Commit Graph

8567 Commits

Author SHA1 Message Date
Andrew Trick
b5c26ef9da SCEVExpander fixes. Affects LSR and indvars.
LSR has gradually been improved to more aggressively reuse existing code, particularly existing phi cycles. This exposed problems with the SCEVExpander's sloppy treatment of its insertion point. I applied some rigor to the insertion point problem that will hopefully avoid an endless bug cycle in this area. Changes:

- Always used properlyDominates to check safe code hoisting.

- The insertion point provided to SCEV is now considered a lower bound. This is usually a block terminator or the use itself. Under no cirumstance may SCEVExpander insert below this point.

- LSR is reponsible for finding a "canonical" insertion point across expansion of different expressions.

- Robust logic to determine whether IV increments are in "expanded" form and/or can be safely hoisted above some insertion point.

Fixes PR11783: SCEVExpander assert.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148535 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-20 07:41:13 +00:00
Dan Gohman
0cdece4389 Set the "tail" flag on pattern-matched objc_storeStrong calls.
rdar://10531041.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148490 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-19 19:14:36 +00:00
Nick Lewycky
f460bf8cd8 Actually, this code handles wrapped sets just fine. Noticed by inspection.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148487 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-19 18:19:42 +00:00
Dan Gohman
2f77bbd1bf Add a depth limit to avoid runaway recursion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148419 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-18 21:24:45 +00:00
Dan Gohman
1dae3e965c Use llvm.global_ctors to locate global constructors instead
of recognizing them by name.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148416 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-18 21:19:38 +00:00
Jakub Staszak
785a7a97da Remove trailing spaces and unneeded includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148415 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-18 21:16:33 +00:00
Dan Gohman
2f6263c96a Add a new ObjC ARC optimization pass to eliminate unneeded
autorelease push+pop pairs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148330 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-17 20:52:24 +00:00
Dan Gohman
7d4c87ef6e Add a new PassManagerBuilder customization point,
EP_ModuleOptimizerEarly, to allow passes to be added before the
main ModulePass optimizers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148329 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-17 20:51:32 +00:00
Andrew Trick
0f080913d1 LSR fix: broaden the check for loop preheaders.
It's becoming clear that LoopSimplify needs to unconditionally create loop preheaders. But that is a bigger fix. For now, continuing to hack LSR.
Fixes rdar://10701050 "Cannot split an edge from an IndirectBrInst" assert.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148288 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-17 06:45:52 +00:00
David Blaikie
fdebc38523 Remove unreachable code. (replace with llvm_unreachable to help GCC where necessary)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148284 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-17 04:43:56 +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
Dan Gohman
92180988a4 Fix an unused variable warning that Chad noticed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148164 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-14 00:47:44 +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
Dan Gohman
79522dc569 Implement proper ObjC ARC objc_retainBlock "escape" analysis, so that
the optimizer doesn't eliminate objc_retainBlock calls which are needed
for their side effect of copying blocks onto the heap.
This implements rdar://10361249.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148076 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-13 00:39:07 +00:00
Eli Friedman
e15f421a9a Re-fix the issue Bill fixed in r147899 in a slightly different way, which doesn't abuse the semantics of linker_private. We don't really want to merge any string constant with a weak_odr global.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147971 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-11 22:06:46 +00:00
Kostya Serebryany
bcb55ce386 [asan] extend the workaround for http://llvm.org/bugs/show_bug.cgi?id=11395: don't instrument the function at all on x86_32 if it has a large asm blob
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147953 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-11 18:15:23 +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
Bill Wendling
37b94c6b4e If the global variable is removed by the linker, then don't constant merge it
with other symbols.

An object in the __cfstring section is suppoed to be filled with CFString
objects, which have a pointer to ___CFConstantStringClassReference followed by a
pointer to a __cstring. If we allow the object in the __cstring section to be
merged with another global, then it could end up in any section. Because the
linker is going to remove these symbols in the final executable, we shouldn't
bother to merge them.
<rdar://problem/10564621>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147899 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-11 00:13:08 +00:00
Andrew Trick
64925c55c6 Enable LSR IV Chains with sufficient heuristics.
These heuristics are sufficient for enabling IV chains by
default. Performance analysis has been done for i386, x86_64, and
thumbv7. The optimization is rarely important, but can significantly
speed up certain cases by eliminating spill code within the
loop. Unrolled loops are prime candidates for IV chains. In many
cases, the final code could still be improved with more target
specific optimization following LSR. The goal of this feature is for
LSR to make the best choice of induction variables.

Instruction selection may not completely take advantage of this
feature yet. As a result, there could be cases of slight code size
increase.

Code size can be worse on x86 because it doesn't support postincrement
addressing. In fact, when chains are formed, you may see redundant
address plus stride addition in the addressing mode. GenerateIVChains
tries to compensate for the common cases.

On ARM, code size increase can be mitigated by using postincrement
addressing, but downstream codegen currently misses some opportunities.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147826 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-10 01:45:08 +00:00
Andrew Trick
22d20c218a Adding IV chain generation to LSR.
After collecting chains, check if any should be materialized. If so,
hide the chained IV users from the LSR solver. LSR will only solve for
the head of the chain. GenerateIVChains will then materialize the
chained IV users by computing the IV relative to its previous value in
the chain.

In theory, chained IV users could be exposed to LSR's solver. This
would be considerably complicated to implement and I'm not aware of a
case where we need it. In practice it's more important to
intelligently prune the search space of nontrivial loops before
running the solver, otherwise the solver is often forced to prune the
most optimal solutions. Hiding the chained users does this well, so
that LSR is more likely to find the best IV for the chain as a whole.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147801 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-09 21:18:52 +00:00
Andrew Trick
6c7d0ae8dc Adding collection of IV chains to LSR.
This collects a set of IV uses within the loop whose values can be
computed relative to each other in a sequence. Following checkins will
make use of this information.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147797 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-09 19:50:34 +00:00
Andrew Trick
8bf295b1bf "Minor LSR debugging stuff"
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147785 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-09 18:58:16 +00:00
Benjamin Kramer
7e4ac32a4e Move assert to the right place.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147779 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-09 17:36:29 +00:00
Benjamin Kramer
47a8607721 InstCombine: Teach foldLogOpOfMaskedICmpsHelper that sign bit tests are bit tests.
This subsumes several other transforms while enabling us to catch more cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147777 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-09 17:23:27 +00:00
Benjamin Kramer
d4242d8ab1 Tweak my last commit to be less conservative about uses.
We still save an instruction when just the "and" part is replaced.
Also change the code to match comments more closely.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147753 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-08 21:12:51 +00:00
Benjamin Kramer
dfb806f6ba InstCombine: If we have a bit test and a sign test anded/ored together, merge the sign bit into the bit test.
This is common in bit field code, e.g. checking if the first or the last bit of a bit field is set.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147749 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-08 18:32:24 +00:00
Andrew Trick
24f670f1ba Enable redundant phi elimination after LSR.
This will be more important as we extend the LSR pass in ways that don't rely on the formula solver. In particular, we need it for constructing IV chains.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147724 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-07 07:08:17 +00:00
Andrew Trick
acdb4aaf9b LSR: Don't optimize loops if an outer loop has no preheader.
LoopSimplify may not run on some outer loops, e.g. because of indirect
branches. SCEVExpander simply cannot handle outer loops with no preheaders.
Fixes rdar://10655343 SCEVExpander segfault.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147718 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-07 03:16:50 +00:00
Andrew Trick
f231a6dc7f LSR: run DeleteDeadPhis before replaceCongruentPhis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147711 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-07 01:36:44 +00:00
Andrew Trick
ee98aa8743 Extended replaceCongruentPhis to handle mixed phi types.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147707 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-07 01:12:09 +00:00
Kostya Serebryany
3c7faae346 [asan] cleanup: remove the SIGILL-related code (compiler part)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147667 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-06 18:09:21 +00:00
Dan Gohman
3b205175ea Fix SpeculativelyExecuteBB to either speculate all or none of the phis
present in the bottom of the CFG triangle, as the transformation isn't
ever valuable if the branch can't be eliminated.

Also, unify some heuristics between SimplifyCFG's multiple
if-converters, for consistency.

This fixes rdar://10627242.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147630 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-05 23:58:56 +00:00
Eli Friedman
fb54ad19e7 PR11705, part 2: globalopt shouldn't put inttoptr/ptrtoint operations into global initializers if there's an implied extension or truncation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147625 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-05 23:03:32 +00:00
Dan Gohman
dd35df15a2 Revert r56315. When the instruction to speculate is a load, this
code can incorrectly move the load across a store. This never
happens in practice today, but only because the current
heuristics accidentally preclude it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147623 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-05 22:54:35 +00:00
Nick Lewycky
720ac91969 SCCCaptured is trivially false on entry to this loop and not modified inside it.
Eliminate the dead test for it on each loop iteration. No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147616 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-05 22:21:45 +00:00
Nick Lewycky
234f8c9ef8 Remove pointless asserts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147529 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-04 09:42:30 +00:00
Nick Lewycky
148fd55ef3 Teach instcombine all sorts of great stuff about shifts that have exact, nuw or
nsw bits on them.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147528 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-04 09:28:29 +00:00
Nick Lewycky
57ed0948b8 Make use of the exact bit when optimizing '(X >>exact 3) << 1' to eliminate the
'and' that would zero out the trailing bits, and to produce an exact shift
ourselves.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147391 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-31 21:30:22 +00:00
Nick Lewycky
b48a18903a Change CaptureTracking to pass a Use* instead of a Value* when a value is
captured. This allows the tracker to look at the specific use, which may be
especially interesting for function calls.

Use this to fix 'nocapture' deduction in FunctionAttrs. The existing one does
not iterate until a fixpoint and does not guarantee that it produces the same
result regardless of iteration order. The new implementation builds up a graph
of how arguments are passed from function to function, and uses a bottom-up walk
on the argument-SCCs to assign nocapture. This gets us nocapture more often, and
does so rather efficiently and independent of iteration order.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147327 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-28 23:24:21 +00:00
Nick Lewycky
8da7ddf2d2 Demystify this comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147307 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-28 06:57:32 +00:00
Nick Lewycky
91968489d7 Use false not zero, as a bool.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147292 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-27 18:27:22 +00:00
Nick Lewycky
a6b21ea4ba Turn cos(-x) into cos(x). Patch by Alexander Malyshev!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147291 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-27 18:25:50 +00:00
Nick Lewycky
06cc66f65a Teach simplifycfg to recompute branch weights when merging some branches, and
to discard weights when appropriate. Still more to do (and a new TODO), but
it's a start!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147286 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-27 04:31:52 +00:00
Rafael Espindola
125ef76934 Fix warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147284 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-26 23:12:42 +00:00
Nick Lewycky
c9a1aed7fe Update the branch weight metadata when reversing the order of a branch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147280 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-26 20:54:14 +00:00
Nick Lewycky
9d52310222 Sort includes, canonicalize whitespace, fix typos. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147279 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-26 20:37:40 +00:00