Commit Graph

23 Commits

Author SHA1 Message Date
Simon Pilgrim 03afbe783d [X86][AVX] Ensure broadcast loads respect dependencies
To allow broadcast loads of a non-zero'th vector element, lowerVectorShuffleAsBroadcast can replace a load with a new load with an adjusted address, but unfortunately we weren't ensuring that the new load respected the same dependencies.

This patch adds a TokenFactor and updates all dependencies of the old load to reference the new load instead.

Bug found during internal testing.

Differential Revision: https://reviews.llvm.org/D25039

llvm-svn: 283070
2016-10-02 15:59:15 +00:00
Simon Pilgrim fea5c7a051 [X86][AVX] Add test showing that VBROADCAST loads don't correctly respect dependencies
llvm-svn: 282613
2016-09-28 17:59:30 +00:00
Simon Pilgrim 5f71c909f0 [X86][AVX] Peek through bitcasts to find the source of broadcasts (reapplied)
AVX1 can only broadcast vectors as floats/doubles, so for 256-bit vectors we insert bitcasts if we are shuffling v8i32/v4i64 types. Unfortunately the presence of these bitcasts prevents the current broadcast lowering code from peeking through cases where we have concatenated / extracted vectors to create the 256-bit vectors.

This patch allows us to peek through bitcasts as long as the number of elements doesn't change (i.e. element bitwidth is the same) so the broadcast index is not affected.

Note this bitcast peek is different from the stage later on which doesn't care about the type and is just trying to find a load node.

As we're being more aggressive with bitcasts, we also need to ensure that the broadcast type is correctly bitcasted

Differential Revision: http://reviews.llvm.org/D21660

llvm-svn: 274013
2016-06-28 13:24:05 +00:00
Simon Pilgrim c15d217831 [X86][SSE] Added support for combining target shuffles to (V)PSHUFD/VPERMILPD/VPERMILPS immediate permutes
This patch allows target shuffles to be combined to single input immediate permute instructions - (V)PSHUFD/VPERMILPD/VPERMILPS - allowing more general pattern matching than what we current do and improves the likelihood of memory folding compared to existing patterns which tend to reuse the input in multiple arguments.

Further permute instructions (V)PSHUFLW/(V)PSHUFHW/(V)PERMQ/(V)PERMPD may be added in the future but its proven tricky to create tests cases for them so far. (V)PSHUFLW/(V)PSHUFHW is already handled quite well in combineTargetShuffle so it may be that removing some of that code may allow us to perform more of the combining in one place without duplication.

Differential Revision: http://reviews.llvm.org/D21148

llvm-svn: 273999
2016-06-28 08:08:15 +00:00
Nico Weber 1e058160dd Revert 273848, it caused PR28329
llvm-svn: 273879
2016-06-27 14:36:46 +00:00
Simon Pilgrim a45da385f8 [X86][AVX] Peek through bitcasts to find the source of broadcasts
AVX1 can only broadcast vectors as floats/doubles, so for 256-bit vectors we insert bitcasts if we are shuffling v8i32/v4i64 types. Unfortunately the presence of these bitcasts prevents the current broadcast lowering code from peeking through cases where we have concatenated / extracted vectors to create the 256-bit vectors.

This patch allows us to peek through bitcasts as long as the number of elements doesn't change (i.e. element bitwidth is the same) so the broadcast index is not affected.

Note this bitcast peek is different from the stage later on which doesn't care about the type and is just trying to find a load node.

Differential Revision: http://reviews.llvm.org/D21660

llvm-svn: 273848
2016-06-27 07:44:32 +00:00
Simon Pilgrim c02b72627a [X86][SSE] Lower 128-bit MOVDDUP with existing VBROADCAST mechanisms
We have a number of useful lowering strategies for VBROADCAST instructions (both from memory and register element 0) which the 128-bit form of the MOVDDUP instruction can make use of.

This patch tweaks lowerVectorShuffleAsBroadcast to enable it to broadcast 2f64 args using MOVDDUP as well.

It does require a slight tweak to the lowerVectorShuffleAsBroadcast mechanism as the existing MOVDDUP lowering uses isShuffleEquivalent which can match binary shuffles that can lower to (unary) broadcasts.

Differential Revision: http://reviews.llvm.org/D17680

llvm-svn: 262478
2016-03-02 11:43:05 +00:00
Simon Pilgrim c7bebcbfd8 [X86][AVX] Match broadcast loads through a bitcast
AVX1 v8i32/v4i64 shuffles are bitcasted to v8f32/v4f64, this patch peeks through any bitcast to check for a load node to allow broadcasts to occur.

This is a re-commit of r257055 after r257264 fixed 32-bit broadcast loads of i64 scalars.

llvm-svn: 257266
2016-01-09 20:59:39 +00:00
Simon Pilgrim 2e7a1849c9 [X86][AVX] Add support for i64 broadcast loads on 32-bit targets
Added 32-bit AVX1/AVX2 broadcast tests.

llvm-svn: 257264
2016-01-09 19:59:27 +00:00
Nico Weber 4324b9b236 Revert r257055, it caused PR26064.
llvm-svn: 257066
2016-01-07 15:01:46 +00:00
Simon Pilgrim bcc11a059e [X86][AVX] Match broadcast loads through a bitcast
AVX1 v8i32/v4i64 shuffles are bitcasted to v8f32/v4f64, this patch peeks through bitcasts to check for a load node to allow broadcasts to occur.

Follow up to D15310

llvm-svn: 257055
2016-01-07 11:34:27 +00:00
Simon Pilgrim 323e00d9c7 [X86][AVX] Fold loads + splats into broadcast instructions
On AVX and AVX2, BROADCAST instructions can load a scalar into all elements of a target vector.

This patch improves the lowering of 'splat' shuffles of a loaded vector into a broadcast - currently the lowering only works for cases where we are splatting the zero'th element, which is now generalised to any element.

Fix for PR23022

Differential Revision: http://reviews.llvm.org/D15310

llvm-svn: 255061
2015-12-08 22:17:11 +00:00
Simon Pilgrim 12301b0814 [X86][AVX] Added tests to load+broadcast non-zero'th vector elements
Baseline for an upcoming patch for PR23022

llvm-svn: 254898
2015-12-07 09:09:54 +00:00
Simon Pilgrim 38e93ea1cc [X86][AVX] Tidied up BROADCASTPD/BROADCASTPS tests
Regenerate tests using update_llc_test_checks.py

llvm-svn: 254886
2015-12-06 20:12:19 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +00:00
Robert Lougher 7d9084ffa1 Teach the DAGCombiner how to fold concat_vector nodes when the input is two
BUILD_VECTOR nodes, e.g.:

(concat_vectors (BUILD_VECTOR a1, a2, a3, a4), (BUILD_VECTOR b1, b2, b3, b4))
->
(BUILD_VECTOR a1, a2, a3, a4, b1, b2, b3, b4)

This fixes an issue with AVX, where a sequence was not recognized as a 256-bit
vbroadcast due to the concat_vectors.

llvm-svn: 201158
2014-02-11 15:42:46 +00:00
Nadav Rotem 15946e50c1 AVX2: Add an additional broadcast idiom.
llvm-svn: 156540
2012-05-10 12:39:13 +00:00
Nadav Rotem b86a3fb8d0 Generate AVX/AVX2 shuffles even when there is a memory op somewhere else in the program.
Starting r155461 we are able to select patterns for vbroadcast even when the load op is used by other users.

Fix PR11900.

llvm-svn: 156539
2012-05-10 12:22:05 +00:00
Nadav Rotem 82609df647 AVX2: Build splat vectors by broadcasting a scalar from the constant pool.
Previously we used three instructions to broadcast an immediate value into a
vector register.
On Sandybridge we continue to load the broadcasted value from the constant pool.

llvm-svn: 154284
2012-04-08 12:54:54 +00:00
Craig Topper 430f3f1bd6 Fix a crash in AVX2 when trying to broadcast a double into a 128-bit vector. There is no vbroadcastsd xmm, but we do need to support 64-bit integers broadcasted into xmm. Also factor the AVX check into the isVectorBroadcast function. This makes more sense since the AVX2 check was already inside.
llvm-svn: 147844
2012-01-10 08:23:59 +00:00
Nadav Rotem 37010002f2 AVX: Add support for vbroadcast from BUILD_VECTOR and refactor some of the vbroadcast code.
llvm-svn: 144720
2011-11-15 22:50:37 +00:00
Bruno Cardoso Lopes f61d1c072e Fix vbroadcast matching logic to early unmatch if the node doesn't have
only one use. Fix PR10825.

llvm-svn: 138951
2011-09-01 18:15:06 +00:00
Bruno Cardoso Lopes be5e987379 Introduce matching patterns for vbroadcast AVX instruction. The idea is to
match splats in the form (splat (scalar_to_vector (load ...))) whenever
the load can be folded. All the logic and instruction emission is
working but because of PR8156, there are no ways to match loads, cause
they can never be folded for splats. Thus, the tests are XFAILed, but
I've tested and exercised all the logic using a relaxed version for
checking the foldable loads, as if the bug was already fixed. This
should work out of the box once PR8156 gets fixed since MayFoldLoad will
work as expected.

llvm-svn: 137810
2011-08-17 02:29:19 +00:00