Commit Graph

9 Commits

Author SHA1 Message Date
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
Nemanja Ivanovic e22ebeab1a [PowerPC] Reverting sequence of patches for elimination of comparison instructions
In the past while, I've committed a number of patches in the PowerPC back end
aimed at eliminating comparison instructions. However, this causes some failures
in proprietary source and these issues are not observed in SPEC or any open
source packages I've been able to run.
As a result, I'm pulling the entire series and will refactor it to:
- Have a single entry point for easy control
- Have fine-grained control over which patterns we transform

A side-effect of this is that test cases for these patches (and modified by
them) are XFAIL-ed. This is a temporary measure as it is counter-productive
to remove/modify these test cases and then have to modify them again when
the refactored patch is recommitted.
The failure will be investigated in parallel to the refactoring effort and
the recommit will either have a fix for it or will leave this transformation
off by default until the problem is resolved.

llvm-svn: 314244
2017-09-26 20:42:47 +00:00
Mikael Holmen 8b10680922 [IfConversion] Maintain the CFG when predicating/merging blocks in IfConvert*
Summary:
This fixes PR32721 in IfConvertTriangle and possible similar problems in
IfConvertSimple, IfConvertDiamond and IfConvertForkedDiamond.

In PR32721 we had a triangle

   EBB
   | \
   |  |
   | TBB
   |  /
   FBB

where FBB didn't have any successors at all since it ended with an
unconditional return. Then TBB and FBB were be merged into EBB, but EBB
would still keep its successors, and the use of analyzeBranch and
CorrectExtraCFGEdges wouldn't help to remove them since the return
instruction is not analyzable (at least not on ARM).

The edge updating code and branch probability updating code is now pushed
into MergeBlocks() which allows us to share the same update logic between
more callsites. This lets us remove several dependencies on analyzeBranch
and completely eliminate RemoveExtraEdges.

One thing that showed up with this patch was that IfConversion sometimes
left a successor with 0% probability even if there was no branch or
fallthrough to the successor.

One such example from the test case ifcvt_bad_zero_prob_succ.mir. The
indirect branch tBRIND can only jump to bb.1, but without the patch we
got:

  bb.0:
    successors: %bb.1(0x80000000)

  bb.1:
    successors: %bb.1(0x80000000), %bb.2(0x00000000)
    tBRIND %r1, 1, %cpsr
    B %bb.1

  bb.2:

There is no way to jump from bb.1 to bb2, but still there is a 0% edge
from bb.1 to bb.2.

With the patch applied we instead get the expected:

  bb.0:
    successors: %bb.1(0x80000000)

  bb.1:
    successors: %bb.1(0x80000000)
    tBRIND %r1, 1, %cpsr
    B %bb.1

Since bb.2 had no predecessor at all, it was removed.

Several testcases had to be updated due to this since the removed
successor made the "Branch Probability Basic Block Placement" pass
sometimes place blocks in a different order.

Finally added a couple of new test cases:

* PR32721_ifcvt_triangle_unanalyzable.mir:
  Regression test for the original problem dexcribed in PR 32721.

* ifcvt_triangleWoCvtToNextEdge.mir:
  Regression test for problem that caused a revert of my first attempt
  to solve PR 32721.

* ifcvt_simple_bad_zero_prob_succ.mir:
  Test case showing the problem where a wrong successor with 0% probability
  was previously left.

* ifcvt_[diamond|forked_diamond|simple]_unanalyzable.mir
  Very simple test cases for the simple and (forked) diamond cases
  involving unanalyzable branches that can be nice to have as a base if
  wanting to write more complicated tests.

Reviewers: iteratee, MatzeB, grosser, kparzysz

Reviewed By: kparzysz

Subscribers: kbarton, davide, aemerson, nemanjai, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D34099

llvm-svn: 310697
2017-08-11 06:57:08 +00:00
Nemanja Ivanovic 009016bb70 [PowerPC] Pretty-print CR bits the way the binutils disassembler does
This patch just adds printing of CR bit registers in a more human-readable
form akin to that used by the GNU binutils.

Differential Revision: https://reviews.llvm.org/D31494

llvm-svn: 309001
2017-07-25 18:26:35 +00:00
Nemanja Ivanovic 864c953773 [PowerPC] - Recommit r304907 now that the issue has been fixed
This is just a recommit since the issue that the commit exposed is now
resolved.

llvm-svn: 308995
2017-07-25 17:54:51 +00:00
Nemanja Ivanovic 7855185bbb Revert r304907 as it is causing some failures that I cannot reproduce.
Reverting this until a test case can be provided to aid the investigation.

llvm-svn: 305372
2017-06-14 07:05:42 +00:00
Nemanja Ivanovic d8623f0825 [PowerPC] Eliminate integer compare instructions - vol. 5
Adds handling for i64 SETNE comparison (both sign and zero extended).

Differential Revision: https://reviews.llvm.org/D33720

llvm-svn: 304907
2017-06-07 13:18:06 +00:00
Nemanja Ivanovic accab033c9 [PowerPC] Eliminate integer compare instructions - vol. 3
This patch builds upon https://reviews.llvm.org/rL302810 to add
handling for the 64-bit SETEQ patterns.

Differential Revision: https://reviews.llvm.org/D33369

llvm-svn: 304286
2017-05-31 08:04:07 +00:00
Nemanja Ivanovic e597bd8230 [PowerPC] Eliminate integer compare instructions - vol. 2
This patch builds upon https://reviews.llvm.org/rL302810 to add
handling for bitwise logical operations in general purpose registers.
The idea is to keep the values in GPRs as long as possible - only
extracting them to a condition register bit when no further operations
are to be done.

Differential Revision: https://reviews.llvm.org/D31851

llvm-svn: 304282
2017-05-31 05:40:25 +00:00