3059 Commits

Author SHA1 Message Date
Arnold Schwaighofer
0caddfc731 LoopVectorize: External uses must use the last value in a reduction cycle
Otherwise, we don't perform operations that would have been performed on
the scalar version.

Fixes PR17498.

llvm-svn: 192133
2013-10-07 21:05:43 +00:00
Arnold Schwaighofer
698d4ac8a8 SLPVectorizer: Sort inputs to commutative binary operations
Sort the operands of the other entries in the current vectorization root
according to the first entry's operands opcodes.

%conv0 = uitofp ...
%load0 = load float ...

= fmul %conv0, %load0
= fmul %load0, %conv1
= fmul %load0, %conv2

Make sure that we recursively vectorize <%conv0, %conv1, %conv2> and <%load0,
%load0, %load0>.

This makes it more likely to obtain vectorizable trees. We have to be careful
when we sort that we don't destroy 'good' existing ordering implied by source
order.

radar://15080067

llvm-svn: 191977
2013-10-04 20:39:16 +00:00
Matt Arsenault
0be1cb1c7b Don't use runtime bounds check between address spaces.
Don't vectorize with a runtime check if it requires a
comparison between pointers with different address spaces.
The values can't be assumed to be directly comparable.
Previously it would create an illegal bitcast.

llvm-svn: 191862
2013-10-02 22:38:17 +00:00
Yi Jiang
8fd1a806d5 Apply slp vectorization on fully-vectorizable tree of height 2
llvm-svn: 191852
2013-10-02 20:20:39 +00:00
Matt Arsenault
39d592fe48 Fix debug printing spacing.
Fix missing newlines, missing and extra spaces in printed messages.

llvm-svn: 191851
2013-10-02 20:04:29 +00:00
Matt Arsenault
cccbe16785 Fix comment grammar and capitalization.
llvm-svn: 191850
2013-10-02 20:04:26 +00:00
Benjamin Kramer
b9add84ef6 SLPVectorizer: Make store chain finding more aggressive with GetUnderlyingObject.
This recursively strips all GEPs like the existing code. It also handles bitcasts and
other operations that do not change the pointer value.

llvm-svn: 191847
2013-10-02 19:06:06 +00:00
Rafael Espindola
44fee4e0eb Remove several unused variables.
Patch by Alp Toker.

llvm-svn: 191757
2013-10-01 13:32:03 +00:00
Matt Arsenault
5ea37f8d89 Fix code duplication
llvm-svn: 191716
2013-10-01 00:01:14 +00:00
Benjamin Kramer
6e931528fe Convert manual insert point restores to the new RAII object.
llvm-svn: 191675
2013-09-30 15:40:17 +00:00
Benjamin Kramer
d36f1abefd IRBuilder: Add RAII objects to reset insertion points or fast math flags.
Inspired by the object from the SLPVectorizer. This found a minor bug in the
debug loc restoration in the vectorizer where the location of a following
instruction was attached instead of the location from the original instruction.

llvm-svn: 191673
2013-09-30 15:39:48 +00:00
Robert Wilhelm
2788d3ec99 Even more spelling fixes for "instruction".
llvm-svn: 191611
2013-09-28 13:42:22 +00:00
Robert Wilhelm
f0cfb83bb4 Fix spelling intruction -> instruction.
llvm-svn: 191610
2013-09-28 11:46:15 +00:00
Matt Arsenault
29f31735a2 Fix SLPVectorizer using wrong address space for load/store
llvm-svn: 191564
2013-09-27 21:24:57 +00:00
Justin Bogner
ca9bd8fac1 Transforms: Use getFirstNonPHI to set the insertion point for PHIs
We were previously using getFirstInsertionPt to insert PHI
instructions when vectorizing, but getFirstInsertionPt also skips past
landingpads, causing this to generate invalid IR.

We can avoid this issue by using getFirstNonPHI instead.

llvm-svn: 191526
2013-09-27 15:30:25 +00:00
Arnold Schwaighofer
07520324f5 SLPVectorize: Put horizontal reductions feeding a store under separate flag
Put them under a separate flag for experimentation. They are more likely to
interfere with loop vectorization which happens later in the pass pipeline.

llvm-svn: 191371
2013-09-25 14:02:32 +00:00
Yi Jiang
edf2d9179e set the cost of tiny trees to INT_MAX in SLP vectorizer to disable vectorization on them
llvm-svn: 191314
2013-09-24 17:26:43 +00:00
Arnold Schwaighofer
22639407d7 Revert "LoopVectorizer: Only allow vectorization of intrinsics."
Revert 191122 - with extra checks we are allowed to vectorize math library
function calls.

Standard library indentifiers are reserved names so functions with external
linkage must not overrided them. However, functions with internal linkage can.

Therefore, we can vectorize calls to math library functions with a check for
external linkage and matching signature. This matches what we do during
SelectionDAG building.

llvm-svn: 191206
2013-09-23 14:54:39 +00:00
Arnold Schwaighofer
d743feef81 SLPVectorizer: Fix multiline comment warning
llvm-svn: 191135
2013-09-21 05:37:30 +00:00
Arnold Schwaighofer
500242d4fe Reapply "SLPVectorizer: Handle more horizontal reductions (disabled)""
Reapply r191108 with a fix for a memory corruption error I introduced.  Of
course, we can't reference the scalars that we replace by vectorizing and then
call their eraseFromParent method. I only 'needed' the scalars to get the
DebugLoc. Just store the DebugLoc before actually vectorizing instead. As a nice
side effect, this also simplifies the interface between BoUpSLP and the
HorizontalReduction class to returning a value pointer (the vectorized tree
root).

radar://14607682

llvm-svn: 191123
2013-09-21 01:06:00 +00:00
Nadav Rotem
3371172a67 LoopVectorizer: Only allow vectorization of intrinsics. We can't know for sure that the functions 'abs' or 'round' are the functions from libm.
rdar://15012650

llvm-svn: 191122
2013-09-21 00:27:05 +00:00
Arnold Schwaighofer
f1dfbfdde1 Revert "SLPVectorizer: Handle more horizontal reductions (disabled)"
This reverts commit r191108.

The horizontal.ll test case fails under libgmalloc. Thanks Shuxin for pointing
this out to me.

llvm-svn: 191121
2013-09-21 00:06:20 +00:00
Arnold Schwaighofer
4724963112 SLPVectorizer: Handle more horizontal reductions (disabled)
Match reductions starting at binary operation feeding into a phi. The code
handles trees like

 r += v1 + v2 + v3 ...

and

 r += v1
 r += v2
 ...

and

 r *= v1 + v2 + ...

We currently only handle associative operations (add, fadd fast).

The code can now also handle reductions feeding into stores.

 a[i] = v1 + v2 + v3 + ...

The code is currently disabled behind the flag "-slp-vectorize-hor".  The cost
model for most architectures is not there yet.

I found one opportunity of a horizontal reduction feeding a phi in TSVC
(LoopRerolling-flt) and there are several opportunities where reductions feed
into stores.

radar://14607682

llvm-svn: 191108
2013-09-20 21:18:20 +00:00
Robert Lytton
f637e2cb23 Prevent LoopVectorizer and SLPVectorizer running if the target has no vector registers.
XCore target: Add XCoreTargetTransformInfo
This is where getNumberOfRegisters() resides, which in turn returns the
number of vector registers (=0).

llvm-svn: 190936
2013-09-18 12:43:35 +00:00
Craig Topper
be3e01e61f Revert accidental commit I had to make to get the test case in PR17268 to still work correctly.
llvm-svn: 190917
2013-09-18 04:10:17 +00:00
Craig Topper
98064b9f4d Lift alignment restrictions for load/store folding on VINSERTF128/VEXTRACTF128. Fixes PR17268.
llvm-svn: 190916
2013-09-18 03:55:53 +00:00
Arnold Schwaighofer
4a3dcaa193 SLPVectorizer: Don't vectorize phi nodes that use invoke values
We can't insert an insertelement after an invoke. We would have to split a
critical edge. So when we see a phi node that uses an invoke we just give up.

radar://14990770

llvm-svn: 190871
2013-09-17 17:03:29 +00:00
Arnold Schwaighofer
53e622cef4 Don't vectorize if there are outside loop users of the induction variable.
We would have to compute the pre increment value, either by computing it on
every loop iteration or by splitting the edge out of the loop and inserting a
computation for it there.

For now, just give up vectorizing such loops.

Fixes PR17179.

llvm-svn: 190790
2013-09-16 16:17:24 +00:00
Eli Friedman
05906faa4d Don't assert on invalid loop vectorization hint.
llvm-svn: 190450
2013-09-10 23:45:25 +00:00
Benjamin Kramer
934f6f39f4 LoopVectorize: PHI nodes are always at the beginning of a block, no need to scan the whole block.
llvm-svn: 190422
2013-09-10 18:46:15 +00:00
Yi Jiang
aeb5b46a85 In this patch we are trying to do two things:
1) If the width of vectorization list candidate is bigger than vector reg width, we will break it down to fit the vector reg.
2) We do not vectorize the width which is not power of two.

The performance result shows it will help some spec benchmarks. mesa improved 6.97% and ammp improved 1.54%. 

llvm-svn: 189830
2013-09-03 17:26:04 +00:00
Hal Finkel
6d09904cc9 Disable unrolling in the loop vectorizer when disabled in the pass manager
When unrolling is disabled in the pass manager, the loop vectorizer should also
not unroll loops. This will allow the -fno-unroll-loops option in Clang to
behave as expected (even for vectorizable loops). The loop vectorizer's
-force-vector-unroll option will (continue to) override the pass-manager
setting (including -force-vector-unroll=0 to force use of the internal
auto-selection logic).

In order to test this, I added a flag to opt (-disable-loop-unrolling) to force
disable unrolling through opt (the analog of -fno-unroll-loops in Clang). Also,
this fixes a small bug in opt where the loop vectorizer was enabled only after
the pass manager populated the queue of passes (the global_alias.ll test needed
a slight update to the RUN line as a result of this fix).

llvm-svn: 189499
2013-08-28 18:33:10 +00:00
Nadav Rotem
6b41f7cc4c Refactor 'vectorizeLoop' no functionality change.
This patch merges LoopVectorize of InnerLoopVectorizer and InnerLoopUnroller by adding checks for VF=1. This helps in erasing the Unroller code that is almost identical to the InnerLoopVectorizer code.

llvm-svn: 189391
2013-08-27 18:52:47 +00:00
Matt Arsenault
ed9f76d37b Fix inserting instructions before last in bundle.
The builder inserts from before the insert point,
not after, so this would insert before the last
instruction in the bundle instead of after it.

I'm not sure if this can actually be a problem
with any of the current insertions.

llvm-svn: 189285
2013-08-26 23:08:37 +00:00
Nadav Rotem
bdc9ff4498 LoopVectorize: Implement partial loop unrolling when vectorization is not profitable.
This patch enables unrolling of loops when vectorization is legal but not profitable.
We add a new class InnerLoopUnroller, that extends InnerLoopVectorizer and replaces some of the vector-specific logic with scalars.

This patch does not introduce any runtime regressions and improves the following workloads:

SingleSource/Benchmarks/Shootout/matrix -22.64%
SingleSource/Benchmarks/Shootout-C++/matrix -13.06%
External/SPEC/CINT2006/464_h264ref/464_h264ref  -3.99%
SingleSource/Benchmarks/Adobe-C++/simple_types_constant_folding -1.95%

llvm-svn: 189281
2013-08-26 22:33:26 +00:00
Yi Jiang
7107d41574 test commit. Remove blank line
llvm-svn: 189265
2013-08-26 18:57:55 +00:00
Matt Arsenault
bcd8c577d7 Fix unused variable in release build
llvm-svn: 189264
2013-08-26 18:38:29 +00:00
Matt Arsenault
8f21c838c0 Constify functions
llvm-svn: 189234
2013-08-26 17:56:38 +00:00
Matt Arsenault
39274be65f Vectorize starting from insertelements building a vector
llvm-svn: 189233
2013-08-26 17:56:35 +00:00
Matt Arsenault
8405888af1 Check if in set on insertion instead of separately
llvm-svn: 189179
2013-08-24 19:55:38 +00:00
Chandler Carruth
1c34afcb61 Teach the SLP vectorizer the correct way to check for consecutive access
using GEPs. Previously, it used a number of different heuristics for
analyzing the GEPs. Several of these were conservatively correct, but
failed to fall back to SCEV even when SCEV might have given a reasonable
answer. One was simply incorrect in how it was formulated.

There was good code already to recursively evaluate the constant offsets
in GEPs, look through pointer casts, etc. I gathered this into a form
code like the SLP code can use in a previous commit, which allows all of
this code to become quite simple.

There is some performance (compile time) concern here at first glance as
we're directly attempting to walk both pointers constant GEP chains.
However, a couple of thoughts:

1) The very common cases where there is a dynamic pointer, and a second
   pointer at a constant offset (usually a stride) from it, this code
   will actually not do any unnecessary work.

2) InstCombine and other passes work very hard to collapse constant
   GEPs, so it will be rare that we iterate here for a long time.

That said, if there remain performance problems here, there are some
obvious things that can improve the situation immensely. Doing
a vectorizer-pass-wide memoizer for each individual layer of pointer
values, their base values, and the constant offset is likely to be able
to completely remove redundant work and strictly limit the scaling of
the work to scrape these GEPs. Since this optimization was not done on
the prior version (which would still benefit from it), I've not done it
here. But if folks have benchmarks that slow down it should be straight
forward for them to add.

I've added a test case, but I'm not really confident of the amount of
testing done for different access patterns, strides, and pointer
manipulation.

llvm-svn: 189007
2013-08-22 12:45:17 +00:00
Matt Arsenault
f599d97449 Teach LoopVectorize about address space sizes
llvm-svn: 188980
2013-08-22 02:42:55 +00:00
Matt Arsenault
745832dcc9 Use attribute helper function
llvm-svn: 188916
2013-08-21 18:54:50 +00:00
Matt Arsenault
3c71dabd88 Fix typo
llvm-svn: 188915
2013-08-21 18:54:47 +00:00
Arnold Schwaighofer
e1f3ab69d1 SLPVectorizer: Fix invalid iterator errors
Update iterator when the SLP vectorizer changes the instructions in the basic
block by restarting the traversal of the basic block.

Patch by Yi Jiang!

Fixes PR 16899.

llvm-svn: 188832
2013-08-20 21:21:45 +00:00
Hal Finkel
0c5c01aa4a Add a llvm.copysign intrinsic
This adds a llvm.copysign intrinsic; We already have Libfunc recognition for
copysign (which is turned into the FCOPYSIGN SDAG node). In order to
autovectorize calls to copysign in the loop vectorizer, we need a corresponding
intrinsic as well.

In addition to the expected changes to the language reference, the loop
vectorizer, BasicTTI, and the SDAG builder (the intrinsic is transformed into
an FCOPYSIGN node, just like the function call), this also adds FCOPYSIGN to a
few lists in LegalizeVector{Ops,Types} so that vector copysigns can be
expanded.

In TargetLoweringBase::initActions, I've made the default action for FCOPYSIGN
be Expand for vector types. This seems correct for all in-tree targets, and I
think is the right thing to do because, previously, there was no way to generate
vector-values FCOPYSIGN nodes (and most targets don't specify an action for
vector-typed FCOPYSIGN).

llvm-svn: 188728
2013-08-19 23:35:46 +00:00
Joerg Sonnenberger
8e3050db51 PR 16899: Do not modify the basic block using the iterator, but keep the
next value. This avoids crashes due to invalidation.

Patch by Joey Gouly.

llvm-svn: 188605
2013-08-17 11:04:47 +00:00
Matt Arsenault
5cae894a13 Fix spelling
llvm-svn: 188506
2013-08-15 23:11:03 +00:00
Hal Finkel
1a61f621da BBVectorize: Add initial stores to the write set when tracking uses
When computing the use set of a store, we need to add the store to the write
set prior to iterating over later instructions. Otherwise, if there is a later
aliasing load of that store, that load will not be tagged as a use, and bad
things will happen.

trackUsesOfI still adds later dependent stores of an instruction to that
instruction's write set, but it never sees the original instruction, and so
when tracking uses of a store, the store must be added to the write set by the
caller.

Fixes PR16834.

llvm-svn: 188329
2013-08-13 23:34:32 +00:00
Nadav Rotem
e23147bbd4 Fix PR16797 - Support PHINodes with multiple inputs from the same basic block.
Do not generate new vector values for the same entries because we know that the incoming values
from the same block must be identical.

llvm-svn: 188185
2013-08-12 17:46:44 +00:00