Commit Graph

297 Commits

Author SHA1 Message Date
Dan Gohman
0f4b285a5b Replace the original ad-hoc code for determining whether (v pred w) implies
(x pred y) with more thorough code that does more complete canonicalization
before resorting to range checks. This helps it find more cases where
the canonicalized expressions match.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76671 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21 23:03:19 +00:00
Dan Gohman
19211b47cc Add a testcase for PR4569, which is now fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76526 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21 00:50:52 +00:00
Torok Edwin
969f28dfb6 Introduce a pointertracking pass.
For now this only computes the allocated size of the memory pointed to by a
pointer, and offset a pointer from allocated pointer.
The actual checkLimits part will come later, after another round of review.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75657 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-14 18:44:28 +00:00
Dan Gohman
08d4ec0b20 Add testcases for PR4538, PR4537, and PR4534.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75533 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-13 22:30:31 +00:00
Nick Lewycky
d1ec98923e When comparing constants, consider a less wide constant to be "less complex"
than a wider one, before trying to compare their contents which will crash
if their sizes are different.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74792 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-04 17:24:52 +00:00
Andreas Bolka
e9722fc850 Array accesses are independent if the underlying arrays differ.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74499 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-30 02:12:10 +00:00
Andreas Bolka
c6a303052b Print pairwise dependence results, add testcases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74402 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-28 00:35:22 +00:00
Dan Gohman
e56f4a49b7 Add a testcase demoing some of ScalarEvolution's new trip count logic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74049 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-24 01:22:30 +00:00
Dan Gohman
91380b7239 Fix a bug in the trip-count computation with And/Or. If either of the
sides is CouldNotCompute, the resulting exact count must be CouldNotCompute.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73920 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-22 23:28:56 +00:00
Dan Gohman
bd5ce52740 Fix llvm::ComputeNumSignBits to handle pointer types
conservatively correctly, instead of aborting.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73908 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-22 22:02:32 +00:00
Dan Gohman
a334aa7a10 Teach ScalarEvolution how to analyze loops with multiple exit
blocks, and also exit blocks with multiple conditions (combined
with (bitwise) ands and ors). It's often infeasible to compute an
exact trip count in such cases, but a useful upper bound can often
be found.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73866 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-22 00:31:57 +00:00
Dan Gohman
51f53b7f5a Fix ScalarEvolution's backedge-taken count computations to check for
overflow when computing a integer division to round up.

Thanks to Nick Lewycky for noticing this!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73862 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-21 23:46:38 +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
559254b697 Add -disable-output to a bunch of tests that don't care about the output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73633 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 20:56:26 +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
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
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
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
859b4824ee Make ScalarEvolution::isLoopGuardedByCond work even when the edge
entering a loop is a non-split critical edge.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72004 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 15:36:09 +00:00
Dan Gohman
04623272d2 Add nounwind to a few tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72002 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 15:16:49 +00:00
Eli Friedman
361e54d433 Allow scalar evolution to compute iteration counts for loops with a
pointer-based condition.  This fixes PR3171.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71354 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-09 12:32:42 +00:00
Dan Gohman
b0285932ab Fix bogus overflow checks by replacing them with actual
overflow checks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71284 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-08 23:11:16 +00:00
Dan Gohman
728c7f3059 Fold trunc casts into add-recurrence expressions, allowing the
add-recurrence to be exposed. Add a new SCEV folding rule to
help simplify expressions in the presence of these extra truncs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71264 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-08 21:03:19 +00:00
Dan Gohman
9032b78c98 When printing a SCEVUnknown with pointer type, don't print an
artificial "ptrtoint", as it tends to clutter up complicated
expressions. The cast operators now print both source and
destination types, which is usually sufficient.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70554 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-01 17:02:22 +00:00
Dan Gohman
a1af757e0a Extend ScalarEvolution's getBackedgeTakenCount to be able to
compute an upper-bound value for the trip count, in addition to
the actual trip count. Use this to allow getZeroExtendExpr and
getSignExtendExpr to fold casts in more cases.

This may eventually morph into a more general value-range
analysis capability; there are certainly plenty of places where
more complete value-range information would allow more folding.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70509 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-30 20:47:05 +00:00
Dan Gohman
ac70ceafbc Generalize the cast-of-addrec folding to handle folding of SCEVs like
(sext i8 {-128,+,1} to i64) to i64 {-128,+,1}, where the iteration
crosses from negative to positive, but is still safe if the trip
count is within range.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70421 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29 22:28:28 +00:00
Dan Gohman
3e0e31b261 Fix this test to match the new output from scalar-evolution.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70410 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29 21:06:20 +00:00
Dan Gohman
36b8e53fe0 Include the source type in SCEV cast expression debug output, and
print sext, zext, and trunc, instead of signextend, zeroextend,
and truncate, respectively, for consistency with the main IR.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70405 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29 20:27:52 +00:00
Dan Gohman
87d2fe5143 Fix a grammaro in a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70331 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-28 21:54:23 +00:00
Nick Lewycky
5cd28fad15 Simplify trunc(extend(x)) in SCEVs, just for completeness. Also fix some odd
whitespace in the same file.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69870 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-23 05:15:08 +00:00
Owen Anderson
03dac74d40 Testcase for PR3909.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69868 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-23 04:33:42 +00:00
Dan Gohman
578ccf81e5 When turning (ashr(shl(x, n), n)) into sext(trunc(x)), the width of the
type to truncate to should be the number of bits of the value that are
preserved, not the number that are clobbered with sign-extension.
This fixes regressions in ldecod.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69704 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-21 20:18:36 +00:00
Chris Lattner
56cb12c9a7 change this to test for an alias result more directly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67046 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-16 18:28:27 +00:00
Nick Lewycky
b24e6c4dd3 Add a replacement for 2009-02-12-GEPNoalias.ll that works without -debug.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67011 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-14 19:40:09 +00:00
Chris Lattner
6dc3a8fd40 remove a buggy test, it is not ok to use -debug in RUN line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66918 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-13 18:19:34 +00:00
Dan Gohman
d4b3a37f96 Update this test for the LoopInfo::print changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65597 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-27 00:17:49 +00:00
Dan Gohman
46bdfb0e6b Rename ScalarEvolution's getIterationCount to getBackedgeTakenCount,
to more accurately describe what it does. Expand its doxygen comment
to describe what the backedge-taken count is and how it differs
from the actual iteration count of the loop. Adjust names and
comments in associated code accordingly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65382 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-24 18:55:53 +00:00
Nick Lewycky
826f7cebfd BasicAA was making the assumption that a local allocation which hadn't escaped
couldn't ever be the return of call instruction. However, it's quite possible
that said local allocation is itself the return of a function call. That's
what malloc and calloc are for, actually.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64442 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-13 07:06:27 +00:00
Owen Anderson
fe9388ccb4 Finish making AliasAnalysis aware of the fact that most atomic intrinsics only dereference their arguments, and enhance
BasicAA to make use of this fact when computing ModRef info.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63718 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-04 05:16:46 +00:00
Nick Lewycky
789558db70 Wind SCEV back in time, to Nov 18th. This 'fixes' PR3275, PR3294, PR3295,
PR3296 and PR3302.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62160 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-13 09:18:58 +00:00
Nick Lewycky
ae285bf5a6 Don't try to analyze this "backward" case. This is overly conservative
pending a correct solution.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61589 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-02 18:54:17 +00:00
Nick Lewycky
3037eda1ef Check that the function prototypes are correct before assuming that the
parameters are pointers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61451 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-27 16:20:53 +00:00
Nick Lewycky
f23d0d392a Resubmit support for the 'nocapture' attribute.
The problematic part of this patch is that we were out of attribute bits,
requiring some fancy bit hacking to make it fit (by shrinking alignment)
without breaking existing users or the file format.

This change will require users to rebuild llvm-gcc to match llvm.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61239 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-19 06:39:12 +00:00
Bill Wendling
43445c153c Remove empty test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61095 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 19:07:17 +00:00
Bill Wendling
6fa311c233 Temporarily revert r61019, r61030, and r61040. These were breaking LLVM Release
builds.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61094 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 19:06:48 +00:00
Nick Lewycky
1447f5ca1f Generalize support for analyzing loops to include SLE/SGE loop exit conditions
and support for non-unit strides with signed exit conditions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61082 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 08:30:01 +00:00
Chris Lattner
1314f20283 Teach basicaa to use the nocapture attribute when possible. When the
intrinsics are properly marked nocapture, the fixme should be addressed.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61040 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 18:59:22 +00:00
Nick Lewycky
8bdc6920cd Revert my re-instated reverted commit, fixes the bootstrap build on x86-64 linux.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60951 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-12 17:09:07 +00:00
Nick Lewycky
277a147f87 Sneaky, sneaky: move the -1 to the outside of the SMax. Reinstate the
optimization of SGE/SLE with unit stride, now that it works properly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60881 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-11 17:40:14 +00:00
Chris Lattner
b957bda0bc Allow basicaa to walk through geps with identical indices in
parallel, allowing it to decide that P/Q must alias if A/B
must alias in things like:
 P = gep A, 0, i, 1
 Q = gep B, 0, i, 1

This allows GVN to delete 62 more instructions out of 403.gcc.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60820 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-10 01:04:47 +00:00