Replace the "NoFramePointerElimNonLeaf" target option with a function attribute.

There's no need to specify a flag to omit frame pointer elimination on non-leaf
nodes...(Honestly, I can't parse that option out.) Use the function attribute
stuff instead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187093 91177308-0d34-0410-b5e6-96231b3b80d8
Make these methods const correct.

Thanks to Nick Lewycky for noticing it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187098 91177308-0d34-0410-b5e6-96231b3b80d8
Check that TD isn't NULL before dereferencing it down this path.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187099 91177308-0d34-0410-b5e6-96231b3b80d8
Respect llvm.used in Internalize.

The language reference says that:

"If a symbol appears in the @llvm.used list, then the compiler,
assembler, and linker are required to treat the symbol as if there is
a reference to the symbol that it cannot see"

Since even the linker cannot see the reference, we must assume that
the reference can be using the symbol table. For example, a user can add
__attribute__((used)) to a debug helper function like dump and use it from
a debugger.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187103 91177308-0d34-0410-b5e6-96231b3b80d8
Debug Info: improve the verifier to check field types.

Make sure the context and type fields are MDNodes. We will generate
verification errors if those fields are non-empty strings.
Fix testing cases to make them pass the verifier.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187106 91177308-0d34-0410-b5e6-96231b3b80d8