Commit Graph

75 Commits

Author SHA1 Message Date
Bob Wilson f1aa4743d9 Revert all my SSAUpdater patches. The PHI placement algorithm is not correct
(what was I thinking?) and there's also a problem with LCSSA.  I'll try again
later with fixes.

--- Reverse-merging r100263 into '.':
U    lib/Transforms/Utils/SSAUpdater.cpp
--- Reverse-merging r100177 into '.':
G    lib/Transforms/Utils/SSAUpdater.cpp
--- Reverse-merging r100148 into '.':
G    lib/Transforms/Utils/SSAUpdater.cpp
--- Reverse-merging r100147 into '.':
U    include/llvm/Transforms/Utils/SSAUpdater.h
G    lib/Transforms/Utils/SSAUpdater.cpp
--- Reverse-merging r100131 into '.':
G    include/llvm/Transforms/Utils/SSAUpdater.h
G    lib/Transforms/Utils/SSAUpdater.cpp
--- Reverse-merging r100130 into '.':
G    lib/Transforms/Utils/SSAUpdater.cpp
--- Reverse-merging r100126 into '.':
G    include/llvm/Transforms/Utils/SSAUpdater.h
G    lib/Transforms/Utils/SSAUpdater.cpp
--- Reverse-merging r100050 into '.':
D    test/Transforms/GVN/2010-03-31-RedundantPHIs.ll
--- Reverse-merging r100047 into '.':
G    include/llvm/Transforms/Utils/SSAUpdater.h
G    lib/Transforms/Utils/SSAUpdater.cpp

llvm-svn: 100264
2010-04-03 03:50:38 +00:00
Bob Wilson 25f1aefd5b Add a DEBUG_TYPE for the SSAUpdater.
llvm-svn: 100263
2010-04-03 03:28:44 +00:00
Bob Wilson 3c54edf9b3 Recommit 100158 now that the buildbots are happy again.
llvm-svn: 100177
2010-04-02 05:09:46 +00:00
Bob Wilson 0389adcd73 Revert 100158 in case it is causing some of the buildbot problems.
llvm-svn: 100164
2010-04-02 01:22:49 +00:00
Bob Wilson 9af4e118c6 Check for terminating conditions before adding PHIs to the worklists.
This is more efficient than adding them to the worklist and then ignoring them.

llvm-svn: 100158
2010-04-02 00:10:41 +00:00
Bob Wilson 737195069a Remove trailing whitespace.
llvm-svn: 100148
2010-04-01 23:06:38 +00:00
Bob Wilson 37b73d9d3e Rewrite another SSAUpdater function to avoid recursion.
llvm-svn: 100147
2010-04-01 23:05:58 +00:00
Bob Wilson 8409feadf0 Change another SSAUpdater function to avoid recursion.
llvm-svn: 100131
2010-04-01 20:04:30 +00:00
Bob Wilson 043c0406f7 Simplify the code to check for existing PHIs, now that it is only used in
one place.  This removes the template function added in svn 94690.

llvm-svn: 100130
2010-04-01 19:53:48 +00:00
Bob Wilson 38fc88ee5d The SSAUpdater should avoid recursive traversals of the CFG, since that may
blow out the stack for really big functions.  Start by fixing an easy case.

llvm-svn: 100126
2010-04-01 18:46:59 +00:00
Bob Wilson ac229124f4 Rewrite part of the SSAUpdater to be more careful about inserting redundant
PHIs.  The previous algorithm was unable to reliably detect when existing
PHIs in a cycle can be reused.  I'm still working on reducing a testcase.
Radar 7711900.

llvm-svn: 100047
2010-03-31 20:51:00 +00:00
Bob Wilson 7577e948e4 Avoid creating redundant PHIs in SSAUpdater::GetValueInMiddleOfBlock.
This was already being done in SSAUpdater::GetValueAtEndOfBlock so I've
just changed SSAUpdater to check for existing PHIs in both places.

llvm-svn: 94690
2010-01-27 22:01:02 +00:00
David Greene 3774a38fdf Change errs() to dbgs().
llvm-svn: 92603
2010-01-05 01:26:49 +00:00
Chris Lattner eaa25da8bb improve indentation avoid a pointless conversion from weakvh to trackingvh,
no functionality change.

llvm-svn: 91848
2009-12-21 22:43:03 +00:00
Chris Lattner 8fb07c5a21 fix PR5837 by having SSAUpdate reuse phi nodes for the
'GetValueInMiddleOfBlock' case, instead of inserting 
duplicates.

A similar fix is almost certainly needed by the machine-level
SSAUpdate implementation.

llvm-svn: 91820
2009-12-21 07:16:11 +00:00
Chris Lattner 2bd9609992 add an assert to make it really clear what this is doing. Return singularval as
a compile time perf optimization to avoid a load.

llvm-svn: 90507
2009-12-04 01:03:32 +00:00
Chris Lattner 7f903681ac alternate fix for PR5258 which avoids worklist problems, with reduced testcase.
llvm-svn: 84667
2009-10-20 20:27:49 +00:00
Torok Edwin cf10ec951d Fix PR5258, jump-threading creating invalid PHIs.
When an incoming value for a PHI is updated, we must also updated all other
incoming values for the same BB to match, otherwise we create invalid PHIs.

llvm-svn: 84638
2009-10-20 15:42:00 +00:00
Duncan Sands 0058c7bcb0 Strip trailing white space.
llvm-svn: 84256
2009-10-16 15:20:13 +00:00
Chris Lattner 9c382cebc5 add a simple helper method.
llvm-svn: 83745
2009-10-10 23:41:48 +00:00
Chris Lattner 249265de06 add ability for clients of SSAUpdater to find out about the
PHI nodes inserted.

llvm-svn: 83744
2009-10-10 23:15:24 +00:00
Chris Lattner 67cdd8b567 add the ability to get a rewritten value from the middle of a block,
not just at the end.  Add a big comment explaining when this could
be useful (which never happens for jump threading).

llvm-svn: 83741
2009-10-10 23:00:11 +00:00
Chris Lattner e474a8d3a7 rename GetValueInBlock -> GetValueAtEndOfBlock to better reflect
what it does.

llvm-svn: 83740
2009-10-10 22:41:58 +00:00
Chris Lattner 65e69a77e1 use a typedef instead of spelling out an insane type. Yay for auto someday.
llvm-svn: 83707
2009-10-10 09:09:20 +00:00
Chris Lattner 60d4e69c81 Implement an efficient and fully general SSA update mechanism that
works on unstructured CFGs.  This implements PR217, our oldest open PR.

llvm-svn: 83705
2009-10-10 09:04:27 +00:00