Commit Graph

81 Commits

Author SHA1 Message Date
Andrew Trick 03b22e39be The Cortex-A9 machine model is incomplete. Mark it as such.
Many vector operations never had itineraries. Since the new machine
model was a mapping from existing itinerary classes, we don't have a
model for these. We still want to migrate A9 even though no one has
invested in a complete model, so mark it incomplete to avoid the
scheduler asserting.

llvm-svn: 198123
2013-12-28 21:57:00 +00:00
Andrew Trick 880e573d98 MI-Sched: handle latency of in-order operations with the new machine model.
The per-operand machine model allows the target to define "unbuffered"
processor resources. This change is a quick, cheap way to model stalls
caused by the latency of operations that use such resources. This only
applies when the processor's micro-op buffer size is non-zero
(Out-of-Order). We can't precisely model in-order stalls during
out-of-order execution, but this is an easy and effective
heuristic. It benefits cortex-a9 scheduling when using the new
machine model, which is not yet on by default.

MI-Sched for armv7 was evaluated on Swift (and only not enabled because
of a performance bug related to predication). However, we never
evaluated Cortex-A9 performance on MI-Sched in its current form. This
change adds MI-Sched functionality to reach performance goals on
A9. The only remaining change is to allow MI-Sched to run as a PostRA
pass.

I evaluated performance using a set of options to estimate the performance impact once MI sched is default on armv7:
-mcpu=cortex-a9 -disable-post-ra -misched-bench -scheditins=false

For a simple saxpy loop I see a 1.7x speedup. Here are the llvm-testsuite results:
(min run time over 2 runs, filtering tiny changes)

Speedups:
| Benchmarks/BenchmarkGame/recursive         |  52.39% |
| Benchmarks/VersaBench/beamformer           |  20.80% |
| Benchmarks/Misc/pi                         |  19.97% |
| Benchmarks/Misc/mandel-2                   |  19.95% |
| SPEC/CFP2000/188.ammp                      |  18.72% |
| Benchmarks/McCat/08-main/main              |  18.58% |
| Benchmarks/Misc-C++/Large/sphereflake      |  18.46% |
| Benchmarks/Olden/power                     |  17.11% |
| Benchmarks/Misc-C++/mandel-text            |  16.47% |
| Benchmarks/Misc/oourafft                   |  15.94% |
| Benchmarks/Misc/flops-7                    |  14.99% |
| Benchmarks/FreeBench/distray               |  14.26% |
| SPEC/CFP2006/470.lbm                       |  14.00% |
| mediabench/mpeg2/mpeg2dec/mpeg2decode      |  12.28% |
| Benchmarks/SmallPT/smallpt                 |  10.36% |
| Benchmarks/Misc-C++/Large/ray              |   8.97% |
| Benchmarks/Misc/fp-convert                 |   8.75% |
| Benchmarks/Olden/perimeter                 |   7.10% |
| Benchmarks/Bullet/bullet                   |   7.03% |
| Benchmarks/Misc/mandel                     |   6.75% |
| Benchmarks/Olden/voronoi                   |   6.26% |
| Benchmarks/Misc/flops-8                    |   5.77% |
| Benchmarks/Misc/matmul_f64_4x4             |   5.19% |
| Benchmarks/MiBench/security-rijndael       |   5.15% |
| Benchmarks/Misc/flops-6                    |   5.10% |
| Benchmarks/Olden/tsp                       |   4.46% |
| Benchmarks/MiBench/consumer-lame           |   4.28% |
| Benchmarks/Misc/flops-5                    |   4.27% |
| Benchmarks/mafft/pairlocalalign            |   4.19% |
| Benchmarks/Misc/himenobmtxpa               |   4.07% |
| Benchmarks/Misc/lowercase                  |   4.06% |
| SPEC/CFP2006/433.milc                      |   3.99% |
| Benchmarks/tramp3d-v4                      |   3.79% |
| Benchmarks/FreeBench/pifft                 |   3.66% |
| Benchmarks/Ptrdist/ks                      |   3.21% |
| Benchmarks/Adobe-C++/loop_unroll           |   3.12% |
| SPEC/CINT2000/175.vpr                      |   3.12% |
| Benchmarks/nbench                          |   2.98% |
| SPEC/CFP2000/183.equake                    |   2.91% |
| Benchmarks/Misc/perlin                     |   2.85% |
| Benchmarks/Misc/flops-1                    |   2.82% |
| Benchmarks/Misc-C++-EH/spirit              |   2.80% |
| Benchmarks/Misc/flops-2                    |   2.77% |
| Benchmarks/NPB-serial/is                   |   2.42% |
| Benchmarks/ASC_Sequoia/CrystalMk           |   2.33% |
| Benchmarks/BenchmarkGame/n-body            |   2.28% |
| Benchmarks/SciMark2-C/scimark2             |   2.27% |
| Benchmarks/Olden/bh                        |   2.03% |
| skidmarks10/skidmarks                      |   1.81% |
| Benchmarks/Misc/flops                      |   1.72% |

Slowdowns:
| Benchmarks/llubenchmark/llu                | -14.14% |
| Benchmarks/Polybench/stencils/seidel-2d    |  -5.67% |
| Benchmarks/Adobe-C++/functionobjects       |  -5.25% |
| Benchmarks/Misc-C++/oopack_v1p8            |  -5.00% |
| Benchmarks/Shootout/hash                   |  -2.35% |
| Benchmarks/Prolangs-C++/ocean              |  -2.01% |
| Benchmarks/Polybench/medley/floyd-warshall |  -1.98% |
| Polybench/linear-algebra/kernels/3mm       |  -1.95% |
| Benchmarks/McCat/09-vor/vor                |  -1.68% |

llvm-svn: 196516
2013-12-05 17:55:58 +00:00
Andrew Trick ff199a4b8e Fix the A9 machine model. VTRN writes two registers.
llvm-svn: 196514
2013-12-05 17:55:49 +00:00
Alp Toker f907b891da Correct word hyphenations
This patch tries to avoid unrelated changes other than fixing a few
hyphen-related ambiguities and contractions in nearby lines.

llvm-svn: 196471
2013-12-05 05:44:44 +00:00
Silviu Baranga 5cba070ce2 Fix scheduling for vldm/vstm instructions that load/store more than 32 bytes on Cortex-A9. This also makes the existing code more compact.
llvm-svn: 189958
2013-09-04 17:05:18 +00:00
Andrew Trick 18dc3da855 Update machine models. Specify buffer sizes for OOO processors.
llvm-svn: 184033
2013-06-15 04:50:02 +00:00
Andrew Trick de2109eb4c Machine Model: Add MicroOpBufferSize and resource BufferSize.
Replace the ill-defined MinLatency and ILPWindow properties with
with straightforward buffer sizes:
MCSchedMode::MicroOpBufferSize
MCProcResourceDesc::BufferSize

These can be used to more precisely model instruction execution if desired.

Disabled some misched tests temporarily. They'll be reenabled in a few commits.

llvm-svn: 184032
2013-06-15 04:49:57 +00:00
Arnold Schwaighofer eac54473dd ARM sched model: Add integer VFP/SIMD instructions on Swift
Reapply 183269.

llvm-svn: 183441
2013-06-06 20:26:18 +00:00
Arnold Schwaighofer 57142859e1 ARM sched model: Cortex A9 - More InstRW sched resources
Add more InstRW mappings.

Reapply 183266.

llvm-svn: 183435
2013-06-06 19:30:21 +00:00
Arnold Schwaighofer 2773f1deb4 ARM sched model: Add divsion, loads, branches, vfp cvt
Add some generic SchedWrites and assign resources for Swift and Cortex A9.

Reapply of r183257. (Removed empty InstRW for division on swift)

llvm-svn: 183319
2013-06-05 16:06:11 +00:00
Arnold Schwaighofer 2a70c69d31 Revert series of sched model patches until I figure out what is going on.
llvm-svn: 183273
2013-06-04 22:35:17 +00:00
Arnold Schwaighofer be3a06c85f ARM sched model: Cortex A9 - More InstRW sched resources
Add more InstRW mappings.

llvm-svn: 183266
2013-06-04 22:16:00 +00:00
Arnold Schwaighofer d5b9794a53 ARM sched model: Add divsion, loads, branches, vfp cvt
Add some generic SchedWrites and assign resources for Swift and Cortex A9.

llvm-svn: 183257
2013-06-04 22:15:46 +00:00
Arnold Schwaighofer fb6b9f48d0 ARM scheduler model: Add scheduler info to more instructions and resource
descriptions for compares

llvm-svn: 178844
2013-04-05 05:01:06 +00:00
Arnold Schwaighofer 6793aebb84 ARM Scheduler Model: Add resources instructions, map resources in subtargets
Reapply r177968:
After commit 178074 we can now have undefined scheduler variants.

Move the CortexA9 resources into the CortexA9 SchedModel namespace. Define
resource mappings under the CortexA9 SchedModel. Define resources and mappings
for the SwiftModel.

Incooperate Andrew's feedback.

llvm-svn: 178460
2013-04-01 13:07:05 +00:00
Arnold Schwaighofer 414ef565bb Revert ARM Scheduler Model: Add resources instructions, map resources
This reverts commit r177968. It is causing failures in a local build bot.

"fatal error: error in backend: Expected a variant SchedClass"

Original commit message:
Move the CortexA9 resources into the CortexA9 SchedModel namespace. Define
resource mappings under the CortexA9 SchedModel. Define resources and mappings
for the SwiftModel.

llvm-svn: 178028
2013-03-26 15:14:04 +00:00
Arnold Schwaighofer ce6392611b ARM Scheduler Model: Add resources instructions, map resources in subtargets
Move the CortexA9 resources into the CortexA9 SchedModel namespace. Define
resource mappings under the CortexA9 SchedModel. Define resources and mappings
for the SwiftModel.

llvm-svn: 177968
2013-03-26 02:01:42 +00:00
Andrew Trick 9f0b95f260 MIsched: add an ILP window property to machine model.
This was an experimental option, but needs to be defined
per-target. e.g. PPC A2 needs to aggressively hide latency.

I converted some in-order scheduling tests to A2. Hal is working on
more test cases.

llvm-svn: 171946
2013-01-09 03:36:49 +00:00
Andrew Trick 99cc7f6a3b Cortex-A9 latency fixes (w/ -schedmodel only).
Quick review against the manual revealed a few obvious mistakes.

llvm-svn: 164361
2012-09-21 05:06:40 +00:00
Andrew Trick 985dc0dd64 Cortex-A9 instruction-level scheduling machine model.
This models the A9 processor at the level of instruction operands, as
opposed to the itinerary, which models each operation at the level of
pipeline stages.

The two primary motivations are:

1) Allow MachineScheduler to model A9 as an out-of-order processor. It
can now distinguish between hazards that force interlocking vs.
buffered resources.

2) Reduce long-term maintenance by allowing the itinerary and target
hooks to eventually be removed. Note that almost all of the complexity
in the new model exists to model instruction variants, which the
itinerary cannot handle. Instead the scheduler previously relied on
processor-specific target hooks which are incomplete and buggy.

llvm-svn: 163921
2012-09-14 18:31:58 +00:00
Andrew Trick 352abc19a5 Added MispredictPenalty to SchedMachineModel.
This replaces an existing subtarget hook on ARM and allows standard
CodeGen passes to potentially use the property.

llvm-svn: 161471
2012-08-08 02:44:16 +00:00
Andrew Trick 87255e340e I'm introducing a new machine model to simultaneously allow simple
subtarget CPU descriptions and support new features of
MachineScheduler.

MachineModel has three categories of data:
1) Basic properties for coarse grained instruction cost model.
2) Scheduler Read/Write resources for simple per-opcode and operand cost model (TBD).
3) Instruction itineraties for detailed per-cycle reservation tables.

These will all live side-by-side. Any subtarget can use any
combination of them. Instruction itineraries will not change in the
near term. In the long run, I expect them to only be relevant for
in-order VLIW machines that have complex contraints and require a
precise scheduling/bundling model. Once itineraries are only actively
used by VLIW-ish targets, they could be replaced by something more
appropriate for those targets.

This tablegen backend rewrite sets things up for introducing
MachineModel type #2: per opcode/operand cost model.

llvm-svn: 159891
2012-07-07 04:00:00 +00:00
Andrew Trick f161e391f8 Reapply "Make NumMicroOps a variable in the subtarget's instruction itinerary."
Reapplies r159406 with minor cleanup. The regressions appear to have been spurious.

llvm-svn: 159541
2012-07-02 18:10:42 +00:00
Andrew Trick 51a8cf77b8 Revert "Make NumMicroOps a variable in the subtarget's instruction itinerary."
This reverts commit r159406. I noticed a performance regression so I'll back out for now.

llvm-svn: 159411
2012-06-29 07:10:41 +00:00
Andrew Trick 1f50152b2d Make NumMicroOps a variable in the subtarget's instruction itinerary.
The TargetInstrInfo::getNumMicroOps API does not change, but soon it
will be used by MachineScheduler. Now each subtarget can specify the
number of micro-ops per itinerary class. For ARM, this is currently
always dynamic (-1), because it is used for load/store multiple which
depends on the number of register operands.

Zero is now a valid number of micro-ops. This can be used for
nop pseudo-instructions or instructions that the hardware can squash
during dispatch.

llvm-svn: 159406
2012-06-29 03:23:18 +00:00
Andrew Trick b2680c718f ARM itinerary properties.
llvm-svn: 157980
2012-06-05 03:44:43 +00:00
Evan Cheng aca6c822e6 Fix a number of problems with ARM fused multiply add/subtract instructions.
1. The new instruction itinerary entries are not properly described.
2. The asm parser can't handle vfms and vfnms.
3. There were no assembler, disassembler test cases.
4. HasNEON2 has the wrong assembler predicate.
rdar://10139676

llvm-svn: 154456
2012-04-11 00:13:00 +00:00
Bob Wilson f33715e554 Improvements for the Cortex-A9 scheduling itineraries.
llvm-svn: 129770
2011-04-19 18:11:36 +00:00
Evan Cheng 7d6cd4902e Change A9 scheduling itineraries VLD* / VST* entries default to "aligned". That
is, it assumes addresses are 64-bit aligned (which should be the more common
case). If the alignment is found not to be aligned, then getOperandLatency()
would adjust the operand latency computation by one to compensate for it.
rdar://9294833

llvm-svn: 129742
2011-04-19 01:21:49 +00:00
Evan Cheng b8b0ad80a8 Sorry, several patches in one.
TargetInstrInfo:
Change produceSameValue() to take MachineRegisterInfo as an optional argument.
When in SSA form, targets can use it to make more aggressive equality analysis.

Machine LICM:
1. Eliminate isLoadFromConstantMemory, use MI.isInvariantLoad instead.
2. Fix a bug which prevent CSE of instructions which are not re-materializable.
3. Use improved form of produceSameValue.

ARM:
1. Teach ARM produceSameValue to look pass some PIC labels.
2. Look for operands from different loads of different constant pool entries
   which have same values.
3. Re-implement PIC GA materialization using movw + movt. Combine the pair with
   a "add pc" or "ldr [pc]" to form pseudo instructions. This makes it possible
   to re-materialize the instruction, allow machine LICM to hoist the set of
   instructions out of the loop and make it possible to CSE them. It's a bit
   hacky, but it significantly improve code quality.
4. Some minor bug fixes as well.

With the fixes, using movw + movt to materialize GAs significantly outperform the
load from constantpool method. 186.crafty and 255.vortex improved > 20%, 254.gap
and 176.gcc ~10%.

llvm-svn: 123905
2011-01-20 08:34:58 +00:00
Andrew Trick 163a24420a Fix the ARM IIC_iCMPsi itinerary and add an important assert.
llvm-svn: 122794
2011-01-04 00:32:57 +00:00
Evan Cheng 7f3e9150d0 Fix an obvious cut-n-paste error.
llvm-svn: 121307
2010-12-08 23:01:18 +00:00
Bob Wilson 431ac4ef50 Add support for NEON VLD3-dup instructions.
The encoding for alignment in VLD4-dup instructions is still a work in progress.

llvm-svn: 120356
2010-11-30 00:00:35 +00:00
Bob Wilson 77ab165afe Add support for NEON VLD3-dup instructions.
llvm-svn: 120312
2010-11-29 19:35:29 +00:00
Bob Wilson 8022367809 Fix copy-and-paste errors in VLD2-dup scheduling itineraries.
llvm-svn: 120311
2010-11-29 19:35:23 +00:00
Bob Wilson 2d790df105 Add support for NEON VLD2-dup instructions.
llvm-svn: 120236
2010-11-28 06:51:26 +00:00
Bob Wilson c92eea0175 Add NEON VLD1-dup instructions (load 1 element to all lanes).
llvm-svn: 120194
2010-11-27 06:35:16 +00:00
Bob Wilson 3a63f9d852 Fix incorrect scheduling itineraries for NEON vld1/vst1 instructions.
I added these instructions recently but I have no idea where these "1"
values in the NextCycles field came from.  As far as I can tell now,
these instruction stages are clearly intended to overlap.

llvm-svn: 120193
2010-11-27 06:35:09 +00:00
Evan Cheng 79ff5238e9 Conditional moves are slightly more expensive than moves.
llvm-svn: 118985
2010-11-13 05:14:20 +00:00
Evan Cheng 8740ee3637 Fix preload instruction isel. Only v7 supports pli, and only v7 with mp extension supports pldw. Add subtarget attribute to denote mp extension support and legalize illegal ones to nothing.
llvm-svn: 118160
2010-11-03 06:34:55 +00:00
Evan Cheng 634ab6c2b7 Modify scheduling itineraries to correct instruction latencies (not operand
latencies) of loads.

llvm-svn: 118134
2010-11-03 00:40:22 +00:00
Bob Wilson d80b29d6f7 Add NEON VST1-lane instructions. Partial fix for Radar 8599955.
llvm-svn: 118069
2010-11-02 21:18:25 +00:00
Bob Wilson dc44990c7d Add NEON VLD1-lane instructions. Partial fix for Radar 8599955.
llvm-svn: 117964
2010-11-01 22:04:05 +00:00
Evan Cheng 99cce36cf5 Fix fpscr <-> GPR latency info.
llvm-svn: 117737
2010-10-29 23:16:55 +00:00
Evan Cheng ff310737e5 Re-commit 117518 and 117519 now that ARM MC test failures are out of the way.
llvm-svn: 117531
2010-10-28 06:47:08 +00:00
Evan Cheng e2c211c1b9 Revert 117518 and 117519 for now. They changed scheduling and cause MC tests to fail. Ugh.
llvm-svn: 117520
2010-10-28 02:00:25 +00:00
Evan Cheng ff1c862f8e - Assign load / store with shifter op address modes the right itinerary classes.
- For now, loads of [r, r] addressing mode is the same as the
  [r, r lsl/lsr/asr #] variants. ARMBaseInstrInfo::getOperandLatency() should
  identify the former case and reduce the output latency by 1.
- Also identify [r, r << 2] case. This special form of shifter addressing mode
  is "free".

llvm-svn: 117519
2010-10-28 01:49:06 +00:00
Andrew Trick f4ebec03e0 putback r116983 and fix simple-fp-encoding.ll tests
llvm-svn: 116992
2010-10-21 03:40:16 +00:00
Owen Anderson 9e00f27e14 Revert r116983, which is breaking all the buildbots.
llvm-svn: 116987
2010-10-21 03:11:16 +00:00
Evan Cheng 15c2ac90ec Add missing scheduling itineraries for transfers between core registers and VFP registers.
llvm-svn: 116983
2010-10-21 01:12:00 +00:00