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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223849 91177308-0d34-0410-b5e6-96231b3b80d8
Rename static functiom "map" to be more descriptive and to avoid
potential confusion with the std::map type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223853 91177308-0d34-0410-b5e6-96231b3b80d8
AsmParser: Verifier that the contents of a hex integer are hex

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223856 91177308-0d34-0410-b5e6-96231b3b80d8
Forgot to add test for r223856

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223857 91177308-0d34-0410-b5e6-96231b3b80d8
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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223858 91177308-0d34-0410-b5e6-96231b3b80d8
Remove the Module pointer from GCStrategy and GCMetadataPrinter

In the current implementation, GCStrategy is a part of the ownership structure for the gc metadata which describes a Module. It also contains a reference to the module in question. As a result, GCStrategy instances are essentially Module specific.

I plan to transition away from this design. Instead, a GCStrategy will be owned by the LLVMContext. It will be a lightweight policy object which contains no information about the Modules or Functions involved, but can be easily reached given a Function.

The first step in this transition is to remove the direct Module reference from GCStrategy. This also requires removing the single user of this reference, the GCMetadataPrinter hierarchy. In theory, this will allow the lifetime of the printers to be scoped to the LLVMContext as well, but in practice, I'm not actually changing that. (Yet?)

An alternate design would have been to move the direct Module reference into the GCMetadataPrinter and change the keying of the owning maps to explicitly key off both GCStrategy and Module. I'm open to doing it that way instead, but didn't see much value in preserving the per Module association for GCMetadataPrinters.

The next change in this sequence will be to start unwinding the intertwined ownership between GCStrategy, GCModuleInfo, and GCFunctionInfo.

Differential Revision: http://reviews.llvm.org/D6566



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223859 91177308-0d34-0410-b5e6-96231b3b80d8