Patch by Ron Ofir.

llvm-svn: 189151

There may be relocations that may be pointing to the section
even if the section sizes are 0. We shouldnot ignore them
for that regard.

llvm-svn: 189139

There is no change in functionality, this uses the defined way to access
the relocation section that belongs to a particular section.

llvm-svn: 189138

typeTLV content type is used by Darwin to represent thread local
storage. A new contentType has to be made to represent ELF
thread local storage data. These have been set to

- typeThreadZeroFill (represents TBSS storage)
- typeThreadData     (represents TDATA storage)

llvm-svn: 189137

BSS atoms dont take any file space in the Input file. They are associated
with a contentType(typeZeroFill). Similiar zero fill types also exist which
have the same meaning in terms of occupying file space in the Input.

These atoms have to be handled seperately when writing to the
lld's intermediate file or the lld test infrastructure.

Also adds a test.

llvm-svn: 189136

llvm-svn: 189035

llvm-svn: 189025

llvm-svn: 188981

llvm-svn: 188965

llvm-svn: 188963

llvm-svn: 188961

llvm-svn: 188958

This used to be handled automagically by the option parsing library,
but after LLVM r188314, we should handle it ourselves.

No functionality change, but adds a test.

llvm-svn: 188318

This is a temporary measure because the semantics of the common symbol is
actually more compilcated than the simple mergeable symbol.

llvm-svn: 188235

Patch by Ron Ofir.

llvm-svn: 188187

The import name is not always the same as the symbol name. If the name/type
field in the import header is NOPREFIX or UNDECORATE, we need to strip some
characters from symbol to get its import name.

The Microsoft PE/COFF spec is vague if symbol contains more than two
consecutive characters to be stripped. We used to strip all characters,
but it doesn't seem right as we couldn't link against the system library
because of this name mangling. Looks like we shouldn't strip more than one
character.

llvm-svn: 188154

llvm-svn: 188152

llvm-svn: 188150

llvm-svn: 188090

__ImageBase is a symbol having 4 byte integer equal to the image base address
of the resultant executable. The linker is expected to create the symbol as if
it were read from a file.

In order to emit the symbol contents only when the symbol is actually
referenced, we created a pseudo library file to wrap the linker generated
symbol. The library file member is emitted to the output only when the member
is actually referenced, which is suitable for our purpose.

llvm-svn: 188052

llvm-svn: 188049

llvm-svn: 188046

llvm-svn: 188045

The COMDAT section is a section with a special attribute to tell the linker
whether the symbols in the section are allowed to be merged or not. This patch
add a function to interpret the COMDAT data and set "merge" attribute to the
atoms accordingly.

LLD supports multiple policies to merge atoms; atoms can be merged by name or
by content. COFF supports them, and in addition to that, it supports
choose-the-largest-atom policy, which LLD currently does not support. I simply
mapped it to merge-by-name attribute for now, but we eventually have to support
that policy in the core linker.

llvm-svn: 188025

llvm-svn: 188021

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

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

llvm-svn: 187823

llvm-svn: 187690

llvm-svn: 187688

Thanks to Hans' patch (r187675), OptTable now handles "--", so we don't
need this code in LLD.

llvm-svn: 187683

The aim of this patch is to reduce the dependency from COFFDefinedAtom
to COFF structs defined in llvm/Object/COFF.h. Currently many attributes
of the atom are computed in the atom. That provide a simple interface but
does not work well in some cases.

There are some cases that the same type atom is created from different
parts of a COFF file. One example is the BSS atom, which can be created
from the defined symbol in the .bss section or from the undefined symbol.
Computing attributes from different sources in the atom complicates the
code. We should compute it outside the atom.

In the next patch, I'll move more code from Atoms.h to ReaderCOFF.cpp.

llvm-svn: 187681

Summary:
The .drectve section contains linker command line options, and the linker is
expected to interpret them as if they were given via the command line. In this
patch, the command line parser in the driver is called from the object file
reader to parse the string.

I think this patch is important, because this is the first step towards mutable
TargetInfo. We had a discussion about that on llvm-commits mailing list before.
I haven't removed "const" from the function signature yet. Instead, I just use
cast to remove "const". This is a temporary aid for an experiment. If we don't
see any issue with this mutable TargetInfo appraoch, I'll change the function
signature, and rename the class LinkerContext from TargetInfo.

Reviewers: kledzik

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1246

llvm-svn: 187677

For an invalid input we should not call report_fatal_error(), because
when LLD is used as a library, we don't want to kill the whole app
because of a malformed input.

llvm-svn: 187673

llvm-svn: 187670

llvm-svn: 187665

Patch by Ron Ofir.

llvm-svn: 187664

llvm-svn: 187645

A instance of the class always represents a BSS atom, so we don't need
to look at the symbol or the section to retrieve its attributes.

llvm-svn: 187643

It is not needed after LLVM r187546.

llvm-svn: 187551

llvm-svn: 187548

This patch does not change the behavior of LLD, but changes the output of the
help text. We want to show the help text with Windows style indicator rather
than Unix style indicator.

llvm-svn: 187544