Commit Graph

687 Commits

Author SHA1 Message Date
Erik Eckstein
04075c619b SLPVectorizer: limit the number of alias checks to reduce the runtime.
In case of blocks with many memory-accessing instructions, alias checking can take lot of time
(because calculating the memory dependencies has quadratic complexity).
I chose a limit which resulted in no changes when running the benchmarks.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226439 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 09:33:38 +00:00
Chandler Carruth
5a2d01e5b8 [PM] Now that LoopInfo isn't in the Pass type hierarchy, it is much
cleaner to derive from the generic base.

Thise removes a ton of boiler plate code and somewhat strange and
pointless indirections. It also remove a bunch of the previously needed
friend declarations. To fully remove these, I also lifted the verify
logic into the generic LoopInfoBase, which seems good anyways -- it is
generic and useful logic even for the machine side.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226385 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-18 01:25:51 +00:00
Chandler Carruth
de5df29556 [PM] Split the LoopInfo object apart from the legacy pass, creating
a LoopInfoWrapperPass to wire the object up to the legacy pass manager.

This switches all the clients of LoopInfo over and paves the way to port
LoopInfo to the new pass manager. No functionality change is intended
with this iteration.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226373 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-17 14:16:18 +00:00
Alexander Kornienko
b4c6267f7c Replace size method call of containers to empty method where appropriate
This patch was generated by a clang tidy checker that is being open sourced.
The documentation of that checker is the following:

/// The emptiness of a container should be checked using the empty method
/// instead of the size method. It is not guaranteed that size is a
/// constant-time function, and it is generally more efficient and also shows
/// clearer intent to use empty. Furthermore some containers may implement the
/// empty method but not implement the size method. Using empty whenever
/// possible makes it easier to switch to another container in the future.

Patch by Gábor Horváth!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226161 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-15 11:41:30 +00:00
Chandler Carruth
eeeec3ce0d [PM] Separate the TargetLibraryInfo object from the immutable pass.
The pass is really just a means of accessing a cached instance of the
TargetLibraryInfo object, and this way we can re-use that object for the
new pass manager as its result.

Lots of delta, but nothing interesting happening here. This is the
common pattern that is developing to allow analyses to live in both the
old and new pass manager -- a wrapper pass in the old pass manager
emulates the separation intrinsic to the new pass manager between the
result and pass for analyses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226157 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-15 10:41:28 +00:00
NAKAMURA Takumi
20b033eae5 Update libdeps since TLI was moved from Target to Analysis in r226078.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226126 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-15 05:21:00 +00:00
Erik Eckstein
d6238e7b7e reapply: SLPVectorizer: Cache results from memory alias checking.
This speeds up the dependency calculations for blocks with many load/store/call instructions.
Beside the improved runtime, there is no functional change.

Compared to the original commit, this re-applied commit contains a bug fix which ensures that there are
no incorrect collisions in the alias cache.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225977 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 11:24:47 +00:00
Hao Liu
e928b4046a Fix a wrong comment in LoopVectorize.
I.E. more than two -> exactly two
Fix a typo function name in LoopVectorize.
  I.E. collectStrideAcccess() -> collectStrideAccess()


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225935 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 03:02:16 +00:00
Julien Lerouge
88e1d95d4d Fix non-determinism issue in SLP
The issue was introduced in r214638:

+  for (auto &BSIter : BlocksSchedules) {
+    scheduleBlock(BSIter.second.get());
+  }

Because BlocksSchedules is a DenseMap with BasicBlock* keys, blocks are
scheduled in non-deterministic order, resulting in unpredictable IR.

Patch by Daniel Reynaud!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225821 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 19:45:52 +00:00
Erik Eckstein
046c3e807d Revert "SLPVectorizer: Cache results from memory alias checking."
The alias cache has a problem of incorrect collisions in case a new instruction is allocated at the same address as a previously deleted instruction.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225790 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 14:36:46 +00:00
Erik Eckstein
5b23df7cd8 SLPVectorizer: Cache results from memory alias checking.
This speeds up the dependency calculations for blocks with many load/store/call instructions.
Beside the improved runtime, there is no functional change.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225786 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 11:37:51 +00:00
Michael Zolotukhin
d23518097e Update comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225553 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-09 22:15:06 +00:00
Michael Zolotukhin
b2e5f58de0 Remove duplicating code. NFC.
The removed condition is checked in the previous loop.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225542 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-09 20:36:19 +00:00
Suyog Sarda
df970d6297 Assumption that "VectorizedValue" will always be an Instruction is not correct.
It can be a constant or a vector argument.

ex :

define i32 @hadd(<4 x i32> %a) #0 {
entry:
  %vecext = extractelement <4 x i32> %a, i32 0
  %vecext1 = extractelement <4 x i32> %a, i32 1
  %add = add i32 %vecext, %vecext1
  %vecext2 = extractelement <4 x i32> %a, i32 2
  %add3 = add i32 %add, %vecext2
  %vecext4 = extractelement <4 x i32> %a, i32 3
  %add5 = add i32 %add3, %vecext4
  ret i32 %add5
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225517 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-09 10:23:48 +00:00
Jiangning Liu
614fe873ce Fixed a bug in memory dependence checking module of loop vectorization. The following loop should not be vectorized with current algorithm.
{code}
// loop body
   ... = a[i]          (1)
    ... = a[i+1]       (2)
 .......
a[i+1] = ....          (3)
   a[i] = ...          (4)
{code}

The algorithm tries to collect memory access candidates from AliasSetTracker, and then check memory dependences one another. The memory accesses are unique in AliasSetTracker, and a single memory access in AliasSetTracker may map to multiple entries in AccessAnalysis, which could cover both 'read' and 'write'. Originally the algorithm only checked 'write' entry in Accesses if only 'write' exists. This is incorrect and the consequence is it ignored all read access, and finally some RAW and WAR dependence are missed.

For the case given above, if we ignore two reads, the dependence between (1) and (3) would not be able to be captured, and finally this loop will be incorrectly vectorized.

The fix simply inserts a new loop to find all entries in Accesses. Since it will skip most of all other memory accesses by checking the Value pointer at the very beginning of the loop, it should not increase compile-time visibly.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225159 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-05 10:08:58 +00:00
Chandler Carruth
5a9cd4d44e [PM] Split the AssumptionTracker immutable pass into two separate APIs:
a cache of assumptions for a single function, and an immutable pass that
manages those caches.

The motivation for this change is two fold. Immutable analyses are
really hacks around the current pass manager design and don't exist in
the new design. This is usually OK, but it requires that the core logic
of an immutable pass be reasonably partitioned off from the pass logic.
This change does precisely that. As a consequence it also paves the way
for the *many* utility functions that deal in the assumptions to live in
both pass manager worlds by creating an separate non-pass object with
its own independent API that they all rely on. Now, the only bits of the
system that deal with the actual pass mechanics are those that actually
need to deal with the pass mechanics.

Once this separation is made, several simplifications become pretty
obvious in the assumption cache itself. Rather than using a set and
callback value handles, it can just be a vector of weak value handles.
The callers can easily skip the handles that are null, and eventually we
can wrap all of this up behind a filter iterator.

For now, this adds boiler plate to the various passes, but this kind of
boiler plate will end up making it possible to port these passes to the
new pass manager, and so it will end up factored away pretty reasonably.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225131 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-04 12:03:27 +00:00
Elena Demikhovsky
cc794daa67 Some code improvements in Masked Load/Store.
No functional changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224986 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-30 14:28:14 +00:00
Elena Demikhovsky
b31322328a Masked Load/Store - Changed the order of parameters in intrinsics.
No functional changes.
The documentation is coming.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224829 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-25 07:49:20 +00:00
Tilmann Scheller
409585877a [BBVectorize] Remove two more redundant assignments.
Found by the Clang static analyzer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224590 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 17:21:38 +00:00
Tilmann Scheller
14ef1a43c2 [BBVectorize] Remove redundant assignment.
Found by the Clang static analyzer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224589 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 17:13:12 +00:00
Tilmann Scheller
b8b0b8f0a8 [LoopVectorize] Remove redundant assignment.
Found by the Clang static analyzer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224587 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 17:02:31 +00:00
Suyog Sarda
4bfc4f2e8c Revert 224119 "This patch recognizes (+ (+ v0, v1) (+ v2, v3)), reorders them for bundling into vector of loads,
and vectorizes it." 

This was re-ordering floating point data types resulting in mismatch in output.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224424 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-17 10:34:27 +00:00
Elena Demikhovsky
14fb445715 Masked Load and Store Intrinsics in loop vectorizer.
The loop vectorizer optimizes loops containing conditional memory
accesses by generating masked load and store intrinsics.
This decision is target dependent.

http://reviews.llvm.org/D6527



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224334 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-16 11:50:42 +00:00
Elena Demikhovsky
1c3a1516f8 Loop Vectorizer minor changes in the code -
some comments, function names, identation.

Reviewed here: http://reviews.llvm.org/D6527


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224218 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-14 09:43:50 +00:00
Suyog Sarda
1dea0dc279 This patch recognizes (+ (+ v0, v1) (+ v2, v3)), reorders them for bundling into vector of loads,
and vectorizes it. 
 
 Test case :
 
       float hadd(float* a) {
           return (a[0] + a[1]) + (a[2] + a[3]);
        }
 
 
 AArch64 assembly before patch :
 
        ldp	s0, s1, [x0]
 	ldp	s2, s3, [x0, #8]
 	fadd	s0, s0, s1
 	fadd	s1, s2, s3
 	fadd	s0, s0, s1
 	ret
 
 AArch64 assembly after patch :
 
        ldp	d0, d1, [x0]
 	fadd	v0.2s, v0.2s, v1.2s
 	faddp	s0, v0.2s
 	ret

Reviewed Link : http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20141208/248531.html



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224119 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-12 12:53:44 +00:00
Michael Zolotukhin
c9f47d8821 Remove redundant variable.
Tested by adding assert(LoopVectorPreHeader == VecPreheader) on LLVM
test suite and SPECs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223847 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-09 22:45:07 +00:00
Duncan P. N. Exon Smith
dad20b2ae2 IR: Split Metadata from Value
Split `Metadata` away from the `Value` class hierarchy, as part of
PR21532.  Assembly and bitcode changes are in the wings, but this is the
bulk of the change for the IR C++ API.

I have a follow-up patch prepared for `clang`.  If this breaks other
sub-projects, I apologize in advance :(.  Help me compile it on Darwin
I'll try to fix it.  FWIW, the errors should be easy to fix, so it may
be simpler to just fix it yourself.

This breaks the build for all metadata-related code that's out-of-tree.
Rest assured the transition is mechanical and the compiler should catch
almost all of the problems.

Here's a quick guide for updating your code:

  - `Metadata` is the root of a class hierarchy with three main classes:
    `MDNode`, `MDString`, and `ValueAsMetadata`.  It is distinct from
    the `Value` class hierarchy.  It is typeless -- i.e., instances do
    *not* have a `Type`.

  - `MDNode`'s operands are all `Metadata *` (instead of `Value *`).

  - `TrackingVH<MDNode>` and `WeakVH` referring to metadata can be
    replaced with `TrackingMDNodeRef` and `TrackingMDRef`, respectively.

    If you're referring solely to resolved `MDNode`s -- post graph
    construction -- just use `MDNode*`.

  - `MDNode` (and the rest of `Metadata`) have only limited support for
    `replaceAllUsesWith()`.

    As long as an `MDNode` is pointing at a forward declaration -- the
    result of `MDNode::getTemporary()` -- it maintains a side map of its
    uses and can RAUW itself.  Once the forward declarations are fully
    resolved RAUW support is dropped on the ground.  This means that
    uniquing collisions on changing operands cause nodes to become
    "distinct".  (This already happened fairly commonly, whenever an
    operand went to null.)

    If you're constructing complex (non self-reference) `MDNode` cycles,
    you need to call `MDNode::resolveCycles()` on each node (or on a
    top-level node that somehow references all of the nodes).  Also,
    don't do that.  Metadata cycles (and the RAUW machinery needed to
    construct them) are expensive.

  - An `MDNode` can only refer to a `Constant` through a bridge called
    `ConstantAsMetadata` (one of the subclasses of `ValueAsMetadata`).

    As a side effect, accessing an operand of an `MDNode` that is known
    to be, e.g., `ConstantInt`, takes three steps: first, cast from
    `Metadata` to `ConstantAsMetadata`; second, extract the `Constant`;
    third, cast down to `ConstantInt`.

    The eventual goal is to introduce `MDInt`/`MDFloat`/etc. and have
    metadata schema owners transition away from using `Constant`s when
    the type isn't important (and they don't care about referring to
    `GlobalValue`s).

    In the meantime, I've added transitional API to the `mdconst`
    namespace that matches semantics with the old code, in order to
    avoid adding the error-prone three-step equivalent to every call
    site.  If your old code was:

        MDNode *N = foo();
        bar(isa             <ConstantInt>(N->getOperand(0)));
        baz(cast            <ConstantInt>(N->getOperand(1)));
        bak(cast_or_null    <ConstantInt>(N->getOperand(2)));
        bat(dyn_cast        <ConstantInt>(N->getOperand(3)));
        bay(dyn_cast_or_null<ConstantInt>(N->getOperand(4)));

    you can trivially match its semantics with:

        MDNode *N = foo();
        bar(mdconst::hasa               <ConstantInt>(N->getOperand(0)));
        baz(mdconst::extract            <ConstantInt>(N->getOperand(1)));
        bak(mdconst::extract_or_null    <ConstantInt>(N->getOperand(2)));
        bat(mdconst::dyn_extract        <ConstantInt>(N->getOperand(3)));
        bay(mdconst::dyn_extract_or_null<ConstantInt>(N->getOperand(4)));

    and when you transition your metadata schema to `MDInt`:

        MDNode *N = foo();
        bar(isa             <MDInt>(N->getOperand(0)));
        baz(cast            <MDInt>(N->getOperand(1)));
        bak(cast_or_null    <MDInt>(N->getOperand(2)));
        bat(dyn_cast        <MDInt>(N->getOperand(3)));
        bay(dyn_cast_or_null<MDInt>(N->getOperand(4)));

  - A `CallInst` -- specifically, intrinsic instructions -- can refer to
    metadata through a bridge called `MetadataAsValue`.  This is a
    subclass of `Value` where `getType()->isMetadataTy()`.

    `MetadataAsValue` is the *only* class that can legally refer to a
    `LocalAsMetadata`, which is a bridged form of non-`Constant` values
    like `Argument` and `Instruction`.  It can also refer to any other
    `Metadata` subclass.

(I'll break all your testcases in a follow-up commit, when I propagate
this change to assembly.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223802 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-09 18:38:53 +00:00
Duncan P. N. Exon Smith
5ed8a767a0 LoopVectorize: Remove unnecessary RAUW
Remove an unnecessary `MDNode::replaceAllUsesWith()`.  In the preceding
line, `TheLoop->setLoopID()` visits all backedges and sets the new loop
ID.  This sufficiently updates the loop metadata.

Metadata RAUW is going away as part of PR21532.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223210 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-03 05:41:20 +00:00
Michael Zolotukhin
97be10d98f PR21302. Vectorize only bottom-tested loops.
rdar://problem/18886083

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223171 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-02 22:59:06 +00:00
Duncan P. N. Exon Smith
54786a0936 Revert "Masked Vector Load and Store Intrinsics."
This reverts commit r222632 (and follow-up r222636), which caused a host
of LNT failures on an internal bot.  I'll respond to the commit on the
list with a reproduction of one of the failures.

Conflicts:
	lib/Target/X86/X86TargetTransformInfo.cpp

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222936 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-28 21:29:14 +00:00
Elena Demikhovsky
ae1ae2c3a1 Masked Vector Load and Store Intrinsics.
Introduced new target-independent intrinsics in order to support masked vector loads and stores. The loop vectorizer optimizes loops containing conditional memory accesses by generating these intrinsics for existing targets AVX2 and AVX-512. The vectorizer asks the target about availability of masked vector loads and stores.
Added SDNodes for masked operations and lowering patterns for X86 code generator.
Examples:
<16 x i32> @llvm.masked.load.v16i32(i8* %addr, <16 x i32> %passthru, i32 4 /* align */, <16 x i1> %mask)
declare void @llvm.masked.store.v8f64(i8* %addr, <8 x double> %value, i32 4, <8 x i1> %mask)

Scalarizer for other targets (not AVX2/AVX-512) will be done in a separate patch.

http://reviews.llvm.org/D6191



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222632 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-23 08:07:43 +00:00
Suyog Sarda
ca72befdb5 Vectorize a reduction chain feeding into a 'return' statement.
e.x 
return (a[0]+b[0]) + (a[1]+b[1])

Differential Revision: http://reviews.llvm.org/D6227



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222364 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-19 16:07:38 +00:00
David Blaikie
5401ba7099 Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool>
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.

This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222334 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-19 07:49:26 +00:00
Duncan P. N. Exon Smith
f4742f4c84 IR: Make MDString::getName() private
Hide the fact that `MDString`'s string is stored in `Value::Name` --
that's going to change soon.  Update the only in-tree client that was
using it instead of `Value::getString()`.

Part of PR21532.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221951 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-13 23:59:16 +00:00
Duncan P. N. Exon Smith
5bf8ade9d0 Revert "IR: MDNode => Value"
Instead, we're going to separate metadata from the Value hierarchy.  See
PR21532.

This reverts commit r221375.
This reverts commit r221373.
This reverts commit r221359.
This reverts commit r221167.
This reverts commit r221027.
This reverts commit r221024.
This reverts commit r221023.
This reverts commit r220995.
This reverts commit r220994.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221711 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-11 21:30:22 +00:00
David Majnemer
bb642c4369 LoopVectorize: Don't assume pointees are sized
A pointer's pointee might not be sized: the pointee could be a function.

Report this as IK_NoInduction when calculating isInductionVariable.

This fixes PR21508.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221501 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-07 00:31:14 +00:00
Duncan P. N. Exon Smith
5e84760dde IR: MDNode => Value: Instruction::getAllMetadataOtherThanDebugLoc()
Change `Instruction::getAllMetadataOtherThanDebugLoc()` from a vector of
`MDNode` to one of `Value`.  Part of PR21433.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221167 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-03 18:13:57 +00:00
Duncan P. N. Exon Smith
3a84a6377c IR: MDNode => Value: Instruction::getMetadata()
Change `Instruction::getMetadata()` to return `Value` as part of
PR21433.

Update most callers to use `Instruction::getMDNode()`, which wraps the
result in a `cast_or_null<MDNode>`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221024 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-01 00:10:31 +00:00
Michael Zolotukhin
cf19403e39 Correctly update dom-tree after loop vectorizer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221009 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-31 22:28:03 +00:00
NAKAMURA Takumi
81ae170379 Reformat partially, where I touched for whitespace changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220773 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-28 11:54:52 +00:00
NAKAMURA Takumi
0f06462959 Untabify and whitespace cleanups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220771 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-28 11:53:30 +00:00
Benjamin Kramer
1afcd6b4ff LoopVectorize: Simplify code. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220405 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-22 19:13:54 +00:00
Matt Arsenault
252134602f Add minnum / maxnum intrinsics
These are named following the IEEE-754 names for these
functions, rather than the libm fmin / fmax to avoid
possible ambiguities. Some languages may implement something
resembling fmin / fmax which return NaN if either operand is
to propagate errors. These implement the IEEE-754 semantics
of returning the other operand if either is a NaN representing
missing data.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220341 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-21 23:00:20 +00:00
Hal Finkel
6c15862fd3 [SLPVectorize] Basic ephemeral-value awareness
The SLP vectorizer should not vectorize ephemeral values. These are used to
express information to the optimizer, and vectorizing them does not lead to
faster code (because the ephemeral values are dropped prior to code generation,
vectorized or not), and obscures the information the instructions are
attempting to communicate (the logic that interprets the arguments to
@llvm.assume generically does not understand vectorized conditions).

Also, uses by ephemeral values are free (because they, and the necessary
extractelement instructions, will be dropped prior to code generation).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219816 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-15 17:35:01 +00:00
Eric Christopher
2ff93bfec6 No need to cache this unused variable.
Patch by Ehsan Akhgari.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219749 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-14 23:58:51 +00:00
Hal Finkel
75277b9f70 [LoopVectorize] Ignore @llvm.assume for cost estimates and legality
A few minor changes to prevent @llvm.assume from interfering with loop
vectorization. First, treat @llvm.assume like the lifetime intrinsics, which
are scalarized (but don't otherwise interfere with the legality checking).
Second, ignore the cost of ephemeral instructions in the loop (these will go
away anyway during CodeGen).

Alignment assumptions and other uses of @llvm.assume can often end up inside of
loops that should be vectorized (this is not uncommon for assumptions generated
by __attribute__((align_value(n))), for example).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219741 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-14 22:59:49 +00:00
Chandler Carruth
0b0126955a [SCEV] Fix one more caller blindly passing the latch to SCEV's
getSmallConstantTripCount even when it isn't the exiting block.

I missed this in my first audit, very sorry. This was found in LNT and
elsewhere. I don't have a test case, but it was completely obvious from
inspection that this was the problem. I'll see if I can reduce a test
case, but I'm not really hopeful, and the value seems quite low.

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2014-10-11 05:28:30 +00:00
Chandler Carruth
c13c09106e [SCEV] Add some asserts to the recently improved trip count computation
routines and fix all of the bugs they expose.

I hit a test case that crashed even without these asserts due to passing
a non-exiting latch to the ExitingBlock parameter of the trip count
computation machinery. However, when I add the nice asserts, it turns
out we have plenty of coverage of these bugs, they just didn't manifest
in crashers.

The core problem seems to stem from an assumption that the latch *is*
the exiting block. While this is often true, and somewhat the "normal"
way to think about loops, it isn't necessarily true. The correct way to
call the trip count routines in a *generic* fashion (that is, without
a particular exit in mind) is to just use the loop's single exiting
block if it has one. The trip count can't be computed generically unless
it does. This works great for the loop vectorizer. The loop unroller
actually *wants* to select the latch when it has to chose between
multiple exits because for unrolling it is the latch trips that matter.
But if this is the desire, it needs to explicitly guard for non-exiting
latches and check for the generic trip count in that case.

I've added the asserts, and added convenience APIs for querying the trip
count generically that check for a single exit block. I've kept the APIs
consistent between computing trip count and trip multiples.

Thansk to Mark for the help debugging and tracking down the *right* fix
here!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219550 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-11 00:12:11 +00:00
Sanjay Patel
87c977a52b Rename getMaximumUnrollFactor -> getMaxInterleaveFactor; also rename option names controlling this variable.
"Unroll" is not the appropriate name for this variable. Clang already uses 
the term "interleave" in pragmas and metadata for this.

Differential Revision: http://reviews.llvm.org/D5066



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2014-09-10 17:58:16 +00:00
Sanjay Patel
b89304eb7c Preserve IR flags (nsw, nuw, exact, fast-math) in SLP vectorizer (PR20802).
The SLP vectorizer should propagate IR-level optimization hints/flags (nsw, nuw, exact, fast-math)
when converting scalar instructions into vectors. But this isn't a simple copy - we need to take
the intersection (the logical 'and') of the sets of flags on the scalars.

The solution is further complicated because we can have non-uniform (non-SIMD) vector ops after:
http://reviews.llvm.org/D4015
http://llvm.org/viewvc/llvm-project?view=revision&revision=211339

The vast majority of changed files are existing tests that were not propagating IR flags, but I've
also added a new test file for focused testing of IR flag possibilities.

Differential Revision: http://reviews.llvm.org/D5172



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217051 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-03 17:40:30 +00:00