Commit Graph

75 Commits

Author SHA1 Message Date
Chandler Carruth a308955993 Refactor the inline cost bonus calculation for constants to use
a worklist rather than a recursive call.

No functionality changed.

llvm-svn: 152706
2012-03-14 07:32:53 +00:00
Benjamin Kramer 71ff880ff9 Make helper static, so it can be inlined into its sole caller.
llvm-svn: 152515
2012-03-10 22:41:06 +00:00
Chandler Carruth 783b7198b7 Undo a previous restriction on the inline cost calculation which Nick
introduced. Specifically, there are cost reductions for all
constant-operand icmp instructions against an alloca, regardless of
whether the alloca will in fact be elligible for SROA. That means we
don't want to abort the icmp reduction computation when we abort the
SROA reduction computation. That in turn frees us from the need to keep
a separate worklist and defer the ICmp calculations.

Use this new-found freedom and some judicious function boundaries to
factor the innards of computing the cost factor of any given instruction
out of the loop over the instructions and into static helper functions.
This greatly simplifies the code, and hopefully makes it more clear what
is happening here.

Reviewed by Eric Christopher. There is some concern that we'd like to
ensure this doesn't get out of hand, and I plan to benchmark the effects
of this change over the next few days along with some further fixes to
the inline cost.

llvm-svn: 152368
2012-03-09 02:49:36 +00:00
Chandler Carruth dd1637c393 Rotate two of the functions used to count bonuses for the inline cost
analysis to be methods on the cost analysis's function info object
instead of the code metrics object. These really are just users of the
code metrics, they're building the information for the function's
analysis.

This is the first step of growing the amount of information we collect
about a function in order to cope with pair-wise simplifications due to
allocas.

llvm-svn: 152283
2012-03-08 02:04:19 +00:00
Nick Lewycky 0e496cddf0 Use precomputed BB size instead of BB->size().
llvm-svn: 148964
2012-01-25 18:54:13 +00:00
Nick Lewycky 70d50ee8fb Support pointer comparisons against constants, when looking at the inline-cost
savings from a pointer argument becoming an alloca. Sometimes callees will even
compare a pointer to null and then branch to an otherwise unreachable block!
Detect these cases and compute the number of saved instructions, instead of
bailing out and reporting no savings.

llvm-svn: 148941
2012-01-25 08:27:40 +00:00
Nick Lewycky e8415fea4b Fix CountCodeReductionForAlloca to more accurately represent what SROA can and
can't handle. Also don't produce non-zero results for things which won't be
transformed by SROA at all just because we saw the loads/stores before we saw
the use of the address.

llvm-svn: 148536
2012-01-20 08:35:20 +00:00
Nick Lewycky c186d07bbe Continue counting intrinsics as instructions (except when they aren't, such as
debug info) and for being vector operations. Fixes regression from r147037.

llvm-svn: 147093
2011-12-21 20:26:03 +00:00
Nick Lewycky 281e2747e0 Fix typo and spacing, no functionality change.
llvm-svn: 147092
2011-12-21 20:21:55 +00:00
Nick Lewycky da22fc6a1d A call to a function marked 'noinline' is not an inline candidate. The sole
call site of an intrinsic is also not an inline candidate. While here, make it
more obvious that this code ignores all intrinsics. Noticed by inspection!

llvm-svn: 147037
2011-12-21 06:06:30 +00:00
Joerg Sonnenberger d6cb7649d8 Allow inlining of functions with returns_twice calls, if they have the
attribute themselve.

llvm-svn: 146851
2011-12-18 20:35:43 +00:00
Eli Friedman 68db4c2699 A FIXME about block addresses and indirectbr.
llvm-svn: 142569
2011-10-20 04:05:33 +00:00
Bill Wendling 63a4ea1859 Correct over-zealous removal of hack.
Some code want to check that *any* call within a function has the 'returns
twice' attribute, not just that the current function has one.

llvm-svn: 142221
2011-10-17 18:43:40 +00:00
Bill Wendling 2a83a71c2a Now that we have the ReturnsTwice function attribute, this method is
obsolete. Check the attribute instead.
<rdar://problem/8031714>

llvm-svn: 142212
2011-10-17 18:22:52 +00:00
Andrew Trick f7656015fc Inlining and unrolling heuristics should be aware of free truncs.
We want heuristics to be based on accurate data, but more importantly
we don't want llvm to behave randomly. A benign trunc inserted by an
upstream pass should not cause a wild swings in optimization
level. See PR11034. It's a general problem with threshold-based
heuristics, but we can make it less bad.

llvm-svn: 140919
2011-10-01 01:39:05 +00:00
Andrew Trick caa500bf93 whitespace
llvm-svn: 140916
2011-10-01 01:27:56 +00:00
Eli Friedman bacb17906a Change condition for determining whether a function is small for inlining metrics so that very long functions
with few basic blocks are not re-analyzed.

llvm-svn: 131994
2011-05-24 20:22:24 +00:00
Rafael Espindola 71f8b08a80 Extra refactoring noticed by Eli Friedman.
llvm-svn: 131405
2011-05-16 15:48:45 +00:00
Chris Lattner 0ab5e2cded Fix a ton of comment typos found by codespell. Patch by
Luis Felipe Strano Moraes!

llvm-svn: 129558
2011-04-15 05:18:47 +00:00
Eric Christopher b54605b8e2 Remove premature optimization that avoided calculating argument weights
if we weren't going to inline the function. The rest of the code using
this was removed.

Fixes PR9154.

llvm-svn: 124991
2011-02-06 21:27:46 +00:00
Eric Christopher ceb4671ddd Fix cut and paste error spotted by Jakob.
llvm-svn: 124930
2011-02-05 02:48:47 +00:00
Eric Christopher 2dfbd7e0c1 Rewrite how the indirect call bonus is handled. This now works by:
a) Making it a per call site bonus for functions that we can move from
indirect to direct calls.
b) Reduces the bonus from 500 to 100 per call site.
c) Subtracts the size of the possible newly inlineable call from the
bonus to only add a bonus if we can inline a small function to devirtualize
it.

Also changes the bonus from a positive that's subtracted to a negative
that's added.

Fixes the remainder of rdar://8546196 by reducing the object file size
after inlining by 84%.

llvm-svn: 124916
2011-02-05 00:49:15 +00:00
Eric Christopher 46308e666a Reapply 124275 since the Dragonegg failure was unreproducible.
llvm-svn: 124641
2011-02-01 01:16:32 +00:00
Eric Christopher cd55a46c31 Temporarily revert 124275 to see if it brings the dragonegg buildbot back.
llvm-svn: 124312
2011-01-26 19:40:31 +00:00
Eric Christopher 078159e310 Separate out the constant bonus from the size reduction metrics. Rework
a few loops accordingly. Should be no functional change.

This is a step for more accurate cost/benefit analysis of devirt/inlining
bonuses.

llvm-svn: 124275
2011-01-26 02:58:39 +00:00
Eric Christopher 58f157a677 Coding style formatting changes.
llvm-svn: 124260
2011-01-26 01:09:59 +00:00
Eric Christopher cd087f2512 Reorganize this so that the early exit and special cases come early
rather than interspersed. No functional change.

llvm-svn: 124168
2011-01-25 01:34:31 +00:00
Eric Christopher c70e037b73 Add a FIXME explaining the move to a single indirect call bonus per function
that we can change from indirect to direct.

llvm-svn: 124045
2011-01-22 21:56:53 +00:00
Eric Christopher 08e8b3b629 Only apply the devirtualization bonus once instead of per-call site in the
target function.

Fixes part of rdar://8546196

llvm-svn: 124044
2011-01-22 21:17:33 +00:00
Kenneth Uildriks b8d7efe785 Now using a variant of the existing inlining heuristics to decide whether to create a given specialization of a function in PartialSpecialization. If the total performance bonus across all callsites passing the same constant exceeds the specialization cost, we create the specialization.
llvm-svn: 116158
2010-10-09 22:06:36 +00:00
Kenneth Uildriks 99463ca8cf Start separating out code metrics into code size metrics and code performance metrics. Partial Specialization will apply the former to function specializations, and the latter to all callsites that can use a specialization, in order to decide whether to create a specialization
llvm-svn: 116057
2010-10-08 13:57:31 +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 a08318acb2 Refactor code-size reduction estimation methods out of InlineCostAnalyzer and into CodeMetrics. They
don't use any InlineCostAnalyzer state, and are useful for other clients who don't necessarily want to use
all of InlineCostAnalyzer's logic, some of which is fairly inlining-specific.

No intended functionality change.

llvm-svn: 113499
2010-09-09 16:56:42 +00:00
Gabor Greif d59498bc97 use ImmutableCallSite for const-corrgoodness
llvm-svn: 109503
2010-07-27 14:15:29 +00:00
Kenneth Uildriks 9b21208bfb Pulled CodeMetrics out of InlineCost.h and made it a bit more general, so it can be reused from PartialSpecializationCost
llvm-svn: 105725
2010-06-09 15:11:37 +00:00
Jakob Stoklund Olesen d67defdfe2 Avoid counting InlineAsm as a call - it prevents loop unrolling.
PR7026
Patch by Pekka Jääskeläinen!

llvm-svn: 104780
2010-05-26 22:40:28 +00:00
Nick Lewycky c63aa1e8ab Clear CachedFunctionInfo upon Pass::releaseMemory. Because ValueMap will abort
on RAUW of functions, this is a correctness issue instead of a mere memory
usage problem.


No testcase until the new MergeFunctions can land.

llvm-svn: 103653
2010-05-12 21:48:15 +00:00
David Chisnall f4b87f191b Added a variant of InlineCostAnalyzer::getInlineCost() that takes the called function as an explicit argument, for use when inlining function pointers.
llvm-svn: 102841
2010-05-01 15:47:41 +00:00
Chris Lattner a9bac86d16 Dan recently disabled recursive inlining within a function, but we
were still inlining self-recursive functions into other functions.

Inlining a recursive function into itself has the potential to
reduce recursion depth by a factor of 2, inlining a recursive
function into something else reduces recursion depth by exactly 
1.  Since inlining a recursive function into something else is a
weird form of loop peeling, turn this off.

The deleted testcase was added by Dale in r62107, since then
we're leaning towards not inlining recursive stuff ever.  In any
case, if we like inlining recursive stuff, it should be done 
within the recursive function itself to get the algorithm 
recursion depth win.

llvm-svn: 102798
2010-04-30 22:37:22 +00:00
Dan Gohman 4398308fa7 Revert r101471. For tight recursive functions which have multiple
recursive callsites, inlining can reduce the number of calls by
exponential factors, as it does in
MultiSource/Benchmarks/Olden/treeadd. More involved heuristics
will be needed.

llvm-svn: 101969
2010-04-21 00:43:30 +00:00
Chris Lattner 67e70971cc fix PR6858: a dangling pointer use bug which was caused
by switching CachedFunctionInfo from a std::map to a 
ValueMap (which is implemented in terms of a DenseMap).

DenseMap has different iterator invalidation semantics
than std::map.

This should hopefully fix the dragonegg builder.

llvm-svn: 101658
2010-04-17 17:57:56 +00:00
Chris Lattner cea19a475b a bunch of cleanups and tweaks, no functionality changes.
llvm-svn: 101657
2010-04-17 17:55:00 +00:00
Dan Gohman f13f69f296 Disable inlining of recursive calls. It can complicate tailcallelim and
dependent analyses, and increase code size, so doing it profitably would
require more complex heuristics.

llvm-svn: 101471
2010-04-16 16:01:18 +00:00
Dan Gohman b3862ecd48 Make callIsSmall accessible as a utility function.
llvm-svn: 101463
2010-04-16 15:14:50 +00:00
Gabor Greif fefdd42644 performance: cache the dereferenced use_iterator
llvm-svn: 101265
2010-04-14 18:13:29 +00:00
Eric Christopher b1a382d8b9 Reapply r99451 with a fix to move the NoInline check to the cost functions
instead of InlineFunction.

llvm-svn: 99483
2010-03-25 04:49:10 +00:00
Duncan Sands 145584e037 Treat copysignl like the other copysign functions.
llvm-svn: 98542
2010-03-15 14:01:44 +00:00
Devang Patel 93142469ac Do not ignore arg_size() impact while counting bb instructions.
llvm-svn: 98408
2010-03-13 01:05:02 +00:00
Devang Patel 877d0355bd Remove extra parameter.
llvm-svn: 98403
2010-03-13 00:45:31 +00:00
Devang Patel ad591dc6af Do not overestimate code size reduction in presense of debug info.
Use CodeMetrics.analyzeBasicBlock() to estimate BB size.

llvm-svn: 98401
2010-03-13 00:10:20 +00:00