Commit Graph

143 Commits

Author SHA1 Message Date
Eli Friedman
a990e071f2 Add "unknown" results for memdep, which mean "I don't know whether a dependence for the given instruction exists in the given block". This cleans up all the existing hacks in memdep which represent this concept by returning clobber with various unrelated instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133031 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-15 00:47:34 +00:00
Chris Lattner
7a2bdde0a0 Fix a ton of comment typos found by codespell. Patch by
Luis Felipe Strano Moraes!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129558 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-15 05:18:47 +00:00
Bill Wendling
31d244ead5 * The DSE code that tested for overlapping needed to take into account the fact
that one of the numbers is signed while the other is unsigned. This could lead
  to a wrong result when the signed was promoted to an unsigned int.

* Add the data layout line to the testcase so that it will test the appropriate
  thing.

Patch by David Terei!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128577 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-30 21:37:19 +00:00
Benjamin Kramer
ec3f227820 DSE: Remove an early exit optimization that depended on the ordering of a SmallPtrSet.
Fixes PR9569 and will hopefully make selfhost on ASLR-enabled systems more deterministic.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128482 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-29 20:28:57 +00:00
Bill Wendling
1a4d58af09 Simplification noticed by Frits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128333 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-26 09:32:07 +00:00
Bill Wendling
150c4a1a89 Rework the logic that determines if a store completely overlaps an ealier store.
There are two ways that a later store can comletely overlap a previous store:

1. They both start at the same offset, but the earlier store's size is <= the
   later's size, or
2. The earlier store's offset is > the later's offset, but it's offset + size
   doesn't extend past the later's offset + size.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128332 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-26 08:02:59 +00:00
Bill Wendling
e420449e80 PR9561: A store with a negative offset (via GEP) could erroniously say that it
completely overlaps a previous store, thus mistakenly deleting that store. Check
for this condition.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128319 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-26 01:20:37 +00:00
Dan Gohman
bd1801b555 Give GetUnderlyingObject a TargetData, to keep it in sync
with BasicAA's DecomposeGEPExpression, which recently began
using a TargetData. This fixes PR8968, though the testcase
is awkward to reduce.

Also, update several off GetUnderlyingObject's users
which happen to have a TargetData handy to pass it in.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124134 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-24 18:53:32 +00:00
Cameron Zwarich
301278719b Remove code for updating dominance frontiers and some outdated references to
dominance and post-dominance frontiers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123725 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-18 04:11:31 +00:00
Dan Gohman
5034dd318a Move Value::getUnderlyingObject to be a standalone
function so that it can live in Analysis instead of
VMCore.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121885 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15 20:02:24 +00:00
Chris Lattner
29d8d6b039 Use a stronger predicate here, pointed out by Duncan
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121040 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-06 21:48:10 +00:00
Chris Lattner
a9d4da85d6 add some DEBUG statements.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121038 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-06 21:13:51 +00:00
Chris Lattner
cc10244d77 Fix PR8728, a miscompilation I recently introduced. When optimizing
memcpy's like:
  memcpy(A, B)
  memcpy(A, C)

we cannot delete the first memcpy as dead if A and C might be aliases.
If so, we actually get:

  memcpy(A, B)
  memcpy(A, A)

which is not correct to transform into:

  memcpy(A, A)

This patch was heavily influenced by Jakub Staszak's patch in PR8728, thanks
Jakub!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120974 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-06 01:48:06 +00:00
Chris Lattner
3161ae1867 Enhance DSE to handle the variable index case in PR8657.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120498 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 23:43:23 +00:00
Chris Lattner
a04096580a teach DSE to use GetPointerBaseWithConstantOffset to analyze
may-aliasing stores that partially overlap with different base
pointers.  This implements PR6043 and the non-variable part of
PR8657


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120485 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 23:05:20 +00:00
Chris Lattner
7c80c15a8b Make DeleteDeadInstruction be a static function, move some code around.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120471 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 21:58:14 +00:00
Chris Lattner
d8d35316de switch RemoveAccessedObjects to use AliasAnalysis::Location to simplify
the code.  We now get accurate sizes on Loads, though it surely doesn't
matter in practice.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120469 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 21:47:58 +00:00
Chris Lattner
42cb684f8d two improvements to RemoveAccessedObjects:
1. if the underlying pointer passed in can be resolved
   to any argument or alloca, then we don't need to scan.
   Previously we would only avoid the scan if the alloca
   or byval was actually considered dead.
2. The dead store processing code is itself completely
   dead and didn't handle volatile stores right anyway,
   so delete it.  This allows simplifying the interface
   to RemoveAccessedObjects.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120467 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 21:38:30 +00:00
Chris Lattner
5fb0fb397c remove the "undead" terminology, which is nonstandard and never
made sense to me.  We now have a set of dead stack objects, and
they become live when loaded.  Fix a theoretical problem where
we'd pass in the wrong pointer to the alias query.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120465 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 21:32:12 +00:00
Chris Lattner
86dc6c08cf move call handling in handleEndBlock up a bit, and simplify it.
If the call might read all the allocas, stop scanning early.
Convert a vector to smallvector, shrink SmallPtrSet to 16 instead
of 64 to avoid crazy linear scans.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120463 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 21:18:46 +00:00
Chris Lattner
83d6759403 various cleanups and code simplification
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120454 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 19:48:15 +00:00
Chris Lattner
e3c611085e make getPointerSize a static function. Add ivars to DSE for
AA and MD pass info instead of using getAnalysis<> all over.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120453 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 19:34:42 +00:00
Chris Lattner
9801651193 reduce indentation, clean up TD use a bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120452 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 19:28:23 +00:00
Chris Lattner
55ee75d571 enhance isRemovable to refuse to delete volatile mem transfers
now that DSE hacks on them.  This fixes a regression I introduced,
by generalizing DSE to hack on transfers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120445 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 19:12:10 +00:00
Chris Lattner
cf82dc376a Rewrite the main DSE loop to be written in terms of reasoning
about pairs of AA::Location's instead of looking for MemDep's
"Def" predicate.  This is more powerful and general, handling
memset/memcpy/store all uniformly, and implementing PR8701 and
probably obsoleting parts of memcpyoptimizer.

This also fixes an obscure bug with init.trampoline and i8
stores, but I'm not surprised it hasn't been hit yet.  Enhancing
init.trampoline to carry the size that it stores would allow
DSE to be much more aggressive about optimizing them.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120406 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 07:23:21 +00:00
Chris Lattner
bbdc3703a3 rename a function and reduce some indentation, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120391 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 05:30:45 +00:00
Chris Lattner
72987a2742 rename doesClobberMemory -> hasMemoryWrite to be more specific, and
remove an actively-wrong comment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 01:37:52 +00:00
Chris Lattner
1ab4285b72 clean up handling of 'free', detangling it from everything else.
It can be seriously improved, but at least now it isn't intertwined
with the other logic.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120377 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 01:28:33 +00:00
Chris Lattner
201d1e56bb Teach basicaa that memset's modref set is at worst "mod" and never
contains "ref".

Enhance DSE to use a modref query instead of a store-specific hack
to generalize the "ignore may-alias stores" optimization to handle
memset and memcpy.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120368 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 00:28:45 +00:00
Chris Lattner
184d1ba738 my previous patch would cause us to start deleting some volatile
stores, fix and add a testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120363 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 00:12:39 +00:00
Chris Lattner
0f53f592ad two changes to DSE that shouldn't affect anything:
1. Don't bother trying to optimize:

lifetime.end(ptr)
store(ptr)

as it is undefined, and therefore shouldn't exist.

2. Move the 'storing a loaded pointer' xform up, simplifying
  the may-aliased store code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120359 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 00:01:19 +00:00
Chris Lattner
e9e973018a fix PR8677, patch by Jakub Staszak!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120325 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-29 21:59:31 +00:00
Chris Lattner
f6f1f062cc implement PR8576, deleting dead stores with intervening may-alias stores.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119927 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-21 07:34:32 +00:00
Dan Gohman
720a2ed6d9 Enhance DSE to handle the case where a free call makes more than
one store dead. This is especially noticeable in
SingleSource/Benchmarks/Shootout/objinst.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118875 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-12 02:19:17 +00:00
Dan Gohman
3da848bbda Reapply r116831 and r116839, converting AliasAnalysis to use
uint64_t, plus fixes for places I missed before.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116875 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19 22:54:46 +00:00
Dan Gohman
1db839e734 Revert r116831 and r116839, which are breaking selfhost builds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116858 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19 21:06:16 +00:00
Dan Gohman
9cb4c7f878 Oops, check in all the files for converting AliasAnalysis to
use uint64_t.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116839 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19 18:08:27 +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
Dan Gohman
f3a925dc7a Consistently use AliasAnalysis::UnknownSize instead of hardcoding ~0u.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116815 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19 17:06:23 +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
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
Owen Anderson
1f74590e9d Revert r110396 to fix buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110410 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-06 00:23:35 +00:00
Owen Anderson
9ccaf53ada 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110396 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-05 23:42:04 +00:00
Gabor Greif
d09475c226 use Value* constructor of CallSite to create potentially improper site, and test that
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109581 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-28 14:28:18 +00:00
Owen Anderson
d13db2c59c Fix batch of converting RegisterPass<> to INTIALIZE_PASS().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109045 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-21 22:09:45 +00:00
Dan Gohman
8c1ffae068 Don't claim to preserve AliasAnalysis. First, this is doesn't actually
have any effect, and second, deleting stores can potentially invalidate
an AliasAnalysis, and there's currently no notification for this.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107496 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-02 18:43:05 +00:00
Gabor Greif
7f1d7f5779 use ArgOperand API; tighten type of handleFreeWithNonTrivialDependency to be able to use isFreeCall whithout a cast or new overload
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106823 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-25 07:40:32 +00:00
Gabor Greif
3ccbb22eaf use ArgOperand API; introduce downcasted pointers into scope to facilitate this
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106734 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24 12:03:56 +00:00
Dan Gohman
fe60104ac9 Use pre-increment instead of post-increment when the result is not used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106542 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-22 15:08:57 +00:00