Commit Graph

191 Commits

Author SHA1 Message Date
Alp Toker d8d510af92 Move remaining LLVM_ENABLE_DUMP conditionals out of the headers
This macro is sometimes defined manually but isn't (and doesn't need to be) in
llvm-config.h so shouldn't appear in the headers, likewise NDEBUG.

Instead switch them over to LLVM_DUMP_METHOD on the definitions.

llvm-svn: 212130
2014-07-01 21:19:13 +00:00
Alp Toker e69170a110 Revert "Introduce a string_ostream string builder facilty"
Temporarily back out commits r211749, r211752 and r211754.

llvm-svn: 211814
2014-06-26 22:52:05 +00:00
Alp Toker 614717388c Introduce a string_ostream string builder facilty
string_ostream is a safe and efficient string builder that combines opaque
stack storage with a built-in ostream interface.

small_string_ostream<bytes> additionally permits an explicit stack storage size
other than the default 128 bytes to be provided. Beyond that, storage is
transferred to the heap.

This convenient class can be used in most places an
std::string+raw_string_ostream pair or SmallString<>+raw_svector_ostream pair
would previously have been used, in order to guarantee consistent access
without byte truncation.

The patch also converts much of LLVM to use the new facility. These changes
include several probable bug fixes for truncated output, a programming error
that's no longer possible with the new interface.

llvm-svn: 211749
2014-06-26 00:00:48 +00:00
Alp Toker beaca19c7c Fix typos
llvm-svn: 208839
2014-05-15 01:52:21 +00:00
Chandler Carruth 1b9dde087e [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE
define below all header includes in the lib/CodeGen/... tree. While the
current modules implementation doesn't check for this kind of ODR
violation yet, it is likely to grow support for it in the future. It
also removes one layer of macro pollution across all the included
headers.

Other sub-trees will follow.

llvm-svn: 206837
2014-04-22 02:02:50 +00:00
Hal Finkel bae796f0dc Remove seemingly-unneeded artificial dependency
The rationale for this artificial dependency seems to have been lost to the
ravages of time, it is covered by no regression tests, and has no impact on
test-suite performance numbers on either x86 or PPC.

For the test suite, on both x86 and PPC, I ran the test suite 10 times (both as
a baseline and with this change), and found no statistically-significant
changes.  For PPC, I used a P7 box. For x86, I used an Intel Xeon E5430. Both
with -O3 -mcpu=native.

This was discussed on-list back in January, but I've not had a chance to run
the performance tests until today.

llvm-svn: 206795
2014-04-21 21:30:25 +00:00
Andrew Trick 1766f93b35 Better comments to explain buffered/unbuffered processor resources.
llvm-svn: 206625
2014-04-18 17:35:08 +00:00
Nick Lewycky aad475b324 Break PseudoSourceValue out of the Value hierarchy. It is now the root of its own tree containing FixedStackPseudoSourceValue (which you can use isa/dyn_cast on) and MipsCallEntry (which you can't). Anything that needs to use either a PseudoSourceValue* and Value* is strongly encouraged to use a MachinePointerInfo instead.
llvm-svn: 206255
2014-04-15 07:22:52 +00:00
Craig Topper c0196b1b40 [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr.
llvm-svn: 206142
2014-04-14 00:51:57 +00:00
Hal Finkel 3b48d08f54 Reenable use of TBAA during CodeGen
We had disabled use of TBAA during CodeGen (even when otherwise using AA)
because the ptrtoint/inttoptr used by CGP for address sinking caused BasicAA to
miss basic type punning that it should catch (and, thus, we'd fail to override
TBAA when we should).

However, when AA is in use during CodeGen, CGP now uses normal GEPs and
bitcasts, instead of ptrtoint/inttoptr, when doing address sinking. As a
result, BasicAA should be able to make us do the right thing in the face of
type-punning, and it seems safe to enable use of TBAA again. self-hosting seems
fine on PPC64/Linux on the P7, with TBAA enabled and -misched=shuffle.

Note: We still don't update TBAA when merging stack slots, although because
BasicAA should now catch all such cases, this is no longer a blocking issue.
Nevertheless, I plan to commit code to deal with this properly in the near
future.

llvm-svn: 206093
2014-04-12 01:26:00 +00:00
Rafael Espindola b1f25f1b93 Replace PROLOG_LABEL with a new CFI_INSTRUCTION.
The old system was fairly convoluted:
* A temporary label was created.
* A single PROLOG_LABEL was created with it.
* A few MCCFIInstructions were created with the same label.

The semantics were that the cfi instructions were mapped to the PROLOG_LABEL
via the temporary label. The output position was that of the PROLOG_LABEL.
The temporary label itself was used only for doing the mapping.

The new CFI_INSTRUCTION has a 1:1 mapping to MCCFIInstructions and points to
one by holding an index into the CFI instructions of this function.

I did consider removing MMI.getFrameInstructions completelly and having
CFI_INSTRUCTION own a MCCFIInstruction, but MCCFIInstructions have non
trivial constructors and destructors and are somewhat big, so the this setup
is probably better.

The net result is that we don't create temporary labels that are never used.

llvm-svn: 203204
2014-03-07 06:08:31 +00:00
Benjamin Kramer b6d0bd48bd [C++11] Replace llvm::next and llvm::prior with std::next and std::prev.
Remove the old functions.

llvm-svn: 202636
2014-03-02 12:27:27 +00:00
Nick Lewycky 1ce017e8cb Indent this continued line.
llvm-svn: 202096
2014-02-25 00:43:21 +00:00
Nick Lewycky c4a9f8a019 Fix change in behaviour accidentally introduced in r201754.
llvm-svn: 201758
2014-02-20 06:35:31 +00:00
Nick Lewycky b9e44d6bcf Simplify the implementation of getUnderlyingObjectsForInstr, without intending to change the semantics at all.
llvm-svn: 201754
2014-02-20 05:06:26 +00:00
Hal Finkel dbebb52a2f Disable the use of TBAA when using AA in CodeGen
There are currently two issues, of which I currently know, that prevent TBAA
from being correctly usable in CodeGen:

  1. Stack coloring does not update TBAA when merging allocas. This is easy
     enough to fix, but is not the largest problem.

  2. CGP inserts ptrtoint/inttoptr pairs when sinking address computations.
     Because BasicAA does not handle inttoptr, we'll often miss basic type punning
     idioms that we need to catch so we don't miscompile real-world code (like LLVM).

I don't yet have a small test case for this, but this fixes self hosting a
non-asserts build of LLVM on PPC64 when using -enable-aa-sched-mi and -misched=shuffle.

llvm-svn: 200093
2014-01-25 19:24:54 +00:00
Hal Finkel a228a8187b Track multiple stores per object when using AA in ScheduleDAGInstrs
When using AA to break false chain dependencies, we need to track multiple
stores per object in ScheduleDAGInstrs. Historically, we tracked potential alias
chains at the object level, and so all loads of an object would retain
dependencies on any store to that object. With AA, however, this is not
sufficient: non-overlapping stores and loads to the same object all need to be
tested for dependencies separately, we cannot only test all loads to an object
against only the last store (see PR18497 for an explicit example).

To mitigate any unwelcome compile-time impact when not using AA, only one store
is kept in the list per object when not using AA.

This, along with a stack coloring change to come shortly, will provide a test
case, fix PR18497 (and allow LLVM to compile itself using -enable-aa-sched-mi
on x86-64).

llvm-svn: 199657
2014-01-20 14:03:02 +00:00
Hal Finkel 2150e3a743 Conservatively handle multiple MMOs in MIsNeedChainEdge
MIsNeedChainEdge, which is used by -enable-aa-sched-mi (AA in misched), had an
llvm_unreachable when -enable-aa-sched-mi is enabled and we reach an
instruction with multiple MMOs. Instead, return a conservative answer. This
allows testing -enable-aa-sched-mi on x86.

Also, this moves the check above the isUnsafeMemoryObject checks.
isUnsafeMemoryObject is currently correct only for instructions with one MMO
(as noted in the comment in isUnsafeMemoryObject):

  // We purposefully do no check for hasOneMemOperand() here
  // in hope to trigger an assert downstream in order to
  // finish implementation.

The problem with this is that, had the candidate edge passed the
"!MIa->mayStore() && !MIb->mayStore()" check, the hoped-for assert would never
happen (which could, in theory, lead to incorrect behavior if one of these
secondary MMOs was volatile, for example).

llvm-svn: 198795
2014-01-08 21:52:02 +00:00
Andrew Trick 6b104f8b9e Move the PostRA scheduler's fixupKills function for reuse.
llvm-svn: 198121
2013-12-28 21:56:55 +00:00
Andrew Trick 5a22df498e MI-Sched: Model "reserved" processor resources.
This allows a target to use MI-Sched as an in-order scheduler that
will model strict resource conflicts without defining a processor
itinerary. Instead, the target can now use the new per-operand machine
model and define in-order resources with BufferSize=0. For example,
this would allow restricting the type of operations that can be formed
into a dispatch group. (Normally NumMicroOps is sufficient to enforce
dispatch groups).

If the intent is to model latency in in-order pipeline, as opposed to
resource conflicts, then a resource with BufferSize=1 should be
defined instead.

This feature is only casually tested as there are no in-tree targets
using it yet. However, Hal will be experimenting with POWER7.

llvm-svn: 196517
2013-12-05 17:56:02 +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
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
Matthias Braun 88dd0abd2d Pass LiveQueryResult by value
This makes the API a bit more natural to use and makes it easier to make
LiveRanges implementation details private.

llvm-svn: 192394
2013-10-10 21:28:52 +00:00
Andrew Trick 310190e21f mi-sched: bypass heuristic checks when regpressure tracking is disabled.
llvm-svn: 189988
2013-09-04 21:00:02 +00:00
Andrew Trick 2bc74c2887 mi-sched: update PressureDiffs on-the-fly for liveness.
This removes all expensive pressure tracking logic from the scheduling
critical path of node comparison.

llvm-svn: 189643
2013-08-30 04:36:57 +00:00
Andrew Trick 1a8313458f mi-sched: Precompute a PressureDiff for each instruction, adjust for liveness later.
Created SUPressureDiffs array to hold the per node PDiff computed during DAG building.

Added a getUpwardPressureDelta API that will soon replace the old
one. Compute PressureDelta here from the precomputed PressureDiffs.

Updating for liveness will come next.

llvm-svn: 189640
2013-08-30 03:49:48 +00:00
Andrew Trick 483f4199f3 Comment and revise the cyclic critical path code.
This should be much more clear now. It's still disabled pending testing.

llvm-svn: 189597
2013-08-29 18:04:49 +00:00
Hal Finkel b350ffd1b1 Add useAA() to TargetSubtargetInfo
There are several optional (off-by-default) features in CodeGen that can make
use of alias analysis. These features are important for generating code for
some kinds of cores (for example the (in-order) PPC A2 core). This adds a
useAA() function to TargetSubtargetInfo to allow these features to be enabled
by default on a per-subtarget basis.

Here is the first use of this function: To control the default of the
-enable-aa-sched-mi feature.

llvm-svn: 189563
2013-08-29 03:25:05 +00:00
Andrew Trick c01b00400d Adds cyclic critical path computation and heuristics, temporarily disabled.
Estimate the cyclic critical path within a single block loop. If the
acyclic critical path is longer, then the loop will exhaust OOO
resources after some number of iterations. If lag between the acyclic
critical path and cyclic critical path is longer the the time it takes
to issue those loop iterations, then aggressively schedule for
latency.

llvm-svn: 189120
2013-08-23 17:48:43 +00:00
Andrew Trick 8dd26f002f MI Sched: record local vreg uses.
This will be used to compute the cyclic critical path and to
update precomputed per-node pressure differences.
In the longer term, it could also be used to speed up LiveInterval
update by avoiding visiting all global vreg users.

llvm-svn: 189118
2013-08-23 17:48:39 +00:00
Andrew Trick a53e101627 mi-sched: Don't call MBB.size() in initSUnits. The driver already has instr count.
This fixes a pathological compile time problem with very large blocks
and lots of scheduling boundaries.

llvm-svn: 189116
2013-08-23 17:48:33 +00:00
Craig Topper e1c1d363a5 Use SmallVectorImpl instead of SmallVector for iterators and references to avoid specifying the vector size unnecessarily.
llvm-svn: 185512
2013-07-03 05:11:49 +00:00
Benjamin Kramer fd51092719 misched: Compress pairs returned by getUnderlyingObjectsForInstr.
llvm-svn: 185266
2013-06-29 18:41:17 +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
Andrew Trick e833e1cd6e MI-Sched: schedule physreg copies.
The register allocator expects minimal physreg live ranges. Schedule
physreg copies accordingly. This is slightly tricky when they occur in
the middle of the scheduling region. For now, this is handled by
rescheduling the copy when its associated instruction is
scheduled. Eventually we may instead bundle them, but only if we can
preserve the bundles as parallel copies during regalloc.

llvm-svn: 179449
2013-04-13 06:07:40 +00:00
Sergei Larin 5e76aa9714 Equal treatment of labels and other terminators in MI DAG construction.
MI sched DAG construction allows targets to include terminators into scheduling DAG.
Extend this functionality to labels as well.

llvm-svn: 174977
2013-02-12 16:36:03 +00:00
Andrew Trick b36388a1cb ScheduleDAG: colorize the DOT graph and improve formatting.
llvm-svn: 173431
2013-01-25 07:45:25 +00:00
Andrew Trick 646eeb6675 ScheduleDAG: Added isBoundaryNode to conveniently detect a common corner case.
This fixes DAG subtree analysis at the boundary.

llvm-svn: 173427
2013-01-25 06:52:30 +00:00
Andrew Trick ffc8097c60 SchedDFS: Complete support for nested subtrees.
Maintain separate per-node and per-tree book-keeping.
Track all instructions above a DAG node including nested subtrees.
Seperately track instructions within a subtree.
Record subtree parents.

llvm-svn: 173426
2013-01-25 06:52:27 +00:00
Andrew Trick e2c3f5c982 MIsched: Improve the interface to SchedDFS analysis (subtrees).
Allow the strategy to select SchedDFS. Allow the results of SchedDFS
to affect initialization of the scheduler state.

llvm-svn: 173425
2013-01-25 06:33:57 +00:00
Andrew Trick 5b07eeb24a SchedDFS: Initial support for nested subtrees.
This is mostly refactoring, along with adding an instruction count
within the subtrees and ensuring we only look at data edges.

llvm-svn: 173420
2013-01-25 06:02:44 +00:00
Andrew Trick b52a8564ce SchedDFS: Refactor and tweak the subtree selection criteria.
For sanity, create a root when NumDataSuccs >= 4. Splitting large
subtrees will no longer be detrimental after my next checkin to handle
nested tree. A magic number of 4 is fine because single subtrees
seldom rejoin more than this. It makes subtrees easier to visualize
and heuristics more sane.

llvm-svn: 173399
2013-01-25 00:12:57 +00:00
Michael Ilseman 3e3194f4ec Introduce a new data structure, the SparseMultiSet, and changes to the MI scheduler to use it.
A SparseMultiSet adds multiset behavior to SparseSet, while retaining SparseSet's desirable properties. Essentially, SparseMultiSet provides multiset behavior by storing its dense data in doubly linked lists that are inlined into the dense vector. This allows it to provide good data locality as well as vector-like constant-time clear() and fast constant time find(), insert(), and erase(). It also allows SparseMultiSet to have a builtin recycler rather than keeping SparseSet's behavior of always swapping upon removal, which allows it to preserve more iterators. It's often a better alternative to a SparseSet of a growable container or vector-of-vector.

llvm-svn: 173064
2013-01-21 18:18:53 +00:00
Chandler Carruth 9fb823bbd4 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

llvm-svn: 171366
2013-01-02 11:36:10 +00:00
Andrew Trick ec2564818c MISched: add dependence to ExitSU to model live-out latency.
llvm-svn: 170454
2012-12-18 20:53:01 +00:00
Hal Finkel 66859ae0f6 Use GetUnderlyingObjects in misched
misched used GetUnderlyingObject in order to break false load/store
dependencies, and the -enable-aa-sched-mi feature similarly relied on
GetUnderlyingObject in order to ensure it is safe to use the aliasing analysis.
Unfortunately, GetUnderlyingObject does not recurse through phi nodes, and so
(especially due to LSR) all of these mechanisms failed for
induction-variable-dependent loads and stores inside loops.

This change replaces uses of GetUnderlyingObject with GetUnderlyingObjects
(which will recurse through phi and select instructions) in misched.

Andy reviewed, tested and simplified this patch; Thanks!

llvm-svn: 169744
2012-12-10 18:49:16 +00:00
Chandler Carruth ed0881b2a6 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

llvm-svn: 169131
2012-12-03 16:50:05 +00:00
Andrew Trick b767d1eba8 misched: Fix RegisterPressureTracker handling of DebugVals.
Assertion failed: (TopRPTracker.getPos() == RegionBegin && "bad initial Top tracker").
rdar://12790302.

llvm-svn: 169072
2012-12-01 01:22:49 +00:00
Andrew Trick d5953622ce misched: Fix the DAG builder to handle an undef operand at ExitSU.
Assertion failed: (VNI && "No value to read by operand")
rdar://12790267.

llvm-svn: 169071
2012-12-01 01:22:44 +00:00
Andrew Trick 48d392e81e misched: Analysis that partitions the DAG into subtrees.
This is a simple, cheap infrastructure for analyzing the shape of a
DAG. It recognizes uniform DAGs that take the shape of bottom-up
subtrees, such as the included matrix multiplication example. This is
useful for heuristics that balance register pressure with ILP. Two
canonical expressions of the heuristic are implemented in scheduling
modes: -misched-ilpmin and -misched-ilpmax.

llvm-svn: 168773
2012-11-28 05:13:28 +00:00