Commit Graph

19 Commits

Author SHA1 Message Date
Duncan Sands
fc6e29d4ab Reapply commit 112699, speculatively reverted by echristo, since
I'm sure it is harmless.  Original commit message:
If PrototypeValue is erased in the middle of using the SSAUpdator
then the SSAUpdator may access freed memory.  Instead, simply pass
in the type and name explicitly, which is all that was used anyway.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112810 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-02 08:14:03 +00:00
Eric Christopher
adc581f5cb Speculatively revert 112699 and 112702, they seem to be causing
self host errors on clang-x86-64.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112719 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01 17:29:10 +00:00
Duncan Sands
4d588bceb0 If PrototypeValue is erased in the middle of using the SSAUpdator
then the SSAUpdator may access freed memory.  Instead, simply pass
in the type and name explicitly, which is all that was used anyway.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112699 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01 10:29:33 +00:00
Chris Lattner
ffd9beefb8 implement SSAUpdater::RewriteUseAfterInsertions, a helpful form of RewriteUse.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112409 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-29 04:54:06 +00:00
Bob Wilson
4aad88d1fd Combine the implementations of the core part of the SSAUpdater and
MachineSSAUpdater to avoid duplicating all the code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103060 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-04 23:18:19 +00:00
Bob Wilson
84bd6b0c31 Re-commit my previous SSAUpdater changes. The previous version naively tried
to determine where to place PHIs by iteratively comparing reaching definitions
at each block.  That was just plain wrong.  This version now computes the
dominator tree within the subset of the CFG where PHIs may need to be placed,
and then places the PHIs in the iterated dominance frontier of each definition.
The rest of the patch is mostly the same, with a few more performance
improvements added in.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101612 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-17 03:08:24 +00:00
Bob Wilson
49c283fd3f 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100264 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-03 03:50:38 +00:00
Bob Wilson
6f69035970 Rewrite another SSAUpdater function to avoid recursion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100147 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-01 23:05:58 +00:00
Bob Wilson
33f22e8c66 Change another SSAUpdater function to avoid recursion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100131 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-01 20:04:30 +00:00
Bob Wilson
e8b64281ce 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100126 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-01 18:46:59 +00:00
Bob Wilson
a0c6057061 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100047 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-31 20:51:00 +00:00
Chris Lattner
a25bc44663 comment fix: weakvh -> tracking vh
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91867 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 00:51:57 +00:00
Dan Gohman
bfd5e3d7b1 Add an explicit keyword.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85009 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-24 19:56:23 +00:00
Duncan Sands
ed90342d8a Strip trailing white space.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84256 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-16 15:20:13 +00:00
Chris Lattner
0bef562ea2 add a simple helper method.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83745 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-10 23:41:48 +00:00
Chris Lattner
f5a1fb6b24 add ability for clients of SSAUpdater to find out about the
PHI nodes inserted.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83744 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-10 23:15:24 +00:00
Chris Lattner
1a8d4de397 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).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83741 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-10 23:00:11 +00:00
Chris Lattner
5fb107287f rename GetValueInBlock -> GetValueAtEndOfBlock to better reflect
what it does.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83740 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-10 22:41:58 +00:00
Chris Lattner
93f3bcf7f3 Implement an efficient and fully general SSA update mechanism that
works on unstructured CFGs.  This implements PR217, our oldest open PR.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83705 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-10 09:04:27 +00:00