181 Commits

Author SHA1 Message Date
Benjamin Kramer
66f3fb9fac Use phi ranges to simplify code. No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321585 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-30 15:27:33 +00:00
Brian M. Rzycki
d76ae1215c Reverting [JumpThreading] Preservation of DT and LVI across the pass
Stage 2 bootstrap failed:
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules-2/builds/14434



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320641 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-13 22:01:17 +00:00
Brian M. Rzycki
7cc3dcfb80 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320612 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-13 20:52:26 +00:00
Adrian Prantl
f14c45fbab loop-rotate: eliminate duplicate debug intrinsics after splicing.
Fixes part of PR35113.

This reapplies r317105 with an additional check for isa<Instruction>
as found by the bots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317120 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01 20:43:30 +00:00
Adrian Prantl
f0b2742b3d Revert r317105 to investigate bot breakage.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317110 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01 18:06:38 +00:00
Adrian Prantl
3dc28623cf loop-rotate: eliminate duplicate debug intrinsics after splicing.
Fixes part of PR35113.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317105 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01 17:28:47 +00:00
Eugene Zelenko
16267f1cbc [Transforms] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316724 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-27 01:09:08 +00:00
Sanjoy Das
399b4d037d Rename WeakVH to WeakTrackingVH; NFC
This relands r301424.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301812 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-01 17:07:49 +00:00
Sanjoy Das
263da12ab2 Reverts commit r301424, r301425 and r301426
Commits were:

"Use WeakVH instead of WeakTrackingVH in AliasSetTracker's UnkownInsts"
"Add a new WeakVH value handle; NFC"
"Rename WeakVH to WeakTrackingVH; NFC"

The changes assumed pointers are 8 byte aligned on all architectures.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301429 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-26 16:37:05 +00:00
Sanjoy Das
d0cf26e443 Rename WeakVH to WeakTrackingVH; NFC
Summary:
I plan to use WeakVH to mean "nulls itself out on deletion, but does
not track RAUW" in a subsequent commit.

Reviewers: dblaikie, davide

Reviewed By: davide

Subscribers: arsenm, mehdi_amini, mcrosier, mzolotukhin, jfb, llvm-commits, nhaehnle

Differential Revision: https://reviews.llvm.org/D32266

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301424 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-26 16:20:52 +00:00
Michael Kruse
240ae8590d [BasicBlockUtils] Check for nullptr before updating LoopInfo.
LoopInfo::getLoopFor returns nullptr if a BB is not in a loop and only
then can the loop be updated to contain the newly created BBs. Add the
missing nullptr check to SplitBlockAndInsertIfThen.

Within LLVM, the only user of this function that also passes a LoopInfo
to be updated is InnerLoopVectorizer::predicateInstructions().
As the method's name implies, the BB operataten on will always be within
a loop, but out-of-tree users may also use it differently (here: Polly).

All other uses of LoopInfo::getLoopFor in the file properly check its
return value for nullptr.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297016 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-06 15:33:05 +00:00
Taewook Oh
38fa7051aa [BasicBlockUtils] Use getFirstNonPHIOrDbg to set debugloc for instructions created in SplitBlockPredecessors
Summary:
When setting debugloc for instructions created in SplitBlockPredecessors, current implementation copies debugloc from the first-non-phi instruction of the original basic block. However, if the first-non-phi instruction is a call for @llvm.dbg.value, the debugloc of the instruction may point the location outside of the block itself. For the example code of

```
  1 typedef struct _node_t {
  2   struct _node_t *next;
  3 } node_t;
  4
  5 extern node_t *root;
  6
  7 int foo() {
  8   node_t *node, *tmp;
  9   int ret = 0;
 10
 11   node = tmp = root->next;
 12   while (node != root) {
 13     while (node) {
 14       tmp = node;
 15       node = node->next;
 16       ret++;
 17     }
 18   }
 19
 20   return ret;
 21 }
```

, below is the basicblock corresponding to line 12 after Reassociate expressions pass:

```
while.cond:                                       ; preds = %while.cond2, %entry
  %node.0 = phi %struct._node_t* [ %1, %entry ], [ null, %while.cond2 ]
  %ret.0 = phi i32 [ 0, %entry ], [ %ret.1, %while.cond2 ]
  tail call void @llvm.dbg.value(metadata i32 %ret.0, i64 0, metadata !19, metadata !20), !dbg !21
  tail call void @llvm.dbg.value(metadata %struct._node_t* %node.0, i64 0, metadata !11, metadata !20), !dbg !31
  %cmp = icmp eq %struct._node_t* %node.0, %0, !dbg !33
  br i1 %cmp, label %while.end5, label %while.cond2, !dbg !35
```

As you can see, the first-non-phi instruction is a call for @llvm.dbg.value, and the debugloc is

```
!21 = !DILocation(line: 9, column: 7, scope: !6)
```

, which is a definition of 'ret' variable and outside of the scope of the basicblock itself. However, current implementation picks up this debugloc for the instructions created in SplitBlockPredecessors. This patch addresses this problem by picking up debugloc from the first-non-phi-non-dbg instruction.

Reviewers: dblaikie, samsonov, eugenis

Reviewed By: eugenis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29867

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295106 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-14 21:10:40 +00:00
Benjamin Kramer
5288df58b7 Apply clang-tidy's modernize-loop-convert to most of lib/Transforms.
Only minor manual fixes. No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273808 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-26 12:28:59 +00:00
Sanjay Patel
e524aca898 improve documentation comments; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267292 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-23 16:31:48 +00:00
Adam Nemet
31bf7f9ec0 [LV] Preserve LoopInfo when store predication is used
This was a latent bug that got exposed by the change to add LoopSimplify
as a dependence to LoopLoadElimination.  Since LoopInfo was corrupted
after LV, LoopSimplify mis-compiled nbench in the test-suite (more
details in the PR).

The problem was that when we create the blocks for predicated stores we
didn't add those to any loops.

The original testcase for store predication provides coverage for this
assuming we verify LI on the way out of LV.

Fixes PR26952.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@263565 91177308-0d34-0410-b5e6-96231b3b80d8
2016-03-15 18:06:20 +00:00
Chandler Carruth
c5266b5293 [PM] Port memdep to the new pass manager.
This is a fairly straightforward port to the new pass manager with one
exception. It removes a very questionable use of releaseMemory() in
the old pass to invalidate its caches between runs on a function.
I don't think this is really guaranteed to be safe. I've just used the
more direct port to the new PM to address this by nuking the results
object each time the pass runs. While this could cause some minor malloc
traffic increase, I don't expect the compile time performance hit to be
noticable, and it makes the correctness and other aspects of the pass
much easier to reason about. In some cases, it may make things faster by
making the sets and maps smaller with better locality. Indeed, the
measurements collected by Bruno (thanks!!!) show mostly compile time
improvements.

There is sadly very limited testing at this point as there are only two
tests of memdep, and both rely on GVN. I'll be porting GVN next and that
will exercise this heavily though.

Differential Revision: http://reviews.llvm.org/D17962

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@263082 91177308-0d34-0410-b5e6-96231b3b80d8
2016-03-10 00:55:30 +00:00
Chen Li
a03271ee00 [SplitLandingPadPredecessors] Create a PHINode for the original landingpad only if it has some uses
Summary: This patch adds a check in SplitLandingPadPredecessors to see if the original landingpad instruction has any uses. If not, we don't need to create a PHINode for it in the joint block since it's gonna be a dead code anyway. The motivation for this patch is that we found a bug that SplitLandingPadPredecessors created a PHINode of token type landingpad, which failed the verifier since PHINode can not be token type. However, the created PHINode will never be used in our code pattern. This patch will workaround this bug, and we might add supports in SplitLandingPadPredecessors to handle token type landingpad with uses in the future.

Reviewers: reames

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15835

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256972 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-06 20:32:05 +00:00
Duncan P. N. Exon Smith
5270f8871a TransformUtils: Remove implicit ilist iterator conversions, NFC
Continuing the work from last week to remove implicit ilist iterator
conversions.  First related commit was probably r249767, with some more
motivation in r249925.  This edition gets LLVMTransformUtils compiling
without the implicit conversions.

No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250142 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-13 02:39:05 +00:00
Pete Cooper
be21eab7ac Convert a bunch of loops to foreach. NFC.
After r244074, we now have a successors() method to iterate over
all the successors of a TerminatorInst.  This commit changes a bunch
of eligible loops to use it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@244260 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-06 20:22:46 +00:00
David Majnemer
4a45f0871a New EH representation for MSVC compatibility
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support.  Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.

Differential Revision: http://reviews.llvm.org/D11097

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243766 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-31 17:58:14 +00:00
Chandler Carruth
f020cb2f75 [PM/AA] Remove all of the dead AliasAnalysis pointers being threaded
through APIs that are no longer necessary now that the update API has
been removed.

This will make changes to the AA interfaces significantly less
disruptive (I hope). Either way, it seems like a really nice cleanup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242882 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-22 09:52:54 +00:00
Chandler Carruth
ac17c4d9b5 [PM/AA] Remove the last of the legacy update API from AliasAnalysis as
part of simplifying its interface and usage in preparation for porting
to work with the new pass manager.

Note that this will likely expose that we have dead arguments, members,
and maybe even pass requirements for AA. I'll be cleaning those up in
seperate patches. This just zaps the actual update API.

Differential Revision: http://reviews.llvm.org/D11325

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242881 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-22 09:49:59 +00:00
Chandler Carruth
c51f300513 [PM/AA] Completely remove the AliasAnalysis::copyValue interface.
No in-tree alias analysis used this facility, and it was not called in
any particularly rigorous way, so it seems unlikely to be correct.

Note that one of the only stateful AA implementations in-tree,
GlobalsModRef is completely broken currently (and any AA passes like it
are equally broken) because Module AA passes are not effectively
invalidated when a function pass that fails to update the AA stack runs.

Ultimately, it doesn't seem like we know how we want to build stateful
AA, and until then trying to support and maintain correctness for an
untested API is essentially impossible. To that end, I'm planning to rip
out all of the update API. It can return if and when we need it and know
how to build it on top of the new pass manager and as part of *tested*
stateful AA implementations in the tree.

Differential Revision: http://reviews.llvm.org/D10889

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241975 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-11 04:39:00 +00:00
David Majnemer
eddf9e2057 Revert the new EH instructions
This reverts commits r241888-r241891, I didn't mean to commit them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241893 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-10 07:15:17 +00:00
David Majnemer
751c4be705 New EH representation for MSVC compatibility
Summary:
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support.  Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.

Reviewers: rnk, JosephTremoulet, reames, nlewycky, rjmccall

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11041

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241888 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-10 07:00:44 +00:00
Alexey Samsonov
a9a3bc268b Let llvm::ReplaceInstWithInst copy debug location from old to new instruction.
Currently some users of this function do this explicitly, and all the
rest forget to do this.

ThreadSanitizer was one of such users, and had missing debug
locations for calls into TSan runtime handling atomic operations,
eventually leading to poorly symbolized stack traces and malfunctioning
suppressions.

This is another change relevant to PR23837.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240460 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-23 21:00:08 +00:00
Alexey Samsonov
8478c82b28 [BasicBlockUtils] Set debug locations for instructions created in SplitBlockPredecessors.
Test Plan: regression test suite

Reviewers: eugenis, dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10343

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239438 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-09 22:10:29 +00:00
Pete Cooper
f23c6af13d Convert PHI getIncomingValue() to foreach over incoming_values(). NFC.
We already had a method to iterate over all the incoming values of a PHI.  This just changes all eligible code to use it.

Ineligible code included anything which cared about the index, or was also trying to get the i'th incoming BB.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237169 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-12 20:05:31 +00:00
Philip Reames
61a76b2d4a Teach SplitBlockPredecessors how to handle landingpad blocks.
Patch by: Igor Laevsky <igor@azulsystems.com>

"Currently SplitBlockPredecessors generates incorrect code in case if basic block we are going to split has a landingpad. Also seems like it is fairly common case among it's users to conditionally call either SplitBlockPredecessors or SplitLandingPadPredecessors. Because of this I think it is reasonable to add this condition directly into SplitBlockPredecessors."

Differential Revision: http://reviews.llvm.org/D7157



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227390 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-28 23:06:47 +00:00
Chandler Carruth
10b853882c [PM] Replace the Pass argument to SplitEdge with specific analyses used
and updated.

This may appear to remove handling for things like alias analysis when
splitting critical edges here, but in fact no callers of SplitEdge
relied on this. Similarly, all of them wanted to preserve LCSSA if there
was any update of the loop info. That makes the interface much simpler.

With this, all of BasicBlockUtils.h is free of Pass arguments and
prepared for the new pass manager. This is tho majority of utilities
that relied on pass arguments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226459 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 12:36:53 +00:00
Chandler Carruth
08962f208b [PM] Remove the Pass argument from all of the critical edge splitting
APIs and replace it and numerous booleans with an option struct.

The critical edge splitting API has a really large surface of flags and
so it seems worth burning a small option struct / builder. This struct
can be constructed with the various preserved analyses and then flags
can be flipped in a builder style.

The various users are now responsible for directly passing along their
analysis information. This should be enough for the critical edge
splitting to work cleanly with the new pass manager as well.

This API is still pretty crufty and could be cleaned up a lot, but I've
focused on this change just threading an option struct rather than
a pass through the API.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226456 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 12:09:11 +00:00
Chandler Carruth
d09c0db8a9 [PM] Lift the analyses into the interface for
SplitLandingPadPredecessors and remove the Pass argument from its
interface.

Another step to the utilities being usable with both old and new pass
managers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226426 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 03:03:39 +00:00
Chandler Carruth
5817eaff8f [PM] Pull the analyses used for another utility routine into its API
rather than relying on the pass object.

This one is a bit annoying, but will pay off. First, supporting this one
will make the next one much easier, and for utilities like LoopSimplify,
this is moving them (slowly) closer to not having to pass the pass
object around throughout their APIs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226396 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-18 09:21:15 +00:00
Chandler Carruth
7478e27573 [PM] Sink the specific analyses preserved by SplitBlock into its
interface, removing Pass from its interface.

This also makes those analyses optional so that passes which don't even
preserve these (or use them) can skip the logic entirely.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226394 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-18 02:39:37 +00:00
Chandler Carruth
0389537c08 [PM] Replace another Pass argument with specific analyses that are
optionally updated by MergeBlockIntoPredecessors.

No functionality changed, just refactoring to clear the way for the new
pass manager.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226392 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-18 02:11:23 +00:00
Chandler Carruth
b7f66977be [PM] Lift the actual analyses used into the inferface rather than
accepting a Pass and querying it for analyses.

This is necessary to allow the utilities to work both with the old and
new pass managers, and I also think this makes the interface much more
clear and helps the reader know what analyses the utility can actually
handle. I plan to repeat this process iteratively to clean up all the
pass utilities.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226386 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-18 01:45:07 +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
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
Kostya Serebryany
f82e60f03d Introduce llvm::SplitAllCriticalEdges
Summary:
move the code from BreakCriticalEdges::runOnFunction()
into a separate utility function llvm::SplitAllCriticalEdges()
so that it can be used independently.
No functionality change intended.

Test Plan: check-llvm

Reviewers: nlewycky

Reviewed By: nlewycky

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6313

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222288 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-19 00:17:31 +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
Peter Collingbourne
ca3c5b8722 Give SplitBlockAndInsertIfThen the ability to update a domtree.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213045 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-15 04:40:27 +00:00
Chandler Carruth
55eab086e3 Fix rampant quadratic behavior in UpdatePHINodes. The operation of
mapping from a basic block to an incoming value, either for removal or
just lookup, is linear in the number of predecessors, and we were doing
this for every entry in the 'Preds' list which is in many cases almost
all of them!

Unfortunately, the fixes are quite ugly. PHI nodes just don't make this
operation easy. The efficient way to fix this is to have a clever
'remove_if' operation on PHI nodes that lets us do a single pass over
all the incoming values of the original PHI node, extracting the ones we
care about. Then we could quickly construct the new phi node from this
list. This would remove the remaining underlying quadratic movement of
unrelated incoming values and the need for silly backwards looping to
"minimize" how often we hit the quadratic case.

This is the last obvious fix for PR19499. It shaves another 20% off the
compile time for me, and while UpdatePHINodes remains in the profile,
most of the time is now stemming from the well known inefficiencies of
LVI and jump threading.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207409 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 10:37:30 +00:00
Craig Topper
c34a25d59d [C++] Use 'nullptr'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207394 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 04:05:08 +00:00
Craig Topper
8d7221ccf5 [C++] Use 'nullptr'. Transforms edition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207196 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-25 05:29:35 +00:00
Evgeniy Stepanov
eef411a52a Set debug info for instructions inserted in SplitBlockAndInsertIfThen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204230 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-19 12:56:38 +00:00
Chandler Carruth
eb3d76da81 [Modules] Move ValueHandle into the IR library where Value itself lives.
Move the test for this class into the IR unittests as well.

This uncovers that ValueMap too is in the IR library. Ironically, the
unittest for ValueMap is useless in the Support library (honestly, so
was the ValueHandle test) and so it already lives in the IR unittests.
Mmmm, tasty layering.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202821 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-04 11:17:44 +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
Kostya Serebryany
26f1d1cbbc [asan] don't unpoison redzones on function exit in use-after-return mode.
Summary:
Before this change the instrumented code before Ret instructions looked like:
  <Unpoison Frame Redzones>
  if (Frame != OriginalFrame) // I.e. Frame is fake
     <Poison Complete Frame>

Now the instrumented code looks like:
  if (Frame != OriginalFrame) // I.e. Frame is fake
     <Poison Complete Frame>
  else
     <Unpoison Frame Redzones>

Reviewers: eugenis

Reviewed By: eugenis

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D2458

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197907 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-23 14:15:08 +00:00