Commit Graph

27 Commits

Author SHA1 Message Date
dfukalov 167767a775 SpeculativeExecution: Fix for logic change introduced in D81730.
Summary:
The test case started to hoist bitcasts to upper BB after D81730.
Reverted unintentional logic change. Some instructions may have zero cost but
will not be hoisted by different limitation so should be counted for threshold.

Reviewers: aprantl, arsenm, nhaehnle

Reviewed By: aprantl

Subscribers: wdng, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82761
2020-07-09 15:45:23 +03:00
dfukalov c7bcd431d9 SpeculativeExecution: fix incorrect debug info move
Summary:
Debug info related instructions got zero cost so hoisted unconditionally

Bugzilla: https://bugs.llvm.org/show_bug.cgi?id=46267

Reviewers: arsenm, nhaehnle, chandlerc, aprantl

Reviewed By: aprantl

Subscribers: ormris, uabelho, wdng, aprantl, hiraditya, llvm-commits

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D81730
2020-06-28 14:35:00 +03:00
Eric Christopher 10563e16aa [Analysis/Transforms/Sanitizers] As part of using inclusive language
within the llvm project, migrate away from the use of blacklist and
whitelist.
2020-06-20 00:42:26 -07:00
Sam Parker e9c9329aa4 [TTI] Add TargetCostKind argument to getUserCost
There are several different types of cost that TTI tries to provide
explicit information for: throughput, latency, code size along with
a vague 'intersection of code-size cost and execution cost'.

The vectorizer is a keen user of RecipThroughput and there's at least
'getInstructionThroughput' and 'getArithmeticInstrCost' designed to
help with this cost. The latency cost has a single use and a single
implementation. The intersection cost appears to cover most of the
rest of the API.

getUserCost is explicitly called from within TTI when the user has
been explicit in wanting the code size (also only one use) as well
as a few passes which are concerned with a mixture of size and/or
a relative cost. In many cases these costs are closely related, such
as when multiple instructions are required, but one evident diverging
cost in this function is for div/rem.

This patch adds an argument so that the cost required is explicit,
so that we can make the important distinction when necessary.

Differential Revision: https://reviews.llvm.org/D78635
2020-04-28 08:57:45 +01:00
dfukalov dbfc682e2b SpeculativeExecution: fixed ingoring free execution
Summary:
After updating cost model in AMDGPU target (47a5c36b37) the pass started to
ignore some BBs since they got all instructions estimated as free.

Reviewers: arsenm, chandlerc, nhaehnle

Reviewed By: nhaehnle

Subscribers: jvesely, wdng, nhaehnle, tpr, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74825
2020-02-20 14:45:02 +03:00
Reid Kleckner 05da2fe521 Sink all InitializePasses.h includes
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
  recompiles    touches affected_files  header
  342380        95      3604    llvm/include/llvm/ADT/STLExtras.h
  314730        234     1345    llvm/include/llvm/InitializePasses.h
  307036        118     2602    llvm/include/llvm/ADT/APInt.h
  213049        59      3611    llvm/include/llvm/Support/MathExtras.h
  170422        47      3626    llvm/include/llvm/Support/Compiler.h
  162225        45      3605    llvm/include/llvm/ADT/Optional.h
  158319        63      2513    llvm/include/llvm/ADT/Triple.h
  140322        39      3598    llvm/include/llvm/ADT/StringRef.h
  137647        59      2333    llvm/include/llvm/Support/Error.h
  131619        73      1803    llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211
2019-11-13 16:34:37 -08:00
Cameron McInally 7c5c0c9fe5 Support FNeg in SpeculativeExecution pass
Differential Revision: https://reviews.llvm.org/D61910

llvm-svn: 360692
2019-05-14 16:51:18 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Florian Hahn a1cc848399 Use SmallPtrSet explicitly for SmallSets with pointer types (NFC).
Currently SmallSet<PointerTy> inherits from SmallPtrSet<PointerTy>. This
patch replaces such types with SmallPtrSet, because IMO it is slightly
clearer and allows us to get rid of unnecessarily including SmallSet.h

Reviewers: dblaikie, craig.topper

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D47836

llvm-svn: 334492
2018-06-12 11:16:56 +00:00
Michael Zolotukhin 31800864dc SpeculativeExecution Pass: Set PreserveCFG to avoid unnecessary analyses invalidation.
The pass doesn't touch CFG in any way, only moves instructions between
blocks.

llvm-svn: 334150
2018-06-07 00:19:29 +00:00
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
Chandler Carruth f3bd8ddedb Revert r301950: SpeculativeExecution: Stop using whitelist for costs
This pass doesn't correctly handle testing for when it is legal to hoist
arbitrary instructions. The whitelist happens to make it safe, so before
it is removed the pass's legality checks will need to be enhanced.

Details have been added to the code review thread for the patch.

llvm-svn: 302640
2017-05-10 12:30:07 +00:00
Matt Arsenault 9ac7d6be3c SpeculativeExecution: Stop using whitelist for costs
Just let TTI's cost do this instead of arbitrarily restricting
this.

llvm-svn: 301950
2017-05-02 18:02:18 +00:00
Matt Arsenault ef00283425 SpeculativeExecution: Allow speculating more inst types
Partial step towards removing the whitelist and only
using TTI's cost.

llvm-svn: 285438
2016-10-28 20:00:33 +00:00
Mehdi Amini 117296c0a0 Use StringRef in Pass/PassManager APIs (NFC)
llvm-svn: 283004
2016-10-01 02:56:57 +00:00
Michael Kuperstein c40618610f [PM] Port SpeculativeExecution to the new PM
Differential Revision: https://reviews.llvm.org/D23033

llvm-svn: 277393
2016-08-01 21:48:33 +00:00
Kristof Beyls c08f70588d Mark that SpeculativeExecution preserves Globals Alias Analysis.
A few benchmarks with lots of accesses to global variables in the hot
loops regressed a lot since r266399, which added the
SpeculativeExecution pass to the default pipeline. The problem is that
this pass doesn't mark Globals Alias Analysis as preserved. Globals
Alias Analysis is computed in a module pass, whereas
SpeculativeExecution is a function pass, and a lot of passes dependent
on the Globals Alias Analysis to optimize these benchmarks are also
function passes. As such, the Globals Alias Analysis information cannot
be recomputed between SpeculativeExecution and the following function
passes needing that information.

SpeculativeExecution doesn't invalidate Globals Alias Analysis, so mark
it as such to fix those performance regressions.

Differential Revision: http://reviews.llvm.org/D19806

llvm-svn: 268370
2016-05-03 08:33:26 +00:00
Chad Rosier fcb2210812 Typo. NFC.
llvm-svn: 268280
2016-05-02 19:06:04 +00:00
Chad Rosier 4466ff50eb Use false rather than 0 for a boolean value. NFC.
llvm-svn: 268279
2016-05-02 19:06:02 +00:00
Andrew Kaylor aa641a5171 Re-commit optimization bisect support (r267022) without new pass manager support.
The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling).

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267231
2016-04-22 22:06:11 +00:00
Vedant Kumar 6013f45f92 Revert "Initial implementation of optimization bisect support."
This reverts commit r267022, due to an ASan failure:

  http://lab.llvm.org:8080/green/job/clang-stage2-cmake-RgSan_check/1549

llvm-svn: 267115
2016-04-22 06:51:37 +00:00
Andrew Kaylor f0f279291c Initial implementation of optimization bisect support.
This patch implements a optimization bisect feature, which will allow optimizations to be selectively disabled at compile time in order to track down test failures that are caused by incorrect optimizations.

The bisection is enabled using a new command line option (-opt-bisect-limit).  Individual passes that may be skipped call the OptBisect object (via an LLVMContext) to see if they should be skipped based on the bisect limit.  A finer level of control (disabling individual transformations) can be managed through an addition OptBisect method, but this is not yet used.

The skip checking in this implementation is based on (and replaces) the skipOptnoneFunction check.  Where that check was being called, a new call has been inserted in its place which checks the bisect limit and the optnone attribute.  A new function call has been added for module and SCC passes that behaves in a similar way.

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267022
2016-04-21 17:58:54 +00:00
Justin Lebar cad81cf6b3 [Speculation] Add a SpeculativeExecution mode where the pass does nothing unless TTI::hasBranchDivergence() is true.
Summary:
This lets us add this pass to the IR pass manager unconditionally; it
will simply not do anything on targets without branch divergence.

Reviewers: tra

Subscribers: llvm-commits, jingyue, rnk, chandlerc

Differential Revision: http://reviews.llvm.org/D18625

llvm-svn: 266398
2016-04-15 00:32:09 +00:00
Duncan P. N. Exon Smith be4d8cba1c Scalar: Remove remaining ilist iterator implicit conversions
Remove remaining `ilist_iterator` implicit conversions from
LLVMScalarOpts.

This change exposed some scary behaviour in
lib/Transforms/Scalar/SCCP.cpp around line 1770.  This patch changes a
call from `Function::begin()` to `&Function::front()`, since the return
was immediately being passed into another function that takes a
`Function*`.  `Function::front()` started to assert, since the function
was empty.  Note that `Function::end()` does not point at a legal
`Function*` -- it points at an `ilist_half_node` -- so the other
function was getting garbage before.  (I added the missing check for
`Function::isDeclaration()`.)

Otherwise, no functionality change intended.

llvm-svn: 250211
2015-10-13 19:26:58 +00:00
Jingyue Wu 5db9cba066 [Speculation] NFC: more header comments
explaining how it differs from SpeculativeExecuteBB in SimplifyCFG.

llvm-svn: 237724
2015-05-19 20:52:45 +00:00
Benjamin Kramer d9f06c8b87 Move Pass into anonymous namespace. NFC.
llvm-svn: 237526
2015-05-16 16:16:35 +00:00
Jingyue Wu 154eb5aa1d Add a speculative execution pass
Summary:
This is a pass for speculative execution of instructions for simple if-then (triangle) control flow. It's aimed at GPUs, but could perhaps be used in other contexts. Enabling this pass gives us a 1.0% geomean improvement on Google benchmark suites, with one benchmark improving 33%.

Credit goes to Jingyue Wu for writing an earlier version of this pass.

Patched by Bjarke Roune. 

Test Plan:
This patch adds a set of tests in test/Transforms/SpeculativeExecution/spec.ll
The pass is controlled by a flag which defaults to having the pass not run.

Reviewers: eliben, dberlin, meheff, jingyue, hfinkel

Reviewed By: jingyue, hfinkel

Subscribers: majnemer, jholewinski, llvm-commits

Differential Revision: http://reviews.llvm.org/D9360

llvm-svn: 237459
2015-05-15 17:54:48 +00:00