Commit Graph

255 Commits

Author SHA1 Message Date
Chandler Carruth
ac80dc7532 [PM/AA] Remove the Location typedef from the AliasAnalysis class now
that it is its own entity in the form of MemoryLocation, and update all
the callers.

This is an entirely mechanical change. References to "Location" within
AA subclases become "MemoryLocation", and elsewhere
"AliasAnalysis::Location" becomes "MemoryLocation". Hope that helps
out-of-tree folks update.

llvm-svn: 239885
2015-06-17 07:18:54 +00:00
Chandler Carruth
70c61c1a8a [PM/AA] Start refactoring AliasAnalysis to remove the analysis group and
port it to the new pass manager.

All this does is extract the inner "location" class used by AA into its
own full fledged type. This seems *much* cleaner as MemoryDependence and
soon MemorySSA also use this heavily, and it doesn't make much sense
being inside the AA infrastructure.

This will also make it much easier to break apart the AA infrastructure
into something that stands on its own rather than using the analysis
group design.

There are a few places where this makes APIs not make sense -- they were
taking an AliasAnalysis pointer just to build locations. I'll try to
clean those up in follow-up commits.

Differential Revision: http://reviews.llvm.org/D10228

llvm-svn: 239003
2015-06-04 02:03:15 +00:00
Benjamin Kramer
3a09ef64ee [CallSite] Make construction from Value* (or Instruction*) explicit.
CallSite roughly behaves as a common base CallInst and InvokeInst. Bring
the behavior closer to that model by making upcasts explicit. Downcasts
remain implicit and work as before.

Following dyn_cast as a mental model checking whether a Value *V isa
CallSite now looks like this: 
  if (auto CS = CallSite(V)) // think dyn_cast
instead of:
  if (CallSite CS = V)

This is an extra token but I think it is slightly clearer. Making the
ctor explicit has the advantage of not accidentally creating nullptr
CallSites, e.g. when you pass a Value * to a function taking a CallSite
argument.

llvm-svn: 234601
2015-04-10 14:50:08 +00:00
Benjamin Kramer
799003bf8c Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.
llvm-svn: 232998
2015-03-23 19:32:43 +00:00
Mehdi Amini
a28d91d81b DataLayout is mandatory, update the API to reflect it with references.
Summary:
Now that the DataLayout is a mandatory part of the module, let's start
cleaning the codebase. This patch is a first attempt at doing that.

This patch is not exactly NFC as for instance some places were passing
a nullptr instead of the DataLayout, possibly just because there was a
default value on the DataLayout argument to many functions in the API.
Even though it is not purely NFC, there is no change in the
validation.

I turned as many pointer to DataLayout to references, this helped
figuring out all the places where a nullptr could come up.

I had initially a local version of this patch broken into over 30
independant, commits but some later commit were cleaning the API and
touching part of the code modified in the previous commits, so it
seemed cleaner without the intermediate state.

Test Plan:

Reviewers: echristo

Subscribers: llvm-commits

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231740
2015-03-10 02:37:25 +00:00
Chandler Carruth
62d4215baa [PM] Move TargetLibraryInfo into the Analysis library.
While the term "Target" is in the name, it doesn't really have to do
with the LLVM Target library -- this isn't an abstraction which LLVM
targets generally need to implement or extend. It has much more to do
with modeling the various runtime libraries on different OSes and with
different runtime environments. The "target" in this sense is the more
general sense of a target of cross compilation.

This is in preparation for porting this analysis to the new pass
manager.

No functionality changed, and updates inbound for Clang and Polly.

llvm-svn: 226078
2015-01-15 02:16:27 +00:00
Hal Finkel
dd38c0b876 [DSE] Remove no-data-layout-only type-based overlap checking
DSE's overlap checking contained special logic, used only when no DataLayout
was available, which inferred a complete overwrite when the pointee types were
equal. This logic seems fine for regular loads/stores, but does not work for
memcpy and friends. Instead of fixing this, I'm just removing it.
Philosophically, transformations should not contain enhanced behavior used only
when data layout is lacking (data layout should be strictly additive), and
maintaining these rarely-tested code paths seems not worthwhile at this stage.

Credit to Aliaksei Zasenka for the bug report and the diagnosis. The test case
(slightly reduced from that provided by Aliaksei) replaces the original
contents of test/Transforms/DeadStoreElimination/no-targetdata.ll -- a few
other tests have been updated to have a data layout.

llvm-svn: 220035
2014-10-17 11:56:00 +00:00
Rui Ueyama
c487f7728e Revert "r214897 - Remove dead zero store to calloc initialized memory"
It broke msan.

llvm-svn: 214989
2014-08-06 19:30:38 +00:00
Philip Reames
00c9b6461f Remove dead zero store to calloc initialized memory
Optimize the following IR:

%1 = tail call noalias i8* @calloc(i64 1, i64 4)
%2 = bitcast i8* %1 to i32*
; This store is dead and should be removed
store i32 0, i32* %2, align 4

Memory returned by calloc is guaranteed to be zero initialized. If the value being stored is the constant zero (and the store is not otherwise observable across threads), we can delete the store.  If the store is to an out of bounds address, it is undefined and thus also removable.

Reviewed By: nicholas

Differential Revision: http://reviews.llvm.org/D3942

llvm-svn: 214897
2014-08-05 17:48:20 +00:00
Duncan P. N. Exon Smith
6c99015fe2 Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges."
This reverts commit r213474 (and r213475), which causes a miscompile on
a stage2 LTO build.  I'll reply on the list in a moment.

llvm-svn: 213562
2014-07-21 17:06:51 +00:00
Manuel Jacob
d11beffef4 [C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges.
Summary: This patch introduces two new iterator ranges and updates existing code to use it.  No functional change intended.

Test Plan: All tests (make check-all) still pass.

Reviewers: dblaikie

Reviewed By: dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4481

llvm-svn: 213474
2014-07-20 09:10:11 +00:00
Craig Topper
f40110f4d8 [C++] Use 'nullptr'. Transforms edition.
llvm-svn: 207196
2014-04-25 05:29:35 +00:00
Chandler Carruth
964daaaf19 [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE
definition below all of the header #include lines, lib/Transforms/...
edition.

This one is tricky for two reasons. We again have a couple of passes
that define something else before the includes as well. I've sunk their
name macros with the DEBUG_TYPE.

Also, InstCombine contains headers that need DEBUG_TYPE, so now those
headers #define and #undef DEBUG_TYPE around their code, leaving them
well formed modular headers. Fixing these headers was a large motivation
for all of these changes, as "leaky" macros of this form are hard on the
modules implementation.

llvm-svn: 206844
2014-04-22 02:55:47 +00:00
Craig Topper
3e4c697ca1 [C++11] Add 'override' keyword to virtual methods that override their base class.
llvm-svn: 202953
2014-03-05 09:10:37 +00:00
Benjamin Kramer
9c794c7a7c [C++11] Remove a leftover std::function instance.
It's not needed anymore.

llvm-svn: 202748
2014-03-03 19:49:02 +00:00
Chandler Carruth
d031fe9fcf [C++11] Remove the completely unnecessary requirement on SetVector's
remove_if that its predicate is adaptable. We don't actually need this,
we can write a generic adapter for any predicate.

This lets us remove some very wrong std::function usages. We should
never be using std::function for predicates to algorithms. This incurs
an *indirect* call overhead for every evaluation of the predicate, and
makes it very hard to inline through.

llvm-svn: 202742
2014-03-03 19:28:52 +00:00
Benjamin Kramer
b6d0bd48bd [C++11] Replace llvm::next and llvm::prior with std::next and std::prev.
Remove the old functions.

llvm-svn: 202636
2014-03-02 12:27:27 +00:00
Benjamin Kramer
3a377bce4e Now that we have C++11, turn simple functors into lambdas and remove a ton of boilerplate.
No intended functionality change.

llvm-svn: 202588
2014-03-01 11:47:00 +00:00
Rafael Espindola
6d6e87be9f Factor out calls to AA.getDataLayout().
llvm-svn: 202157
2014-02-25 15:52:19 +00:00
Rafael Espindola
5f57f462a8 Rename a few more DataLayout variables from TD to DL.
llvm-svn: 201870
2014-02-21 18:34:28 +00:00
Paul Robinson
af4e64d095 Disable most IR-level transform passes on functions marked 'optnone'.
Ideally only those transform passes that run at -O0 remain enabled,
in reality we get as close as we reasonably can.
Passes are responsible for disabling themselves, it's not the job of
the pass manager to do it for them.

llvm-svn: 200892
2014-02-06 00:07:05 +00:00
Reid Kleckner
26af2cae05 Update optimization passes to handle inalloca arguments
Summary:
I searched Transforms/ and Analysis/ for 'ByVal' and updated those call
sites to check for inalloca if appropriate.

I added tests for any change that would allow an optimization to fire on
inalloca.

Reviewers: nlewycky

Differential Revision: http://llvm-reviews.chandlerc.com/D2449

llvm-svn: 200281
2014-01-28 02:38:36 +00:00
Chandler Carruth
73523021d0 [PM] Split DominatorTree into a concrete analysis result object which
can be used by both the new pass manager and the old.

This removes it from any of the virtual mess of the pass interfaces and
lets it derive cleanly from the DominatorTreeBase<> template. In turn,
tons of boilerplate interface can be nuked and it turns into a very
straightforward extension of the base DominatorTree interface.

The old analysis pass is now a simple wrapper. The names and style of
this split should match the split between CallGraph and
CallGraphWrapperPass. All of the users of DominatorTree have been
updated to match using many of the same tricks as with CallGraph. The
goal is that the common type remains the resulting DominatorTree rather
than the pass. This will make subsequent work toward the new pass
manager significantly easier.

Also in numerous places things became cleaner because I switched from
re-running the pass (!!! mid way through some other passes run!!!) to
directly recomputing the domtree.

llvm-svn: 199104
2014-01-13 13:07:17 +00:00
Chandler Carruth
5ad5f15cff [cleanup] Move the Dominators.h and Verifier.h headers into the IR
directory. These passes are already defined in the IR library, and it
doesn't make any sense to have the headers in Analysis.

Long term, I think there is going to be a much better way to divide
these matters. The dominators code should be fully separated into the
abstract graph algorithm and have that put in Support where it becomes
obvious that evn Clang's CFGBlock's can use it. Then the verifier can
manually construct dominance information from the Support-driven
interface while the Analysis library can provide a pass which both
caches, reconstructs, and supports a nice update API.

But those are very long term, and so I don't want to leave the really
confusing structure until that day arrives.

llvm-svn: 199082
2014-01-13 09:26:24 +00:00
Dan Gohman
20a2ae9df5 Change GetPointerBaseWithConstantOffset's DataLayout argument from a
reference to a pointer, so that it can handle the case where DataLayout
is not available and behave conservatively.

llvm-svn: 174024
2013-01-31 02:00:45 +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
Benjamin Kramer
650b1dbd56 Unquadratize SetVector removal loops in DSE.
Erasing from the beginning or middle of the vector is expensive, remove_if can
do it in linear time even though it's a bit ugly without lambdas.

No functionality change.

llvm-svn: 165903
2012-10-14 10:21:31 +00:00
Micah Villmow
cdfe20b97f Move TargetData to DataLayout.
llvm-svn: 165402
2012-10-08 16:38:25 +00:00
Nick Lewycky
42bca056e0 Don't forget that strcpy and friends return a pointer to the destination, so
it's not a dead store if that pointer is used. Whoops!

llvm-svn: 164583
2012-09-25 01:55:59 +00:00
Nick Lewycky
627d217727 Remove unused name of variable to quiet a warning. Also canonicalize a
declaration to use the same form as in the rest of the file. No functionality
change.

llvm-svn: 164576
2012-09-24 23:47:23 +00:00
Nick Lewycky
9f4729d331 Teach DSE that strcpy, strncpy, strcat and strncat are all stores which may be
dead.

llvm-svn: 164561
2012-09-24 22:09:10 +00:00
Nick Lewycky
135ac9ac89 Move all the calls to AA.getTargetLibraryInfo() to using a TLI member variable.
No functionality change.

llvm-svn: 164560
2012-09-24 22:07:09 +00:00
Benjamin Kramer
2b11eb0729 DSE: Poking holes into a SetVector is expensive, avoid it if possible.
llvm-svn: 163480
2012-09-09 16:44:05 +00:00
Benjamin Kramer
8bcc971174 Make MemoryBuiltins aware of TargetLibraryInfo.
This disables malloc-specific optimization when -fno-builtin (or -ffreestanding)
is specified. This has been a problem for a long time but became more severe
with the recent memory builtin improvements.

Since the memory builtin functions are used everywhere, this required passing
TLI in many places. This means that functions that now have an optional TLI
argument, like RecursivelyDeleteTriviallyDeadFunctions, won't remove dead
mallocs anymore if the TLI argument is missing. I've updated most passes to do
the right thing.

Fixes PR13694 and probably others.

llvm-svn: 162841
2012-08-29 15:32:21 +00:00
Craig Topper
2a40418a99 Change greater than to greater than or equal so that an identical sized store to the same offset is treated as completing overwriting.
llvm-svn: 161857
2012-08-14 07:32:05 +00:00
Eli Friedman
08ec0a8122 isAllocLikeFn is allowed to return true for functions which read memory; make
sure we account for that correctly in DeadStoreElimination.  Fixes a regression
from r158919.  PR13547.

llvm-svn: 161468
2012-08-08 02:17:32 +00:00
Nadav Rotem
465834c85f Clean whitespaces.
llvm-svn: 160668
2012-07-24 10:51:42 +00:00
Nuno Lopes
55fff83422 refactor the MemoryBuiltin analysis:
- provide more extensive set of functions to detect library allocation functions (e.g., malloc, calloc, strdup, etc)
 - provide an API to compute the size and offset of an object pointed by

Move a few clients (GVN, AA, instcombine, ...) to the new API.
This implementation is a lot more aggressive than each of the custom implementations being replaced.

Patch reviewed by Nick Lewycky and Chandler Carruth, thanks.

llvm-svn: 158919
2012-06-21 15:45:28 +00:00
Evan Cheng
773b2cd63c It's not deterministic to iterate over SmallPtrSet. Replace it with SmallSetVector. Patch by Daniel Reynaud. rdar://11671029
llvm-svn: 158594
2012-06-16 04:28:11 +00:00
Dan Gohman
ed7c24e2d9 Teach DeadStoreElimination to eliminate exit-block stores with phi addresses.
llvm-svn: 156558
2012-05-10 18:57:38 +00:00
Nuno Lopes
300d629924 teach DSE and isInstructionTriviallyDead() about calloc
llvm-svn: 156553
2012-05-10 17:14:00 +00:00
Pete Cooper
39b5255df4 Reverted r152620 - DSE: Shorten memset when a later store overwrites the start of it. There were all sorts of buildbot issues
llvm-svn: 151621
2012-02-28 05:06:24 +00:00
Pete Cooper
f3862f91de DSE: Shorten memset when a later store overwrites the start of it
llvm-svn: 151620
2012-02-28 04:27:10 +00:00
Craig Topper
a2886c21d9 Convert assert(0) to llvm_unreachable
llvm-svn: 149967
2012-02-07 05:05:23 +00:00
Nick Lewycky
fe970725cc Fix infinite loop in DSE when deleting a free in a reachable loop that's also
trivially infinite.

llvm-svn: 146197
2011-12-08 22:36:35 +00:00
Pete Cooper
e03fe83d98 Fixed deadstoreelimination bug where negative indices were incorrectly causing the optimisation to occur
Turns out long long + unsigned long long is unsigned.  Doh!

Fixes http://llvm.org/bugs/show_bug.cgi?id=11455

llvm-svn: 145731
2011-12-03 00:04:30 +00:00
Nick Lewycky
c7f1e7993c Merge isObjectPointerWithTrustworthySize with getPointerSize. Use it when
looking at the size of the pointee. Fixes PR11390!

llvm-svn: 144773
2011-11-16 03:49:48 +00:00
Pete Cooper
a4237c380e Fixed bug in DeadStoreElimination commit r144239
Size of data being pointed to wasn't always being checked so some small writes were killing big writes

Fixes <rdar://problem/10426753>

llvm-svn: 144312
2011-11-10 20:22:08 +00:00
Pete Cooper
856977cb15 DeadStoreElimination can now trim the size of a store if the end of the store is dead.
Currently checks alignment and killing stores on a power of 2 boundary as this is likely
to trim the size of the earlier store without breaking large vector stores into scalar ones.

Fixes <rdar://problem/10140300>

llvm-svn: 144239
2011-11-09 23:07:35 +00:00
Nick Lewycky
f2905afe62 Do simple cross-block DSE when we encounter a free statement. Fixes PR11240.
llvm-svn: 143808
2011-11-05 10:48:42 +00:00
Daniel Dunbar
e6d40de414 Speculatively revert "DeadStoreElimination can now trim the size of a store if
the end of it is dead.", which appears to break bootstrapping LLVM.

llvm-svn: 143668
2011-11-04 00:48:26 +00:00
Pete Cooper
8a95aedb5d DeadStoreElimination can now trim the size of a store if the end of it is dead.
Only currently done if the later store is writing to a power of 2 address or 
has the same alignment as the earlier store as then its likely to not break up
large stores into smaller ones

Fixes <rdar://problem/10140300>

llvm-svn: 143630
2011-11-03 18:01:56 +00:00
Nick Lewycky
32f8051d66 A non-escaping malloc in the entry block is not unlike an alloca. Do dead-store
elimination on them too.

llvm-svn: 142735
2011-10-22 21:59:35 +00:00
Eli Friedman
c1702c8f22 Enhance the memdep interface so that users can tell the difference between a dependency which cannot be calculated and a path reaching the entry point of the function. This patch introduces isNonFuncLocal, which replaces isUnknown in some cases.
Patch by Xiaoyi Guo.

llvm-svn: 141896
2011-10-13 22:14:57 +00:00
Eli Friedman
72a93e5e9b Add comment to clarify the behavior of a helper in DSE.
llvm-svn: 139571
2011-09-13 01:28:59 +00:00
Owen Anderson
58704ee442 Try again at r138809 (make DSE more aggressive in removing dead stores at the end of a function), now with less deleting stores before memcpy's.
llvm-svn: 139150
2011-09-06 18:14:09 +00:00
Owen Anderson
e316e5b2ad Speculatively revert r138809 in an attempt to fix DragonEgg.
llvm-svn: 138829
2011-08-30 21:11:06 +00:00
Owen Anderson
d708ec4c6a When walking backwards to eliminate final stores to allocas at the end of a function, encountering an unrelated store should not cause us to give up like encountering a load does.
llvm-svn: 138809
2011-08-30 18:51:55 +00:00
Eli Friedman
9a468153e1 Atomic load/store handling for the passes using memdep (GVN, DSE, memcpyopt).
llvm-svn: 137888
2011-08-17 22:22:24 +00:00
Eli Friedman
89b694b096 Misc mid-level changes for new 'fence' instruction.
llvm-svn: 136205
2011-07-27 01:08:30 +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
Eli Friedman
7d58bc7bc0 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.
llvm-svn: 133031
2011-06-15 00:47:34 +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
5034159c5f * 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!

llvm-svn: 128577
2011-03-30 21:37:19 +00:00
Benjamin Kramer
e41395ac24 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.

llvm-svn: 128482
2011-03-29 20:28:57 +00:00
Bill Wendling
b5139920d6 Simplification noticed by Frits.
llvm-svn: 128333
2011-03-26 09:32:07 +00:00
Bill Wendling
19f33b9393 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.

llvm-svn: 128332
2011-03-26 08:02:59 +00:00
Bill Wendling
db40b5c899 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.

llvm-svn: 128319
2011-03-26 01:20:37 +00:00
Dan Gohman
0f124e1987 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.

llvm-svn: 124134
2011-01-24 18:53:32 +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
Dan Gohman
a4fcd2418d Move Value::getUnderlyingObject to be a standalone
function so that it can live in Analysis instead of
VMCore.

llvm-svn: 121885
2010-12-15 20:02:24 +00:00
Chris Lattner
4dc53e37d9 Use a stronger predicate here, pointed out by Duncan
llvm-svn: 121040
2010-12-06 21:48:10 +00:00
Chris Lattner
ca335e38cf add some DEBUG statements.
llvm-svn: 121038
2010-12-06 21:13:51 +00:00
Chris Lattner
94fbdf3814 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!

llvm-svn: 120974
2010-12-06 01:48:06 +00:00
Chris Lattner
903add84d9 Enhance DSE to handle the variable index case in PR8657.
llvm-svn: 120498
2010-11-30 23:43:23 +00:00
Chris Lattner
c0f3379ae0 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

llvm-svn: 120485
2010-11-30 23:05:20 +00:00
Chris Lattner
6712251f41 Make DeleteDeadInstruction be a static function, move some code around.
llvm-svn: 120471
2010-11-30 21:58:14 +00:00
Chris Lattner
51d67ce2ff 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.

llvm-svn: 120469
2010-11-30 21:47:58 +00:00
Chris Lattner
f80b39986f 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.

llvm-svn: 120467
2010-11-30 21:38:30 +00:00
Chris Lattner
7fe08b67fa 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.

llvm-svn: 120465
2010-11-30 21:32:12 +00:00
Chris Lattner
127818d746 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.

llvm-svn: 120463
2010-11-30 21:18:46 +00:00
Chris Lattner
60a8b3dab8 various cleanups and code simplification
llvm-svn: 120454
2010-11-30 19:48:15 +00:00
Chris Lattner
51c28a93cc make getPointerSize a static function. Add ivars to DSE for
AA and MD pass info instead of using getAnalysis<> all over.

llvm-svn: 120453
2010-11-30 19:34:42 +00:00
Chris Lattner
77d79fa25f reduce indentation, clean up TD use a bit.
llvm-svn: 120452
2010-11-30 19:28:23 +00:00
Chris Lattner
b63ba73b1b 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.

llvm-svn: 120445
2010-11-30 19:12:10 +00:00
Chris Lattner
58b779e9c2 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.

llvm-svn: 120406
2010-11-30 07:23:21 +00:00
Chris Lattner
3590ef817c rename a function and reduce some indentation, no functionality change.
llvm-svn: 120391
2010-11-30 05:30:45 +00:00
Chris Lattner
2227a8a192 rename doesClobberMemory -> hasMemoryWrite to be more specific, and
remove an actively-wrong comment.

llvm-svn: 120378
2010-11-30 01:37:52 +00:00
Chris Lattner
9d179d911d 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.

llvm-svn: 120377
2010-11-30 01:28:33 +00:00
Chris Lattner
9a146372b5 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.

llvm-svn: 120368
2010-11-30 00:28:45 +00:00
Chris Lattner
c3c754f750 my previous patch would cause us to start deleting some volatile
stores, fix and add a testcase.

llvm-svn: 120363
2010-11-30 00:12:39 +00:00
Chris Lattner
d4f1090948 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.

llvm-svn: 120359
2010-11-30 00:01:19 +00:00
Chris Lattner
2e8793482c fix PR8677, patch by Jakub Staszak!
llvm-svn: 120325
2010-11-29 21:59:31 +00:00
Chris Lattner
e48c31ce33 implement PR8576, deleting dead stores with intervening may-alias stores.
llvm-svn: 119927
2010-11-21 07:34:32 +00:00
Dan Gohman
d4b7fff2e8 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.

llvm-svn: 118875
2010-11-12 02:19:17 +00:00
Dan Gohman
f372cf869b Reapply r116831 and r116839, converting AliasAnalysis to use
uint64_t, plus fixes for places I missed before.

llvm-svn: 116875
2010-10-19 22:54:46 +00:00
Dan Gohman
b4aa503501 Revert r116831 and r116839, which are breaking selfhost builds.
llvm-svn: 116858
2010-10-19 21:06:16 +00:00
Dan Gohman
896ac62346 Oops, check in all the files for converting AliasAnalysis to
use uint64_t.

llvm-svn: 116839
2010-10-19 18:08:27 +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