Commit Graph

2230 Commits

Author SHA1 Message Date
Owen Anderson
4a7893b452 Add a parent pointer to SCEV, in preparation for getting rid of the global uniquing tables. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73728 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 22:25:12 +00:00
Dan Gohman
30fb512e95 Recognize n != 0 ? n : 1 as umax(n, 1). Previously only ULT/UGT/ULE/UGE
comparisons were recognized for umax, but instcombine canonicalizes
unsigned comparisons with zero to this simpler form.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73717 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 20:21:07 +00:00
Dan Gohman
4e8a98519e Remove the code from IVUsers that attempted to handle
casted induction variables in cases where the cast
isn't foldable. It ended up being a pessimization in
many cases. This could be fixed, but it would require
a bunch of complicated code in IVUsers' clients. The
advantages of this approach aren't visible enough to
justify it at this time.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73706 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 16:54:06 +00:00
Dan Gohman
6864db6fac Update a comment to reflect the code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73704 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 16:24:47 +00:00
Dan Gohman
9e7d9883b0 Fix trailing whitespace from ScalarEvolution::print.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73666 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 00:37:45 +00:00
Dan Gohman
820528331f Teach ScalarEvolution how to recognize another xor(and(x, C), C) case.
If C is a single bit and the and gets analyzed as a truncate and
zero-extend, the xor can be represnted as an add.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73664 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 00:00:20 +00:00
Dan Gohman
fc3641b07a Delete unnecessary braces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73663 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 23:54:37 +00:00
Dan Gohman
3034c10675 Fix ScalarEvolution's Xor handling to not assume that an And
that gets recognized with a SCEVZeroExtendExpr must be an And
with a low-bits mask. With r73540, this is no longer the case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73594 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 01:22:39 +00:00
Dan Gohman
61ffa8e373 Instcombine's ShrinkDemandedConstant may strip bits out of constants,
obscuring what would otherwise be a low-bits mask.  Use ComputeMaskedBits
to compute what ShrinkDemandedConstant knew about to reconstruct a
low-bits mask value.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73540 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-16 19:52:01 +00:00
Dan Gohman
6de29f8d96 Support vector casts in more places, fixing a variety of assertion
failures.

To support this, add some utility functions to Type to help support
vector/scalar-independent code. Change ConstantInt::get and
ConstantFP::get to support vector types, and add an overload to
ConstantInt::get that uses a static IntegerType type, for
convenience.

Introduce a new getConstant method for ScalarEvolution, to simplify
common use cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73431 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-15 22:12:54 +00:00
Dan Gohman
743e41eae1 Code cleanups. getSCEVAtScope no longer uses SCEVCouldNotCompute.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73401 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-15 18:38:59 +00:00
Dan Gohman
a119de86a0 Fix old-style type names in comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73362 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-14 23:30:43 +00:00
Dan Gohman
bd59d7b603 Implement more aggressive folding of add operand lists when
they contain multiplications of constants with add operations.
This helps simplify several kinds of things; in particular it
helps simplify expressions like ((-1 * (%a + %b)) + %a) to %b,
as expressions like this often come up in loop trip count
computations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73361 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-14 22:58:51 +00:00
Dan Gohman
7f7c4366ca Check for the short-circuiting condition before performing
the potentially expensive erase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73359 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-14 22:53:57 +00:00
Dan Gohman
4dfad29547 Do compare constant SCEV values in SCEVComplexityCompare, because
even though the order doesn't matter at the top level of an expression,
it does matter when the constant is a subexpression of an n-ary
expression, because n-ary expressions are sorted lexicographically.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73358 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-14 22:51:25 +00:00
Dan Gohman
a82752c9eb Convert several parts of the ScalarEvolution framework to use
SmallVector instead of std::vector.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73357 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-14 22:47:23 +00:00
Dan Gohman
4d8414f420 Teach SCEVExpander's visitAddRecExpr to reuse an existing canonical
induction variable when the addrec to be expanded does not require
a wider type. This eliminates the need for IndVarSimplify to
micro-manage SCEV expansions, because SCEVExpander now
automatically expands them in the form that IndVarSimplify considers
to be canonical. (LSR still micro-manages its SCEV expansions,
because it's optimizing for the target, rather than for
other optimizations.)

Also, this uses the new getAnyExtendExpr, which has more clever
expression simplification logic than the IndVarSimplify code it
replaces, and this cleans up some ugly expansions in code such as
the included masked-iv.ll testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73294 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-13 16:25:49 +00:00
Dan Gohman
2ce84c8d47 Add a ScalarEvolution::getAnyExtendExpr utility function for performing
extension with unspecified bits.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73293 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-13 15:56:47 +00:00
Dan Gohman
92fcdcac54 Use expandCodeFor instead of expand when the result will be
immediately casted. At present, this is just a minor code
simplification. In the future, the expansion code may be able
to make better choices if it knows what the desired result
type will be.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73137 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-09 17:18:38 +00:00
Dan Gohman
86fbf2fe4c Rename UnknownValue to CouldNotCompute, since it holds an instance of
SCEVCouldNotCompute, and not SCEVUnknown.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72999 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-06 14:37:11 +00:00
Devang Patel
5c06f61e57 Simplify.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72970 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-05 23:08:56 +00:00
Dan Gohman
1d09de3eca Move SCEVExpander::getOrInsertCanonicalInductionVariable out of line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72949 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-05 16:35:53 +00:00
Dan Gohman
c965ee223c Remove some unnecessary #includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72948 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-05 16:32:58 +00:00
Dan Gohman
ae3a0be92e Split the Add, Sub, and Mul instruction opcodes into separate
integer and floating-point opcodes, introducing
FAdd, FSub, and FMul.

For now, the AsmParser, BitcodeReader, and IRBuilder all preserve
backwards compatability, and the Core LLVM APIs preserve backwards
compatibility for IR producers. Most front-ends won't need to change
immediately.

This implements the first step of the plan outlined here:
http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72897 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-04 22:49:04 +00:00
Dan Gohman
7714285efd Change ConstantFoldConstantExpression to accept a null
TargetData pointer. The only thing it's used for are
calls to ConstantFoldCompareInstOperands and
ConstantFoldInstOperands, which both already accept a
null TargetData pointer. This makes
ConstantFoldConstantExpression easier to use in clients
where TargetData is optional.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72741 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-02 21:48:15 +00:00
Dan Gohman
18a69c5a36 Delete an obsolete sentance from a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72667 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-31 16:18:57 +00:00
Dan Gohman
f1a80489d6 Add braces around an array initializer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72453 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-27 02:07:15 +00:00
Dan Gohman
4a4f767235 Teach SCEVExpander to avoid creating over-indexed GEP indices when
possible. For example, it now emits

  %p.2.ip.1 = getelementptr [3 x [3 x double]]* %p, i64 2, i64 %tmp, i64 1

instead of the equivalent but less obvious

  %p.2.ip.1 = getelementptr [3 x [3 x double]]* %p, i64 0, i64 %tmp, i64 19


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72452 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-27 02:00:53 +00:00
Dan Gohman
72776d2190 Teach BasicAliasAnalysis to understand constant gep indices that fall
beyond their associated static array type.

I believe that this fixes a legitimate bug, because BasicAliasAnalysis
already has code to check for this condition that works for non-constant
indices, however it was missing the case of constant indices. With this
change, it checks for both.

This fixes PR4267, and miscompiles of SPEC 188.ammp and 464.h264.href.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72451 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-27 01:48:27 +00:00
Dan Gohman
91bb61a1e2 For the return type of SCEVUDivExpr, use the RHS' type instead of
that of the LHS. It doesn't matter for correctness, but the LHS
is more likely than the RHS to be a pointer type in exotic cases,
and it's more tidy to have it return the integer type.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72424 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-26 17:44:05 +00:00
Dan Gohman
f876ad0a70 In cases where a pointer value is an operand of a multiplication or
division operation, don't attempt to use the operation's value as
the base of a getelementptr. This fixes PR4271.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72422 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-26 17:41:16 +00:00
Chris Lattner
ab9cf1282b make memdep use the getModRefInfo method for stores instead of the
low-level alias() method, allowing it to reason more aggressively
about pointers into constant memory.  PR4189


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72403 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-25 21:28:56 +00:00
Dan Gohman
6c0866ca83 Various comment fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72376 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-24 23:45:28 +00:00
Dan Gohman
d594e6f034 Change ScalarEvolution::getSCEVAtScope to always return the original value
in the case where a loop exit value cannot be computed, instead of only in
some cases while using SCEVCouldNotCompute in others. This simplifies
getSCEVAtScope's callers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72375 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-24 23:25:42 +00:00
Torok Edwin
3790fb0c03 Instead of clearing the rewriter, don't attempt to rewrite dead phi nodes.
Also fix 80 column violation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72371 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-24 19:36:09 +00:00
Dan Gohman
fb5a3419f3 Fix this code for hosts where std::vector doesn't have .data().
Use &Ops[0] instead, which is safe since Ops will never be empty here.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72368 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-24 19:02:45 +00:00
Dan Gohman
453aa4fbf1 Generalize SCEVExpander::visitAddRecExpr's GEP persuit, and avoid
sending SCEVUnknowns to expandAddToGEP. This avoids the need for
expandAddToGEP to bend the rules and peek into SCEVUnknown
expressions.

Factor out the code for testing whether a SCEV can be factored by
a constant for use in a GEP index. This allows it to handle
SCEVAddRecExprs, by recursing.

As a result, SCEVExpander can now put more things in GEP indices,
so it emits fewer explicit mul instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72366 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-24 18:06:31 +00:00
Dan Gohman
3925043af0 When the low bits of one operand of an add are zero, that number
of low bits of the other operand are preserved in the output.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72365 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-24 18:02:35 +00:00
Torok Edwin
b679de2a21 The rewriter may hold references to instructions that are deleted because they are trivially dead.
Fix by clearing the rewriter cache before deleting the trivially dead
instructions.
Also make InsertedExpressions use an AssertingVH to catch these
bugs easier.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72364 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-24 14:23:16 +00:00
Dan Gohman
0d56b06f86 Fix a thinko in the code that adapted SCEVMulExpr operands for
use in expanding SCEVAddExprs with GEPs. The operands of a
SCEVMulExpr need to be multiplied together, not added.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72250 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-22 07:14:20 +00:00
Jay Foad
e3e51c0038 Use v.data() instead of &v[0] when SmallVector v might be empty.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72210 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-21 09:52:38 +00:00
Dan Gohman
9004c8afd4 Teach ValueTracking a new way to analyze PHI nodes, and and teach
Instcombine to be more aggressive about using SimplifyDemandedBits
on shift nodes. This allows a shift to be simplified to zero in the
included test case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72204 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-21 02:28:33 +00:00
Dan Gohman
a3035a69f9 Teach SCEV::isLoopInvariant and SCEV::hasComputableLoopEvolution
about the convention from LoopInfo that a null Loop* means the entire
function body.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72152 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-20 01:01:24 +00:00
Dan Gohman
1959b7562e Make SCEVCallbackVH a private nested class inside ScalarEvolution, as
it's an implementation detail.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72122 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-19 19:22:47 +00:00
Dan Gohman
278b49af8a Create ConstantExpr GEPs the correct way. This fixes
MultiSource/Benchmarks/Prolangs-C/football and a variety of other
failures.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72120 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-19 19:18:01 +00:00
Dan Gohman
5be18e8476 Teach SCEVExpander to expand arithmetic involving pointers into GEP
instructions. It attempts to create high-level multi-operand GEPs,
though in cases where this isn't possible it falls back to casting
the pointer to i8* and emitting a GEP with that. Using GEP instructions
instead of ptrtoint+arithmetic+inttoptr helps pointer analyses that
don't use ScalarEvolution, such as BasicAliasAnalysis.

Also, make the AddrModeMatcher more aggressive in handling GEPs.
Previously it assumed that operand 0 of a GEP would require a register
in almost all cases. It now does extra checking and can do more
matching if operand 0 of the GEP is foldable. This fixes a problem
that was exposed by SCEVExpander using GEPs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72093 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-19 02:15:55 +00:00
Daniel Dunbar
8c562e2d25 Silence Release-Asserts warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72011 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 16:43:04 +00:00
Dan Gohman
10978bd591 Teach ScalarEvolution to recognize x^-1 in the case where non-demanded
bits have been stripped out by instcombine.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72010 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 16:29:04 +00:00
Dan Gohman
0bac95e2e2 Delete a redundant 'else'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72009 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 16:17:44 +00:00
Dan Gohman
8ea94524ed Fix ScalarEvolution::isLoopGuardedByCond to accept a null Loop*, for
consistency with other routines that use a null Loop* to mean code
not contained by any loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72008 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 16:03:58 +00:00