Commit Graph

139 Commits

Author SHA1 Message Date
Paul Redmond 2adb13c100 LoopVectorize: support vectorizing intrinsic calls
- added function to VectorTargetTransformInfo to query cost of intrinsics
- vectorize trivially vectorizable intrinsic calls such as sin, cos, log, etc.

Reviewed by: Nadav

llvm-svn: 169711
2012-12-09 20:42:17 +00:00
Paul Redmond f7cd6b391a test commit.
llvm-svn: 169709
2012-12-09 19:46:31 +00:00
Nadav Rotem a8f026e2d4 LoopVectorizer: Increase the number of pointers that can be tested at runtime. If we cant prove statically that the pointers are disjoint then we add the runtime check.
llvm-svn: 169334
2012-12-04 23:25:24 +00:00
Nadav Rotem 87fc988c5d Enable if-conversion during vectorization.
llvm-svn: 169331
2012-12-04 22:59:52 +00:00
Nadav Rotem 93fa5ef957 Fix a bug in vectorization of if-converted reduction variables. If the
reduction variable is not used outside the loop then we ran into an
endless loop. This change checks if we found the original PHI.

llvm-svn: 169324
2012-12-04 22:40:22 +00:00
Nadav Rotem a10b311aec Add support for reduction variables when IF-conversion is enabled.
llvm-svn: 169288
2012-12-04 18:17:33 +00:00
Nadav Rotem 07674cb566 Give scalar if-converted blocks half the score because they are not always executed due to CF.
llvm-svn: 169223
2012-12-04 07:11:52 +00:00
Nadav Rotem 628c2dba60 Add the last part that is needed for vectorization of if-converted code.
Added the code that actually performs the if-conversion during vectorization.

We can now vectorize this code:

for (int i=0; i<n; ++i) {
  unsigned k = 0;

  if (a[i] > b[i])   <------ IF inside the loop.
    k = k * 5 + 3;

  a[i] = k;          <---- K is a phi node that becomes vector-select.
}

llvm-svn: 169217
2012-12-04 06:15:11 +00:00
NAKAMURA Takumi f99b535fdb LoopVectorize.cpp: Suppress a warning. [-Wunused-variable]
llvm-svn: 169195
2012-12-04 00:49:34 +00:00
NAKAMURA Takumi 8b07bc579b Fix whitespace.
llvm-svn: 169194
2012-12-04 00:49:28 +00:00
Nadav Rotem d479a57f68 minor renaming, documentation and cleanups.
llvm-svn: 169175
2012-12-03 22:57:09 +00:00
Nadav Rotem fad16be973 IF-conversion: teach the cost-model how to grade if-converted loops.
llvm-svn: 169171
2012-12-03 22:46:31 +00:00
Nadav Rotem eee203d885 Now that we have a basic if-conversion infrastructure we can rename the
"single basic block loop vectorizer" to "innermost loop vectorizer".

llvm-svn: 169158
2012-12-03 21:33:08 +00:00
Nadav Rotem a30aba7a01 Add initial support for IF-conversion. This patch implements the first 1/3,
which is the legality of the if-conversion transformation. The next step is to
implement the cost-model for the if-converted code as well as the
vectorization itself.

llvm-svn: 169152
2012-12-03 21:06:35 +00:00
Chandler Carruth ed0881b2a6 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

llvm-svn: 169131
2012-12-03 16:50:05 +00:00
Nadav Rotem 3ae24ee08a minor cleanups
llvm-svn: 169048
2012-11-30 22:37:11 +00:00
Nadav Rotem 6b494be886 Remove the use of LPPassManager. We can remove LPM because we dont need to run any additional loop passes on the new vector loop.
llvm-svn: 169016
2012-11-30 17:27:53 +00:00
Nadav Rotem 8dd6ee8df5 When broadcasting invariant scalars into vectors, place the broadcast code in the preheader.
llvm-svn: 168927
2012-11-29 19:25:41 +00:00
Hal Finkel 88ee6b0082 BBVectorize: Correctly merge SubclassOptionalData
When two instructions are combined into a vector instruction,
the resulting instruction must have the most-conservative flags.

llvm-svn: 168765
2012-11-28 03:04:10 +00:00
Nadav Rotem caf5acfd14 Move the code that uses SCEVs prior to creating the new loops.
llvm-svn: 168601
2012-11-26 19:51:46 +00:00
Nadav Rotem ee7ede76f4 Move the max vector width to a constant parameter. No functionality change.
llvm-svn: 168570
2012-11-25 16:48:08 +00:00
Nadav Rotem ef33b5076c Fix the document style.
llvm-svn: 168569
2012-11-25 16:39:01 +00:00
Nadav Rotem 12192f19eb Refactor the ptr runtime check generation code. No functionality change.
llvm-svn: 168568
2012-11-25 16:27:16 +00:00
Nadav Rotem b15d9fe24d Rename method. No functionality change.
llvm-svn: 168560
2012-11-25 09:13:57 +00:00
Nadav Rotem bf5173460f The induction-pointer work is inspired by a research paper. This commit adds a reference.
llvm-svn: 168559
2012-11-25 09:09:26 +00:00
Nadav Rotem ea3824f160 Add support for pointer induction variables even when there is no integer induction variable.
llvm-svn: 168558
2012-11-25 08:41:35 +00:00
Nadav Rotem c3c07e62e8 LoopVectorizer: Add initial support for pointer induction variables (for example: *dst++ = *src++).
At the moment we still require to have an integer induction variable (for example: i++).

llvm-svn: 168231
2012-11-17 00:27:03 +00:00
Nadav Rotem 0565b5a279 LoopVectorize: Division reductions generate incorrect code. Remove the part of the code that deals with divs.
Thanks to Paul Redmond for catching this while reviewing the code.

llvm-svn: 168142
2012-11-16 06:51:17 +00:00
Hal Finkel e9740a4692 Replace std::vector -> SmallVector in BBVectorize
For now, this uses 8 on-stack elements. I'll need to do some profiling
to see if this is the best number.

Pointed out by Jakob in post-commit review.

llvm-svn: 167966
2012-11-14 19:53:27 +00:00
Hal Finkel 1b7f0aba48 Fix the largest offender of determinism in BBVectorize
Iterating over the children of each node in the potential vectorization
plan must happen in a deterministic order (because it affects which children
are erased when two children conflict). There was no need for this data
structure to be a map in the first place, so replacing it with a vector
is a small change.

I believe that this was the last remaining instance if iterating over the
elements of a Dense* container where the iteration order could matter.
There are some remaining iterations over std::*map containers where the order
might matter, but so long as the Value* for instructions in a block increase
with the order of the instructions in the block (or decrease) monotonically,
then this will appear to be deterministic.

llvm-svn: 167942
2012-11-14 18:38:11 +00:00
Nadav Rotem a43bcddc8d use the getSplat API. Patch by Paul Redmond.
llvm-svn: 167892
2012-11-14 00:02:13 +00:00
Hal Finkel b51bdd20d3 BBVectorize: Remove temporary assert used for debugging
llvm-svn: 167817
2012-11-13 05:54:54 +00:00
Hal Finkel 2a1df367d4 BBVectorize: Don't vectorize vector-manipulation chains
Don't choose a vectorization plan containing only shuffles and
vector inserts/extracts. Due to inperfections in the cost model,
these can lead to infinite recusion.

llvm-svn: 167811
2012-11-13 03:12:40 +00:00
Hal Finkel 3b79f55c5f BBVectorize: Only some insert element operand pairs are free.
This fixes another infinite recursion case when using target costs.
We can only replace insert element input chains that are pure (end
with inserting into an undef).

llvm-svn: 167784
2012-11-12 23:55:36 +00:00
Hal Finkel 9cf3372931 BBVectorize: Use a more sophisticated check for input cost
The old checking code, which assumed that input shuffles and insert-elements
could always be folded (and thus were free) is too simple.
This can only happen in special circumstances.
Using the simple check caused infinite recursion.

llvm-svn: 167750
2012-11-12 21:21:02 +00:00
Hal Finkel f8326b6052 BBVectorize: Check the types of compare instructions
The pass would previously assert when trying to compute the cost of
compare instructions with illegal vector types (like struct pointers).

llvm-svn: 167743
2012-11-12 19:41:38 +00:00
Hal Finkel ef53df0f9f BBVectorize: Check the input types of shuffles for legality
This fixes a bug where shuffles were being fused such that the
resulting input types were not legal on the target. This would
occur only when both inputs and dependencies were also foldable
operations (such as other shuffles) and there were other connected
pairs in the same block.

llvm-svn: 167731
2012-11-12 14:50:59 +00:00
Nadav Rotem 12930749ab Fix a comment typo and add comments.
llvm-svn: 167684
2012-11-11 05:15:00 +00:00
Nadav Rotem 1cfef3e9ee Add support for memory runtime check. When we can, we calculate array bounds.
If the arrays are found to be disjoint then we run the vectorized version of
the loop. If they are not, we run the scalar code.

llvm-svn: 167608
2012-11-09 07:09:44 +00:00
Chandler Carruth acc748b2b5 Fix sign compare warning. Patch by Mahesha HS.
llvm-svn: 167282
2012-11-02 05:24:00 +00:00
Hal Finkel 560545b85f BBVectorize: Use target costs for incoming and outgoing values instead of the depth heuristic.
When target cost information is available, compute explicit costs of inserting and
extracting values from vectors. At this point, all costs are estimated using the
target information, and the chain-depth heuristic is not needed. As a result, it is now, by
default, disabled when using target costs.

llvm-svn: 167256
2012-11-01 21:50:12 +00:00
Hal Finkel c89e75e93e BBVectorize: Account for internal shuffle costs
When target costs are available, use them to account for the costs of
shuffles on internal edges of the DAG of candidate pairs.

Because the shuffle costs here are currently for only the internal edges,
the current target cost model is trivial, and the chain depth requirement
is still in place, I don't yet have an easy test
case. Nevertheless, by looking at the debug output, it does seem to do the right
think to the effective "size" of each DAG of candidate pairs.

llvm-svn: 167217
2012-11-01 06:26:34 +00:00
Nadav Rotem 4cb8cdab5e LoopVectorize: Preserve NSW, NUW and IsExact flags.
llvm-svn: 167174
2012-10-31 21:40:39 +00:00
Nadav Rotem ec3ab49dda Put the threshold magic number in a variable.
llvm-svn: 167134
2012-10-31 16:22:16 +00:00
Nadav Rotem 1265ea8f8d Remove enum values since they are not used anymore.
llvm-svn: 167131
2012-10-31 16:14:06 +00:00
Hal Finkel 842ad0b621 BBVectorize: Choose pair ordering to minimize shuffles
BBVectorize would, except for loads and stores, always fuse instructions
so that the first instruction (in the current source order) would always
represent the low part of the input vectors and the second instruction
would always represent the high part. This lead to too many shuffles
being produced because sometimes the opposite order produces fewer of them.

With this change, BBVectorize tracks the kind of pair connections that form
the DAG of candidate pairs, and uses that information to reorder the pairs to
avoid excess shuffles. Using this information, a future commit will be able
to add VTTI-based shuffle costs to the pair selection procedure. Importantly,
the number of remaining shuffles can now be estimated during pair selection.

There are some trivial instruction reorderings in the test cases, and one
simple additional test where we certainly want to do a reordering to
avoid an unnecessary shuffle.

llvm-svn: 167122
2012-10-31 15:17:07 +00:00
Nadav Rotem ce77ab0c24 LoopVectorize: Do not vectorize loops with tiny constant trip counts.
llvm-svn: 167101
2012-10-31 03:31:07 +00:00
Nadav Rotem ff7889196b Add support for loops that don't start with Zero.
This is important for loops in the LAPACK test-suite.
These loops start at 1 because they are auto-converted from fortran.

llvm-svn: 167084
2012-10-31 00:45:26 +00:00
Nadav Rotem 47a299dcc9 Add documentation.
llvm-svn: 167055
2012-10-30 22:06:26 +00:00
Hal Finkel 08f34ac9dd BBVectorize: Cache fixed-order pairs instead of recomputing pointer info.
Instead of recomputing relative pointer information just prior to fusing,
cache this information (which also needs to be computed during the
candidate-pair selection process). This cuts down on the total number of
SE queries made, and also is a necessary intermediate step on the road toward
including shuffle costs in the pair selection procedure.

No functionality change is intended.

llvm-svn: 167049
2012-10-30 20:17:37 +00:00