Commit Graph

631 Commits

Author SHA1 Message Date
Andrew Trick a1c01ba8c7 Tighten up an internal LSR API that should check for NULL.
No test case, but should fix a scan_build warning.

llvm-svn: 177374
2013-03-19 04:14:57 +00:00
Jakub Staszak 11bd83551c Reduce indents in LSRInstance::NarrowSearchSpaceByCollapsingUnrolledCode method.
No functionality change.

llvm-svn: 175364
2013-02-16 16:08:15 +00:00
Andrew Trick bc7059032b LSR IVChain improvement.
Handle chains in which the same offset is used for both loads and
stores to the same array.

Fixes rdar://11410078.

llvm-svn: 174789
2013-02-09 01:11:01 +00:00
Jakub Staszak f23980aba5 Remove #includes from the commonly used LoopInfo.h.
llvm-svn: 174786
2013-02-09 01:04:28 +00:00
Preston Gurd 25c3b6acc0 This patch aims to improve compile time performance by increasing
the SCEV vector size in LoopStrengthReduce. It is observed that
the BaseRegs vector size is 4 in most cases,
and elements are frequently copied when it is initialized as
SmallVector<const SCEV *, 2> BaseRegs.
Our benchmark results show that the compilation time performance
improved by ~0.5%.

Patch by Wan Xiaofei.

llvm-svn: 174219
2013-02-01 20:41:27 +00:00
Chandler Carruth 7e31c8f0ae Fix an editor goof in r171738 that Bill spotted. He may even have a test
case, but looking at the diff this was an obviously unintended change.

Thanks for the careful review Bill! =]

llvm-svn: 172336
2013-01-12 23:46:04 +00:00
Chandler Carruth 6e479322aa Remove LSR's use of the random AddrMode struct. These variables were
already in a class, just inline the four of them. I suspect that this
class could be simplified some to not always keep distinct variables for
these things, but it wasn't clear to me how given the usage so I opted
for a trivial and mechanical translation.

This removes one of the two remaining users of a header in include/llvm
which does nothing more than define a 4 member struct.

llvm-svn: 171738
2013-01-07 15:04:40 +00:00
Chandler Carruth 26c59fa870 Switch the SCEV expander and LoopStrengthReduce to use
TargetTransformInfo rather than TargetLowering, removing one of the
primary instances of the layering violation of Transforms depending
directly on Target.

This is a really big deal because LSR used to be a "special" pass that
could only be tested fully using llc and by looking at the full output
of it. It also couldn't run with any other loop passes because it had to
be created by the backend. No longer is this true. LSR is now just
a normal pass and we should probably lift the creation of LSR out of
lib/CodeGen/Passes.cpp and into the PassManagerBuilder. =] I've not done
this, or updated all of the tests to use opt and a triple, because
I suspect someone more familiar with LSR would do a better job. This
change should be essentially without functional impact for normal
compilations, and only change behvaior of targetless compilations.

The conversion required changing all of the LSR code to refer to the TTI
interfaces, which fortunately are very similar to TargetLowering's
interfaces. However, it also allowed us to *always* expect to have some
implementation around. I've pushed that simplification through the pass,
and leveraged it to simplify code somewhat. It required some test
updates for one of two things: either we used to skip some checks
altogether but now we get the default "no" answer for them, or we used
to have no information about the target and now we do have some.

I've also started the process of removing AddrMode, as the TTI interface
doesn't use it any longer. In some cases this simplifies code, and in
others it adds some complexity, but I think it's not a bad tradeoff even
there. Subsequent patches will try to clean this up even further and use
other (more appropriate) abstractions.

Yet again, almost all of the formatting changes brought to you by
clang-format. =]

llvm-svn: 171735
2013-01-07 14:41:08 +00:00
Andrew Trick f950ce8e38 Fix a crash in LSR replaceCongruentIVs.
Indirect branch in the preheader crashes replaceCongruentIVs.
Fixes rdar://12910141.

llvm-svn: 171653
2013-01-06 05:59:39 +00:00
Chandler Carruth 9fb823bbd4 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

llvm-svn: 171366
2013-01-02 11:36:10 +00:00
Chandler Carruth ed0881b2a6 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

llvm-svn: 169131
2012-12-03 16:50:05 +00:00
Nadav Rotem 4dc976fbcb revert r166264 because the LTO build is still failing
llvm-svn: 166340
2012-10-19 21:28:43 +00:00
Nadav Rotem 4985ddc5e0 recommit the patch that makes LSR and LowerInvoke use the TargetTransform interface.
llvm-svn: 166264
2012-10-19 04:27:49 +00:00
Bob Wilson d6d9ccca38 Temporarily revert the TargetTransform changes.
The TargetTransform changes are breaking LTO bootstraps of clang.  I am
working with Nadav to figure out the problem, but I am reverting it for now
to get our buildbots working.

This reverts svn commits: 165665 165669 165670 165786 165787 165997
and I have also reverted clang svn 165741

llvm-svn: 166168
2012-10-18 05:43:52 +00:00
Nadav Rotem e10328737d Add a new interface to allow IR-level passes to access codegen-specific information.
llvm-svn: 165665
2012-10-10 22:04:55 +00:00
Nadav Rotem 35315fea70 Refactor the AddrMode class out of TLI to its own header file.
This class is used by LSR and a number of places in the codegen.
This is the first step in de-coupling LSR from TLI, and creating
a new interface in between them.

llvm-svn: 165455
2012-10-08 23:06:34 +00:00
Andrew Trick 402edbbe39 LSR critical edge splitting fix for PR13756.
llvm-svn: 164147
2012-09-18 17:51:33 +00:00
Manman Ren 49d684e1e2 Release build: guard dump functions with
"#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)"

No functional change. Update r163344.

llvm-svn: 163679
2012-09-12 05:06:18 +00:00
Manman Ren c3366ccecb Release build: guard dump functions with "ifndef NDEBUG"
No functional change.

llvm-svn: 163344
2012-09-06 19:55:56 +00:00
Richard Smith ad9c8e839e Don't bind a reference to a dereferenced null pointer (for return value of WeakVH::operator*).
llvm-svn: 162309
2012-08-21 20:35:14 +00:00
Andrew Trick c803706c18 Reapply r160340. LSR: Limit CollectSubexprs.
Speculatively fix crashes by code inspection. Can't reproduce them yet.

llvm-svn: 160344
2012-07-17 05:30:37 +00:00
Andrew Trick e834cb465a Revert "LSR: try not to blow up solving combinatorial problems brute force."
Some units tests crashed on a different platform.

llvm-svn: 160341
2012-07-17 05:05:21 +00:00
Andrew Trick 7cd6d426b3 LSR: try not to blow up solving combinatorial problems brute force.
This places limits on CollectSubexprs to constrains the number of
reassociation possibilities. It limits the recursion depth and skips
over chains of nested recurrences outside the current loop.

Fixes PR13361. Although underlying SCEV behavior is still potentially bad.

llvm-svn: 160340
2012-07-17 05:00:56 +00:00
Andrew Trick 653513b8dd LSR Fix: check SCEV expression safety before expansion.
All SCEV expressions used by LSR formulae must be safe to
expand. i.e. they may not contain UDiv unless we can prove nonzero
denominator.

Fixes PR11356: LSR hoists UDiv.

llvm-svn: 160205
2012-07-13 23:33:10 +00:00
Andrew Trick 8370c7c38f LSR: fix expansion of scaled reg in non-address type formulae.
For non-address users, Base and Scaled registers are not specially
associated to fit an address mode, so SCEVExpander should apply normal
expansion rules. Otherwise we may sink computation into inner loops
that have already been optimized.

llvm-svn: 158537
2012-06-15 20:07:29 +00:00
Andrew Trick aca8fb3c45 LSR fix: "Special" users are just like "Basic" users but allow -1 scale.
llvm-svn: 158536
2012-06-15 20:07:26 +00:00
Benjamin Kramer bde9176663 Fix typos found by http://github.com/lyda/misspell-check
llvm-svn: 157885
2012-06-02 10:20:22 +00:00
Rafael Espindola dd48931461 Make sure HoistInsertPosition finds a position that is dominated by all
inputs.

llvm-svn: 155809
2012-04-30 03:53:06 +00:00
Jakob Stoklund Olesen c90abc8956 Break up getProfitableChainIncrement().
The required checks are moved to ChainInstruction() itself and the
policy decisions are moved to IVChain::isProfitableInc().

Also cache the ExprBase in IVChain to avoid frequent recomputations.

No functional change intended.

llvm-svn: 155676
2012-04-26 23:33:11 +00:00
Jakob Stoklund Olesen a0337d7bd9 Turn IVChain into a struct.
No functional change intended.

llvm-svn: 155675
2012-04-26 23:33:09 +00:00
Jakob Stoklund Olesen 293673d788 Print IV chain numbers while collecting them.
llvm-svn: 155567
2012-04-25 18:01:32 +00:00
Andrew Trick 19f80c1e7e loop-reduce: Add an early bailout to catch extremely large loops.
This introduces a threshold of 200 IV Users, which is very
conservative but should be sufficient to avoid serious compile time
sink or stack overflow. The llvm test-suite with LTO never exceeds 190
users per loop.

The bug doesn't relate to a specific type of loop. Checking in an
arbitrary giant loop as a unit test would be silly.

Fixes rdar://11262507.

llvm-svn: 154983
2012-04-18 04:00:10 +00:00
Jakob Stoklund Olesen f2390e8303 Pass the right sign to TLI->isLegalICmpImmediate.
LSR can fold three addressing modes into its ICmpZero node:

  ICmpZero BaseReg + Offset      => ICmp BaseReg, -Offset
  ICmpZero -1*ScaleReg + Offset  => ICmp ScaleReg, Offset
  ICmpZero BaseReg + -1*ScaleReg => ICmp BaseReg, ScaleReg

The first two cases are only used if TLI->isLegalICmpImmediate() likes
the offset.

Make sure the right Offset sign is passed to this method in the second
case. The ARM version is not symmetric.

<rdar://problem/11184260>

llvm-svn: 154079
2012-04-05 03:10:56 +00:00
Andrew Trick 14779cc49e LSR ivchain bug fix: corner case with ConstantExpr.
Fixes PR11950.

llvm-svn: 153463
2012-03-26 20:28:37 +00:00
Andrew Trick 356a896394 comment typo
llvm-svn: 153462
2012-03-26 20:28:35 +00:00
Andrew Trick e51feea79c LSR cleanup: potential bug caught by PVS-Studio.
Thanks Andrey.

llvm-svn: 153451
2012-03-26 18:03:16 +00:00
Andrew Trick e3502cb204 Remove -enable-lsr-retry in time for 3.1.
llvm-svn: 153287
2012-03-22 22:42:51 +00:00
Andrew Trick d97b83e320 Remove -enable-lsr-nested in time for 3.1.
Tests cases have been removed but attached to open PR12330.

llvm-svn: 153286
2012-03-22 22:42:45 +00:00
Andrew Trick 070e540a3e LSR fix: Add isSimplifiedLoopNest to IVUsers analysis.
Only record IVUsers that are dominated by simplified loop
headers. Otherwise SCEVExpander will crash while looking for a
preheader.

I previously tried to work around this in LSR itself, but that was
insufficient. This way, LSR can continue to run if some uses are not
in simple loops, as long as we don't attempt to analyze those users.

Fixes <rdar://problem/11049788> Segmentation fault: 11 in LoopStrengthReduce

llvm-svn: 152892
2012-03-16 03:16:56 +00:00
David Blaikie 46a9f016c5 More dead code removal (using -Wunreachable-code)
llvm-svn: 148578
2012-01-20 21:51:11 +00:00
Andrew Trick b9c822ab0b Handle a corner case with IV chain collection with bailout instead of assert.
Fixes PR11783: bad cast to AddRecExpr.

llvm-svn: 148572
2012-01-20 21:23:40 +00:00
Andrew Trick c908b43d9f SCEVExpander fixes. Affects LSR and indvars.
LSR has gradually been improved to more aggressively reuse existing code, particularly existing phi cycles. This exposed problems with the SCEVExpander's sloppy treatment of its insertion point. I applied some rigor to the insertion point problem that will hopefully avoid an endless bug cycle in this area. Changes:

- Always used properlyDominates to check safe code hoisting.

- The insertion point provided to SCEV is now considered a lower bound. This is usually a block terminator or the use itself. Under no cirumstance may SCEVExpander insert below this point.

- LSR is reponsible for finding a "canonical" insertion point across expansion of different expressions.

- Robust logic to determine whether IV increments are in "expanded" form and/or can be safely hoisted above some insertion point.

Fixes PR11783: SCEVExpander assert.

llvm-svn: 148535
2012-01-20 07:41:13 +00:00
Andrew Trick 12728f04ca LSR fix: broaden the check for loop preheaders.
It's becoming clear that LoopSimplify needs to unconditionally create loop preheaders. But that is a bigger fix. For now, continuing to hack LSR.
Fixes rdar://10701050 "Cannot split an edge from an IndirectBrInst" assert.

llvm-svn: 148288
2012-01-17 06:45:52 +00:00
Andrew Trick d5d2db9af9 Enable LSR IV Chains with sufficient heuristics.
These heuristics are sufficient for enabling IV chains by
default. Performance analysis has been done for i386, x86_64, and
thumbv7. The optimization is rarely important, but can significantly
speed up certain cases by eliminating spill code within the
loop. Unrolled loops are prime candidates for IV chains. In many
cases, the final code could still be improved with more target
specific optimization following LSR. The goal of this feature is for
LSR to make the best choice of induction variables.

Instruction selection may not completely take advantage of this
feature yet. As a result, there could be cases of slight code size
increase.

Code size can be worse on x86 because it doesn't support postincrement
addressing. In fact, when chains are formed, you may see redundant
address plus stride addition in the addressing mode. GenerateIVChains
tries to compensate for the common cases.

On ARM, code size increase can be mitigated by using postincrement
addressing, but downstream codegen currently misses some opportunities.

llvm-svn: 147826
2012-01-10 01:45:08 +00:00
Andrew Trick 248d410e3e Adding IV chain generation to LSR.
After collecting chains, check if any should be materialized. If so,
hide the chained IV users from the LSR solver. LSR will only solve for
the head of the chain. GenerateIVChains will then materialize the
chained IV users by computing the IV relative to its previous value in
the chain.

In theory, chained IV users could be exposed to LSR's solver. This
would be considerably complicated to implement and I'm not aware of a
case where we need it. In practice it's more important to
intelligently prune the search space of nontrivial loops before
running the solver, otherwise the solver is often forced to prune the
most optimal solutions. Hiding the chained users does this well, so
that LSR is more likely to find the best IV for the chain as a whole.

llvm-svn: 147801
2012-01-09 21:18:52 +00:00
Andrew Trick 29fe5f03d7 Adding collection of IV chains to LSR.
This collects a set of IV uses within the loop whose values can be
computed relative to each other in a sequence. Following checkins will
make use of this information.

llvm-svn: 147797
2012-01-09 19:50:34 +00:00
Andrew Trick 4dc3eff5ae "Minor LSR debugging stuff"
llvm-svn: 147785
2012-01-09 18:58:16 +00:00
Andrew Trick 06f6c05d08 Enable redundant phi elimination after LSR.
This will be more important as we extend the LSR pass in ways that don't rely on the formula solver. In particular, we need it for constructing IV chains.

llvm-svn: 147724
2012-01-07 07:08:17 +00:00
Andrew Trick 732ad80dbb LSR: Don't optimize loops if an outer loop has no preheader.
LoopSimplify may not run on some outer loops, e.g. because of indirect
branches. SCEVExpander simply cannot handle outer loops with no preheaders.
Fixes rdar://10655343 SCEVExpander segfault.

llvm-svn: 147718
2012-01-07 03:16:50 +00:00
Andrew Trick 2ec61a896b LSR: run DeleteDeadPhis before replaceCongruentPhis.
llvm-svn: 147711
2012-01-07 01:36:44 +00:00
Andrew Trick 5adedf5d47 Extended replaceCongruentPhis to handle mixed phi types.
llvm-svn: 147707
2012-01-07 01:12:09 +00:00
Andrew Trick dc18e383b7 Cleanup. Clarify LSRInstance public methods.
llvm-svn: 146459
2011-12-13 00:55:33 +00:00
Andrew Trick e8b4f409b2 LSR: ignore strides in outer loops.
Since we're not rewriting IVs in other loops, there's not much reason
to consider their stride when generating formulae.
This should reduce the number of useless formulas considered by LSR.

llvm-svn: 146302
2011-12-10 00:25:00 +00:00
Andrew Trick 5df9096584 LSR: prune undesirable formulae early.
It's always good to prune early, but formulae that are unsatisfactory
in their own right need to be removed before running any other pruning
heuristics. We easily avoid generating such formulae, but we need them
as an intermediate basis for forming other good formulae.

llvm-svn: 145906
2011-12-06 03:13:31 +00:00
Benjamin Kramer 7ba71be392 Move code into anonymous namespaces.
llvm-svn: 145154
2011-11-26 23:01:57 +00:00
Nadav Rotem 51f71054b6 Fix MSVC warnings by adding a cast.
llvm-svn: 144721
2011-11-15 22:54:21 +00:00
Eli Friedman b46345d7c1 Avoid undefined behavior in negation in LSR. Patch by Ahmed Charles.
Someone more familiar with LSR should double-check that the extra cast is actually doing the right thing in the overflow cases; I'm not completely confident that's that case. 

llvm-svn: 141916
2011-10-13 23:48:33 +00:00
Andrew Trick ecbe22bb8d Add experimental -enable-lsr-phielim option.
I'm not sure we will need it in the long run, but the option is
currently useful for checking if the output of LSR is "clean".

llvm-svn: 141634
2011-10-11 02:30:45 +00:00
Andrew Trick 7fb669ab48 LSR should only reuse phis that match its formula.
Fixes rdar://problem/5064068

llvm-svn: 141442
2011-10-07 23:46:21 +00:00
Andrew Trick 8de329a9fc LSR should avoid redundant edge splitting.
This handles the case in which LSR rewrites an IV user that is a phi and
splits critical edges originating from a switch.
Fixes <rdar://problem/6453893> LSR is not splitting edges "nicely"

llvm-svn: 141059
2011-10-04 03:50:44 +00:00
Andrew Trick 168dfffdb8 typo + pasto
llvm-svn: 140769
2011-09-29 01:53:08 +00:00
Andrew Trick bc6de90a5f LSR: rewrite inner loops only.
Rewriting the entire loop nest now requires -enable-lsr-nested.
See PR11035 for some performance data.
A few unit tests specifically test nested LSR, and are now under a flag.

llvm-svn: 140762
2011-09-29 01:33:38 +00:00
Andrew Trick 581243919d Disable LSR retry by default.
Disabling aggressive LSR saves compilation time, and with the new
indvars behavior usually improves performance.

llvm-svn: 140590
2011-09-27 00:44:14 +00:00
Andrew Trick 8868faec63 LSR, one of the new Cost::isLoser() checks did not get merged in the previous checkin.
llvm-svn: 140583
2011-09-26 23:35:25 +00:00
Andrew Trick 784729d408 LSR cost metric minor fix and verification.
The minor bug heuristic was noticed by inspection. I added the
isLoser/isValid helpers because they will become more
important with subsequent checkins.

llvm-svn: 140580
2011-09-26 23:11:04 +00:00
Andrew Trick 8b2fe2f744 LSR minor bug fix in RateRegister.
No test case. Noticed by inspection and I doubt it ever affects the
outcome of the overall heuristic, let alone final codegen.

llvm-svn: 140431
2011-09-23 23:05:19 +00:00
Bill Wendling 3fb137f7ef LSR wants to split the landing pad's critical edge. Let it do it, but use the
proper function to do it.

llvm-svn: 138550
2011-08-25 05:55:40 +00:00
Bill Wendling 07efd6f1e0 When inserting new instructions, use getFirstInsertionPt instead of
getFirstNonPHI so that it will skip over the landingpad instructions as well.

llvm-svn: 138537
2011-08-25 01:08:34 +00:00
Bill Wendling 86c5cbe613 Skip the landingpad instruction when determining the insertion point.
llvm-svn: 138481
2011-08-24 21:06:46 +00:00
Andrew Trick bd243d0dfe LSR, correct fix for rdar://9786536. Silly casting bug.
llvm-svn: 135654
2011-07-21 01:45:54 +00:00
Andrew Trick 858e9f083d LSR must sometimes sign-extend before generating double constants.
rdar://9786536

llvm-svn: 135650
2011-07-21 01:05:01 +00:00
Andrew Trick 8acb434402 LSR crashes on an empty IVUsers list.
rdar://9786536

llvm-svn: 135644
2011-07-21 00:40:04 +00:00
Chris Lattner 229907cd11 land David Blaikie's patch to de-constify Type, with a few tweaks.
llvm-svn: 135375
2011-07-18 04:54:35 +00:00
Chris Lattner b1a1512119 start using the new helper methods a bit.
llvm-svn: 135251
2011-07-15 06:08:15 +00:00
Andrew Trick 411daa5e81 SCEVExpander: give new insts a name that identifies the reponsible pass.
llvm-svn: 133992
2011-06-28 05:07:32 +00:00
Andrew Trick fc4ccb20c6 IVUsers no longer needs to record the phis.
llvm-svn: 133518
2011-06-21 15:43:52 +00:00
Dan Gohman 6c4a319088 When checking for signed multiplication overflow, watch out for INT_MIN and -1.
This fixes PR9845.

llvm-svn: 131919
2011-05-23 21:07:39 +00:00
Andrew Trick f44aadf0fd indvars: Prototyping Sign/ZeroExtend elimination without canonical IVs.
No functionality enabled by default. Use -disable-iv-rewrite.
Extended IVUsers to keep track of the phi that represents the users' IV.
Added the WidenIV transform to replace a narrow IV with a wide IV
by doing a one-for-one replacement of IV users instead of expanding the
SCEV expressions. [sz]exts are removed and truncs are inserted.

llvm-svn: 131744
2011-05-20 18:25:42 +00:00
Dan Gohman 3268e4d692 When forming an ICmpZero LSRUse, normalize the non-IV operand
of the comparison, so that the resulting expression is fully
normalized. This fixes PR9939.

llvm-svn: 131576
2011-05-18 21:02:18 +00:00
Dan Gohman 6136e94897 Add an unfolded offset field to LSR's Formula record. This is used to
model constants which can be added to base registers via add-immediate
instructions which don't require an additional register to materialize
the immediate.

llvm-svn: 130743
2011-05-03 00:46:49 +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
Bill Wendling b902f1dd88 Reapply r129401 with patch for clang.
llvm-svn: 129419
2011-04-13 00:36:11 +00:00
Bill Wendling dbfde42468 Revert r129401 for now. Clang is using the old way of doing things.
llvm-svn: 129403
2011-04-12 22:59:27 +00:00
Bill Wendling 47c24875a1 Remove the unaligned load intrinsics in favor of using native unaligned loads.
Now that we have a first-class way to represent unaligned loads, the unaligned
load intrinsics are superfluous.

First part of <rdar://problem/8460511>.

llvm-svn: 129401
2011-04-12 22:46:31 +00:00
Jay Foad 52131344a2 Remove PHINode::reserveOperandSpace(). Instead, add a parameter to
PHINode::Create() giving the (known or expected) number of operands.

llvm-svn: 128537
2011-03-30 11:28:46 +00:00
Jay Foad e0938d8a87 (Almost) always call reserveOperandSpace() on newly created PHINodes.
llvm-svn: 128535
2011-03-30 11:19:20 +00:00
Andrew Trick 8b55b736b1 Added SCEV::NoWrapFlags to manage unsigned, signed, and self wrap
properties.
Added the self-wrap flag for SCEV::AddRecExpr.
A slew of temporary FIXMEs indicate the intention of the no-self-wrap flag
without changing behavior in this revision.

llvm-svn: 127590
2011-03-14 16:50:06 +00:00
Cameron Zwarich 97dae4d361 If we can't avoid running loop-simplify twice for now, at least avoid running
iv-users twice.

llvm-svn: 125318
2011-02-10 23:53:14 +00:00
Eric Christopher da6bd45088 Revert this in an attempt to bring the builders back.
llvm-svn: 125257
2011-02-10 01:48:24 +00:00
Cameron Zwarich 58c8670ab2 Turn this pass ordering:
Natural Loop Information
 Loop Pass Manager
   Canonicalize natural loops
 Scalar Evolution Analysis
 Loop Pass Manager
   Induction Variable Users
   Canonicalize natural loops
   Induction Variable Users
   Loop Strength Reduction

into this:

Scalar Evolution Analysis
Loop Pass Manager
  Canonicalize natural loops
  Induction Variable Users
  Loop Strength Reduction

This fixes <rdar://problem/8869639>. I also filed PR9184 on doing this sort of
thing automatically, but it seems easier to just change the ordering of the
passes if this is the only case.

llvm-svn: 125254
2011-02-10 01:07:54 +00:00
Dan Gohman de7f699754 Don't split any loop backedges, including backedges of loops other than
the active loop. This is generally desirable, and it avoids trouble
in situations such as the testcase in PR9123, though the failure
mode depends on use-list order, so it is infeasible to test.

llvm-svn: 125065
2011-02-08 00:55:13 +00:00
Cameron Zwarich b703654edc Remove code for updating dominance frontiers and some outdated references to
dominance and post-dominance frontiers.

llvm-svn: 123725
2011-01-18 04:11:31 +00:00
Chris Lattner bf0aa927cc split dom frontier handling stuff out to its own DominanceFrontier header,
so that Dominators.h is *just* domtree.  Also prune #includes a bit.

llvm-svn: 122714
2011-01-02 22:09:33 +00:00
Dan Gohman 20d9ce21ef Move SCEV::dominates and properlyDominates to ScalarEvolution.
llvm-svn: 119570
2010-11-17 21:41:58 +00:00
Dan Gohman afd6db9932 Move SCEV::isLoopInvariant and hasComputableLoopEvolution to be member
functions of ScalarEvolution, in preparation for memoization and
other optimizations.

llvm-svn: 119562
2010-11-17 21:23:15 +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
Dan Gohman 2fd85d7cd2 Filter out illegal formulae after updating offsets, not before, so that
formulae which become illegal as a result of the offset updating don't
escape.

This is for rdar://8529692. No testcase yet, because the given cases
hit use-list ordering differences.

llvm-svn: 116093
2010-10-08 19:33:26 +00:00
Dan Gohman 5947e1626a Delete the FormulaSorter class and inline its one method into its
one user. This code will be restructured soon and FormulaSorter
is getting in the way.

llvm-svn: 116012
2010-10-07 23:52:18 +00:00