Commit Graph

169 Commits

Author SHA1 Message Date
Jakub Staszak
f227b50a8e Calculate GetBestDestForJumpOnUndef correctly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133946 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-27 21:51:12 +00:00
Frits van Bommel
5649ba70fb Add a parameter to ConstantFoldTerminator() that callers can use to ask it to also clean up the condition of any conditional terminator it folds to be unconditional, if that turns the condition into dead code. This just means it calls RecursivelyDeleteTriviallyDeadInstructions() in strategic spots. It defaults to the old behavior.
I also changed -simplifycfg, -jump-threading and -codegenprepare to use this to produce slightly better code without any extra cleanup passes (AFAICT this was the only place in -simplifycfg where now-dead conditions of replaced terminators weren't being cleaned up). The only other user of this function is -sccp, but I didn't read that thoroughly enough to figure out whether it might be holding pointers to instructions that could be deleted by this.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131855 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-22 16:24:18 +00:00
Devang Patel
95a7de6b91 Preserve line number information while threading jumps.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130880 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-04 22:48:19 +00:00
Owen Anderson
f6832bbda0 Fix an infinite alternation in JumpThreading where two transforms would repeatedly undo each other. The solution is to perform more aggressive constant folding to make one of the edges just folded away rather than trying to thread it.
Fixes <rdar://problem/9284786>.

Discovered with CSmith.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129538 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-14 21:35:50 +00:00
Jay Foad
3ecfc861b4 Remove PHINode::reserveOperandSpace(). Instead, add a parameter to
PHINode::Create() giving the (known or expected) number of operands.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128537 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-30 11:28:46 +00:00
Jay Foad
d8b4fb4aab (Almost) always call reserveOperandSpace() on newly created PHINodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128535 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-30 11:19:20 +00:00
Chris Lattner
78f7a25f98 prevent jump threading from merging blocks when their address is
taken (and used!).  This prevents merging the blocks (invalidating
the block addresses) in a case like this:

#define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })

void foo() {
  printf("%p\n", _THIS_IP_);
  printf("%p\n", _THIS_IP_);
  printf("%p\n", _THIS_IP_);
}

which fixes PR4151.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125829 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-18 04:43:06 +00:00
Frits van Bommel
01abcf339f Fix a bug in the loop in JumpThreading::ProcessThreadableEdges() where it could falsely produce a MultipleDestSentinel value if the first predecessor ended with an 'indirectbr'. If that happened, it caused an unnecessary FindMostPopularDest() call.
This wasn't a correctness problem, but it broke the fast path for single-predecessor blocks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121966 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-16 12:16:00 +00:00
Frits van Bommel
26e097ca4b Teach jump threading to "look through" a select when the branch direction of a terminator depends on it.
When it sees a promising select it now tries to figure out whether the condition of the select is known in any of the predecessors and if so it maps the operands appropriately.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121859 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15 09:51:20 +00:00
Chris Lattner
e991b5fdd5 simplify code and reduce indentation
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121670 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-13 02:38:13 +00:00
Frits van Bommel
8e8cdc8fe0 Remove some dead code from the jump threading pass.
The last uses of these functions were removed in r113852 when LazyValueInfo was permanently enabled and removed the need for them.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121133 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-07 13:08:07 +00:00
Frits van Bommel
6033b346e2 Implement jump threading of 'indirectbr' by keeping track of whether we're looking for ConstantInt*s or BlockAddress*s.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121066 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-06 23:36:56 +00:00
Frits van Bommel
ea388f217b Refactor jump threading.
Should have no functional change other than the order of two transformations that are mutually-exclusive and the exact formatting of debug output.
Internally, it now stores the ConstantInt*s as Constant*s, and actual undef values instead of nulls.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120946 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-05 19:06:41 +00:00
Frits van Bommel
6f9a8307e0 Remove trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120945 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-05 19:02:47 +00:00
Owen Anderson
081c34b725 Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which
must be called in the pass's constructor.  This function uses static dependency declarations to recursively initialize
the pass's dependencies.

Clients that only create passes through the createFooPass() APIs will require no changes.  Clients that want to use the
CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h
before parsing commandline arguments.

I have tested this with all standard configurations of clang and llvm-gcc on Darwin.  It is possible that there are problems
with the static dependencies that will only be visible with non-standard options.  If you encounter any crash in pass
registration/creation, please send the testcase to me directly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116820 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19 17:21:58 +00:00
Owen Anderson
2ab36d3502 Begin adding static dependence information to passes, which will allow us to
perform initialization without static constructors AND without explicit initialization
by the client.  For the moment, passes are required to initialize both their
(potential) dependencies and any passes they preserve.  I hope to be able to relax
the latter requirement in the future.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116334 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-12 19:48:12 +00:00
Owen Anderson
ce665bd2e2 Now with fewer extraneous semicolons!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115996 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-07 22:25:06 +00:00
Owen Anderson
36c4debc94 Fix PR8247: JumpThreading can cause a block to become unreachable while still having predecessor, if it is part of a self-loop.
Because of this, we cannot use the Simplify* APIs, as they can assert-fail on unreachable code.  Since it's not easy to determine
if a given threading will cause a block to become unreachable, simply defer simplifying simplification to later InstCombine and/or
DCE passes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115082 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-29 20:34:41 +00:00
Owen Anderson
c809d90bca Remove the option to disable LazyValueInfo in JumpThreading, as it is now
on by default and has received significant testing.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113852 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-14 20:57:41 +00:00
Chris Lattner
bdabacdcca Change lower atomic pass to use IntrinsicInst to simplify it a bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113114 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-05 20:10:47 +00:00
Chris Lattner
906a675db8 eliminate some non-obvious casts. UndefValue isa Constant.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113113 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-05 20:03:09 +00:00
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
Owen Anderson
9bfa6fec06 JumpThreading keeps LazyValueInfo up to date, so we don't need to rerun it
if we schedule another LVI-using pass afterwards.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112722 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01 18:27:22 +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
Owen Anderson
0eb355ab6b More cleanups of my JumpThreading transforms, including extracting some duplicated code into a helper function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112634 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-31 20:26:04 +00:00
Owen Anderson
9ba353627a Add an RAII helper to make cleanup of the RecursionSet more fool-proof.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112628 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-31 19:24:27 +00:00
Owen Anderson
c1bdac66ff Refactor my fix for PR5652 to terminate the predecessor lookups after the first failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112620 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-31 18:48:48 +00:00
Owen Anderson
cb21190cbd More Chris-inspired JumpThreading fixes: use ConstantExpr to correctly constant-fold undef, and be more careful with its return value.
This actually exposed an infinite recursion bug in ComputeValueKnownInPredecessors which theoretically already existed (in JumpThreading's
handling of and/or of i1's), but never manifested before.  This patch adds a tracking set to prevent this case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112589 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-31 07:36:34 +00:00
Owen Anderson
327ca7bec2 Re-apply r112539, being more careful to respect the return values of the constant folding methods. Additionally,
use the ConstantExpr::get*() methods to simplify some constant folding.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112550 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-30 23:22:36 +00:00
Owen Anderson
d930f205db Revert r112539. It accidentally introduced a miscompilation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112543 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-30 22:33:41 +00:00
Owen Anderson
1e35610f20 Fixes and cleanups pointed out by Chris. In general, be careful to handle 0 results from ComputeValueKnownInPredecessors
(indicating undef), and re-use existing constant folding APIs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112539 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-30 22:07:52 +00:00
Owen Anderson
fc2fb17fb7 Fix typos in comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112286 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-27 20:32:56 +00:00
Owen Anderson
660cab32fe Use LVI to eliminate conditional branches where we've tested a related condition previously. Update tests for this change.
This fixes PR5652.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112270 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-27 17:12:29 +00:00
Owen Anderson
62efd3b385 Make JumpThreading smart enough to properly thread StrSwitch when it's compiled with clang++.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112198 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-26 17:40:24 +00:00
Owen Anderson
53c36c41ae Turn LVI on, previously detected failures should be fixed now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111923 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-24 17:21:18 +00:00
Owen Anderson
b6ad691ad7 Turn LVI back off, I have a testcase now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111834 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-23 19:59:27 +00:00
Owen Anderson
0e2c359a3e Re-enable LazyValueInfo. Monitoring for failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111816 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-23 18:12:23 +00:00
Owen Anderson
684d8d5b50 Disable LVI while I evaluate a failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111551 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-19 19:47:08 +00:00
Owen Anderson
f2d197b77a Tentatively enabled LVI by default. I'll be monitoring for any failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111543 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-19 19:04:40 +00:00
Owen Anderson
00ac77ef88 Inform LazyValueInfo whenever a block is deleted, to avoid dangling pointer issues.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111382 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-18 18:39:01 +00:00
Chris Lattner
2fa7b48eb5 Fix PR7755: knowing something about an inval for a pred
from the LHS should disable reconsidering that pred on the
RHS.  However, knowing something about the pred on the RHS
shouldn't disable subsequent additions on the RHS from
happening.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111349 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-18 03:14:36 +00:00
Owen Anderson
90c579de5a Reapply r110396, with fixes to appease the Linux buildbot gods.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110460 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-06 18:33:48 +00:00
Owen Anderson
1f74590e9d Revert r110396 to fix buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110410 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-06 00:23:35 +00:00
Owen Anderson
9ccaf53ada Don't use PassInfo* as a type identifier for passes. Instead, use the address of the static
ID member as the sole unique type identifier.  Clean up APIs related to this change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110396 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-05 23:42:04 +00:00
Owen Anderson
f35b08db50 Give JumpThreading+LVI a long-form cl::opt so that it's easier to toggle the default.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110384 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-05 22:11:31 +00:00
Owen Anderson
cfa7fb6df5 Add an initial implementation of LazyValueInfo updating for JumpThreading. Disabled for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109424 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-26 18:48:03 +00:00
Owen Anderson
d13db2c59c Fix batch of converting RegisterPass<> to INTIALIZE_PASS().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109045 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-21 22:09:45 +00:00
Gabor Greif
ee1f44fba3 cache results of operator*
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108142 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-12 14:10:24 +00:00
Chris Lattner
0a96144aac if jump threading is able to infer interesting values on both
the LHS and RHS of an and/or instruction, don't multiply add
known predecessor values.  This fixes the crash on testcase
from PR7498


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108114 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-12 00:47:34 +00:00