Commit Graph

7218 Commits

Author SHA1 Message Date
Dan Gohman
dc0e8fb9f9 Move SCEV::dominates and properlyDominates to ScalarEvolution.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119570 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 21:41:58 +00:00
Dan Gohman
17ead4ff4b Move SCEV::isLoopInvariant and hasComputableLoopEvolution to be member
functions of ScalarEvolution, in preparation for memoization and
other optimizations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119562 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 21:23:15 +00:00
Dan Gohman
a9b61e7f7b Reference ScalarEvolution by name rather than directly in LICM,
to avoid an unneeded dependence.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119557 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 20:50:07 +00:00
Benjamin Kramer
1951a5b721 InstCombine: Add a missing irem identity (X % X -> 0).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119538 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 19:11:46 +00:00
Duncan Sands
2b749870d0 Move some those Xor simplifications which don't require creating new
instructions out of InstCombine and into InstructionSimplify.  While
there, introduce an m_AllOnes pattern to simplify matching with integers
and vectors with all bits equal to one.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119536 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 18:52:15 +00:00
Duncan Sands
6fb881c036 Have InlineFunction use SimplifyInstruction rather than
hasConstantValue.  I was leery of using SimplifyInstruction
while the IR was still in a half-baked state, which is the
reason for delaying the simplification until the IR is fully
cooked.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119494 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 11:16:23 +00:00
Duncan Sands
6ac3386e10 Have RemovePredecessorAndSimplify you SimplifyInstruction
rather than hasConstantValue.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119457 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 04:12:05 +00:00
Duncan Sands
d32c4a1756 Remove dead code in GVN: now that SimplifyInstruction is called
systematically, CollapsePhi will always return null here.  Note
that CollapsePhi did an extra check, isSafeReplacement, which
the SimplifyInstruction logic does not do.  I think that check
was bogus - I guess we will soon find out!  (It was originally
added in commit 41998 without a testcase).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119456 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 04:05:21 +00:00
Duncan Sands
cdbd992622 Have a few places that want to simplify phi nodes use SimplifyInstruction
rather than calling hasConstantValue.  No intended functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119352 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-16 17:41:24 +00:00
Duncan Sands
eff0581583 If dom tree information is available, make it possible to pass
it to get better phi node simplification.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119055 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-14 18:36:10 +00:00
Duncan Sands
cd6636c737 Teach InstructionSimplify about phi nodes. I chose to have it simply
offload the work to hasConstantValue rather than do something more
complicated (such handling mutually recursive phis) because (1) it is
not clear it is worth it; and (2) if it is worth it, maybe such logic
would be better placed in hasConstantValue.  Adjust some GVN tests
which are now cleaned up much further (eg: all phi nodes are removed).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119043 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-14 13:30:18 +00:00
Duncan Sands
096aa79276 Generalize the reassociation transform in SimplifyCommutative (now renamed to
SimplifyAssociativeOrCommutative) "(A op C1) op C2" -> "A op (C1 op C2)",
which previously was only done if C1 and C2 were constants, to occur whenever
"C1 op C2" simplifies (a la InstructionSimplify).  Since the simplifying operand
combination can no longer be assumed to be the right-hand terms, consider all of
the possible permutations.  When compiling "gcc as one big file", transform 2
(i.e. using right-hand operands) fires about 4000 times but it has to be said
that most of the time the simplifying operands are both constants.  Transforms
3, 4 and 5 each fired once.  Transform 6, which is an existing transform that
I didn't change, never fired.  With this change, the testcase is now optimized
perfectly with one run of instcombine (previously it required instcombine +
reassociate + instcombine, and it may just have been luck that this worked).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119002 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-13 15:10:37 +00:00
Duncan Sands
88c3df7afb Have GVN simplify instructions as it goes. For example, consider
"%z = %x and %y".  If GVN can prove that %y equals %x, then it turns
this into "%z = %x and %x".  With the new code, %z will be replaced
with %x everywhere (and then deleted).  Previously %z would be value
numbered too, which is a waste of time.  Also, while a clever value
numbering algorithm would give %z the same value number as %x, our
current one doesn't do so (at least I don't think it does).  The new
logic has an essentially equivalent effect to what you would get if
%z was given the same value number as %x, i.e. it should make value
numbering smarter.  While there, get hold of target data once at the
start rather than a gazillion times all over the place.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118923 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-12 21:10:24 +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
6d8eb156e6 Add helper functions for computing the Location of load, store,
and vaarg instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118845 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-11 21:50:19 +00:00
Dan Gohman
4d70a29490 Factor out Instruction::isSafeToSpeculativelyExecute's code for
testing for dereferenceable pointers into a helper function,
isDereferenceablePointer.  Teach it how to reason about GEPs
with simple non-zero indices.

Also eliminate ArgumentPromtion's IsAlwaysValidPointer,
which didn't check for weak externals or out of range gep
indices.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118840 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-11 21:23:25 +00:00
Dan Gohman
56653f0df8 TBAA-enable ArgumentPromotion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118804 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-11 18:09:32 +00:00
Dan Gohman
5aae3dcb53 Make Sink tbaa-aware.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118788 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-11 16:21:47 +00:00
Dan Gohman
2c71f18ff7 It's safe to sink some instructions which are not safe to speculatively
execute. Make Sink's predicate more precise.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118787 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-11 16:20:28 +00:00
Dan Gohman
075fb5d68f Enhance GVN to do more precise alias queries for non-local memory
references. For example, this allows gvn to eliminate the load in
this example:

  void foo(int n, int* p, int *q) {
    p[0] = 0;
    p[1] = 1;
    if (n) {
      *q = p[0];
    }
  }


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118714 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10 20:37:15 +00:00
Dan Gohman
3355c4e598 Use getValueOperand() and getPointerOperand() on load and store
instructions instead of hard-coding operand numbers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118698 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10 19:03:33 +00:00
Dan Gohman
68a6056daf Add a doesAccessArgPointees helper function, and update code to use
it, and to be consistent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118692 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10 18:17:28 +00:00
Dan Gohman
432d08cbdb Factor out the code for testing whether a function accesses
arbitrary memory into a helper function, and adjust some comments.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118687 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10 17:34:04 +00:00
Dale Johannesen
201ab3acff When checking that the necessary bits are zero in
order to reduce ((x<<30)>>24) to x<<6, check the
correct bits.  PR 8547.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118665 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10 01:30:56 +00:00
Dan Gohman
42c31a7073 Make ModRefBehavior a lattice. Use this to clean up AliasAnalysis
chaining and simplify FunctionAttrs' GetModRefBehavior logic.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118660 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10 01:02:18 +00:00
Dan Gohman
4cf0dcfb44 Teach FunctionAttrs about the VAArg instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118627 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-09 20:17:38 +00:00
Dan Gohman
6d44d64f61 Use the AliasAnalysis interface to determine how a Function accesses
memory. This isn't a real improvement with present day AliasAnalysis
implementations; it's mainly for consistency.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118624 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-09 20:13:27 +00:00
Dan Gohman
cd93f3bbb9 Teach LICM and AliasSetTracker about AccessesArgumentsReadonly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118618 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-09 19:58:21 +00:00
Dan Gohman
40b6a19daa Teach FunctionAttrs about AccessesArgumentsReadonly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118617 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-09 19:56:27 +00:00
Dan Gohman
554375b707 Fix a thinko that Duncan spotted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118430 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-08 19:24:47 +00:00
Dan Gohman
ea8900f5df Make FunctionAttrs TBAA-aware.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118417 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-08 17:12:04 +00:00
Dan Gohman
a25e5dbcc2 Extend the AliasAnalysis::pointsToConstantMemory interface to allow it
to optionally look for constant or local (alloca) memory.

Teach BasicAliasAnalysis::pointsToConstantMemory to look through Select
and Phi nodes, and to support looking for local memory.

Remove FunctionAttrs' PointsToLocalOrConstantMemory function, now that
AliasAnalysis knows all the tricks that it knew.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118412 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-08 16:45:26 +00:00
Dan Gohman
3c97f7af9e Make FunctionAttrs use AliasAnalysis::getModRefBehavior, now that it
knows about intrinsic functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118410 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-08 16:10:15 +00:00
Duncan Sands
391f5bce04 Rename PointsToLocalMemory to PointsToLocalOrConstantMemory to make
the code more self-documenting.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118171 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-03 14:45:05 +00:00
Jakob Stoklund Olesen
930f5efac0 Let the -inline-threshold command line argument take precedence over the
threshold given to createFunctionInliningPass().

Both opt -O3 and clang would silently ignore the -inline-threshold option.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118117 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-02 23:40:26 +00:00
Owen Anderson
648b20d5db When folding away a (shl (shr)) pair, we need to check that the bits that will BECOME the low
bits are zero, not that the current low bits are zero.  Fixes <rdar://problem/8606771>.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117953 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-01 21:08:20 +00:00
Duncan Sands
aa66099330 Now that the MallocInst no longer exists, this workaround for
it claiming not to have side-effects is no longer needed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117789 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-30 16:12:16 +00:00
Duncan Sands
ad6f541840 If a function does a volatile load from a global constant, do not
consider it to be readonly.  In fact, don't even consider it to be
readonly if it does a volatile load from an AllocaInst either (it
is debatable as to whether readonly would be correct or not in this
case; play safe for the moment).  This fixes PR8279.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117783 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-30 12:59:44 +00:00
Bob Wilson
db1da8ed42 Clean up indentation and other whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117728 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 22:20:45 +00:00
Bob Wilson
09fd64644d Remove trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117727 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 22:20:43 +00:00
Bob Wilson
f0b48f836e Fix 80-column violation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117722 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 22:03:07 +00:00
Bob Wilson
822cb58d08 Change instcombine's getShuffleMask to represent undef with negative values.
This code had previously used 2*N, where N is the mask length, to represent
undef.  That is not safe because the shufflevector operands may have more
than N elements -- they don't have to match the result type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117721 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 22:03:05 +00:00
Bob Wilson
4cac5facc3 Make instcombine a little more aggressive in combining vector shuffles.
Allow splats even if they don't match either of the original shuffles,
possibly due to undef entries in the shuffles masks.  Radar 8597790.
Also fix some 80-column violations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117719 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 22:02:50 +00:00
Owen Anderson
0995f20cfd Give up on doing in-line instruction simplification during correlated value propagation. Instruction simplification
needs to be guaranteed never to be run on an unreachable block.  However, earlier block simplifications may have
changed the CFG to make block that were reachable when we began our iteration unreachable by the time we try to
simplify them. (Note that this also means that our depth-first iterators were potentially being invalidated).

This should not have a large impact on code quality, since later runs of instcombine should pick up these simplifications.
Fixes PR8506.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117709 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 21:05:17 +00:00
John Thompson
44ab89eb37 Inline asm multiple alternative constraints development phase 2 - improved basic logic, added initial platform support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117667 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 17:29:13 +00:00
Dale Johannesen
f514f52790 Teach InstCombine not to use Add and Neg on FP. PR 8490.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117510 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-27 23:45:18 +00:00
Dan Gohman
17a0bf996f Fix a case where instcombine was stripping metadata (and alignment)
from stores when folding in bitcasts.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117265 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-25 16:16:27 +00:00
Duncan Sands
5f28475b30 Fix PR8445: a block with no predecessors may be the entry block, in which case
it isn't unreachable and should not be zapped.  The check for the entry block
was missing in one case: a block containing a unwind instruction.  While there,
do some small cleanups: "M" is not a great name for a Function* (it would be
more appropriate for a Module*), change it to "Fn"; use Fn in more places.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117224 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-24 12:23:30 +00:00
Benjamin Kramer
a53fe6070c SmallVectorize.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117213 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-23 17:10:24 +00:00
Chandler Carruth
100c267249 Switch attribute macros to use 'LLVM_' as a prefix. We retain the old names
until other LLVM projects using these are cleaned up.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117200 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-23 08:10:43 +00:00