Commit Graph

19 Commits

Author SHA1 Message Date
Eli Friedman 44cdf771fe [AtomicExpand] Merge cmpxchg success and failure ordering when appropriate.
If we're not emitting separate fences for the success/failure cases, we
need to pass the merged ordering to the target so it can emit the
correct instructions.

For the PowerPC testcase, we end up with extra fences, but that seems
like an improvement over missing fences.  If someone wants to improve
that, the PowerPC backed could be taught to emit the fences after isel,
instead of depending on fences emitted by AtomicExpand.

Fixes https://bugs.llvm.org/show_bug.cgi?id=33332 .

Differential Revision: https://reviews.llvm.org/D103342
2021-06-03 11:34:35 -07:00
Nemanja Ivanovic 61f69153e8 [PowerPC] Sign extend comparison operand for signed atomic comparisons
As of 8dacca943a, we sign extend the atomic loaded
operand for signed subword comparisons. However, the assumption that the other
operand is correctly sign extended doesn't always hold. This patch sign extends
the other operand if it needs to be sign extended.

This is a second fix for https://bugs.llvm.org/show_bug.cgi?id=30451

Differential revision: https://reviews.llvm.org/D94058
2021-01-18 21:19:25 -06:00
Kang Zhang 86e3abc9e6 [PowerPC] Add some InstAlias definitions
Summary:
This patch add the InstAlias definitions for below instructions.

ADDI ADDIS ADDI8 ADDIS8
RLWINM8
ISEL ISEL8
OR OR_rec ORI ORI8 XORI8
CNTLZW8 CNTLZW8_rec
TEND TSR
RFEBB
NOR NOR_rec
MTCRF
SUBF SUBF_rec SUBFC SUBFC_rec
RLDICL_32_64
TW

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D77559
2020-05-24 14:05:28 +00:00
Kang Zhang 513976df2e [PowerPC] Ignore implicit register operands for MCInst
Summary:
When doing the conversion: MachineInst -> MCInst, we should ignore the
implicit operands, it will expose more opportunity for InstiAlias.

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D77118
2020-04-16 16:22:43 +00:00
Kang Zhang 8633ef0f43 [PowerPC][UpdateTestChecks] Remove the extra # when scrubbing loop comments
Summary:
The patch D63957 is to avoid empty string when scrubbing loop comments,
it will replace loop comments to a `#`, that's correct.
But if the line has something else not only loop comments, we will get
a extra `#`.
The patch is to remove the extra `#`.

Reviewed By: jsji

Differential Revision: https://reviews.llvm.org/D77357
2020-04-10 06:09:01 +00:00
Kang Zhang 9dcac87297 [NFC][PowerPC] Using update_llc_test_checks.py to update atomics-regression.ll 2020-04-02 12:47:35 +00:00
Jordan Rupprecht f9f81289e6 Revert [MBP] Disable aggressive loop rotate in plain mode
This reverts r369664 (git commit 51f48295cb)

It causes many benchmark regressions, internally and in llvm's benchmark suite.

llvm-svn: 370398
2019-08-29 19:03:58 +00:00
Guozhi Wei 51f48295cb [MBP] Disable aggressive loop rotate in plain mode
Patch https://reviews.llvm.org/D43256 introduced more aggressive loop layout optimization which depends on profile information. If profile information is not available, the statically estimated profile information(generated by BranchProbabilityInfo.cpp) is used. If user program doesn't behave as BranchProbabilityInfo.cpp expected, the layout may be worse.

To be conservative this patch restores the original layout algorithm in plain mode. But user can still try the aggressive layout optimization with -force-precise-rotation-cost=true.

Differential Revision: https://reviews.llvm.org/D65673

llvm-svn: 369664
2019-08-22 16:21:32 +00:00
Hans Wennborg a45f301f7a Revert r368339 "[MBP] Disable aggressive loop rotate in plain mode"
It caused assertions to fire when building Chromium:

  lib/CodeGen/LiveDebugValues.cpp:331: bool
  {anonymous}::LiveDebugValues::OpenRangesSet::empty() const: Assertion
  `Vars.empty() == VarLocs.empty() && "open ranges are inconsistent"' failed.

See https://crbug.com/992871#c3 for how to reproduce.

> Patch https://reviews.llvm.org/D43256 introduced more aggressive loop layout optimization which depends on profile information. If profile information is not available, the statically estimated profile information(generated by BranchProbabilityInfo.cpp) is used. If user program doesn't behave as BranchProbabilityInfo.cpp expected, the layout may be worse.
>
> To be conservative this patch restores the original layout algorithm in plain mode. But user can still try the aggressive layout optimization with -force-precise-rotation-cost=true.
>
> Differential Revision: https://reviews.llvm.org/D65673

llvm-svn: 368579
2019-08-12 14:23:13 +00:00
Guozhi Wei 80347c3acc [MBP] Disable aggressive loop rotate in plain mode
Patch https://reviews.llvm.org/D43256 introduced more aggressive loop layout optimization which depends on profile information. If profile information is not available, the statically estimated profile information(generated by BranchProbabilityInfo.cpp) is used. If user program doesn't behave as BranchProbabilityInfo.cpp expected, the layout may be worse.

To be conservative this patch restores the original layout algorithm in plain mode. But user can still try the aggressive layout optimization with -force-precise-rotation-cost=true.

Differential Revision: https://reviews.llvm.org/D65673

llvm-svn: 368339
2019-08-08 20:25:23 +00:00
Guozhi Wei d2210af332 [MBP] Move a latch block with conditional exit and multi predecessors to top of loop
Current findBestLoopTop can find and move one kind of block to top, a latch block has one successor. Another common case is:

    * a latch block
    * it has two successors, one is loop header, another is exit
    * it has more than one predecessors

If it is below one of its predecessors P, only P can fall through to it, all other predecessors need a jump to it, and another conditional jump to loop header. If it is moved before loop header, all its predecessors jump to it, then fall through to loop header. So all its predecessors except P can reduce one taken branch.

Differential Revision: https://reviews.llvm.org/D43256

llvm-svn: 363471
2019-06-14 23:08:59 +00:00
Stefan Pintilie cb4f0c5c07 [PowerPC] Replace the Post RA List Scheduler with the Machine Scheduler
We want to run the Machine Scheduler instead of the List Scheduler after RA.
  Checked with a performance run on a Power 9 machine with SPEC 2006 and while
  some benchmarks improved and others degraded the geomean was slightly improved
  with the Machine Scheduler.

  Differential Revision: https://reviews.llvm.org/D45265

llvm-svn: 336295
2018-07-04 18:54:25 +00:00
Nemanja Ivanovic ebb23078e9 [PowerPC] Zero-extend the compare operand for ATOMIC_CMP_SWAP
Part of the fix for https://bugs.llvm.org/show_bug.cgi?id=35812.
This patch ensures that the compare operand for the atomic compare and swap
is properly zero-extended to 32 bits if applicable.
A follow-up commit will fix the extension for the SETCC node generated when
expanding an ATOMIC_CMP_SWAP_WITH_SUCCESS. That will complete the bug fix.

Differential Revision: https://reviews.llvm.org/D41856

llvm-svn: 322372
2018-01-12 14:58:41 +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
Hiroshi Inoue ed1ffa49a4 [PowerPC] eliminate unconditional branch to the next instruction
This patch makes analyzeBranch eliminate unconditional branch to the next instruction.
After basic blocks are re-organized by optimizers, such as machine block placement, a BB may end with an unconditional branch to the next (fallthrough) BB. This patch removes such redundant branch instruction.

Differential Revision: https://reviews.llvm.org/D37730

llvm-svn: 314297
2017-09-27 10:33:02 +00:00
Konstantin Zhuravlyov bb80d3e1d3 Enhance synchscope representation
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
  global and local memory. These scopes restrict how synchronization is
  achieved, which can result in improved performance.

  This change extends existing notion of synchronization scopes in LLVM to
  support arbitrary scopes expressed as target-specific strings, in addition to
  the already defined scopes (single thread, system).

  The LLVM IR and MIR syntax for expressing synchronization scopes has changed
  to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
  replaces *singlethread* keyword), or a target-specific name. As before, if
  the scope is not specified, it defaults to CrossThread/System scope.

  Implementation details:
    - Mapping from synchronization scope name/string to synchronization scope id
      is stored in LLVM context;
    - CrossThread/System and SingleThread scopes are pre-defined to efficiently
      check for known scopes without comparing strings;
    - Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
      the bitcode.

Differential Revision: https://reviews.llvm.org/D21723

llvm-svn: 307722
2017-07-11 22:23:00 +00:00
Hiroshi Inoue 7a08bb1458 [PowerPC] fix potential verification errors on CFENCE8
This patch fixes a potential verification error (64-bit register operands for cmpw) with -verify-machineinstrs.

Differential Revision: https://reviews.llvm.org/D34208

llvm-svn: 305479
2017-06-15 16:51:28 +00:00
Tim Shen 3bef27cc6f [PPC] Lower load acquire/seq_cst trailing fence to cmp + bne + isync.
Summary:
This fixes pr32392.

The lowering pipeline is:
llvm.ppc.cfence in IR -> PPC::CFENCE8 in isel -> Actual instructions in
expandPostRAPseudo.

The reason why expandPostRAPseudo is chosen is because previous passes
are likely eliminating instructions like cmpw 3, 3 (early CSE) and bne-
7, .+4 (some branch pass(s)).

Differential Revision: https://reviews.llvm.org/D32763

llvm-svn: 303205
2017-05-16 20:18:06 +00:00
Tim Shen ce26a45f7c [PPC] Add generated tests for all atomic operations
Summary: Add tests for all atomic operations for powerpc64le, so that all changes can be easily examined.

Reviewers: kbarton, hfinkel, echristo

Subscribers: mehdi_amini, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D31285

llvm-svn: 298614
2017-03-23 16:02:47 +00:00