With OutputSection being a virtual interface, each concrete OutputSection
handles only one type of chunk and we don't need a base Chunk class.
So for we have a class that handles input sections and one that handles
the string table, but this extends naturally for other outputs (symbol table,
merging of SHF_MERGE sections, etc.).
llvm-svn: 244972
We were creating the string table in a completely ad hoc way. Now the
string table is an output section and gets its output offset set just like
any other section.
This opens the way for other linker created sections like the symbol table.
llvm-svn: 244969
This is a bit more c++ code, but:
* It is less machine code: lld's text is 44688 bytes smaller.
* It should be a bit more efficient in the non native endian case.
* It should be a bit more efficient on architectures with slow unaligned access.
llvm-svn: 244934
Add PT_PHDR segment depending on its availability in linker script's
PHDRS command, fallback if no linker script is given.
Handle FILEHDR, PHDRS and FLAGS attributes of program header.
Differential Revision: http://reviews.llvm.org/D11589
llvm-svn: 244743
Sections must start at page boundaries in memory, but they
can be aligned to sector boundaries (512-bytes) on disk.
We aligned them to 4096-byte boundaries even on disk, so we
wasted disk space a bit.
llvm-svn: 244691
A global variable "Driver" is to re-entry to the driver to parse a
.drectve section. Because the need is COFF-specific, we don't need
this variable for ELF.
llvm-svn: 244680
MSVC 2015's load configuration object (__load_config_used) contains
references to these symbols. I don't fully understand how it works,
but looks like these symbols are linker-defined ones. So I define them
here in the Driver. With this patch, LLD can self-host with MSVC 2015.
This patch is to link MSVC 2015-produced object files. It does not
implement Control Flow Protection. If I understand correctly, the
linker has to create a bitmap of function entry point addresses for
the CFG runtime. We don't do that yet. Produced executables will not
be protected by CFG.
llvm-svn: 244425
SymbolTable::find(mangle(X)) is equivalent to SymbolTable::findUnderscore(X)
except that the latter is slightly efficient as that doesn't allocate a new
string.
llvm-svn: 244377
This has a few advantages
* Less C++ code (about 300 lines less).
* Less machine code (about 14 KB of text on a linux x86_64 build).
* It is more debugger friendly. Just set a breakpoint on the exit function and
you get the complete lld stack trace of when the error was found.
* It is a more robust API. The errors are handled early and we don't get a
std::error_code hot potato being passed around.
* In most cases the error function in a better position to print diagnostics
(it has more context).
llvm-svn: 244215
Various parameters are passed implicitly using Config global variable
already. Output file path is no different from others, so there was no
special reason to handle that differnetly.
This patch changes the signature of writeResult(SymbolTable *, StringRef)
to writeResult(SymbolTable *).
llvm-svn: 244180
We are using Writer more like a function instead of a class.
This patch makes it a function to simplify the interface.
All details of Writer class is now hidden from other parts of the linker.
llvm-svn: 244169
We were printing an error but exiting with 0.
Not sure how to test this. We could add a no-winlib feature,
but that is probably not worth it.
llvm-svn: 244109
It was not using LLVM_LIT_TOOLS_DIR and at least on my VM never finding lib.exe.
With this all the COFF tests show up as supported and pass.
llvm-svn: 244107
The others we have in sight are
* common symbols.
* entries in SHF_MERGE sections.
They will have a substantially different treatment. It is not clear if it is
worth it putting them all in a single list just to dispatch based on the kind on
the other side.
I hope to implement common symbols soon, and then we will be in a position
to have a concrete discussion. For now this is simpler for the the implemented
features.
llvm-svn: 244042
When we were using a std::sort over all the chunks we needed to put them in a
single storage.
Now that we just iterate over them and use a map to find the output section,
we can avoid allocating the temporary storage.
llvm-svn: 243980
Right now PE image section addresses are RVAs and symbol addresses are
VAs. We should probably fix this by changing section addresses to match
symbol addresses. Fixing this might take a few hours, so temporarily
disable the objdump part of this test.
llvm-svn: 243758
I don't remember why I thought that only functions are subject
of garbage collection, but the comment here said so, which is
not correct. Moreover, the code just below the comment does not
do what the comment says -- it handles non-COMDAT, non-function
sections as GC root. As a result, it just handles non-COMDAT
sections as GC root.
This patch cleans that up by removing SectionChunk::isRoot and
use isCOMDAT instead.
llvm-svn: 243700
We want to convince the NT loader not to map these sections into memory.
A good first step is to move them to the end of the executable.
Differential Revision: http://reviews.llvm.org/D11655
llvm-svn: 243680
We create a module-definition file and give that to lib.exe to
create an import library file. A module-definition has to be
syntactically and semantically correct, of course.
There was a case that we created a module-definition file that
lib.exe would complain for duplicate entries. If a user gives
an unmangled and mangled name for the same symbol, we would end
up having two duplicate lines for the mangled name in a module-
definition file.
This patch fixes that issue by uniquefying entries by mangled
symbol name.
llvm-svn: 243587
Rafael Espindola