We need .symtab_shndxr if and only if a symbol references a section with an
index >= 0xff00.
The old code was trying to figure out if the section was needed ahead of time,
making it a fairly dependent on the code actually writing the table. It was
also somewhat conservative and would create the section in cases where it was
not needed.
If I remember correctly, the old structure was there so that the sections were
created in the same order gas creates them. That was valuable when MC's support
for ELF was new and we tested with elf-dump.py.
This patch refactors the symbol table creation to another class and makes it
obvious that .symtab_shndxr is really only created when we are about to output
a reference to a section index >= 0xff00.
While here, also improve the tests to use macros. One file is one section
short of needing .symtab_shndxr, the second one has just the right number.
llvm-svn: 204769
The current state of affairs has auxiliary symbols described as a big
bag of bytes. This is less than satisfying, it detracts from the YAML
file as being human readable.
Instead, allow for symbols to optionally contain their auxiliary data.
This allows us to have a much higher level way of describing things like
weak symbols, function definitions and section definitions.
This depends on D3105.
Differential Revision: http://llvm-reviews.chandlerc.com/D3092
llvm-svn: 204214
Summary: These definitions are useful to other aspects of LLVM, move them out.
Reviewers: rafael, nrieck, ruiu
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D3105
llvm-svn: 204213
Since our error_category is based on the std one, we should have the
same visibility for the constructor. This also allows us to avoid
using the _do_message implementation detail in our own categories.
llvm-svn: 203998
The official specifications state the name to be ARMNT (as per the Microsoft
Portable Executable and Common Object Format Specification v8.3).
llvm-svn: 203530
This compiles with no changes to clang/lld/lldb with MSVC and includes
overloads to various functions which are used by those projects and llvm
which have OwningPtr's as parameters. This should allow out of tree
projects some time to move. There are also no changes to libs/Target,
which should help out of tree targets have time to move, if necessary.
llvm-svn: 203083
In some cases it is possible to have a personality 0 unwinding opcodes in the
extab (such as when .handlerdata is used in the assembly). Simply decode the 3
opcodes for that case.
llvm-svn: 201030
utohexstr provides a temporary string, making it unsafe to use with the Twine
interface which will not copy the string. Switch to using std::string.
llvm-svn: 200457
exp2 is not available on Windows. Fortunately, we are calculating powers of 2
with expontents within the range of [4,12]. Simply use an equivalent bitshift
operation to repair compilation with MSVC which does not provide this standard
function.
llvm-svn: 200454
Enhance the ARM specific parsing support in llvm-readobj to support attributes.
This allows for simpler tests to validate encoding of the build attributes as
specified in the ARM ELF specification.
llvm-svn: 200450
None of the object file formats reported error on iterator increment. In
retrospect, that is not too surprising: no object format stores symbols or
sections in a linked list or other structure that requires chasing pointers.
As a consequence, all error checking can be done on begin() and end().
This reduces the text segment of bin/llvm-readobj in my machine from 521233 to
518526 bytes.
llvm-svn: 200442
That bit is not documented in the PE/COFF spec published by Microsoft, so we
don't know the official name of it. I named this bit
IMAGE_DLL_CHARACTERISTICS_HIGH_ENTROPY_VIRTUAL_ADDRESS because the bit is
reported as "high entropy virtual address" by dumpbin.exe,
llvm-svn: 200121
PE32+ supports 64 bit address space, but the file format remains 32 bit.
So its file format is pretty similar to PE32 (32 bit executable). The
differences compared to PE32 are (1) the lack of "BaseOfData" field and
(2) some of its data members are 64 bit.
In this patch, I added a new member function to get a PE32+ Header object to
COFFObjectFile class and made llvm-readobj to use it.
llvm-svn: 200117
Add support to llvm-readobj to decode the actual opcodes. The ARM EHABI opcodes
are a variable length instruction set that describe the operations required for
properly unwinding stack frames.
The primary motivation for this change is to ease the creation of tests for the
ARM EHABI object emission as well as the unwinding directive handling in the ARM
IAS.
Thanks to Logan Chien for an extra test case!
llvm-svn: 199708
I did write a version returning ErrorOr<OwningPtr<Binary> >, but it is too
cumbersome to use without std::move. I will keep the patch locally and submit
when we switch to c++11.
llvm-svn: 199326
Rename bytecode to opcodes to make it more clear. Change an impossible case to
llvm_unreachable instead. Avoid allocation of a buffer by modifying the
PrintOpcodes iteration.
llvm-svn: 198848
This adds some preliminary support for decoding ARM EHABI unwinding information.
The major functionality that remains from complete support is bytecode
translation.
Each Unwind Index Table is printed out as a separate entity along with its
section index, name, offset, and entries.
Each entry lists the function address, and if possible, the name, of the
function to which it corresponds. The encoding model, personality routine or
index, and byte code is also listed.
llvm-svn: 198734
