74 Commits

Author SHA1 Message Date
Sanjay Patel
080999b5bb [ConstantHoisting] avoid hang/crash from unreachable blocks (PR40930)
I'm not too familiar with this pass, so there might be a better
solution, but this appears to fix the degenerate:
PR40930
PR40931
PR40932
PR40934
...without affecting any real-world code.

As we've seen in several other passes, when we have unreachable blocks,
they can contain semi-bogus IR and/or cause unexpected conditions. We
would not typically expect these patterns to make it this far, but we
have to guard against them anyway.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355337 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-04 20:57:14 +00:00
Fangrui Song
b1f04183c4 [ConstantHoisting] Call cleanup() in ConstantHoistingPass::runImpl to avoid dangling elements in ConstIntInfoVec for new PM
Summary:
ConstIntInfoVec contains elements extracted from the previous function.
In new PM, releaseMemory() is not called and the dangling elements can
cause segfault in findConstantInsertionPoint.

Rename releaseMemory() to cleanup() to deliver the idea that it is
mandatory and call cleanup() in ConstantHoistingPass::runImpl to fix
this.

Reviewers: ormris, zzheng, dmgreen, wmi

Reviewed By: ormris, wmi

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58589

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355174 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-01 05:27:01 +00:00
Chandler Carruth
6b547686c5 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-19 08:50:56 +00:00
Zhaoshi Zheng
c1271f6cb4 Revert "Revert "[ConstHoist] Do not rebase single (or few) dependent constant""
This reverts commit bd7b44f35ee9fbe365eb25ce55437ea793b39346.

Reland r342994: disabled the optimization and explicitly enable it in test.

-mllvm -consthoist-min-num-to-rebase<unsigned>=0

[ConstHoist] Do not rebase single (or few) dependent constant

If an instance (InsertionPoint or IP) of Base constant A has only one or few
rebased constants depending on it, do NOT rebase. One extra ADD instruction is
required to materialize each rebased constant, assuming A and the rebased have
the same materialization cost.

Differential Revision: https://reviews.llvm.org/D52243

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@343053 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-26 00:59:09 +00:00
Jessica Paquette
bd7b44f35e Revert "[ConstHoist] Do not rebase single (or few) dependent constant"
This caused a couple test failures on a bot:

CodeGen/X86/constant-hoisting-bfi.ll
Transforms/ConstantHoisting/X86/ehpad.ll

Example:

http://green.lab.llvm.org/green/job/clang-stage1-cmake-RA-incremental/53575/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@343005 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-25 18:41:40 +00:00
Zhaoshi Zheng
0d75a2849c [ConstHoist] Do not rebase single (or few) dependent constant
If an instance (InsertionPoint or IP) of Base constant A has only one or few
rebased constants depending on it, do NOT rebase. One extra ADD instruction is
required to materialize each rebased constant, assuming A and the rebased have
the same materialization cost.

Differential Revision: https://reviews.llvm.org/D52243

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@342994 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-25 17:45:37 +00:00
Zhaoshi Zheng
e4422b6a2a Revert "Revert r341269: [Constant Hoisting] Hoisting Constant GEP Expressions"
Reland r341269. Use std::stable_sort when sorting constant condidates.

Reverting commit, r341365:

  Revert r341269: [Constant Hoisting] Hoisting Constant GEP Expressions

  One of the tests is failing 50% of the time when expensive checks are
  enabled. Not sure how deep the problem is so just reverting while the
  author can investigate so that the bots stop repeatedly failing and
  blaming things incorrectly. Will respond with details on the original
  commit.

Original commit, r341269:

  [Constant Hoisting] Hoisting Constant GEP Expressions

  Leverage existing logic in constant hoisting pass to transform constant GEP
  expressions sharing the same base global variable. Multi-dimensional GEPs are
  rewritten into single-dimensional GEPs.

  https://reviews.llvm.org/D51396

Differential Revision: https://reviews.llvm.org/D51654

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341417 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-04 22:17:03 +00:00
Chandler Carruth
1381c3b1f0 Revert r341269: [Constant Hoisting] Hoisting Constant GEP Expressions
One of the tests is failing 50% of the time when expensive checks are
enabled. Not sure how deep the problem is so just reverting while the
author can investigate so that the bots stop repeatedly failing and
blaming things incorrectly. Will respond with details on the original
commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341365 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-04 13:36:44 +00:00
Zhaoshi Zheng
f6dfc5edb0 [Constant Hoisting] Hoisting Constant GEP Expressions
Leverage existing logic in constant hoisting pass to transform constant GEP
expressions sharing the same base global variable. Multi-dimensional GEPs are
rewritten into single-dimensional GEPs.

Differential Revision: https://reviews.llvm.org/D51396

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341269 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-01 00:04:56 +00:00
Zhaoshi Zheng
b9ba94c02a [QTOOL-37352] Consider isLegalAddressingImm in Constant Hoisting
In Thumb1, legal imm range is [0, 255] for ADD/SUB instructions. However, the
legal imm range for LD/ST in (R+Imm) addressing mode is [0, 127]. Imms in
[128, 255] are materialized by mov R, #imm, and LD/STs use them in (R+R)
addressing mode.

This patch checks if a constant is used as offset in (R+Imm), if so, it checks
isLegalAddressingMode passing the constant value as BaseOffset.

Differential Revision: https://reviews.llvm.org/D50931

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340882 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-28 23:00:59 +00:00
Fangrui Song
af7b1832a0 Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338293 91177308-0d34-0410-b5e6-96231b3b80d8
2018-07-30 19:41:25 +00:00
David Blaikie
8325fb20d4 Move Analysis/Utils/Local.h back to Transforms
Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change only moved the header and not the implementation anyway - which
was fine for the one function that was used (since it's a
template/inlined in the header) but not in general)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333954 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-04 21:23:21 +00:00
Nicola Zaghen
0818e789cb 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



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332240 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-14 12:53:11 +00:00
Adrian Prantl
26b584c691 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331272 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-01 15:54:18 +00:00
Mandeep Singh Grang
15ff8cad10 [Transforms] Change std::sort to llvm::sort in response to r327219
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: kcc, pcc, danielcdh, jmolloy, sanjoy, dberlin, ruiu

Reviewed By: ruiu

Subscribers: ruiu, llvm-commits

Differential Revision: https://reviews.llvm.org/D45142

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@330059 91177308-0d34-0410-b5e6-96231b3b80d8
2018-04-13 19:47:57 +00:00
David Blaikie
283527b390 Fix a couple of layering violations in Transforms
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.

Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.

Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@328165 91177308-0d34-0410-b5e6-96231b3b80d8
2018-03-21 22:34:23 +00:00
Paul Robinson
4c7c4551f2 Fix out-of-order stepping behavior in programs with hoisted constants.
When the Constant Hoisting pass moves expensive constants into a
common block, it would assign a debug location equal to the last use
of that constant. While this is certainly intuitive, it places the
constant in an out-of-order location, according to the debug location
information. This produces out-of-order stepping when debugging
programs affected by this pass.

This patch creates in-order stepping behavior by merging the debug
locations for hoisted constants, and the new insertion point.

Patch by Matthew Voss!

Differential Revision: https://reviews.llvm.org/D38088

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317827 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-09 20:01:31 +00:00
Eugene Zelenko
c49953f5fe [Transforms] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313198 91177308-0d34-0410-b5e6-96231b3b80d8
2017-09-13 21:43:53 +00:00
Leo Li
581e763cd4 [ConstantHoisting] Remove dupliate logic in constant hoisting
Summary:
As metioned in https://reviews.llvm.org/D34576, checkings in
`collectConstantCandidates` can be replaced by using
`llvm::canReplaceOperandWithVariable`.

The only special case is that `collectConstantCandidates` return false for
all `IntrinsicInst` but it is safe for us to collect constant candidates from
`IntrinsicInst`.

Reviewers: pirama, efriedma, srhines

Reviewed By: efriedma

Subscribers: llvm-commits, javed.absar

Differential Revision: https://reviews.llvm.org/D34921

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307587 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-10 20:45:34 +00:00
Wei Mi
0082096cc7 [ConstHoisting] Turn on consthoist-with-block-frequency by default.
Using profile information to guide consthoisting is generally helpful for
performance, so the patch turns it on by default. No compile time or perf
regression were found using spec2000 and spec2006 on x86.  Some significant
improvement (>20%) was seen on internal benchmarks.

Differential Revision: https://reviews.llvm.org/D35063


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307338 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-07 00:11:05 +00:00
Wei Mi
8e52a552c3 [ConstHoisting] choose to hoist when frequency is the same.
The patch is to adjust the strategy of frequency based consthoisting:
Previously when the candidate block has the same frequency with the existing
blocks containing a const, it will not hoist the const to the candidate block.
For that case, now we change the strategy to hoist the const if only existing
blocks have more than one block member. This is helpful for reducing code size.

Differential Revision: https://reviews.llvm.org/D35084


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307328 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-06 22:32:27 +00:00
Leo Li
2079d678b5 [ConstantHoisting] Avoid hoisting constants in GEPs that index into a struct type.
Summary:
Indices for GEPs that index into a struct type should always be
constants. This added more checks in `collectConstantCandidates:` which make
sure constants for GEP pointer type are not hoisted.

This fixed Bug https://bugs.llvm.org/show_bug.cgi?id=33538

Reviewers: ributzka, rnk

Reviewed By: ributzka

Subscribers: efriedma, llvm-commits, srhines, javed.absar, pirama

Differential Revision: https://reviews.llvm.org/D34576

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306704 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-29 17:03:34 +00:00
Benjamin Kramer
a0f27f968e Make helper functions static. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304029 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-26 20:09:00 +00:00
Wei Mi
a88bbf0e22 [ConstHoisting] Add BFI in constanthoisting pass and select the best insertion
places based on it.

Existing constant hoisting pass will merge a group of contants in a small range
and hoist the const materialization code to the common dominator of their uses.
However, if the uses are all in cold pathes, existing implementation may hoist
the materialization code from cold pathes to a hot place. This may hurt performance.
The patch introduces BFI to the pass and selects the best insertion places based
on it.

The change is controlled by an option consthoist-with-block-frequency which is
off by default for now.

Differential Revision: https://reviews.llvm.org/D28962


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300989 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-21 15:50:16 +00:00
Reid Kleckner
386f13715a [Constant Hoisting] Avoid inserting instructions before EH pads
Now that terminators can be EH pads, this code needs to iterate over the
immediate dominators of the EH pad to find a valid insertion point.

Fix for PR32107

Patch by Robert Olliff!

Differential Revision: https://reviews.llvm.org/D30511

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296698 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-01 22:41:12 +00:00
Chandler Carruth
10dd00ced5 [PM] Introduce an analysis set used to preserve all analyses over
a function's CFG when that CFG is unchanged.

This allows transformation passes to simply claim they preserve the CFG
and analysis passes to check for the CFG being preserved to remove the
fanout of all analyses being listed in all passes.

I've gone through and removed or cleaned up as many of the comments
reminding us to do this as I could.

Differential Revision: https://reviews.llvm.org/D28627

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292054 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-15 06:32:49 +00:00
Benjamin Kramer
1fb85c6675 Apply clang-tidy's performance-unnecessary-value-param to LLVM.
With some minor manual fixes for using function_ref instead of
std::function. No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291904 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-13 14:39:03 +00:00
Simon Pilgrim
431da84b02 Fix spelling mistakes in Transforms comments. NFC.
Identified by Pedro Giffuni in PR27636.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287488 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-20 13:19:49 +00:00
Mehdi Amini
67f335d992 Use StringRef in Pass/PassManager APIs (NFC)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283004 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-01 02:56:57 +00:00
Sjoerd Meijer
05488db23f This implements a more optimal algorithm for selecting a base constant in
constant hoisting. It not only takes into account the number of uses and the
cost of expressions in which constants appear, but now also the resulting
integer range of the offsets. Thus, the algorithm maximizes the number of uses
within an integer range that will enable more efficient code generation. On
ARM, for example, this will enable code size optimisations because less
negative offsets will be created. Negative offsets/immediates are not supported
by Thumb1 thus preventing more compact instruction encoding.

Differential Revision: http://reviews.llvm.org/D21183



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275382 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-14 07:44:20 +00:00
Michael Kuperstein
3fae04db50 [PM] Port ConstantHoisting to the new Pass Manager
Differential Revision: http://reviews.llvm.org/D21945


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274411 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-02 00:16:47 +00:00
Andrew Kaylor
1e455c5cfb 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



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267231 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-22 22:06:11 +00:00
Vedant Kumar
8866d94a61 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267115 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-22 06:51:37 +00:00
Andrew Kaylor
c852398cbc 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



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267022 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-21 17:58:54 +00:00
Tim Northover
5a4800a05f ARM: override cost function to re-enable ConstantHoisting (& fix it).
At some point, ARM stopped getting any benefit from ConstantHoisting because
the pass called a different variant of getIntImmCost. Reimplementing the
correct variant revealed some problems, however:

  + ConstantHoisting was modifying switch statements. This is simply invalid,
    the cases must remain integer constants no matter the notional cost.
  + ConstantHoisting was mangling alloca instructions in the entry block. These
    should be handled by FrameLowering, so constants actually have a cost of 0.
    Worse, the resulting bitcasts meant they became dynamic allocas.

rdar://25707382

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266260 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-13 23:08:27 +00:00
Duncan P. N. Exon Smith
7e8a22b5c8 Scalar: Remove some implicit ilist iterator conversions, NFC
Remove some of the implicit ilist iterator conversions in
LLVMScalarOpts.  More to go.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250197 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-13 18:26:00 +00:00
David Majnemer
42bf5e9e58 Replace some calls to isa<LandingPadInst> with isEHPad()
No functionality change is intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245487 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-19 19:54:02 +00:00
Alexander Kornienko
cd52a7a381 Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240390 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-23 09:49:53 +00:00
Alexander Kornienko
cf0db29df2 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!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240137 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-19 15:57:42 +00:00
Benjamin Kramer
1bfcd1f675 Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232998 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-23 19:32:43 +00:00
Andrea Di Biagio
47cd120a18 [optnone] Skip pass Constant Hoisting on optnone functions.
Added test CodeGen/X86/constant-hoisting-optnone.ll to verify that
pass Constant Hoisting is not run on optnone functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229258 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-14 15:11:48 +00:00
Chandler Carruth
baceda736e [multiversion] Thread a function argument through all the callers of the
getTTI method used to get an actual TTI object.

No functionality changed. This just threads the argument and ensures
code like the inliner can correctly look up the callee's TTI rather than
using a fixed one.

The next change will use this to implement per-function subtarget usage
by TTI. The changes after that should eliminate the need for FTTI as that
will have become the default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227730 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 12:01:35 +00:00
Chandler Carruth
a6a87b595d [PM] Change the core design of the TTI analysis to use a polymorphic
type erased interface and a single analysis pass rather than an
extremely complex analysis group.

The end result is that the TTI analysis can contain a type erased
implementation that supports the polymorphic TTI interface. We can build
one from a target-specific implementation or from a dummy one in the IR.

I've also factored all of the code into "mix-in"-able base classes,
including CRTP base classes to facilitate calling back up to the most
specialized form when delegating horizontally across the surface. These
aren't as clean as I would like and I'm planning to work on cleaning
some of this up, but I wanted to start by putting into the right form.

There are a number of reasons for this change, and this particular
design. The first and foremost reason is that an analysis group is
complete overkill, and the chaining delegation strategy was so opaque,
confusing, and high overhead that TTI was suffering greatly for it.
Several of the TTI functions had failed to be implemented in all places
because of the chaining-based delegation making there be no checking of
this. A few other functions were implemented with incorrect delegation.
The message to me was very clear working on this -- the delegation and
analysis group structure was too confusing to be useful here.

The other reason of course is that this is *much* more natural fit for
the new pass manager. This will lay the ground work for a type-erased
per-function info object that can look up the correct subtarget and even
cache it.

Yet another benefit is that this will significantly simplify the
interaction of the pass managers and the TargetMachine. See the future
work below.

The downside of this change is that it is very, very verbose. I'm going
to work to improve that, but it is somewhat an implementation necessity
in C++ to do type erasure. =/ I discussed this design really extensively
with Eric and Hal prior to going down this path, and afterward showed
them the result. No one was really thrilled with it, but there doesn't
seem to be a substantially better alternative. Using a base class and
virtual method dispatch would make the code much shorter, but as
discussed in the update to the programmer's manual and elsewhere,
a polymorphic interface feels like the more principled approach even if
this is perhaps the least compelling example of it. ;]

Ultimately, there is still a lot more to be done here, but this was the
huge chunk that I couldn't really split things out of because this was
the interface change to TTI. I've tried to minimize all the other parts
of this. The follow up work should include at least:

1) Improving the TargetMachine interface by having it directly return
   a TTI object. Because we have a non-pass object with value semantics
   and an internal type erasure mechanism, we can narrow the interface
   of the TargetMachine to *just* do what we need: build and return
   a TTI object that we can then insert into the pass pipeline.
2) Make the TTI object be fully specialized for a particular function.
   This will include splitting off a minimal form of it which is
   sufficient for the inliner and the old pass manager.
3) Add a new pass manager analysis which produces TTI objects from the
   target machine for each function. This may actually be done as part
   of #2 in order to use the new analysis to implement #2.
4) Work on narrowing the API between TTI and the targets so that it is
   easier to understand and less verbose to type erase.
5) Work on narrowing the API between TTI and its clients so that it is
   easier to understand and less verbose to forward.
6) Try to improve the CRTP-based delegation. I feel like this code is
   just a bit messy and exacerbating the complexity of implementing
   the TTI in each target.

Many thanks to Eric and Hal for their help here. I ended up blocked on
this somewhat more abruptly than I expected, and so I appreciate getting
it sorted out very quickly.

Differential Revision: http://reviews.llvm.org/D7293

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227669 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-31 03:43:40 +00:00
Benjamin Kramer
dbc6d9b9d7 Remove unnecessary copying or replace it with moves in a bunch of places.
NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219061 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-04 16:55:56 +00:00
NAKAMURA Takumi
38dbc84602 ConstantHoisting.cpp: Add <tuple> for std::tie, since r207593 removed FileSystem.h, it includes <tuple>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207614 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-30 06:44:50 +00:00
Craig Topper
8d7221ccf5 [C++] Use 'nullptr'. Transforms edition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207196 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-25 05:29:35 +00:00
Juergen Ributzka
b95412cc24 [Constant Hoisting] Materialize the constant before the cloned cast instruction.
In the case where the constant comes from a cloned cast instruction, the
materialization code has to go before the cloned cast instruction.

This commit fixes the method that finds the materialization insertion point
by making it aware of this case.

This fixes <rdar://problem/15532441>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206913 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-22 18:06:58 +00:00
Juergen Ributzka
0db2ba1ce8 [Constant Hoisting] Print the instructions in the correct order for debugging. No functional change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206912 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-22 18:06:51 +00:00
Chandler Carruth
7962dbdc65 [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE
definition below all of the header #include lines, lib/Transforms/...
edition.

This one is tricky for two reasons. We again have a couple of passes
that define something else before the includes as well. I've sunk their
name macros with the DEBUG_TYPE.

Also, InstCombine contains headers that need DEBUG_TYPE, so now those
headers #define and #undef DEBUG_TYPE around their code, leaving them
well formed modular headers. Fixing these headers was a large motivation
for all of these changes, as "leaky" macros of this form are hard on the
modules implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206844 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-22 02:55:47 +00:00
Juergen Ributzka
7fce127f62 Revert "[Constant Hoisting] Lazily compute the idom and cache the result."
This code is no longer usefull, because we only compute and use the
IDom once. There is no benefit in caching it anymore.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205498 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-03 01:38:47 +00:00