Commit Graph

63 Commits

Author SHA1 Message Date
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
2018-05-14 12:53:11 +00:00
Sanjay Patel 0d7df36c66 [TargetSchedule] shrink interface for init(); NFCI
The TargetSchedModel is always initialized using the TargetSubtargetInfo's 
MCSchedModel and TargetInstrInfo, so we don't need to extract those and 
pass 3 parameters to init().

Differential Revision: https://reviews.llvm.org/D44789

llvm-svn: 329540
2018-04-08 19:56:04 +00:00
Reid Kleckner 2aeb930a9f Revert r327721 "This patch fixes the invalid usage of OptSize in Machine Combiner."
It causes asserts when compiling Chromium on Win32 with optimizations.
We compile many things with -Os.

llvm-svn: 327733
2018-03-16 20:11:55 +00:00
Andrew V. Tischenko a0cd09d4a2 This patch fixes the invalid usage of OptSize in Machine Combiner.
Differential Revision: https://reviews.llvm.org/D43813

llvm-svn: 327721
2018-03-16 16:06:24 +00:00
Andrew V. Tischenko 083891925b The final step to close D41278 [MachineCombiner] Improve debug output (NFC).
Differential Revision: https://reviews.llvm.org/D41278

llvm-svn: 326074
2018-02-26 09:43:21 +00:00
Andrew V. Tischenko b65b078d4d (NFC)[MachineCombiner] Improve debug output.
llvm-svn: 325217
2018-02-15 07:55:02 +00:00
Alexander Ivchenko 6805004cb1 Fix unused variable warning in release mode. NFC.
llvm-svn: 324330
2018-02-06 09:53:02 +00:00
Florian Hahn c68428b5dc [MachineCombiner] Add check for optimal pattern order.
In D41587, @mssimpso discovered that the order of some patterns for
AArch64 was sub-optimal. I thought a bit about how we could avoid that
case in the future. I do not think there is a need for evaluating all
patterns for now. But this patch adds an extra (expensive) check, that
evaluates the latencies of all patterns, and ensures that the latency
saved decreases for subsequent patterns.

This catches the sub-optimal order fixed in D41587, but I am not
entirely happy with the check, as it only applies to sub-optimal
patterns seen while building with EXPENSIVE_CHECKS on. It did not
discover any other sub-optimal pattern ordering.

Reviewers: Gerolf, spatel, mssimpso

Reviewed By: Gerolf, mssimpso

Differential Revision: https://reviews.llvm.org/D41766

llvm-svn: 323873
2018-01-31 13:54:30 +00:00
Matthias Braun f1caa2833f MachineFunction: Return reference from getFunction(); NFC
The Function can never be nullptr so we can return a reference.

llvm-svn: 320884
2017-12-15 22:22:58 +00:00
Michael Zolotukhin c468b648fd Remove redundant includes from lib/CodeGen.
llvm-svn: 320619
2017-12-13 21:30:47 +00:00
Florian Hahn 001c3dd202 [MachineCombiner] Add up latencies of all instructions in new pattern.
Summary:
When calculating the RootLatency, we add up all the latencies of the
deleted instructions. But for NewRootLatency we only add the latency of
the new root instructions, ignoring the latencies of the other
instructions inserted. This leads the combiner to underestimate the cost
of patterns which add multiple instructions. This patch fixes that by
summing up the latencies of all new instructions. For NewRootNode, the
more complex getLatency function is used.

Note that we may be slightly more precise than just summing up
all latencies. For example, consider a pattern like

    r1 = INS1 ..
    r2 = INS2 ..
    r3 = INS3 r1, r2

I think in some other places, the total latency of the pattern would be
estimated as lat(INS3) + max(lat(INS1), lat(INS2)). If you consider
that worth changing, I think it would be best to do in a follow-up
patch.

Reviewers: Gerolf, sebpop, spop, fhahn

Reviewed By: fhahn

Subscribers: evandro, llvm-commits

Differential Revision: https://reviews.llvm.org/D40307

llvm-svn: 319951
2017-12-06 20:27:33 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
David Blaikie 3f833edc7c Target/TargetInstrInfo.h -> CodeGen/TargetInstrInfo.h to match layering
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.

llvm-svn: 317647
2017-11-08 01:01:31 +00:00
Simon Pilgrim 194693e996 [MC] Split out register def/use idx calls to make debugging simpler. NFCI.
llvm-svn: 316927
2017-10-30 17:24:40 +00:00
Florian Hahn e52abba277 [MachineCombiner] Fix initialisation of LastUpdate for incremental update.
Summary:
Fixes a bogus iterator resulting from the removal of a block's first instruction at the point that incremental update is enabled.

Patch by Paul Walker.

Reviewers: fhahn, Gerolf, efriedma, MatzeB

Reviewed By: fhahn

Subscribers: aemerson, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D38734

llvm-svn: 315502
2017-10-11 20:25:58 +00:00
Florian Hahn ceb4494786 Recommit [MachineCombiner] Update instruction depths incrementally for large BBs.
This version of the patch fixes an off-by-one error causing PR34596. We
do not need to use std::next(BlockIter) when calling updateDepths, as
BlockIter already points to the next element.

Original commit message:
> For large basic blocks with lots of combinable instructions, the
> MachineTraceMetrics computations in MachineCombiner can dominate the compile
> time, as computing the trace information is quadratic in the number of
> instructions in a BB and it's relevant successors/predecessors.

> In most cases, knowing the instruction depth should be enough to make
> combination decisions. As we already iterate over all instructions in a basic
> block, the instruction depth can be computed incrementally. This reduces the
> cost of machine-combine drastically in cases where lots of instructions
> are combined. The major drawback is that AFAIK, computing the critical path
> length cannot be done incrementally. Therefore we only compute
> instruction depths incrementally, for basic blocks with more
> instructions than inc_threshold. The -machine-combiner-inc-threshold
> option can be used to set the threshold and allows for easier
> experimenting and checking if using incremental updates for all basic
> blocks has any impact on the performance.
>
> Reviewers: sanjoy, Gerolf, MatzeB, efriedma, fhahn
>
> Reviewed By: fhahn
>
> Subscribers: kiranchandramohan, javed.absar, efriedma, llvm-commits
>
> Differential Revision: https://reviews.llvm.org/D36619

llvm-svn: 313751
2017-09-20 11:54:37 +00:00
Hans Wennborg 06e2a384c2 Revert r312719 "[MachineCombiner] Update instruction depths incrementally for large BBs."
This caused PR34596.

> [MachineCombiner] Update instruction depths incrementally for large BBs.
>
> Summary:
> For large basic blocks with lots of combinable instructions, the
> MachineTraceMetrics computations in MachineCombiner can dominate the compile
> time, as computing the trace information is quadratic in the number of
> instructions in a BB and it's relevant successors/predecessors.
>
> In most cases, knowing the instruction depth should be enough to make
> combination decisions. As we already iterate over all instructions in a basic
> block, the instruction depth can be computed incrementally. This reduces the
> cost of machine-combine drastically in cases where lots of instructions
> are combined. The major drawback is that AFAIK, computing the critical path
> length cannot be done incrementally. Therefore we only compute
> instruction depths incrementally, for basic blocks with more
> instructions than inc_threshold. The -machine-combiner-inc-threshold
> option can be used to set the threshold and allows for easier
> experimenting and checking if using incremental updates for all basic
> blocks has any impact on the performance.
>
> Reviewers: sanjoy, Gerolf, MatzeB, efriedma, fhahn
>
> Reviewed By: fhahn
>
> Subscribers: kiranchandramohan, javed.absar, efriedma, llvm-commits
>
> Differential Revision: https://reviews.llvm.org/D36619

llvm-svn: 313213
2017-09-13 23:23:09 +00:00
Florian Hahn d39b8a3533 [MachineCombiner] Update instruction depths incrementally for large BBs.
Summary:
For large basic blocks with lots of combinable instructions, the
MachineTraceMetrics computations in MachineCombiner can dominate the compile
time, as computing the trace information is quadratic in the number of
instructions in a BB and it's relevant successors/predecessors.

In most cases, knowing the instruction depth should be enough to make
combination decisions. As we already iterate over all instructions in a basic
block, the instruction depth can be computed incrementally. This reduces the
cost of machine-combine drastically in cases where lots of instructions
are combined. The major drawback is that AFAIK, computing the critical path
length cannot be done incrementally. Therefore we only compute
instruction depths incrementally, for basic blocks with more
instructions than inc_threshold. The -machine-combiner-inc-threshold
option can be used to set the threshold and allows for easier
experimenting and checking if using incremental updates for all basic
blocks has any impact on the performance.

Reviewers: sanjoy, Gerolf, MatzeB, efriedma, fhahn

Reviewed By: fhahn

Subscribers: kiranchandramohan, javed.absar, efriedma, llvm-commits

Differential Revision: https://reviews.llvm.org/D36619

llvm-svn: 312719
2017-09-07 12:49:39 +00:00
Jakub Kuderski 1d2dc681b1 [NFC] Move DEBUG_TYPE macro below includes...
in MachineCombiner.cpp.

llvm-svn: 307940
2017-07-13 19:30:52 +00:00
Matthias Braun 1527baab0c CodeGen: Rename DEBUG_TYPE to match passnames
Rename the DEBUG_TYPE to match the names of corresponding passes where
it makes sense. Also establish the pattern of simply referencing
DEBUG_TYPE instead of repeating the passname where possible.

llvm-svn: 303921
2017-05-25 21:26:32 +00:00
Eric Christopher 17ce8a2f5e Fix up grammar in a comment.
llvm-svn: 297898
2017-03-15 21:50:46 +00:00
Andrew V. Tischenko 8da96914f9 Compile time decreasing in the case we're dealing with Machine Combiner.
Before this patch compile time was about 21s (see below). After this patch
we have less than 2s (see bellow).

  Intel(R) Xeon(R) CPU E5-2676 v3 @ 2.40GHz

    DAGCombiner - trunk
        time ./llc spill_fdiv.ll -o /dev/null -enable-unsafe-fp-math
        real  0m1.685s

    DAGCombiner + Speed patch
        time ./llc spill_fdiv.ll -o /dev/null -enable-unsafe-fp-math
        real  0m1.655s

    MachineCombiner w/o Speed patch
        time ./llc spill_fdiv.ll -o /dev/null -enable-unsafe-fp-math
        real  0m21.614s

    MachineCombiner + Speed patch
        time ./llc spill_fdiv.ll -o /dev/null -enable-unsafe-fp-math
        real  0m1.593s

The test spill_fdiv.ll  is attached to D29627
D29627 should be closed.

llvm-svn: 294936
2017-02-13 09:43:37 +00:00
Matthias Braun a4976c6166 MachineInstr: Remove parameter from dump()
The primary use of the dump() functions in LLVM is for use in a
debugger. Unfortunately lldb does not seem to handle default arguments
so using `p SomeMI.dump()` fails and you have to type the longer `p
SomeMI.dump(nullptr)`. Remove the paramter to make the most common use
easy. (You can always construct something like `p
SomeMI.print(dbgs(),MyTII)` if you need more features).

Differential Revision: https://reviews.llvm.org/D29241

llvm-svn: 293440
2017-01-29 18:20:42 +00:00
Sebastian Pop 7779484313 machine combiner: fix pretty printer
we used to print UNKNOWN instructions when the instruction to be printer was not
yet inserted in any BB: in that case the pretty printer would not be able to
compute a TII as the instruction does not belong to any BB or function yet.
This patch explicitly passes the TII to the pretty-printer.

Differential Revision: https://reviews.llvm.org/D27645

llvm-svn: 290228
2016-12-21 01:41:12 +00:00
Sebastian Pop e08d9c7c87 instr-combiner: sum up all latencies of the transformed instructions
We have found that -- when the selected subarchitecture has a scheduling model
and we are not optimizing for size -- the machine-instruction combiner uses a
too-simple algorithm to compute the cost of one of the two alternatives [before
and after running a combining pass on a section of code], and therefor it throws
away the combination results too often.

This fix has the potential to help any ISA with the potential to combine
instructions and for which at least one subarchitecture has a scheduling model.
As of now, this is only known to definitely affect AArch64 subarchitectures with
a scheduling model.

Regression tested on AMD64/GNU-Linux, new test case tested to fail on an
unpatched compiler and pass on a patched compiler.

Patch by Abe Skolnik and Sebastian Pop.

llvm-svn: 289399
2016-12-11 19:39:32 +00:00
Mehdi Amini 117296c0a0 Use StringRef in Pass/PassManager APIs (NFC)
llvm-svn: 283004
2016-10-01 02:56:57 +00:00
Gerolf Hoflehner 01b3a6184a [MachineCombiner] Support for floating-point FMA on ARM64 (re-commit r267098)
The original patch caused crashes because it could derefence a null pointer
for SelectionDAGTargetInfo for targets that do not define it.

Evaluates fmul+fadd -> fmadd combines and similar code sequences in the
machine combiner. It adds support for float and double similar to the existing
integer implementation. The key features are:

- DAGCombiner checks whether it should combine greedily or let the machine
combiner do the evaluation. This is only supported on ARM64.
- It gives preference to throughput over latency: the heuristic used is
to combine always in loops. The targets decides whether the machine
combiner should optimize for throughput or latency.
- Supports for fmadd, f(n)msub, fmla, fmls patterns
- On by default at O3 ffast-math

llvm-svn: 267328
2016-04-24 05:14:01 +00:00
Daniel Sanders 591c379563 Revert r267098 - [MachineCombiner] Support for floating-point FMA on ARM64
It introduced buildbot failures on clang-cmake-mips, clang-ppc64le-linux, among others.

llvm-svn: 267127
2016-04-22 09:37:26 +00:00
Gerolf Hoflehner b32f11fc62 [MachineCombiner] Support for floating-point FMA on ARM64
Evaluates fmul+fadd -> fmadd combines and similar code sequences in the
machine combiner. It adds support for float and double similar to the existing
integer implementation. The key features are:

- DAGCombiner checks whether it should combine greedily or let the machine
combiner do the evaluation. This is only supported on ARM64.
- It gives preference to throughput over latency: the heuristic used is
to combine always in loops. The targets decides whether the machine
combiner should optimize for throughput or latency.
- Supports for fmadd, f(n)msub, fmla, fmls patterns
- On by default at O3 ffast-math

llvm-svn: 267098
2016-04-22 02:15:19 +00:00
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
Junmo Park 272a2bc365 Minor code cleanup. NFC.
llvm-svn: 262096
2016-02-27 01:10:43 +00:00
Duncan P. N. Exon Smith e59c8af705 Reapply "CodeGen: Use references in MachineTraceMetrics::Trace, NFC"
This reverts commit r261510, effectively reapplying r261509.  The
original commit missed a caller in AArch64ConditionalCompares.

Original commit message:

Pass non-null arguments by reference in MachineTraceMetrics::Trace,
simplifying future work to remove implicit iterator => pointer
conversions.

llvm-svn: 261511
2016-02-22 03:33:28 +00:00
Duncan P. N. Exon Smith 0cc90a9147 Revert "CodeGen: Use references in MachineTraceMetrics::Trace, NFC"
This reverts commit r261509.  I'm not sure how this compiled locally,
but something was out of whack.

llvm-svn: 261510
2016-02-22 03:12:42 +00:00
Duncan P. N. Exon Smith 83d3476fd2 CodeGen: Use references in MachineTraceMetrics::Trace, NFC
Pass non-null arguments by reference in MachineTraceMetrics::Trace,
simplifying future work to remove implicit iterator => pointer
conversions.

llvm-svn: 261509
2016-02-22 03:07:49 +00:00
Sanjay Patel 33ec5dbe35 less indent; NFCI
llvm-svn: 252643
2015-11-10 20:09:02 +00:00
Sanjay Patel 766589efdc add 'MustReduceDepth' as an objective/cost-metric for the MachineCombiner
This is one of the problems noted in PR25016:
https://llvm.org/bugs/show_bug.cgi?id=25016
and:
http://lists.llvm.org/pipermail/llvm-dev/2015-October/090998.html

The spilling problem is independent and not addressed by this patch.

The MachineCombiner was doing reassociations that don't improve or even worsen the critical path. 
This is caused by inclusion of the "slack" factor when calculating the critical path of the original
code sequence. If we don't add that, then we have a more conservative cost comparison of the old code
sequence vs. a new sequence. The more liberal calculation must be preserved, however, for the AArch64
MULADD patterns because benchmark regressions were observed without that.

The two failing test cases now have identical asm that does what we want:
a + b + c + d ---> (a + b) + (c + d)

Differential Revision: http://reviews.llvm.org/D13417

llvm-svn: 252616
2015-11-10 16:48:53 +00:00
Sanjay Patel 387e66e79f replace MachineCombinerPattern namespace and enum with enum class; NFCI
Also, remove an enum hack where enum values were used as indexes into an array.

We may want to make this a real class to allow pattern-based queries/customization (D13417).

llvm-svn: 252196
2015-11-05 19:34:57 +00:00
Hans Wennborg 083ca9bb32 Fix Clang-tidy modernize-use-nullptr warnings in source directories and generated files; other minor cleanups.
Patch by Eugene Zelenko!

Differential Revision: http://reviews.llvm.org/D13321

llvm-svn: 249482
2015-10-06 23:24:35 +00:00
Sanjay Patel acd4baefca include equal sign in debug equations; NFC
llvm-svn: 249248
2015-10-03 20:45:01 +00:00
Sanjay Patel 74ca312666 fix minsize detection: minsize attribute implies optimizing for size
llvm-svn: 244604
2015-08-11 14:31:14 +00:00
Hal Finkel 17caf326e5 [MachineCombiner] Don't use the opcode-only form of computeInstrLatency
In r242277, I updated the MachineCombiner to work with itineraries, but I
missed a call that is scheduling-model-only (the opcode-only form of
computeInstrLatency). Using the form that takes an MI* allows this to work with
itineraries (and should be NFC for subtargets with scheduling models).

llvm-svn: 244020
2015-08-05 07:45:28 +00:00
Sanjay Patel 924879ad2c wrap OptSize and MinSize attributes for easier and consistent access (NFCI)
Create wrapper methods in the Function class for the OptimizeForSize and MinSize
attributes. We want to hide the logic of "or'ing" them together when optimizing
just for size (-Os).

Currently, we are not consistent about this and rely on a front-end to always set
OptimizeForSize (-Os) if MinSize (-Oz) is on. Thus, there are 18 FIXME changes here
that should be added as follow-on patches with regression tests.

This patch is NFC-intended: it just replaces existing direct accesses of the attributes
by the equivalent wrapper call.

Differential Revision: http://reviews.llvm.org/D11734

llvm-svn: 243994
2015-08-04 15:49:57 +00:00
Hal Finkel e0fa8f2c86 [MachineCombiner] Work with itineraries
MachineCombiner predicated its use of scheduling-based metrics on
hasInstrSchedModel(), but useful conclusions can be drawn from pipeline
itineraries as well. Almost all of the logic (except for resource tracking in
preservesResourceLen) can be used if we have an itinerary, so enable it in that
case as well.

This will be used by the PowerPC backend in an upcoming commit.

llvm-svn: 242277
2015-07-15 08:22:23 +00:00
Alexander Kornienko f00654e31b Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.

llvm-svn: 240390
2015-06-23 09:49:53 +00:00
Sanjay Patel e79b43a01f [x86] generalize reassociation optimization in machine combiner to 2 instructions
Currently ( D10321, http://reviews.llvm.org/rL239486 ), we can use the machine combiner pass
to reassociate the following sequence to reduce the critical path:

A = ? op ?
B = A op X
C = B op Y
-->
A = ? op ?
B = X op Y
C = A op B

'op' is currently limited to x86 AVX scalar FP adds (with fast-math on), but in theory, it could
be any associative math/logic op (see TODO in code comment).

This patch generalizes the pattern match to ignore the instruction that defines 'A'. So instead of
a sequence of 3 adds, we now only need to find 2 dependent adds and decide if it's worth
reassociating them.

This generalization has a compile-time cost because we can now match more instruction sequences
and we rely more heavily on the machine combiner to discard sequences where reassociation doesn't
improve the critical path.

For example, in the new test case:

A = M div N
B = A add X
C = B add Y

We'll match 2 reassociation patterns, but this transform doesn't reduce the critical path:

A = M div N
B = A add Y
C = B add X

We need the combiner to reject that pattern but select this:

A = M div N
B = X add Y
C = B add A

Differential Revision: http://reviews.llvm.org/D10460

llvm-svn: 240361
2015-06-23 00:39:40 +00:00
Sanjay Patel cfe0393b82 name change: hasPattern() -> getMachineCombinerPatterns() ; NFC
This was suggested as part of D10460, but it's independent of
any functional change.

llvm-svn: 240192
2015-06-19 23:21:42 +00:00
Alexander Kornienko 70bc5f1398 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!

llvm-svn: 240137
2015-06-19 15:57:42 +00:00
Sanjay Patel 5714998484 hoist loop-invariant; NFCI
llvm-svn: 239681
2015-06-13 15:33:15 +00:00
Sanjay Patel 85924e5bf3 remove unnecessary casts; NFCI
llvm-svn: 239678
2015-06-13 15:06:33 +00:00
Sanjay Patel ccb8d5cc57 punctuation policing; NFC
llvm-svn: 239484
2015-06-10 19:52:58 +00:00