Commit Graph

66 Commits

Author SHA1 Message Date
Simon Pilgrim 71bb6850cf [X86][AVX] Only combine loads to broadcasts for legal types
Thanks to @echristo for spotting this.

llvm-svn: 354961
2019-02-27 11:17:25 +00:00
Simon Pilgrim 952abcefe4 [X86][AVX] EltsFromConsecutiveLoads - Add BROADCAST lowering support
This patch adds scalar/subvector BROADCAST handling to EltsFromConsecutiveLoads.

It mainly shows codegen changes to 32-bit code which failed to handle i64 loads, although 64-bit code is also using this new path to more efficiently combine to a broadcast load.

Differential Revision: https://reviews.llvm.org/D58053

llvm-svn: 354340
2019-02-19 15:57:09 +00:00
Simon Pilgrim e95550f508 [X86][AVX] Add VMOVDDUP-VPBROADCASTQ execution domain mapping
Noticed in D57514.

Differential Revision: https://reviews.llvm.org/D57519

llvm-svn: 352922
2019-02-01 21:41:30 +00:00
Simon Pilgrim 63f3383ece [X86][AVX] Fold broadcast(bitcast(src)) -> bitcast(broadcast(src))
llvm-svn: 352751
2019-01-31 14:04:07 +00:00
Craig Topper aa5eb2fbaa [X86] Force floating point values in constant pool decoding to print in scientific notation so they can't be confused with integers.
When the floating point constants are whole numbers they have no decimal point so look like integers, but mean something very different in something like an 'and' instruction.

Ideally we would just print a decimal point and a 0, but I couldn't see how to make APFloat::toString do that.

llvm-svn: 345488
2018-10-29 04:52:04 +00:00
Alina Sbirlea dfd14adeb0 Generalize MergeBlockIntoPredecessor. Replace uses of MergeBasicBlockIntoOnlyPred.
Summary:
Two utils methods have essentially the same functionality. This is an attempt to merge them into one.
1. lib/Transforms/Utils/Local.cpp : MergeBasicBlockIntoOnlyPred
2. lib/Transforms/Utils/BasicBlockUtils.cpp : MergeBlockIntoPredecessor

Prior to the patch:
1. MergeBasicBlockIntoOnlyPred
Updates either DomTree or DeferredDominance
Moves all instructions from Pred to BB, deletes Pred
Asserts BB has single predecessor
If address was taken, replace the block address with constant 1 (?)

2. MergeBlockIntoPredecessor
Updates DomTree, LoopInfo and MemoryDependenceResults
Moves all instruction from BB to Pred, deletes BB
Returns if doesn't have a single predecessor
Returns if BB's address was taken

After the patch:
Method 2. MergeBlockIntoPredecessor is attempting to become the new default:
Updates DomTree or DeferredDominance, and LoopInfo and MemoryDependenceResults
Moves all instruction from BB to Pred, deletes BB
Returns if doesn't have a single predecessor
Returns if BB's address was taken

Uses of MergeBasicBlockIntoOnlyPred that need to be replaced:

1. lib/Transforms/Scalar/LoopSimplifyCFG.cpp
Updated in this patch. No challenges.

2. lib/CodeGen/CodeGenPrepare.cpp
Updated in this patch.
  i. eliminateFallThrough is straightforward, but I added using a temporary array to avoid the iterator invalidation.
  ii. eliminateMostlyEmptyBlock(s) methods also now use a temporary array for blocks
Some interesting aspects:
  - Since Pred is not deleted (BB is), the entry block does not need updating.
  - The entry block was being updated with the deleted block in eliminateMostlyEmptyBlock. Added assert to make obvious that BB=SinglePred.
  - isMergingEmptyBlockProfitable assumes BB is the one to be deleted.
  - eliminateMostlyEmptyBlock(BB) does not delete BB on one path, it deletes its unique predecessor instead.
  - adding some test owner as subscribers for the interesting tests modified:
    test/CodeGen/X86/avx-cmp.ll
    test/CodeGen/AMDGPU/nested-loop-conditions.ll
    test/CodeGen/AMDGPU/si-annotate-cf.ll
    test/CodeGen/X86/hoist-spill.ll
    test/CodeGen/X86/2006-11-17-IllegalMove.ll

3. lib/Transforms/Scalar/JumpThreading.cpp
Not covered in this patch. It is the only use case using the DeferredDominance.
I would defer to Brian Rzycki to make this replacement.

Reviewers: chandlerc, spatel, davide, brzycki, bkramer, javed.absar

Subscribers: qcolombet, sanjoy, nemanjai, nhaehnle, jlebar, tpr, kbarton, RKSimon, wmi, arsenm, llvm-commits

Differential Revision: https://reviews.llvm.org/D48202

llvm-svn: 335183
2018-06-20 22:01:04 +00:00
Nirav Dave 3264c1bdf6 [DAG, X86] Revert r327197 "Revert r327170, r327171, r327172"
Reland ISel cycle checking improvements after simplifying node id
invariant traversal and correcting typo.

llvm-svn: 327898
2018-03-19 20:19:46 +00:00
Nirav Dave 5f0ab71b62 Revert "[DAG, X86] Revert r327197 "Revert r327170, r327171, r327172""
as it times out building test-suite on PPC.

llvm-svn: 327778
2018-03-17 19:24:54 +00:00
Nirav Dave 982d3a56ea [DAG, X86] Revert r327197 "Revert r327170, r327171, r327172"
Reland ISel cycle checking improvements after simplifying and reducing
node id invariant traversal.

llvm-svn: 327777
2018-03-17 17:42:10 +00:00
Nirav Dave 042678bd55 Revert: r327172 "Correct load-op-store cycle detection analysis"
r327171 "Improve Dependency analysis when doing multi-node Instruction Selection"
        r328170 "[DAG] Enforce stricter NodeId invariant during Instruction selection"

Reverting patch as NodeId invariant change is causing pathological
increases in compile time on PPC

llvm-svn: 327197
2018-03-10 02:16:15 +00:00
Nirav Dave d668f69ee7 Improve Dependency analysis when doing multi-node Instruction Selection
Relanding after fixing NodeId Invariant.

Cleanup cycle/validity checks in ISel (IsLegalToFold,
HandleMergeInputChains) and X86 (isFusableLoadOpStore). Now do a full
search for cycles / dependencies pruning the search when topological
property of NodeId allows.

As part of this propogate the NodeId-based cutoffs to narrow
hasPreprocessorHelper searches.

Reviewers: craig.topper, bogner

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D41293

llvm-svn: 327171
2018-03-09 20:57:42 +00:00
Chandler Carruth a1d6107b14 [DAG, X86] Revert r324797, r324491, and r324359.
Sadly, r324359 caused at least PR36312. There is a patch out for review
but it seems to be taking a bit and we've already had these crashers in
tree for too long. We're hitting this PR in real code now and are
blocked on shipping new compilers as a consequence so I'm reverting us
back to green.

Sorry for the churn due to the stacked changes that I had to revert. =/

llvm-svn: 325420
2018-02-17 02:26:25 +00:00
Nirav Dave 27721e8617 [DAG, X86] Improve Dependency analysis when doing multi-node
Instruction Selection

Cleanup cycle/validity checks in ISel (IsLegalToFold,
HandleMergeInputChains) and X86 (isFusableLoadOpStore). Now do a full
search for cycles / dependencies pruning the search when topological
property of NodeId allows.

As part of this propogate the NodeId-based cutoffs to narrow
hasPreprocessorHelper searches.

Reviewers: craig.topper, bogner

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D41293

llvm-svn: 324359
2018-02-06 16:14:29 +00:00
Craig Topper b70ca5060f [X86] Teach LowerBUILD_VECTOR to recognize pair-wise splats of 32-bit elements and use a 64-bit broadcast
If we are splatting pairs of 32-bit elements, we can use a 64-bit broadcast to get the job done.

We could probably could probably do this with other sizes too, for example four 16-bit elements. Or we could broadcast pairs of 16-bit elements using a 32-bit element broadcast. But I've left that as a future improvement.

I've also restricted this to AVX2 only because we can only broadcast loads under AVX.

Differential Revision: https://reviews.llvm.org/D42086

llvm-svn: 322730
2018-01-17 18:58:22 +00:00
Francis Visoiu Mistrih 25528d6de7 [CodeGen] Unify MBB reference format in both MIR and debug output
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

llvm-svn: 319665
2017-12-04 17:18:51 +00:00
Craig Topper a5af4a64d0 [AVX512] Don't mark EXTLOAD as legal with AVX512. Continue using custom lowering.
Summary:
This was impeding our ability to combine the extending shuffles with other shuffles as you can see from the test changes.

There's one special case that needed to be added to use VZEXT directly for v8i8->v8i64 since the custom lowering requires v64i8.

Reviewers: RKSimon, zvi, delena

Reviewed By: delena

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D38714

llvm-svn: 315860
2017-10-15 16:41:17 +00:00
Craig Topper bb0e316dc7 [X86] Add broadcast patterns that allow a scalar_to_vector between the broadcast and the load.
We already have these patterns for AVX512VL, but not AVX1 or 2.

llvm-svn: 315382
2017-10-10 22:40:31 +00:00
Reid Kleckner ab23dace56 [MC] Suppress .Lcfi labels when emitting textual assembly
Summary:
This suppresses the generation of .Lcfi labels in our textual assembler.
It was annoying that this generated cascading .Lcfi labels:
  llc foo.ll -o - | llvm-mc | llvm-mc

After three trips through MCAsmStreamer, we'd have three labels in the
output when none are necessary. We should only bother creating the
labels and frame data when making a real object file.

This supercedes D38605, which moved the entire .seh_ implementation into
MCObjectStreamer.

This has the advantage that we do more checking when emitting textual
assembly, as a minor efficiency cost. Outputting textual assembly is not
performance critical, so this shouldn't matter.

Reviewers: majnemer, MatzeB

Subscribers: qcolombet, nemanjai, javed.absar, eraman, hiraditya, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D38638

llvm-svn: 315259
2017-10-10 00:57:36 +00:00
Simon Pilgrim cf99d069c3 [X86][SSE] Add support for decoding PACKSS/PACKUS shuffles masks with UNDEF
llvm-svn: 314792
2017-10-03 12:41:39 +00:00
Simon Pilgrim f5f291d129 [X86][SSE] Add support for lowering shuffles to PACKSS/PACKUS
If the upper bits of a truncation shuffle patterns have at least the minimum number of sign/zero bits on their inputs then we can safely use PACKSS/PACKUS as shuffles.

Partial fix for https://bugs.llvm.org/show_bug.cgi?id=34773

Differential Revision: https://reviews.llvm.org/D38472

llvm-svn: 314788
2017-10-03 12:01:31 +00:00
Simon Pilgrim 037f6d10d5 Regenerate test. NFCI.
llvm-svn: 314679
2017-10-02 15:16:30 +00:00
Nikolai Bozhenov 84af99b3b1 [X86FixupBWInsts] More precise register liveness if no <imp-use> on MOVs.
Summary:
Subregister liveness tracking is not implemented for X86 backend, so
sometimes the whole super register is said to be live, when only a
subregister is really live. That might happen if the def and the use
are located in different MBBs, see added fixup-bw-isnt.mir test.

However, using knowledge of the specific instructions handled by the
bw-fixup-pass we can get more precise liveness information which this
change does.

Reviewers: MatzeB, DavidKreitzer, ab, andrew.w.kaylor, craig.topper

Reviewed By: craig.topper

Subscribers: n.bozhenov, myatsina, llvm-commits, hiraditya

Patch by Andrei Elovikov <andrei.elovikov@intel.com>

Differential Revision: https://reviews.llvm.org/D37559

llvm-svn: 313524
2017-09-18 10:17:59 +00:00
Dinar Temirbulatov a0beedef1c [X86] SET0 to use XMM registers where possible PR26018 PR32862
Differential Revision: https://reviews.llvm.org/D35965

llvm-svn: 309926
2017-08-03 08:50:18 +00:00
Dinar Temirbulatov aead31a36f [X86] SET0 to use XMM registers where possible PR26018 PR32862
Differential Revision: https://reviews.llvm.org/D35839

llvm-svn: 309298
2017-07-27 17:47:01 +00:00
Simon Pilgrim c402839c72 [X86][AVX2] Regenerated and cleaned up broadcast tests.
llvm-svn: 309099
2017-07-26 10:47:51 +00:00
Craig Topper ad140cfb68 [X86] Add comment string for broadcast loads from the constant pool.
Summary:
When broadcasting from the constant pool its useful to print out the final vector similar to what we do for normal moves from the constant pool.

I changed only a couple tests that were broadcast focused. One of them had been previously hand tweaked after running the script so that it could check the constant pool declaration. But I think this patch makes that unnecessary now since we can check the comment instead.

Reviewers: spatel, RKSimon, zvi

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34923

llvm-svn: 307062
2017-07-04 05:46:11 +00:00
Sanjay Patel 44e3d4c812 x86] adjust test constants to maintain coverage; NFC
Increment (add 1) could be transformed to sub -1, and we'd lose coverage for these patterns.

llvm-svn: 305646
2017-06-18 14:45:23 +00:00
Michael Kuperstein 6129887d21 [X86] Revert r299387 due to AVX legalization infinite loop.
llvm-svn: 299720
2017-04-06 22:33:25 +00:00
Simon Pilgrim af33757b5d [X86][SSE]] Lower BUILD_VECTOR with repeated elts as BUILD_VECTOR + VECTOR_SHUFFLE
It can be costly to transfer from the gprs to the xmm registers and can prevent loads merging.

This patch splits vXi16/vXi32/vXi64 BUILD_VECTORS that use the same operand in multiple elements into a BUILD_VECTOR with only a single insertion of each of those elements and then performs an unary shuffle to duplicate the values.

There are a couple of minor regressions this patch unearths due to some missing MOVDDUP/BROADCAST folds that I will address in a future patch.

Note: Now that vector shuffle lowering and combining is pretty good we should be reusing that instead of duplicating so much in LowerBUILD_VECTOR - this is the first of several patches to address this.

Differential Revision: https://reviews.llvm.org/D31373

llvm-svn: 299387
2017-04-03 21:06:51 +00:00
Simon Pilgrim 1d8235a022 Regenerate tests to remove duplicated checks
llvm-svn: 298801
2017-03-26 10:28:39 +00:00
Amjad Aboud 4f97751798 [X86] Generate VZEROUPPER for Skylake-avx512.
VZEROUPPER should not be issued on Knights Landing (KNL), but on Skylake-avx512 it should be.

Differential Revision: https://reviews.llvm.org/D29874

llvm-svn: 296859
2017-03-03 09:03:24 +00:00
Craig Topper fe25988c68 [AVX-512] Fix the execution domain for AVX-512 integer broadcasts.
llvm-svn: 296290
2017-02-26 06:45:51 +00:00
Craig Topper fa875a1d3d [AVX-512] Teach EVEX to VEX conversion pass to handle VINSERT and VEXTRACT instructions.
llvm-svn: 290869
2017-01-03 05:46:18 +00:00
Craig Topper 15d116ab41 [AVX-512] Re-generate tests that were updated for r290663 without using update_llc_test_checks.py so duplicate check lines weren't merged.
llvm-svn: 290868
2017-01-03 05:46:10 +00:00
Gadi Haber 19c4fc5e62 This is a large patch for X86 AVX-512 of an optimization for reducing code size by encoding EVEX AVX-512 instructions using the shorter VEX encoding when possible.
There are cases of AVX-512 instructions that have two possible encodings. This is the case with instructions that use vector registers with low indexes of 0 - 15 and do not use the zmm registers or the mask k registers.
The EVEX encoding prefix requires 4 bytes whereas the VEX prefix can take only up to 3 bytes. Consequently, using the VEX encoding for these instructions results in a code size reduction of ~2 bytes even though it is compiled with the AVX-512 features enabled.

Reviewers: Craig Topper, Zvi Rackoover, Elena Demikhovsky 
Differential Revision: https://reviews.llvm.org/D27901

llvm-svn: 290663
2016-12-28 10:12:48 +00:00
Simon Pilgrim d7518896ff [X86][SSE] Fix domains for VZEXT_LOAD type instructions
Add the missing domain equivalences for movss, movsd, movd and movq zero extending loading instructions.

Differential Revision: https://reviews.llvm.org/D27684

llvm-svn: 289825
2016-12-15 16:05:29 +00:00
Simon Pilgrim 8893bd95f0 [X86][SSE] Consistently set MOVD/MOVQ load/store/move instructions to integer domain
We are being inconsistent with these instructions (and all their variants.....) with a random mix of them using the default float domain.

Differential Revision: https://reviews.llvm.org/D27419

llvm-svn: 288902
2016-12-07 12:10:49 +00:00
Matthias Braun 39c3c89cdc MCStreamer: Use "cfi" for CFI related temp labels.
Choosing a "cfi" name makes the intend a bit clearer in an assembly dump
and more importantly the assembly dumps are slightly more stable as the
numbers don't move around anymore when unrelated code calls
createTempSymbol() more or less often.
As they are temp labels the name doesn't influence the generated object
code.

Differential Revision: https://reviews.llvm.org/D27244

llvm-svn: 288290
2016-11-30 23:48:26 +00:00
Simon Pilgrim 2228f70a85 [X86][SSE] Add initial support for combining (V)PMOVZX with shuffles.
llvm-svn: 288049
2016-11-28 17:58:19 +00:00
Craig Topper 5eb5ade894 [X86] Cleanup patterns for using VMOVDDUP for broadcasts.
-Remove OptForSize. Not all of the backend follows the same rules for creating broadcasts and there is no conflicting pattern.
-Don't stop selecting VEX VMOVDDUP when AVX512 is supported. We need VLX for EVEX VMOVDDUP.
-Only use VMOVDDUP for v2i64 broadcasts if AVX2 is not supported.

llvm-svn: 283020
2016-10-01 07:11:24 +00:00
Craig Topper f91830e6ee [X86] Remove extra FileCheck lines that got left behind in r282688.
llvm-svn: 282689
2016-09-29 06:07:07 +00:00
Craig Topper 7eb0e7ce1f [AVX-512] Replicate pattern from AVX to select VMOVDDUP for (v2f64 (X86VBroadcast f64:)). Add AVX512VL to command line of existing AVX2 test that hits this condition.
llvm-svn: 282688
2016-09-29 05:54:43 +00:00
Simon Pilgrim 7a50c8c2ba [X86][AVX2] Ensure on 32-bit targets that we broadcast f64 types not i64 (PR29101)
llvm-svn: 279622
2016-08-24 12:42:31 +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 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
Dan Gohman 61d15ae4f5 [MC] Use .p2align instead of .align
For historic reasons, the behavior of .align differs between targets.
Fortunately, there are alternatives, .p2align and .balign, which make the
interpretation of the parameter explicit, and which behave consistently across
targets.

This patch teaches MC to use .p2align instead of .align, so that people reading
code for multiple architectures don't have to remember which way each platform
does its .align directive.

Differential Revision: http://reviews.llvm.org/D16549

llvm-svn: 258750
2016-01-26 00:03:25 +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
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 69aa463780 Fix line endings
llvm-svn: 254939
2015-12-07 20:36:00 +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