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D30400

llvm-svn: 297443
2017-03-10 07:40:27 +00:00
Sjoerd Meijer 7f1a982d3d [ARM] remove FIXMEs and add vcmp MC test
Minor cleanup in ARMInstrVFP.td: removed some FIXMEs and added a MC test for
vcmp that was actually missing.

Differential Revision: https://reviews.llvm.org/D30745

llvm-svn: 297376
2017-03-09 13:28:37 +00:00
John Brawn eba9fdac7e [ARM] Correct handling of LSL #0 in an IT block
The check for LSL #0 in an IT block was checking if operand 4 was zero, but
operand 4 is the condition code operand so it was actually checking for LSLEQ.
Fix this by checking operand 3, which really is the immediate operand, and add
some tests.

Differential Revision: https://reviews.llvm.org/D30692

llvm-svn: 297142
2017-03-07 14:42:03 +00:00
Ranjeet Singh 3d0af578cc [ARM] Reapply r296865 "[ARM] fpscr read/write intrinsics not aware of each other""
The original patch r296865 was reverted as it broke the chromium builds for
Android https://bugs.llvm.org/show_bug.cgi?id=32134, this patch reapplies
r296865 with a fix to make sure it doesn't cause the build regression.

The problem was that intrinsic selection on int_arm_get_fpscr was failing in
ISel this was because the code to manually select this intrinsic still thought
it was the version with no side-effects (INTRINSIC_WO_CHAIN) which is wrong as
it doesn't semantically match the definition in the tablegen code which says it
does have side-effects, I've fixed this by updating the intrinsic type to
INTRINSIC_W_CHAIN (has side-effects). I've also added a test for this based on
Hans original reproducer.

Differential Revision: https://reviews.llvm.org/D30645

llvm-svn: 297137
2017-03-07 11:17:53 +00:00
Artyom Skrobov 1388e2f792 In Thumb1, materialize a move between low registers as a `movs`, if CPSR isn't live.
Summary: Previously, it had always been materialized as a push/pop sequence.

Reviewers: labrinea, jroelofs

Reviewed By: jroelofs

Subscribers: llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D30648

llvm-svn: 297134
2017-03-07 09:38:16 +00:00
Tim Northover c2c545b8f7 GlobalISel: restrict G_EXTRACT instruction to just one operand.
A bit more painful than G_INSERT because it was more widely used, but this
should simplify the handling of extract operations in most locations.

llvm-svn: 297100
2017-03-06 23:50:28 +00:00
Krzysztof Parzyszek cc31871dc4 Make TargetInstrInfo::isPredicable take a const reference, NFC
llvm-svn: 296901
2017-03-03 18:30:54 +00:00
Chandler Carruth ce52b80744 [SDAG] Revert r296476 (and r296486, r296668, r296690).
This patch causes compile times for some patterns to explode. I have
a (large, unreduced) test case that slows down by more than 20x and
several test cases slow down by 2x. I'm sending some of the test cases
directly to Nirav and following up with more details in the review log,
but this should unblock anyone else hitting this.

llvm-svn: 296862
2017-03-03 10:02:25 +00:00
Eli Friedman bb821276d0 [ARM] Fix insert point for store rescheduling.
In ARMPreAllocLoadStoreOpt::RescheduleOps, LastOp should be the last
operation which we want to merge. If we break out of the loop because
an operation has the wrong offset, we shouldn't use that operation
as LastOp.

This patch fixes some cases where we would move stores to the wrong
insert point.

Re-commit with a fix to increment NumMove in the right place.

Differential Revision: https://reviews.llvm.org/D30124

llvm-svn: 296815
2017-03-02 21:39:39 +00:00
Matthew Simpson aee9771ae2 [ARM/AArch64] Update costs for interleaved accesses with wide types
After r296750, we're able to match interleaved accesses having types wider than
128 bits. This patch updates the associated TTI costs.

Differential Revision: https://reviews.llvm.org/D29675

llvm-svn: 296751
2017-03-02 15:15:35 +00:00
Matthew Simpson 1bfa159db9 [ARM/AArch64] Support wide interleaved accesses
This patch teaches (ARM|AArch64)ISelLowering.cpp to match illegal vector types
to interleaved access intrinsics as long as the types are multiples of the
vector register width. A "wide" access will now be mapped to multiple
interleave intrinsics similar to the way in which non-interleaved accesses with
illegal types are legalized into multiple accesses. I'll update the associated
TTI costs (in getInterleavedMemoryOpCost) as a follow-on.

Differential Revision: https://reviews.llvm.org/D29466

llvm-svn: 296750
2017-03-02 15:11:20 +00:00
Eli Friedman 933863ce61 Revert r296708; causing test failures on ARM hosts.
Original commit message:

[ARM] Fix insert point for store rescheduling.
    
In ARMPreAllocLoadStoreOpt::RescheduleOps, LastOp should be the last
operation which we want to merge. If we break out of the loop because
an operation has the wrong offset, we shouldn't use that operation as
LastOp.
    
This patch fixes some cases where we would sink stores for no reason.

llvm-svn: 296718
2017-03-02 00:08:50 +00:00
Eli Friedman 1c9216b003 [ARM] Fix insert point for store rescheduling.
In ARMPreAllocLoadStoreOpt::RescheduleOps, LastOp should be the last
operation which we want to merge. If we break out of the loop because
an operation has the wrong offset, we shouldn't use that operation as
LastOp.
    
This patch fixes some cases where we would sink stores for no reason.
    
Differential Revision: https://reviews.llvm.org/D30124

llvm-svn: 296708
2017-03-01 23:20:29 +00:00
Eli Friedman 28c2c0e311 [ARM] Check correct instructions for load/store rescheduling.
This code starts from the high end of the sorted vector of offsets, and
works backwards: it tries to find contiguous offsets, process them, then
pops them from the end of the vector. Most of the code agrees with this
order of processing, but one loop doesn't: it instead processes elements
from the low end of the vector (which are nodes with unrelated offsets).
Fix that loop to process the correct elements.
    
This has a few implications. One, we don't incorrectly return early when
processing multiple groups of offsets in the same block (which allows
rescheduling prera-ldst-insertpt.mir). Two, we pick the correct insert
point for loads, so they're correctly sorted (which affects the
scheduling of vldm-liveness.ll). I think it might also impact some of
the heuristics slightly.
    
Differential Revision: https://reviews.llvm.org/D30368

llvm-svn: 296701
2017-03-01 22:56:20 +00:00
Diana Picus 3841522259 clang-format r296631
Apparently I forgot to run it after fixing up some things...

llvm-svn: 296634
2017-03-01 15:54:21 +00:00
Diana Picus 9c52309b37 [ARM] GlobalISel: Lower call params that need extensions
Lower i1, i8 and i16 call parameters by extending them before storing them on
the stack. Also make sure we encode the correct, extended size in the
corresponding memory operand, and that we compute the correct stack size in the
end.

The latter is a bit more complicated because we used to compute the stack size
in the getStackAddress method, based on the Size and Offset of the parameters.
However, if the last parameter is sign extended, we'd be using the wrong,
non-extended size, and we'd end up with a smaller stack than we need to hold the
extended value. Instead of hacking this up based on the value of Size in
getStackAddress, we move our stack size handling logic to assignArg, where we
have access to the CCState which knows everything we could possibly want to know
about the stack. This way we don't need to duplicate any knowledge or resort to
any ugly hacks.

On this same occasion, update the IRTranslator test to check the sizes of the
stores everywhere, not just for sign extended paramteres.

llvm-svn: 296631
2017-03-01 15:35:14 +00:00
Oliver Stannard 5d35b9e56c [ARM] Fix parsing of special register masks
This parsing code was incorrectly checking for invalid characters, so an
invalid instruction like:
  msr spsr_w, r0
would be emitted as:
  msr spsr_cxsf, r0

Differential revision: https://reviews.llvm.org/D30462

llvm-svn: 296607
2017-03-01 10:51:04 +00:00
Eli Friedman 36795239f5 [ARM] Don't generate deprecated T1 STM.
This prevents generating stm r1!, {r0, r1} on Thumb1, where value
stored for r1 is UNKONWN.

Patch by Zhaoshi Zheng.

Differential Revision: https://reviews.llvm.org/D27910

llvm-svn: 296538
2017-02-28 23:32:55 +00:00
Nirav Dave f830dec3f2 In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting after fixup of 32-bit aliasing sign offset bug in DAGCombiner.

    * Simplify Consecutive Merge Store Candidate Search

    Now that address aliasing is much less conservative, push through
    simplified store merging search and chain alias analysis which only
    checks for parallel stores through the chain subgraph. This is cleaner
    as the separation of non-interfering loads/stores from the
    store-merging logic.

    When merging stores search up the chain through a single load, and
    finds all possible stores by looking down from through a load and a
    TokenFactor to all stores visited.

    This improves the quality of the output SelectionDAG and the output
    Codegen (save perhaps for some ARM cases where we correctly constructs
    wider loads, but then promotes them to float operations which appear
    but requires more expensive constant generation).

    Some minor peephole optimizations to deal with improved SubDAG shapes (listed below)

    Additional Minor Changes:

      1. Finishes removing unused AliasLoad code

      2. Unifies the chain aggregation in the merged stores across code
         paths

      3. Re-add the Store node to the worklist after calling
         SimplifyDemandedBits.

      4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
         arbitrary, but seems sufficient to not cause regressions in
         tests.

      5. Remove Chain dependencies of Memory operations on CopyfromReg
         nodes as these are captured by data dependence

      6. Forward loads-store values through tokenfactors containing
          {CopyToReg,CopyFromReg} Values.

      7. Peephole to convert buildvector of extract_vector_elt to
         extract_subvector if possible (see
         CodeGen/AArch64/store-merge.ll)

      8. Store merging for the ARM target is restricted to 32-bit as
         some in some contexts invalid 64-bit operations are being
         generated. This can be removed once appropriate checks are
         added.

    This finishes the change Matt Arsenault started in r246307 and
    jyknight's original patch.

    Many tests required some changes as memory operations are now
    reorderable, improving load-store forwarding. One test in
    particular is worth noting:

      CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store
      forwarding converts a load-store pair into a parallel store and
      a memory-realized bitcast of the same value. However, because we
      lose the sharing of the explicit and implicit store values we
      must create another local store. A similar transformation
      happens before SelectionDAG as well.

    Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle

llvm-svn: 296476
2017-02-28 14:24:15 +00:00
Diana Picus 1ffca2aeaf [ARM] GlobalISel: Lower i32 and fp call parameters on the stack
Lower i32, float and double parameters that need to live on the stack. This
boils down to creating some G_GEPs starting from the stack pointer and storing
the values there. During the process we also keep track of the stack size and
use the final value in the ADJCALLSTACKDOWN/UP instructions.

We currently assert for smaller types, since they usually require extensions.
They will be handled in a separate patch.

llvm-svn: 296473
2017-02-28 14:17:53 +00:00
Diana Picus 5a7203a0af [ARM] GlobalISel: Select 32-bit G_CONSTANT
Put it into a register by means of a MOVi.

llvm-svn: 296471
2017-02-28 13:05:42 +00:00
Diana Picus 5b8514559e [ARM] GlobalISel: Add mapping for G_CONSTANT
Like G_FRAME_INDEX, G_CONSTANT has one register operand and one non-register
operand.

llvm-svn: 296469
2017-02-28 12:13:58 +00:00
Diana Picus e6beac6742 [ARM] GlobalISel: Legalize 32-bit constants
llvm-svn: 296468
2017-02-28 11:33:46 +00:00
Diana Picus 9d07094913 [ARM] GlobalISel: Select G_GEP
At this point, G_GEP is just an add, so we treat it exactly like a G_ADD.

llvm-svn: 296462
2017-02-28 10:14:38 +00:00
Oliver Stannard 85d4d5b493 [ARM] Diagnose PC-writing instructions in IT blocks
In Thumb2, instructions which write to the PC are UNPREDICTABLE if they are in
an IT block but not the last instruction in the block.

Previously, we only diagnosed this for LDM instructions, this patch extends the
diagnostic to cover all of the relevant instructions.

Differential Revision: https://reviews.llvm.org/D30398

llvm-svn: 296459
2017-02-28 10:04:36 +00:00
Diana Picus 566a15d749 [ARM] GlobalISel: Add reg bank mapping for G_GEP
This should be the same as the mapping for G_ADD etc.

llvm-svn: 296455
2017-02-28 09:35:10 +00:00
Diana Picus 8598b17076 [ARM] GlobalISel: Legalize G_GEP with 32-bit offsets
At the moment we're only interested in GEPs for putting call parameters on the
stack, so we'll stick to 32-bit offsets.

llvm-svn: 296452
2017-02-28 09:02:42 +00:00
Sanjay Patel ae7873fe55 [ARM] don't transform an add(ext Cond), C to select unless there's a setcc of the condition
The transform in question claims to be doing:

// fold (add (select cc, 0, c), x) -> (select cc, x, (add, x, c))

...starting in PerformADDCombineWithOperands(), but it wasn't actually checking for a setcc node
for the sext/zext patterns.

This is exactly the opposite of a transform I'd like to add to DAGCombiner's foldSelectOfConstants(),
so I was seeing infinite loops with my draft of a patch applied.

The changes in select_const.ll look positive (less instructions). The change in arm-and-tst-peephole.ll
is unrelated. We're changing the input IR in that test to preserve the intent of the test, but that's 
not affected by this code change.

Differential Revision:
https://reviews.llvm.org/D30355

llvm-svn: 296389
2017-02-27 21:30:54 +00:00
John Brawn c97b714ffb [ARM] LSL #0 is an alias of MOV
Currently we handle this correctly in arm, but in thumb we don't which leads to
an unpredictable instruction being emitted for LSL #0 in an IT block and SP not
being permitted in some cases when it should be.

For the thumb2 LSL we can handle this by making LSL #0 an alias of MOV in the
.td file, but for thumb1 we need to handle it in checkTargetMatchPredicate to
get the IT handling right. We also need to adjust the handling of
MOV rd, rn, LSL #0 to avoid generating the 16-bit encoding in an IT block. We
should also adjust it to allow SP in the same way that it is allowed in
MOV rd, rn, but I haven't done that here because it looks like it would take
quite a lot of work to get right.

Additionally correct the selection of the 16-bit shift instructions in
processInstruction, where it was checking if the two registers were equal when
it should have been checking if they were low. It appears that previously this
code was never executed and the 16-bit encoding was selected by default, but
the other changes I've done here have somehow made it start being used.

Differential Revision: https://reviews.llvm.org/D30294

llvm-svn: 296342
2017-02-27 14:40:51 +00:00
Nirav Dave 73cd0194cf Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r296252 until 256-bit operations are more efficiently generated in X86.

llvm-svn: 296279
2017-02-26 01:27:32 +00:00
Nirav Dave beabf456df In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting after fixup of 32-bit aliasing sign offset bug in DAGCombiner.

    * Simplify Consecutive Merge Store Candidate Search

    Now that address aliasing is much less conservative, push through
    simplified store merging search and chain alias analysis which only
    checks for parallel stores through the chain subgraph. This is cleaner
    as the separation of non-interfering loads/stores from the
    store-merging logic.

    When merging stores search up the chain through a single load, and
    finds all possible stores by looking down from through a load and a
    TokenFactor to all stores visited.

    This improves the quality of the output SelectionDAG and the output
    Codegen (save perhaps for some ARM cases where we correctly constructs
    wider loads, but then promotes them to float operations which appear
    but requires more expensive constant generation).

    Some minor peephole optimizations to deal with improved SubDAG shapes (listed below)

    Additional Minor Changes:

      1. Finishes removing unused AliasLoad code

      2. Unifies the chain aggregation in the merged stores across code
         paths

      3. Re-add the Store node to the worklist after calling
         SimplifyDemandedBits.

      4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
         arbitrary, but seems sufficient to not cause regressions in
         tests.

      5. Remove Chain dependencies of Memory operations on CopyfromReg
         nodes as these are captured by data dependence

      6. Forward loads-store values through tokenfactors containing
          {CopyToReg,CopyFromReg} Values.

      7. Peephole to convert buildvector of extract_vector_elt to
         extract_subvector if possible (see
         CodeGen/AArch64/store-merge.ll)

      8. Store merging for the ARM target is restricted to 32-bit as
         some in some contexts invalid 64-bit operations are being
         generated. This can be removed once appropriate checks are
         added.

    This finishes the change Matt Arsenault started in r246307 and
    jyknight's original patch.

    Many tests required some changes as memory operations are now
    reorderable, improving load-store forwarding. One test in
    particular is worth noting:

      CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store
      forwarding converts a load-store pair into a parallel store and
      a memory-realized bitcast of the same value. However, because we
      lose the sharing of the explicit and implicit store values we
      must create another local store. A similar transformation
      happens before SelectionDAG as well.

    Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle

llvm-svn: 296252
2017-02-25 11:43:58 +00:00
Diana Picus 3b99c64ba1 [ARM] GlobalISel: Select G_STORE
Same as selecting G_LOAD.

llvm-svn: 296122
2017-02-24 14:01:27 +00:00
Diana Picus 1f432f995a [ARM] GlobalISel: Add reg bank mappings for stores
Same as the ones for loads.

llvm-svn: 296115
2017-02-24 13:07:25 +00:00
Diana Picus a2b632a353 [ARM] GlobalISel: Legalize stores
Allow the same types that we allow for loads.

llvm-svn: 296108
2017-02-24 11:28:24 +00:00
Diana Picus c21d1e5d94 Revert "[ARM] GlobalISel: Legalize stores"
This reverts commit r296103 because the test broke on one of the bots. Sorry!

llvm-svn: 296104
2017-02-24 10:35:39 +00:00
Diana Picus a5f1cfd1a7 [ARM] GlobalISel: Legalize stores
Allow the same types that we allow for loads.

llvm-svn: 296103
2017-02-24 10:19:23 +00:00
Tim Northover 063a56e81c ARM: make sure FastISel bails on f64 operations for Cortex-M4.
FastISel wasn't checking the isFPOnlySP subtarget feature before emitting
double-precision operations, so it got completely invalid CodeGen for doubles
on Cortex-M4F.

The normal ISel testing wasn't spectacular either so I added a second RUN line
to improve that while I was in the area.

llvm-svn: 296031
2017-02-23 22:35:00 +00:00
Diana Picus a8cb0cd8f2 [ARM] GlobalISel: Lower call returns
Introduce a common ValueHandler for call returns and formal arguments, and
inherit two different versions for handling the differences (at the moment the
only difference is the way physical registers are marked as used).

llvm-svn: 295973
2017-02-23 14:18:41 +00:00
Diana Picus a606713c33 [ARM] GlobalISel: Lower call parameters in regs
Add support for lowering calls with parameters than can fit into regs.  Use the
same ValueHandler that we used for function returns, but rename it to match its
new, extended purpose.

llvm-svn: 295971
2017-02-23 13:25:43 +00:00
Kristof Beyls 5ac6adbb6d Fix assertion failure in ARMConstantIslandPass.
The ARMConstantIslandPass didn't have support for handling accesses to
constant island objects through ARM::t2LDRBpci instructions. This adds
support for that.

This fixes PR31997.

llvm-svn: 295964
2017-02-23 12:24:55 +00:00
Roger Ferrer Ibanez 56db97d4de [ARM] Fix constant islands pass.
The pass tries to fix a spill of LR that turns out to be unnecessary.
So it removes the tPOP but forgets to remove tPUSH.
This causes the stack be misaligned upon returning the function.

Thus, remove the tPUSH as well in this case.

Differential Revision: https://reviews.llvm.org/D30207

llvm-svn: 295816
2017-02-22 09:06:21 +00:00
Javed Absar b672722810 [ARM] Classification Improvements to ARM Sched-Models. NFCI.
This patch adds missing sched classes for Thumb2 instructions.
This has been missing so far, and as a consequence, machine
scheduler models for individual sub-targets have tended to
be larger than they needed to be. These patches should help
write schedulers better and faster in the future
for ARM sub-targets.

Reviewer: Diana Picus
Differential Revision: https://reviews.llvm.org/D29953

llvm-svn: 295811
2017-02-22 07:22:57 +00:00
Dan Gohman 18eafb6c68 [WebAssembly] Add skeleton MC support for the Wasm container format
This just adds the basic skeleton for supporting a new object file format.
All of the actual encoding will be implemented in followup patches.

Differential Revision: https://reviews.llvm.org/D26722

llvm-svn: 295803
2017-02-22 01:23:18 +00:00
Evgeniy Stepanov 1fd19c6e5d Fix PR31896.
Address of an alias of a global with offset is incorrectly lowered as an address of the global (i.e. ignoring offset).

llvm-svn: 295762
2017-02-21 20:17:34 +00:00
John Brawn a6e95e1652 [ARM] Correct SP/PC handling in t2MOVr
PC isn't allowed in the source operand of t2MOVr, so change the register class
to one without PC. SP handling is slightly trickier and changes depending on if
we're in ARMv8, so do that in checkTargetMatchPredicate.

Differential Revision: https://reviews.llvm.org/D30199

llvm-svn: 295732
2017-02-21 16:41:29 +00:00
Diana Picus 613b65696a [ARM] GlobalISel: Lower calls to void() functions
For now, we hardcode a BLX instruction, and generate an ADJCALLSTACKDOWN/UP pair
with amount 0.

llvm-svn: 295716
2017-02-21 11:33:59 +00:00
Diana Picus 1c33c9f0b0 [ARM] GlobalISel: Don't select atomic loads
There used to be a check in the IRTranslator that prevented us from having to
deal with atomic loads/stores. That check has been removed in r294993 and the
AArch64 backend was updated accordingly. This commit does the same thing for the
ARM backend.

In general, in the ARM backend we introduce fences during the atomic expand
pass, so we don't have to worry about atomics, *except* for the 32-bit ARMv8
target, which handles atomics more like AArch64. Since we don't want to worry
about that yet, just bail out of instruction selection if we find any atomic
loads.

llvm-svn: 295662
2017-02-20 14:45:58 +00:00
Artyom Skrobov 4592f6206c In Thumb1 mode, the custom lowering for ARMISD::CMPZ could never emit tADDi3
Reviewers: jmolloy, t.p.northover

Reviewed By: t.p.northover

Subscribers: t.p.northover, aemerson, rengolin, llvm-commits

Differential Revision: https://reviews.llvm.org/D30097

llvm-svn: 295478
2017-02-17 18:59:16 +00:00
Sam Parker 58af0c55d2 [ARM] Replace HasT2ExtractPack with HasDSP
Removed the HasT2ExtractPack feature and replaced its references
with HasDSP. This then allows the Thumb2 extend instructions to be
selected for ARMv8M +dsp. These instruction descriptions have also
been refactored and more target tests have been added for their isel.

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

llvm-svn: 295452
2017-02-17 15:42:44 +00:00
Diana Picus e836878bf1 [ARM] GlobalISel: Clean up some helpers
Return invalid opcodes when some of the helpers in the instruction selection
pass can't handle a given combination.

llvm-svn: 295446
2017-02-17 13:44:19 +00:00
Diana Picus 38699dbac5 [ARM] GlobalISel: Check mappings used by reg bank select
Add some asserts to make sure we're using the mappings that we think we're
using. This is to keep us from accidentally breaking functionality while moving
to TableGen'erated mappings.

llvm-svn: 295441
2017-02-17 13:14:25 +00:00
Diana Picus 7cab0786bd [ARM] GlobalISel: Use Subtarget in Legalizer
Start using the Subtarget to make decisions about what's legal. In particular,
we only mark floating point operations as legal if we have VFP2, which is
something we should've done from the very start.

llvm-svn: 295439
2017-02-17 11:25:17 +00:00
Diana Picus 1540b06ef8 [ARM] GlobalISel: Select floating point loads
llvm-svn: 295321
2017-02-16 14:10:50 +00:00
Diana Picus b1701e0b05 [ARM] GlobalISel: Select G_SEQUENCE and G_EXTRACT
Since they're only used for passing around double precision floating point
values into the general purpose registers, we'll lower them to VMOVDRR and
VMOVRRD.

llvm-svn: 295310
2017-02-16 12:19:57 +00:00
Diana Picus 6beef3c087 [ARM] GlobalISel: Select double G_FADD and copies
Just use VADDD if available, bail out if not.

llvm-svn: 295309
2017-02-16 12:19:52 +00:00
Diana Picus 9b32faa821 [ARM] GlobalISel: Assert that we don't use the FPR bank if we don't have VFP
llvm-svn: 295308
2017-02-16 11:25:09 +00:00
Diana Picus a93803b9fe [ARM] GlobalISel: Add reg bank mappings for G_SEQUENCE and G_EXTRACT
Support G_SEQUENCE and G_EXTRACT as needed for passing double precision floating
point values in the soft-fp float mode.

llvm-svn: 295306
2017-02-16 11:00:31 +00:00
Diana Picus 7f82c87022 [ARM] GlobalISel: Make the FPR bank 64-bit wide
Also add mappings for single and double precision FP, and use them for G_FADD
and G_LOAD.

llvm-svn: 295302
2017-02-16 10:12:49 +00:00
Diana Picus 21c3d8e0fc [ARM] GlobalISel: Legalize 64-bit G_FADD and G_LOAD
For now we just mark them as legal all the time and let the other passes bail
out if they can't handle it. In the future, we'll want to move more of the
brains into the legalizer.

llvm-svn: 295300
2017-02-16 09:09:49 +00:00
Diana Picus ca6a890d7f [ARM] GlobalISel: Lower double precision FP args
For the hard float calling convention, we just use the D registers.

For the soft-fp calling convention, we use the R registers and move values
to/from the D registers by means of G_SEQUENCE/G_EXTRACT. While doing so, we
make sure to honor the endianness of the target, since the CCAssignFn doesn't do
that for us.

For pure soft float targets, we still bail out because we don't support the
libcalls yet.

llvm-svn: 295295
2017-02-16 07:53:07 +00:00
James Molloy 0ae2202235 [ARM] Fix crash caused by r294945
I'd missed a creator of FCMP nodes - duplicateCmp().

Kindly and promptly reported by Gabor Ballabas, due to his CSiBE test suite.

llvm-svn: 294968
2017-02-13 17:18:00 +00:00
Sanne Wouda 490d4a6da6 [CodeGen] fix alignment of JUMPTABLE_INSTS on v8M.base
Summary:
The attached test case fails with "fatal error: error in backend:
misaligned pc-relative fixup value" as the jump table is misaligned.
The EmitAlignment existed already for ARM and Thumb-1 code, but was
missing for Thumb-2.

The test checks that the fatal error disappears when generating an obj
file, as well as checking the align directive is there when producing an
asm file.


Reviewers: rengolin, grosbach, t.p.northover, jmolloy, SjoerdMeijer, samparker

Reviewed By: samparker

Subscribers: samparker, aemerson, llvm-commits

Differential Revision: https://reviews.llvm.org/D29650

llvm-svn: 294950
2017-02-13 14:07:45 +00:00
James Molloy 92497542e7 [Thumb-1] TBB generation: spot redefinitions of index register
We match a sequence of 3-4 instructions into a tTBB pseudo. One of our checks is that
a particular register in that sequence is killed (so it can be clobbered by the pseudo).

We weren't noticing if an errant MOV or other instruction had infiltrated the
sequence we were walking. If it had, and it defined the register we've already
identified as killed, it makes it live across the tBR_JT and thus unclobberable.

Notice this case and bail out.

llvm-svn: 294949
2017-02-13 14:07:39 +00:00
James Molloy 9b3b899669 [ARM] Register ConstantIslands with the pass manager
This allows us to use -stop-before/-stop-after/-run-pass - we can now write
.mir tests.

llvm-svn: 294948
2017-02-13 14:07:25 +00:00
James Molloy d508789668 [ARM] Use VCMP, not VCMPE, for floating point equality comparisons
When generating a floating point comparison we currently unconditionally
generate VCMPE. This has the sideeffect of setting the cumulative Invalid
bit in FPSCR if any of the operands are QNaN.

It is expected that use of a relational predicate on a QNaN value should
raise Invalid. Quoting from the C standard:

  The relational and equality operators support the usual mathematical
  relationships between numeric values. For any ordered pair of numeric
  values exactly one of relationships the less, greater, equal and is true.
  Relational operators may raise the floating-point exception when argument
  values are NaNs.

The standard doesn't explicitly state the expectation for equality operators,
but the implication and obvious expectation is that equality operators
should not raise Invalid on a QNaN input, as those predicates are wholly
defined on unordered inputs (to return not equal).

Therefore, add a new operand to ARMISD::FPCMP and FPCMPZ indicating if
QNaN should raise Invalid, and pipe that through to TableGen.

llvm-svn: 294945
2017-02-13 12:32:47 +00:00
Ahmed Bougacha 8425f453ef [ARM] Make f16 interleaved accesses expensive.
There are no vldN/vstN f16 variants, even with +fullfp16.
We could use the i16 variants, but, in practice, even with +fullfp16,
the f16 sequence leading to the i16 shuffle usually gets scalarized.
We'd need to improve our support for f16 codegen before getting there.

Teach the cost model to consider f16 interleaved operations as
expensive.  Otherwise, we are all but guaranteed to end up with
a large block of scalarized vector code.

llvm-svn: 294819
2017-02-11 01:53:04 +00:00