Commit Graph

62687 Commits

Author SHA1 Message Date
Simon Pilgrim b13c6f1a9d [X86][SSE] X86TargetLowering::isBinOp - add PCMPGT
Allows narrowInsertExtractVectorBinOp to reduce vector size

llvm-svn: 364431
2019-06-26 14:34:41 +00:00
Roman Lebedev 78edfc4bf0 [NFC][InstCombine] Add shift amount reassociation in bittest tests (PR42399)
https://bugs.llvm.org/show_bug.cgi?id=42399
https://rise4fun.com/Alive/kBb
https://rise4fun.com/Alive/1SB

llvm-svn: 364430
2019-06-26 14:24:41 +00:00
Fedor Sergeev 1a3dc76186 [InlineCost] cleanup calculations of Cost and Threshold
Summary:
Doing better separation of Cost and Threshold.
Cost counts the abstract complexity of live instructions, while Threshold is an upper bound of complexity that inlining is comfortable to pay.
There are two parts:
     - huge 15K last-call-to-static bonus is no longer subtracted from Cost
       but rather is now added to Threshold.

       That makes much more sense, as the cost of inlining (Cost) is not changed by the fact
       that internal function is called once. It only changes the likelyhood of this inlining
       being profitable (Threshold).

     - bonus for calls proved-to-be-inlinable into callee is no longer subtracted from Cost
       but added to Threshold instead.

While calculations are somewhat different,  overall InlineResult should stay the same since Cost >= Threshold compares the same.

Reviewers: eraman, greened, chandlerc, yrouban, apilipenko
Reviewed By: apilipenko
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60740

llvm-svn: 364422
2019-06-26 13:24:24 +00:00
Roman Lebedev fbb2e40d5c [X86] X86DAGToDAGISel::matchBitExtract(): pattern c: truncation awareness
Summary:
The one thing of note here is that the 'bitwidth' constant (32/64) was previously pessimistic.
Given `x & (-1 >> (C - z))`, we were taking `C` to be `bitwidth(x)`, but in reality
we want `(-1 >> (C - z))` pattern to mean "low z bits must be all-ones".
And for that, `C` should be `bitwidth(-1 >> (C - z))`, i.e. of the shift operation itself.

Last pattern D does not seem to exhibit any of these truncation issues.
Although it has the opposite problem - if we extract low bits (no shift) from i64,
and then truncate to i32, then we fail to shrink this 64-bit extraction into 32-bit extraction.

Reviewers: RKSimon, craig.topper, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62806

llvm-svn: 364419
2019-06-26 12:19:47 +00:00
Roman Lebedev b0ecc1cc6b [X86] X86DAGToDAGISel::matchBitExtract(): pattern b: truncation awareness
Summary:
(Not so) boringly identical to pattern a (D62786)
Not yet sure how do deal with the last pattern c.

Reviewers: RKSimon, craig.topper, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62793

llvm-svn: 364418
2019-06-26 12:19:39 +00:00
Roman Lebedev 8b9a03973a [X86] X86DAGToDAGISel::matchBitExtract(): pattern a: truncation awareness
Summary:
Finally tying up loose ends here.

The problem is quite simple:
If we have pattern `(x >> start) &  (1 << nbits) - 1`,
and then truncate the result, that truncation will be propagated upwards,
into the `and`. And that isn't currently handled.

I'm only fixing pattern `a` here,
the same fix will be needed for patterns `b`/`c` too.

I *think* this isn't missing any extra legality checks,
since we only look past truncations. Similary, i don't think
we can get any other truncation there other than i64->i32.

Reviewers: craig.topper, RKSimon, spatel

Reviewed By: craig.topper

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62786

llvm-svn: 364417
2019-06-26 12:19:11 +00:00
Clement Courbet 2851248fa1 Revert "r364412 [ExpandMemCmp][MergeICmps] Move passes out of CodeGen into opt pipeline."
Breaks sanitizers:
    libFuzzer :: cxxstring.test
    libFuzzer :: memcmp.test
    libFuzzer :: recommended-dictionary.test
    libFuzzer :: strcmp.test
    libFuzzer :: value-profile-mem.test
    libFuzzer :: value-profile-strcmp.test

llvm-svn: 364416
2019-06-26 12:13:13 +00:00
Clement Courbet 7b3a5f0e6d [ExpandMemCmp][MergeICmps] Move passes out of CodeGen into opt pipeline.
This allows later passes (in particular InstCombine) to optimize more
cases.

One that's important to us is `memcmp(p, q, constant) < 0` and memcmp(p, q, constant) > 0.

llvm-svn: 364412
2019-06-26 11:50:18 +00:00
Simon Pilgrim c0711af7f9 [X86][AVX] combineExtractSubvector - 'little to big' extract_subvector(bitcast()) support
Ideally this needs to be a generic combine in DAGCombiner::visitEXTRACT_SUBVECTOR but there's some nasty regressions in aarch64 due to neon shuffles not handling bitcasts at all.....

llvm-svn: 364407
2019-06-26 11:21:09 +00:00
Djordje Todorovic e821e79fce [IR/DIVar] Add the flag for params that have unmodified value
Introduce the debug info flag that indicates that a parameter has unchanged
value throughout a function. This info will be used to emit the expressions
with DW_OP_entry_value.

([4/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D58034

llvm-svn: 364406
2019-06-26 11:19:26 +00:00
Mikhail Maltsev 6dcbb3161e [ARM] Handle fixup_arm_pcrel_9 correctly on big-endian targets
Summary:
The getFixupKindContainerSizeBytes function returns the size of the
instruction containing a given fixup. Currently fixup_arm_pcrel_9 is
not handled in this function, this causes an assertion failure in
the debug build and incorrect codegen in the release build.

This patch fixes the problem.

Reviewers: ostannard, simon_tatham

Reviewed By: ostannard

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63778

llvm-svn: 364404
2019-06-26 10:48:40 +00:00
Lewis Revill cf74881329 [RISCV] Add pseudo instruction for calls with explicit register
This patch adds the PseudoCALLReg instruction which allows using an
explicit register operand as the destination for the return address.

GCC can successfully parse this form of the call instruction, which
would be used for calls to functions which do not use ra as the return
address register, such as the __riscv_save libcalls. This patch forms
the first part of an implementation of -msave-restore for RISC-V.

Differential Revision: https://reviews.llvm.org/D62685

llvm-svn: 364403
2019-06-26 10:35:58 +00:00
Simon Pilgrim 3845a4f849 [X86][AVX] truncateVectorWithPACK - avoid bitcasted shuffles
truncateVectorWithPACK is often used in conjunction with ComputeNumSignBits which struggles when peeking through bitcasts.

This fix tries to avoid bitcast(shuffle(bitcast())) patterns in the 256-bit 64-bit sublane shuffles so we can still see through at least until lowering when the shuffles will need to be bitcasted to widen the shuffle type.

llvm-svn: 364401
2019-06-26 09:50:11 +00:00
Florian Hahn 4c11b5268c [LoopUnroll] Add support for loops with exiting headers and uncond latches.
This patch generalizes the UnrollLoop utility to support loops that exit
from the header instead of the latch. Usually, LoopRotate would take care
of must of those cases, but in some cases (e.g. -Oz), LoopRotate does
not kick in.

Codesize impact looks relatively neutral on ARM64 with -Oz + LTO.

Program                                         master     patch     diff
 External/S.../CFP2006/447.dealII/447.dealII   629060.00  627676.00  -0.2%
 External/SPEC/CINT2000/176.gcc/176.gcc        1245916.00 1244932.00 -0.1%
 MultiSourc...Prolangs-C/simulator/simulator   86100.00   86156.00    0.1%
 MultiSourc...arks/Rodinia/backprop/backprop   66212.00   66252.00    0.1%
 MultiSourc...chmarks/Prolangs-C++/life/life   67276.00   67312.00    0.1%
 MultiSourc...s/Prolangs-C/compiler/compiler   69824.00   69788.00   -0.1%
 MultiSourc...Prolangs-C/assembler/assembler   86672.00   86696.00    0.0%

Reviewers: efriedma, vsk, paquette

Reviewed By: paquette

Differential Revision: https://reviews.llvm.org/D61962

llvm-svn: 364398
2019-06-26 09:16:57 +00:00
Roman Lebedev 567eea44c2 [NFC][InstCombine] Add shift amount reassociation tests (PR42391)
https://bugs.llvm.org/show_bug.cgi?id=42391
https://rise4fun.com/Alive/9E2

llvm-svn: 364393
2019-06-26 08:17:05 +00:00
Clement Courbet be98e0ab78 [ExpandMemCmp] Honor prefer-vector-width.
Reviewers: gchatelet, echristo, spatel, atdt

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63769

llvm-svn: 364384
2019-06-26 07:06:49 +00:00
QingShan Zhang e0e7d4c366 Teach the DAGCombine to fold this pattern(c1 and c2 is constant).
// fold (sext (select cond, c1, c2)) -> (select cond, sext c1, sext c2)
// fold (zext (select cond, c1, c2)) -> (select cond, zext c1, zext c2)
// fold (aext (select cond, c1, c2)) -> (select cond, sext c1, sext c2)
Sign extend the operands if it is any_extend, to keep the signess of the operands that, the other combine rule would apply. The any_extend is handled as zero extend for constants. i.e.

t1: i8 = select t0, Constant:i8<-1>, Constant:i8<0>
t2: i64 = any_extend t1
 -->
t3: i64 = select t0, Constant:i64<-1>, Constant:i64<0>
 -->
t4: i64 = sign_extend_inreg t3

Differential Revision: https://reviews.llvm.org/D63318

llvm-svn: 364382
2019-06-26 05:12:53 +00:00
Nemanja Ivanovic 4c64c62b9a [NFC] Fix buildbot breaks due to r364375
For some reason, the update_llc_checks.py script produces checks for
empty lines which cause failures. Corrected that to check for actual
text produced by llc.

llvm-svn: 364377
2019-06-26 02:46:03 +00:00
Nemanja Ivanovic 69822ae106 [PowerPC][NFC] Add a TOC save test case prior to posting a related patch
An upcoming patch will modify the behaviour with respect to saving the TOC
in functions with indirect calls.
Adding a test case so the patch will show the difference in codegen.

llvm-svn: 364375
2019-06-26 02:01:11 +00:00
Nemanja Ivanovic 8265e8ff36 [PowerPC] Mark FCOPYSIGN legal for FP vectors
This was just an omission in the back end. We have had the instructions for both
single and double precision for a few HW generations, but never got around to
legalizing these.

Differential revision: https://reviews.llvm.org/D63634

llvm-svn: 364373
2019-06-26 01:48:57 +00:00
Saleem Abdulrasool 06036dbc6e MC: correct the emission of weak aliases in COFF
The weak alias should have the characteristics set to
`IMAGE_EXTERN_WEAK_SEARCH_ALIAS` to indicate that the weak external here
is a symbol alias and that the symbol is aliased to a locally defined
symbol.  We were previously setting the characteristics to
`IMAGE_EXTERN_WEAK_SEARCH_LIBRARY` which indicates that the symbol
should be looked for in the libraries.

llvm-svn: 364370
2019-06-26 01:09:52 +00:00
Erich Keane ad28befcf4 Teach TableGen Intrin Emitter to handle LLVMPointerType<llvm_any_ty>
r363233 rewrote a bunch of the Intrin Emitter code, however the new
function to update the arg codes did not properly consider a pointer to
an any.  This patch adds that logic.

Differential Revision: https://reviews.llvm.org/D63507

llvm-svn: 364364
2019-06-26 00:08:22 +00:00
Jinsong Ji fee855b5bc [MachinePipeliner] Fix risky iterator usage R++, --R
When we calculate MII, we use two loops, one with iterator R++ to
check whether we can reserve the resource, then --R to move back
the iterator to do reservation.

This is risky, as R++, --R may not point to the same element at all.
The can cause wrong MII.

Differential Revision: https://reviews.llvm.org/D63536

llvm-svn: 364353
2019-06-25 21:50:56 +00:00
Jinsong Ji bc7fc3ecb6 [PowerPC][NFC]Add a test for MachinePipeliner bug
llvm-svn: 364350
2019-06-25 20:56:17 +00:00
Huihui Zhang b90cb57b63 [InstCombine] Simplify icmp ult/uge (shl %x, C2), C1 iff C1 is power of two -> icmp eq/ne (and %x, (lshr -C1, C2)), 0.
Simplify 'shl' inequality test into 'and' equality test.

This pattern happens in the middle-end while simplifying bitfield access,
Exposed in https://reviews.llvm.org/D63505

https://rise4fun.com/Alive/6uz

Reviewers: lebedev.ri, efriedma

Reviewed By: lebedev.ri

Subscribers: spatel, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63675

llvm-svn: 364348
2019-06-25 20:44:52 +00:00
Diego Novillo 688afeb884 Update phis in AMDGPUUnifyDivergentExitNodes
Original patch https://reviews.llvm.org/D63659 from
Steven Perron <stevenperron@google.com>

The pass AMDGPUUnifyDivergentExitNodes does not update the phi nodes in
the successors of blocks that is splits. This is fixed by calling
BasicBlock::splitBasicBlock to split the block instead of doing it
manually. This does extra work because a new conditional branch is
created in BB which is immediately replaced, but I think the simplicity
is worth it. It also helps make the code more future proof in case other
things need to be updated.

llvm-svn: 364342
2019-06-25 18:55:16 +00:00
Sanjay Patel fcfa056ceb [InstCombine] reduce checks for power-of-2-or-zero using ctpop
This follows up the transform from rL363956 to use the ctpop intrinsic when checking for power-of-2-or-zero.

This is matching the isPowerOf2() patterns used in PR42314:
https://bugs.llvm.org/show_bug.cgi?id=42314

But there's at least 1 instcombine follow-up needed to match the alternate form:

(v & (v - 1)) == 0;

We should have all of the backend expansions handled with:
rL364319
(x86-specific changes still needed for optimal code based on subtarget)

And the larger patterns to exclude zero as a power-of-2 are joining with this change after:
rL364153 ( D63660 )
rL364246

Differential Revision: https://reviews.llvm.org/D63777

llvm-svn: 364341
2019-06-25 18:51:44 +00:00
Philip Reames be0dedb2e1 [Peephole] Allow folding loads into instructions w/multiple uses (such as test64rr)
Peephole opt has a one use limitation which appears to be accidental. The function being used was incorrectly documented as returning whether the def had one *user*, but instead returned true only when there was one *use*. Add a corresponding hasOneNonDbgUser helper, and adjust peephole-opt to use the appropriate one.

All of the actual folding code handles multiple uses within a single instruction. That codepath is well exercised through instruction selection.

Differential Revision: https://reviews.llvm.org/D63656

llvm-svn: 364336
2019-06-25 17:29:18 +00:00
Craig Topper 14ea14ae85 [X86] Add a DAG combine to turn vzmovl+load into vzload if the load isn't volatile. Remove isel patterns for vzmovl+load
We currently have some isel patterns for treating vzmovl+load the same as vzload, but that shrinks the load which we shouldn't do if the load is volatile.

Rather than adding isel checks for volatile. This patch removes the patterns and teachs DAG combine to merge them into vzload when its legal to do so.

Differential Revision: https://reviews.llvm.org/D63665

llvm-svn: 364333
2019-06-25 17:08:26 +00:00
Simon Tatham e8de8ba6a6 [ARM] Support inline assembler constraints for MVE.
"To" selects an odd-numbered GPR, and "Te" an even one. There are some
8.1-M instructions that have one too few bits in their register fields
and require registers of particular parity, without necessarily using
a consecutive even/odd pair.

Also, the constraint letter "t" should select an MVE q-register, when
MVE is present. This didn't need any source changes, but some extra
tests have been added.

Reviewers: dmgreen, samparker, SjoerdMeijer

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

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D60709

llvm-svn: 364331
2019-06-25 16:49:32 +00:00
Simon Tatham a4b415a683 [ARM] Code-generation infrastructure for MVE.
This provides the low-level support to start using MVE vector types in
LLVM IR, loading and storing them, passing them to __asm__ statements
containing hand-written MVE vector instructions, and *if* you have the
hard-float ABI turned on, using them as function parameters.

(In the soft-float ABI, vector types are passed in integer registers,
and combining all those 32-bit integers into a q-reg requires support
for selection DAG nodes like insert_vector_elt and build_vector which
aren't implemented yet for MVE. In fact I've also had to add
`arm_aapcs_vfpcc` to a couple of existing tests to avoid that
problem.)

Specifically, this commit adds support for:

 * spills, reloads and register moves for MVE vector registers

 * ditto for the VPT predication mask that lives in VPR.P0

 * make all the MVE vector types legal in ISel, and provide selection
   DAG patterns for BITCAST, LOAD and STORE

 * make loads and stores of scalar FP types conditional on
   `hasFPRegs()` rather than `hasVFP2Base()`. As a result a few
   existing tests needed their llc command lines updating to use
   `-mattr=-fpregs` as their method of turning off all hardware FP
   support.

Reviewers: dmgreen, samparker, SjoerdMeijer

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60708

llvm-svn: 364329
2019-06-25 16:48:46 +00:00
Simon Pilgrim 9762b26032 [DAGCombine] combineRepeatedFPDivisors - recognize -1.0 / X as a reciprocal
Fixes issue identified by @nemanjai (Nemanja Ivanovic) in D62963 / rL363040 - infinite loop due to GetNegatedExpression fighting combineRepeatedFPDivisors resulting in fneg(fdiv(x,splat)) -> fneg(fmul(x,1.0/splat)) -> fmul(x,-1.0/splat) -> fmul(x,(-1.0 * 1.0)/splat) ......

llvm-svn: 364326
2019-06-25 16:00:16 +00:00
Fangrui Song 96a192ea53 [PPC32] Support PLT calls for -msecure-plt -fpic
Summary:
In Secure PLT ABI, -fpic is similar to -fPIC. The differences are that:

* -fpic stores the address of _GLOBAL_OFFSET_TABLE_ in r30, while -fPIC stores .got2+0x8000.
* -fpic uses an addend of 0 for R_PPC_PLTREL24, while -fPIC uses 0x8000.

Reviewers: hfinkel, jhibbits, joerg, nemanjai, spetrovic

Reviewed By: jhibbits

Subscribers: adalava, kbarton, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63563

llvm-svn: 364324
2019-06-25 15:56:32 +00:00
Sam Parker bcf0eb7a64 [ARM] Fix for DLS/LE CodeGen
The expensive buildbots highlighted the mir tests were broken, which
I've now updated and added --verify-machineinstrs to them. This also
uncovered a couple of bugs in the backend pass, so these have also
been fixed.

llvm-svn: 364323
2019-06-25 15:11:17 +00:00
Simon Pilgrim e98f8cf78f [SLPVectorizer] Precommit of supernode.ll test for D63661
This is a pre-commit of the tests introduced by the SuperNode SLP patch D63661.

Committed on behalf of @vporpo (Vasileios Porpodas)

Differential Revision: https://reviews.llvm.org/D63664

llvm-svn: 364320
2019-06-25 14:58:20 +00:00
Sanjay Patel 685c5cbc65 [SDAG] expand ctpop != 1
Change the generic ctpop expansion to more efficiently handle a
check for not-a-power-of-two value:
(ctpop x) != 1 --> (x == 0) || ((x & x-1) != 0)

This is the inverted predicate sibling pattern that was added with:
D63004

This should have been done before I changed IR canonicalization to
favor this form with:
rL364246
...so if this requires revert/changing, the earlier commit may also
need to modified.

llvm-svn: 364319
2019-06-25 14:46:52 +00:00
Matt Arsenault f4e51dd2cd AMDGPU/GlobalISel: Fix broken test
llvm-svn: 364316
2019-06-25 13:57:53 +00:00
Sanjay Patel 0baacea2c7 [AArch64][x86] add tests for ctpop != 1; NFC
This is the inverted predicate pattern for D63004.

llvm-svn: 364314
2019-06-25 13:37:16 +00:00
Simon Pilgrim 1a18bb6f25 [TargetLowering] SimplifyDemandedBits - add ANY_EXTEND_VECTOR_INREG support
Add 'lowest' demanded elt -> bitcast fold to all *_EXTEND_VECTOR_INREG cases.

Reapplies rL363856.

llvm-svn: 364311
2019-06-25 13:25:57 +00:00
Matt Arsenault dcd8b72e1a AMDGPU/GlobalISel: Fix duplicated test
Somehow ended up with copies of the same tests in AMDGPU and
AMDGPU/GlobalISel

llvm-svn: 364309
2019-06-25 13:23:08 +00:00
Matt Arsenault d7ffa2a948 AMDGPU: Select G_SEXT/G_ZEXT/G_ANYEXT
llvm-svn: 364308
2019-06-25 13:18:11 +00:00
Simon Tatham ec18f0f64c [ARM] Re-enable misspelled RUN: lines in fullfp16.s.
rL364293 committed a couple of lines that just said "// RUN llvm-mc ..."
without the all-important ':' after RUN, so those test lines weren't
actually running anything.

llvm-svn: 364305
2019-06-25 13:10:29 +00:00
Simon Pilgrim 36953ce769 [TargetLowering] SimplifyDemandedBits ZERO_EXTEND_VECTOR_INREG -> ANY_EXTEND_VECTOR_INREG
Simplify ZERO_EXTEND_VECTOR_INREG if the extended bits are not required.

Matches what we already do for ZERO_EXTEND.

Reapplies rL363850 but now with legality checks added at rL364290

llvm-svn: 364303
2019-06-25 12:57:43 +00:00
Simon Pilgrim 42f44b387e Fix frame.s test dir-separator checks
Handle / and \ separators

llvm-svn: 364301
2019-06-25 12:35:38 +00:00
Simon Pilgrim 69fc111184 [TargetLowering] SimplifyDemandedBits SIGN_EXTEND_VECTOR_INREG -> ANY/ZERO_EXTEND_VECTOR_INREG
Simplify SIGN_EXTEND_VECTOR_INREG if the extended bits are not required/known zero.

Matches what we already do for SIGN_EXTEND.

Reapplies rL363802 but now with legality checks added at rL364290

llvm-svn: 364299
2019-06-25 12:19:12 +00:00
Sjoerd Meijer 74ec25a197 [ARM] MVE VPT Blocks
A minor iteration on the MVE VPT Block pass to enable more efficient VPT Block
code generation: consecutive VPT predicated statements, predicated on the same
condition, will be placed within the same VPT Block. This essentially is also
an exercise to write some more tests for the next step, which should be more
generic also merging instructions when they are not consecutive.

Differential Revision: https://reviews.llvm.org/D63711

llvm-svn: 364298
2019-06-25 12:04:31 +00:00
Nicolai Haehnle 2710171a15 AMDGPU: Write LDS objects out as global symbols in code generation
Summary:
The symbols use the processor-specific SHN_AMDGPU_LDS section index
introduced with a previous change. The linker is then expected to resolve
relocations, which are also emitted.

Initially disabled for HSA and PAL environments until they have caught up
in terms of linker and runtime loader.

Some notes:

- The llvm.amdgcn.groupstaticsize intrinsics can no longer be lowered
  to a constant at compile times, which means some tests can no longer
  be applied.

  The current "solution" is a terrible hack, but the intrinsic isn't
  used by Mesa, so we can keep it for now.

- We no longer know the full LDS size per kernel at compile time, which
  means that we can no longer generate a relevant error message at
  compile time. It would be possible to add a check for the size of
  individual variables, but ultimately the linker will have to perform
  the final check.

Change-Id: If66dbf33fccfbf3609aefefa2558ac0850d42275

Reviewers: arsenm, rampitec, t-tye, b-sumner, jsjodin

Subscribers: qcolombet, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61494

llvm-svn: 364297
2019-06-25 11:52:30 +00:00
Nicolai Haehnle 08e8cb5760 AMDGPU/MC: Add .amdgpu_lds directive
Summary:
The directive defines a symbol as an group/local memory (LDS) symbol.
LDS symbols behave similar to common symbols for the purposes of ELF,
using the processor-specific SHN_AMDGPU_LDS as section index.

It is the linker and/or runtime loader's job to "instantiate" LDS symbols
and resolve relocations that reference them.

It is not possible to initialize LDS memory (not even zero-initialize
as for .bss).

We want to be able to link together objects -- starting with relocatable
objects, but possible expanding to shared objects in the future -- that
access LDS memory in a flexible way.

LDS memory is in an address space that is entirely separate from the
address space that contains the program image (code and normal data),
so having program segments for it doesn't really make sense.

Furthermore, we want to be able to compile multiple kernels in a
compilation unit which have disjoint use of LDS memory. In that case,
we may want to place LDS symbols differently for different kernels
to save memory (LDS memory is very limited and physically private to
each kernel invocation), so we can't simply place LDS symbols in a
.lds section.

Hence this solution where LDS symbols always stay undefined.

Change-Id: I08cbc37a7c0c32f53f7b6123aa0afc91dbc1748f

Reviewers: arsenm, rampitec, t-tye, b-sumner, jsjodin

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61493

llvm-svn: 364296
2019-06-25 11:51:35 +00:00
Simon Tatham 4cf18c2849 [ARM] Explicit lowering of half <-> double conversions.
If an FP_EXTEND or FP_ROUND isel dag node converts directly between
f16 and f32 when the target CPU has no instruction to do it in one go,
it has to be done in two steps instead, going via f32.

Previously, this was done implicitly, because all such CPUs had the
storage-only implementation of f16 (i.e. the only thing you can do
with one at all is to convert it to/from f32). So isel would legalize
the f16 into an f32 as soon as it saw it, by inserting an fp16_to_fp
node (or vice versa), and then the fp_extend would already be f32->f64
rather than f16->f64.

But that technique can't support a target CPU which has full f16
support but _not_ f64, such as some variants of Arm v8.1-M. So now we
provide custom lowering for FP_EXTEND and FP_ROUND, which checks
support for f16 and f64 and decides on the best thing to do given the
combination of flags it gets back.

Reviewers: dmgreen, samparker, SjoerdMeijer

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60692

llvm-svn: 364294
2019-06-25 11:24:50 +00:00
Simon Tatham d9654723ad [ARM] Extra MVE-related testing.
This adds some extra RUN lines to existing test files, to check that
things that worked in previous architecture versions haven't
accidentally stopped working in 8.1-M. Also we add some new tests: a
test of scalar floating point instructions that could be easily
confused with the similar-looking vector ones at assembly time, a test
of basic load/store/move access to the FP registers (which has to work
even in integer-only MVE); and one final check of the really obvious
case where turning off MVE should make sure MVE instructions really
are rejected.

Reviewers: dmgreen, samparker, SjoerdMeijer, t.p.northover

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62682

llvm-svn: 364293
2019-06-25 11:24:42 +00:00