Commit Graph

1663 Commits

Author SHA1 Message Date
Devang Patel
25e681ac22 CallGraphSCCPass manager may require other passes.
Use schedulePass() to accomodate these requirement instead of directly
assigning a manager to new CallGraph PassManager.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37695 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-21 22:29:02 +00:00
Dan Gohman
5cec4db6ae Rename ScalarEvolution::deleteInstructionFromRecords to
deleteValueFromRecords and loosen the types to all it to accept
Value* instead of just Instruction*, since this is what
ScalarEvolution uses internally anyway. This allows more flexibility
for future uses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37657 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-19 14:28:31 +00:00
Dan Gohman
f50cd749e1 In SCEVAddExpr::get, skip over any cast operands before looking for nested
add operands after constant operands. The recent change to recognize
sign-extend expressions caused this to be exposed more often.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37628 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-18 19:30:09 +00:00
Anton Korobeynikov
03265f98a3 Make BasicAliasAnalysis correctly register itself. Patch by Devang
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37627 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-18 17:13:29 +00:00
Dan Gohman
0f0eb18add Fold a binary operator with constant operands when expanding code for a SCEV.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37602 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-15 19:21:55 +00:00
Dan Gohman
d19534add9 Add a SCEV class and supporting code for sign-extend expressions.
This created an ambiguity for expandInTy to decide when to use
sign-extension or zero-extension, but it turns out that most of its callers
don't actually need a type conversion, now that LLVM types don't have
explicit signedness. Drop expandInTy in favor of plain expand, and change
the few places that actually need a type conversion to do it themselves.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37591 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-15 14:38:12 +00:00
Devang Patel
4d42dea253 Break DominatorTree from ETNode.
Remove unused PostETForest.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37551 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-12 00:54:38 +00:00
Devang Patel
53c279b194 Use DominatorTree instead of ETForest.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37507 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-08 00:17:13 +00:00
Devang Patel
6ea7ac6a1e Use DominatorTree instead of ETForest.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37505 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-07 23:53:38 +00:00
Devang Patel
9a51157db5 Maintain ETNode as part of DomTreeNode.
This adds redundancy for now.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37492 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-07 17:47:21 +00:00
Nick Lewycky
51e844b601 Optimize this test. Firstly, only Instructions may use other Instructions.
Secondly, checking whether removal succeeded tells you whether it was in
the map to begin with.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37469 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-06 11:26:20 +00:00
Nick Lewycky
9d0332f7b4 Fix PR1487 and Transforms/IndVar/2007-06-06-DeleteDanglesPtr.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37459 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-06 04:12:20 +00:00
Devang Patel
a301a16841 Fix PR 1497
Use separate pass id for CFGOnlyPrinter.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37439 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-05 20:24:36 +00:00
Devang Patel
26042420d6 s/llvm::DominatorTreeBase::DomTreeNode/llvm::DomTreeNode/g
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37407 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-04 00:32:22 +00:00
Devang Patel
bec7647f98 s/DominatorTreeBase::Node/DominatorTreeBase:DomTreeNode/g
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37403 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-03 06:26:14 +00:00
Chris Lattner
f711fb7af8 when merging two alias sets together, be sure to propagate the volatility of
the inner set.  This fixes PR1435 and Transforms/LICM/2007-05-22-VolatileSink.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37305 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-23 06:36:35 +00:00
Dan Gohman
a196b993e0 Add passes -view-cfg and -view-cfg-only that are like -print-cfg and
-print-cfg-only except they use the ViewCFG function, which displays the
CFG rendered with graphviz with gv.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37033 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-14 14:25:08 +00:00
Nick Lewycky
ecd94c804a Fix typo in comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36873 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-06 13:37:16 +00:00
Devang Patel
1997473cf7 Drop 'const'
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36662 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-03 01:11:54 +00:00
Devang Patel
3e15bf33e0 Use 'static const char' instead of 'static const int'.
Due to darwin gcc bug, one version of darwin linker coalesces
static const int, which defauts PassID based pass identification.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36652 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-02 21:39:20 +00:00
Lauro Ramos Venancio
c718288f49 Fix build error.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36648 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-02 20:37:47 +00:00
Devang Patel
794fd75c67 Do not use typeinfo to identify pass in pass manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36632 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-01 21:15:47 +00:00
Zhou Sheng
843f0767ac Make use of ConstantInt::isZero instead of ConstantInt::isNullValue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36261 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-19 05:39:12 +00:00
Devang Patel
5a713cc72f Cache DT[*SI] lookup.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36239 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-18 01:19:55 +00:00
Devang Patel
7cc6dcf6e0 Fix
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070416/047971.html


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36236 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-18 00:53:01 +00:00
Chris Lattner
b1b2f0bc44 Be more careful when inserting reused instructions. This fixes CodeGen/Generic/2007-04-17-lsr-crash.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36231 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-17 23:43:50 +00:00
Chris Lattner
8e8f865227 Remove use of Instruction::getNext
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36201 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-17 17:52:45 +00:00
Anton Korobeynikov
bed2946a96 Removed tabs everywhere except autogenerated & external files. Add make
target for tabs checking.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36146 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-16 18:10:23 +00:00
Reid Spencer
3e35c8d15e Revert last patch. It was already fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36102 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-16 02:24:41 +00:00
Reid Spencer
b4a7fea7fd For PR1336:
Fix a div-by-zero bug noticed by APInt. This fixes:
test/Transforms/IndVarsSimplify/exit_value_tests.llx


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36099 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-16 01:48:37 +00:00
Owen Anderson
e934fefd6b Tabs -> Spaces
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36094 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-15 23:14:18 +00:00
Chris Lattner
fe560b8c85 Fix a nasty bug introduced when apint'ified. This fixes
Transforms/IndVarsSimplify/exit_value_tests.llx


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36081 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-15 19:52:49 +00:00
Owen Anderson
3dc6776b33 Remove ImmediateDominator analysis. The same information can be obtained from DomTree. A lot of code for
constructing ImmediateDominator is now folded into DomTree construction.

This is part of the ongoing work for PR217.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36063 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-15 08:47:27 +00:00
Chris Lattner
7fec90ebf4 CSE simple binary expressions when they are inserted. This makes LSR produce
less huge code that needs to be cleaned up by sdisel.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35959 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-13 05:04:18 +00:00
Zhou Sheng
414de4df41 Eliminate unnecessary APInt construction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35740 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-07 17:48:27 +00:00
Zhou Sheng
fdc1e16dcf Make APInt variables do the computation stuffs instead of
ConstantExpr::getXX if possible.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35738 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-07 17:40:57 +00:00
Zhou Sheng
8342836d70 Eliminate unnecessary zext/trunc stuffs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35737 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-07 17:12:38 +00:00
Owen Anderson
ba43963e96 Completely purge DomSet. This is the (hopefully) final patch for PR1171.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35731 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-07 07:17:27 +00:00
Owen Anderson
46b58f7869 Expunge DomSet from LoadValueNumbering. This is part of the continuing
work on PR1171.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35723 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-07 04:43:07 +00:00
Chris Lattner
2811f2a670 Treat xor of signbit like an add.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35586 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-02 05:41:38 +00:00
Reid Spencer
e613555fd9 The bit counting intrinsics return i32 not the operand type. This fixes
last night's regression in SingleSource/UnitTests/2005-05-11-Popcount-ffs-fls


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35556 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-01 18:42:20 +00:00
Reid Spencer
e9391fd9b5 For PR1297:
Support overloaded intrinsics bswap, ctpop, cttz, ctlz.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35547 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-01 07:35:23 +00:00
Dan Gohman
ecb7a77885 Change uses of Function::front to Function::getEntryBlock for readability.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35265 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-22 16:38:57 +00:00
Devang Patel
5ee9997906 Now IndVarSimplify is a LoopPass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35003 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-07 06:39:01 +00:00
Devang Patel
1bc89361c2 Now LoopUnswitch is a LoopPass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34992 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-07 00:26:10 +00:00
Devang Patel
622adea47f Insert loop into LQ before visiting children.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34982 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-06 19:50:49 +00:00
Devang Patel
c37177eb72 Use schedulePass() instead of assignPassManager() to add new LPPassManager.
This ensures that require analysis info is available.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34980 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-06 19:11:25 +00:00
Devang Patel
a885c06bdf Add LPPassManager::insertLoop().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34979 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-06 19:00:02 +00:00
Devang Patel
7a9a0695f2 LPPassManager::deleteLoopFromQueue() add meat. Cut-n-paste code from
LoopUnswitch pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34977 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-06 18:38:33 +00:00
Devang Patel
22033be445 LPPassManager. Implement preparePassManager() hook.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34975 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-06 17:59:37 +00:00
Devang Patel
a5057d02c0 LPPassManager : Add initialization and finalizatino hooks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34968 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-06 16:59:03 +00:00
Devang Patel
30159729ad Use std::deque to manage loop queue inside LPPassManager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34943 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-06 02:30:46 +00:00
Devang Patel
7f99761143 Avoid constructing std::strings unless pass debugging is ON.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34933 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-05 20:01:30 +00:00
Jeff Cohen
ca5183d445 Unbreak VC++ build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34917 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-05 00:00:42 +00:00
Chris Lattner
b1f5d8bf6f Speed up Loop::isLCSSAForm by using a hash table instead of a sorted vector.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34900 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-04 04:06:39 +00:00
Reid Spencer
0797605204 Guard further against APInt operations with operands of unequal bit width.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34897 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-04 01:25:35 +00:00
Reid Spencer
9b4aeb3cc1 Fix an unequal bitwidth issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34831 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-02 02:59:25 +00:00
Reid Spencer
cae5754619 Prefer non-virtual calls to ConstantInt::isZero over virtual calls to
Constant::isNullValue() in situations where it is possible.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34821 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-02 00:28:52 +00:00
Reid Spencer
35fa43907e Make it possible to create an SCEVUnknown from an APInt as well as an int.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34816 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-01 22:28:51 +00:00
Reid Spencer
4d050d7321 Avoid a potential assert out if the loop increment is > 64 bits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34798 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-01 19:45:00 +00:00
Reid Spencer
c7cd7a0bb1 Construct ConstantInt with simpler constructor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34795 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-01 19:32:33 +00:00
Reid Spencer
e479ef0b41 Fix last night's 445.gobmk breakage which was caused by comparison of
APInt's of unequal bitwidth.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34790 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-01 17:17:21 +00:00
Reid Spencer
a6e8a955d6 Remove the "isSigned" parameters from ConstantRange. It turns out they
are not needed as the results are the same with or without it.

Patch by Nicholas Lewycky.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34782 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-01 07:54:15 +00:00
Reid Spencer
e8019bb1fc APIntify various computations in ScalarEvolution
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34780 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-01 07:25:48 +00:00
Reid Spencer
6263cbada2 For PR1205:
Make GetConstantFactor compute its result using an APInt.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34765 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-28 23:31:17 +00:00
Reid Spencer
c6aedf70b3 For PR1205:
Adjust to changes in ConstantRange interface.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34762 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-28 22:03:51 +00:00
Reid Spencer
bb626a6751 Move ConstantRange class to lib/Support from lib/Analysis and make its
interface not depend on Type or ICmpInst.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34761 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-28 22:02:48 +00:00
Reid Spencer
581b0d453a For PR1205:
Remove ConstantInt from ConstantRange interface and adjust its users to
compensate.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34758 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-28 19:57:34 +00:00
Reid Spencer
dc5c159701 For PR1205:
First round of ConstantRange changes. This makes all CR constructors use
only APInt and not use ConstantInt. Clients are adjusted accordingly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34756 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-28 18:57:32 +00:00
Reid Spencer
663e711dc2 For PR1205:
Convert ConstantRange class to use APInt internally as its value type for
the constant range, instead of ConstantInt.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34745 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-28 17:36:23 +00:00
Devang Patel
84da80d10b Make getPassManagerType() const.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34669 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-27 15:00:39 +00:00
Devang Patel
5b9e8d6aab Fix thinko.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34528 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-23 18:05:55 +00:00
Devang Patel
4b2646326b Loop passes are set up to accept pointer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34527 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-23 17:53:17 +00:00
Devang Patel
bfd5905584 Teach LoopPass to assign itself one Loop Pass Manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34510 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-23 00:36:57 +00:00
Devang Patel
8ded5852fe Add facility that allows LoopPass to re-insert a loop into
Loop Pass Manager's queue.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34509 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-23 00:16:44 +00:00
Devang Patel
5afdc7d785 Add LPPassManager interface that LoopPass can use to skip
rest of the passes in the queue for a loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34508 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-23 00:10:16 +00:00
Devang Patel
643a79b4b3 Populate and walk loop queue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34505 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-22 23:45:15 +00:00
Devang Patel
d0e6e33043 Add LoopQueue. This is used by loop pass manager to manage loop nest.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34504 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-22 23:30:07 +00:00
Devang Patel
16a31c4ebf Add Loop Pass Manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34487 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-22 08:56:17 +00:00
Reid Spencer
9d6565a5b1 For PR1195:
Rename PackedType -> VectorType, ConstantPacked -> ConstantVector, and
PackedTyID -> VectorTyID. No functional changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34293 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-15 02:26:10 +00:00
Nick Lewycky
3e051647c0 Fix comments to match names of functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34173 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-11 00:58:49 +00:00
Chris Lattner
a77600e861 Switch some std::vector's to SmallVectors. This speeds up -load-vn -gcse
by 6% on tramp3d.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34167 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-10 22:15:31 +00:00
Chris Lattner
fd1ad3b730 modify CheckGEPInstructions to take a pointer and size instead of a vector.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34166 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-10 22:12:53 +00:00
Chris Lattner
829621c59e eliminate use of TargetData::getIndexedOffset that takes a vector
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34163 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-10 20:35:22 +00:00
Chris Lattner
309f87e34a completely eliminate a temporary vector
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34162 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-10 20:33:15 +00:00
Chris Lattner
b1919e2f08 Privatize StructLayout::MemberOffsets, adding an accessor
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34156 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-10 19:55:17 +00:00
Reid Spencer
d7d83db5f2 Make classes in anonymous namespaces use VISIBILITY_HIDDEN to help reduce
LLVM's footprint and speed up linking.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33941 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-05 23:42:17 +00:00
Reid Spencer
832254e1c2 Changes to support making the shift instructions be true BinaryOperators.
This feature is needed in order to support shifts of more than 255 bits
on large integer types.  This changes the syntax for llvm assembly to
make shl, ashr and lshr instructions look like a binary operator:
   shl i32 %X, 1
instead of
   shl i32 %X, i8 1
Additionally, this should help a few passes perform additional optimizations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33776 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-02 02:16:23 +00:00
Devang Patel
95ced11b1a Dump function names when debug-pass=Executions is used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33772 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-01 22:38:33 +00:00
Devang Patel
505f36aede Pretty print pass manager
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33766 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-01 22:09:37 +00:00
Chris Lattner
ad58eb3434 Fix a minor bug in my patch yesterday that broken ConstProp/bswap.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33704 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-31 18:04:55 +00:00
Chris Lattner
d917fe5692 elimiante a temporary vector
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33694 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-31 04:42:05 +00:00
Chris Lattner
03dd25ca96 Move some symbolic constant folding code out of instcombine into a place
it can be used by multiple clients.  This specifically allows the inliner
to constant fold symbolically.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33687 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-31 00:51:48 +00:00
Chris Lattner
2e3a1d137c The local "ConstantFold" method is now just a watered down version of
ConstantFoldInstOperands.  Switch to ConstantFoldInstOperands and remove
ConstantFold.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33683 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-30 23:52:44 +00:00
Chris Lattner
5520732b24 move a bunch of constant folding code f rom Transforms/Utils/Local.cpp into
libanalysis/ConstantFolding.cpp.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33679 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-30 23:45:45 +00:00
Chris Lattner
72d88ae544 adjust to constant folding api changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33673 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-30 23:15:43 +00:00
Reid Spencer
5cbf985dcb For PR1136: Rename GlobalVariable::isExternal as isDeclaration to avoid
confusion with external linkage types.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33663 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-30 20:08:39 +00:00
Devang Patel
f5b17fd938 Use StartPassTimer() and StopPassManager()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33640 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-29 23:29:54 +00:00
Devang Patel
f82aa1cf73 Measure timings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33627 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-29 20:08:03 +00:00
Devang Patel
129ccd9def Remove dead code.
CallGraphSCCPass does not need to implement runOnModule().
It supports runOnSCC().


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33516 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-26 01:08:18 +00:00
Devang Patel
d9f10c3d11 Fix typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33467 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-23 21:55:17 +00:00
Devang Patel
97fd2439f2 Add CallGraphSCCPass::assignPassManager().
This enables CalLGraphPassManager.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33466 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-23 21:52:35 +00:00
Reid Spencer
24d6da5fed For PR970:
Clean up handling of isFloatingPoint() and dealing with PackedType.
Patch by Gordon Henriksen!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33415 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-21 00:29:26 +00:00
Reid Spencer
c10305743c For PR1043:
This is the final patch for this PR. It implements some minor cleanup
in the use of IntegerType, to wit:
1. Type::getIntegerTypeMask -> IntegerType::getBitMask
2. Type::Int*Ty changed to IntegerType* from Type*
3. ConstantInt::getType() returns IntegerType* now, not Type*

This also fixes PR1120.

Patch by Sheng Zhou.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33370 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-19 21:13:56 +00:00
Devang Patel
75f9abf517 Add CGPassManager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33309 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-17 21:45:01 +00:00
Jeff Cohen
1b30754ba9 Unbreak VC++ build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33242 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-15 20:27:18 +00:00
Chris Lattner
b5282dcf47 Constant fold llvm.powi.*. This speeds up tramp3d--v4 by 9.5%
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33229 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-15 06:27:37 +00:00
Chris Lattner
42a7551725 rename Type::isIntegral to Type::isInteger, eliminating the old Type::isInteger.
rename Type::getIntegralTypeMask to Type::getIntegerTypeMask.

This makes naming much more consistent.  For example, there are now no longer any
instances of IntegerType that are not considered isInteger! :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33225 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-15 02:27:26 +00:00
Chris Lattner
b2f3e703bc Update code to eliminate calls to isInteger, calling isIntegral instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33220 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-15 01:58:56 +00:00
Chris Lattner
0762705087 Fix correlated exprs regressions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33214 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-15 01:02:34 +00:00
Chris Lattner
241607d016 fit to 80 cols.
Remove now-extraneous checks for ptr->ptr bitcasts.

Fix PR1109 and Analysis/BasicAA/2007-01-13-BasePointerBadNoAlias.ll.  We
need to consider arbitrary sized objects when checking for nested GEP offsets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33195 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-14 05:57:53 +00:00
Chris Lattner
192e403744 Fix PR1101 and Analysis/ScalarEvolution/trip-count.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33193 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-14 01:24:47 +00:00
Chris Lattner
ef3baf0979 don't discriminate against bool
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33128 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-12 18:28:58 +00:00
Chris Lattner
05b30d840a remove unneeded special cases
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33127 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-12 18:23:49 +00:00
Chris Lattner
0bb38313ae GEP operands can't be bools
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33125 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-12 18:20:48 +00:00
Reid Spencer
579dca12c2 Implement review feedback for the ConstantBool->ConstantInt merge. Chris
recommended that getBoolValue be replaced with getZExtValue and that
get(bool) be replaced by get(const Type*, uint64_t). This implements
those changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33110 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-12 04:24:46 +00:00
Reid Spencer
4fe16d607d Rename BoolTy as Int1Ty. Patch by Sheng Zhou.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33076 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-11 18:21:29 +00:00
Zhou Sheng
6b6b6ef167 For PR1043:
Merge ConstantIntegral and ConstantBool into ConstantInt.
Remove ConstantIntegral and ConstantBool from LLVM.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33073 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-11 12:24:14 +00:00
Reid Spencer
ca7ad8942a Fix a bug in an assert that would never trigger.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33005 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-08 05:34:39 +00:00
Reid Spencer
e7ca042730 Convert uses of getPrimitiveSize that should be getPrimitiveSizeInBits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33003 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-08 01:26:33 +00:00
Chris Lattner
257cbf7a8d remove llvm.isunordered
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32991 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-07 08:19:47 +00:00
Chris Lattner
8b0e3602e2 Fix PR1015 and Transforms/IndVarsSimplify/2007-01-06-TripCount.ll, a
miscompilation of Qt.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32974 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-07 02:24:26 +00:00
Chris Lattner
f82188c9ce cast of int to bool no longer does a compare, rendering this fixme
obsolete


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32972 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-07 02:05:20 +00:00
Reid Spencer
c5b206b6be For PR950:
This patch replaces signed integer types with signless ones:
1. [US]Byte -> Int8
2. [U]Short -> Int16
3. [U]Int   -> Int32
4. [U]Long  -> Int64.
5. Removal of isSigned, isUnsigned, getSignedVersion, getUnsignedVersion
   and other methods related to signedness. In a few places this warranted
   identifying the signedness information from other sources.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32785 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-31 05:48:39 +00:00
Reid Spencer
e4d87aa2de For PR950:
This patch removes the SetCC instructions and replaces them with the ICmp
and FCmp instructions. The SetCondInst instruction has been removed and
been replaced with ICmpInst and FCmpInst.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32751 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-23 06:05:41 +00:00
Reid Spencer
d377350718 Add a FIXME about signedness.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32732 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-21 18:59:16 +00:00
Reid Spencer
2e20d39493 Add some comments about things that can go away once signless types are in.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32727 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-21 06:43:46 +00:00
Chris Lattner
3b27d68c6a eliminate static ctors from Statistics
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32697 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-19 22:30:33 +00:00
Chris Lattner
75de5ab9f5 Fix a bug in GetConstantFactor for affine expressions, in which the existing
code was wrong for things like 3+4*i.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32662 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-19 01:16:02 +00:00
Bill Wendling
5c7e326585 Added an automatic cast to "std::ostream*" etc. from OStream. We then can
rework the hacks that had us passing OStream in. We pass in std::ostream*
instead, check for null, and then dispatch to the correct print() method.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32636 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-17 05:15:13 +00:00
John Criswell
d943acae16 Changed from PARALLEL_DIRS to DIRS since we're only building one directory.
Thanks Reid.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32551 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-13 19:42:54 +00:00
John Criswell
2957f129a7 Remove DSA.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32550 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-13 19:41:57 +00:00
John Criswell
e026c070c4 Remove DSA.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32542 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-13 16:54:24 +00:00
Reid Spencer
3ba68b9eef Change the interface to SCEVExpander::InsertCastOfTo to take a cast opcode
so the decision of which opcode to use is pushed upward to the caller.
Adjust the callers to pass the expected opcode.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32535 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-13 08:06:42 +00:00
Reid Spencer
d977d8651a Replace inferred getCast(V,Ty) calls with more strict variants.
Rename getZeroExtend and getSignExtend to getZExt and getSExt to match
the the casting mnemonics in the rest of LLVM.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32514 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-12 23:36:14 +00:00
Reid Spencer
b6ba3e6d85 Get even more accurate on the casting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32478 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-12 09:17:50 +00:00
Reid Spencer
4da49122f3 Change inferred getCast into specific getCast. Passes all tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32469 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-12 05:05:00 +00:00
Chris Lattner
a17f03980f teach scev to analyze X*4|1 like X*4+c. This allows us to produce:
LBB1_1: #bb
        movdqa (%esi), %xmm2
        movaps %xmm2, %xmm3
        punpcklbw %xmm0, %xmm3
        movaps %xmm3, %xmm4
        punpcklwd %xmm0, %xmm4
        cvtdq2ps %xmm4, %xmm4
        mulps %xmm1, %xmm4
        movaps %xmm4, (%edi)
        leal 1(,%eax,4), %ebx
        shll $4, %ebx
        punpckhwd %xmm0, %xmm3
        cvtdq2ps %xmm3, %xmm3
        mulps %xmm1, %xmm3
        movaps %xmm3, (%edx,%ebx)
        leal 2(,%eax,4), %ebx
        shll $4, %ebx
        punpckhbw %xmm0, %xmm2
        movaps %xmm2, %xmm3
        punpcklwd %xmm0, %xmm3
        cvtdq2ps %xmm3, %xmm3
        mulps %xmm1, %xmm3
        movaps %xmm3, (%edx,%ebx)
        leal 3(,%eax,4), %ebx
        shll $4, %ebx
        punpckhwd %xmm0, %xmm2
        cvtdq2ps %xmm2, %xmm2
        mulps %xmm1, %xmm2
        movaps %xmm2, (%edx,%ebx)
        addl $64, %edi
        incl %eax
        addl $16, %esi
        cmpl %ecx, %eax
        jne LBB1_1      #bb

instead of:

LBB1_1: #bb
        movdqa (%esi), %xmm2
        movaps %xmm2, %xmm3
        punpcklbw %xmm0, %xmm3
        movaps %xmm3, %xmm4
        punpcklwd %xmm0, %xmm4
        cvtdq2ps %xmm4, %xmm4
        mulps %xmm1, %xmm4
        movaps %xmm4, (%edi)
        leal 1(,%eax,4), %ebx
        shll $4, %ebx
        punpckhwd %xmm0, %xmm3
        cvtdq2ps %xmm3, %xmm3
        mulps %xmm1, %xmm3
        movaps %xmm3, (%edx,%ebx)
        leal 2(,%eax,4), %ebx
        shll $4, %ebx
        punpckhbw %xmm0, %xmm2
        movaps %xmm2, %xmm3
        punpcklwd %xmm0, %xmm3
        cvtdq2ps %xmm3, %xmm3
        mulps %xmm1, %xmm3
        movaps %xmm3, (%edx,%ebx)
        leal 3(,%eax,4), %ebx
        shll $4, %ebx
        punpckhwd %xmm0, %xmm2
        cvtdq2ps %xmm2, %xmm2
        mulps %xmm1, %xmm2
        movaps %xmm2, (%edx,%ebx)
        addl $64, %edi
        incl %eax
        addl $16, %esi
        cmpl %ecx, %eax
        jne LBB1_1      #bb

for a testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32463 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-12 02:26:09 +00:00
Chris Lattner
82e8a8ffe4 clarify some comments, simplify some checks, fix:
Regression/Transforms/IndVarsSimplify/2006-12-10-BitCast.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32420 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-11 00:12:31 +00:00
Bill Wendling
bcd2498f4f Removed more <iostream> includes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32321 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-07 20:28:15 +00:00
Bill Wendling
e81561909d Changed llvm_ostream et all to OStream. llvm_cerr, llvm_cout, llvm_null, are
now cerr, cout, and NullStream resp.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32298 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-07 01:30:32 +00:00
Reid Spencer
c6bf4bfc35 Adjust to new ConstantIntegral interface for Max/Min tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32289 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-06 20:45:15 +00:00
Chris Lattner
ac0b6ae358 Detemplatize the Statistic class. The only type it is instantiated with
is 'unsigned'.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32279 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-06 17:46:33 +00:00
Chris Lattner
e53883837d Simplify code
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32270 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-06 06:35:25 +00:00
Chris Lattner
3749c9cae4 Remove the 'printname' argument to WriteAsOperand. It is always true, and
passing false would make the asmprinter fail anyway.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32264 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-06 06:16:21 +00:00
Reid Spencer
315d05542c Finally get the casting right in this file. Also, remove some unnecessary
casting because sdiv doesn't require operand signs to match any more.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32240 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-05 22:39:58 +00:00
Chris Lattner
f2d9ceb5b9 straighten out various memory ownership issues in the callgraph stuff.
This fixes Regression/Other/2002-01-31-CallGraph.ll.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32237 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-05 19:46:12 +00:00
Reid Spencer
7858b336f2 Bail on the getInferredCast idea. Remove the function and convert
remaining uses to more specific casts.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32231 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-05 19:14:13 +00:00
Reid Spencer
09906f3e1a Fix comment grammaro
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32198 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-04 21:33:23 +00:00
Chris Lattner
12d38bfca0 Add a comment and fix a memory leak. Thanks to Vikram for pointing this out.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32196 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-04 21:22:45 +00:00