Commit Graph

454 Commits

Author SHA1 Message Date
Dan Gohman
a9db129730 Don't merge uses when they are targetting fixup sites with
different widths. In a use with a narrower fixup, formulae
may be wider than the fixup, in which case the high bits
aren't necessarily meaningful, so it isn't safe to reuse
them for uses with wider fixups.

This fixes PR7618, though the testcase is too large for a
reasonable regression test, since it heavily dependes on
hitting LSR's heuristics in a certain way.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108455 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 20:24:58 +00:00
Dan Gohman
ef4308d6ba Use dbgs() instead of errs() in a DEBUG.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108453 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 20:12:42 +00:00
Dan Gohman
c88c1a4581 Watch out for a constant offset cancelling out a base register, forming
a zero. This situation arrises in Fortran code with induction variables
that start at 1 instead of 0. This fixes PR7651.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108424 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 15:14:45 +00:00
Gabor Greif
ad72e73136 use getArgOperand instead of getOperand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107270 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-30 09:15:28 +00:00
Dan Gohman
3e3f15bb09 In GenerateReassociations, don't bother thinking about individual
SCEVUnknown values which are loop-variant, as LSR can't do anything
interesting with these values in any case. This fixes very slow compile
times on loops which have large numbers of such values.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106897 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-25 22:32:18 +00:00
Dan Gohman
2ea09e0546 A few minor micro-optimizations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106764 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24 16:57:52 +00:00
Dan Gohman
d42819a07b Teach getExactSDiv to evaluate x/1 to x up front, as it's a common
enough special case, and it theoretically allows more folding because
it works even when x is unanalyzable.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106763 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24 16:51:25 +00:00
Dan Gohman
473e63512a Fix copy+pasto issues in isMulSExtable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106759 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24 16:45:11 +00:00
Dan Gohman
caf71ab473 Fix OptimizeMax to handle an odd case where one of the max operands
is another max which folds. This fixes PR7454.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106594 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-22 23:07:13 +00:00
Dan Gohman
403a8cdda5 Use A.append(...) instead of A.insert(A.end(), ...) when A is a
SmallVector, and other SmallVector simplifications.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106452 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-21 19:47:52 +00:00
Dan Gohman
74e5ef096e Add a TODO comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106397 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-19 21:30:18 +00:00
Dan Gohman
1e3121c80a Include the use kind along with the expression in the key of the
use sharing map. The reconcileNewOffset logic already forces a
separate use if the kinds differ, so incorporating the kind in the
key means we can track more sharing opportunities.

More sharing means fewer total uses to track, which means smaller
problem sizes, which means the conservative throttles don't kick
in as often.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106396 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-19 21:29:59 +00:00
Dan Gohman
b6211710ac Don't include things in anonymous namespaces that don't need it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106395 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-19 21:21:39 +00:00
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