The major changes are:
1) LinkerOptions has been merged into TargetInfo
2) LinkerInvocation has been merged into Driver
3) Drivers no longer convert arguments into an intermediate (core) argument 
   list, but instead create a TargetInfo object and call setter methods on 
   it. This is only how in-process linking would work. That is, you can 
   programmatically set up a TargetInfo object which controls the linking.
4) Lots of tweaks to test suite to work with driver changes
5) Add the DarwinDriver
6) I heavily doxygen commented TargetInfo.h

Things to do after this patch is committed:
a) Consider renaming TargetInfo, given its new roll. 
b) Consider pulling the list of input files out of TargetInfo. This will 
   enable in-process clients to create one TargetInfo the re-use it with 
   different input file lists.
c) Work out a way for Drivers to format the warnings and error done in 
   core linking.

llvm-svn: 178776

llvm-svn: 178695

llvm-svn: 178693

llvm-svn: 178495

llvm-svn: 178467

llvm-svn: 178466

llvm-svn: 178323

llvm-svn: 178269

llvm-svn: 178268

llvm-svn: 178027

[ELF][Hexagon] Fixing failing test on Bots, few symbol names are available only in debug builds, dont check the symbol names

llvm-svn: 177991

[ELF] no change in functionality, add functions to symbol table so that they can be overridden by derived classes

llvm-svn: 177990

llvm-svn: 177970

llvm-svn: 177969

llvm-svn: 177875

llvm-svn: 177604

llvm-svn: 177603

ArrayRef<uint8_t>::equals(); lowers to a byte compare loop :(.

TODO: Figure out if we are getting hash collisions, or just have a lot of equal
content. Also test if crypto hashing the content instead of full compare is
better.

llvm-svn: 177588

llvm-svn: 177564

llvm-svn: 177563

This changes from reading each relocation individually for each section to just
storing the range of relocations. It also counts the relocations to preallocate
the _references array.

llvm-svn: 177562

llvm-svn: 177561

llvm-svn: 177557

Improves performance.

llvm-svn: 177556

This is the standard way of implementing LLVM RTTI.

llvm-svn: 177555

This actually doesn't change behavior with the current LinkerInvocation, but
it's needed when you make reading parallel.

llvm-svn: 177554

llvm-svn: 177484

llvm-svn: 177483

llvm-svn: 177482

llvm-svn: 177424

llvm-svn: 177392

llvm-svn: 177079

llvm-svn: 176970

llvm-svn: 176925

llvm-svn: 176916

This reduces the time spent in this function while linking ASTMatchersTests
from %43 to %2.4 of total link time.

llvm-svn: 176842

[ELF] Set values for bss_start and end symbols properly, If there are two load segments with RW permissions, bss_start and end may get set inappropriate

llvm-svn: 176795

llvm-svn: 176749

llvm-svn: 176748

This only happens when the section header count is > 1024.

llvm-svn: 176747