Reapply "blockfreq: Approximate irreducible control flow"

This reverts commit r207287, reapplying r207286.

I'm hoping that declaring an explicit struct and instantiating
`addBlockEdges()` directly works around the GCC crash from r207286.
This is a lot more boilerplate, though.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207438 91177308-0d34-0410-b5e6-96231b3b80d8
blockfreq: Remove extra typename from r207438

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207439 91177308-0d34-0410-b5e6-96231b3b80d8
blockfreq: Remove more extra typenames from r207438

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207440 91177308-0d34-0410-b5e6-96231b3b80d8
DwarfDebug: Omit DW_AT_object_pointer on inlined_subroutines

While refactoring out constructScopeDIE into two functions I realized we
were emitting DW_AT_object_pointer in the inlined subroutine when we
didn't need to (GCC doesn't, and the abstract subprogram definition has
the information already).

So here's the refactoring and the bug fix. This is one step of
refactoring to remove some subtle memory ownership semantics. It turns
out the original constructScopeDIE returned ownership in its return
value in some cases and not in others. The split into two functions now
separates those two semantics - further cleanup (unique_ptr, etc) will
follow.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207441 91177308-0d34-0410-b5e6-96231b3b80d8
Improve explicit memory ownership of DIEs

Now that the subtle constructScopeDIE has been refactored into two
functions - one returning memory to take ownership of, one returning a
pointer to already owning memory - push unique_ptr through more APIs.

I think this completes most of the unique_ptr ownership of DIEs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207442 91177308-0d34-0410-b5e6-96231b3b80d8
Reformat, 80-col, tab characters, etc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207444 91177308-0d34-0410-b5e6-96231b3b80d8
Add an option for evaluating past symbols.

When evaluating an assembly expression for a relocation, we want to
stop at MCSymbols that are in the symbol table, even if they are variables.
This is needed since the semantics may require that the relocation use them.

That is not the case when computing the value of a symbol in the symbol table.
There are no relocations in this case and we have to keep going until we hit
a section or find out that the expression doesn't have an assembly time
value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207445 91177308-0d34-0410-b5e6-96231b3b80d8