Commit Graph

371 Commits

Author SHA1 Message Date
Arnold Schwaighofer
8963071a14 BasicAA: We need to check both access sizes when comparing a gep and an
underlying object of unknown size.

Fixes PR18460.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199351 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-16 04:53:18 +00:00
Chandler Carruth
7f2eff792a [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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199104 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-13 13:07:17 +00:00
Chandler Carruth
56e1394c88 [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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199082 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-13 09:26:24 +00:00
Chandler Carruth
974a445bd9 Re-sort all of the includes with ./utils/sort_includes.py so that
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198685 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 11:48:04 +00:00
Arnold Schwaighofer
3036182e99 BasicAA: Use reachabilty instead of dominance for checking value equality in phi
cycles

This allows the value equality check to work even if we don't have a dominator
tree. Also add some more comments.

I was worried about compile time impacts and did not implement reachability but
used the dominance check in the initial patch. The trade-off was that the
dominator tree was required.
The llvm utility function isPotentiallyReachable cuts off the recursive search
after 32 visits. Testing did not show any compile time regressions showing my
worries unjustfied.

No compile time or performance regressions at O3 -flto -mavx on test-suite +
externals.

Addresses review comments from r198290.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198400 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-03 05:47:03 +00:00
Arnold Schwaighofer
1bdb320dae BasicAA: Fix value equality and phi cycles
When there are cycles in the value graph we have to be careful interpreting
"Value*" identity as "value" equivalence. We interpret the value of a phi node
as the value of its operands.
When we check for value equivalence now we make sure that the "Value*" dominates
all cycles (phis).

%0 = phi [%noaliasval, %addr2]
%l = load %ptr
%addr1 = gep @a, 0, %l
%addr2 = gep @a, 0, (%l + 1)
store %ptr ...

Before this patch we would return NoAlias for (%0, %addr1) which is wrong
because the value of the load is from different iterations of the loop.

Tested on x86_64 -mavx at O3 and O3 -flto with no performance or compile time
regressions.

PR18068
radar://15653794

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198290 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-02 03:31:36 +00:00
Matt Arsenault
74c996cbd1 Use correct size for address space in BasicAA.
The tests just hit this with a different sized
address space since I haven't figured out how
to use this to break it.

I thought I committed this a long time ago,
and I'm not sure why missing this hasn't caused
any problems.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194903 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-16 00:36:43 +00:00
Shuxin Yang
69bd41dfe3 Revert r193251 : Use address-taken to disambiguate global variable and indirect memops.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193489 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-27 03:08:44 +00:00
Shuxin Yang
8e3851a6eb Use address-taken to disambiguate global variable and indirect memops.
Major steps include:
 1). introduces a not-addr-taken bit-field in GlobalVariable
 2). GlobalOpt pass sets "not-address-taken" if it proves a global varirable 
    dosen't have its address taken.
 3). AA use this info for disambiguation. 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193251 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-23 17:28:19 +00:00
Matt Arsenault
b060a46b0d Use type helper functions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191574 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-27 22:18:51 +00:00
Jakub Staszak
394e5a9ee8 Remove trailing spaces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189173 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-24 14:16:00 +00:00
Craig Topper
a0ec3f9b7b Use SmallVectorImpl& instead of SmallVector to avoid repeating small vector size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186274 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 04:42:23 +00:00
Michael Kuperstein
9f5de6dadc Make BasicAliasAnalysis recognize the fact a noalias argument cannot alias another argument, even if the other argument is not itself marked noalias.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182755 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-28 08:17:48 +00:00
Nadav Rotem
8e4df489d0 Revert r176408 and r176407 to address PR15540.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179111 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-09 18:16:05 +00:00
Arnold Schwaighofer
742dbc1fc8 BasicAA: Only query twice if the result of the more general query was MayAlias
This is a compile time optimization. Before the patch we would do two traversals
on each call to aliasGEP - one with a set size parameter one with UnknownSize.
We can do better by first checking the result of the alias query with
UnknownSize.
Only if this one returns MayAlias do we query a second time using size and type.

This recovers an about 7% compile time regression on spec/ammp.

radar://12349960

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178045 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 18:07:53 +00:00
Nuno Lopes
2bc689c846 add getUnderlyingObjectSize()
this is similar to getObjectSize(), but doesnt subtract the offset
tweak the BasicAA code accordingly (per PR14988)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176407 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-02 11:23:34 +00:00
Shuxin Yang
d2eaf45af4 Fix a problem in alias analysis. It is about the misinterpretation of "Object".
This problem is exposed by r171325 which is already reverted. It is rather
hard to fabricate a testing case without it.

r171325 should *NOT* be resurrected as it has a potential problem although 
this problem dosen't directly contribute to PR14988.

The bug is tracked by:
  - rdar://13063553, and
  - http://llvm.org/bugs/show_bug.cgi?id=14988

Thank Arnold for coming up a better solution to this problem. After
comparing this solution and my original proposal, I decided to ditch mine.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176225 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-28 00:24:45 +00:00
Chandler Carruth
351ba145a7 Actually update the CMake and Makefile builds correctly, and update the
code that includes Intrinsics.gen directly.

This never showed up in my testing because the old Intrinsics.gen was
still kicking around in the make build system and was correct there. =[
Thankfully, some of the bots to clean rebuilds and that caught this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171373 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 12:09:16 +00:00
Chandler Carruth
0b8c9a80f2 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00
Arnold Schwaighofer
2b475922e6 Optimistically analyse Phi cycles
Analyse Phis under the starting assumption that they are NoAlias. Recursively
look at their inputs.
If they MayAlias/MustAlias there must be an input that makes them so.

Addresses bug 14351.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169788 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-10 23:02:41 +00:00
Chandler Carruth
d04a8d4b33 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. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169131 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 16:50:05 +00:00
Hal Finkel
c37f502d48 Phi speculation improvement for BasicAA
This is a partial solution to PR14351. It removes some of the special
significance of the first incoming phi value in the phi aliasing checking logic
in BasicAA. In the context of a loop, the old logic assumes that the first
incoming value is the interesting one (meaning that it is the one that comes
from outside the loop), but this is often not the case.  With this change, we
now test first the incoming value that comes from a block other than the parent
of the phi being tested.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168245 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-17 02:33:15 +00:00
Richard Osborne
544533301e Don't infer whether a value is captured in the current function from the
'nocapture' attribute.

The nocapture attribute only specifies that no copies are made that
outlive the function. This isn't the same as there being no copies at all.
This fixes PR14045.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167381 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-05 10:48:24 +00:00
Duncan Sands
a1beca6845 Apply the patch from PR14160. I failed to construct a testcase for this, but
I'm applying it anyway since it seems to be obviously correct.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167370 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-04 09:02:45 +00:00
Chandler Carruth
426c2bf5cd Revert the majority of the next patch in the address space series:
r165941: Resubmit the changes to llvm core to update the functions to
         support different pointer sizes on a per address space basis.

Despite this commit log, this change primarily changed stuff outside of
VMCore, and those changes do not carry any tests for correctness (or
even plausibility), and we have consistently found questionable or flat
out incorrect cases in these changes. Most of them are probably correct,
but we need to devise a system that makes it more clear when we have
handled the address space concerns correctly, and ideally each pass that
gets updated would receive an accompanying test case that exercises that
pass specificaly w.r.t. alternate address spaces.

However, from this commit, I have retained the new C API entry points.
Those were an orthogonal change that probably should have been split
apart, but they seem entirely good.

In several places the changes were very obvious cleanups with no actual
multiple address space code added; these I have not reverted when
I spotted them.

In a few other places there were merge conflicts due to a cleaner
solution being implemented later, often not using address spaces at all.
In those cases, I've preserved the new code which isn't address space
dependent.

This is part of my ongoing effort to clean out the partial address space
code which carries high risk and low test coverage, and not likely to be
finished before the 3.2 release looms closer. Duncan and I would both
like to see the above issues addressed before we return to these
changes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167222 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 09:14:31 +00:00
Micah Villmow
2c39b15073 Resubmit the changes to llvm core to update the functions to support different pointer sizes on a per address space basis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165941 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-15 16:24:29 +00:00
Micah Villmow
fb384d61c7 Revert 165732 for further review.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165747 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-11 21:27:41 +00:00
Micah Villmow
f3840d2c16 Add in the first iteration of support for llvm/clang/lldb to allow variable per address space pointer sizes to be optimized correctly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165726 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-11 17:21:41 +00:00
Micah Villmow
3574eca1b0 Move TargetData to DataLayout.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165402 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-08 16:38:25 +00:00
Duncan Sands
7c894691ef GCC doesn't understand that OrigAliasResult having a value is correlated with
ArePhisAssumedNoAlias, and warns that OrigAliasResult may be used uninitialized.
Pacify GCC.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164229 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-19 15:43:44 +00:00
Arnold Schwaighofer
3d5f96ee1b BasicAA: Recognize cyclic NoAlias phis
Enhances basic alias analysis to recognize phis whose first incoming values are
NoAlias and whose other incoming values are just the phi node itself through
some amount of recursion.

Example: With this change basicaa reports that ptr_phi and ptr_phi2 do not alias
each other.

bb:
 ptr = ptr2 + 1

loop:
  ptr_phi = phi [bb, ptr], [loop, ptr_plus_one]
  ptr2_phi = phi [bb, ptr2], [loop, ptr2_plus_one]
  ...
  ptr_plus_one = gep ptr_phi, 1
  ptr2_plus_one = gep ptr2_phi, 1

This enables the elimination of one load in code like the following:

extern int foo;

int test_noalias(int *ptr, int num, int* coeff) {
  int *ptr2 = ptr;
  int result = (*ptr++) * (*coeff--);
  while (num--) {
    *ptr2++ = *ptr;
    result +=  (*coeff--) * (*ptr++);
  }
  *ptr = foo;
  return result;
}

Part 2/2 of fix for PR13564.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163319 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-06 14:41:53 +00:00
Arnold Schwaighofer
029032693f BasicAA: GEPs of NoAlias'ing base ptr with equivalent indices are NoAlias
If we can show that the base pointers of two GEPs don't alias each other using
precise analysis and the indices and base offset are equal then the two GEPs
also don't alias each other.
This is primarily needed for the follow up patch that analyses NoAlias'ing PHI
nodes.

Part 1/2 of fix for PR13564.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163317 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-06 14:31:51 +00:00
Benjamin Kramer
998d3cca29 Switch BasicAliasAnalysis' cache to SmallDenseMap.
It relies on clear() being fast and the cache rarely has more than 1 or 2
elements, so give it an inline capacity and always shrink it back down in case
it grows. DenseMap will grow to 64 buckets which makes clear() a lot slower.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163215 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-05 16:49:37 +00:00
Benjamin Kramer
8e0d1c03ca 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162841 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-29 15:32:21 +00:00
Nuno Lopes
9e72a79ef4 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158919 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-21 15:45:28 +00:00
Eli Friedman
cd38485b8a Duncan pointed out that if the alignment isn't explicitly specified, it defaults to the ABI alignment. Given that, make this code a bit more aggressive in such cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151584 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-27 23:16:46 +00:00
Eli Friedman
1680a24e53 Teach BasicAA about the LLVM IR rules that allow reading past the end of an object given sufficient alignment. Fixes PR12098.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151553 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-27 20:46:07 +00:00
Nick Lewycky
55f4ab84e5 Move isKnownNonNull from private implementation detail of BasicAA to a public
function that others can use, next to llvm::isIdentifiedObject.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151446 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-25 10:56:28 +00:00
Dan Gohman
ebad58dc58 Remove a comment about an alternative approach that wouldn't
actually work, at least as described. LLVM Metadata is not
intended to suppress LLVM IR rules, as it can be stripped at
any time.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150821 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-17 18:33:38 +00:00
Nick Lewycky
173862e546 Refactor code to use new attribute getters on CallSite for NoCapture and ByVal.
Suggested in code review by Eli.

That code in InstCombine looks kinda suspicious.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145013 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-20 19:09:04 +00:00
Eli Friedman
8540101252 Remove the old atomic instrinsics. autoupgrade functionality is included with this patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141333 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-06 23:20:49 +00:00
Eli Friedman
e6fadced87 PR10628: Fix getModRefInfo so it queries the underlying alias() implementation correctly while checking nocapture calls.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140666 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-28 00:34:27 +00:00
Eli Friedman
184166da61 A couple minor corrections to r139276.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139277 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-08 02:37:07 +00:00
Eli Friedman
81ac8ddc67 Fix the logic in BasicAliasAnalysis::aliasGEP for comparing GEP's with variable differences so that it actually does something sane. Fixes PR10881.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139276 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-08 02:23:31 +00:00
Owen Anderson
e421ad64ff memset_pattern16 uses a 16 BYTE pattern, not a 16 BIT pattern. Add comments to that effect.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139205 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-06 23:43:26 +00:00
Owen Anderson
69acc93b3d Teach BasicAA about the aliasing properties of memset_pattern16.
Fixes PR10872 and <rdar://problem/10065079>.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139204 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-06 23:33:25 +00:00
Jeffrey Yasskin
a44defeb22 Explicitly cast narrowing conversions inside {}s that will become errors in
C++0x.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136211 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-27 06:22:51 +00:00
Chris Lattner
db125cfaf5 land David Blaikie's patch to de-constify Type, with a few tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135375 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-18 04:54:35 +00:00
Dan Gohman
9a09ca348f Initialize BasicAA's AliasCache to set it to use fewer buckets by
default, since it usually has very few elements. This speeds up
alias queries in many cases, because AliasCache.clear() doesn't
have to visit as many buckets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132862 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-10 22:30:30 +00:00
Dan Gohman
5f1312c36e Reapply r131781, now that the GVN bug with partially-aliasing loads
is disabled.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132632 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-04 06:50:18 +00:00