Commit Graph

48 Commits

Author SHA1 Message Date
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
Fangrui Song cb0bab86b3 [CodeGen] Fix inconsistent declaration parameter name
llvm-svn: 337200
2018-07-16 18:51:40 +00:00
Heejin Ahn d69acf3b4c Change ambiguous uses of term 'funclet' to 'EH scopes'. NFC.
Summary:
`getEHScopeMembership()` function is used not only for funclet-based
EHs; they apply to all EH schemes that use the scoped IR
(catchpad/cleanuppad/...). D47005 (rL333045) changed some of the uses of
the term 'funclet' to 'EH scopes' in case they apply to all scoped EH,
and this fixes more of them. For `FuncletLayout` pass, I left it as is
because the pass is only used for funclet-based EH.

Reviewers: majnemer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47611

llvm-svn: 333711
2018-06-01 00:03:21 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Eugene Zelenko 149178d92b [CodeGen] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 315380
2017-10-10 22:33:29 +00:00
Matthias Braun c9056b834d Insert IMPLICIT_DEFS for undef uses in tail merging
Tail merging can convert an undef use into a normal one when creating a
common tail. Doing so can make the register live out from a block which
previously contained the undef use. To keep the liveness up-to-date,
insert IMPLICIT_DEFs in such blocks when necessary.

To enable this patch the computeLiveIns() function which used to
compute live-ins for a block and set them immediately is split into new
functions:
- computeLiveIns() just computes the live-ins in a LivePhysRegs set.
- addLiveIns() applies the live-ins to a block live-in list.
- computeAndAddLiveIns() is a convenience function combining the other
  two functions and behaving like computeLiveIns() before this patch.

Based on a patch by Krzysztof Parzyszek <kparzysz@codeaurora.org>

Differential Revision: https://reviews.llvm.org/D37034

llvm-svn: 312668
2017-09-06 20:45:24 +00:00
Matthias Braun e51c435c07 LivePhysRegs: Skip reserved regs in computeLiveIns; NFCI
Re-commit r303937 + r303949 as they were not the cause for the build
failures.

We do not track liveness of reserved registers so adding them to the
liveins list in computeLiveIns() was completely unnecessary.

llvm-svn: 303970
2017-05-26 06:32:31 +00:00
Matthias Braun f56a6d84b6 Revert "LivePhysRegs: Skip reserved regs in computeLiveIns; NFCI"
Tentatively revert, suspecting that it caused breakage in stage2
buildbots.

This reverts commit r303949.
This reverts commit r303937.

llvm-svn: 303955
2017-05-26 01:29:32 +00:00
Matthias Braun 9512dd5ffd LivePhysRegs: Skip reserved regs in computeLiveIns; NFCI
We do not track liveness of reserved registers so adding them to the
liveins list in computeLiveIns() was completely unnecessary.

llvm-svn: 303937
2017-05-25 23:39:33 +00:00
Taewook Oh 1b192336d8 NFC: Reformats comments according to the coding guildelines.
llvm-svn: 297808
2017-03-15 06:29:23 +00:00
Taewook Oh fb1833efeb [BranchFolding] Merge debug locations from common tail instead of removing
Summary: D25742 improved the precision of debug locations for PGO by removing debug locations from common tail when tail-merging. However, if identical insturctions that are merged into a common tail have the same debug locations, there's no need to remove them. This patch creates a merged debug location of identical instructions across SameTails and assign it to the instruction in the common tail, so that the debug locations are maintained if they are same across identical instructions.

Reviewers: aprantl, probinson, MatzeB, rob.lougher

Reviewed By: aprantl

Subscribers: andreadb, llvm-commits

Differential Revision: https://reviews.llvm.org/D30226

llvm-svn: 297805
2017-03-15 05:44:59 +00:00
Xinliang David Li 538d666814 include function name in dot filename
Differential Revision: http://reviews.llvm.org/D29975

llvm-svn: 295220
2017-02-15 19:21:04 +00:00
Kyle Butt b15c06677c CodeGen: Allow small copyable blocks to "break" the CFG.
When choosing the best successor for a block, ordinarily we would have preferred
a block that preserves the CFG unless there is a strong probability the other
direction. For small blocks that can be duplicated we now skip that requirement
as well, subject to some simple frequency calculations.

Differential Revision: https://reviews.llvm.org/D28583

llvm-svn: 293716
2017-01-31 23:48:32 +00:00
Xinliang David Li fd3f645f9d Add support to dump dot graph block layout after MBP
Differential Revision: https://reviews.llvm.org/D29141

llvm-svn: 293408
2017-01-29 01:57:02 +00:00
Matthias Braun 181983055f BranchRelaxation: Recompute live-ins when splitting a block
Factors out and reuses live-in computation code from BranchFolding.

Differential Revision: https://reviews.llvm.org/D27558

llvm-svn: 290013
2016-12-16 23:55:37 +00:00
Krzysztof Parzyszek 8271be9a1d Do not remove implicit defs in BranchFolder
Branch folder removes implicit defs if they are the only non-branching
instructions in a block, and the branches do not use the defined registers.
The problem is that in some cases these implicit defs are required for
the liveness information to be correct.

Differential Revision: https://reviews.llvm.org/D25478

llvm-svn: 284036
2016-10-12 19:50:57 +00:00
Kyle Butt 64e428147f Branch Folding: Accept explicit threshold for tail merge size.
This is prep work for allowing the threshold to be different during layout,
and to enforce a single threshold between merging and duplicating during
layout. No observable change intended.

llvm-svn: 279117
2016-08-18 18:57:29 +00:00
Matthias Braun aeab09fb8f BranchFolding: Use LivePhysReg to update live in lists.
Use LivePhysRegs with a backwards walking algorithm to update live in
lists, this way the results do not depend on the presence of kill flags
anymore.

This patch also reduces the number of registers added as live-in.
Previously all pristine registers as well as all sub registers of a
super register were added resulting in unnecessarily large live in
lists. This fixed https://llvm.org/PR25263.

Differential Revision: http://reviews.llvm.org/D22027

llvm-svn: 275201
2016-07-12 18:44:33 +00:00
Haicheng Wu 5b458cc1f6 Reapply "[MBP] Reduce code size by running tail merging in MBP.""
This reapplies commit r271930, r271915, r271923.  They hit a bug in
Thumb which is fixed in r272258 now.

The original message:

The code layout that TailMerging (inside BranchFolding) works on is not the
final layout optimized based on the branch probability. Generally, after
BlockPlacement, many new merging opportunities emerge.

This patch calls Tail Merging after MBP and calls MBP again if Tail Merging
merges anything.

llvm-svn: 272267
2016-06-09 15:24:29 +00:00
Haicheng Wu 4fa9f3ae45 Revert "[MBP] Reduce code size by running tail merging in MBP."
This reverts commit r271930, r271915, r271923.  They break a thumb selfhosting
bot.

llvm-svn: 272017
2016-06-07 15:17:21 +00:00
Haicheng Wu 77ea344786 [MBP] Reduce code size by running tail merging in MBP.
The code layout that TailMerging (inside BranchFolding) works on is not the
final layout optimized based on the branch probability. Generally, after
BlockPlacement, many new merging opportunities emerge.

This patch calls Tail Merging after MBP and calls MBP again if Tail Merging
merges anything.

Differential Revision: http://reviews.llvm.org/D20276

llvm-svn: 271925
2016-06-06 18:36:07 +00:00
Haicheng Wu 664b561f01 [BranchFolding] Replace MachineBlockFrequencyInfo with MBFIWrapper. NFC.
Differential Revision: http://reviews.llvm.org/D20184

llvm-svn: 271923
2016-06-06 18:35:41 +00:00
David Majnemer 161935520d [WinEH] Permit branch folding in the face of funclets
Track which basic blocks belong to which funclets.  Permit branch
folding to fire but only if it can prove that doing so will not cause
code in one funclet to be reused in another.

llvm-svn: 249257
2015-10-04 02:22:52 +00:00
Benjamin Kramer f4c2025357 [CodeGen] Reduce visibility of implementation details
NFC.

llvm-svn: 241164
2015-07-01 14:47:39 +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
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
Benjamin Kramer a7c40ef022 Canonicalize header guards into a common format.
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)

Changes made by clang-tidy with minor tweaks.

llvm-svn: 215558
2014-08-13 16:26:38 +00:00
Akira Hatanaka bbd33f6766 [Branch probability] Recompute branch weights of tail-merged basic blocks.
BranchFolderPass was not correctly setting the basic block branch weights when
tail-merging created or merged blocks. This patch recomutes the weights of
tail-merged blocks using the following formula:

branch_weight(merged block to successor j) =
sum(block_frequency(bb) * branch_probability(bb -> j))

bb is a block that is in the set of merged blocks.

<rdar://problem/16256423>

llvm-svn: 215135
2014-08-07 19:30:13 +00:00
Benjamin Kramer 079b96e6f7 Revert "Give internal classes hidden visibility."
It works with clang, but GCC has different rules so we can't make all of those
hidden. This reverts commit r190534.

llvm-svn: 190536
2013-09-11 18:05:11 +00:00
Benjamin Kramer 6a44af3629 Give internal classes hidden visibility.
Worth 100k on a linux/x86_64 Release+Asserts clang.

llvm-svn: 190534
2013-09-11 17:42:27 +00:00
Michael Gottesman 1649a877e1 [branchfolding] Fix typo in C++ editor declaration.
llvm-svn: 188201
2013-08-12 20:49:27 +00:00
Andrew Trick 97a1d7c475 Fix tail merging to assign the (more) correct BasicBlock when splitting.
This makes it possible to write unit tests that are less susceptible
to minor code motion, particularly copy placement. block-placement.ll
covers this case with -pre-RA-sched=source which will soon be
default. One incorrectly named block is already fixed, but without
this fix, enabling new coalescing and scheduling would cause more
failures.

llvm-svn: 184680
2013-06-24 01:55:01 +00:00
Eli Friedman bf007364bf When tail-merging multiple blocks, make sure to correctly update the live-in list on the merged block to correctly account for the live-outs of all the predecessors. They might not be the same in all cases (the testcase I have involves a PHI node where one of the operands is an IMPLICIT_DEF).
Unfortunately, the testcase I have is large and confidential, so I don't have a test to commit at the moment; I'll see if I can come up with something smaller where this issue reproduces.

<rdar://problem/9716278>

llvm-svn: 134565
2011-07-06 23:41:48 +00:00
Rafael Espindola 3aeaf9e4c1 Add 132986 back, but avoid non-determinism if a bb address gets reused.
llvm-svn: 132995
2011-06-14 15:31:54 +00:00
Rafael Espindola 06ba7a68de revert 132986 to see if the bots go green.
llvm-svn: 132988
2011-06-14 12:48:26 +00:00
Rafael Espindola da24f2f8e1 Make the threshold used by branch folding softer. Before we would get a
sharp all or nothing transition when one extra predecessor was added. Now
we still test first ones for merging.

llvm-svn: 132974
2011-06-14 04:41:17 +00:00
Evan Cheng cfdf33904b Re-commit 131172 with fix. MachineInstr identity checks should check dead
markers. In some cases a register def is dead on one path, but not on
another.

This is passing Clang self-hosting.

llvm-svn: 131214
2011-05-12 00:56:58 +00:00
Rafael Espindola 2a09d65979 Revert 131172 as it is causing clang to miscompile itself. I will try
to provide a reduced testcase.

llvm-svn: 131176
2011-05-11 03:27:17 +00:00
Evan Cheng 05fc35e275 Add a late optimization to BranchFolding that hoist common instruction sequences
at the start of basic blocks to their common predecessor. It's actually quite
common (e.g. about 50 times in JM/lencod) and has shown to be a nice code size
benefit. e.g.

        pushq   %rax
        testl   %edi, %edi
        jne     LBB0_2
## BB#1:
        xorb    %al, %al
        popq    %rdx
        ret
LBB0_2:
        xorb    %al, %al
        callq   _foo
        popq    %rdx
        ret

=>

        pushq   %rax
        xorb    %al, %al
        testl   %edi, %edi
        je      LBB0_2
## BB#1:
        callq   _foo
LBB0_2:
        popq    %rdx
        ret

rdar://9145558

llvm-svn: 131172
2011-05-11 01:03:01 +00:00
Evan Cheng 37bb617f8a Tail merging pass shall not break up IT blocks. rdar://8115404
llvm-svn: 106517
2010-06-22 01:18:16 +00:00
Bob Wilson 2d4ff12da9 Split tail duplication into a separate pass. This is needed to avoid
running tail duplication when doing branch folding for if-conversion, and
we also want to be able to run tail duplication earlier to fix some
reg alloc problems.  Move the CanFallThrough function from BranchFolding
to MachineBasicBlock so that it can be shared by TailDuplication.

llvm-svn: 89904
2009-11-26 00:32:21 +00:00
Bob Wilson bd22f1965d Perform tail duplication only once, after tail merging is complete.
It was too difficult to keep the heuristics for merging and duplication
consistent.

llvm-svn: 89105
2009-11-17 17:06:18 +00:00
Dan Gohman a9b40a6eb4 Make the BranchFolderPass class local to BranchFolding.cpp.
llvm-svn: 86928
2009-11-12 01:59:26 +00:00
Dan Gohman 02b155427e Promote MergePotentialsElt and SameTailElt to be regular classes
instead of typedefs for std::pair. This simplifies the type of
SameTails, which previously was std::vector<std::pair<std::vector<std::pair<unsigned, MachineBasicBlock *> >::iterator, MachineBasicBlock::iterator>

llvm-svn: 86885
2009-11-11 21:57:02 +00:00
Dan Gohman 34eeb4e983 Check in the changes to this file too.
llvm-svn: 86873
2009-11-11 19:49:34 +00:00
Bob Wilson 97b9312663 Revert r85346 change to control tail merging by CodeGenOpt::Level.
I'm going to redo this using the OptimizeForSize function attribute.

llvm-svn: 85426
2009-10-28 20:46:46 +00:00
Bob Wilson 9693f9d465 Record CodeGen optimization level in the BranchFolding pass so that we can
use it to control tail merging when there is a tradeoff between performance
and code size.  When there is only 1 instruction in the common tail, we have
been merging.  That can be good for code size but is a definite loss for
performance.  Now we will avoid tail merging in that case when the
optimization level is "Aggressive", i.e., "-O3".  Radar 7338114.

Since the IfConversion pass invokes BranchFolding, it too needs to know
the optimization level.  Note that I removed the RegisterPass instantiation
for IfConversion because it required a default constructor.  If someone
wants to keep that for some reason, we can add a default constructor with
a hard-wired optimization level.

llvm-svn: 85346
2009-10-27 23:49:38 +00:00
Evan Cheng 3d2fce01aa Run branch folding if if-converter make some transformations.
llvm-svn: 80994
2009-09-04 07:47:40 +00:00