Commit Graph

1016 Commits

Author SHA1 Message Date
Wei Mi 481232e991 Fix test/Analysis/ScalarEvolution/scev-expander-existing-value-offset.ll for rL276136.
The content in this testcase was accidentally duplicated. Fix the error.

llvm-svn: 276139
2016-07-20 16:54:58 +00:00
Wei Mi db80c0c77f Use ValueOffsetPair to enhance value reuse during SCEV expansion.
In D12090, the ExprValueMap was added to reuse existing value during SCEV expansion.
However, const folding and sext/zext distribution can make the reuse still difficult.

A simplified case is: suppose we know S1 expands to V1 in ExprValueMap, and
  S1 = S2 + C_a
  S3 = S2 + C_b
where C_a and C_b are different SCEVConstants. Then we'd like to expand S3 as
V1 - C_a + C_b instead of expanding S2 literally. It is helpful when S2 is a
complex SCEV expr and S2 has no entry in ExprValueMap, which is usually caused
by the fact that S3 is generated from S1 after const folding.

In order to do that, we represent ExprValueMap as a mapping from SCEV to
ValueOffsetPair. We will save both S1->{V1, 0} and S2->{V1, C_a} into the
ExprValueMap when we create SCEV for V1. When S3 is expanded, it will first
expand S2 to V1 - C_a because of S2->{V1, C_a} in the map, then expand S3 to
V1 - C_a + C_b.

Differential Revision: https://reviews.llvm.org/D21313

llvm-svn: 276136
2016-07-20 16:40:33 +00:00
Simon Pilgrim 1b4f511aaa [X86][SSE] Add cost model values for CTPOP of vectors
This patch adds costs for the vectorized implementations of CTPOP, the default values were seriously underestimating the cost of these and was encouraging vectorization on targets where serialized use of POPCNT would be much better.

Differential Revision: https://reviews.llvm.org/D22456

llvm-svn: 276104
2016-07-20 10:41:28 +00:00
George Burgess IV 8b85321bae [CFLAA] Make a test tell the truth. NFC.
Dishonesty noted by Jia Chen.

llvm-svn: 276028
2016-07-19 20:56:41 +00:00
George Burgess IV 3b059841ff [CFLAA] Add some interproc. analysis to CFLAnders.
This patch adds function summary support to CFLAnders. It also comes
with a lot of tests! Woohoo!

Patch by Jia Chen.

Differential Revision: https://reviews.llvm.org/D22450

llvm-svn: 276026
2016-07-19 20:47:15 +00:00
Simon Pilgrim 47638635cc [X86] Add CTPOP/CTLZ/CTTZ scalar cost tests
llvm-svn: 275725
2016-07-17 18:29:19 +00:00
George Burgess IV 22682e293b [CFLAA] Add attributes handling for CFLAnders.
This patch adds proper handling of stratified attributes into our
anders-style CFLAA implementation. It also comes bundled with more
CFLAnders tests. :)

Patch by Jia Chen.

Differential Revision: https://reviews.llvm.org/D22325

llvm-svn: 275604
2016-07-15 20:02:49 +00:00
George Burgess IV 6d30aa03a0 [CFLAA] Add an initial CFLAnders implementation.
This adds an incomplete anders-style implementation for CFLAA. It's
incomplete in that it's missing interprocedural analysis, attrs
handling, etc. and that it needs more tests. More tests and features
will be added in future commits.

Patch by Jia Chen.

Differential Revision: https://reviews.llvm.org/D22291

llvm-svn: 275602
2016-07-15 19:53:25 +00:00
Tom Stellard 1b5cf6217e GlobalsAA: Functions with the argmemonly attribute won't read arbitrary globals
Summary:
In preparation for changing GlobalsAA to stop assuming that intrinsics
can't read arbitrary globals, we need to make sure GlobalsAA is querying
function attributes rather than relying on this assumption.

This patch was inspired by: http://reviews.llvm.org/D20206

Reviewers: jmolloy, hfinkel

Subscribers: eli.friedman, llvm-commits

Differential Revision: https://reviews.llvm.org/D21318

llvm-svn: 275433
2016-07-14 15:50:27 +00:00
Adam Nemet c2f791d8a7 [BFI] Add new LazyBFI analysis pass
Summary:
This is necessary for D21771.  In order to add the hotness attribute to
optimization remarks we need BFI to be available in all passes that emit
optimization remarks.

However we don't want to pay for computing BFI unless the hotness
attribute is requested.

This is achieved by making BFI lazy at the very high-level through a new
analysis pass -- BFI is not calculated unless requested.

I am adding a test to check the laziness under D21771 where the first
user of the analysis is added.

Reviewers: hfinkel, dexonsmith, davidxl

Subscribers: davidxl, dexonsmith, llvm-commits

Differential Revision: http://reviews.llvm.org/D22141

llvm-svn: 275250
2016-07-13 05:01:48 +00:00
Keno Fischer 1efc3b70c5 Fix ScalarEvolutionExpander step scaling bug
The expandAddRecExprLiterally function incorrectly transforms
`[Start + Step * X]` into `Step * [Start + X]` instead of the correct
transform of `[Step * X] + Start`.

This caused https://github.com/JuliaLang/julia/issues/14704#issuecomment-174126219
due to what appeared to be sufficiently complicated loop interactions.

Patch by Jameson Nash (jameson@juliacomputing.com).

Reviewers: sanjoy
Differential Revision: http://reviews.llvm.org/D16505

llvm-svn: 275239
2016-07-13 01:28:12 +00:00
Michael Kuperstein f0c59330e9 [X86] Make some cast costs more precise
Make some AVX and AVX512 cast costs more precise.
Based on part of a patch by Elena Demikhovsky (D15604).

Differential Revision: http://reviews.llvm.org/D22064

llvm-svn: 275106
2016-07-11 21:39:44 +00:00
Hal Finkel bf3957a553 Teach isDereferenceablePointer to look through returned-argument functions
For functions which are known to return their argument,
isDereferenceableAndAlignedPointer can examine the argument value.

Differential Revision: http://reviews.llvm.org/D9384

llvm-svn: 275038
2016-07-11 03:08:49 +00:00
Hal Finkel e186debb8b Teach SCEV to look through returned-argument functions
When building SCEVs, if a function is known to return its argument, then we can
build the SCEV using the corresponding argument value.

Differential Revision: http://reviews.llvm.org/D9381

llvm-svn: 275037
2016-07-11 02:48:23 +00:00
Hal Finkel 5c12d8fe8f BasicAA should look through functions with returned arguments
Motivated by the work on the llvm.noalias intrinsic, teach BasicAA to look
through returned-argument functions when answering queries. This is essential
so that we don't loose all other AA information when supplementing with
llvm.noalias.

Differential Revision: http://reviews.llvm.org/D9383

llvm-svn: 275035
2016-07-11 01:32:20 +00:00
Adam Nemet f836067cc0 [LAA] Port test to the new PM
This is a follow-on to r274452.

The LAA with the new PM is a loop pass so we go from inner to outer loops.

Also using a CHECK-NOT didn't make much sense because we print something
in either case; whether an invariant is 'found' or 'not found'.

llvm-svn: 274935
2016-07-08 21:24:06 +00:00
Justin Bogner a466cc33fa NVPTX: Remove the legacy ptx intrinsics
- Rename the ptx.read.* intrinsics to nvvm.read.ptx.sreg.* - some but
  not all of these registers were already accessible via the nvvm
  name.
- Rename ptx.bar.sync nvvm.bar.sync, to match nvvm.bar0.

There's a fair amount of code motion here, but it's all very
mechanical.

llvm-svn: 274769
2016-07-07 16:40:17 +00:00
Sean Silva 284b0324e2 [PM] Avoid getResult on a higher level in LoopAccessAnalysis
Note that require<domtree> and require<loops> aren't needed because they
come in implicitly via the loop pass manager.

llvm-svn: 274712
2016-07-07 01:01:53 +00:00
Sanjay Patel 04b3496d9b [x86] fix cost of SINT_TO_FP for i32 --> float (PR21356, PR28434)
This is "cvtdq2ps" which does not appear to be particularly slow on any CPU
according to Agner's tables. Choosing "5" as a cost here as suggested in:
https://llvm.org/bugs/show_bug.cgi?id=21356
...but it seems very conservative given that the instruction is fully pipelined,
and I think these costs are supposed to model throughput.

Note that related costs are also most likely too high, but this fixes PR21356
and partly fixes PR28434.

llvm-svn: 274658
2016-07-06 19:15:54 +00:00
Michael Kuperstein aa71bdd3af [TTI] The cost model should not assume vector casts get completely scalarized
The cost model should not assume vector casts get completely scalarized, since
on targets that have vector support, the common case is a partial split up to
the legal vector size. So, when a vector cast  gets split, the resulting casts
end up legal and cheap.

Instead of pessimistically assuming scalarization, base TTI can use the costs
the concrete TTI provides for the split vector, plus a fudge factor to account
for the cost of the split itself. This fudge factor is currently 1 by default,
except on AMDGPU where inserts and extracts are considered free.

Differential Revision: http://reviews.llvm.org/D21251

llvm-svn: 274642
2016-07-06 17:30:56 +00:00
George Burgess IV bfa401e5ad [CFLAA] Split into Anders+Steens analysis.
StratifiedSets (as implemented) is very fast, but its accuracy is also
limited. If we take a more aggressive andersens-like approach, we can be
way more accurate, but we'll also end up being slower.

So, we've decided to split CFLAA into CFLSteensAA and CFLAndersAA.

Long-term, we want to end up in a place where CFLSteens is queried
first; if it can provide an answer, great (since queries are basically
map lookups). Otherwise, we'll fall back to CFLAnders, BasicAA, etc.

This patch splits everything out so we can try to do something like
that when we get a reasonable CFLAnders implementation.

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21910

llvm-svn: 274589
2016-07-06 00:26:41 +00:00
Nemanja Ivanovic 44513e545f [PowerPC] - Legalize vector types by widening instead of integer promotion
This patch corresponds to review:
http://reviews.llvm.org/D20443

It changes the legalization strategy for illegal vector types from integer
promotion to widening. This only applies for vectors with elements of width
that is a multiple of a byte since we have hardware support for vectors with
1, 2, 3, 8 and 16 byte elements.
Integer promotion for vectors is quite expensive on PPC due to the sequence
of breaking apart the vector, extending the elements and reconstituting the
vector. Two of these operations are expensive.
This patch causes between minor and major improvements in performance on most
benchmarks. There are very few benchmarks whose performance regresses. These
regressions can be handled in a subsequent patch with a DAG combine (similar
to how this patch handles int -> fp conversions of illegal vector types).

llvm-svn: 274535
2016-07-05 09:22:29 +00:00
Nicolai Haehnle 84c9f9919a Add writeonly IR attribute
Summary:
This complements the earlier addition of IntrWriteMem and IntrWriteArgMem
LLVM intrinsic properties, see D18291.

Also start using the attribute for memset, memcpy, and memmove intrinsics,
and remove their special-casing in BasicAliasAnalysis.

Reviewers: reames, joker.eph

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D18714

llvm-svn: 274485
2016-07-04 08:01:29 +00:00
Xinliang David Li 8a021317a2 [PM] Port LoopAccessInfo analysis to new PM
It is implemented as a LoopAnalysis pass as 
discussed and agreed upon.

llvm-svn: 274452
2016-07-02 21:18:40 +00:00
Sanjoy Das 0da2d14766 [SCEV] Compute max be count from shift operator only if all else fails
In particular, check to see if we can compute a precise trip count by
exhaustively simulating the loop first.

llvm-svn: 274199
2016-06-30 02:47:28 +00:00
George Burgess IV d86e38e1db [CFLAA] Add support for ModRef queries.
This patch makes CFLAA answer some ModRef queries. Because we don't
distinguish between reading/writing when making StratifiedSets, we're
unable to offer any of the readonly-related answers.

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21858

llvm-svn: 274197
2016-06-30 02:11:26 +00:00
Artur Pilipenko 7ad95ec22d Support arbitrary addrspace pointers in masked load/store intrinsics
This is a resubmittion of 263158 change after fixing the existing problem with intrinsics mangling (see LTO and intrinsics mangling llvm-dev thread for details).

This patch fixes the problem which occurs when loop-vectorize tries to use @llvm.masked.load/store intrinsic for a non-default addrspace pointer. It fails with "Calling a function with a bad signature!" assertion in CallInst constructor because it tries to pass a non-default addrspace pointer to the pointer argument which has default addrspace.

The fix is to add pointer type as another overloaded type to @llvm.masked.load/store intrinsics.

Reviewed By: reames

Differential Revision: http://reviews.llvm.org/D17270

llvm-svn: 274043
2016-06-28 18:27:25 +00:00
Artur Pilipenko 72f76b8805 Revert -r273892 "Support arbitrary addrspace pointers in masked load/store intrinsics" since some of the clang tests don't expect to see the updated signatures.
llvm-svn: 273895
2016-06-27 16:54:33 +00:00
Artur Pilipenko a36aa41519 Support arbitrary addrspace pointers in masked load/store intrinsics
This is a resubmittion of 263158 change after fixing the existing problem with intrinsics mangling (see LTO and intrinsics mangling llvm-dev thread for details).

This patch fixes the problem which occurs when loop-vectorize tries to use @llvm.masked.load/store intrinsic for a non-default addrspace pointer. It fails with "Calling a function with a bad signature!" assertion in CallInst constructor because it tries to pass a non-default addrspace pointer to the pointer argument which has default addrspace.

The fix is to add pointer type as another overloaded type to @llvm.masked.load/store intrinsics.

Reviewed By: reames

Differential Revision: http://reviews.llvm.org/D17270

llvm-svn: 273892
2016-06-27 16:29:26 +00:00
George Burgess IV a3d62be733 [CFLAA] Propagate StratifiedAttrs in interproc. analysis.
This patch also has a refactor that kills StratifiedAttr, and leaves us
with StratifiedAttrs, because having both was mildly redundant.

This patch makes us correctly handle stratified attributes when doing
interprocedural analysis. It also adds another attribute, AttrCaller,
which acts like AttrUnknown. We can filter out AttrCaller values when
during interprocedural analysis, since the caller should have
information about what arguments it's passing to its callee.

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21645

llvm-svn: 273636
2016-06-24 01:00:03 +00:00
George Burgess IV 1f99da54c2 [CFLAA] Use better interprocedural function summaries.
Previously, we just unified any arguments that seemed to be related to
each other. With this patch, we now respect dereference levels, etc.
which should make us substantially more accurate. Proper handling of
StratifiedAttrs will be done in a later patch.

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21536

llvm-svn: 273596
2016-06-23 18:55:23 +00:00
Michael Kuperstein 78028b84d2 [X86] Make arithmetic operations cost model test saner. NFC.
llvm-svn: 273316
2016-06-21 20:41:40 +00:00
George Burgess IV 9fdbfe17a8 [CFLAA] Be more aggressive with interprocedural analysis.
This patch makes us perform interprocedural analysis on functions that
don't have internal linkage. It also removes a test that should've been
deleted in an earlier commit (since other tests now cover everything
that the newly-removed test covers).

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21513

llvm-svn: 273229
2016-06-21 01:42:47 +00:00
George Burgess IV 87b2e41416 [CFLAA] Add interprocedural function summaries.
This patch adds function summaries, so that we don't need to recompute
various properties about function parameters/return values at each
callsite of a function. It also adds many interprocedural tests for
CFLAA.

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21475#inline-182390

llvm-svn: 273219
2016-06-20 23:10:56 +00:00
Simon Pilgrim 356e823b51 [X86][SSE] Add cost model for BSWAP of vectors
The BSWAP of vector types is quite efficiently implemented using vector shuffles on SSE/AVX targets, we should reflect the typical cost of this to encourage vectorization.

Differential Revision: http://reviews.llvm.org/D21521

llvm-svn: 273217
2016-06-20 23:08:21 +00:00
Sanjoy Das e8fd9561cb [SCEV] Fix incorrect trip count computation
The way we elide max expressions when computing trip counts is incorrect
-- it breaks cases like this:

```
static int wrapping_add(int a, int b) {
  return (int)((unsigned)a + (unsigned)b);
}

void test() {
  volatile int end_buf = 2147483548; // INT_MIN - 100
  int end = end_buf;

  unsigned counter = 0;
  for (int start = wrapping_add(end,  200); start < end; start++)
    counter++;

  print(counter);
}
```

Note: the `NoWrap` variable that was being tested has little to do with
the values flowing into the max expression; it is a property of the
induction variable.

test/Transforms/LoopUnroll/nsw-tripcount.ll was added to solely test
functionality I'm reverting in this change, so I've deleted the test
fully.

llvm-svn: 273079
2016-06-18 04:38:31 +00:00
George Burgess IV 24eb0daf7c [CFLAA] Tag arguments as escaped instead of unknown.
This patch also includes some refactoring.

Prior to this patch, we tagged all CFLAA attributes as unknown. This is
suboptimal, since it meant that any Value used as an argument would be
considered to alias any other Value that existed.

Now that we have the machinery to tag sets below the set for an
arbitrary value with attributes, it's okay to be less conservative with
arguments. (Specifically, we still tag the set under an argument with
unknown).

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21262

llvm-svn: 272690
2016-06-14 18:12:28 +00:00
Simon Pilgrim 3fc09f7be6 [CostModel][X86][SSE] Updated costs for vector BITREVERSE ops on SSSE3+ targets
To account for the fast PSHUFB implementation now available

llvm-svn: 272484
2016-06-11 19:23:02 +00:00
Michael Kuperstein 9a0542a792 [X86] Add costs for SSE zext/sext to v4i64 to TTI
The costs are somewhat hand-wavy, but should be much closer to the truth
than what we get from BasicTTI.

Differential Revision: http://reviews.llvm.org/D21156

llvm-svn: 272406
2016-06-10 17:01:05 +00:00
George Burgess IV 652ec4f595 [CFLAA] Handle global/arg attrs more sanely.
Prior to this patch, we used argument/global stratified attributes in
order to note that a value could have come from either dereferencing a
global/arg, or from the assignment from a global/arg.

Now, AttrUnknown is placed on sets when we see a dereference, instead of
the global/arg attributes. This allows us to be more aggressive in the
future when we see global/arg attributes without AttrUnknown.

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21110

llvm-svn: 272335
2016-06-09 23:15:04 +00:00
Sanjoy Das c7f69b921f Be wary of abnormal exits from loop when exploiting UB
We can safely rely on a NoWrap add recurrence causing UB down the road
only if we know the loop does not have a exit expressed in a way that is
opaque to ScalarEvolution (e.g. by a function call that conditionally
calls exit(0)).

I believe with this change PR28012 is fixed.

Note: I had to change some llvm-lit tests in LoopReroll, since it looks
like they were depending on this incorrect behavior.

llvm-svn: 272237
2016-06-09 01:13:59 +00:00
Sanjoy Das 8598412e24 [SCEV] Track no-abnormal-exits instead of no-throw calls
Absence of may-unwind calls is not enough to guarantee that a
UB-generating use of an add-rec poison in the loop latch will actually
cause UB.  We also need to guard against calls that terminate the thread
or infinite loop themselves.

This partially addresses PR28012.

llvm-svn: 272181
2016-06-08 17:48:42 +00:00
Sanjoy Das 9a65cd214d Teach isGuarantdToTransferExecToSuccessor about debug info intrinsics
Calls to `@llvm.dbg.*` can be assumed to terminate.

llvm-svn: 272180
2016-06-08 17:48:36 +00:00
Sanjoy Das a19edc4d15 Fix a bug in SCEV's poison value propagation
The worklist algorithm introduced in rL271151 didn't check to see if the
direct users of the post-inc add recurrence propagates poison.  This
change fixes the problem and makes the code structure more obvious.

Note for release managers: correctness wise, this bug wasn't a
regression introduced by rL271151 -- the behavior of SCEV around
post-inc add recurrences was strictly improved (in terms of correctness)
in rL271151.

llvm-svn: 272179
2016-06-08 17:48:31 +00:00
George Burgess IV a1f9a2daeb [CFLAA] Add AttrEscaped, remove bit twiddling functions.
This patch does a few things:

- Unifies AttrAll and AttrUnknown (since they were used for more or less
  the same purpose anyway).

- Introduces AttrEscaped, an attribute that notes that a value escapes
  our analysis for a given set, but not that an unknown value flows into
  said set.

- Removes functions that take bit indices, since we also had functions
  that took bitsets, and the use of both (with similar names) was
  unclear and bug-prone.

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21000

llvm-svn: 272040
2016-06-07 18:35:37 +00:00
Andrey Turetskiy 9f02c58670 [LAA] Improve non-wrapping pointer detection by handling loop-invariant case.
This fixes PR26314. This patch adds new helper “isNoWrap” with detection of
loop-invariant pointer case.

Patch by Roman Shirokiy.

Ref: https://llvm.org/bugs/show_bug.cgi?id=26314

Differential Revision: http://reviews.llvm.org/D17268

llvm-svn: 272014
2016-06-07 14:55:27 +00:00
Easwaran Raman 019e0bf592 Reapply r271728 after adding move cobstructor for ProfileSummaryInfo
llvm-svn: 271745
2016-06-03 22:54:26 +00:00
Easwaran Raman 94edaaaefb Revert r271728 as it breaks Windows build
llvm-svn: 271738
2016-06-03 21:14:26 +00:00
Easwaran Raman d142050f3a Analysis pass to access profile summary info
Differential Revision: http://reviews.llvm.org/D20648

llvm-svn: 271728
2016-06-03 20:37:19 +00:00
Daniel Berlin 73694bb92b Revert "Claim NoAlias if two GEPs index different fields of the same struct"
This reverts commit 2d5d6493f43eb68493a3852b8c226ac9fafdc7eb.

llvm-svn: 271422
2016-06-01 18:55:32 +00:00