Commit Graph

441 Commits

Author SHA1 Message Date
Dan Gohman
a15ec5dfcc Don't track users of undef values; they aren't interesting for
register pressure.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105501 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-04 23:16:05 +00:00
Dan Gohman
0fe46d9b48 DominatorTree.getNode can return null for unreachable blocks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104290 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 22:46:54 +00:00
Dan Gohman
9f383eb950 Minor code cleanups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104287 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 22:25:20 +00:00
Dan Gohman
a552878508 Make Solve check its own post-condition, to reduce clutter in the
top-level LSRInstance logic.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104278 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 20:59:23 +00:00
Dan Gohman
76c315a26c Add comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104276 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 20:52:00 +00:00
Dan Gohman
402d43529c More code cleanups. Use iterators instead of indices when indices
aren't needed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104273 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 20:33:18 +00:00
Dan Gohman
c6519f916b Fix OptimizeShadowIV to set Changed. Change OptimizeLoopTermCond to set
Changed directly instead of using a return value.

Rename FilterOutUndesirableDedicatedRegisters's Changed variable to
distinguish it from LSRInstance's Changed member.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104269 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 20:05:31 +00:00
Dan Gohman
f7ff37d674 Add some comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104268 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 20:00:41 +00:00
Dan Gohman
d974a0e9d6 Simplify this code. Don't do a DomTreeNode lookup for each visited block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104267 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 20:00:25 +00:00
Dan Gohman
ea507f5c28 Minor code cleanups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104263 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 19:44:23 +00:00
Dan Gohman
f182b23f8f When canonicalizing icmp operand order to put the loop invariant
operand on the left, the interesting operand is on the right. This
fixes a bug where LSR was failing to recognize ICmpZero uses,
which led it to be unable to reverse the induction variable in the
attached testcase.

Delete test/CodeGen/X86/stack-color-with-reg-2.ll, because its test
is extremely fragile and hard to meaningfully update.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104262 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 19:26:52 +00:00
Dan Gohman
9da1bf4845 Set Changed to true when canonicalizing ICmp operand order; even though
it isn't a very interesting change, it's a change nonetheless.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104260 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 19:16:03 +00:00
Dan Gohman
24a7c30822 Rename a variable to avoid shadowing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104234 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 16:41:11 +00:00
Dan Gohman
4766744072 Minor code simplification.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104232 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 16:23:28 +00:00
Dan Gohman
5ce6d05ad6 Move the code for deleting BaseRegs and LSRUses into helper functions,
and fix a bug that valgrind noticed where the code would std::swap an
element with itself.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104225 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 15:17:54 +00:00
Dan Gohman
a2086b3483 Teach LSR how to cope better with unrolled loops on targets where
the addressing modes don't make this trivially easy. This allows
it to avoid falling into the less precise heuristics in more
cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104186 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-19 23:43:12 +00:00
Dan Gohman
57aaa0b264 Add a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104089 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 23:55:57 +00:00
Dan Gohman
360026f07f Fix the predicate which checks for non-sensical formulae which have
constants in registers which partially cancel out their immediate fields.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104088 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 23:48:08 +00:00
Dan Gohman
b2df433f71 Factor out the code for recomputing an LSRUse's Regs set after some
of its formulae have been removed into a helper function, and also
teach it how to update the RegUseTracker.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104087 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 23:42:37 +00:00
Dan Gohman
d079c300ed Factor out code for estimating search space complexity into a helper
function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104082 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 22:51:59 +00:00
Dan Gohman
0da751baf7 Add some more debug output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104080 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 22:41:32 +00:00
Dan Gohman
d69d62833a Factor out the code for deleting a formula from an LSRUse into
a helper function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104079 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 22:39:15 +00:00
Dan Gohman
6458ff9230 Make some debug output more informative.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104078 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 22:37:37 +00:00
Dan Gohman
c4cfbaf217 Print an error message in Formula::print if the HasBaseReg flag
is inconsistent with the BaseRegs field. It's not print's job to
assert on an invalid condition, but it can make one more obvious.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104077 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 22:35:55 +00:00
Dan Gohman
90bb355b16 Rename RegUseTracker's RegUses member to RegUsesMap to avoid
confusion with LSRInstance's RegUses member.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104076 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 22:33:00 +00:00
Douglas Gregor
7d9663c70b Fixes for Microsoft Visual Studio 2010, from Steven Watanabe!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103457 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-11 06:17:44 +00:00
Dan Gohman
59dc60337f When pruning candidate formulae out of an LSRUse, update the
LSRUse's Regs set after all pruning is done, rather than trying
to do it on the fly, which can produce an incomplete result.

This fixes a case where heuristic pruning was stripping all
formulae from a use, which led the solver to enter an infinite
loop.

Also, add a few asserts to diagnose this kind of situation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103328 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-07 23:36:59 +00:00
Dan Gohman
deff621abd Use getConstant instead of getIntegerSCEV. The two are basically the
same, now that getConstant has overloads consistent with ConstantInt::get.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102965 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-03 22:09:21 +00:00
Dan Gohman
1d367988e2 Generalize LSR's OptimizeMax to handle the new kinds of max expressions
that indvars may use, now that indvars is recognizing le and ge loops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102235 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-24 03:13:44 +00:00
Dan Gohman
fafb890ee2 Fix LSR to tolerate cases where ScalarEvolution initially
misses an opportunity to fold add operands, but folds them
after LSR has separated them out. This fixes rdar://7886751.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102157 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-23 01:55:05 +00:00
Dan Gohman
c056454ecf Remove the Expr member from IVUsers. Instead of remembering the expression,
just ask ScalarEvolution for it on demand. This helps IVUsers be more robust
in the case of expressions changing underneath it. This fixes PR6862.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101819 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-19 21:48:58 +00:00
Dan Gohman
ef817ccec4 Delete this code, which is no longer needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101033 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-12 08:00:22 +00:00
Dan Gohman
e5f76877ae When determining a canonical insert position, don't climb deeper
into adjacent loops. Also, ensure that the insert position is
dominated by the loop latch of any loop in the post-inc set which
has a latch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100906 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-09 22:07:05 +00:00
Dan Gohman
4a2a683366 When looking for loop-invariant users, look through no-op instructions,
so that an unfortunately placed bitcast doesn't pin a value in a
register.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100883 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-09 19:12:34 +00:00
Dan Gohman
d96eae8010 Refactor the code for computing the insertion point for an expression into
a separate function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100845 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-09 02:00:38 +00:00
Dan Gohman
e60bb15982 Avoid allocating a value of zero in a register if the initial formula
inputs happen to negate each other.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100828 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-08 23:36:27 +00:00
Dan Gohman
e056781323 Add variants of ult, ule, etc. which take a uint64_t RHS, for convenience.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100824 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-08 23:03:40 +00:00
Dan Gohman
701a4aef7f When expanding expressions which are using post-inc mode for multiple loops,
ensure that the expansion is dominated by the increments of those loops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100748 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-08 05:57:57 +00:00
Dan Gohman
448db1cdef Generalize IVUsers to track arbitrary expressions rather than expressions
explicitly split into stride-and-offset pairs. Also, add the
ability to track multiple post-increment loops on the same expression.

This refines the concept of "normalizing" SCEV expressions used for
to post-increment uses, and introduces a dedicated utility routine for
normalizing and denormalizing expressions.

This fixes the expansion of expressions which are post-increment users
of more than one loop at a time. More broadly, this takes LSR another
step closer to being able to reason about more than one loop at a time.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100699 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-07 22:27:08 +00:00
Dan Gohman
449f31cb9d Ignore debug intrinsics in yet more places.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99580 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-26 00:33:27 +00:00
Gabor Greif
60ad781c61 rename use_const_iterator to const_use_iterator for consistency's sake
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99564 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25 23:06:16 +00:00
Dan Gohman
087bd1e3a1 Make SCEVExpander and LSR more aggressive about hoisting expressions out
of loops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97642 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-03 05:29:13 +00:00
Dan Gohman
069d6f3396 Non-affine post-inc SCEV expansions have more code which must be
emitted after the increment. Make sure the insert position
reflects this. This fixes PR6453.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97537 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-02 01:59:21 +00:00
Dan Gohman
3f46a3abee Spelling fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97453 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-01 17:49:51 +00:00
Dan Gohman
454d26dc43 Remove unused variables and parameters.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96780 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-22 04:11:59 +00:00
Dan Gohman
278f958c61 When emitting an instruction which depends on both a post-incremented
induction variable value and a loop-variant value, don't force the
insert position to be at the post-increment position, because it may
not be dominated by the loop-variant value. This fixes a
use-before-def problem noticed on PPC.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96774 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-22 03:59:54 +00:00
Dan Gohman
f09b71233b Rename getSDiv to getExactSDiv to reflect its behavior in cases where
the division would have a remainder.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96693 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-19 19:35:48 +00:00
Dan Gohman
aae01f17a6 Check for overflow when scaling up an add or an addrec for
scaled reuse.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96692 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-19 19:32:49 +00:00
Dan Gohman
1b7bf18def When determining the set of interesting reuse factors, consider
strides in foreign loops. This helps locate reuse opportunities
with existing induction variables in foreign loops and reduces
the need for inserting new ones. This fixes rdar://7657764.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96629 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-19 00:05:23 +00:00
Dan Gohman
378c0b35a7 Delete some unneeded casts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96429 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-17 00:42:19 +00:00