Currently we do not de-duplicate library files specified by /defaultlib option.
As a result, the same files are added multiple times to the input graph. In
particular, some popular files, such as kernel32.lib or oldnames.lib, are added
more than 10 times during linking of LLD. That makes the linker slower, as it
needs to parse the same file again and again.

This patch solves the issue by de-duplicating. The same file will be added only
once to the input graph. This patch improved the LLD linking time from 10.5
seconds to 7.7 seconds on my 4-core Core i7 Macbook Pro.

llvm-svn: 196504

llvm-svn: 196196

llvm-svn: 196092

/DEBUG option is to make the linker to emit debug information to the resulting
executable. It's not for enable debugging of the linker itself.

llvm-svn: 196040

/MERGE option is a bit complicated for many reasons. Firstly, it takes both
positive and negative arguments. That means we have to have one of three
distinctive values (set, clear or unchange) for each permission bit. In this
patch we represent the three values using two bitmasks.

Secondly, the permissions specified by the parameter is bitwise or-ed with the
default permissions of a section. There is an exception for that rule; if one
of READ, WRITE or EXECUTE bit is specified, unspecified bits need to be
cleared. (So if you specify only WRITE for example, the resulting section will
not have WRITE nor EXECUTE bits.)

Lastly, multiple /merge options are allowed.

llvm-svn: 195882

The current mapping for /section one character options is really bogus.
Map to the correct flags.

llvm-svn: 195774

This is the first step towards DLL creation support. Resource-only DLLs
don't have entry point address.

llvm-svn: 195510

It's allowed to specify library files *before* object files in the command
line. Object files seems to be processed first, and then their undefined
symbols are resolved from the libraries. This patch implements the compatible
behavior.

llvm-svn: 195295

llvm-svn: 195289

llvm-svn: 195284

llvm-svn: 195281

Also slightly reduces PECOFFLinkingContext's memory footprint (~128B).

llvm-svn: 194787

llvm-svn: 194757

llvm-svn: 194556

This reverts commit r194551 because it broke the buildbot.

llvm-svn: 194552

llvm-svn: 194551

llvm-svn: 194545

These fields are for /align option. Section alignment can be set per-section
basis with /section option too. In order to avoid name conflicts, rename the
existing identifiers to become more specific. No functionality change.

llvm-svn: 194160

/section command line option is to set/reset attributes of the Characteristics
field in the section header. You can set non-default values with this option.
You can make .data section executable with this, for example.

This patch implements the parser of the command line option. The code to use
the parsed values will be committed in a separate patch.

llvm-svn: 194133

llvm-svn: 194130

/defaultlib options can be specified implicitly via the .drectve section, and
it's pretty common that multiple object files add the same library, such as
user32.lib, to the input. We shouldn't add the same library multiple times.

llvm-svn: 194129

Errors in .drectve section were silently ignored. This patch fixes the issue.

llvm-svn: 194110

llvm-svn: 193883

llvm-svn: 193797

llvm-svn: 193712

llvm-svn: 193646

intended for debugging and diagnostic output), just inspect the spelling
to check for specific prefixes in drectve section flags.

In addition to being significantly cheaper and not relying on
a debugging interface, this also avoids creating a temporary string and
binding it to StringRef variable. We then went on to access it after the
memory had been deallocated.

This bug too was caught by ASan. I love ASan so much. =]

llvm-svn: 193487

/merge:<from>=<to> option makes the linker to combine "from" section to "to"
section. This patch is to parse the option. The actual feature will be
implemented in a subsequent patch.

llvm-svn: 193454

llvm-svn: 193446

We really need a test for the manifest file output, but because it depends
on external commands (CVTRES.EXE and RC.EXE), it's not very easy to write it.

llvm-svn: 193445

llvm-svn: 193444

The internal byte array of the SmallString filled by createTemporaryFile() is
not guaranteed to be NUL-terminated. We need to call c_str() to handle it
safely.

llvm-svn: 193442

llvm-svn: 193424

llvm-svn: 193387

llvm-svn: 193384

llvm-svn: 193375

Instead of making the linker to create a manifest XML file in the same
directory as the resulting binary, you can embed the XML as a part of
resource into the executable.

In order to do that, the linker first creates a resource script file containing
the XML file, compile it into a binary resource file with RC.EXE, and then
convert it to a COFF file with CVTRES.EXE.

llvm-svn: 193298

llvm-svn: 193207

llvm-svn: 193201

/manifestfile:<path> specifies an alternative manifest file output path.
Default is "<output-path>.manifest" where <output-path> is the executable's
path.

llvm-svn: 193195