This should fix some compile-time regressions after r267672.  Thanks to
Chris Matthews for bisecting it.

llvm-svn: 269392

We only really need this to be true for SIFixSGPRCopies.
I'm not sure there's any way this could happen before that point.

Fixes a case where MachineCSE could introduce a cross block
scc use.

llvm-svn: 269391

a sequence of values.

It increments through the values in the half-open range: [Begin, End),
producing those values when indirecting the iterator. It should support
integers, iterators, and any other type providing these basic arithmetic
operations.

This came up in the C++ standards committee meeting, and it seemed like
a useful construct that LLVM might want as well, and I wanted to
understand how easily we could solve it. I suspect this can be used to
write simpler counting loops even in LLVM along the lines of:

  for (int i : seq(0, v.size())) {
    ...
  };

As part of this, I had to fix the lack of a proxy object returned from
the operator[] in our iterator facade.

Differential Revision: http://reviews.llvm.org/D17870

llvm-svn: 269390

[clang-tidy] - PerformanceUnnecesaryCopyInitialization - only trigger for decl stmts with single VarDecl.

Summary: This fixes bug: https://llvm.org/bugs/show_bug.cgi?id=27325

Reviewers: alexfh

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D19865

llvm-svn: 269389

[Unroll] Implement a conservative and monotonically increasing cost tracking system during the full unroll heuristic analysis that avoids counting any instruction cost until that instruction becomes "live" through a side-effect or use outside the...

Summary:
...loop after the last iteration.

This is really hard to do correctly. The core problem is that we need to
model liveness through the induction PHIs from iteration to iteration in
order to get the correct results, and we need to correctly de-duplicate
the common subgraphs of instructions feeding some subset of the
induction PHIs. All of this can be driven either from a side effect at
some iteration or from the loop values used after the loop finishes.

This patch implements this by storing the forward-propagating analysis
of each instruction in a cache to recall whether it was free and whether
it has become live and thus counted toward the total unroll cost. Then,
at each sink for a value in the loop, we recursively walk back through
every value that feeds the sink, including looping back through the
iterations as needed, until we have marked the entire input graph as
live. Because we cache this, we never visit instructions more than twice
-- once when we analyze them and put them into the cache, and once when
we count their cost towards the unrolled loop. Also, because the cache
is only two bits and because we are dealing with relatively small
iteration counts, we can store all of this very densely in memory to
avoid this from becoming an excessively slow analysis.

The code here is still pretty gross. I would appreciate suggestions
about better ways to factor or split this up, I've stared too long at
the algorithmic side to really have a good sense of what the design
should probably look at.

Also, it might seem like we should do all of this bottom-up, but I think
that is a red herring. Specifically, the simplification power is *much*
greater working top-down. We can forward propagate very effectively,
even across strange and interesting recurrances around the backedge.
Because we use data to propagate, this doesn't cause a state space
explosion. Doing this level of constant folding, etc, would be very
expensive to do bottom-up because it wouldn't be until the last moment
that you could collapse everything. The current solution is essentially
a top-down simplification with a bottom-up cost accounting which seems
to get the best of both worlds. It makes the simplification incremental
and powerful while leaving everything dead until we *know* it is needed.

Finally, a core property of this approach is its *monotonicity*. At all
times, the current UnrolledCost is a conservatively low estimate. This
ensures that we will never early-exit from the analysis due to exceeding
a threshold when if we had continued, the cost would have gone back
below the threshold. These kinds of bugs can cause incredibly hard to
track down random changes to behavior.

We could use a techinque similar (but much simpler) within the inliner
as well to avoid considering speculated code in the inline cost.

Reviewers: chandlerc

Subscribers: sanjoy, mzolotukhin, llvm-commits

Differential Revision: http://reviews.llvm.org/D11758

llvm-svn: 269388

Summary:
Currently we consider such instructions as simplified, which is incorrect,
because if their user isn't simplified, we can't actually simplify them too.
This biases our estimates of profitability: for instance the analyzer expects
much more gains from unrolling memcpy loops than there actually are.

Reviewers: hfinkel, chandlerc

Subscribers: mzolotukhin, llvm-commits

Differential Revision: http://reviews.llvm.org/D17365

llvm-svn: 269387

This change is the gold side of the change made in D17115 and clang
patch r261045 to add a ThinLTO specific pipeline that moves more of
the optimization to the backends.

llvm-svn: 269386

clang asserts when compiling the following code because r231508 made
changes to promote constant temporary arrays and records to globals
with constant initializers:

std::vector<NSString*> strs = {@"a", @"b"};

This commit changes the code to return early if the object returned by
createReferenceTemporary is a global variable with an initializer.

rdar://problem/25504992
rdar://problem/25955179

Differential Revision: http://reviews.llvm.org/D20045

llvm-svn: 269385

llvm-svn: 269384

In verbose mode, we emit a warning if the DWOId of a skeleton CU
mismatches the DWOId of the referenced module. This patch updates the
cached DWOId after a module has been loaded to the DWOId of the module
on disk (instead of storing the DWOId we expected to load). This
allows us to correctly emit the mismatch warning for all subsequent
object files that want to import the same module. This patch also
ensures both warnings are only emitted in verbose mode.

rdar://problem/26214027

llvm-svn: 269383

functionality change; this information is not yet in use.

llvm-svn: 269382

llvm-svn: 269381

Having the MachO enums in a def file instead of inline will allow us to write utilities and encoding/decoding methods for load commands without having to write a lot of mechanically repeated code.

llvm-svn: 269380

This one has a lot of code churn, but it's all mechanical and
straightforward.

- Where we were returning a node before, call ReplaceNode instead.
- Where we would return null to fall back to another selector, rename
  the method to try* and return a bool for success.
- Where we were calling SelectNodeTo, just return afterwards.

Part of llvm.org/pr26808.

llvm-svn: 269379

<rdar://problem/26207478>

llvm-svn: 269378

The main issues were:
- Listeners recently were converted over to used by getting a shared pointer to a listener. And when they listened to broadcasters they would get a strong reference added to them meaning the listeners would never go away. This caused memory usage to increase and would cause performance issue if many steps were done.
- The lldb_private::Process private state thread had an issue where if a "stop" contol signal was attempted to be sent to that thread, it could end up not responding in 2 seconds and end up getting cancelled which might cause us to cancel a thread that had a mutex locked and it would deadlock the test.

This change makes broadcasters hold onto weak references to listeners. It also fixes some bad threading code that had races inside of it by making the m_events_mutex be non-recursive and getting rid of fragile use of a Predicate<bool> to say that new events are available, and replacing it with using the m_events_mutex with a new m_events_condition to control access to the events in a safer way.

The private state thread now uses a safer way to communicate that the control event has been received by the private state thread: it makes a EventDataReceipt instance that it attaches to the event that sends the control to the private state thread and used this to synchronize the fact that the private state thread has received the event instead of using a Predicate<bool> to convey the info. When the signal event is received, it will pull the event off of the queue in the private state thread and cause the EventData::DoOnRemoval() to be called, which will signal that the event has been received. This cleans up the signal delivery notification so it doesn't rely on a member variable of the process class to convey the info.

std::shared_ptr<EventDataReceipt> event_receipt_sp(new EventDataReceipt());
m_private_state_control_broadcaster.BroadcastEvent(signal, event_receipt_sp);

<rdar://problem/26256353> Listeners are being kept around longer than they should be due to recent changs
<rdar://problem/26256258> Private process state thread can be cancelled and cause deadlocks in test suite

llvm-svn: 269377

llvm-svn: 269376

The first part handles whatever has to be written to the r_offset
position.

The second part handles creating got and plt entries.

llvm-svn: 269375

Also stop visiting type records when we encounter an error.

llvm-svn: 269374

<rdar://problem/26256049>

llvm-svn: 269373

The adding of <atomic> to test_common.h broke 12 tests on Darwin. We work around this by not including <atomic> when building on darwin for libstdc++ tests.

llvm-svn: 269372

Reduce space in empty constructors and between data members and first public section.

Fix some Include What You Use warnings.

Differential revision: http://reviews.llvm.org/D20213

llvm-svn: 269371

Ported DA to the new PM by splitting the former DependenceAnalysis Pass
into a DependenceInfo result type and DependenceAnalysisWrapperPass type
and adding a new PM-style DependenceAnalysis analysis pass returning the
DependenceInfo.

Patch by Philip Pfaffe, most of the review by Justin.

Differential Revision: http://reviews.llvm.org/D18834

llvm-svn: 269370

llvm-svn: 269369

Dynamic table when printed shows uppercase tag/values.
This changes it to lower case when printing in GNU style

llvm-svn: 269368

Refactor constant expression evaluation of CXXConstructExpr to reduce duplication between array and class initialization.

llvm-svn: 269367

llvm-svn: 269366

This change adds a new entry point,
kmp_aligned_malloc(size_t size, size_t alignment), an entry point corresponding
to kmp_malloc() but with the capability to return aligned memory as well.
Other allocator routines have been adjusted so that kmp_free() can be used for
freeing memory blocks allocated by any kmp_*alloc() routine, including the new
kmp_aligned_malloc() routine.

Differential Revision: http://reviews.llvm.org/D19814

llvm-svn: 269365

- Where we were returning a node before, call ReplaceNode instead.
- Where we were calling SelectNodeTo, just return afterwards.

Part of llvm.org/pr26808.

llvm-svn: 269364

After hot teams were enabled by default, the library started using levels kept
in the team structure. The levels are broken in case foreign thread exits and
puts its team into the pool which is then re-used by another foreign thread.
The broken behavior observed is when printing the levels for each new team, one
gets 1, 2, 1, 2, 1, 2, etc. This makes the library believe that every other
team is nested which is incorrect. What is wanted is for the levels to be
1, 1, 1, etc.

Differential Revision: http://reviews.llvm.org/D19980

llvm-svn: 269363

This is similar to the other changes this function does. With this all
Relocations.push_back calls look similar.

llvm-svn: 269362

I will commit again with a fixed commit message.

llvm-svn: 269361

This is similar to the other changes this function does. With this all
Relocations.push_back calls look similar.

llvm-svn: 269360

llvm-svn: 269359

- Where we were returning a node before, call ReplaceNode instead.
- Where we had already replaced all uses and we returned a node, just
  remove the dead node instead.
- Where we would return null to fall back to another selector, rename
  the method to try* and return a bool for success.

Part of llvm.org/pr26808.

llvm-svn: 269358

Move runtime specific code from the common header file
to runtime source.

llvm-svn: 269357

llvm-svn: 269356

When we convert to the void Select interface, leaving unreferenced
nodes around won't be allowed anymore.

Part of llvm.org/pr26808.

llvm-svn: 269355

This change implements the transformation in processInstruction() for the
LDR rt, =expression to MOV rt, expression when the expression can be evaluated
and can fit into the immediate field of the MOV or a MVN.

Across the ARM and Thumb instruction sets there are several cases to consider,
each with a different range of representatble constants.

In ARM we have:
 * Modified immediate (All ARM architectures)
 * MOVW (v6t2 and above)

In Thumb we have:
 * Modified immediate (v6t2, v7m and v8m.mainline)
 * MOVW (v6t2, v7m, v8.mainline and v8m.baseline)
 * Narrow Thumb MOV that can be used in an IT block (non flag-setting)

If the immediate fits any of the available alternatives then we make the transformation.

Fixes 25722.

Patch by Peter Smith.

llvm-svn: 269354

Alter instances in the test-suite that use immediates that can be represented
in the immediate field of a MOV. The reason for doing this is that when the
LDR rt,=imm transformation to MOV rt, imm the existing tests do not need to
be modified.

Required by the patch that fixes PR25722.

Patch by Peter Smith.

llvm-svn: 269353