Commit Graph

3886 Commits

Author SHA1 Message Date
Dan Gohman 18fa5686f6 Add Loop contains utility methods for testing whether a loop
contains another loop, or an instruction. The loop form is
substantially more efficient on large loops than the typical
code it replaces.

llvm-svn: 91654
2009-12-18 01:24:09 +00:00
Dan Gohman fd7231f1fe Minor code simplification.
llvm-svn: 91653
2009-12-18 01:20:44 +00:00
Dan Gohman b1924e8a0f Don't pass const pointers by reference.
llvm-svn: 91647
2009-12-18 00:38:08 +00:00
Dan Gohman 92c3696524 Reapply LoopStrengthReduce and IVUsers cleanups, excluding the part
of 91296 that caused trouble -- the Processed list needs to be
preserved for the livetime of the pass, as AddUsersIfInteresting
is called from other passes.

llvm-svn: 91641
2009-12-18 00:06:20 +00:00
Eli Friedman 250b119d98 Allow instcombine to combine "sext(a) >u const" to "a >u trunc(const)".
llvm-svn: 91631
2009-12-17 22:42:29 +00:00
Eli Friedman 7cc86b4cc6 Make the ptrtoint comparison simplification work if one side is a global.
llvm-svn: 91624
2009-12-17 21:27:47 +00:00
Eli Friedman 5842c9968a Slightly generalize transformation of memmove(a,a,n) so that it also applies
to memcpy. (Such a memcpy is technically illegal, but in practice is safe
and is generated by struct self-assignment in C code.)

llvm-svn: 91621
2009-12-17 21:07:31 +00:00
Bob Wilson f3927b7994 Re-revert 91459. It's breaking the x86_64 darwin bootstrap.
llvm-svn: 91607
2009-12-17 18:34:24 +00:00
Evan Cheng 090ac0865a Revert 91280-91283, 91286-91289, 91291, 91293, 91295-91296. It apparently introduced a non-deterministic behavior in the optimizer somewhere.
llvm-svn: 91598
2009-12-17 09:39:49 +00:00
Daniel Dunbar ab42d42390 Reapply r91459, it was only unmasking the bug, and since TOT is still broken having it reverted does no good.
llvm-svn: 91559
2009-12-16 20:09:53 +00:00
Daniel Dunbar 133efc317e Revert "Reapply 91184 with fixes and an addition to the testcase to cover the
problem", this broke llvm-gcc bootstrap for release builds on
x86_64-apple-darwin10.

This reverts commit db22309800b224a9f5f51baf76071d7a93ce59c9.

llvm-svn: 91534
2009-12-16 10:56:17 +00:00
Chris Lattner f278addbdc reapply my strstr optimization. I have reproduced the x86-64 bootstrap
miscompile (i386.o miscompares) but it happens both with and without
this patch.

llvm-svn: 91532
2009-12-16 09:32:05 +00:00
Chris Lattner 177be32334 revert my strstr optimization, I'm told it breaks x86-64 bootstrap.
Will reapply with a fix when I get a chance.

llvm-svn: 91486
2009-12-16 00:46:02 +00:00
Bob Wilson e44756d7c2 Reapply 91184 with fixes and an addition to the testcase to cover the problem
found last time.  Instead of trying to modify the IR while iterating over it,
I've change it to keep a list of WeakVH references to dead instructions, and
then delete those instructions later.  I also added some special case code to
detect and handle the situation when both operands of a memcpy intrinsic are
referencing the same alloca.

llvm-svn: 91459
2009-12-15 22:00:51 +00:00
Chris Lattner 26ab363361 optimize strstr, PR5783
llvm-svn: 91438
2009-12-15 19:14:40 +00:00
Dan Gohman 265ce318b8 Delete an unused function.
llvm-svn: 91432
2009-12-15 16:30:09 +00:00
Chris Lattner 24aba42d04 add some other xforms that should be done as part of PR5783
llvm-svn: 91428
2009-12-15 09:05:13 +00:00
Chris Lattner 45d040bd85 Remove isPod() from DenseMapInfo, splitting it out to its own
isPodLike type trait.  This is a generally useful type trait for
more than just DenseMap, and we really care about whether something
acts like a pod, not whether it really is a pod.

llvm-svn: 91421
2009-12-15 07:26:43 +00:00
Dan Gohman fbeec7270c Fix a thinko; isNotAlreadyContainedIn had a built-in negative, so the
condition was inverted when the code was converted to contains().

llvm-svn: 91295
2009-12-14 17:31:01 +00:00
Dan Gohman 416d5b7361 Remove unnecessary #includes.
llvm-svn: 91293
2009-12-14 17:19:06 +00:00
Dan Gohman 163fb26927 Instead of having a ScalarEvolution pointer member in BasedUser, just pass
the ScalarEvolution pointer into the functions which need it.

llvm-svn: 91289
2009-12-14 17:12:51 +00:00
Dan Gohman 8dbd4e3d16 Don't bother cleaning up if there's nothing to clean up.
llvm-svn: 91288
2009-12-14 17:10:44 +00:00
Dan Gohman 88c7e61c5b Delete an unused variable.
llvm-svn: 91287
2009-12-14 17:08:09 +00:00
Dan Gohman 838f604543 LSR itself doesn't need LoopInfo.
llvm-svn: 91283
2009-12-14 17:02:34 +00:00
Dan Gohman 273e692952 LSR itself doesn't need DominatorTree.
llvm-svn: 91282
2009-12-14 16:57:08 +00:00
Dan Gohman c3513095cf Remove the code in LSR that manually hoists expansions out of loops;
SCEVExpander does this automatically.

llvm-svn: 91281
2009-12-14 16:52:55 +00:00
Dan Gohman ec2a7c58e8 Minor code cleanups.
llvm-svn: 91280
2009-12-14 16:37:29 +00:00
Chris Lattner aaa6ac10a6 revert r91184, because it causes a crash on a .bc file I just
sent to Bob.

llvm-svn: 91268
2009-12-14 05:11:02 +00:00
Bob Wilson 895f364ae6 Revise scalar replacement to be more flexible about handle bitcasts and GEPs.
While scanning through the uses of an alloca, keep track of the current offset
relative to the start of the alloca, and check memory references to see if
the offset & size correspond to a component within the alloca.  This has the
nice benefit of unifying much of the code from isSafeUseOfAllocation,
isSafeElementUse, and isSafeUseOfBitCastedAllocation.  The code to rewrite
the uses of a promoted alloca, after it is determined to be safe, is
reorganized in the same way.

Also, when rewriting GEP instructions, mark them as "in-bounds" since all the
indices are known to be safe.

llvm-svn: 91184
2009-12-11 23:47:40 +00:00
Eric Christopher 22889c049d Make sure the immediate dominator isn't NULL through iterations
of the loop. We could get to this condition via indirect
branches.

llvm-svn: 91009
2009-12-10 00:25:41 +00:00
Chris Lattner 9ccc879006 Fix PR5744, a case where we were getting the pointer size instead of the
value size.  This only manifested when memdep inprecisely returns clobber,
which is do to a caching issue in the PR5744 testcase.  We can 'efficiently
emulate' this by using '-no-aa'

llvm-svn: 91004
2009-12-10 00:11:45 +00:00
Chris Lattner 3ddf804f78 allow this to build when the #if 0's are enabled. No functionality change.
llvm-svn: 90999
2009-12-10 00:04:46 +00:00
Dan Gohman 72c367fb52 Dereference loopHeader after checking for null rather than before.
llvm-svn: 90990
2009-12-09 22:55:01 +00:00
Chris Lattner ca5f9cb18b fix hte last remaining known (by me) phi translation bug. When we reanalyze
clobbers to forward pieces of large stores to small loads, we need to consider
the properly phi translated pointer in the store block.

llvm-svn: 90978
2009-12-09 18:21:46 +00:00
Chris Lattner f8ba1253f1 change GetStoreValueForLoad to use IRBuilder, which is cleaner and
implicitly constant folds.

llvm-svn: 90977
2009-12-09 18:13:28 +00:00
Bob Wilson 1c5a6fb299 Fix a comment.
llvm-svn: 90975
2009-12-09 18:05:27 +00:00
Chris Lattner 07df9efb35 change AnalyzeLoadFromClobberingMemInst/AnalyzeLoadFromClobberingStore
to require the load ty/ptr to be passed in, no functionality change.

llvm-svn: 90960
2009-12-09 07:37:07 +00:00
Chris Lattner 0def861ee9 change AnalyzeLoadFromClobberingWrite and clients to pass in type
and pointer instead of the load.  No functionality change.

llvm-svn: 90959
2009-12-09 07:34:10 +00:00
Chris Lattner 0c31547168 change NonLocalDepEntry from being a typedef for an std::pair to be its
own small class.  No functionality change.

llvm-svn: 90956
2009-12-09 07:08:01 +00:00
Chris Lattner 946b58dd90 add some aborts to #if 0's.
llvm-svn: 90929
2009-12-09 02:41:54 +00:00
Chris Lattner 972e6d8d00 Switch GVN and memdep to use PHITransAddr, which correctly handles
phi translation of complex expressions like &A[i+1].  This has the
following benefits:

1. The phi translation logic is all contained in its own class with
   a strong interface and verification that it is self consistent.

2. The logic is more correct than before.  Previously, if intermediate
   expressions got PHI translated, we'd miss the update and scan for
   the wrong pointers in predecessor blocks.  @phi_trans2 is a testcase
   for this.

3. We have a lot less code in memdep.

We can handle phi translation across blocks of things like @phi_trans3,
which is pretty insane :).

This patch should fix the miscompiles of 255.vortex, and I tested it 
with a bootstrap of llvm-gcc, llvm-test and dejagnu of course.

llvm-svn: 90926
2009-12-09 01:59:31 +00:00
Bob Wilson c5d082fd5d Some superficial cleanups.
llvm-svn: 90866
2009-12-08 18:27:03 +00:00
Bob Wilson 2029ea04f9 Clean up dead operands left around after SROA replaces a mem intrinsic.
I'm not aware that this does anything significant on its own, but it's
needed for another patch that I'm working on.

llvm-svn: 90864
2009-12-08 18:22:03 +00:00
Nick Lewycky 8bca014d7f Remove unnecessary #include "llvm/LLVMContext.h".
llvm-svn: 90836
2009-12-08 05:45:41 +00:00
Chris Lattner 6d6f10fe91 fix PR5698
llvm-svn: 90708
2009-12-06 17:17:23 +00:00
Chris Lattner 778cb92235 constant fold loads from memcpy's from global constants. This is important
because clang lowers nontrivial automatic struct/array inits to memcpy from
a global array.

llvm-svn: 90698
2009-12-06 05:29:56 +00:00
Chris Lattner 93236ba327 add support for forwarding mem intrinsic values to non-local loads.
llvm-svn: 90697
2009-12-06 04:54:31 +00:00
Chris Lattner 42376066eb Handle forwarding local memsets to loads. For example, we optimize this:
short x(short *A) {
  memset(A, 1, sizeof(*A)*100);
  return A[42];
}

to 'return 257' instead of doing the load.  

llvm-svn: 90695
2009-12-06 01:57:02 +00:00
Nick Lewycky a0e9d700dc Generalize this optimization to work on equality comparisons between any two
integers that are constant except for a single bit (the same n-th bit in each).

llvm-svn: 90646
2009-12-05 05:00:00 +00:00
Bob Wilson 050b812fe7 Fix up some comments.
llvm-svn: 90603
2009-12-04 21:57:37 +00:00