Commit Graph

185 Commits

Author SHA1 Message Date
Chandler Carruth
a37512049c [PM] Port LoopInfo to the new pass manager, adding both a LoopAnalysis
pass and a LoopPrinterPass with the expected associated wiring.

I've added a RUN line to the only test case (!!!) we have that actually
prints loops. Everything seems to be working.

This is somewhat exciting as this is the first analysis using another
analysis to go in for the new pass manager. =D I also believe it is the
last analysis necessary for porting instcombine, but of course I may yet
discover more.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226560 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-20 10:58:50 +00:00
Chandler Carruth
5a2d01e5b8 [PM] Now that LoopInfo isn't in the Pass type hierarchy, it is much
cleaner to derive from the generic base.

Thise removes a ton of boiler plate code and somewhat strange and
pointless indirections. It also remove a bunch of the previously needed
friend declarations. To fully remove these, I also lifted the verify
logic into the generic LoopInfoBase, which seems good anyways -- it is
generic and useful logic even for the machine side.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226385 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-18 01:25:51 +00:00
Chandler Carruth
e81cec19db [PM] Cleanup more warnings my refactoring exposed where now we have
unused variables in a no-asserts build.

I've fixed this by putting the entire loop behind an #ifndef as it
contains nothing other than asserts.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226377 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-17 14:49:23 +00:00
Chandler Carruth
de5df29556 [PM] Split the LoopInfo object apart from the legacy pass, creating
a LoopInfoWrapperPass to wire the object up to the legacy pass manager.

This switches all the clients of LoopInfo over and paves the way to port
LoopInfo to the new pass manager. No functionality change is intended
with this iteration.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226373 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-17 14:16:18 +00:00
Duncan P. N. Exon Smith
5bf8ade9d0 Revert "IR: MDNode => Value"
Instead, we're going to separate metadata from the Value hierarchy.  See
PR21532.

This reverts commit r221375.
This reverts commit r221373.
This reverts commit r221359.
This reverts commit r221167.
This reverts commit r221027.
This reverts commit r221024.
This reverts commit r221023.
This reverts commit r220995.
This reverts commit r220994.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221711 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-11 21:30:22 +00:00
Duncan P. N. Exon Smith
3a84a6377c IR: MDNode => Value: Instruction::getMetadata()
Change `Instruction::getMetadata()` to return `Value` as part of
PR21433.

Update most callers to use `Instruction::getMDNode()`, which wraps the
result in a `cast_or_null<MDNode>`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221024 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-01 00:10:31 +00:00
Philip Reames
9be9473394 Introduce enum values for previously defined metadata types. (NFC)
Our metadata scheme lazily assigns IDs to string metadata, but we have a mechanism to preassign them as well.  Using a preassigned ID is helpful since we get compile time type checking, and avoid some (minimal) string construction and comparison.  This change adds enum value for three existing metadata types:
+    MD_nontemporal = 9, // "nontemporal"
+    MD_mem_parallel_loop_access = 10, // "llvm.mem.parallel_loop_access"
+    MD_nonnull = 11 // "nonnull"

I went through an updated various uses as well.  I made no attempt to get all uses; I focused on the ones which were easily grepable and easily to translate.  For example, there were several items in LoopInfo.cpp I chose not to update.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220248 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-21 00:13:20 +00:00
Duncan P. N. Exon Smith
facdfc6781 Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges."
This reverts commit r213474 (and r213475), which causes a miscompile on
a stage2 LTO build.  I'll reply on the list in a moment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213562 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:06:51 +00:00
Manuel Jacob
a4697dad19 [C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges.
Summary: This patch introduces two new iterator ranges and updates existing code to use it.  No functional change intended.

Test Plan: All tests (make check-all) still pass.

Reviewers: dblaikie

Reviewed By: dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4481

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213474 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-20 09:10:11 +00:00
Craig Topper
570e52c6f1 [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206243 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-15 04:59:12 +00:00
Eli Bendersky
bbbc2b1140 Consistent use of the noduplicate attribute.
The "noduplicate" attribute of call instructions is sometimes queried directly
and sometimes through the cannotDuplicate() predicate. This patch streamlines
all queries to use the cannotDuplicate() predicate. It also adds this predicate
to InvokeInst, to mirror what CallInst has.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204049 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-17 16:19:07 +00:00
Chandler Carruth
36b699f2b1 [C++11] Add range based accessors for the Use-Def chain of a Value.
This requires a number of steps.
1) Move value_use_iterator into the Value class as an implementation
   detail
2) Change it to actually be a *Use* iterator rather than a *User*
   iterator.
3) Add an adaptor which is a User iterator that always looks through the
   Use to the User.
4) Wrap these in Value::use_iterator and Value::user_iterator typedefs.
5) Add the range adaptors as Value::uses() and Value::users().
6) Update *all* of the callers to correctly distinguish between whether
   they wanted a use_iterator (and to explicitly dig out the User when
   needed), or a user_iterator which makes the Use itself totally
   opaque.

Because #6 requires churning essentially everything that walked the
Use-Def chains, I went ahead and added all of the range adaptors and
switched them to range-based loops where appropriate. Also because the
renaming requires at least churning every line of code, it didn't make
any sense to split these up into multiple commits -- all of which would
touch all of the same lies of code.

The result is still not quite optimal. The Value::use_iterator is a nice
regular iterator, but Value::user_iterator is an iterator over User*s
rather than over the User objects themselves. As a consequence, it fits
a bit awkwardly into the range-based world and it has the weird
extra-dereferencing 'operator->' that so many of our iterators have.
I think this could be fixed by providing something which transforms
a range of T&s into a range of T*s, but that *can* be separated into
another patch, and it isn't yet 100% clear whether this is the right
move.

However, this change gets us most of the benefit and cleans up
a substantial amount of code around Use and User. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203364 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-09 03:16:01 +00:00
Chandler Carruth
03e36d752c [Modules] Move CFG.h to the IR library as it defines graph traits over
IR types.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202827 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-04 11:45:46 +00:00
Benjamin Kramer
d628f19f5d [C++11] Replace llvm::next and llvm::prior with std::next and std::prev.
Remove the old functions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202636 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-02 12:27:27 +00:00
Chandler Carruth
7f2eff792a [PM] Split DominatorTree into a concrete analysis result object which
can be used by both the new pass manager and the old.

This removes it from any of the virtual mess of the pass interfaces and
lets it derive cleanly from the DominatorTreeBase<> template. In turn,
tons of boilerplate interface can be nuked and it turns into a very
straightforward extension of the base DominatorTree interface.

The old analysis pass is now a simple wrapper. The names and style of
this split should match the split between CallGraph and
CallGraphWrapperPass. All of the users of DominatorTree have been
updated to match using many of the same tricks as with CallGraph. The
goal is that the common type remains the resulting DominatorTree rather
than the pass. This will make subsequent work toward the new pass
manager significantly easier.

Also in numerous places things became cleaner because I switched from
re-running the pass (!!! mid way through some other passes run!!!) to
directly recomputing the domtree.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199104 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-13 13:07:17 +00:00
Chandler Carruth
56e1394c88 [cleanup] Move the Dominators.h and Verifier.h headers into the IR
directory. These passes are already defined in the IR library, and it
doesn't make any sense to have the headers in Analysis.

Long term, I think there is going to be a much better way to divide
these matters. The dominators code should be fully separated into the
abstract graph algorithm and have that put in Support where it becomes
obvious that evn Clang's CFGBlock's can use it. Then the verifier can
manually construct dominance information from the Support-driven
interface while the Analysis library can provide a pass which both
caches, reconstructs, and supports a nice update API.

But those are very long term, and so I don't want to leave the really
confusing structure until that day arrives.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199082 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-13 09:26:24 +00:00
Chandler Carruth
560e3955c3 Put the functionality for printing a value to a raw_ostream as an
operand into the Value interface just like the core print method is.
That gives a more conistent organization to the IR printing interfaces
-- they are all attached to the IR objects themselves. Also, update all
the users.

This removes the 'Writer.h' header which contained only a single function
declaration.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198836 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-09 02:29:41 +00:00
Chandler Carruth
bc65a8d518 Move the LLVM IR asm writer header files into the IR directory, as they
are part of the core IR library in order to support dumping and other
basic functionality.

Rename the 'Assembly' include directory to 'AsmParser' to match the
library name and the only functionality left their -- printing has been
in the core IR library for quite some time.

Update all of the #includes to match.

All of this started because I wanted to have the layering in good shape
before I started adding support for printing LLVM IR using the new pass
infrastructure, and commandline support for the new pass infrastructure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198688 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 12:34:26 +00:00
Jakub Staszak
dc9a217d05 Simplify code. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194602 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-13 20:18:38 +00:00
Wan Xiaofei
887f9c5ec1 Quick look-up for block in loop.
This patch implements quick look-up for block in loop by maintaining a hash set for blocks.
It improves the efficiency of loop analysis a lot, the biggest improvement could be 5-6%(458.sjeng).
Below are the compilation time for our benchmark in llc before & after the patch.

Benchmark	llc - trunk		llc - patched	
401.bzip2	0.339081	100.00%	0.329657	102.86%
403.gcc		19.853966	100.00%	19.605466	101.27%
429.mcf		0.049823	100.00%	0.048451	102.83%
433.milc	0.514898	100.00%	0.510217	100.92%
444.namd	1.109328	100.00%	1.103481	100.53%
445.gobmk	4.988028	100.00%	4.929114	101.20%
456.hmmer	0.843871	100.00%	0.825865	102.18%
458.sjeng	0.754238	100.00%	0.714095	105.62%
464.h264ref	2.9668		100.00%	2.90612		102.09%
471.omnetpp	4.556533	100.00%	4.511886	100.99%
bitmnp01	0.038168	100.00%	0.0357		106.91%
idctrn01	0.037745	100.00%	0.037332	101.11%
libquake2	3.78689		100.00%	3.76209		100.66%
libquake_	2.251525	100.00%	2.234104	100.78%
linpack		0.033159	100.00%	0.032788	101.13%
matrix01	0.045319	100.00%	0.043497	104.19%
nbench		0.333161	100.00%	0.329799	101.02%
tblook01	0.017863	100.00%	0.017666	101.12%
ttsprk01	0.054337	100.00%	0.053057	102.41%

Reviewer	: Andrew Trick <atrick@apple.com>, Hal Finkel <hfinkel@anl.gov>
Approver	: Andrew Trick <atrick@apple.com>
Test		: Pass make check-all & llvm test-suite


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193460 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-26 03:08:02 +00:00
Craig Topper
4172a8abba Add 'const' qualifiers to static const char* variables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186371 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-16 01:17:10 +00:00
Paul Redmond
ee21b6f7b4 Add support for llvm.vectorizer metadata
- llvm.loop.parallel metadata has been renamed to llvm.loop to be more generic
  by making the root of additional loop metadata.
  - Loop::isAnnotatedParallel now looks for llvm.loop and associated
    llvm.mem.parallel_loop_access
  - document llvm.loop and update llvm.mem.parallel_loop_access
- add support for llvm.vectorizer.width and llvm.vectorizer.unroll
  - document llvm.vectorizer.* metadata
  - add utility class LoopVectorizerHints for getting/setting loop metadata
  - use llvm.vectorizer.width=1 to indicate already vectorized instead of
    already_vectorized
- update existing tests that used llvm.loop.parallel and
  llvm.vectorizer.already_vectorized

Reviewed by: Nadav Rotem


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182802 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-28 20:00:34 +00:00
Pekka Jaaskelainen
5d0ce79e26 Metadata for annotating loops as parallel. The first consumer for this
metadata is the loop vectorizer.

See the documentation update for more info.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175060 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-13 18:08:57 +00:00
Chandler Carruth
0b8c9a80f2 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00
James Molloy
67ae135759 Add a new attribute, 'noduplicate'. If a function contains a noduplicate call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call.
Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170704 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 16:04:27 +00:00
Chandler Carruth
d04a8d4b33 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169131 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 16:50:05 +00:00
Manman Ren
286c4dc355 Release build: guard dump functions with
"#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)"

No functional change. Update r163344.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163679 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-12 05:06:18 +00:00
Manman Ren
cc77eece74 Release build: guard dump functions with "ifndef NDEBUG"
No functional change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163344 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-06 19:55:56 +00:00
Benjamin Kramer
05d96f98cb Reduce duplicated hash map lookups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162362 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-22 15:37:57 +00:00
Andrew Trick
c9b1e25493 Enable the new LoopInfo algorithm by default.
The primary advantage is that loop optimizations will be applied in a
stable order. This helps debugging and unit test creation. It is also
a better overall implementation without pathologically bad performance
on deep functions.

On large functions (llvm-stress --size=200000 | opt -loops)
Before: 0.1263s
After:  0.0225s

On deep functions (after tweaking llvm-stress, thanks Nadav):
Before: 0.2281s
After:  0.0227s

See r158790 for more comments.

The loop tree is now consistently generated in forward order, but loop
passes are applied in reverse order over the program. If we have a
loop optimization that prefers forward order, that can easily be
achieved by adding a different type of LoopPassManager.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159183 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-26 04:11:38 +00:00
Andrew Trick
5ac3f96c0e Remove unnecessary FIXME
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159182 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-26 04:11:34 +00:00
Andrew Trick
37aa33bc11 A new algorithm for computing LoopInfo. Temporarily disabled.
-stable-loops enables a new algorithm for generating the Loop
forest. It differs from the original algorithm in a few respects:

- Not determined by use-list order.
- Initially guarantees RPO order of block and subloops.
- Linear in the number of CFG edges.
- Nonrecursive.

I didn't want to change the LoopInfo API yet, so the block lists are
still inclusive. This seems strange to me, and it means that building
LoopInfo is not strictly linear, but it may not be a problem in
practice. At least the block lists start out in RPO order now. In the
future we may add an attribute or wrapper analysis that allows other
passes to assume RPO order.

The primary motivation of this work was not to optimize LoopInfo, but
to allow reproducing performance issues by decomposing the compilation
stages. I'm often unable to do this with the current LoopInfo, because
the loop tree order determines Loop pass order. Serializing the IR
tends to invert the order, which reverses the optimization order. This
makes it nearly impossible to debug interdependent loop optimizations
such as LSR.

I also believe this will provide more stable performance results across time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158790 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20 05:23:33 +00:00
Andrew Trick
cbf24b4e58 Move the implementation of LoopInfo into LoopInfoImpl.h.
The implementation only needs inclusion from LoopInfo.cpp and
MachineLoopInfo.cpp. Clients of the interface should only include the
interface. This makes the interface readable and speeds up rebuilds
after modifying the implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158787 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20 03:42:09 +00:00
Andrew Trick
d9fc1ce809 Fix 12513: Loop unrolling breaks with indirect branches.
Take this opportunity to generalize the indirectbr bailout logic for
loop transformations. CFG transformations will never get indirectbr
right, and there's no point trying.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154386 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-10 05:14:42 +00:00
Dan Gohman
f042660197 Move Instruction::isSafeToSpeculativelyExecute out of VMCore and
into Analysis as a standalone function, since there's no need for
it to be in VMCore. Also, update it to use isKnownNonZero and
other goodies available in Analysis, making it more precise,
enabling more aggressive optimization.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146610 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-14 23:49:11 +00:00
Andrew Trick
ed38f1ca2e Remove the temporary flag -disable-unroll-scev and dead code.
SCEV should now be used for trip count analysis, not LoopInfo.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145262 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-28 19:22:09 +00:00
Andrew Trick
5865a8dfde Fix a corner case in updating LoopInfo after fully unrolling an outer loop.
The loop tree's inclusive block lists are painful and expensive to
update. (I have no idea why they're inclusive). The design was
supposed to handle this case but the implementation missed it and my
unit tests weren't thorough enough.

Fixes PR11335: loop unroll update.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144970 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-18 03:42:41 +00:00
Andrew Trick
5434c1e73b LoopInfo::updateUnloop fix, and verify Block->Loop maps.
Fixes an oversight, and adds verification to catch it in the unloop.ll tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138622 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-26 03:06:34 +00:00
Benjamin Kramer
a67f14bf53 Make a bunch of symbols private.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138025 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-19 01:42:18 +00:00
Bill Wendling
c9b2a987a2 Revert r137655. There is some question about whether the 'landingpad'
instruction should be marked as potentially reading and/or writing memory.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137863 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-17 20:36:44 +00:00
Bill Wendling
9d6070f161 Duncan pointed out that the LandingPadInst might read memory. (It might also
write to memory.) Marking it as such makes some checks for immobility go away.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137655 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-15 21:14:31 +00:00
Bill Wendling
da005e7d20 The landingpad instruction isn't loop-invariant.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137628 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-15 18:22:49 +00:00
Duncan Sands
1f6a329f79 Silence a bunch (but not all) "variable written but not read" warnings
when building with assertions disabled.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137460 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-12 14:54:45 +00:00
Andrew Trick
c12d9b9dfb Fix for LoopInfo::updateUnloop. Remove subloop blocks from former
ancestor loops.

I have a unit test that depends on scev-unroll, which unfortunately
isn't checked in. But I will check it in when I can.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137341 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-11 20:27:32 +00:00
Andrew Trick
5c1ff1f2f2 Cleanup. Another thorough review by Nick!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137317 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-11 17:54:58 +00:00
Andrew Trick
fb62b8deb3 Reapplying r136844.
An algorithm for incrementally updating LoopInfo within a
LoopPassManager. The incremental update should be extremely cheap in
most cases and can be used in places where it's not feasible to
regenerate the entire loop forest.

- "Unloop" is a node in the loop tree whose last backedge has been removed.
- Perform reverse dataflow on the block inside Unloop to propagate the
  nearest loop from the block's successors.
- For reducible CFG, each block in unloop is visited exactly
  once. This is because unloop no longer has a backedge and blocks
  within subloops don't change parents.
- Immediate subloops are summarized by the nearest loop reachable from
  their exits or exits within nested subloops.
- At completion the unloop blocks each have a new parent loop, and
  each immediate subloop has a new parent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137276 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-10 23:22:57 +00:00
Andrew Trick
2d31ae3d9d Cleanup. Added LoopBlocksDFS::perform for simple clients.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137195 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-10 01:59:05 +00:00
Andrew Trick
0712108d22 Reverting r136884 updateUnloop, which crashed a linux builder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136857 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-04 01:04:37 +00:00
Andrew Trick
762797d1af An algorithm for incrementally updating LoopInfo within a
LoopPassManager. The incremental update should be extremely cheap in
most cases and can be used in places where it's not feasible to
regenerate the entire loop forest.

- "Unloop" is a node in the loop tree whose last backedge has been removed.
- Perform reverse dataflow on the block inside Unloop to propagate the
  nearest loop from the block's successors.
- For reducible CFG, each block in unloop is visited exactly
  once. This is because unloop no longer has a backedge and blocks
  within subloops don't change parents.
- Immediate subloops are summarized by the nearest loop reachable from
  their exits or exits within nested subloops.
- At completion the unloop blocks each have a new parent loop, and
  each immediate subloop has a new parent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136844 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-03 23:50:25 +00:00
Andrew Trick
882bcc662d whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136843 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-03 23:45:50 +00:00