Commit Graph

20 Commits

Author SHA1 Message Date
Jim Grosbach
dbc3577ea1 enable iv-users simplification by default
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89713 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-23 23:25:54 +00:00
Jim Grosbach
97200e4dd4 Teach IVUsers to keep things simpler and track loop-invariant strides only
for uses inside the loop. This works better with LSR. Disabled behind
-simplify-iv-users while benchmarking.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89299 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-19 02:05:44 +00:00
Evan Cheng
586f69a118 - Teach LSR to avoid changing cmp iv stride if it will create an immediate that
cannot be folded into target cmp instruction.
- Avoid a phase ordering issue where early cmp optimization would prevent the
  later count-to-zero optimization.
- Add missing checks which could cause LSR to reuse stride that does not have
  users.
- Fix a bug in count-to-zero optimization code which failed to find the pre-inc
  iv's phi node.
- Remove, tighten, loosen some incorrect checks disable valid transformations.
- Quite a bit of code clean up.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86969 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-12 07:35:05 +00:00
Dan Gohman
a6a4aaefee Fix IVUsers to avoid assuming that the loop has a unique backedge.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86161 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-05 19:41:37 +00:00
Dan Gohman
00cb67359f Instead of testing whether an instruction dominates the loop preheader,
test whether it properly dominates the loop header. This is equivalent
when the loop has a preheader, and has the advantage of working when
the loop doesn't have a preheader. Since IVUsers doesn't Require
LoopSimplify, the loop isn't guaranteed to have a preheader.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82899 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-27 15:30:00 +00:00
Dan Gohman
59faf04a5d Remove a redundant #include.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82897 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-27 15:21:52 +00:00
Chris Lattner
9661c13c37 remove a few dead insertion methods.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79882 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-24 02:39:26 +00:00
Chris Lattner
bbbfa99d3d remove a few DOUTs here and there.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79832 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23 06:35:02 +00:00
Chris Lattner
bdff548e4d eliminate the "Value" printing methods that print to a std::ostream.
This required converting a bunch of stuff off DOUT and other cleanups.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79819 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23 04:37:46 +00:00
Dan Gohman
094ae454e8 Fix more missing newlines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79244 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-17 15:29:31 +00:00
Daniel Dunbar
ce63ffb52f More migration to raw_ostream, the water has dried up around the iostream hole.
- Some clients which used DOUT have moved to DEBUG. We are deprecating the
   "magic" DOUT behavior which avoided calling printing functions when the
   statement was disabled. In addition to being unnecessary magic, it had the
   downside of leaving code in -Asserts builds, and of hiding potentially
   unnecessary computations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77019 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-25 00:23:56 +00:00
Dan Gohman
d9ef1a860e Add a newline, now that Value's operator<< doesn't print one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75568 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-14 00:32:49 +00:00
Dan Gohman
c8d76d5afb Make Loop and MachineLoop be subclasses of LoopBase, rather than typedefs,
using the Curiously Recurring Template Pattern with LoopBase.

This will help further refactoring, and future functionality for
Loop. Also, Headers can now foward-declare Loop, instead of pulling
in LoopInfo.h or doing tricks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75519 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-13 21:51:15 +00:00
Dan Gohman
0bba49cebc Change all SCEV* to SCEV *.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74918 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-07 17:06:11 +00:00
Owen Anderson
372b46cad9 SCEVHandle is no more!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73906 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-22 21:39:50 +00:00
Dan Gohman
958e292c7a Don't (unconditionally) use getSCEVAtScope to simplify the step
expression in IVUsers, because in the case of a use of a non-linear
addrec outside of a loop, this causes the addrec to be evaluated as
a linear addrec.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73774 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-19 17:33:15 +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
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
Duncan Sands
18395d2c3d Avoid getting a compiler warning
IVUsers.cpp: In member function ‘bool llvm::IVUsers::AddUsersIfInteresting(llvm::Instruction*)’:
 IVUsers.cpp:221: warning: ‘isSigned’ may be used uninitialized in this function
with gcc-4.3.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71654 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-13 12:52:44 +00:00
Dan Gohman
81db61a2e6 Factor the code for collecting IV users out of LSR into an IVUsers class,
and generalize it so that it can be used by IndVarSimplify. Implement the
base IndVarSimplify transformation code using IVUsers. This removes
TestOrigIVForWrap and associated code, as ScalarEvolution now has enough
builtin overflow detection and folding logic to handle all the same cases,
and more. Run "opt -iv-users -analyze -disable-output" on your favorite
loop for an example of what IVUsers does.

This lets IndVarSimplify eliminate IV casts and compute trip counts in
more cases. Also, this happens to finally fix the remaining testcases
in PR1301.

Now that IndVarSimplify is being more aggressive, it occasionally runs
into the problem where ScalarEvolutionExpander's code for avoiding
duplicate expansions makes it difficult to ensure that all expanded
instructions dominate all the instructions that will use them. As a
temporary measure, IndVarSimplify now uses a FixUsesBeforeDefs function
to fix up instructions inserted by SCEVExpander. Fortunately, this code
is contained, and can be easily removed once a more comprehensive
solution is available.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71535 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-12 02:17:14 +00:00