The export table descriptor is a data structure to keep information
about the export table. It contains a symbol name, and the name may
or may not be mangled.
We need unmangled names for the export table, so we demangle them
before writing them to the export table.
Obviously this is not a correct round-trip conversion. That could
drop a leading underscore from a symbol because that's
indistinguishable from a mangled name.
What we need to do is to keep unmangled names. This patch does that.
llvm-svn: 218345
/machine:ebc was previously recognized but rejected. Unknown architecture
names were handled differently but eventually rejected too. We don't need
to distinguish them.
llvm-svn: 218344
Accept /machine:arm as an argument. This is changed to support ARM NT.
Although there is no way to differentiate between ARM (Windows CE) and ARM NT
(Windows on ARM), since LLVM currently only supports Windows on ARM, simply take
/machine:arm to mean Windows on ARM.
llvm-svn: 218105
If we are creating a PE+ executable, we need to run cvtres with
/machine:x64 instead of /machine:x86. Otherwise the resulting executable
would be invalid.
llvm-svn: 217214
The implementation of AMD64 relocations was imcomplete
and wrong. On AMD64, we of course have to use AMD64
relocations instead of i386 ones. This patch fixes the
issue.
LLD is now able to link hello64.obj (created from
hello64.asm) against user32.lib and kernel32.lib to
create a Win64 binary.
llvm-svn: 216253
/INCLUDE arguments passed as command line options are handled in the
same way as Unix -u. All option values are converted to an undefined
symbol and added to a dummy input file, so that the specified symbols
are resolved.
One tricky thing on Windows is that the option is also allowed to
appear in the object file's directive section. At the time when
it's being read, all (regular) command line options have already
been processed. We cannot add undefined atoms to the dummy file
anymore.
Previously, we added such /INCLUDE to a set that has already been
processed. As a result the options were ignored.
This patch fixes the issue. Now, /INCLUDE symbols in the directive
section are handled as real undefined symbol in the COFF file.
We create an undefined symbol for each /INCLUDE argument and add
it to the file being parsed.
llvm-svn: 214824
The entry point file needs to be processed after all other
object files and before all .lib files. It was processed
after .lib files. That caused an issue that the entry point
function was not resolved from the standard library files.
llvm-svn: 213804
On Windows there are four "main" functions -- main, wmain, WinMain,
or wWinMain. Their parameter types are diffferent. The standard
library provides four different entry functions (i.e.
{w,}{WinMain,main}CRTStartup) for them. You need to use the right
entry routine for your "main" function.
If you give an /entry option, the specified name is used
unconditionally.
Otherwise, the linker needs to select the right one based on
user-supplied entry point function. This can be done after the
linker reads all the input files.
This patch moves the code to determine the entry point function
from the driver to a virtual input file. It also implements the
correct logic for the entry point function selection.
llvm-svn: 213713
This is a part of a larger change to move the entry point
processing to a later pass than the driver. On Windows the default
entry point function varies depending on user-provided functions.
That means the driver is not able to correctly know the entry point
function name. Only passes after the core linker can infer it.
llvm-svn: 213697
Previously we invoked cvtres.exe for each compiled Windows
resource file. The generated files were then concatenated
and embedded to the executable.
That was not the correct way to merge compiled Windows
resource files. If you just concatenate generated files,
only the first file would be recognized and the rest would
be ignored as trailing garbage.
The right way to merge them is to call cvtres.exe with
multiple input files. In this patch we do that in the
Windows driver.
llvm-svn: 212763
Previously the input file for the lib.exe command would be removed
as soon as the command exits, so we couldn't write a test to check
the file contents are correct.
This patch adds /lldmoduledeffile: option to retain a copy of the
temporary file at the given file path, so that you can see the file
if you want.
llvm-svn: 207727
I'm a bit surprised that I have not implemented this yet. This is
definitely needed to handle real-world module definition files.
This patch contains a unit test for r207294.
llvm-svn: 207297
Previously LLD would fail if /OPT:icf, /OPT:lbr or such are specified,
because these command line flags would be handled as unknown ones. We
rather want LLD to ignore these known but yet-to-be-implemented options
for now.
Added tests for the driver as well.
llvm-svn: 206863
LIBRARY directive in a module definition file specifies the output
DLL file name. It also takes an optional value for the base address.
llvm-svn: 206647
Seems getSomething() is more common naming scheme than just a noun
to get something, so renaming these members.
Differential Revision: http://llvm-reviews.chandlerc.com/D3285
llvm-svn: 205589
InputGraph has too many knobs and controls that are not being used. This
patch is to remove dead code, unused features and a class. There are two
things that worth noting, besides simple dead code removal:
1. ControlNode class is removed. We had it as the base class of Group
class, but it provides no functionality particularly meaningful. We now
have shallower class hierarchy that is easier to understand.
2. InputGraph provides a feature to replace a node with its internal data.
It is being used to "expand" some type of node, such as a Linker Script
node, with its actual files. We used to have two options when replacing
it -- ExpandOnly or ExpandAndReplace. ExpandOnly was to expand it but not
remove the node from the tree. There is no use of that option in the code,
so it was a dead feature.
Differential Revision: http://llvm-reviews.chandlerc.com/D3252
llvm-svn: 205363
cast<X> asserts the type is correct and does not return null on failure.
So we should use cast<X> rather than dyn_cast<X> at such places where we
don't expect type conversion could fail.
llvm-svn: 205332
Some Clang build uses .imp not .lib file extension for an import library file,
so we need to treat such file as a library file.
Ideally we should not rely on file extensions to detect file type. Instead
we should use magic bytes at beginning of a file. The GNU-compatible driver
actually does that but it made writing unit tests hard, so I chose an ad-hoc
approach for now.
llvm-svn: 205283
If a response file is given via command line, the final command line
arguments will not appear in the log because the actual arguments are
in the given file.
This patch is to show the final command line if /verbose is specified
to help users.
llvm-svn: 204754
Response file is not NUL terminated, so when creating a StringRef for
the buffer contents, we need to pass the buffer size as well as the
pointer pointing to the buffer.
llvm-svn: 204420
LLD fails to link symbol "_main" if the symbol is in a library file and
the library file is given as a bare argument (i.e. not with /defaultlib
option). It's because library files given as bare arguments are processed
before other libraries given with /defaultlib, so when Linker finds msvcrtd
needs a definition for "_main", the file providing the main function has
already been processed and skipped. Linker don't revisit libraries if it's
not given with /defaultlib.
To fix it this patch change the way of command line handling; files end with
".lib" are treated as if they are given with /defaultlib. I don't believe
it's 100% correct behavior but it's better than before.
llvm-svn: 203892
If the driver finds a command line option in the form of "@filename", the
option will be replaced with the content of the given file. It's an error
if a response file cannot be read.
llvm-svn: 203875
This results in some simplifications to the code where an OwningPtr had to
be used with the previous api and then ownership moved to a unique_ptr for
the rest of lld.
llvm-svn: 203809
Syntactically /SAFESEH is a boolean flag -- you can pass /SAFESEH or /SAFESEH:no.
The meaning of /SAFESEH is as follows.
- If /SAFESEH is specified, the linker will produce an executable with SEH table.
If any input files are not compatible with SEH, it's an error.
- If /SAFESEH:no is specified, the linker will not emit SEH table even if all
input files are compatible with SEH.
- If no option is specified, the linker emits SEH table if all input files are
compatible with SEH.
llvm-svn: 201895
The target machine type affects the meaning of other options, in particular
how to mangle symbols. So we want to handle the option first and then parse
all the other options.
llvm-svn: 200589
Refactor the parser so that the parser can return arbitrary type of parse
result other than a vector of ExportDesc. Parsers for non-EXPORTS directives
will be implemented in different patches. No functionality change.
llvm-svn: 198993
Module-definition (.def) files are the file containing linker directives,
such as export symbols. Because link.exe supports the same features as command
line options, just as some Linker Script commands overlaps with command line
options, use of module-definition file is not really necessary. It provides
an alternative way to specify some linker options.
This patch implements EXPORTS directive. Other directives will be implemented
in the future.
llvm-svn: 198925
I'm not 100% sure but it looks like DLL entry symbol (DLL initializer function
name) should be _DllMainCRTStartup@12. The reason why I'm not very sure is
because I have no idea what "@12" suffix is, but without it the symbol won't
be resolved...
llvm-svn: 198072
The main changes are in:
include/lld/Core/Reference.h
include/lld/ReaderWriter/Reader.h
Everything else is details to support the main change.
1) Registration based Readers
Previously, lld had a tangled interdependency with all the Readers. It would
have been impossible to make a streamlined linker (say for a JIT) which
just supported one file format and one architecture (no yaml, no archives, etc).
The old model also required a LinkingContext to read an object file, which
would have made .o inspection tools awkward.
The new model is that there is a global Registry object. You programmatically
register the Readers you want with the registry object. Whenever you need to
read/parse a file, you ask the registry to do it, and the registry tries each
registered reader.
For ease of use with the existing lld code base, there is one Registry
object inside the LinkingContext object.
2) Changing kind value to be a tuple
Beside Readers, the registry also keeps track of the mapping for Reference
Kind values to and from strings. Along with that, this patch also fixes
an ambiguity with the previous Reference::Kind values. The problem was that
we wanted to reuse existing relocation type values as Reference::Kind values.
But then how can the YAML write know how to convert a value to a string? The
fix is to change the 32-bit Reference::Kind into a tuple with an 8-bit namespace
(e.g. ELF, COFFF, etc), an 8-bit architecture (e.g. x86_64, PowerPC, etc), and
a 16-bit value. This tuple system allows conversion to and from strings with
no ambiguities.
llvm-svn: 197727
/DLLEXPORT is a command line option to export a symbol. __declspec(dllexport)
uses that to make the linker to export DLLExport'ed functions, by adding the
option to .drectve section.
This patch implements the parser of the command line option.
llvm-svn: 197122
/ALTERNATENAME is a rarely-used, undocumented command line option that is
needed to link LLD for release build. It seems that the option is for defining
an weak alias; /alternatename:foo=bar defines weak symbol "foo" for "bar".
If "foo" is defined in an input file, it'll be linked normally and the command
line option will have no effect. If it's not defined, "foo" will be handled
as an alias for "bar".
This patch implements the parser for the option. The actual weak alias handling
will be implemented in a separate patch.
llvm-svn: 196743
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
/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
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
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
/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
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
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