Commit Graph

1861 Commits

Author SHA1 Message Date
Dan Gohman
a60832b018 Fix a bogus srem rule - a negative value srem'd by a power-of-2
can have a non-negative result; for example, -16%16 is 0. Also,
clarify the related comments. This fixes PR2670.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54767 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-13 23:12:35 +00:00
Duncan Sands
81b06be055 Teach constant folding that an inttoptr of a
ptrtoint can be turned into a bitcast if the
integer is at least as wide as a pointer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54752 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-13 20:20:35 +00:00
Dan Gohman
3837218ea0 Extend ScalarEvolution's executesAtLeastOnce logic to be able to
continue past the first conditional branch when looking for a
relevant test. This helps it avoid using MAX expressions in
loop trip counts in more cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54697 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-12 20:17:31 +00:00
Chris Lattner
afcde473c5 "This patch adds a virtual call to AbstractLatticeFunction to derive a
type lattice value for an Argument*, giving clients the opportunity to
use something other than Top for it if they choose to."

Patch by John McCall!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54589 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-09 17:23:35 +00:00
Dan Gohman
d9cc749318 Canonicalize nested AddRecs in by nesting them in order of loop depth.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54545 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-08 18:33:12 +00:00
Chris Lattner
0dabb7e8f3 Don't call getAnalysisUsage unless -debug-pass is enabled. This speeds
up the passmgr by avoiding useless work.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54528 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-08 15:14:09 +00:00
Eli Friedman
b42a626122 PR2621: Improvements to the SCEV AddRec binomial expansion. This
version uses a new algorithm for evaluating the binomial coefficients 
which is significantly more efficient for AddRecs of more than 2 terms 
(see the comments in the code for details on how the algorithm works).  
It also fixes some bugs: it removes the arbitrary length restriction for 
AddRecs, it fixes the silent generation of incorrect code for AddRecs 
which require a wide calculation width, and it fixes an issue where we 
were incorrectly truncating the iteration count too far when evaluating 
an AddRec expression narrower than the induction variable.

There are still a few related issues I know of: I think there's 
still an issue with the SCEVExpander expansion of AddRec in terms of
the width of the induction variable used.  The hack to avoid generating 
too-wide integers shouldn't be necessary; instead, the callers should be 
considering the cost of the expansion before expanding it (in addition 
to not expanding too-wide integers, we might not want to expand 
expressions that are really expensive, especially when optimizing for 
size; calculating an length-17 32-bit AddRec currently generates about 250 
instructions of straight-line code on X86).  Also, for long 32-bit 
AddRecs on X86, CodeGen really sucks at scheduling the code.  I'm planning on 
filing follow-up PRs for these issues.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54332 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-04 23:49:06 +00:00
Eli Friedman
1fbffe0cef Another SCEV issue from PR2607; essentially the same issue, but this
time applying to the implicit comparison in smin expressions. The 
correct way to transform an inequality into the opposite 
inequality, either signed or unsigned, is with a not expression.

I looked through the SCEV code, and I don't think there are any more 
occurrences of this issue.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54194 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-30 04:36:32 +00:00
Eli Friedman
068acc3caa Fix for PR2607: SCEV miscomputing the loop count for loops with an
SGT exit condition.  Essentially, the correct way to flip an inequality 
in 2's complement is the not operator, not the negation operator.  
That said, the difference only affects cases involving INT_MIN.

Also, enhance the pre-test search logic to be a bit smarter about 
inequalities flipped with a not operator, so it can eliminate the smax 
from the iteration count for simple loops.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54184 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-30 00:04:08 +00:00
Owen Anderson
d4310a5d41 Fix a subtle bug when removing instructions from memdep. In very specific
circumstances we could end up remapping a dependee to the same instruction 
that we're trying to remove.  Handle this properly by just falling back to
a conservative solution.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54132 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-28 16:00:58 +00:00
Nate Begeman
b5557abcf1 Fix minor issues with VICmp/VFCmp constant expressions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54030 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-25 17:35:37 +00:00
Nick Lewycky
9e13cbc171 Revert r53812 -- premature. LegalizeTypes isn't actually on yet!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53816 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-21 04:03:00 +00:00
Nick Lewycky
2ceb40f3da Switch on the use of arbitrary precision integers in scalar evolution. This will
bail after 256-bits to avoid producing code that the backends can't handle.
Previously, we capped it at 64-bits, preferring to miscompile in those cases.

This change also reverts much of r52248 because the invariants the code was
expecting are now being met.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53812 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-21 02:51:31 +00:00
Wojciech Matyjewicz
8b82c49084 This header isn't necessary now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53811 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-20 17:35:32 +00:00
Wojciech Matyjewicz
de0f2382e4 Fix PR2088. Use modulo linear equation solver to compute loop iteration
count.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53810 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-20 15:55:14 +00:00
Matthijs Kooijman
dddc827125 Don't use ++idx_begin when I actually mean idx_begin + 1, especially since we
also use *idx_begin in the same expression, giving unpredictable results.

This fixes this bug: http://lists.cs.uiuc.edu/pipermail/llvmdev/2008-July/015877.html



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53670 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-16 10:47:35 +00:00
Nick Lewycky
8ae38e1516 Correct this inversion!
I swear that didn't show up in svn diff...


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53587 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-15 03:47:44 +00:00
Nick Lewycky
86dae65baa Fix up comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53586 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-15 03:40:27 +00:00
Nick Lewycky
59cff12f88 Stop creating extraneous smax/umax in SCEV. This removes a regression where we
started complicating many loops ('for' loops, in fact).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53508 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-12 07:41:32 +00:00
Dan Gohman
e6acf36dca Fix spelling of "hierarchy" in comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53489 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-11 22:51:32 +00:00
Dan Gohman
c418bf3dd5 Use find instead of lower_bound.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53474 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-11 20:58:19 +00:00
Nick Lewycky
b0b046848f Remove getValueRange from SCEV. It wasn't doing anything there anyways, and a
more complete version is now available from the LoopVR pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53269 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-09 03:21:51 +00:00
Nick Lewycky
6177fd4fce Expand SCEVUDiv of power of 2 to a lshr instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53217 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-08 05:05:37 +00:00
Nick Lewycky
01eaf803ca Handle 'lshr' instruction with SCEVUDiv object.
Comment the xor %x, -1 case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53167 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-07 06:15:49 +00:00
Devang Patel
70c09c54b1 Keep track of inherited analysis (e.g. dominator tree).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53088 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-03 07:02:30 +00:00
Owen Anderson
f2aa160b35 A better fix for PR2503 that doesn't pessimize GVN in the presence of unreachable blocks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53032 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-02 17:20:16 +00:00
Devang Patel
844a3d163b Fix typos in comments.
Thanks for the feedback!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52978 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-01 19:50:56 +00:00
Devang Patel
5b57e720c8 Add dom info verifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52967 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-01 17:44:24 +00:00
Owen Anderson
c4b871c650 Properly handle cases where a predecessor of the block being queried on is unreachable.
This fixes PR2503, though we should also fix other passes not to emit this kind of code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52946 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-01 00:40:58 +00:00
Evan Cheng
0ff39b3feb - Re-apply 52748 and friends with fix. GetConstantStringInfo() returns an empty string for ConstantAggregateZero case which surprises selectiondag.
- Correctly handle memcpy from constant string which is zero-initialized.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52891 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-30 07:31:25 +00:00
Nick Lewycky
a11e2eb845 Add a value range analysis that lazily computes ranges using ScalarEvolutions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52885 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-30 00:04:21 +00:00
Anton Korobeynikov
6d116bc7ce Revert (52748 and friends):
Move GetConstantStringInfo to lib/Analysis. Remove
string output routine from Constant. Update all
callers. Change debug intrinsic api slightly to
accomodate move of routine, these now return values
instead of strings.

This unbreaks llvm-gcc bootstrap.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52884 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-29 17:57:03 +00:00
Chris Lattner
b746b82113 Add back the capability to include nul characters in strings with
GetConstantStringInfo.  This will hopefully restore llvm-gcc to 
happy bootstrap land.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52851 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-28 05:33:32 +00:00
Chris Lattner
3284d42c17 Tighten up checking.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52850 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-28 04:37:04 +00:00
Chris Lattner
3648f9f0ae fix the regressions from Eric's patch by making GetConstantStringInfo
tolerate a non-nul-terminated string, and handling a direct global 
reference.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52813 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-27 03:36:51 +00:00
Owen Anderson
aefacb5972 Reserve the size we'll need in advance.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52763 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-26 04:47:41 +00:00
Eric Christopher
0d2b0aba42 Move GetConstantStringInfo to lib/Analysis. Remove
string output routine from Constant. Update all
callers. Change debug intrinsic api slightly to
accomodate move of routine, these now return values
instead of strings.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52748 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-26 00:31:12 +00:00
Dan Gohman
6c459a28ec Generalize createSCEV to be able to form SCEV expressions from
ConstantExprs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52615 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-22 19:56:46 +00:00
Dan Gohman
17f1972c77 Use SCEVAddRecExpr::isAffine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52614 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-22 19:23:09 +00:00
Dan Gohman
11f6d3b478 Move a few more SCEVExpander methods out-of-line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52612 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-22 19:09:18 +00:00
Chris Lattner
9d2c9bd113 fix warning when assertions disabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52589 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-21 19:48:22 +00:00
Duncan Sands
9954c76f2c Fix some warnings reported by gcc-4.3. Hopefully
this still compiles on windows - I can't test!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52488 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-19 08:47:31 +00:00
Dan Gohman
e24fa64d52 Move SCEVExpander::visitAddExpr out-of-line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52464 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-18 16:37:11 +00:00
Dan Gohman
cfeb6a4506 Move LSR's private isZero function to a public SCEV member
function, and make use of it in several places.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52463 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-18 16:23:07 +00:00
Matthijs Kooijman
3faf9df08f Use a SmallVector instead of an array, since auto_ptr doesn't handle arrays
properly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52390 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-17 08:24:37 +00:00
Matthijs Kooijman
0a9aaf46be Make BuildSubAggregate use FindInsertedElement again to prevent it from
inserting extractvalues. In particular, this prevents the insertion of
extractvalues that can't be folded away later. Also add an example of when this
stuff is needed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52328 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16 14:13:46 +00:00
Matthijs Kooijman
9772891219 Make the InsertBefore argument to FindInsertedValue optional, so you can find an inserted value without modifying the code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52319 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16 13:28:31 +00:00
Matthijs Kooijman
0a7413dad8 Pass around Instruction* instead of Instruction& in FindInsertedValue and friends.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52318 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16 13:13:08 +00:00
Matthijs Kooijman
710eb236e6 80 column fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52316 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16 12:57:37 +00:00
Matthijs Kooijman
b23d5adbc8 Move FindScalarValue from InstructionCombining.cpp to ValueTracking.cpp. While
I'm at it, rename it to FindInsertedValue.

The only functional change is that newly created instructions are no longer
added to instcombine's worklist, but that is not really necessary anyway (and
I'll commit some improvements next that will completely remove the need).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52315 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16 12:48:21 +00:00