Commit Graph

14 Commits

Author SHA1 Message Date
Hideki Saito
ea7f3035a0 [VPlan] Implement initial vector code generation support for simple outer loops.
Summary:
[VPlan] Implement vector code generation support for simple outer loops.

Context: Patch Series #1 for outer loop vectorization support in LV  using VPlan. (RFC: http://lists.llvm.org/pipermail/llvm-dev/2017-December/119523.html).
                                                          
This patch introduces vector code generation support for simple outer loops that are currently supported in the VPlanNativePath. Changes here essentially do the following:

  - force vector code generation using explicit vectorize_width

  - add conservative early returns in cost model and other places for VPlanNativePath

  - add code for setting up outer loop inductions 

  - support for widening non-induction PHIs that can result from inner loops and uniform conditional branches

  - support for generating uniform inner branches

We plan to add a handful C outer loop executable tests once the initial code generation support is committed. This patch is expected to be NFC for the inner loop vectorizer path. Since we are moving in the direction of supporting outer loop vectorization in LV, it may also be time to rename classes such as InnerLoopVectorizer. 

Reviewers: fhahn, rengolin, hsaito, dcaballe, mkuper, hfinkel, Ayal

Reviewed By: fhahn, hsaito

Subscribers: dmgreen, bollu, tschuett, rkruppe, rogfer01, llvm-commits

Differential Revision: https://reviews.llvm.org/D50820

llvm-svn: 342197
2018-09-14 00:36:00 +00:00
Diego Caballero
2a34ac86d3 [VPlan] Introduce VPlan-based dominator analysis.
The patch introduces dominator analysis for VPBlockBases and extend
VPlan's GraphTraits specialization with the required interfaces. Dominator
analysis will be necessary to perform some H-CFG transformations and
to introduce VPLoopInfo (LoopInfo analysis on top of the VPlan representation).

Reviewers: fhahn, rengolin, mkuper, hfinkel, mssimpso

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D48815

llvm-svn: 338310
2018-07-30 21:33:31 +00:00
Diego Caballero
d09530144a [VPlan][LV] Introduce condition bit in VPBlockBase
This patch introduces a VPValue in VPBlockBase to represent the condition
bit that is used as successor selector when a block has multiple successors.
This information wasn't necessary until now, when we are about to introduce
outer loop vectorization support in VPlan code gen.

Reviewers: fhahn, rengolin, mkuper, hfinkel, mssimpso

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D48814

llvm-svn: 336554
2018-07-09 15:57:09 +00:00
Florian Hahn
63cbcf98a5 [VPlanRecipeBase] Add eraseFromParent().
Reviewers: dcaballe, hsaito, mkuper, hfinkel

Reviewed By: dcaballe

Differential Revision: https://reviews.llvm.org/D48081

llvm-svn: 334951
2018-06-18 15:18:48 +00:00
Florian Hahn
3bcff3662c [VPlan] Fix sanitizer problem with insertBefore.
llvm-svn: 334943
2018-06-18 13:51:28 +00:00
Florian Hahn
7591e4e94a [VPlanRecipeBase] Add insertBefore helper.
Reviewers: dcaballe, mkuper, hfinkel, hsaito, mssimpso

Reviewed By: dcaballe

Differential Revision: https://reviews.llvm.org/D48080

llvm-svn: 334933
2018-06-18 11:34:17 +00:00
Nicola Zaghen
d34e60ca85 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
Vedant Kumar
e0b5f86b30 [STLExtras] Add distance() for ranges, pred_size(), and succ_size()
This commit adds a wrapper for std::distance() which works with ranges.
As it would be a common case to write `distance(predecessors(BB))`, this
also introduces `pred_size()` and `succ_size()` helpers to make that
easier to write.

Differential Revision: https://reviews.llvm.org/D46668

llvm-svn: 332057
2018-05-10 23:01:54 +00:00
Hal Finkel
7333aa9f16 [LV] NFC patch for moving VP*Recipe class definitions from LoopVectorize.cpp to VPlan.h
This is a small step forward to move VPlan stuff to where it should belong (i.e., VPlan.*):

  1. VP*Recipe classes in LoopVectorize.cpp are moved to VPlan.h.
  2. Many of VP*Recipe::print() and execute() definitions are still left in
     LoopVectorize.cpp since they refer to things declared in LoopVectorize.cpp. To
     be moved to VPlan.cpp at a later time.
  3. InterleaveGroup class is moved from anonymous namespace to llvm namespace.
     Referencing it in anonymous namespace from VPlan.h ended up in warning.

Patch by Hideki Saito, thanks!

Differential Revision: https://reviews.llvm.org/D41045

llvm-svn: 320900
2017-12-16 01:12:50 +00:00
Gil Rapaport
8b9d1f3c5b [LV] Model masking in VPlan, introducing VPInstructions
This patch adds a new abstraction layer to VPlan and leverages it to model the planned
instructions that manipulate masks (AND, OR, NOT), introduced during predication.

The new VPValue and VPUser classes model how data flows into, through and out
of a VPlan, forming the vertices of a planned Def-Use graph. The new
VPInstruction class is a generic single-instruction Recipe that models a
planned instruction along with its opcode, operands and users. See
VectorizationPlan.rst for more details.

Differential Revision: https://reviews.llvm.org/D38676

llvm-svn: 318645
2017-11-20 12:01:47 +00:00
Eugene Zelenko
6cadde7f40 [Transforms] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 316034
2017-10-17 21:27:42 +00:00
Ayal Zaks
1f58dda4e4 [LV] Fix PR34248 - recommit D32871 after revert r311304
Original commit r311077 of D32871 was reverted in r311304 due to failures
reported in PR34248.

This recommit fixes PR34248 by restricting the packing of predicated scalars
into vectors only when vectorizing, avoiding doing so when unrolling w/o
vectorizing. Added a test derived from the reproducer of PR34248.

llvm-svn: 311849
2017-08-27 12:55:46 +00:00
Chandler Carruth
bd6dc14230 Revert r311077: [LV] Using VPlan ...
This causes LLVM to assert fail on PPC64 and crash / infloop in other
cases. Filed http://llvm.org/PR34248 with reproducer attached.

llvm-svn: 311304
2017-08-20 23:17:11 +00:00
Ayal Zaks
6627883369 [LV] Using VPlan to model the vectorized code and drive its transformation
VPlan is an ongoing effort to refactor and extend the Loop Vectorizer. This
patch introduces the VPlan model into LV and uses it to represent the vectorized
code and drive the generation of vectorized IR.

In this patch VPlan models the vectorized loop body: the vectorized control-flow
is represented using VPlan's Hierarchical CFG, with predication refactored from
being a post-vectorization-step into a vectorization planning step modeling
if-then VPRegionBlocks, and generating code inline with non-predicated code. The
vectorized code within each VPBasicBlock is represented as a sequence of
Recipes, each responsible for modelling and generating a sequence of IR
instructions. To keep the size of this commit manageable the Recipes in this
patch are coarse-grained and capture large chunks of LV's code-generation logic.
The constructed VPlans are dumped in dot format under -debug.

This commit retains current vectorizer output, except for minor instruction
reorderings; see associated modifications to lit tests.

For further details on the VPlan model see docs/Proposals/VectorizationPlan.rst
and its references.

Authors: Gil Rapaport and Ayal Zaks

Differential Revision: https://reviews.llvm.org/D32871

llvm-svn: 311077
2017-08-17 09:29:59 +00:00