Changes :-

a) Functionality in InputGraph to insert Input elements at any position
b) Functionality in the Resolver to use nextFile
c) Move the functionality of assigning file ordinals to InputGraph
d) Changes all inputs to MemoryBuffers
e) Remove LinkerInput, InputFiles, ReaderArchive

llvm-svn: 192081

In COFF, an undefined symbol can have up to one alternative name. If a symbol
is resolved by its regular name, then it's linked normally. If a symbol is not
found in any input files, all references to the regular name are resolved using
the alternative name. If the alternative name is not found, it's a link error.
This mechanism is called "weak externals".

To support this mechanism, I added a new member function fallback() to undefined
atom. If an undefined atom has the second name, fallback() returns a new undefined
atom that should be used instead of the original one to resolve undefines. If it
does not have the second name, the function returns nullptr.

Differential Revision: http://llvm-reviews.chandlerc.com/D1550

llvm-svn: 190625

Also change some local variable names: "ti" -> "context" and
"_targetInfo" -> "_context".

Differential Revision: http://llvm-reviews.chandlerc.com/D1301

llvm-svn: 187823

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

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: 177079

llvm-svn: 174107

No functionality change.

llvm-svn: 173192

constants and string literals which the linker should coalesce.

llvm-svn: 172495

llvm-svn: 171531

llvm-svn: 171528

now Reader and Writer subclasses for each file format.  Each Reader and
Writer subclass defines an "options" class which controls how that Reader
or Writer operates.

llvm-svn: 157774

Add SharedLibraryFile and ArchiveLibraryFile subclasses of File.

Add command line options to lld-core to set various ResolverOptions settings
and added lots of test cases to verify the options work.

llvm-svn: 155183

class.  Change Resolver to no longer use Platform.  Core linking
now issues errors directly.  We need to factor that out later.

Rework how Darwin executable writer finds "main" atom.  It now
adds to core linking an Atom  which has a Reference to "main".  

llvm-svn: 155060

llvm-svn: 153964

types into the lld namespace.

llvm-svn: 153963

llvm-svn: 153912

llvm-svn: 153677

Also fix some Platform.h includes that somehow got missed last time.

llvm-svn: 153590

shared library) and AbsoluteAtoms (proxy atoms for absolute address (e.g. ROM)).
Redesign weak importing as can-be-null-at-runtime and can-be-null-at-build-time.
Add lots of test cases for all the above.

llvm-svn: 151204

llvm-svn: 150547

llvm-svn: 150539

A couple of big refactorings: 1) Move most attributes of Atom down to DefinedAtom, so only atoms representing definitions need to implement them. 2) Remove definitionTentative, definitionWeak, mergeDuplicates, and autoHide.  Replace with merge and interposable attributes. 3) Make all methods on Atom be virtual so that future object file readers can lazily generated attributes

llvm-svn: 147903

llvm-svn: 147799

llvm-svn: 147571

llvm-svn: 147130

llvm-svn: 146958

llvm-svn: 146844