Commit Graph

330 Commits

Author SHA1 Message Date
Chris Lattner
978796eaad Make GVN be more intelligent about redundant load
elimination: when finding dependent load/stores, realize that
they are the same if aliasing claims must alias instead of relying
on the pointers to be exactly equal.  This makes load elimination
more aggressive.  For example, on 403.gcc, we had:

<     68 gvn    - Number of instructions PRE'd
< 152718 gvn    - Number of instructions deleted
<  49699 gvn    - Number of loads deleted
<   6153 memdep - Number of dirty cached non-local responses
< 169336 memdep - Number of fully cached non-local responses
< 162428 memdep - Number of uncached non-local responses

now we have:

>     64 gvn    - Number of instructions PRE'd
> 153623 gvn    - Number of instructions deleted
>  49856 gvn    - Number of loads deleted
>   5022 memdep - Number of dirty cached non-local responses
> 159030 memdep - Number of fully cached non-local responses
> 162443 memdep - Number of uncached non-local responses

That's an extra 157 loads deleted and extra 905 other instructions nuked.

This slows down GVN very slightly, from 3.91 to 3.96s.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60314 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 01:31:36 +00:00
Chris Lattner
bf145d6e2b Reimplement the non-local dependency data structure in terms of a sorted
vector instead of a densemap.  This shrinks the memory usage of this thing
substantially (the high water mark) as well as making operations like
scanning it faster.  This speeds up memdep slightly, gvn goes from
3.9376 to 3.9118s on 403.gcc

This also splits out the statistics for the cached non-local case to
differentiate between the dirty and clean cached case.  Here's the stats
for 403.gcc:

  6153 memdep - Number of dirty cached non-local responses
169336 memdep - Number of fully cached non-local responses
162428 memdep - Number of uncached non-local responses

yay for caching :)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60313 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 01:15:42 +00:00
Chris Lattner
663e441a75 Cache analyses in ivars and add some useful DEBUG output.
This speeds up GVN from 4.0386s to 3.9376s.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60310 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 00:40:32 +00:00
Chris Lattner
1440ac5417 improve indentation, do cheap checks before expensive ones,
remove some fixme's.  This speeds up GVN very slightly on 403.gcc 
(4.06->4.03s)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60309 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-30 23:39:23 +00:00
Chris Lattner
237a828745 Fix a fixme by making memdep's handling of allocations more logical.
If we see that a load depends on the allocation of its memory with no
intervening stores, we now return a 'None' depedency instead of "Normal".
This tweaks GVN to do its optimization with the new result.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60267 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-30 01:39:32 +00:00
Chris Lattner
396a4a55e5 Change MemDep::getNonLocalDependency to return its results as
a smallvector instead of a DenseMap.  This speeds up GVN by 5%
on 403.gcc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60255 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 21:33:22 +00:00
Chris Lattner
86b29ef64a reimplement getNonLocalDependency with a simpler worklist
formulation that is faster and doesn't require nonLazyHelper.
Much less code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60253 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 21:22:42 +00:00
Chris Lattner
5391a1d804 Split getDependency into getDependency and getDependencyFrom, the
former does caching, the later doesn't.  This dramatically simplifies
the logic in getDependency and getDependencyFrom.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60234 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 03:47:00 +00:00
Chris Lattner
4c72400625 Introduce and use a new MemDepResult class to hold the results of a memdep
query.  This makes it crystal clear what cases can escape from MemDep that
the clients have to handle.  This also gives the clients a nice simplified
interface to it that is easy to poke at.

This patch also makes DepResultTy and MemoryDependenceAnalysis::DepType
private, yay.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60231 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 02:29:27 +00:00
Chris Lattner
39f372e23e Reimplement the internal abstraction used by MemDep in terms
of a pointer/int pair instead of a manually bitmangled pointer.
This forces clients to think a little more about checking the 
appropriate pieces and will be useful for internal 
implementation improvements later.

I'm not particularly happy with this.  After going through this
I don't think that the clients of memdep should be exposed to
the internal type at all.  I'll fix this in a subsequent commit.

This has no functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60230 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 01:43:36 +00:00
Nuno Lopes
7cdd9ee088 fix memleak by cleaning the global sets on pass exit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57353 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-10 16:25:50 +00:00
Duncan Sands
4520dd2b7b Add <cstdio> include where needed by gcc-4.4.
Patch by Samuel Tardieu.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57291 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-08 07:23:46 +00:00
Duncan Sands
5d0392c6b3 Factorize code: remove variants of "strip off
pointer bitcasts and GEP's", and centralize the
logic in Value::getUnderlyingObject.  The
difference with stripPointerCasts is that
stripPointerCasts only strips GEPs if all
indices are zero, while getUnderlyingObject
strips GEPs no matter what the indices are.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56922 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-01 15:25:41 +00:00
Dan Gohman
ae73dc1448 Tidy up several unbeseeming casts from pointer to intptr_t.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55779 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-04 17:05:41 +00:00
Owen Anderson
0c7f91cf84 Fix a bug that prevented PRE from applying in some cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55744 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-03 23:06:07 +00:00
Owen Anderson
516eb1c139 Put a heuristic in place to prevent GVN from falling into bad cases with massively complicated CFGs.
This speeds up a particular testcase from 12+ hours to 5 seconds with little perceptible loss of quality.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55391 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-26 22:07:42 +00:00
Chris Lattner
2dba6a1bdb consolidate DenseMapInfo implementations, and add one for std::pair.
Patch contributed by m-s.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55167 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-22 05:08:25 +00:00
Duncan Sands
6c4d8e3ee4 Supress a gcc-4.3 warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53771 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-18 21:06:02 +00:00
Owen Anderson
e98c54c47c Make PRE actually handle critical edges (by splitting them). Confirmed that bootstrap passes with this change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53762 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-18 18:03:38 +00:00
Owen Anderson
c2b856e5b4 Enable PRE. My last batch of changes fixed the miscompile.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53730 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-17 19:41:00 +00:00
Owen Anderson
b31b06d04b Factor MergeBlockIntoPredecessor out into BasicBlockUtils.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53705 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-17 00:01:40 +00:00
Owen Anderson
5d0af038a7 There's no need to iterate block merging and PRE. In fact, iterating the latter
could cause problems for memdep when it breaks critical edges.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53691 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-16 17:52:31 +00:00
Owen Anderson
2b4f7bbd49 Revert this, as it seems to still be broken.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53627 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-15 17:59:02 +00:00
Owen Anderson
b33f7cc7e6 Enable local PRE by default.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53616 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-15 16:28:23 +00:00
Owen Anderson
961edc8be6 Have GVN do a pre-pass over the CFG that folds away unconditional branches where possible. This allows local PRE to be more aggressive.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53615 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-15 16:28:06 +00:00
Owen Anderson
c45996bf74 Don't call lookupNumber more than we have to.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53470 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-11 20:05:13 +00:00
Owen Anderson
0ae33ef202 Use information already present in the ValueTable to fast-fail when we know there won't be a value number match. This speeds up GVN on a case where there are very few redundancies by ~25%.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53108 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-03 17:44:33 +00:00
Owen Anderson
cb29a4f66a Avoid a redundant call.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53040 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-02 18:15:31 +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
Evan Cheng
2e9f0b1a32 Disable PRE. It's breaking bootstrapping.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52643 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-23 21:22:35 +00:00
Owen Anderson
b70a571c99 Tighten the conditions under which we do PRE, remove some unneeded code, and correct our preserved analyses list, since we
do now change the CFG by splitting critical edges during PRE.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52631 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-23 17:49:45 +00:00
Evan Cheng
4ce138cc55 Enable PRE.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52574 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-21 07:26:53 +00:00
Owen Anderson
f2204d7bb1 Really disable PRE.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52531 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-20 08:59:13 +00:00
Owen Anderson
6fafe847b2 Change around the data structures used to store availability sets, resulting in a GVN+PRE that is faster that GVN alone was before.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52521 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-20 01:15:47 +00:00
Evan Cheng
88d11c03cd Disable PRE for now. It seems to be breaking llvm-gcc bootstrapping.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52518 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-20 01:01:07 +00:00
Owen Anderson
aa0b63422a Add a hidden -disable-pre flag for testing purposes. This should be removed
once benchmarking is completed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52506 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-19 19:57:25 +00:00
Owen Anderson
5c274eebc6 PRE requires that critical edges be split.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52505 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-19 19:54:19 +00:00
Owen Anderson
9da52dce89 Be sure to remove values from the value numbering table after we delete them.
This fixes a failure on povray.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52499 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-19 17:53:26 +00:00
Owen Anderson
3cd8eb314a Revert support for insertvalue and extractvalue instructions for the moment.
GVN expects that all inputs which to an instruction fall somewhere in the value
hierarchy, which isn't true for these.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52496 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-19 17:25:39 +00:00
Owen Anderson
d34ac6e782 Add support for extractvalue and insertvalue instructions in GVN.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52472 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-18 21:59:00 +00:00
Owen Anderson
b230372437 Add local PRE to GVN. This only operates in cases where it would not increase code size, namely when the instantiated expression
would only need to be created in one predecessor.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52471 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-18 21:41:49 +00:00
Owen Anderson
2960ed4b85 We don't want to find dependencies within the same block in this case. It leads to incorrect results because
we're detecting something at or after the call we're querying on.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52433 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-17 22:27:06 +00:00
Owen Anderson
af4240ac2d Switch GVN to use ScopedHashTable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52242 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-12 19:25:32 +00:00
Matthijs Kooijman
845f524c25 Update comments and documentation to reflect that GCSE and ValueNumbering are
deprecated by the GVN and GVNPRE passes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51983 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-05 07:55:49 +00:00
Owen Anderson
10a05bfff0 Remove unneeded #include.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51955 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-04 18:28:10 +00:00
Nate Begeman
1d6e4091f6 Teach GVN to not assert on vector comparisons
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51230 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-18 19:49:05 +00:00
Owen Anderson
c4f406e736 Fix Analysis/BasicAA/pure-const-dce.ll. This turned out to be a correctness
bug as well as a missed optimization.  We weren't properly checking for local
dependencies before moving on to non-local ones when doing non-local read-only 
call CSE.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51082 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-13 23:18:30 +00:00
Owen Anderson
16db1f70b7 Make the non-local CSE safety checks slightly more thorough.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51035 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-13 13:41:23 +00:00
Owen Anderson
3b3f58cb77 Add support for non-local CSE of read-only calls.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51024 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-13 08:17:22 +00:00
Owen Anderson
a472c4a280 Go back to passing the analyses around as parameters.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50995 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-12 20:15:55 +00:00
Owen Anderson
7b45e33107 Move the various analyses used by GVN into static variables so we don't have to keep passing them around or refetching them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50963 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-12 08:15:27 +00:00
Owen Anderson
4bda6e47e9 Remove unneeded #include's.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50035 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-21 07:47:38 +00:00
Owen Anderson
241f65321e Make GVN able to remove unnecessary calls to read-only functions again.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49842 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-17 05:36:50 +00:00
Owen Anderson
8f46c78fcc Fix PR2213 by simultaneously making GVN more aggressive with the return values
of calls and less aggressive with non-readnone calls.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49516 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-11 05:11:49 +00:00
Owen Anderson
a723d1e48f Factor a bunch of functionality related to memcpy and memset transforms out of
GVN and into its own pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49419 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-09 08:23:16 +00:00
Owen Anderson
82a66291b0 Remove accidentally duplicated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49418 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-09 07:55:01 +00:00
Owen Anderson
412821284f Add operator= implementations to SparseBitVector, allowing it to be used in GVN. This results
in both time and memory savings for GVN.  For example, one testcase went from 10.5s to 6s with
this patch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49345 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-07 17:38:23 +00:00
Owen Anderson
e5ffa900f8 Make GVN more memory efficient, particularly on code that contains a large number of
allocations, which GVN can't optimize anyways.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49329 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-07 09:59:07 +00:00
Gabor Greif
051a950000 API changes for class Use size reduction, wave 1.
Specifically, introduction of XXX::Create methods
for Users that have a potentially variable number of
Uses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49277 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-06 20:25:17 +00:00
Chris Lattner
97ae12a988 change iterator invalidation avoidance to just move the iterator backward
when something changes, instead of moving forward.  This allows us to 
simplify memset lowering, inserting the memset at the end of the range of 
stuff we're touching instead of at the start.

This, in turn, allows us to make use of the addressing instructions already
used in the function instead of inserting our own.  For example, we now
codegen:

	%tmp41 = getelementptr [8 x i8]* %ref_idx, i32 0, i32 0		; <i8*> [#uses=2]
	call void @llvm.memset.i64( i8* %tmp41, i8 -1, i64 8, i32 1 )

instead of:

	%tmp20 = getelementptr [8 x i8]* %ref_idx, i32 0, i32 7		; <i8*> [#uses=1]
	%ptroffset = getelementptr i8* %tmp20, i64 -7		; <i8*> [#uses=1]
	call void @llvm.memset.i64( i8* %ptroffset, i8 -1, i64 8, i32 1 )



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48940 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-29 05:15:47 +00:00
Chris Lattner
d22fe2b51f make the common case of a single store (which clearly shouldn't be turned
into a memset!) faster by avoiding an allocation of an std::list node.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48939 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-29 04:52:12 +00:00
Chris Lattner
9f8a6a7498 give form-memset a significantly more sane heuristic, enable it by default.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48937 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-29 04:36:18 +00:00
Chris Lattner
7f0965e7da make memset inference significantly more powerful: it can now handle
memsets that initialize "structs of arrays" and other store sequences
that are not sequential.  This is still only enabled if you pass 
-form-memset-from-stores.  The flag is not heavily tested and I haven't
analyzed the perf regressions when -form-memset-from-stores is passed
either, but this causes no make check regressions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48909 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-28 06:45:13 +00:00
Evan Cheng
88ffdddcc4 Temporarily disabling memset forming optimization. Add an option.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48720 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-24 05:28:38 +00:00
Chris Lattner
b017c9e89c implement an initial hack at a straight-line store -> memset optimization.
This fires dozens of times across spec and multisource, but I don't know
if it actually speeds stuff up.  Hopefully the testers will show something
nice :)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48680 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-22 05:37:16 +00:00
Chris Lattner
d27290d733 implement the logic for memset insertion and store deletion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48679 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-22 04:13:49 +00:00
Chris Lattner
641dae19eb This is a partially implemented and currently disabled start of a store
merging optimization.  Nothing to see here, hopefully more later :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48670 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-22 00:31:52 +00:00
Chris Lattner
8e1e95cb04 the size of a smallvector shouldn't be part of the interface to these methods.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48662 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 22:01:16 +00:00
Chris Lattner
2e60701b9d make gvn marginally faster by reallocating the lastSeenLoad map for
each basic block.


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2008-03-21 21:33:23 +00:00
Chris Lattner
88365bb404 Minor cleanups and shrinkification.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48658 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 21:14:38 +00:00
Owen Anderson
8a97fddbc2 Fix a bug in GVN that Duncan noticed, where we potentially need to insert a
pointer bitcast when performing return slot optimization.


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2008-03-13 22:07:10 +00:00
Owen Anderson
6bb0bd52ec Improve the return slot optimization to be both more aggressive (not limited to sret parameters), and
safer (when the passed pointer might be invalid).  Thanks to Duncan and Chris for the idea behind this, 
and extra thanks to Duncan for helping me work out the trap-safety.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48280 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-12 07:37:44 +00:00
Owen Anderson
77db50f68f Fix an issue where GVN had the sizes of the two memcpy's reverse, resulting
in an invalid transformation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47639 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-26 23:06:17 +00:00
Owen Anderson
c0808a7e1d Fix an issue where GVN was performing the return slot optimization when it was
not safe.  This is fixed by more aggressively checking that the return slot is
not used elsewhere in the function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47544 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-25 04:08:09 +00:00
Owen Anderson
0f7ea1ab10 Fix an issue where GVN would try to use an instruction before its definition when performing return slot optimization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47541 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-25 00:40:41 +00:00
Anton Korobeynikov
07e6e56f57 Make Transforms to be 4.3 warnings-clean
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47371 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 11:26:25 +00:00
Owen Anderson
61d30a821f When performing return slot optimization, remember to inform memdep when we're removing the memcpy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47364 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 08:23:02 +00:00
Owen Anderson
967552e7ec Refactor this method a bit, and correct a test that was completely wrong but happened to work out anyways. :-)
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2008-02-19 07:07:51 +00:00
Chris Lattner
e42ce73c37 isa+cast -> dyncast.
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2008-02-19 06:53:20 +00:00
Chris Lattner
0a76a621a4 simplify this code again, try 2 :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47319 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 06:52:38 +00:00
Owen Anderson
9cffa9a6ed Fix a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47318 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 06:51:23 +00:00
Owen Anderson
61c24e96b1 Major improvements to yesterday's return slot optimization. Remove some unneccessary constraints,
and add some others that should have been in from the first place.  Document the whole thing better.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47315 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 06:35:43 +00:00
Owen Anderson
fa113f8155 Factor the profitability check for return slot optimization out into a static function.
At some point in the future, this check will become smarter.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47310 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 03:27:34 +00:00
Owen Anderson
c0755a6f98 An sret parameter is required to be the first parameter, so there's no need to loop
over all the parameters of the callee looking for it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47309 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 03:15:29 +00:00
Owen Anderson
7acc0af95a Cleanup some of my patches from yesterday. Refactor the check for which xform
to apply to a memcpy into processInstruction.  Also, fix a bug in the check due to
missing braces.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47307 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 03:09:45 +00:00
Owen Anderson
c2580ab9b0 Fix Transforms/GVN/memcpy.ll, which Chris broke in r47275 by reordering the branches. memcpy's are a kind of CallInst.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47305 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 02:53:23 +00:00
Chris Lattner
913b19f6fc minor code simplification, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47275 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18 17:47:29 +00:00
Owen Anderson
5aa4f2a085 Add support to GVN for performing sret return slot optimization. This means that, if an sret function tail calls
another sret function, it should pass its own sret parameter to the tail callee, allowing it to fill in the correct
return value.  llvm-gcc does not emit this by default.  Instead, it allocates space in the caller for the sret of
the tail call and then uses memcpy to copy the result into the caller's sret parameter.  This optimization detects
and optimizes that case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47265 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18 09:24:53 +00:00
Nick Lewycky
95f0ba2703 Fix PR2032. Inform the alias analysis of changes to the underlying program.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47111 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-14 07:11:24 +00:00
Owen Anderson
30b4bd4d10 Re-apply the patch to improve the optimizations of memcpy's, with several
bugs fixed.  This now passes PPC bootstrap.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47026 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-12 21:15:18 +00:00
Eli Friedman
b6c36e4058 Fix for bug 1996: optimize out loads of undef. This code basically just
checks for a malloc/alloca immediately followed by a load.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47006 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-12 12:08:14 +00:00
Bill Wendling
e00fec554b Temporarily reverting:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20080128/057882.html

This is causing a miscompilation on PPC G5 and just now seeing it on iMac x86-64.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46822 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-06 20:03:07 +00:00
Owen Anderson
6f7a52d300 Allow GVN to hack on memcpy's, making them open to further optimization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46693 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-04 02:59:58 +00:00
Chris Lattner
4ee451de36 Remove attribution from file headers, per discussion on llvmdev.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45418 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-29 20:36:04 +00:00
Owen Anderson
5fc4abac3d Fix several cache coherence bugs in MemDep/GVN that were found. Also add some (disabled) debugging code
to make such problems easier to diagnose in the future, written by Duncan Sands.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44695 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-08 01:37:09 +00:00
Duncan Sands
dff6710717 Integrate the readonly/readnone logic more deeply
into alias analysis.  This meant updating the API
which now has versions of the getModRefBehavior,
doesNotAccessMemory and onlyReadsMemory methods
which take a callsite parameter.  These should be
used unless the callsite is not known, since in
general they can do a better job than the versions
that take a function.  Also, users should no longer
call the version of getModRefBehavior that takes
both a function and a callsite.  To reduce the
chance of misuse it is now protected.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44487 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-01 07:51:45 +00:00
Owen Anderson
1fb136464d Fix a miscompilation in spiff on PPC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44437 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-29 18:02:22 +00:00
Owen Anderson
a16bbc9aa7 Fix another bug that was causing siod to fail.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44325 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-26 07:17:19 +00:00
Owen Anderson
00a6d1448d Allow GVN to eliminate read-only function calls when it can detect that they are redundant.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44323 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-26 02:26:36 +00:00
Owen Anderson
b388ca9544 Allow GVN to eliminate redundant calls to functions without side effects.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43147 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-18 19:39:33 +00:00
Owen Anderson
ce4d88aa64 Add partial caching of non-local memory dependence queries. This provides a modest
speedup for GVN.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42185 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-21 03:53:52 +00:00
Chris Lattner
76c1b97e40 Merge DenseMapKeyInfo & DenseMapValueInfo into DenseMapInfo
Add a new DenseMapInfo::isEqual method to allow clients to redefine
the equality predicate used when probing the hash table.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42042 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-17 18:34:04 +00:00
Owen Anderson
2486686689 Be more careful when constant-folding PHI nodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41998 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-16 08:04:16 +00:00
Owen Anderson
1defe2df5d Factor out some code into a helper function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41131 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-16 22:51:56 +00:00
Owen Anderson
62bc33c954 Add some more comments to GVN.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41129 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-16 22:02:55 +00:00
Owen Anderson
31f496755a Eliminate PHI nodes with constant values during normal GVN processing, even when
they're not related to eliminating a load.


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2007-08-14 18:33:27 +00:00
Owen Anderson
36057c7834 Be more aggressive in pruning unnecessary PHI nodes when doing PHI construction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41080 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-14 18:16:29 +00:00
Owen Anderson
3e75a42ee2 Make GVN iterative.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41078 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-14 18:04:11 +00:00
Owen Anderson
8e8278e7fe Fix a case where GVN was failing to return true when it had, in fact, modified
the function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41077 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-14 17:59:48 +00:00
Owen Anderson
9528f11481 Make NonLocal and None const in the right way. :-)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40961 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-09 04:42:44 +00:00
Owen Anderson
8cad423d94 Change the None and NonLocal markers in memdep to be const.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40946 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-08 21:39:39 +00:00
Owen Anderson
a37226af81 Don't insert nearly as many redundant phi nodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40909 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-07 23:12:31 +00:00
Owen Anderson
ab8702787d Fix a subtle miscompilation. This allows 197.parser to be compiled correctly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40791 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-03 19:59:35 +00:00
Owen Anderson
4b55c3b0f1 Fix a subtle iterator invalidation bug in a recursive algorithm.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40776 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-03 11:03:26 +00:00
Owen Anderson
830db6a00e Fix 80 col. violations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40750 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-02 18:16:06 +00:00
Owen Anderson
1c2763d3fe Fix a bug that was causing several miscompilations on SPEC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40746 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-02 17:56:05 +00:00
Owen Anderson
9066020993 Make non-local memdep not be recursive, and fix a bug on 403.gcc that this exposed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40692 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-01 22:01:54 +00:00
Owen Anderson
bf7d0bc4e5 Don't let the memory allocator outsmart GVN. ;-)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40655 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-31 23:27:13 +00:00
Owen Anderson
b95f9d565f Fix a failure I accidentally caused in my last commit by mishandling the
removal of redundant phis.


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2007-07-31 20:18:28 +00:00
Owen Anderson
054ab94bff Fix a misoptimization in aha.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40642 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-31 17:43:14 +00:00
Owen Anderson
891eecb040 Avoid potential iterator invalidation problems.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40607 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-30 21:26:39 +00:00
Owen Anderson
45c8388e2a Use more caching when computing non-local dependence. This makes bzip2 not
use up the entire 32-bit address space.


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2007-07-30 17:29:24 +00:00
Owen Anderson
4f9ba7c40c Fix a bug caused by indiscriminantly asking for the dominators of a predecessor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40595 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-30 16:57:08 +00:00
Owen Anderson
45537917ee Fix a couple more bugs in the phi construction by pulling in code that does
almost the same things from LCSSA.


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2007-07-26 18:26:51 +00:00
Owen Anderson
febc7e3613 Fix what is _hopefully_ the last corner case for loops.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40503 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-25 23:54:42 +00:00
Owen Anderson
9f435740b1 My last commit was not correct for nested loops. Fix it, and add a testcase for it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40498 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-25 22:19:40 +00:00
Owen Anderson
0d16988690 Fix an infinite loop on 300.twolf.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40497 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-25 22:03:06 +00:00
Owen Anderson
2e3d6b4a27 Fix a bug that was causing GVN to crash on 252.eon.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40494 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-25 21:13:41 +00:00
Owen Anderson
0cd320362e Add basic support for performing whole-function RLE.
Note: This has not yet been thoroughly tested.  Use at your own risk.


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2007-07-25 19:57:03 +00:00
Owen Anderson
1ad2cb7555 Add a GVN pass, using the value numbering code I developed for GVNPRE and the
load elimination code from RedundantLoadElimination.


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2007-07-24 17:55:58 +00:00