Commit Graph

629 Commits

Author SHA1 Message Date
Dan Gohman 49d638b45a Use size_t for consistency.
llvm-svn: 116009
2010-10-07 23:37:58 +00:00
Dan Gohman 8e72611058 When merging one use into another, transfer the offsets from
the old use to the new one.

llvm-svn: 116008
2010-10-07 23:36:45 +00:00
Dan Gohman a7b68d6d95 Fix LSR to keep the RegUseTracker up to date when combining users.
This doesn't usually matter, because the other heuristics usually
succeed regardless, but it's good to keep the register use
bookkeeping consistent.

llvm-svn: 116005
2010-10-07 23:33:43 +00:00
Owen Anderson df7a4f2515 Now with fewer extraneous semicolons!
llvm-svn: 115996
2010-10-07 22:25:06 +00:00
Dan Gohman 16ef49686c Delete an unused function.
llvm-svn: 114841
2010-09-27 16:58:21 +00:00
Gabor Greif a06741b356 do not rely on the implicit-dereference semantics of dyn_cast_or_null
llvm-svn: 114278
2010-09-18 11:55:34 +00:00
Dan Gohman 110ed64fbb Revert 112442 and 112440 until the compile time problems introduced
by 112440 are resolved.

llvm-svn: 112692
2010-09-01 01:45:53 +00:00
Dan Gohman 002ff89cbd Optionally rerun dedicated-register filtering after applying
other filtering techniques, as those may allow it to filter
out more obviously unprofitable candidates.

llvm-svn: 112441
2010-08-29 16:39:22 +00:00
Dan Gohman f031792cc6 Fix several areas in LSR to do a better job keeping the main
LSRInstance data structures up to date. This fixes some
pessimizations caused by stale data which will be exposed
in an upcoming change.

llvm-svn: 112440
2010-08-29 16:32:54 +00:00
Dan Gohman e9e0873b08 Refactor the three main groups of code out of
NarrowSearchSpaceUsingHeuristics into separate functions.

llvm-svn: 112439
2010-08-29 16:09:42 +00:00
Dan Gohman 37a0f68036 Delete a bogus check.
llvm-svn: 112438
2010-08-29 15:30:29 +00:00
Dan Gohman b6a520d63c Add some comments.
llvm-svn: 112437
2010-08-29 15:27:08 +00:00
Dan Gohman bf673e0652 Move this debug output into GenerateAllReuseFormula, to declutter
the high-level logic.

llvm-svn: 112436
2010-08-29 15:21:38 +00:00
Dan Gohman d366b6d5c8 Delete an unused declaration.
llvm-svn: 112435
2010-08-29 15:19:11 +00:00
Dan Gohman 4f13bbfefc Do one lookup instead of two.
llvm-svn: 112434
2010-08-29 15:18:49 +00:00
Dan Gohman 129a816ee6 Process the step before the start, because it's usually the simpler
of the two.

llvm-svn: 111495
2010-08-19 01:02:31 +00:00
Dan Gohman 89fdbaf99a Instead of having CollectSubexpr's categorize operands as interesting or
uninteresting, just put all the operands on one list and make
GenerateReassociations make the decision about what's interesting.
This is simpler, and it avoids an extra ScalarEvolution::getAddExpr call.

llvm-svn: 111133
2010-08-16 15:50:00 +00:00
Dan Gohman 9b7632df26 Put add operands in ScalarEvolution-canonical order, when convenient.
This isn't necessary, because ScalarEvolution sorts them anyway,
but it's tidier this way.

llvm-svn: 111132
2010-08-16 15:39:27 +00:00
Dan Gohman 081ffcd00b Fix LSR's ExtractImmediate and ExtractSymbol to avoid calling
ScalarEvolution::getAddExpr, which can be pretty expensive, when nothing
has changed, which is pretty common.

llvm-svn: 111042
2010-08-13 21:17:19 +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
Dan Gohman ba81fc16a5 Fix whitespace.
llvm-svn: 110223
2010-08-04 17:43:57 +00:00
Oscar Fuentes 40b31ad3ee Prefix `next' iterator operation with `llvm::'.
Fixes potential ambiguity problems on VS 2010.

Patch by nobled!

llvm-svn: 110029
2010-08-02 06:00:15 +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 1415208292 Don't merge uses when they are targetting fixup sites with
different widths. In a use with a narrower fixup, formulae
may be wider than the fixup, in which case the high bits
aren't necessarily meaningful, so it isn't safe to reuse
them for uses with wider fixups.

This fixes PR7618, though the testcase is too large for a
reasonable regression test, since it heavily dependes on
hitting LSR's heuristics in a certain way.

llvm-svn: 108455
2010-07-15 20:24:58 +00:00
Dan Gohman a1501b9c50 Use dbgs() instead of errs() in a DEBUG.
llvm-svn: 108453
2010-07-15 20:12:42 +00:00
Dan Gohman 4afd412d6b Watch out for a constant offset cancelling out a base register, forming
a zero. This situation arrises in Fortran code with induction variables
that start at 1 instead of 0. This fixes PR7651.

llvm-svn: 108424
2010-07-15 15:14:45 +00:00
Gabor Greif 8ae3095286 use getArgOperand instead of getOperand
llvm-svn: 107270
2010-06-30 09:15:28 +00:00
Dan Gohman fb9712bdae In GenerateReassociations, don't bother thinking about individual
SCEVUnknown values which are loop-variant, as LSR can't do anything
interesting with these values in any case. This fixes very slow compile
times on loops which have large numbers of such values.

llvm-svn: 106897
2010-06-25 22:32:18 +00:00
Dan Gohman 963b1c142e A few minor micro-optimizations.
llvm-svn: 106764
2010-06-24 16:57:52 +00:00
Dan Gohman 47ddf76d89 Teach getExactSDiv to evaluate x/1 to x up front, as it's a common
enough special case, and it theoretically allows more folding because
it works even when x is unanalyzable.

llvm-svn: 106763
2010-06-24 16:51:25 +00:00
Dan Gohman ab5422200b Fix copy+pasto issues in isMulSExtable.
llvm-svn: 106759
2010-06-24 16:45:11 +00:00
Dan Gohman 1081f1a0f5 Fix OptimizeMax to handle an odd case where one of the max operands
is another max which folds. This fixes PR7454.

llvm-svn: 106594
2010-06-22 23:07:13 +00:00
Dan Gohman dd41bba517 Use A.append(...) instead of A.insert(A.end(), ...) when A is a
SmallVector, and other SmallVector simplifications.

llvm-svn: 106452
2010-06-21 19:47:52 +00:00
Dan Gohman 32655906e4 Add a TODO comment.
llvm-svn: 106397
2010-06-19 21:30:18 +00:00
Dan Gohman 51d00092b6 Include the use kind along with the expression in the key of the
use sharing map. The reconcileNewOffset logic already forces a
separate use if the kinds differ, so incorporating the kind in the
key means we can track more sharing opportunities.

More sharing means fewer total uses to track, which means smaller
problem sizes, which means the conservative throttles don't kick
in as often.

llvm-svn: 106396
2010-06-19 21:29:59 +00:00
Dan Gohman 297fb8b9fc Don't include things in anonymous namespaces that don't need it.
llvm-svn: 106395
2010-06-19 21:21:39 +00:00
Dan Gohman 67b4403101 Don't track users of undef values; they aren't interesting for
register pressure.

llvm-svn: 105501
2010-06-04 23:16:05 +00:00
Dan Gohman 9b48b856ea DominatorTree.getNode can return null for unreachable blocks.
llvm-svn: 104290
2010-05-20 22:46:54 +00:00
Dan Gohman 86110fa2bb Minor code cleanups.
llvm-svn: 104287
2010-05-20 22:25:20 +00:00
Dan Gohman 6295f2ebb8 Make Solve check its own post-condition, to reduce clutter in the
top-level LSRInstance logic.

llvm-svn: 104278
2010-05-20 20:59:23 +00:00
Dan Gohman a4ca28a3ae Add comments.
llvm-svn: 104276
2010-05-20 20:52:00 +00:00
Dan Gohman 927bcaadda More code cleanups. Use iterators instead of indices when indices
aren't needed.

llvm-svn: 104273
2010-05-20 20:33:18 +00:00
Dan Gohman 4c4043cf34 Fix OptimizeShadowIV to set Changed. Change OptimizeLoopTermCond to set
Changed directly instead of using a return value.

Rename FilterOutUndesirableDedicatedRegisters's Changed variable to
distinguish it from LSRInstance's Changed member.

llvm-svn: 104269
2010-05-20 20:05:31 +00:00
Dan Gohman 8ec018cedf Add some comments.
llvm-svn: 104268
2010-05-20 20:00:41 +00:00
Dan Gohman 8ce95cc3c5 Simplify this code. Don't do a DomTreeNode lookup for each visited block.
llvm-svn: 104267
2010-05-20 20:00:25 +00:00
Dan Gohman ab5fb7f559 Minor code cleanups.
llvm-svn: 104263
2010-05-20 19:44:23 +00:00
Dan Gohman ee2fea3cd7 When canonicalizing icmp operand order to put the loop invariant
operand on the left, the interesting operand is on the right. This
fixes a bug where LSR was failing to recognize ICmpZero uses,
which led it to be unable to reverse the induction variable in the
attached testcase.

Delete test/CodeGen/X86/stack-color-with-reg-2.ll, because its test
is extremely fragile and hard to meaningfully update.

llvm-svn: 104262
2010-05-20 19:26:52 +00:00
Dan Gohman fdf9874ba7 Set Changed to true when canonicalizing ICmp operand order; even though
it isn't a very interesting change, it's a change nonetheless.

llvm-svn: 104260
2010-05-20 19:16:03 +00:00
Dan Gohman 981563d0ba Rename a variable to avoid shadowing.
llvm-svn: 104234
2010-05-20 16:41:11 +00:00
Dan Gohman 6b733fc189 Minor code simplification.
llvm-svn: 104232
2010-05-20 16:23:28 +00:00
Dan Gohman 80a9608442 Move the code for deleting BaseRegs and LSRUses into helper functions,
and fix a bug that valgrind noticed where the code would std::swap an
element with itself.

llvm-svn: 104225
2010-05-20 15:17:54 +00:00
Dan Gohman 20fab456da Teach LSR how to cope better with unrolled loops on targets where
the addressing modes don't make this trivially easy. This allows
it to avoid falling into the less precise heuristics in more
cases.

llvm-svn: 104186
2010-05-19 23:43:12 +00:00
Dan Gohman beebef4137 Add a comment.
llvm-svn: 104089
2010-05-18 23:55:57 +00:00
Dan Gohman 50f8f2c23d Fix the predicate which checks for non-sensical formulae which have
constants in registers which partially cancel out their immediate fields.

llvm-svn: 104088
2010-05-18 23:48:08 +00:00
Dan Gohman 4cf99b5303 Factor out the code for recomputing an LSRUse's Regs set after some
of its formulae have been removed into a helper function, and also
teach it how to update the RegUseTracker.

llvm-svn: 104087
2010-05-18 23:42:37 +00:00
Dan Gohman a4eca05174 Factor out code for estimating search space complexity into a helper
function.

llvm-svn: 104082
2010-05-18 22:51:59 +00:00
Dan Gohman 63e9015248 Add some more debug output.
llvm-svn: 104080
2010-05-18 22:41:32 +00:00
Dan Gohman f1c7b1b42f Factor out the code for deleting a formula from an LSRUse into
a helper function.

llvm-svn: 104079
2010-05-18 22:39:15 +00:00
Dan Gohman 8aca7ef903 Make some debug output more informative.
llvm-svn: 104078
2010-05-18 22:37:37 +00:00
Dan Gohman 06ab08f795 Print an error message in Formula::print if the HasBaseReg flag
is inconsistent with the BaseRegs field. It's not print's job to
assert on an invalid condition, but it can make one more obvious.

llvm-svn: 104077
2010-05-18 22:35:55 +00:00
Dan Gohman 248c41d108 Rename RegUseTracker's RegUses member to RegUsesMap to avoid
confusion with LSRInstance's RegUses member.

llvm-svn: 104076
2010-05-18 22:33:00 +00:00
Douglas Gregor 6739a89117 Fixes for Microsoft Visual Studio 2010, from Steven Watanabe!
llvm-svn: 103457
2010-05-11 06:17:44 +00:00
Dan Gohman d0800241d2 When pruning candidate formulae out of an LSRUse, update the
LSRUse's Regs set after all pruning is done, rather than trying
to do it on the fly, which can produce an incomplete result.

This fixes a case where heuristic pruning was stripping all
formulae from a use, which led the solver to enter an infinite
loop.

Also, add a few asserts to diagnose this kind of situation.

llvm-svn: 103328
2010-05-07 23:36:59 +00:00
Dan Gohman 1d2ded75e2 Use getConstant instead of getIntegerSCEV. The two are basically the
same, now that getConstant has overloads consistent with ConstantInt::get.

llvm-svn: 102965
2010-05-03 22:09:21 +00:00
Dan Gohman 534ba376f6 Generalize LSR's OptimizeMax to handle the new kinds of max expressions
that indvars may use, now that indvars is recognizing le and ge loops.

llvm-svn: 102235
2010-04-24 03:13:44 +00:00
Dan Gohman 997bbc54d6 Fix LSR to tolerate cases where ScalarEvolution initially
misses an opportunity to fold add operands, but folds them
after LSR has separated them out. This fixes rdar://7886751.

llvm-svn: 102157
2010-04-23 01:55:05 +00:00
Dan Gohman e637ff5e9a Remove the Expr member from IVUsers. Instead of remembering the expression,
just ask ScalarEvolution for it on demand. This helps IVUsers be more robust
in the case of expressions changing underneath it. This fixes PR6862.

llvm-svn: 101819
2010-04-19 21:48:58 +00:00
Dan Gohman 27c8e79839 Delete this code, which is no longer needed.
llvm-svn: 101033
2010-04-12 08:00:22 +00:00
Dan Gohman 607e02b33a When determining a canonical insert position, don't climb deeper
into adjacent loops. Also, ensure that the insert position is
dominated by the loop latch of any loop in the post-inc set which
has a latch.

llvm-svn: 100906
2010-04-09 22:07:05 +00:00
Dan Gohman 42ec4eb351 When looking for loop-invariant users, look through no-op instructions,
so that an unfortunately placed bitcast doesn't pin a value in a
register.

llvm-svn: 100883
2010-04-09 19:12:34 +00:00
Dan Gohman d2df643ddb Refactor the code for computing the insertion point for an expression into
a separate function.

llvm-svn: 100845
2010-04-09 02:00:38 +00:00
Dan Gohman 9b5d0bb774 Avoid allocating a value of zero in a register if the initial formula
inputs happen to negate each other.

llvm-svn: 100828
2010-04-08 23:36:27 +00:00
Dan Gohman 4ce1fb1448 Add variants of ult, ule, etc. which take a uint64_t RHS, for convenience.
llvm-svn: 100824
2010-04-08 23:03:40 +00:00
Dan Gohman 4506539d84 When expanding expressions which are using post-inc mode for multiple loops,
ensure that the expansion is dominated by the increments of those loops.

llvm-svn: 100748
2010-04-08 05:57:57 +00:00
Dan Gohman d006ab90dd Generalize IVUsers to track arbitrary expressions rather than expressions
explicitly split into stride-and-offset pairs. Also, add the
ability to track multiple post-increment loops on the same expression.

This refines the concept of "normalizing" SCEV expressions used for
to post-increment uses, and introduces a dedicated utility routine for
normalizing and denormalizing expressions.

This fixes the expansion of expressions which are post-increment users
of more than one loop at a time. More broadly, this takes LSR another
step closer to being able to reason about more than one loop at a time.

llvm-svn: 100699
2010-04-07 22:27:08 +00:00
Dan Gohman d42e09d91e Ignore debug intrinsics in yet more places.
llvm-svn: 99580
2010-03-26 00:33:27 +00:00
Gabor Greif c78d720f02 rename use_const_iterator to const_use_iterator for consistency's sake
llvm-svn: 99564
2010-03-25 23:06:16 +00:00
Dan Gohman 29707de4fe Make SCEVExpander and LSR more aggressive about hoisting expressions out
of loops.

llvm-svn: 97642
2010-03-03 05:29:13 +00:00
Dan Gohman 52f5563973 Non-affine post-inc SCEV expansions have more code which must be
emitted after the increment. Make sure the insert position
reflects this. This fixes PR6453.

llvm-svn: 97537
2010-03-02 01:59:21 +00:00
Dan Gohman 8b0a419eb1 Spelling fixes.
llvm-svn: 97453
2010-03-01 17:49:51 +00:00
Dan Gohman 8c16b38262 Remove unused variables and parameters.
llvm-svn: 96780
2010-02-22 04:11:59 +00:00
Dan Gohman 4506fcb3c2 When emitting an instruction which depends on both a post-incremented
induction variable value and a loop-variant value, don't force the
insert position to be at the post-increment position, because it may
not be dominated by the loop-variant value. This fixes a
use-before-def problem noticed on PPC.

llvm-svn: 96774
2010-02-22 03:59:54 +00:00
Dan Gohman 4eebb94094 Rename getSDiv to getExactSDiv to reflect its behavior in cases where
the division would have a remainder.

llvm-svn: 96693
2010-02-19 19:35:48 +00:00
Dan Gohman 85af256779 Check for overflow when scaling up an add or an addrec for
scaled reuse.

llvm-svn: 96692
2010-02-19 19:32:49 +00:00
Dan Gohman 2446f57503 When determining the set of interesting reuse factors, consider
strides in foreign loops. This helps locate reuse opportunities
with existing induction variables in foreign loops and reduces
the need for inserting new ones. This fixes rdar://7657764.

llvm-svn: 96629
2010-02-19 00:05:23 +00:00
Dan Gohman 13ac3b2139 Delete some unneeded casts.
llvm-svn: 96429
2010-02-17 00:42:19 +00:00
Dan Gohman 5f10d6c52c Don't attempt to divide INT_MIN by -1; consider such cases to
have overflowed.

llvm-svn: 96428
2010-02-17 00:41:53 +00:00
Dan Gohman 6deab96c81 Refactor rewriting for PHI nodes into a separate function.
llvm-svn: 96382
2010-02-16 20:25:07 +00:00
Dan Gohman 0849ed5e26 Fix whitespace.
llvm-svn: 96372
2010-02-16 19:42:34 +00:00
Duncan Sands 19d0b47b1f There are two ways of checking for a given type, for example isa<PointerType>(T)
and T->isPointerTy().  Convert most instances of the first form to the second form.
Requested by Chris.

llvm-svn: 96344
2010-02-16 11:11:14 +00:00
Dan Gohman 521efe68ab Split the main for-each-use loop again, this time for GenerateTruncates,
as it also peeks at which registers are being used by other uses. This
makes LSR less sensitive to use-list order.

llvm-svn: 96308
2010-02-16 01:42:53 +00:00
Dan Gohman e4e51a63da Fix whitespace.
llvm-svn: 96179
2010-02-14 18:51:39 +00:00
Dan Gohman e7f74bb16c Fix a comment.
llvm-svn: 96178
2010-02-14 18:51:20 +00:00
Dan Gohman bb7d52213c When complicated expressions are broken down into subexpressions
with multiplication by constants distributed through, occasionally
those subexpressions can include both x and -x. For now, if this
condition is discovered within LSR, just prune such cases away,
as they won't be profitable. This fixes a "zero allocated in a
base register" assertion failure.

llvm-svn: 96177
2010-02-14 18:50:49 +00:00
Dan Gohman 2d0f96d49a Actually, this code doesn't have to be quite so conservative in
the no-TLI case. But it should still default to declining the
transformation.

llvm-svn: 96152
2010-02-14 03:21:49 +00:00
Dan Gohman cb76a806f0 Don't attempt aggressive post-inc uses if TargetLowering is not available,
because profitability can't be sufficiently approximated.

llvm-svn: 96148
2010-02-14 02:45:21 +00:00
John McCall 0daaf13b97 Make LSR not crash if invoked without target lowering info, e.g. if invoked
from opt.

llvm-svn: 96135
2010-02-13 23:40:16 +00:00
Dan Gohman 5b18f039eb Fix a pruning heuristic which implicitly assumed that SmallPtrSet is
deterministically sorted.

llvm-svn: 96071
2010-02-13 02:06:02 +00:00
Dan Gohman 2b75de97c0 Reapply 95979, a compile-time speedup, now that the bug it exposed is fixed.
llvm-svn: 96005
2010-02-12 19:35:25 +00:00
Dan Gohman 363f847ec6 Fix this code to avoid dereferencing an end() iterator in
offset distributions it doesn't expect.

llvm-svn: 96002
2010-02-12 19:20:37 +00:00
Daniel Dunbar e0b2c69d3c Revert "Reverse the order for collecting the parts of an addrec. The order", it
is breaking llvm-gcc bootstrap.

llvm-svn: 95988
2010-02-12 17:27:08 +00:00
Dan Gohman 0194f58047 Reverse the order for collecting the parts of an addrec. The order
doesn't matter, except that ScalarEvolution tends to need less time
to fold the results this way.

llvm-svn: 95979
2010-02-12 11:08:26 +00:00
Dan Gohman 45774ce0ad Reapply the new LoopStrengthReduction code, with compile time and
bug fixes, and with improved heuristics for analyzing foreign-loop
addrecs.

This change also flattens IVUsers, eliminating the stride-oriented
groupings, which makes it easier to work with.

llvm-svn: 95975
2010-02-12 10:34:29 +00:00
Bill Wendling 48816a0b3f Generic reformatting and comment fixing. No functionality change.
llvm-svn: 94771
2010-01-29 00:52:43 +00:00
Bill Wendling 8277838cf8 Add newline to debugging output, and fix some grammar-os in comment.
llvm-svn: 94765
2010-01-29 00:27:39 +00:00
Dan Gohman 045f81981a Revert LoopStrengthReduce.cpp to pre-r94061 for now.
llvm-svn: 94123
2010-01-22 00:46:49 +00:00
Dan Gohman b1ee154b6b When inserting expressions for post-increment users which contain
loop-variant components, adds must be inserted after the increment.
Keep track of the increment position for this case, and insert
these adds in the correct location.

llvm-svn: 94110
2010-01-21 23:01:22 +00:00
Dan Gohman cb8d577eb2 Include IVUsers information in LSR's debug output.
llvm-svn: 94108
2010-01-21 22:46:32 +00:00
Dan Gohman 29916e023d Prune the search for candidate formulae if the number of register
operands exceeds the number of registers used in the initial
solution, as that wouldn't lead to a profitable solution anyway.

llvm-svn: 94107
2010-01-21 22:42:49 +00:00
Dan Gohman c903499ff8 Add a comment.
llvm-svn: 94104
2010-01-21 21:31:09 +00:00
Dan Gohman 51ad99d2c5 Re-implement the main strength-reduction portion of LoopStrengthReduction.
This new version is much more aggressive about doing "full" reduction in
cases where it reduces register pressure, and also more aggressive about
rewriting induction variables to count down (or up) to zero when doing so
reduces register pressure.

It currently uses fairly simplistic algorithms for finding reuse
opportunities, but it introduces a new framework allows it to combine
multiple strategies at once to form hybrid solutions, instead of doing
all full-reduction or all base+index.

llvm-svn: 94061
2010-01-21 02:09:26 +00:00
Dan Gohman b5358003fb Set Changed properly after calling DeleteDeadPHIs.
llvm-svn: 92735
2010-01-05 16:31:45 +00:00
David Greene 2330f78075 Remove dump routine and the associated Debug.h from a header. Patch up
other files to compensate.

llvm-svn: 92075
2009-12-23 22:58:38 +00:00
Dan Gohman 18fa5686f6 Add Loop contains utility methods for testing whether a loop
contains another loop, or an instruction. The loop form is
substantially more efficient on large loops than the typical
code it replaces.

llvm-svn: 91654
2009-12-18 01:24:09 +00:00
Dan Gohman fd7231f1fe Minor code simplification.
llvm-svn: 91653
2009-12-18 01:20:44 +00:00
Dan Gohman b1924e8a0f Don't pass const pointers by reference.
llvm-svn: 91647
2009-12-18 00:38:08 +00:00
Dan Gohman 92c3696524 Reapply LoopStrengthReduce and IVUsers cleanups, excluding the part
of 91296 that caused trouble -- the Processed list needs to be
preserved for the livetime of the pass, as AddUsersIfInteresting
is called from other passes.

llvm-svn: 91641
2009-12-18 00:06:20 +00:00
Evan Cheng 090ac0865a Revert 91280-91283, 91286-91289, 91291, 91293, 91295-91296. It apparently introduced a non-deterministic behavior in the optimizer somewhere.
llvm-svn: 91598
2009-12-17 09:39:49 +00:00
Dan Gohman 265ce318b8 Delete an unused function.
llvm-svn: 91432
2009-12-15 16:30:09 +00:00
Dan Gohman fbeec7270c Fix a thinko; isNotAlreadyContainedIn had a built-in negative, so the
condition was inverted when the code was converted to contains().

llvm-svn: 91295
2009-12-14 17:31:01 +00:00
Dan Gohman 416d5b7361 Remove unnecessary #includes.
llvm-svn: 91293
2009-12-14 17:19:06 +00:00
Dan Gohman 163fb26927 Instead of having a ScalarEvolution pointer member in BasedUser, just pass
the ScalarEvolution pointer into the functions which need it.

llvm-svn: 91289
2009-12-14 17:12:51 +00:00
Dan Gohman 8dbd4e3d16 Don't bother cleaning up if there's nothing to clean up.
llvm-svn: 91288
2009-12-14 17:10:44 +00:00
Dan Gohman 88c7e61c5b Delete an unused variable.
llvm-svn: 91287
2009-12-14 17:08:09 +00:00
Dan Gohman 838f604543 LSR itself doesn't need LoopInfo.
llvm-svn: 91283
2009-12-14 17:02:34 +00:00
Dan Gohman 273e692952 LSR itself doesn't need DominatorTree.
llvm-svn: 91282
2009-12-14 16:57:08 +00:00
Dan Gohman c3513095cf Remove the code in LSR that manually hoists expansions out of loops;
SCEVExpander does this automatically.

llvm-svn: 91281
2009-12-14 16:52:55 +00:00
Dan Gohman ec2a7c58e8 Minor code cleanups.
llvm-svn: 91280
2009-12-14 16:37:29 +00:00
Jim Grosbach 6bf5305f5d grammar
llvm-svn: 89145
2009-11-17 21:37:04 +00:00
Jim Grosbach e4e018ae67 80-column violations
llvm-svn: 89123
2009-11-17 19:05:35 +00:00
Evan Cheng ba4e5da727 Generalize OptimizeLoopTermCond to optimize more loop terminating icmp to use postinc iv.
llvm-svn: 89116
2009-11-17 18:10:11 +00:00
Jim Grosbach 60f4854c76 Remove trailing whitespace
llvm-svn: 89110
2009-11-17 17:53:56 +00:00
Evan Cheng 85a9f430e9 - Teach LSR to avoid changing cmp iv stride if it will create an immediate that
cannot be folded into target cmp instruction.
- Avoid a phase ordering issue where early cmp optimization would prevent the
  later count-to-zero optimization.
- Add missing checks which could cause LSR to reuse stride that does not have
  users.
- Fix a bug in count-to-zero optimization code which failed to find the pre-inc
  iv's phi node.
- Remove, tighten, loosen some incorrect checks disable valid transformations.
- Quite a bit of code clean up.

llvm-svn: 86969
2009-11-12 07:35:05 +00:00
Evan Cheng 12f146d8f7 Block terminator may be a switch.
llvm-svn: 86761
2009-11-11 00:00:21 +00:00
Evan Cheng 87fe40b32d Generalize lsr code that optimize loop to count down towards zero.
llvm-svn: 86715
2009-11-10 21:14:05 +00:00
Dan Gohman a1bf0c0acc Teach LSR to avoid calling SplitCriticalEdge on edges with indirectbr.
llvm-svn: 86193
2009-11-05 23:34:59 +00:00
Dan Gohman a83ac2d9e7 Update various Loop optimization passes to cope with the possibility that
LoopSimplify form may not be available.

llvm-svn: 86175
2009-11-05 21:11:53 +00:00
Dan Gohman d632f89596 Make LSR's OptimizeShadowIV ignore induction variables with negative
strides for now, because it doesn't handle them correctly. This fixes a
miscompile of SingleSource/Benchmarks/Misc-C++/ray.

This problem was usually hidden because indvars transforms such induction
variables into negations of canonical induction variables.

llvm-svn: 85118
2009-10-26 15:32:57 +00:00
Nick Lewycky 54d7179a25 Remove ICmpInst::isSignedPredicate which was a reimplementation
CmpInst::isSigned.

llvm-svn: 85037
2009-10-25 05:20:17 +00:00
Nick Lewycky 42fb7452df Instruction::clone does not need to take an LLVMContext&. Remove that and
update all the callers.

llvm-svn: 82889
2009-09-27 07:38:41 +00:00
Dan Gohman 3ddbc242fb Re-apply r80926, with fixes: keep the domtree informed of new blocks
that get created during loop unswitching, and fix SplitBlockPredecessors'
LCSSA updating code to create new PHIs instead of trying to just move
existing ones.

Also, optimize Loop::verifyLoop, since it gets called a lot. Use
searches on a sorted list of blocks instead of calling the "contains"
function, as is done in other places in the Loop class, since "contains"
does a linear search. Also, don't call verifyLoop from LoopSimplify or
LCSSA, as the PassManager is already calling verifyLoop as part of
LoopInfo's verifyAnalysis.

llvm-svn: 81221
2009-09-08 15:45:00 +00:00
Evan Cheng 904199547b Revert r80926. It causes loop unswitch assertion and slow down some JIT tests significantly.
llvm-svn: 81101
2009-09-06 02:26:10 +00:00
Dan Gohman 4c1bdcf5d7 Add a verifyAnalysis to LoopInfo, LoopSimplify, and LCSSA form that verify
that these passes are properly preserved.

Fix several transformation passes that claimed to preserve LoopSimplify
form but weren't.

llvm-svn: 80926
2009-09-03 16:31:42 +00:00
Chris Lattner 2dd09dbdf7 eliminate VISIBILITY_HIDDEN from Transforms/Scalar. PR4861
llvm-svn: 80766
2009-09-02 06:11:42 +00:00
Chris Lattner b25de3ff60 eliminate the "Value" printing methods that print to a std::ostream.
This required converting a bunch of stuff off DOUT and other cleanups.

llvm-svn: 79819
2009-08-23 04:37:46 +00:00
Owen Anderson 55f1c09e31 Push LLVMContexts through the IntegerType APIs.
llvm-svn: 78948
2009-08-13 21:58:54 +00:00
Owen Anderson 53aa7a960c Rename MVT to EVT, in preparation for splitting SimpleValueType out into its own struct type.
llvm-svn: 78610
2009-08-10 22:56:29 +00:00
Dan Gohman 298bce2aa9 Check for !isa<Constant> instead of isa<Instruction>. This
matches what the comment says, and it avoids spurious BitCast
instructions for Argument values.

llvm-svn: 78121
2009-08-04 23:23:56 +00:00
Owen Anderson 5a1acd9912 Move a few more APIs back to 2.5 forms. The only remaining ones left to change back are
metadata related, which I'm waiting on to avoid conflicting with Devang.

llvm-svn: 77721
2009-07-31 20:28:14 +00:00
Douglas Gregor 47d02732e0 Eliminate a few unused-variable warnings
llvm-svn: 77519
2009-07-29 22:41:10 +00:00
Owen Anderson 4056ca9568 Move types back to the 2.5 API.
llvm-svn: 77516
2009-07-29 22:17:13 +00:00
Owen Anderson 487375e9a2 Move ConstantExpr to 2.5 API.
llvm-svn: 77494
2009-07-29 18:55:55 +00:00
Owen Anderson 69c464dec4 Move ConstantFP construction back to the 2.5-ish API.
llvm-svn: 77247
2009-07-27 20:59:43 +00:00
Daniel Dunbar 6115b39ffd Remove Value::getName{Start,End}, the last of the old Name APIs.
llvm-svn: 77152
2009-07-26 09:48:23 +00:00
Owen Anderson edb4a70325 Revert the ConstantInt constructors back to their 2.5 forms where possible, thanks to contexts-on-types. More to come.
llvm-svn: 77011
2009-07-24 23:12:02 +00:00
Owen Anderson 47db941fd3 Get rid of the Pass+Context magic.
llvm-svn: 76702
2009-07-22 00:24:57 +00:00
Dan Gohman cc85ae132c Make Loop and MachineLoop be subclasses of LoopBase, rather than typedefs,
using the Curiously Recurring Template Pattern with LoopBase.

This will help further refactoring, and future functionality for
Loop. Also, Headers can now foward-declare Loop, instead of pulling
in LoopInfo.h or doing tricks.

llvm-svn: 75519
2009-07-13 21:51:15 +00:00
Owen Anderson 1e5f00e7a7 This started as a small change, I swear. Unfortunately, lots of things call the [I|F]CmpInst constructors. Who knew!?
llvm-svn: 75200
2009-07-09 23:48:35 +00:00
Dan Gohman af75234955 Change all SCEV* to SCEV *.
llvm-svn: 74918
2009-07-07 17:06:11 +00:00
Owen Anderson 80baed63b4 Second batch of passes using LLVMContext.
llvm-svn: 74753
2009-07-03 00:54:20 +00:00
Dan Gohman f19aeec3f5 Extend ScalarEvolution's multiple-exit support to compute exact
trip counts in more cases.

Generalize ScalarEvolution's isLoopGuardedByCond code to recognize
And and Or conditions, splitting the code out into an
isNecessaryCond helper function so that it can evaluate Ands and Ors
recursively, and make SCEVExpander be much more aggressive about
hoisting instructions out of loops.

test/CodeGen/X86/pr3495.ll has an additional instruction now, but
it appears to be due to an arbitrary register allocation difference.

llvm-svn: 74048
2009-06-24 01:18:18 +00:00
Dan Gohman f522a4e034 Don't emit a redundant BitCastInst if the value to be defined in the
preheader is already an instruction.

llvm-svn: 74031
2009-06-24 00:28:59 +00:00
Owen Anderson 65b6056e37 SCEVHandle is no more!
llvm-svn: 73906
2009-06-22 21:39:50 +00:00
Dan Gohman 860379bcc2 Rename a variable for consistency with the ExitBlock vs ExitingBlock
terminology that LoopInfo uses.

llvm-svn: 73863
2009-06-21 23:48:38 +00:00
Dan Gohman 724f825f96 Fix a typo in a comment that Frits von Bommel noticed.
llvm-svn: 73796
2009-06-19 23:41:37 +00:00
Dan Gohman cc31110b95 Re-apply r73718, now that the fix in r73787 is in, and add a
hand-crafted testcase which demonstrates the bug that was exposed
in 254.gap.

llvm-svn: 73793
2009-06-19 23:23:27 +00:00
Dan Gohman 55e3dd9174 Fix LSR's OptimizeSMax to ignore max operators with more than 2 operands,
which it isn't prepared to handle.

llvm-svn: 73787
2009-06-19 23:03:46 +00:00
Evan Cheng 86076c9e30 Revert 73718. It's breaking 254.gap.
llvm-svn: 73783
2009-06-19 21:15:06 +00:00
Dan Gohman 8c9ac59455 Generalize LSR's OptimizeSMax to handle unsigned max tests as well
as signed max tests. Along with r73717, this helps CodeGen avoid
emitting code for a maximum operation for this class of loop.

llvm-svn: 73718
2009-06-18 20:23:18 +00:00
Dan Gohman a0348809b6 Remove the code from IVUsers that attempted to handle
casted induction variables in cases where the cast
isn't foldable. It ended up being a pessimization in
many cases. This could be fixed, but it would require
a bunch of complicated code in IVUsers' clients. The
advantages of this approach aren't visible enough to
justify it at this time.

llvm-svn: 73706
2009-06-18 16:54:06 +00:00
Dan Gohman d8329e8378 Update comments to use doxygen syntax.
llvm-svn: 73621
2009-06-17 17:51:33 +00:00
Dan Gohman 7ccc52f131 Support vector casts in more places, fixing a variety of assertion
failures.

To support this, add some utility functions to Type to help support
vector/scalar-independent code. Change ConstantInt::get and
ConstantFP::get to support vector types, and add an overload to
ConstantInt::get that uses a static IntegerType type, for
convenience.

Introduce a new getConstant method for ScalarEvolution, to simplify
common use cases.

llvm-svn: 73431
2009-06-15 22:12:54 +00:00
Dan Gohman 0652fd59ff Convert several parts of the ScalarEvolution framework to use
SmallVector instead of std::vector.

llvm-svn: 73357
2009-06-14 22:47:23 +00:00
Devang Patel 50fc5a3cd7 Simplify.
llvm-svn: 72965
2009-06-05 22:39:21 +00:00
Dan Gohman a5b9645c4b Split the Add, Sub, and Mul instruction opcodes into separate
integer and floating-point opcodes, introducing
FAdd, FSub, and FMul.

For now, the AsmParser, BitcodeReader, and IRBuilder all preserve
backwards compatability, and the Core LLVM APIs preserve backwards
compatibility for IR producers. Most front-ends won't need to change
immediately.

This implements the first step of the plan outlined here:
http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt

llvm-svn: 72897
2009-06-04 22:49:04 +00:00
Dan Gohman 4d1823680d Revert 72493 and replace it with a more conservative fix, for now: don't
rewrite the comparison if there is any implicit extension or truncation
on the induction variable. I'm planning for IVUsers to eventually take
over some of the work of this code, and for it to be generalized.

llvm-svn: 72496
2009-05-27 21:10:47 +00:00
Dan Gohman f4d85325c0 In ChangeCompareStride, when the stride to be reused is truncated to
a smaller type, promoted its offset back up to the type of the new
comparison. This fixes PR4222.

llvm-svn: 72493
2009-05-27 20:00:18 +00:00
Dan Gohman 7248923a5d Suppress the IV reversal transformation in the case that the RHS
of the comparison is defined inside the loop. This fixes a
use-before-def problem, because the transformation puts a use
of the RHS outside the loop.

llvm-svn: 72149
2009-05-20 00:34:08 +00:00
Dan Gohman 97f70add3c Add some more comments to the top of this file.
llvm-svn: 72131
2009-05-19 20:37:36 +00:00
Dan Gohman adc70d6806 Trim unneeded #includes.
llvm-svn: 72130
2009-05-19 20:35:26 +00:00
Dan Gohman 2649491f9c Teach SCEVExpander to expand arithmetic involving pointers into GEP
instructions. It attempts to create high-level multi-operand GEPs,
though in cases where this isn't possible it falls back to casting
the pointer to i8* and emitting a GEP with that. Using GEP instructions
instead of ptrtoint+arithmetic+inttoptr helps pointer analyses that
don't use ScalarEvolution, such as BasicAliasAnalysis.

Also, make the AddrModeMatcher more aggressive in handling GEPs.
Previously it assumed that operand 0 of a GEP would require a register
in almost all cases. It now does extra checking and can do more
matching if operand 0 of the GEP is foldable. This fixes a problem
that was exposed by SCEVExpander using GEPs.

llvm-svn: 72093
2009-05-19 02:15:55 +00:00
Dan Gohman 14d1339579 Rename UseTy to AccessTy, for consistency with getAccessType, and to
avoid ambiguity with the word "use" in IVStrideUse.

llvm-svn: 72012
2009-05-18 16:45:28 +00:00
Dale Johannesen 536de01bcf Add an int64_t variant of abs, for host environments
without one.  Use it where we were using abs on
int64_t objects.
(I strongly suspect the casts to unsigned in the
fragments in LoopStrengthReduce are not doing whatever
the original intent was, but the obvious change to
uint64_t doesn't work.  Maybe later.)

llvm-svn: 71612
2009-05-13 00:24:22 +00:00
Dan Gohman d76d71a291 Factor the code for collecting IV users out of LSR into an IVUsers class,
and generalize it so that it can be used by IndVarSimplify. Implement the
base IndVarSimplify transformation code using IVUsers. This removes
TestOrigIVForWrap and associated code, as ScalarEvolution now has enough
builtin overflow detection and folding logic to handle all the same cases,
and more. Run "opt -iv-users -analyze -disable-output" on your favorite
loop for an example of what IVUsers does.

This lets IndVarSimplify eliminate IV casts and compute trip counts in
more cases. Also, this happens to finally fix the remaining testcases
in PR1301.

Now that IndVarSimplify is being more aggressive, it occasionally runs
into the problem where ScalarEvolutionExpander's code for avoiding
duplicate expansions makes it difficult to ensure that all expanded
instructions dominate all the instructions that will use them. As a
temporary measure, IndVarSimplify now uses a FixUsesBeforeDefs function
to fix up instructions inserted by SCEVExpander. Fortunately, this code
is contained, and can be easily removed once a more comprehensive
solution is available.

llvm-svn: 71535
2009-05-12 02:17:14 +00:00
Evan Cheng 78a4eb844b Teach LSR to optimize more loop exit compares, i.e. change them to use postinc iv value. Previously LSR would only optimize those which are in the loop latch block. However, if LSR can prove it is safe (and profitable), it's now possible to change those not in the latch blocks to use postinc values.
Also, if the compare is the only use, LSR would place the iv increment instruction before the compare instead in the latch.

llvm-svn: 71485
2009-05-11 22:33:01 +00:00
Dale Johannesen 02cb2bf2e3 Reverse a loop that is counting up to a maximum to
count down to 0 instead, under very restricted
circumstances.  Adjust 4 testcases in which this
optimization fires.

llvm-svn: 71439
2009-05-11 17:15:42 +00:00
Evan Cheng b9dcc2c0c9 Factor out code that optimize loop terminating condition.
llvm-svn: 71305
2009-05-09 01:08:24 +00:00
Evan Cheng 342053cd27 Unbreak the build.
llvm-svn: 71091
2009-05-06 18:00:56 +00:00
David Greene 0dec5b9a75 Make sure to use signed arithmetic in APInt to fix a regression.
llvm-svn: 71090
2009-05-06 17:39:26 +00:00
Dan Gohman e58fc20f8d Fix a copy+pasto in a comment.
llvm-svn: 71035
2009-05-05 23:02:38 +00:00
Dan Gohman 96b18ccdd3 Delete a FIXME which is no longer relevant, and add a FIXME that is.
llvm-svn: 71033
2009-05-05 22:59:55 +00:00
Bill Wendling 5e2ac0cd9c Temporarily reverting r71008. It was causing this failure:
Running /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/
CodeGen/X86/dg.exp ...
FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/
CodeGen/X86/change-compare-stride-1.ll
Failed with exit(1) at line 2
while running: grep {cmpq       $-478,} change-compare-stride-1.ll.tmp
child process exited abnormally

llvm-svn: 71013
2009-05-05 20:49:46 +00:00
David Greene 246a3dfb10 Handle overflow of 64-bit loop conditions.
llvm-svn: 71008
2009-05-05 20:22:36 +00:00
Dan Gohman 48f8222293 Re-apply 70645, converting ScalarEvolution to use
CallbackVH, with fixes. allUsesReplacedWith need to
walk the def-use chains and invalidate all users of a
value that is replaced. SCEVs of users need to be
recalcualted even if the new value is equivalent. Also,
make forgetLoopPHIs walk def-use chains, since any
SCEV that depends on a PHI should be recalculated when
more information about that PHI becomes available.

llvm-svn: 70927
2009-05-04 22:30:44 +00:00
Dan Gohman a30370bc33 Constify a bunch of SCEV-using code.
llvm-svn: 70919
2009-05-04 22:02:23 +00:00
Dan Gohman 5036695c32 Revert r70645 for now; it's causing a variety of regressions.
llvm-svn: 70661
2009-05-03 05:46:20 +00:00
Dan Gohman e9a38d16fe Convert ScalarEvolution to use CallbackVH for its internal map. This
makes ScalarEvolution::deleteValueFromRecords, and it's code that
subtly needed to be called before ReplaceAllUsesWith, unnecessary.

It also makes ValueDeletionListener unnecessary.

llvm-svn: 70645
2009-05-02 21:19:20 +00:00
Dan Gohman ff08995589 Previously, RecursivelyDeleteDeadInstructions provided an option
of returning a list of pointers to Values that are deleted. This was
unsafe, because the pointers in the list are, by nature of what
RecursivelyDeleteDeadInstructions does, always dangling. Replace this
with a simple callback mechanism. This may eventually be removed if
all clients can reasonably be expected to use CallbackVH.

Use this to factor out the dead-phi-cycle-elimination code from LSR
utility function, and generalize it to use the
RecursivelyDeleteTriviallyDeadInstructions utility function.

This makes LSR more aggressive about eliminating dead PHI cycles;
adjust tests to either be less trivial or to simply expect fewer
instructions.

llvm-svn: 70636
2009-05-02 18:29:22 +00:00