We do not need to merge ELF flags from DSO. But `isCompatible` is called
for all input files. So this change move ELF flags merging into the
MipsELFFile class.
llvm-svn: 238304
Right now MIPS instantiates MipsTargetHandler using Mips32ELType and
Mips64ELType. And in the future we can add a couple more types. That
leads to the large object file size because compiler has to create
copies of MipsTargetHandler and all realted classes for each types used
for instantiation.
The patch introduces two factory functions and puts each of them into
the separate cpp file. That allows to reduce size of single object file.
llvm-svn: 234728
In case of MIPS O32 ABI linker should merge registers usage masks stored
in the input .reginfo sections and save result into the output .reginfo
section.
The ABI states that the .reginfo section should be put into the separate
segment. This requirement is not implemented in this patch.
llvm-svn: 234103
These functions are "constructors" of the LinkingContexts. We already
have auxiliary classes and functions for ELFLinkingContext in the header.
They fall in the same category.
llvm-svn: 234082
Only MIPS defined the member function, but this feature is not actually
MIPS-specific. Also, the dependency to the MIPS-only member function
prevented us from merging <Arch>ELF{Object,DSO}Reader classes.
This patch moves the feature from MipsLinkingContext to LinkingContext.
llvm-svn: 234068
What we are doing in ELFTarget.h was dubious. In the file, we define
partial classes of <Arch>LinkingContexts to declare only static member
functions. We have different (complete) class definitions in other files.
They would conflict if they exist in the same compilation unit (because
the ones defined in ELFTarget.h has only static member functions).
I don't think this was valid C++.
http://reviews.llvm.org/D8797
llvm-svn: 234039
registerRelocationNames() function is called to register all known
ELF relocation types to the central registry. Since we have separate
LinkingContext class for each ELF machine type, we need to call the
function for each LinkingContext.
However, the function belonged to TargetHandler instead of LinkingContext.
So we needed to do ctx.getTargetHandler().registerRelocationNames().
This patch removes that redundant getTargetHandler call by moving the
function from TargetHandler to LinkingContext.
Conceptually this patch is small, but in reality it's not that small.
It's because the same code is copied to each architecture.
Most of this patch is just repetition. We need to merge them, but
that cannot be done in this patch.
llvm-svn: 233883
In r233772, I removed an empty class, DefaultTargetHandler, from
the class hierarchy by merging the class with TargetHandler. I then
found that TargetHandler and its base class, TargetHandlerBase,
are also almost the same.
We need to go deeper.
In this patch, I merged TargetHandlerBase with TargetHandler.
The only difference between them is the existence (or absense)
of a pure virtual function registerRelocationName(). I added that
function to the (new) TargetHandler.
One more thing is that TargetHandler was templated for no reason.
I made it non-templated class.
llvm-svn: 233773
If input relocation records have RELA format while output dynamic
relocations have REL format the only way to transfer a dynamic
relocation addendum is to save it into the location modified by
the dynamic relocation.
llvm-svn: 233532
This is initial patch to support MIPS64 object files linking.
The patch just makes some classes more generalized, and rejects
attempts to interlinking O32 and N64 ABI object files.
I try to reuse the current MIPS target related classes as much as
possible because O32 and N64 MIPS ABI are tightly related and share
almost the same set of relocations, GOT, flags etc.
llvm-svn: 227058
lldELF is used by each ELF backend. lldELF's ELFLinkingContext
also held a reference to each backend, creating a link-time
cycle. This patch moves the backend references to lldDriver.
Differential Revision: http://reviews.llvm.org/D7119
llvm-svn: 226976
ELFLinkingContext had these two functions, which is really not needed since
the Writer uses a llvm::object template composed of Endianness, Alignment,
Is32bit/64bit. We could just use that and not duplicate functionality.
No Change In Functionality.
llvm-svn: 221523
When committed in r219353, this patch originally caused problems because it was
not tested in debug build. In such scenarios, Driver.cpp adds two additional
passes. These passes serialize all atoms via YAML and reads it back. Since the
patch changed ObjectAtom to hold a new reference, the serialization was removing
the extra data.
This commit implements r219853 in another way, similar to the original MIPS way,
by using a StringSet that holds the names of all copied atoms instead of
directly holding a reference to the copied atom. In this way, this commit is
simpler and eliminate the necessity of changing the DefinedAtom hierarchy to
hold a new data.
Reviewers: shankarke
http://reviews.llvm.org/D5713
llvm-svn: 219449
Enhances the creation of an ELF dynamic executable by avoiding recording
unnecessary shared libraries as NEEDED to load a program.
To do this, we must keep track of not only symbols that were referenced but
also of COPY relocations, which steal the symbol from a shared library but does
not store from which lib this symbol came from. To fix this, this commit changes
ObjectSymbol to store the original library from which this symbol came. With
this information, we are able to build a list of the exact shared libraries that
must be marked as DT_NEEDED, instead of blindly marking all shared libraries as
needed.
This logic originally came from the MIPS backend with some adaptation.
Reviewers: atanasyan, shankar.easwaran
http://reviews.llvm.org/D5574
llvm-svn: 219353
Arrange .ctors/.dtors sections in the following order:
.ctors from crtbegin.o or crtbegin?.o
.ctors from regular object files
.ctors.* (sorted) from regular object files
.ctors from crtend.o or crtend?.o
This order is specific for MIPS traget. For example, on X86
the .ctors.* sections are merged into the .init_array section.
llvm-svn: 209987
1. Re-implement PLT entries and dynamic relocations emitting to keep PLT
and relocations table in a consistent state.
2. Initialize st_value and st_other fields for dynamic symbols table
entry if this entry corresponds to an external function which address is
taken in a non-PIC executable. In that case the st_value field holds an
address of the function's PLT entry. Also set STO_MIPS_PLT bit in the
st_other field.
llvm-svn: 207494
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
The following are the most significant peculiarities of MIPS target:
- MIPS ABI requires some special tags in the dynamic table.
- GOT consists of two parts local and global. The local part contains
entries refer locally visible symbols. The global part contains entries
refer global symbols.
- Entries in the .dynsym section which have corresponded entries in the
GOT should be:
* Emitted at the end of .dynsym section
* Sorted accordingly to theirs GOT counterparts
- There are "paired" relocations. One or more R_MIPS_HI16 and R_MIPS_GOT16
relocations should be followed by R_MIPS_LO16 relocation. To calculate
result of R_MIPS_HI16 and R_MIPS_GOT16 relocations we need to combine
addends from these relocations and paired R_MIPS_LO16 relocation.
The patch reviewed by Michael Spencer, Shankar Easwaran, Rui Ueyama.
http://llvm-reviews.chandlerc.com/D2156
llvm-svn: 197342
Simon Atanasyan