Commit Graph

12603 Commits

Author SHA1 Message Date
Andrew Kaylor f22fe4ae18 Remap frame variables for native Windows exception handling.
Differential Revision: http://reviews.llvm.org/D7770

llvm-svn: 230249
2015-02-23 20:01:56 +00:00
Chad Rosier 543900539f Prevent hoisting fmul from THEN/ELSE to IF if there is fmsub/fmadd opportunity.
This patch adds the isProfitableToHoist API.  For AArch64, we want to prevent a
fmul from being hoisted in cases where it is more profitable to form a
fmsub/fmadd.

Phabricator Review: http://reviews.llvm.org/D7299
Patch by Lawrence Hu <lawrence@codeaurora.org>

llvm-svn: 230241
2015-02-23 19:15:16 +00:00
Mehdi Amini cd3ca6f7dd InstSimplify: simplify 0 / X if nnan and nsz
From: Fiona Glaser <fglaser@apple.com>
llvm-svn: 230238
2015-02-23 18:30:25 +00:00
David Blaikie 5e5d7840fb Roll condition into an assert then wrap it 'ifndef NDEBUG' to protect from the inevitable "unused variable" warning in a non-asserts build.
llvm-svn: 230181
2015-02-22 20:58:38 +00:00
Hal Finkel 3d4269ab05 [LICM] Refactor to expose functionality as utility functions
This refactors the core functionality of LICM: HoistRegion, SinkRegion and
PromoteAliasSet (renamed to promoteLoopAccessesToScalars) as utility functions
in LoopUtils. This will enable other transformations to make use of them
directly.

Patch by Ashutosh Nema.

llvm-svn: 230178
2015-02-22 18:35:32 +00:00
NAKAMURA Takumi f7d08f6dcc RewriteStatepointsForGC.cpp: Fix for -Asserts to mark isNullConstant() as LLVM_ATTRIBUTE_UNUSED. [-Wunused-function]
llvm-svn: 230169
2015-02-22 09:58:19 +00:00
NAKAMURA Takumi 02aa295a00 RewriteStatepointsForGC.cpp: Fix for -Asserts. [-Wunused-variable]
llvm-svn: 230168
2015-02-22 09:58:13 +00:00
NAKAMURA Takumi 6c24684c95 LowerBitSets.cpp: Prune incorrect \param(s). [-Wdocumentation]
\param should be used as itemized.

llvm-svn: 230167
2015-02-22 09:51:42 +00:00
Sanjoy Das 95c476db94 IRCE: generalize InductiveRangeCheck::computeSafeIterationSpace to
work with a non-canonical induction variable.

This is currently a non-functional change because we only ever call
computeSafeIterationSpace on a canonical induction variable; but the
generalization will be useful in a later commit.

llvm-svn: 230151
2015-02-21 22:20:22 +00:00
Sanjoy Das 7fc60da2f5 IRCE: use SCEVs instead of llvm::Value's for intermediate
calculations.  Semantically non-functional change.

This gets rid of some of the SCEV -> Value -> SCEV round tripping and
the Construct(SMin|SMax)Of and MaybeSimplify helper routines.

llvm-svn: 230150
2015-02-21 22:07:32 +00:00
Philip Reames 0b1b387441 [PlaceSafepoints] Adjust enablement logic to default to off and be GC configurable per GC
Previously, this pass ran over every function in the Module if added to the pass order.  With this change, it runs only over those with a GC attribute where the GC explicitly opts in.  A GC can also choose which of entry safepoint polls, backedge safepoint polls, and call safepoints it wants.  I hope to get these exposed as checks on the GCStrategy at some point, but for now, the checks are manual string comparisons.

llvm-svn: 230097
2015-02-21 00:09:09 +00:00
David Blaikie 82ad78771b Remove some unnecessary unreachables in favor of (sometimes implicit) assertions
Also simplify some else-after-return cases including some standard
algorithm convenience/use.

llvm-svn: 230094
2015-02-20 23:44:24 +00:00
Philip Reames 1f3e5c195c Hide a bunch of advanced testing options in default opt --help output
These are internal options.  I need to go through, evaluate which are worth keeping and which not.  Many of them should probably be renamed as well.  Until I have time to do that, we can at least stop poluting the standard opt -help output.

llvm-svn: 230088
2015-02-20 23:32:03 +00:00
Philip Reames 1f017547bb [RewriteStatepointsForGC] Use DenseSet in place of std::set [NFC]
This should be the last cleanup on non-llvm preferred data structures.  I left one use of std::set in an assertion; DenseSet didn't seem to have a tombstone for CallSite defined.  That might be worth fixing, but wasn't worth it for a debug only use.

llvm-svn: 230084
2015-02-20 23:16:52 +00:00
Philip Reames e9c3b9bd46 [RewriteStatepointsForGC] Replace std::map with DenseMap
I'd done the work of extracting the typedef in a previous commit, but didn't actually change it.  Hopefully this will make any subtle changes easier to isolate.

llvm-svn: 230081
2015-02-20 22:48:20 +00:00
Philip Reames d2b664642f [RewriteStatepointsForGC] Cleanup - replace std::vector usage [NFC]
Migrate std::vector usage to a combination of SmallVector and ArrayRef.

llvm-svn: 230079
2015-02-20 22:39:41 +00:00
Philip Reames 860660ea5e [RewriteStatepointsForGC] More style cleanup [NFC]
Use llvm_unreachable where appropriate, use SmallVector where easy to do so, introduce typedefs for planned type migrations.

llvm-svn: 230068
2015-02-20 22:05:18 +00:00
Philip Reames 0a3240f4de [RewriteStatepointsForGC] Remove notion of SafepointBounds [NFC]
The notion of a range of inserted safepoint related code is no longer really applicable.  This survived over from an earlier implementation.  Just saving the inserted gc.statepoint and working from that is far clearer given the current code structure.  Particularly when invokable statepoints get involved.

llvm-svn: 230063
2015-02-20 21:34:11 +00:00
Benjamin Kramer 911d5b3ace LoopRotate: When reconstructing loop simplify form don't split edges from indirectbrs.
Yet another chapter in the endless story. While this looks like we leave
the loop in a non-canonical state this replicates the logic in
LoopSimplify so it doesn't diverge from the canonical form in any way.

PR21968

llvm-svn: 230058
2015-02-20 20:49:25 +00:00
Peter Collingbourne e6909c8e8b Introduce bitset metadata format and bitset lowering pass.
This patch introduces a new mechanism that allows IR modules to co-operatively
build pointer sets corresponding to addresses within a given set of
globals. One particular use case for this is to allow a C++ program to
efficiently verify (at each call site) that a vtable pointer is in the set
of valid vtable pointers for the class or its derived classes. One way of
doing this is for a toolchain component to build, for each class, a bit set
that maps to the memory region allocated for the vtables, such that each 1
bit in the bit set maps to a valid vtable for that class, and lay out the
vtables next to each other, to minimize the total size of the bit sets.

The patch introduces a metadata format for representing pointer sets, an
'@llvm.bitset.test' intrinsic and an LTO lowering pass that lays out the globals
and builds the bitsets, and documents the new feature.

Differential Revision: http://reviews.llvm.org/D7288

llvm-svn: 230054
2015-02-20 20:30:47 +00:00
Philip Reames fa2fcf173b [GC, RewriteStatepointsForGC] Style cleanup and bug fix
When doing style cleanup, I noticed a minor bug in this code.  If we have a pointer that we think is unused after a statepoint and thus doesn't need relocation, we store a null pointer into the alloca we're about to promote.  This helps turn a mistake in liveness analysis into an easily debuggable crash.  It turned out this code had never been updated to handle invoke statepoints.  

There's no test for this.  Without a bug in liveness, it appears impossible to make this trigger in a way which is visible in the resulting IR.  We might store the null, but when promoting the alloca, there will be no uses and thus nothing to test against.  Suggestions on how to test are very welcome.

llvm-svn: 230047
2015-02-20 19:51:56 +00:00
Reid Kleckner a070ee5ef5 Use unreachable instead of assert(false) to silence MSVC warning
llvm-svn: 230045
2015-02-20 19:46:02 +00:00
Philip Reames f20413245a [GC] Style cleanup for RewriteStatepointForGC (1 of many) [NFC]
Starting to update variable naming and types to match LLVM style.  This will be an incremental process to minimize the chance of breakage as I work.  Step one, rename member variables to LLVM CamelCase and use llvm's ADT.  Much more to come.

llvm-svn: 230042
2015-02-20 19:26:04 +00:00
Philip Reames 2ef029c7ae Bugfix for 229954
Before calling Function::getGC to test for enablement, we need to make sure there's actually a GC at all via Function::hasGC.  Otherwise, we'd crash on functions without a GC.  Thankfully, this only mattered if you manually scheduled the pass, but still, oops. :(

llvm-svn: 230040
2015-02-20 18:56:14 +00:00
Benjamin Kramer 6f66545ae6 RewriteStatepointsForGC: Move details into anonymous namespaces. NFC.
While there reduce the number of duplicated std::map lookups.

llvm-svn: 230012
2015-02-20 14:00:58 +00:00
Benjamin Kramer d4a3a55564 Wrap recursive function only used in assert in #ifndef NDEBUG.
Avoids unused function warnings in Release builds.

llvm-svn: 230009
2015-02-20 13:15:49 +00:00
Nick Lewycky eb3231eefa Fix build in release mode, four cases of -Wunused-variable.
llvm-svn: 229976
2015-02-20 07:14:02 +00:00
Hal Finkel 847e05f569 [InstCombine] Remove unnecessary variable indexing into single-element arrays
This change addresses a deficiency pointed out in PR22629. To copy from the bug
report:

[from the bug report]

Consider this code:

int f(int x) {
  int a[] = {12};
  return a[x];
}

GCC knows to optimize this to

movl     $12, %eax
ret

The code generated by recent Clang at -O3 is:

movslq   %edi, %rax
movl     .L_ZZ1fiE1a(,%rax,4), %eax
retq

.L_ZZ1fiE1a:
  .long    12                      # 0xc

[end from the bug report]

This definitely seems worth fixing. I've also seen this kind of code before (as
the base case of generic vector wrapper templates with one element).

The general idea is to look at the GEP feeding a load or a store, which has
some variable as its first non-zero index, and determine if that index must be
zero (or else an out-of-bounds access would occur). We can do this for allocas
and globals with constant initializers where we know the maximum size of the
underlying object. When we find such a GEP, we create a new one for the memory
access with that first variable index replaced with a constant zero.

Even if we can't eliminate the memory access (and sometimes we can't), it is
still useful because it removes unnecessary indexing calculations.

llvm-svn: 229959
2015-02-20 03:05:53 +00:00
Philip Reames 6faacf4772 Adjust enablement of RewriteStatepointsForGC
When back merging the changes in 229945 I noticed that I forgot to mark the test cases with the appropriate GC.  We want the rewriting to be off by default (even when manually added to the pass order), not on-by default.  To keep the current test working, mark them as using the statepoint-example GC and whitelist that GC.  

Longer term, we need a better selection mechanism here for both actual usage and testing.  As I migrate more tests to the in tree version of this pass, I will probably need to update the enable/disable logic as well. 

llvm-svn: 229954
2015-02-20 02:34:49 +00:00
Philip Reames d16a9b1fdc Add a pass for constructing gc.statepoint sequences w/explicit relocations
This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'.

This patch is setting the stage for work to continue in tree.  In particular, there are known naming and style violations in the current patch.  I'll try to get those resolved over the next week or so.  As I touch each area to make style changes, I need to make sure we have adequate testing in place.  As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage.

The pass has several main subproblems it needs to address:
- First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future.  Note that the current change doesn't actually contain a useful liveness analysis.  It was seperated into a followup change as the code wasn't ready to be shared.  Instead, the current implementation just considers any dominating def of appropriate pointer type to be live.
- Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. 
- Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us.

llvm-svn: 229945
2015-02-20 01:06:44 +00:00
Kostya Serebryany 885994618c [sanitizer] when dumping the basic block trace, also dump the module names. Patch by Laszlo Szekeres
llvm-svn: 229940
2015-02-20 00:30:44 +00:00
Michael Gottesman 0fc2accb58 [objc-arc-contract] We can not move retains over instructions which can not conservatively be proven to not decrement the retain's RCIdentity.
I also cleaned up the code to make it more understandable for mere mortals.

<rdar://problem/19853758>

llvm-svn: 229937
2015-02-20 00:02:49 +00:00
Michael Gottesman 5ab64de62b [objc-arc] Add the predicate CanDecrementRefCount.
This is different from CanAlterRefCount since CanDecrementRefCount is
attempting to prove specifically whether or not an instruction can
decrement instead of the more general question of whether it can
decrement or increment.

llvm-svn: 229936
2015-02-20 00:02:45 +00:00
Benjamin Kramer dfedfeb298 SSAUpdater: Use range-based for. NFC.
llvm-svn: 229908
2015-02-19 20:04:02 +00:00
Michael Gottesman 2e0e4e07b4 [objc-arc] Convert the bodies of ARCInstKind predicates into covered switches.
This is much better than the previous manner of just using
short-curcuiting booleans from:

1. A "naive" efficiency perspective: we do not have to rely on the
compiler to change the short circuiting boolean operations into a
switch.
2. An understanding perspective by making the implicit behavior of
negative predicates explicit.
3. A maintainability perspective through the covered switch flag making
it easy to know where to update code when adding new ARCInstKinds.

llvm-svn: 229906
2015-02-19 19:51:36 +00:00
Michael Gottesman 6f729fa675 [objc-arc] Change the InstructionClass to be an enum class called ARCInstKind.
I also renamed ObjCARCUtil.cpp -> ARCInstKind.cpp. That file only contained
items related to ARCInstKind anyways.

llvm-svn: 229905
2015-02-19 19:51:32 +00:00
Adam Nemet 57ac766ee9 [LoopAccesses] Change LAA:getInfo to return a constant reference
As expected, this required a few more const-correctness fixes.

Based on Hal's feedback on D7684.

llvm-svn: 229899
2015-02-19 19:15:21 +00:00
Adam Nemet 2bd6e984ef [LoopAccesses] Split out LoopAccessReport from VectorizerReport
The only difference between these two is that VectorizerReport adds a
vectorizer-specific prefix to its messages.  When LAA is used in the
vectorizer context the prefix is added when we promote the
LoopAccessReport into a VectorizerReport via one of the constructors.

This is part of the patchset that converts LoopAccessAnalysis into an
actual analysis pass.

llvm-svn: 229897
2015-02-19 19:15:15 +00:00
Adam Nemet 3e87634fd8 [LoopAccesses] Add missing const to APIs in VectorizationReport
When I split out LoopAccessReport from this, I need to create some temps
so constness becomes necessary.

This is part of the patchset that converts LoopAccessAnalysis into an
actual analysis pass.

llvm-svn: 229896
2015-02-19 19:15:13 +00:00
Adam Nemet 339f42b396 [LoopAccesses] Change debug messages from LV to LAA
Also add pass name as an argument to VectorizationReport::emitAnalysis.

This is part of the patchset that converts LoopAccessAnalysis into an
actual analysis pass.

llvm-svn: 229894
2015-02-19 19:15:07 +00:00
Adam Nemet 3bfd93d789 [LoopAccesses] Create the analysis pass
This is a function pass that runs the analysis on demand.  The analysis
can be initiated by querying the loop access info via LAA::getInfo.  It
either returns the cached info or runs the analysis.

Symbolic stride information continues to reside outside of this analysis
pass. We may move it inside later but it's not a priority for me right
now.  The idea is that Loop Distribution won't support run-time stride
checking at least initially.

This means that when querying the analysis, symbolic stride information
can be provided optionally.  Whether stride information is used can
invalidate the cache entry and rerun the analysis.  Note that if the
loop does not have any symbolic stride, the entry should be preserved
across Loop Distribution and LV.

Since currently the only user of the pass is LV, I just check that the
symbolic stride information didn't change when using a cached result.

On the LV side, LoopVectorizationLegality requests the info object
corresponding to the loop from the analysis pass.  A large chunk of the
diff is due to LAI becoming a pointer from a reference.

A test will be added as part of the -analyze patch.

Also tested that with AVX, we generate identical assembly output for the
testsuite (including the external testsuite) before and after.

This is part of the patchset that converts LoopAccessAnalysis into an
actual analysis pass.

llvm-svn: 229893
2015-02-19 19:15:04 +00:00
Adam Nemet 436018c3ff [LoopAccesses] Cache the result of canVectorizeMemory
LAA will be an on-demand analysis pass, so we need to cache the result
of the analysis.  canVectorizeMemory is renamed to analyzeLoop which
computes the result.  canVectorizeMemory becomes the query function for
the cached result.

This is part of the patchset that converts LoopAccessAnalysis into an
actual analysis pass.

llvm-svn: 229892
2015-02-19 19:15:00 +00:00
Adam Nemet c922853b93 [LoopAccesses] Stash the report from the analysis rather than emitting it
The transformation passes will query this and then emit them as part of
their own report.  The currently only user LV is modified to do just
that.

This is part of the patchset that converts LoopAccessAnalysis into an
actual analysis pass.

llvm-svn: 229891
2015-02-19 19:14:56 +00:00
Adam Nemet f219c64723 [LoopAccesses] Make VectorizerParams global + fix for cyclic dep
As LAA is becoming a pass, we can no longer pass the params to its
constructor.  This changes the command line flags to have external
storage.  These can now be accessed both from LV and LAA.

VectorizerParams is moved out of LoopAccessInfo in order to shorten the
code to access it.

This commits also has the fix (D7731) to the break dependence cycle
between the analysis and vector libraries.

This is part of the patchset that converts LoopAccessAnalysis into an
actual analysis pass.

llvm-svn: 229890
2015-02-19 19:14:52 +00:00
Adam Nemet 04d4163e95 Revert "Reformat."
This reverts commit r229651.

I'd like to ultimately revert r229650 but this reformat stands in the
way.  I'll reformat the affected files once the the loop-access pass is
fully committed.

llvm-svn: 229889
2015-02-19 19:14:34 +00:00
Benjamin Kramer 1c2beed7fd LSR: Move set instead of copying. NFC.
llvm-svn: 229871
2015-02-19 17:19:43 +00:00
Benjamin Kramer ea68a944a1 Demote vectors to arrays. No functionality change.
llvm-svn: 229861
2015-02-19 15:26:17 +00:00
Michael Gottesman e5ad66f8a9 [objc-arc] Introduce the concept of RCIdentity and rename all relevant functions to use that name. NFC.
The RCIdentity root ("Reference Count Identity Root") of a value V is a
dominating value U for which retaining or releasing U is equivalent to
retaining or releasing V. In other words, ARC operations on V are
equivalent to ARC operations on U.

This is a useful property to ascertain since we can use this in the ARC
optimizer to make it easier to match up ARC operations by always mapping
ARC operations to RCIdentityRoots instead of pointers themselves. Then
we perform pairing of retains, releases which are applied to the same
RCIdentityRoot.

In general, the two ways that we see RCIdentical values in ObjC are via:

  1. PointerCasts
  2. Forwarding Calls that return their argument verbatim.

As such in ObjC, two RCIdentical pointers must always point to the same
memory location.

Previously this concept was implicit in the code and various methods
that dealt with this concept were given functional names that did not
conform to any name in the "ARC" model. This often times resulted in
code that was hard for the non-ARC acquanted to understand resulting in
unhappiness and confusion.

llvm-svn: 229796
2015-02-19 00:42:38 +00:00
Michael Gottesman dfa3e4b08a [objc-arc-contract] Rename contractRelease => tryToContractReleaseIntoStoreStrong.
NFC. Makes it clearer what this method is actually supposed to do.

llvm-svn: 229795
2015-02-19 00:42:34 +00:00
Michael Gottesman 1827973f80 [objc-arc-contract] Refactor out tryToPeepholeInstruction into its own method. NFC.
The main method of ObjCARCContract is really large and busy. By refactoring this
out, it becomes easier to reason about.

llvm-svn: 229794
2015-02-19 00:42:30 +00:00