735 Commits

Author SHA1 Message Date
Nicola Zaghen
9667127c14 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
Adrian Prantl
076a6683eb 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
Nico Weber
fcf0230e34 IWYU for llvm-config.h in llvm, additions.
See r331124 for how I made a list of files missing the include.
I then ran this Python script:

    for f in open('filelist.txt'):
        f = f.strip()
        fl = open(f).readlines()

        found = False
        for i in xrange(len(fl)):
            p = '#include "llvm/'
            if not fl[i].startswith(p):
                continue
            if fl[i][len(p):] > 'Config':
                fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
                found = True
                break
        if not found:
            print 'not found', f
        else:
            open(f, 'w').write(''.join(fl))

and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.

No intended behavior change.

llvm-svn: 331184
2018-04-30 14:59:11 +00:00
Mandeep Singh Grang
4e39759fa1 [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

llvm-svn: 330059
2018-04-13 19:47:57 +00:00
David Blaikie
2efa3f569e Transforms: Introduce Transforms/Utils.h rather than spreading the declarations amongst Scalar.h and IPO.h
Fixes layering - Transforms/Utils shouldn't depend on including a Scalar
or IPO header, because Scalar and IPO depend on Utils.

llvm-svn: 328717
2018-03-28 17:44:36 +00:00
Krzysztof Parzyszek
bd36a69b34 [LSR] Allow giving priority to post-incrementing addressing modes
Implement TTI interface for targets to indicate that the LSR should give
priority to post-incrementing addressing modes.

Combination of patches by Sebastian Pop and Brendon Cahoon.

Differential Revision: https://reviews.llvm.org/D44758

llvm-svn: 328490
2018-03-26 13:10:09 +00:00
David Blaikie
a9b82b5ec4 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.

llvm-svn: 328165
2018-03-21 22:34:23 +00:00
Adam Nemet
daee4e2694 Revert "[LSR] Avoid UB overflow when examining reuse opportunities"
This reverts commit r324943.

Breaking bots, reverting for Gerolf.

llvm-svn: 324958
2018-02-12 22:42:13 +00:00
Gerolf Hoflehner
c74d0ab4e8 [LSR] Avoid UB overflow when examining reuse opportunities
llvm-svn: 324943
2018-02-12 21:49:32 +00:00
Sanjay Patel
a19541c05c [LoopStrengthReduce, x86] don't add cost for a cmp that will be macro-fused (PR35681)
In the motivating case from PR35681 and represented by the macro-fuse-cmp test:
https://bugs.llvm.org/show_bug.cgi?id=35681
...there's a 37 -> 31 byte size win for the loop because we eliminate the big base 
address offsets.

SPEC2017 on Ryzen shows no significant perf difference.

Differential Revision: https://reviews.llvm.org/D42607

llvm-svn: 324289
2018-02-05 23:43:05 +00:00
Mikael Holmen
a7c9ce5fb8 [LSR] Don't force bases of foldable formulae to the final type.
Summary:
Before emitting code for scaled registers, we prevent
SCEVExpander from hoisting any scaled addressing mode
by emitting all the bases first. However, these bases
are being forced to the final type, resulting in some
odd code.

For example, if the type of the base is an integer and
the final type is a pointer, we will emit an inttoptr
for the base, a ptrtoint for the scale, and then a
'reverse' GEP where the GEP pointer is actually the base
integer and the index is the pointer. It's more intuitive
to use the pointer as a pointer and the integer as index.

Patch by: Bevin Hansson

Reviewers: atrick, qcolombet, sanjoy

Reviewed By: qcolombet

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42103

llvm-svn: 323946
2018-02-01 06:38:34 +00:00
Javed Absar
818c79d173 [SCEV] Fix typo. NFC.
Fix confusing typo in comment.

llvm-svn: 322765
2018-01-17 21:58:35 +00:00
Javed Absar
3e355c5363 [SCEV] fix typo
llvm-svn: 322629
2018-01-17 11:03:06 +00:00
Benjamin Kramer
32a4f8ce12 Use phi ranges to simplify code. No functionality change intended.
llvm-svn: 321585
2017-12-30 15:27:33 +00:00
Matt Arsenault
b1cb514280 LSR: Check more intrinsic pointer operands
llvm-svn: 320424
2017-12-11 21:38:43 +00:00
Jatin Bhateja
b020a5ea70 [SCEV] Handling for ICmp occuring in the evolution chain.
Summary:
 If a compare instruction is same or inverse of the compare in the
 branch of the loop latch, then return a constant evolution node.
 This shall facilitate computations of loop exit counts in cases
 where compare appears in the evolution chain of induction variables.

 Will fix PR 34538

Reviewers: sanjoy, hfinkel, junryoungju

Reviewed By: sanjoy, junryoungju

Subscribers: javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D38494

llvm-svn: 318050
2017-11-13 16:43:24 +00:00
Vedant Kumar
cb217682a0 [LSR] Clarify a comment. NFC.
llvm-svn: 317295
2017-11-03 01:01:28 +00:00
Sanjoy Das
d41e33114f Revert "[ScalarEvolution] Handling for ICmp occuring in the evolution chain."
This reverts commit r316054.  There was some confusion over the review process:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20171016/495884.html

llvm-svn: 316129
2017-10-18 22:00:57 +00:00
Eugene Zelenko
74914fb100 [Transforms] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 316128
2017-10-18 21:46:47 +00:00
Jatin Bhateja
02e129e082 [ScalarEvolution] Handling for ICmp occuring in the evolution chain.
Summary:
 If a compare instruction is same or inverse of the compare in the
 branch of the loop latch, then return a constant evolution node.
 Currently scope of evaluation is limited to SCEV computation for
 PHI nodes.

 This shall facilitate computations of loop exit counts in cases
 where compare appears in the evolution chain of induction variables.

 Will fix PR 34538
Reviewers: sanjoy, hfinkel, junryoungju

Reviewed By: junryoungju

Subscribers: javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D38494

llvm-svn: 316054
2017-10-18 01:36:16 +00:00
Aaron Ballman
1dbcb12601 Reverting r315590; it did not include changes for llvm-tblgen, which is causing link errors for several people.
Error LNK2019 unresolved external symbol "public: void __cdecl `anonymous namespace'::MatchableInfo::dump(void)const " (?dump@MatchableInfo@?A0xf4f1c304@@QEBAXXZ) referenced in function "public: void __cdecl `anonymous namespace'::AsmMatcherEmitter::run(class llvm::raw_ostream &)" (?run@AsmMatcherEmitter@?A0xf4f1c304@@QEAAXAEAVraw_ostream@llvm@@@Z) llvm-tblgen D:\llvm\2017\utils\TableGen\AsmMatcherEmitter.obj 1

llvm-svn: 315854
2017-10-15 14:32:27 +00:00
Don Hinton
16622c817e [dump] Remove NDEBUG from test to enable dump methods [NFC]
Summary:
Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with
LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP.

Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods.

Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so
it'll be picked up by public headers.

Differential Revision: https://reviews.llvm.org/D38406

llvm-svn: 315590
2017-10-12 16:16:06 +00:00
Max Kazantsev
4e5297ed76 [LSR] Fix Shadow IV in case of integer overflow
When LSR processes code like

  int accumulator = 0;
  for (int i = 0; i < N; i++) {
    accummulator += i;
    use((double) accummulator);
  }

It may decide to replace integer `accumulator` with a double Shadow IV to get rid
of casts.  The problem with that is that the `accumulator`'s value may overflow.
Starting from this moment, the behavior of integer and double accumulators
will differ.

This patch strenghtens up the conditions of Shadow IV mechanism applicability.
We only allow it for IVs that are proved to be `AddRec`s with `nsw`/`nuw` flag.

Differential Revision: https://reviews.llvm.org/D37209

llvm-svn: 311986
2017-08-29 07:32:20 +00:00
Jonas Paulsson
54a000e514 [LSR / TTI / SystemZ] Eliminate TargetTransformInfo::isFoldableMemAccess()
isLegalAddressingMode() has recently gained the extra optional Instruction*
parameter, and therefore it can now do the job that previously only
isFoldableMemAccess() could do.

The SystemZ implementation of isLegalAddressingMode() has gained the
functionality of checking for offsets, which used to be done with
isFoldableMemAccess().

The isFoldableMemAccess() hook has been removed everywhere.

Review: Quentin Colombet, Ulrich Weigand
https://reviews.llvm.org/D35933

llvm-svn: 310463
2017-08-09 11:28:01 +00:00
Jonas Paulsson
b5dbc00a27 [LoopStrengthReduce] Don't neglect the Fixup.Offset in isAMCompletelyFolded().
In the recursive call to isAMCompletelyFolded(), the passed offset should be
the sum of F.BaseOffset and Fixup.Offset.

Review: Quentin Colombet.
llvm-svn: 310462
2017-08-09 11:27:46 +00:00
Evgeny Stupachenko
8c60bbb9d2 Reapply fix PR23384 (part 3 of 3) r304824 (was reverted in r305720).
The root cause of reverting was fixed - PR33514.

Summary:
The patch makes instruction count the highest priority for
 LSR solution for X86 (previously registers had highest priority).

Reviewers: qcolombet

Differential Revision: http://reviews.llvm.org/D30562

From: Evgeny Stupachenko <evstupac@gmail.com>
                         <evgeny.v.stupachenko@intel.com>
llvm-svn: 310289
2017-08-07 19:56:34 +00:00
Evgeny Stupachenko
2be9c5c55b Fix PR33514
Summary:
The bug was uncovered after fix of  PR23384 (part 3 of 3).
The patch restricts pointer multiplication in SCEV computaion for ICmpZero.

Reviewers: qcolombet

Differential Revision: http://reviews.llvm.org/D36170

From: Evgeny Stupachenko <evstupac@gmail.com>
                         <evgeny.v.stupachenko@intel.com>
llvm-svn: 310092
2017-08-04 18:46:13 +00:00
Florian Hahn
f80450c0bb Extend ifdefs to more unused helper functions.
This fixes a buildbot failure with -Werror introduced by r309553

llvm-svn: 309572
2017-07-31 16:11:43 +00:00
Florian Hahn
3d431b22ac Guard print() functions only used by dump() functions.
Summary:
Since  r293359, most dump() function are only defined when
`!defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)` holds. print() functions
only used by dump() functions are now unused in release builds,
generating lots of warnings. This patch only defines some print()
functions if they are used.

Reviewers: MatzeB

Reviewed By: MatzeB

Subscribers: arsenm, mzolotukhin, nhaehnle, llvm-commits

Differential Revision: https://reviews.llvm.org/D35949

llvm-svn: 309553
2017-07-31 10:07:49 +00:00
Jonas Paulsson
c38a4eb7d4 [SystemZ, LoopStrengthReduce]
This patch makes LSR generate better code for SystemZ in the cases of memory
intrinsics, Load->Store pairs or comparison of immediate with memory.

In order to achieve this, the following common code changes were made:

 * New TTI hook: LSRWithInstrQueries(), which defaults to false. Controls if
 LSR should do instruction-based addressing evaluations by calling
 isLegalAddressingMode() with the Instruction pointers.
 * In LoopStrengthReduce: handle address operands of memset, memmove and memcpy
 as address uses, and call isFoldableMemAccessOffset() for any LSRUse::Address,
 not just loads or stores.

SystemZ changes:

 * isLSRCostLess() implemented with Insns first, and without ImmCost.
 * New function supportedAddressingMode() that is a helper for TTI methods
 looking at Instructions passed via pointers.

Review: Ulrich Weigand, Quentin Colombet
https://reviews.llvm.org/D35262
https://reviews.llvm.org/D35049

llvm-svn: 308729
2017-07-21 11:59:37 +00:00
Craig Topper
d8ebaac997 [Constants] If we already have a ConstantInt*, prefer to use isZero/isOne/isMinusOne instead of isNullValue/isOneValue/isAllOnesValue inherited from Constant. NFCI
Going through the Constant methods requires redetermining that the Constant is a ConstantInt and then calling isZero/isOne/isMinusOne.

llvm-svn: 307292
2017-07-06 18:39:47 +00:00
Wei Mi
279c30993a [LSR] Narrow search space by filtering non-optimal formulae with the same ScaledReg and Scale.
When the formulae search space is huge, LSR uses a series of heuristic to keep
pruning the search space until the number of possible solutions are within
certain limit.

The big hammer of the series of heuristics is NarrowSearchSpaceByPickingWinnerRegs,
which picks the register which is used by the most LSRUses and deletes the other
formulae which don't use the register. This is a effective way to prune the search
space, but quite often not a good way to keep the best solution. We saw cases before
that the heuristic pruned the best formula candidate out of search space.

To relieve the problem, we introduce a new heuristic called
NarrowSearchSpaceByFilterFormulaWithSameScaledReg. The basic idea is in order to
reduce the search space while keeping the best formula, we want to keep as many
formulae with different Scale and ScaledReg as possible. That is because the central
idea of LSR is to choose a group of loop induction variables and use those induction
variables to represent LSRUses. An induction variable candidate is often represented
by the Scale and ScaledReg in a formula. If we have more formulae with different
ScaledReg and Scale to choose, we have better opportunity to find the best solution.
That is why we believe pruning search space by only keeping the best formula with the
same Scale and ScaledReg should be more effective than PickingWinnerReg. And we use
two criteria to choose the best formula with the same Scale and ScaledReg. The first
criteria is to select the formula using less non shared registers, and the second
criteria is to select the formula with less cost got from RateFormula. The patch
implements the heuristic before NarrowSearchSpaceByPickingWinnerRegs, which is the
last resort.

Testing shows we get 1.8% and 2% on two internal benchmarks on x86. llvm nightly
testsuite performance is neutral. We also tried lsr-exp-narrow and it didn't help
on the two improved internal cases we saw.

Differential Revision: https://reviews.llvm.org/D34583

llvm-svn: 307269
2017-07-06 15:52:14 +00:00
Hans Wennborg
901a9b880c Revert r304824 "Fix PR23384 (part 3 of 3)"
This seems to be interacting badly with ASan somehow, causing false reports of
heap-buffer overflows: PR33514.

> Summary:
> The patch makes instruction count the highest priority for
> LSR solution for X86 (previously registers had highest priority).
>
> Reviewers: qcolombet
>
> Differential Revision: http://reviews.llvm.org/D30562
>
> From: Evgeny Stupachenko <evstupac@gmail.com>

llvm-svn: 305720
2017-06-19 17:57:15 +00:00
Evgeny Stupachenko
5f498de20b Fix PR23384 (part 3 of 3)
Summary:
The patch makes instruction count the highest priority for
 LSR solution for X86 (previously registers had highest priority).

Reviewers: qcolombet

Differential Revision: http://reviews.llvm.org/D30562

From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 304824
2017-06-06 20:04:16 +00:00
Evgeny Stupachenko
5e8ec36407 Fix PR23384 (part 2 of 3) NFC
Summary:
The patch moves LSR cost comparison to target part.

Reviewers: qcolombet

Differential Revision: http://reviews.llvm.org/D30561

From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 304750
2017-06-05 23:37:00 +00:00
Evgeny Stupachenko
7b4ea0cb59 LSR: Calculate instruction cost only if InsnsCost is set to true (NFC)
Summary:

The patch guard all instruction cost calculations with InsnCosts (-lsr-insns-cost) option.
Currently even if the option set to false we calculate and print (in debug mode) instruction costs.

Reviewers: qcolombet

Differential Revision: http://reviews.llvm.org/D33914

From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 304746
2017-06-05 22:44:18 +00:00
Wei Mi
cb3d209c15 [LSR] Call canonicalize after we generate a new Formula in GenerateTruncates. Fix PR33077.
The testcase in PR33077 generates a LSR Use Formula with two SCEVAddRecExprs for the same
loop. Such uncommon formula will become non-canonical after GenerateTruncates adds sign
extension to the ScaledReg of the Formula, and it will break the assertion that every
Formula to be inserted is canonical.

The fix is to call canonicalize for the raw Formula generated by GenerateTruncates
before inserting it.

llvm-svn: 303361
2017-05-18 17:21:22 +00:00
Francis Visoiu Mistrih
d02a2cc569 BitVector: add iterators for set bits
Differential revision: https://reviews.llvm.org/D32060

llvm-svn: 303227
2017-05-17 01:07:53 +00:00
Sanjoy Das
19757d9ec3 Rename WeakVH to WeakTrackingVH; NFC
This relands r301424.

llvm-svn: 301812
2017-05-01 17:07:49 +00:00
Sanjoy Das
732f091d68 Reverts commit r301424, r301425 and r301426
Commits were:

"Use WeakVH instead of WeakTrackingVH in AliasSetTracker's UnkownInsts"
"Add a new WeakVH value handle; NFC"
"Rename WeakVH to WeakTrackingVH; NFC"

The changes assumed pointers are 8 byte aligned on all architectures.

llvm-svn: 301429
2017-04-26 16:37:05 +00:00
Sanjoy Das
e226969b1c Rename WeakVH to WeakTrackingVH; NFC
Summary:
I plan to use WeakVH to mean "nulls itself out on deletion, but does
not track RAUW" in a subsequent commit.

Reviewers: dblaikie, davide

Reviewed By: davide

Subscribers: arsenm, mehdi_amini, mcrosier, mzolotukhin, jfb, llvm-commits, nhaehnle

Differential Revision: https://reviews.llvm.org/D32266

llvm-svn: 301424
2017-04-26 16:20:52 +00:00
Sanjoy Das
b2e0a6b244 Tighten the API for ScalarEvolutionNormalization
llvm-svn: 300331
2017-04-14 15:49:59 +00:00
Sanjoy Das
fdafc30cdf Remove NormalizeAutodetect; NFC
It is cleaner to have a callback based system where the logic of
whether an add recurrence is normalized or not lives on IVUsers.

This is one step in a multi-step cleanup.

llvm-svn: 300330
2017-04-14 15:49:53 +00:00
Evgeny Stupachenko
e5edb8e9bf Set option enabling LSR alternative way to resolve complex solution to false.
Differential Revision: http://reviews.llvm.org/D29862

From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 296959
2017-03-04 03:14:05 +00:00
Wei Mi
ce97f6bd94 [LSR] Canonicalize formula and put recursive Reg related with current loop in ScaledReg.
After rL294814, LSR formula can have multiple SCEVAddRecExprs inside of its BaseRegs.
Previous canonicalization will swap the first SCEVAddRecExpr in BaseRegs with ScaledReg.
But now we want to swap the SCEVAddRecExpr Reg related with current loop with ScaledReg.
Otherwise, we may generate code like this: RegA + lsr.iv + RegB, where loop invariant
parts RegA and RegB are not grouped together and cannot be promoted outside of loop.
With this patch, it will ensure lsr.iv to be generated later in the expr:
RegA + RegB + lsr.iv, so that RegA + RegB can be promoted outside of loop.

Differential Revision: https://reviews.llvm.org/D26781

llvm-svn: 295884
2017-02-22 21:47:08 +00:00
Evgeny Stupachenko
9cbd2687bb The patch introduces new way of narrowing complex (>UINT16 variants) solutions.
The new method introduced under "-lsr-exp-narrow" option (currenlty set to true).

Summary:

The method is based on registers number mathematical expectation and should be
 generally closer to optimal solution.
Please see details in comments to
 "LSRInstance::NarrowSearchSpaceByDeletingCostlyFormulas()" function
 (in lib/Transforms/Scalar/LoopStrengthReduce.cpp).

Reviewers: qcolombet

Differential Revision: http://reviews.llvm.org/D29862

From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 295704
2017-02-21 07:34:40 +00:00
Wei Mi
a5fbb85795 [LSR] Prevent formula with SCEVAddRecExpr type of Reg from Sibling loops
In rL294814, we allow formula with SCEVAddRecExpr type of Reg from loops
other than current loop. This is good for the case when induction variable
of outerloop being used in expr in innerloop. But it is very bad to allow
such Reg from sibling loop because we may need to add lsr.iv in other sibling
loops when scev expanding those SCEVAddRecExpr type exprs. For the testcase
below, one loop can be inserted with a bunch of lsr.iv because of LSR for
other loops. 

// The induction variable j from a loop in the middle will have initial
// value generated from previous sibling loop and exit value used by its
// next sibling loop.
void goo(long i, long j); 
long cond; 

void foo(long N) { 
long i = 0; 
long j = 0; 
i = 0; do { goo(i, j); i++; j++; } while (cond); 
i = 0; do { goo(i, j); i++; j++; } while (cond); 
i = 0; do { goo(i, j); i++; j++; } while (cond); 
i = 0; do { goo(i, j); i++; j++; } while (cond); 
i = 0; do { goo(i, j); i++; j++; } while (cond); 
i = 0; do { goo(i, j); i++; j++; } while (cond); 
} 

The fix is to only allow formula with SCEVAddRecExpr type of Reg from current
loop or its parents.

Differential Revision: https://reviews.llvm.org/D30021

llvm-svn: 295378
2017-02-16 21:27:31 +00:00
Mikael Holmen
b41e5c8bc7 [LSR] Pointers with different address spaces are considered incompatible.
Summary:
Function isCompatibleIVType is already used as a guard before the call to

 SE.getMinusSCEV(OperExpr, PrevExpr);

in LSRInstance::ChainInstruction. getMinusSCEV requires the expressions
to be of the same type, so we now consider two pointers with different
address spaces to be incompatible, since it is possible that the pointers
in fact have different sizes.

Reviewers: qcolombet, eli.friedman

Reviewed By: qcolombet

Subscribers: nhaehnle, Ka-Ka, llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D29885

llvm-svn: 295033
2017-02-14 06:37:42 +00:00
Evgeny Stupachenko
3bbd6ed985 Fix PR23384 (under "-lsr-insns-cost" option)
Summary:
The patch adds instructions number generated by a solution
 to LSR cost under "-lsr-insns-cost" option.

Reviewers: qcolombet, hfinkel

Differential Revision: http://reviews.llvm.org/D28307

From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 294821
2017-02-11 02:57:43 +00:00
Wei Mi
4f28dc3b0c [LSR] Recommit: Allow formula containing Reg for SCEVAddRecExpr related with outerloop.
The recommit includes some changes of testcases. No functional change to the patch.

In RateRegister of existing LSR, if a formula contains a Reg which is a SCEVAddRecExpr,
and this SCEVAddRecExpr's loop is an outerloop, the formula will be marked as Loser
and dropped.

Suppose we have an IR that %for.body is outerloop and %for.body2 is innerloop. LSR only
handle inner loop now so only %for.body2 will be handled.

Using the logic above, formula like
reg(%array) + reg({1,+, %size}<%for.body>) + 1*reg({0,+,1}<%for.body2>) will be dropped
no matter what because reg({1,+, %size}<%for.body>) is a SCEVAddRecExpr type reg related
with outerloop. Only formula like
reg(%array) + 1*reg({{1,+, %size}<%for.body>,+,1}<nuw><nsw><%for.body2>) will be kept
because the SCEVAddRecExpr related with outerloop is folded into the initial value of the
SCEVAddRecExpr related with current loop.

But in some cases, we do need to share the basic induction variable
reg{0 ,+, 1}<%for.body2> among LSR Uses to reduce the final total number of induction
variables used by LSR, so we don't want to drop the formula like
reg(%array) + reg({1,+, %size}<%for.body>) + 1*reg({0,+,1}<%for.body2>) unconditionally.

From the existing comment, it tries to avoid considering multiple level loops at the same time.
However, existing LSR only handles innermost loop, so for any SCEVAddRecExpr with a loop other
than current loop, it is an invariant and will be simple to handle, and the formula doesn't have
to be dropped.

Differential Revision: https://reviews.llvm.org/D26429

llvm-svn: 294814
2017-02-11 00:50:23 +00:00