Commit Graph

234 Commits

Author SHA1 Message Date
Peter Collingbourne
fcaf5fa89c Do not pass an invalid domtree to SimplifyInstruction from
LoopUnswitch.  Fixes PR12887.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157140 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-20 01:32:09 +00:00
Bill Wendling
bfbab99b58 Second attempt at PR12573:
Allow the "SplitCriticalEdge" function to split the edge to a landing pad. If
the pass is *sure* that it thinks it knows what it's doing, then it may go ahead
and specify that the landing pad can have its critical edge split. The loop
unswitch pass is one of these passes. It will split the critical edges of all
edges coming from a loop to a landing pad not within the loop. Doing so will
retain important loop analysis information, such as loop simplify.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155817 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-30 10:44:54 +00:00
Bill Wendling
6aa33274ed Remove hack from r154987. The problem persists even with it, so it's not even a good hack.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155813 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-30 09:23:48 +00:00
Bill Wendling
dc21604d4a Put this expensive check below the less expensive ones.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155166 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-19 23:31:07 +00:00
Bill Wendling
1356041296 Use a heavy hammer to fix PR12573.
If the loop contains invoke instructions, whose unwind edge escapes the loop,
then don't try to unswitch the loop. Doing so may cause the unwind edge to be
split, which not only is non-trivial but doesn't preserve loop simplify
information.

Fixes PR12573


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154987 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-18 06:00:09 +00:00
Andrew Trick
d9fc1ce809 Fix 12513: Loop unrolling breaks with indirect branches.
Take this opportunity to generalize the indirectbr bailout logic for
loop transformations. CFG transformations will never get indirectbr
right, and there's no point trying.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154386 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-10 05:14:42 +00:00
Andrew Trick
64c0748eb3 whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154385 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-10 05:14:37 +00:00
Stepan Dyatkovskiy
aad9c3f17a Fast fix for PR12343:
http://llvm.org/bugs/show_bug.cgi?id=12343

We have not trivial way for splitting edges that are goes from indirect branch. We can do it with some tricks, but it should be additionally discussed. And it is still dangerous due to difficulty of indirect branches controlling.

Fix forbids this case for unswitching.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153879 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-02 17:16:45 +00:00
Chandler Carruth
ae029098a5 This pass didn't want the inline cost per-se, it just wants generic code
metrics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152760 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-15 00:29:10 +00:00
Stepan Dyatkovskiy
3d3abe0852 llvm::SwitchInst
Renamed methods caseBegin, caseEnd and caseDefault with case_begin, case_end, and case_default.
Added some notes relative to case iterators.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152532 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-11 06:09:17 +00:00
Stepan Dyatkovskiy
c10fa6c801 Taken into account Duncan's comments for r149481 dated by 2nd Feb 2012:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20120130/136146.html

Implemented CaseIterator and it solves almost all described issues: we don't need to mix operand/case/successor indexing anymore. Base iterator class is implemented as a template since it may be initialized either from "const SwitchInst*" or from "SwitchInst*".

ConstCaseIt is just a read-only iterator.
CaseIt is read-write iterator; it allows to change case successor and case value.

Usage of iterator allows totally remove resolveXXXX methods. All indexing convertions done automatically inside the iterator's getters.

Main way of iterator usage looks like this:
SwitchInst *SI = ... // intialize it somehow

for (SwitchInst::CaseIt i = SI->caseBegin(), e = SI->caseEnd(); i != e; ++i) {
  BasicBlock *BB = i.getCaseSuccessor();
  ConstantInt *V = i.getCaseValue();
  // Do something.
}

If you want to convert case number to TerminatorInst successor index, just use getSuccessorIndex iterator's method.
If you want initialize iterator from TerminatorInst successor index, use CaseIt::fromSuccessorIndex(...) method.

There are also related changes in llvm-clients: klee and clang.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152297 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-08 07:06:20 +00:00
Stepan Dyatkovskiy
24473120a2 SwitchInst refactoring.
The purpose of refactoring is to hide operand roles from SwitchInst user (programmer). If you want to play with operands directly, probably you will need lower level methods than SwitchInst ones (TerminatorInst or may be User). After this patch we can reorganize SwitchInst operands and successors as we want.

What was done:

1. Changed semantics of index inside the getCaseValue method:
getCaseValue(0) means "get first case", not a condition. Use getCondition() if you want to resolve the condition. I propose don't mix SwitchInst case indexing with low level indexing (TI successors indexing, User's operands indexing), since it may be dangerous.
2. By the same reason findCaseValue(ConstantInt*) returns actual number of case value. 0 means first case, not default. If there is no case with given value, ErrorIndex will returned.
3. Added getCaseSuccessor method. I propose to avoid usage of TerminatorInst::getSuccessor if you want to resolve case successor BB. Use getCaseSuccessor instead, since internal SwitchInst organization of operands/successors is hidden and may be changed in any moment.
4. Added resolveSuccessorIndex and resolveCaseIndex. The main purpose of these methods is to see how case successors are really mapped in TerminatorInst.
4.1 "resolveSuccessorIndex" was created if you need to level down from SwitchInst to TerminatorInst. It returns TerminatorInst's successor index for given case successor.
4.2 "resolveCaseIndex" converts low level successors index to case index that curresponds to the given successor.

Note: There are also related compatability fix patches for dragonegg, klee, llvm-gcc-4.0, llvm-gcc-4.2, safecode, clang.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149481 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-01 07:49:51 +00:00
Stepan Dyatkovskiy
27bf56056b Fixed comment in loop-unswitch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148252 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-16 20:48:04 +00:00
Stepan Dyatkovskiy
0499c1fd8f Cosmetic patch for r148215.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148216 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-15 09:45:11 +00:00
Stepan Dyatkovskiy
209287d225 Fixup for r148132. Type replacement for LoopsProperties: from DenseMap to std::map, since we need to keep a valid pointer to properties of current loop.
Message for r148132:
LoopUnswitch: All helper data that is collected during loop-unswitch iterations was moved to separated class (LUAnalysisCache).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148215 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-15 09:44:07 +00:00
Eli Friedman
09a536a88b Speculatively revert r148132+r148133 to try and fix a buildbot failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148149 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-13 22:34:39 +00:00
Stepan Dyatkovskiy
5dab2bf293 Cosmetic patch for r148132.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148133 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-13 19:27:22 +00:00
Stepan Dyatkovskiy
a5a1e46d00 LoopUnswitch: All helper data that is collected during loop-unswitch iterations was moved to separated class (LUAnalysisCache).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148132 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-13 19:13:54 +00:00
Stepan Dyatkovskiy
88c5c42c5c Improved compile time:
1. Size heuristics changed. Now we calculate number of unswitching
branches only once per loop.
2. Some checks was moved from UnswitchIfProfitable to
processCurrentLoop, since it is not changed during processCurrentLoop
iteration. It allows decide to skip some loops at an early stage.
Extended statistics:
- Added total number of instructions analyzed.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147935 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-11 08:40:51 +00:00
Nick Lewycky
8a5641d856 Fix typo "infinte".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147226 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-23 23:49:25 +00:00
Chad Rosier
a816bf7c0d Add the actual code for r147175.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147176 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-22 21:10:46 +00:00
Chad Rosier
5ddb7a0105 Speculatively revert r146578 to determine if it is the cause of a number of
performance regressions (both execution-time and compile-time) on our
nightly testers.

Original commit message:
Fix for bug #11429: Wrong behaviour for switches. Small improvement for code
size heuristics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147131 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-22 02:40:57 +00:00
Stepan Dyatkovskiy
ac12ef4ad2 Fix for bug #11429: Wrong behaviour for switches. Small improvement for code size heuristics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146578 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-14 19:19:17 +00:00
Jakub Staszak
2fac1d5d61 SplitBlockPredecessors uses ArrayRef instead of Data and Size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146277 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-09 21:19:53 +00:00
Chad Rosier
618c1dbd29 Propagate TargetLibraryInfo throughout ConstantFolding.cpp and
InstructionSimplify.cpp.  Other fixups as needed.
Part of rdar://10500969

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145559 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-01 03:08:23 +00:00
Stepan Dyatkovskiy
be4c844648 Potential bug in RewriteLoopBodyWithConditionConstant: use iterator should not be changed inside the uses enumeration loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145432 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-29 20:34:39 +00:00
Benjamin Kramer
a9390a4d5f Stop emitting instructions with the name "tmp" they eat up memory and have to be uniqued, without any benefit.
If someone prefers %tmp42 to %42, run instnamer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140634 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-27 20:39:19 +00:00
Bill Wendling
d5520987d1 Split the landing pad basic block with the correct function. Also merge the
split landingpad instructions into a PHI node.
PR11016


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140592 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-27 00:59:31 +00:00
Jay Foad
95c3e48f95 Reinstate r133513 (reverted in r133700) with an additional fix for a
-Wshorten-64-to-32 warning in Instructions.h.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133708 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-23 09:09:15 +00:00
Eric Christopher
e59fbc04ad Revert r133513:
"Reinstate r133435 and r133449 (reverted in r133499) now that the clang
self-hosted build failure has been fixed (r133512)."

Due to some additional warnings.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133700 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-23 06:24:52 +00:00
Jay Foad
cd35e09a4a Reinstate r133435 and r133449 (reverted in r133499) now that the clang
self-hosted build failure has been fixed (r133512).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133513 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-21 10:33:19 +00:00
Chad Rosier
a88a0ca808 Revert r133435 and r133449 to appease buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133499 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-21 02:09:03 +00:00
Jay Foad
72f5f313d8 Change how PHINodes store their operands.
Change PHINodes to store simple pointers to their incoming basic blocks,
instead of full-blown Uses.

Note that this loses an optimization in SplitCriticalEdge(), because we
can no longer walk the use list of a BasicBlock to find phi nodes. See
the comment I removed starting "However, the foreach loop is slow for
blocks with lots of predecessors".

Extend replaceAllUsesWith() on a BasicBlock to also update any phi
nodes in the block's successors. This mimics what would have happened
when PHINodes were proper Users of their incoming blocks. (Note that
this only works if OldBB->replaceAllUsesWith(NewBB) is called when
OldBB still has a terminator instruction, so it still has some
successors.)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133435 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-20 14:38:01 +00:00
Nick Lewycky
444f297a78 Bail on unswitching a switch statement for a case with a critical edge. We name
which edge to split by pred/succ pair, which means that we can end up splitting
the wrong edge (by case value) in the switch statement entirely. Fixes PR10031!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132535 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-03 06:27:15 +00:00
Evan Cheng
237d10db8c Simplify r132022 based on Cameron's feedback.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132071 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-25 18:17:13 +00:00
Evan Cheng
21d378d735 Forgot dyn_cast check.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132025 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-24 23:47:50 +00:00
Evan Cheng
424641ef83 Fix LoopUnswitch bug. RewriteLoopBodyWithConditionConstant can delete a dead
case of a switch instruction. Back off this optimization when this would
eliminate all of the predecessors to the latch.

Sorry, I am unable to reduce a reasonably sized test case.

rdar://9486843


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132022 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-24 23:12:57 +00:00
Cameron Zwarich
71132af89a Make LoopUnswitch preserve ScalarEvolution by just forgetting everything about
a loop when unswitching it. It only does this in the complex case, because
everything should be fine already in the simple case.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125369 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-11 06:08:28 +00:00
Chris Lattner
b5fa5fcecc Revamp the ValueMapper interfaces in a couple ways:
1. Take a flags argument instead of a bool.  This makes
   it more clear to the reader what it is used for.
2. Add a flag that says that "remapping a value not in the
   map is ok".
3. Reimplement MapValue to share a bunch of code and be a lot
   more efficient.  For lookup failures, don't drop null values
   into the map.
4. Using the new flag a bunch of code can vaporize in LinkModules
   and LoopUnswitch, kill it.

No functionality change.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123058 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 08:15:20 +00:00
Duncan Sands
0f827639df Constant folding here is pointless, because InstructionSimplify
(which does constant folding and more) is called a few lines
later.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120042 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-23 20:24:21 +00:00
Duncan Sands
d0c6f3dafd Factor code for testing whether replacing one value with another
preserves LCSSA form out of ScalarEvolution and into the LoopInfo
class.  Use it to check that SimplifyInstruction simplifications
are not breaking LCSSA form.  Fixes PR8622.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119727 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-18 19:59:41 +00:00
Duncan Sands
eff0581583 If dom tree information is available, make it possible to pass
it to get better phi node simplification.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119055 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-14 18:36:10 +00:00
Owen Anderson
205942a4a5 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116854 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19 20:08:44 +00:00
Owen Anderson
081c34b725 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116820 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19 17:21:58 +00:00
Rafael Espindola
1ed219a9d2 Be more consistent in using ValueToValueMapTy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116387 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-13 01:36:30 +00:00
Owen Anderson
2ab36d3502 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116334 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-12 19:48:12 +00:00
Owen Anderson
ce665bd2e2 Now with fewer extraneous semicolons!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115996 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-07 22:25:06 +00:00
Dan Gohman
b0a57210a4 Fix loop unswitching's assumption that a code path which either
infinite loops or exits will eventually exit. This fixes PR5373.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112745 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01 21:46:45 +00:00
Chris Lattner
ea1092374c apparently unswitch had the same "Feature". Stop its
claims that it preserves domfrontier if it doesn't really.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112445 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-29 17:23:19 +00:00
Owen Anderson
90c579de5a Reapply r110396, with fixes to appease the Linux buildbot gods.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110460 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-06 18:33:48 +00:00