Commit Graph

1155 Commits

Author SHA1 Message Date
Philip Reames
76ebd15437 [GC] improve testing around gc.relocate and fix a test
Patch by: Ramkumar Ramachandra <artagnon@gmail.com>

"This patch started out as an exploration of gc.relocate, and an attempt
to write a simple test in call-lowering. I then noticed that the
arguments of gc.relocate were not checked fully, so I went in and fixed
a few things. Finally, the most important outcome of this patch is that
my new error handling code caught a bug in a callsite in
stackmap-format."

Differential Revision: http://reviews.llvm.org/D6824

llvm-svn: 225412
2015-01-07 22:48:01 +00:00
Duncan P. N. Exon Smith
5e5b85098d IR: Add MDNode::getDistinct()
Allow distinct `MDNode`s to be explicitly created.  There's no way (yet)
of representing their distinctness in assembly/bitcode, however, so this
still isn't first-class.

Part of PR22111.

llvm-svn: 225406
2015-01-07 22:24:46 +00:00
Duncan P. N. Exon Smith
df55d8ba83 Linker: Don't use MDNode::replaceOperandWith()
`MDNode::replaceOperandWith()` changes all instances of metadata.  Stop
using it when linking module flags, since (due to uniquing) the flag
values could be used by other metadata.

Instead, use new API `NamedMDNode::setOperand()` to update the reference
directly.

llvm-svn: 225397
2015-01-07 21:32:27 +00:00
Chandler Carruth
fdb4180514 [PM] Fix a pretty nasty bug where the new pass manager would invalidate
passes too many time.

I think this is actually the issue that someone raised with me at the
developer's meeting and in an email, but that we never really got to the
bottom of. Having all the testing utilities made it much easier to dig
down and uncover the core issue.

When a pass manager is running many passes over a single function, we
need it to invalidate the analyses between each run so that they can be
re-computed as needed. We also need to track the intersection of
preserved higher-level analyses across all the passes that we run (for
example, if there is one module analysis which all the function analyses
preserve, we want to track that and propagate it). Unfortunately, this
interacted poorly with any enclosing pass adaptor between two IR units.
It would see the intersection of preserved analyses, and need to
invalidate any other analyses, but some of the un-preserved analyses
might have already been invalidated *and recomputed*! We would fail to
propagate the fact that the analysis had already been invalidated.

The solution to this struck me as really strange at first, but the more
I thought about it, the more natural it seemed. After a nice discussion
with Duncan about it on IRC, it seemed even nicer. The idea is that
invalidating an analysis *causes* it to be preserved! Preserving the
lack of result is trivial. If it is recomputed, great. Until something
*else* invalidates it again, we're good.

The consequence of this is that the invalidate methods on the analysis
manager which operate over many passes now consume their
PreservedAnalyses object, update it to "preserve" every analysis pass to
which it delivers an invalidation (regardless of whether the pass
chooses to be removed, or handles the invalidation itself by updating
itself). Then we return this augmented set from the invalidate routine,
letting the pass manager take the result and use the intersection of
*that* across each pass run to compute the final preserved set. This
accounts for all the places where the early invalidation of an analysis
has already "preserved" it for a future run.

I've beefed up the testing and adjusted the assertions to show that we
no longer repeatedly invalidate or compute the analyses across nested
pass managers.

llvm-svn: 225333
2015-01-07 01:58:35 +00:00
Rafael Espindola
83a362cde8 Change the .ll syntax for comdats and add a syntactic sugar.
In order to make comdats always explicit in the IR, we decided to make
the syntax a bit more compact for the case of a GlobalObject in a
comdat with the same name.

Just dropping the $name causes problems for

@foo = globabl i32 0, comdat
$bar = comdat ...

and

declare void @foo() comdat
$bar = comdat ...

So the syntax is changed to

@g1 = globabl i32 0, comdat($c1)
@g2 = globabl i32 0, comdat

and

declare void @foo() comdat($c1)
declare void @foo() comdat

llvm-svn: 225302
2015-01-06 22:55:16 +00:00
Chandler Carruth
3472ffb37e [PM] Add a utility pass template that synthesizes the invalidation of
a specific analysis result.

This is quite handy to test things, and will also likely be very useful
for debugging issues. You could narrow down pass validation failures by
walking these invalidate pass runs up and down the pass pipeline, etc.
I've added support to the pass pipeline parsing to be able to create one
of these for any analysis pass desired.

Just adding this class uncovered one latent bug where the
AnalysisManager CRTP base class had a hard-coded Module type rather than
using IRUnitT.

I've also added tests for invalidation and caching of analyses in
a basic way across all the pass managers. These in turn uncovered two
more bugs where we failed to correctly invalidate an analysis -- its
results were invalidated but the key for re-running the pass was never
cleared and so it was never re-run. Quite nasty. I'm very glad to debug
this here rather than with a full system.

Also, yes, the naming here is horrid. I'm going to update some of the
names to be slightly less awful shortly. But really, I've no "good"
ideas for naming. I'll be satisfied if I can get it to "not bad".

llvm-svn: 225246
2015-01-06 04:49:44 +00:00
Duncan P. N. Exon Smith
bcd960a1bc IR: Don't drop MDNode uniquing on null operands
Now that `LLVMContextImpl` can call `MDNode::dropAllReferences()` to
prevent teardown madness, stop dropping uniquing just because an operand
drops to null.

Part of PR21532.

llvm-svn: 225223
2015-01-05 23:31:54 +00:00
Duncan P. N. Exon Smith
1c00c9f7fc IR: Prune arguments to ValueAsMetadata::ValueAsMetadata()
`LLVMContext` isn't actually used.

llvm-svn: 225200
2015-01-05 20:41:25 +00:00
Chandler Carruth
539dc4b9d5 [PM] Don't run the machinery of invalidating all the analysis passes
when all are being preserved.

We want to short-circuit this for a couple of reasons. One, I don't
really want passes to grow a dependency on actually receiving their
invalidate call when they've been preserved. I'm thinking about removing
this entirely. But more importantly, preserving everything is likely to
be the common case in a lot of scenarios, and it would be really good to
bypass all of the invalidation and preservation machinery there.
Avoiding calling N opaque functions to try to invalidate things that are
by definition still valid seems important. =]

This wasn't really inpsired by much other than seeing the spam in the
logging for analyses, but it seems better ot get it checked in rather
than forgetting about it.

llvm-svn: 225163
2015-01-05 12:32:11 +00:00
Chandler Carruth
e5e8fb3bf6 [PM] Add names and debug logging for analysis passes to the new pass
manager.

This starts to allow us to test analyses more easily, but it's really
only the beginning. Some of the code here is still untestable without
manual changes to create analysis passes, but I wanted to factor it into
a small of chunks as possible.

Next up in order to be able to test things are, in no particular order:
- No-op analyses passes so we don't have to use real ones to exercise
  the pass maneger itself.
- Automatic way of generating dummy passes that require an analysis be
  run, including a variant that calls a 'print' method on a pass to make
  it even easier to print out the results of an analysis.
- Dummy passes that invalidate all analyses for their IR unit so we can
  test invalidation and re-runs.
- Automatic way to print each analysis pass as it is re-run.
- Automatic but optional verification of analysis passes everywhere
  possible.

I'm not claiming I'll get to all of these immediately, but that's what
is in the pipeline at some stage. I'm fleshing out exactly what I need
and what to prioritize by working on converting analyses and then trying
to test the conversion. =]

llvm-svn: 225162
2015-01-05 12:21:44 +00:00
Chandler Carruth
d174ce4ad1 [PM] Switch the new pass manager to use a reference-based API for IR
units.

This was debated back and forth a bunch, but using references is now
clearly cleaner. Of all the code written using pointers thus far, in
only one place did it really make more sense to have a pointer. In most
cases, this just removes immediate dereferencing from the code. I think
it is much better to get errors on null IR units earlier, potentially
at compile time, than to delay it.

Most notably, the legacy pass manager uses references for its routines
and so as more and more code works with both, the use of pointers was
likely to become really annoying. I noticed this when I ported the
domtree analysis over and wrote the entire thing with references only to
have it fail to compile. =/ It seemed better to switch now than to
delay. We can, of course, revisit this is we learn that references are
really problematic in the API.

llvm-svn: 225145
2015-01-05 02:47:05 +00:00
Chandler Carruth
ce08983110 [PM] Fix some formatting where clang-format has improved recently.
llvm-svn: 225092
2015-01-02 22:51:44 +00:00
Elena Demikhovsky
84d1997b95 Some code improvements in Masked Load/Store.
No functional changes.

llvm-svn: 224986
2014-12-30 14:28:14 +00:00
Philip Reames
4750dd18ea Add IRBuilder routines for gc.statepoints, gc.results, and gc.relocates
Nothing particularly interesting, just adding infrastructure for use by in tree users and out of tree users.

Note: These were extracted out of a working frontend, but they have not been well tested in isolation.

Differential Revision: http://reviews.llvm.org/D6807

llvm-svn: 224981
2014-12-30 05:55:58 +00:00
Elena Demikhovsky
fb81b93e17 Masked Load/Store - Changed the order of parameters in intrinsics.
No functional changes.
The documentation is coming.

llvm-svn: 224829
2014-12-25 07:49:20 +00:00
Adrian Prantl
48af2ef40f DIBuilder: Similar to createPointerType, make createMemberPointerType take
a size and alignment. Several assertions in DwarfDebug rely on all variable
types to report back a size, or to be derived from a type with a size.

Tested in CFE.

llvm-svn: 224780
2014-12-23 19:11:47 +00:00
Rafael Espindola
366e5c1bf1 The leak detector is dead, long live asan and valgrind.
In resent times asan and valgrind have found way more memory management bugs
in llvm than the special purpose leak detector.

llvm-svn: 224703
2014-12-22 13:00:36 +00:00
Yaron Keren
e8270225a2 Remove isSubroutineType test for isCompositeType, getTag() is enough.
llvm-svn: 224621
2014-12-19 22:15:09 +00:00
David Majnemer
824e011ad7 ConstantFold: Shifting undef by zero results in undef
llvm-svn: 224553
2014-12-18 23:54:43 +00:00
Duncan P. N. Exon Smith
97f07c2778 IR: Handle self-referencing DICompositeTypes in DIBuilder
Add API to DIBuilder to handle self-referencing `DICompositeType`s.

Self-references aren't expected in the debug info graph, and we take
advantage of that by only calling `resolveCycles()` on nodes that were
once forward declarations (otherwise, DIBuilder needs an expensive
tracking reference to every unresolved node it creates, which in cyclic
graphs is *all of them*).

However, clang seems to create self-referencing `DICompositeType`s.  Add
API to manage this safely.  The paired commit to clang will include the
regression test.

I'll make the `DICompositeType` API `private` in a follow-up to prevent
misuse (I've separated that to prevent build failures from missing the
clang commit).

llvm-svn: 224482
2014-12-18 00:46:16 +00:00
JF Bastien
e6acbdc487 Random Number Generator Refactoring (removing from Module)
This patch removes the RNG from Module. Passes should instead create a new RNG for their use as needed.

Patch by Stephen Crane @rinon.

Differential revision: http://reviews.llvm.org/D4377

llvm-svn: 224444
2014-12-17 18:12:10 +00:00
Nick Lewycky
52ee5e446b Delete debugging cruft that crept in with r223802.
llvm-svn: 224407
2014-12-17 01:56:51 +00:00
Rafael Espindola
a4a94f1b55 Use CastInst::castIsValid to simplify the verifier.
Also delete a dead member variable.

llvm-svn: 224356
2014-12-16 19:29:29 +00:00
Duncan P. N. Exon Smith
bb7d2fb1e5 IR: Stop printing 'metadata' in Metadata::print()
Stop printing `metadata` in `Metadata::print()` and
`Metadata::printAsOperand()`.

llvm-svn: 224327
2014-12-16 07:40:31 +00:00
Duncan P. N. Exon Smith
fee167fcc0 IR: Make MDNode::dump() useful by adding addresses
It's horrible to inspect `MDNode`s in a debugger.  All of their operands
that are `MDNode`s get dumped as `<badref>`, since we can't assign
metadata slots in the context of a `Metadata::dump()`.  (Why not?  Why
not assign numbers lazily?  Because then each time you called `dump()`,
a given `MDNode` could have a different lazily assigned number.)

Fortunately, the C memory model gives us perfectly good identifiers for
`MDNode`.  Add pointer addresses to the dumps, transforming this:

    (lldb) e N->dump()
    !{i32 662302, i32 26, <badref>, null}

    (lldb) e ((MDNode*)N->getOperand(2))->dump()
    !{i32 4, !"foo"}

into:

    (lldb) e N->dump()
    !{i32 662302, i32 26, <0x100706ee0>, null}

    (lldb) e ((MDNode*)0x100706ee0)->dump()
    !{i32 4, !"foo"}

and this:

    (lldb) e N->dump()
    0x101200248 = !{<badref>, <badref>, <badref>, <badref>, <badref>}

    (lldb) e N->getOperand(0)
    (const llvm::MDOperand) $0 = {
      MD = 0x00000001012004e0
    }
    (lldb) e N->getOperand(1)
    (const llvm::MDOperand) $1 = {
      MD = 0x00000001012004e0
    }
    (lldb) e N->getOperand(2)
    (const llvm::MDOperand) $2 = {
      MD = 0x0000000101200058
    }
    (lldb) e N->getOperand(3)
    (const llvm::MDOperand) $3 = {
      MD = 0x00000001012004e0
    }
    (lldb) e N->getOperand(4)
    (const llvm::MDOperand) $4 = {
      MD = 0x0000000101200058
    }
    (lldb) e ((MDNode*)0x00000001012004e0)->dump()
    !{}

    (lldb) e ((MDNode*)0x0000000101200058)->dump()
    !{null}

into:

    (lldb) e N->dump()
    !{<0x1012004e0>, <0x1012004e0>, <0x101200058>, <0x1012004e0>, <0x101200058>}

    (lldb) e ((MDNode*)0x1012004e0)->dump()
    !{}

    (lldb) e ((MDNode*)0x101200058)->dump()
    !{null}

llvm-svn: 224325
2014-12-16 07:09:37 +00:00
Duncan P. N. Exon Smith
be7ea19b58 IR: Make metadata typeless in assembly
Now that `Metadata` is typeless, reflect that in the assembly.  These
are the matching assembly changes for the metadata/value split in
r223802.

  - Only use the `metadata` type when referencing metadata from a call
    intrinsic -- i.e., only when it's used as a `Value`.

  - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode`
    when referencing it from call intrinsics.

So, assembly like this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata !{i32 %v}, metadata !0)
      call void @llvm.foo(metadata !{i32 7}, metadata !0)
      call void @llvm.foo(metadata !1, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{metadata !3}, metadata !0)
      ret void, !bar !2
    }
    !0 = metadata !{metadata !2}
    !1 = metadata !{i32* @global}
    !2 = metadata !{metadata !3}
    !3 = metadata !{}

turns into this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata i32 %v, metadata !0)
      call void @llvm.foo(metadata i32 7, metadata !0)
      call void @llvm.foo(metadata i32* @global, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{!3}, metadata !0)
      ret void, !bar !2
    }
    !0 = !{!2}
    !1 = !{i32* @global}
    !2 = !{!3}
    !3 = !{}

I wrote an upgrade script that handled almost all of the tests in llvm
and many of the tests in cfe (even handling many `CHECK` lines).  I've
attached it (or will attach it in a moment if you're speedy) to PR21532
to help everyone update their out-of-tree testcases.

This is part of PR21532.

llvm-svn: 224257
2014-12-15 19:07:53 +00:00
Duncan P. N. Exon Smith
121eeff4f3 IR: Don't track nullptr on metadata RAUW
The RAUW support in `Metadata` supports going to `nullptr` specifically
to handle values being deleted, causing `ValueAsMetadata` to be deleted.

Fix the case where the reference is from a `TrackingMDRef` (as opposed
to an `MDOperand` or a `MetadataAsValue`).

This is surprisingly rare -- metadata tracked by `TrackingMDRef` going
to null -- but it came up in an openSUSE bootstrap during inlining.  The
tracking ref was held by the `ValueMap` because it was referencing a
local, the basic block containing the local became dead after it had
been merged in, and when the local was deleted, the tracking ref
asserted in an `isa`.

llvm-svn: 224146
2014-12-12 19:24:33 +00:00
Matthias Braun
0880c6098f Document that PassManager::add() may delete the pass right away.
Also remove redundant documentation:
- doxygen will copy documentation to overriden methods.
- Use \copydoc on PIMPL classes instead of replicating the text.

llvm-svn: 224089
2014-12-12 01:27:01 +00:00
Duncan P. N. Exon Smith
63eb6bf623 IR: Store MDNodes in a separate LeakDetector container
This gives us better leak detection messages, like `Value` has.

This also has the side effect of papering over a problem where
`MachineInstr`s are added as garbage to the leak detector and then
deleted without being removed.  If `MDNode::getTemporary()` allocates an
`MDNodeFwdDecl` in the same spot, the leak detector asserts.  By
separating `MDNode`s into their own container we lose that assertion.

Since `MachineInstr` is required to have a trivial destructor, its usage
of `LeakDetector` at all is pretty suspect.  I'll be sending a patch
soon to strip that out.

llvm-svn: 224060
2014-12-11 21:39:39 +00:00
Nick Lewycky
dde76ff09c Fix LLVMContext to match what MDKind names that the LL parser permits. Fixes PR21799!
llvm-svn: 223995
2014-12-11 02:10:28 +00:00
David Majnemer
3729668056 ConstantFold: Clean up X * undef code
No functional change intended.

llvm-svn: 223970
2014-12-10 21:58:17 +00:00
David Majnemer
5a7717e498 ConstantFold, InstSimplify: undef >>a x can be either -1 or 0, choose 0
Zero is usually a nicer constant to have than -1.

llvm-svn: 223969
2014-12-10 21:58:15 +00:00
David Majnemer
89cf6d79eb ConstantFold: an undef shift amount results in undef
X shifted by undef results in undef because the undef value can
represent values greater than the width of the operands.

llvm-svn: 223968
2014-12-10 21:38:05 +00:00
David Majnemer
7b86b77248 ConstantFold: div undef, 0 should fold to undef, not zero
Dividing by zero yields an undefined value.

llvm-svn: 223924
2014-12-10 09:14:55 +00:00
David Majnemer
612f31284e DataLayout: Provide nicer diagnostics for malformed strings
llvm-svn: 223911
2014-12-10 02:36:41 +00:00
Duncan P. N. Exon Smith
f14b1df55b IR: Move call to dropAllReferences() to MDNode subclasses
Don't call `dropAllReferences()` from `MDNode::~MDNode()`, call it
directly from `~MDNodeFwdDecl()` and `~GenericMDNode()`.

llvm-svn: 223904
2014-12-10 01:45:04 +00:00
David Majnemer
2dc1b0f514 DataLayout: Be more verbose when diagnosing problems in pointer specs
llvm-svn: 223903
2014-12-10 01:38:28 +00:00
David Majnemer
5330c69bd1 DataLayout: Move asserts over to report_fatal_error
As indicated by the tests, it is possible to feed the AsmParser an
invalid datalayout string.  We should verify the result of parsing this
string regardless of whether or not we have assertions enabled.

llvm-svn: 223898
2014-12-10 01:17:08 +00:00
Duncan P. N. Exon Smith
22600ff328 IR: Fix memory corruption in MDNode new/delete
There were two major problems with `MDNode` memory management.

 1. `MDNode::operator new()` called a placement array constructor for
    `MDOperand`.  What?  Each operand needs to be placed individually.

 2. `MDNode::operator delete()` failed to destruct the `MDOperand`s at
    all.

Frankly it's hard to understand how this worked locally, how this
survived an LTO bootstrap, or how it worked on most of the bots.

llvm-svn: 223858
2014-12-09 23:56:39 +00:00
Duncan P. N. Exon Smith
d167eac023 IR: Metadata: Detect an RAUW recursion
Speculatively handle a recursion in
`GenericMDNode::handleChangedOperand()`.  I'm hoping this fixes the
failing hexagon bot [1].

[1]: http://lab.llvm.org:8011/builders/llvm-hexagon-elf/builds/13434

llvm-svn: 223849
2014-12-09 23:04:59 +00:00
Duncan P. N. Exon Smith
21909e35cb IR: Metadata/Value split: RAUW in a deterministic order
RAUW in a deterministic order to try to recover the hexagon bot [1],
whose tests started failing once my GCC fixes were in for r223802.

Otherwise, I'm not sure why tests would fail there and not here.

[1]: http://lab.llvm.org:8011/builders/llvm-hexagon-elf/builds/13426

llvm-svn: 223829
2014-12-09 21:12:56 +00:00
Hans Wennborg
e242e8b064 Try fixing MSVC build after r223802
LLVM_EXPLICIT is only supported by recent version of MSVC, and it seems
the not-so-recent versions get confused about the operator bool() when
tryint to resolve operator== calls.

This removed the operator bool()'s since they don't seem to be used
anyway.

llvm-svn: 223824
2014-12-09 20:39:15 +00:00
Duncan P. N. Exon Smith
562283189d Fix a GCC build failure from r223802
llvm-svn: 223806
2014-12-09 18:52:38 +00:00
Duncan P. N. Exon Smith
5bf8fef580 IR: Split Metadata from Value
Split `Metadata` away from the `Value` class hierarchy, as part of
PR21532.  Assembly and bitcode changes are in the wings, but this is the
bulk of the change for the IR C++ API.

I have a follow-up patch prepared for `clang`.  If this breaks other
sub-projects, I apologize in advance :(.  Help me compile it on Darwin
I'll try to fix it.  FWIW, the errors should be easy to fix, so it may
be simpler to just fix it yourself.

This breaks the build for all metadata-related code that's out-of-tree.
Rest assured the transition is mechanical and the compiler should catch
almost all of the problems.

Here's a quick guide for updating your code:

  - `Metadata` is the root of a class hierarchy with three main classes:
    `MDNode`, `MDString`, and `ValueAsMetadata`.  It is distinct from
    the `Value` class hierarchy.  It is typeless -- i.e., instances do
    *not* have a `Type`.

  - `MDNode`'s operands are all `Metadata *` (instead of `Value *`).

  - `TrackingVH<MDNode>` and `WeakVH` referring to metadata can be
    replaced with `TrackingMDNodeRef` and `TrackingMDRef`, respectively.

    If you're referring solely to resolved `MDNode`s -- post graph
    construction -- just use `MDNode*`.

  - `MDNode` (and the rest of `Metadata`) have only limited support for
    `replaceAllUsesWith()`.

    As long as an `MDNode` is pointing at a forward declaration -- the
    result of `MDNode::getTemporary()` -- it maintains a side map of its
    uses and can RAUW itself.  Once the forward declarations are fully
    resolved RAUW support is dropped on the ground.  This means that
    uniquing collisions on changing operands cause nodes to become
    "distinct".  (This already happened fairly commonly, whenever an
    operand went to null.)

    If you're constructing complex (non self-reference) `MDNode` cycles,
    you need to call `MDNode::resolveCycles()` on each node (or on a
    top-level node that somehow references all of the nodes).  Also,
    don't do that.  Metadata cycles (and the RAUW machinery needed to
    construct them) are expensive.

  - An `MDNode` can only refer to a `Constant` through a bridge called
    `ConstantAsMetadata` (one of the subclasses of `ValueAsMetadata`).

    As a side effect, accessing an operand of an `MDNode` that is known
    to be, e.g., `ConstantInt`, takes three steps: first, cast from
    `Metadata` to `ConstantAsMetadata`; second, extract the `Constant`;
    third, cast down to `ConstantInt`.

    The eventual goal is to introduce `MDInt`/`MDFloat`/etc. and have
    metadata schema owners transition away from using `Constant`s when
    the type isn't important (and they don't care about referring to
    `GlobalValue`s).

    In the meantime, I've added transitional API to the `mdconst`
    namespace that matches semantics with the old code, in order to
    avoid adding the error-prone three-step equivalent to every call
    site.  If your old code was:

        MDNode *N = foo();
        bar(isa             <ConstantInt>(N->getOperand(0)));
        baz(cast            <ConstantInt>(N->getOperand(1)));
        bak(cast_or_null    <ConstantInt>(N->getOperand(2)));
        bat(dyn_cast        <ConstantInt>(N->getOperand(3)));
        bay(dyn_cast_or_null<ConstantInt>(N->getOperand(4)));

    you can trivially match its semantics with:

        MDNode *N = foo();
        bar(mdconst::hasa               <ConstantInt>(N->getOperand(0)));
        baz(mdconst::extract            <ConstantInt>(N->getOperand(1)));
        bak(mdconst::extract_or_null    <ConstantInt>(N->getOperand(2)));
        bat(mdconst::dyn_extract        <ConstantInt>(N->getOperand(3)));
        bay(mdconst::dyn_extract_or_null<ConstantInt>(N->getOperand(4)));

    and when you transition your metadata schema to `MDInt`:

        MDNode *N = foo();
        bar(isa             <MDInt>(N->getOperand(0)));
        baz(cast            <MDInt>(N->getOperand(1)));
        bak(cast_or_null    <MDInt>(N->getOperand(2)));
        bat(dyn_cast        <MDInt>(N->getOperand(3)));
        bay(dyn_cast_or_null<MDInt>(N->getOperand(4)));

  - A `CallInst` -- specifically, intrinsic instructions -- can refer to
    metadata through a bridge called `MetadataAsValue`.  This is a
    subclass of `Value` where `getType()->isMetadataTy()`.

    `MetadataAsValue` is the *only* class that can legally refer to a
    `LocalAsMetadata`, which is a bridged form of non-`Constant` values
    like `Argument` and `Instruction`.  It can also refer to any other
    `Metadata` subclass.

(I'll break all your testcases in a follow-up commit, when I propagate
this change to assembly.)

llvm-svn: 223802
2014-12-09 18:38:53 +00:00
Juergen Ributzka
194350a936 Revert "Move function to obtain branch weights into the BranchInst class. NFC."
This reverts commit r223784 and copies the 'ExtractBranchMetadata' to CodeGenPrepare.

llvm-svn: 223795
2014-12-09 17:32:12 +00:00
Juergen Ributzka
e2aa3aa38a Move function to obtain branch weights into the BranchInst class. NFC.
Make this function available to other parts of LLVM.

llvm-svn: 223784
2014-12-09 16:36:06 +00:00
David Majnemer
770fd82f39 ConstantFold: Zero-sized globals might land on top of another global
A zero sized array is zero sized and might share its address with
another global.

llvm-svn: 223684
2014-12-08 19:35:31 +00:00
Duncan P. N. Exon Smith
9c51b50a71 IR: Revert r223618 behaviour of MDNode::concatenate()
r223618 including special handling of `MDNode::intersect()`: if the
first operand is a self-reference with the same operands you're trying
to return, return it instead.

Reuse that handling in `MDNode::concatenate()` in the hopes that it
fixes a polly test that seems to rely on the old behaviour [1].

[1]: http://lab.llvm.org:8011/builders/polly-amd64-linux/builds/25167

llvm-svn: 223619
2014-12-07 20:32:11 +00:00
Duncan P. N. Exon Smith
ac8ee289eb IR: Drop uniquing for self-referencing MDNodes
It doesn't make sense to unique self-referencing nodes.  Drop uniquing
for them.

Note that `MDNode::intersect()` occasionally returns self-referencing
nodes.  Previously these would be returned by `MDNode::get()`.  I'm not
convinced this was intended behaviour -- to me it seems it should return
a node whose only operand is the self-reference -- but I don't know much
about alias scopes so I'm preserving it for now.

This is part of PR21532.

llvm-svn: 223618
2014-12-07 19:52:06 +00:00
Benjamin Kramer
3280a5d9f5 Turn some DenseMaps that are only used for set operations into DenseSets.
DenseSet has better memory efficiency now.

llvm-svn: 223589
2014-12-06 19:22:54 +00:00