Commit Graph

33 Commits

Author SHA1 Message Date
Chris Lattner 35a65b2aa6 fix a couple -Wsign-compare warnings.
llvm-svn: 129501
2011-04-14 02:27:25 +00:00
Junjie Gu 377cc31a74 Fixed the revision 129449.
llvm-svn: 129450
2011-04-13 16:45:49 +00:00
Junjie Gu 7c3b4593b5 Passing unroll parameters (unroll-count, threshold, and partial unroll) via LoopUnroll class's ctor. Doing so
will allow multiple context with different loop unroll parameters to run.  This is a minor change and no effect 
on existing application.

llvm-svn: 129449
2011-04-13 16:15:29 +00:00
Owen Anderson 459e079912 Remove dead code, that I apparently wrote a while back. We seem to be doing well enough
without whatever this was trying to do.  When/if someone has the time to do some empirical
evaluations, it might be worth it to figure out what this code was trying to do and see if
it's worth resurrecting/fixing.

llvm-svn: 123684
2011-01-17 22:39:54 +00:00
Chris Lattner dfcfcb49fa random cleanups
llvm-svn: 123221
2011-01-11 08:00:40 +00:00
Chris Lattner 679572e584 improve loop rotation to use CodeMetrics to analyze the
size of a loop header instead of its own code size estimator.
This allows it to handle bitcasts etc more precisely.

llvm-svn: 122681
2011-01-02 07:35:53 +00:00
Owen Anderson a4fefc1949 Passes do not need to recursively initialize passes that they preserve, if
they do not also require them.  This allows us to reduce inter-pass linkage
dependencies.

llvm-svn: 116854
2010-10-19 20:08:44 +00:00
Owen Anderson 6c18d1aac0 Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which
must be called in the pass's constructor.  This function uses static dependency declarations to recursively initialize
the pass's dependencies.

Clients that only create passes through the createFooPass() APIs will require no changes.  Clients that want to use the
CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h
before parsing commandline arguments.

I have tested this with all standard configurations of clang and llvm-gcc on Darwin.  It is possible that there are problems
with the static dependencies that will only be visible with non-standard options.  If you encounter any crash in pass
registration/creation, please send the testcase to me directly.

llvm-svn: 116820
2010-10-19 17:21:58 +00:00
Owen Anderson 8ac477ffb5 Begin adding static dependence information to passes, which will allow us to
perform initialization without static constructors AND without explicit initialization
by the client.  For the moment, passes are required to initialize both their
(potential) dependencies and any passes they preserve.  I hope to be able to relax
the latter requirement in the future.

llvm-svn: 116334
2010-10-12 19:48:12 +00:00
Owen Anderson df7a4f2515 Now with fewer extraneous semicolons!
llvm-svn: 115996
2010-10-07 22:25:06 +00:00
Owen Anderson d67ca0ed4c Revert r114919, which caused some serious regressions on ARM.
llvm-svn: 115053
2010-09-29 18:05:19 +00:00
Owen Anderson 9c93fd5598 Weight loop unrolling counts by nesting depth. Unrolling deeply nested loops tends to cause high
register pressure and thus excess spills, which we don't currently recover from well.  This should
be re-evaluated in the future if our ability to generate good spills/splits improves.

Partial fix for <rdar://problem/7635585>.

llvm-svn: 114919
2010-09-27 22:58:54 +00:00
Owen Anderson d85c9ccdba Lower the unrolling theshold to 150. Empirical tests indicate that this is a sweet spot in the performance per
code size increase curve.

llvm-svn: 113595
2010-09-10 17:57:00 +00:00
Owen Anderson 04cf3fd761 What the loop unroller cares about, rather than just not unrolling loops with calls, is
not unrolling loops that contain calls that would be better off getting inlined.  This mostly
comes up when an interleaved devirtualization pass has devirtualized a call which the inliner
will inline on a future pass.  Thus, rather than blocking all loops containing calls, add
a metric for "inline candidate calls" and block loops containing those instead.

llvm-svn: 113535
2010-09-09 20:32:23 +00:00
Owen Anderson 6270515918 Revert r113439, which relaxed the requirement that loops containing calls cannot be unrolled. After some discussion,
there seems to be a better way to achieve the same effect.

llvm-svn: 113528
2010-09-09 20:02:23 +00:00
Owen Anderson 11ab204fdc r113526 introduced an unintended change to the loop unrolling threshold. Revert it.
llvm-svn: 113527
2010-09-09 19:11:57 +00:00
Owen Anderson b61b1647e2 Fix typo in code to cap the loop code size reduction calculation.
llvm-svn: 113526
2010-09-09 19:08:59 +00:00
Owen Anderson 62ea1b718c Use code-size reduction metrics to estimate the amount of savings we'll get when we unroll a loop.
Next step is to recalculate the threshold values given this new heuristic.

llvm-svn: 113525
2010-09-09 19:07:31 +00:00
Owen Anderson 8084dbaf8e Relax the "don't unroll loops containing calls" rule. Instead, when a loop contains a call, lower the
unrolling threshold to the optimize-for-size threshold.  Basically, for loops containing calls, unrolling
can still be profitable as long as the loop is REALLY small.

llvm-svn: 113439
2010-09-08 23:10:07 +00:00
Owen Anderson a4d9c78aa1 Add a separate unrolling threshold when the current function is being optimized for size.
The threshold value of 50 is arbitrary, and I chose it simply by analogy to the inlining thresholds, where
the baseline unrolling threshold is slightly smaller than the baseline inlining threshold.  This could
undoubtedly use some tuning.

llvm-svn: 113306
2010-09-07 23:15:30 +00:00
Chris Lattner d6f46b8af8 now that loop passes don't use DomFrontier, there is no reason
for the unroller to pretend it supports updating it.  It still
has a horrible hack for DomTree.

llvm-svn: 112444
2010-08-29 17:21:35 +00:00
Owen Anderson a7aed18624 Reapply r110396, with fixes to appease the Linux buildbot gods.
llvm-svn: 110460
2010-08-06 18:33:48 +00:00
Owen Anderson bda59bd247 Revert r110396 to fix buildbots.
llvm-svn: 110410
2010-08-06 00:23:35 +00:00
Owen Anderson 755aceb5d0 Don't use PassInfo* as a type identifier for passes. Instead, use the address of the static
ID member as the sole unique type identifier.  Clean up APIs related to this change.

llvm-svn: 110396
2010-08-05 23:42:04 +00:00
Owen Anderson 9f2bca02d7 Experiments show that we can safely increase our unrolling threshold without unduly impacting code size, particularly
since unrolling is not enabled at -Os.

llvm-svn: 110233
2010-08-04 18:32:46 +00:00
Dan Gohman 0141c13b22 Remove LCSSA's bogus dependence on LoopSimplify and LoopSimplify's bogus
dependence on DominanceFrontier. Instead, add an explicit DominanceFrontier
pass in StandardPasses.h to ensure that it gets scheduled at the right
time.

Declare that loop unrolling preserves ScalarEvolution, and shuffle some
getAnalysisUsages.

This eliminates one LoopSimplify and one LCCSA run in the standard
compile opts sequence.

llvm-svn: 109413
2010-07-26 18:11:16 +00:00
Owen Anderson a57b97e7e7 Fix batch of converting RegisterPass<> to INTIALIZE_PASS().
llvm-svn: 109045
2010-07-21 22:09:45 +00:00
Dan Gohman 2734ebd37f Add a DominatorTree argument to isLCSSA so that it doesn't have to
compute a set of reachable blocks for itself each time it is called, which
is fairly frequently.

llvm-svn: 98179
2010-03-10 19:38:49 +00:00
Jakob Stoklund Olesen 5f9ead2714 Don't unroll loops containing function calls.
llvm-svn: 95454
2010-02-05 23:21:31 +00:00
David Greene e0b9789593 Change errs() to dbgs().
llvm-svn: 92623
2010-01-05 01:27:44 +00:00
Dan Gohman 969e83a4ff Replace LoopUnrollPass.cpp's custom code-size estimation code using
the new common CodeMetrics code.

llvm-svn: 85663
2009-10-31 14:54:17 +00:00
Dan Gohman af94015c18 Remove an unnecessary #include.
llvm-svn: 85661
2009-10-31 14:39:43 +00:00
Dan Gohman f70e76c435 Rename UnrollLoop.cpp to LoopUnroll.cpp, and LoopUnroll.cpp to
LoopUnrollPass.cpp, for consistency with other passes which are
similarly split.

llvm-svn: 85659
2009-10-31 14:37:31 +00:00