[Hexagon] Updating predicate register transfers and adding tstbit to allow select selection.  Updating ll tests with predicate transfers that previously had nop encodings.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223800 91177308-0d34-0410-b5e6-96231b3b80d8
AsmParser: Don't crash on malformed attribute groups

This fixes PR21785.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223801 91177308-0d34-0410-b5e6-96231b3b80d8
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.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223802 91177308-0d34-0410-b5e6-96231b3b80d8
[AVX512] Added lowering for VBROADCASTSS/SD instructions.
Lowering patterns were written through avx512_broadcast_pat multiclass as pattern generates VBROADCAST and COPY_TO_REGCLASS nodes.
Added lowering tests.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223804 91177308-0d34-0410-b5e6-96231b3b80d8
Adding a new option to CMake to disable C++ atexit on llvm-shlib.

Summary:
This is desirable for WebKit and other clients of the llvm-shlib because C++ exit time destructors have a tendency to crash when invoked from multi-threaded applications.

Ideally this option will be temporary, because the ideal fix is to just not have exit time destructors.

Reviewers: chapuni, ributzka

Reviewed By: ributzka

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6572

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223805 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a GCC build failure from r223802

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223806 91177308-0d34-0410-b5e6-96231b3b80d8
Cleanup PatternMatch. NFC.

Tidy up the code a little by using 'auto' when the type is obvious, doxify the
comments, and clang-format the file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223807 91177308-0d34-0410-b5e6-96231b3b80d8
Reorder the code to avoid inserting at the beginning of a vector.

As per dblaikie suggestion, thanks\!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223808 91177308-0d34-0410-b5e6-96231b3b80d8
Remove unneeded curly braces.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223809 91177308-0d34-0410-b5e6-96231b3b80d8
Fix another GCC build failure from r223802

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223810 91177308-0d34-0410-b5e6-96231b3b80d8