With the compiler changed to use EmitCodeAlignment() it does change the
functionality. But X86 assembly code assembled with llvm-mc does not change
its output. For that we will eventually change the assembler frontend to
detect a '.align x, 0x90' when used in a section that 'hasInstructions' and use
EmitCodeAlignment, but will wait until we have better target hooks.
llvm-svn: 96988
to be aligned with optimal nops. This patch does not change any functionality
and when the compiler is changed to use EmitCodeAlignment() it should also not
change the resulting output. Once the compiler change is made and everything
looks good the next patch with the table of optimal X86 nops will be added to
WriteNopData() changing the output. There are many FIXMEs in this patch which
will be removed when we have better target hooks (coming soon I hear).
llvm-svn: 96963
- I'm still trying to figure out the cleanest way to implement this and match the assembler, currently there are some substantial differences.
llvm-svn: 80347
- I moved section creation back into AsmParser. I think policy decisions like
this should be pushed higher, not lower, when possible (in addition the
assembler has flags which change this behavior, for example).
llvm-svn: 80162
- I haven't really tried to find the "right" way to store the fixups or apply
them, yet. This works, but isn't particularly elegant or fast.
- Still no evaluation support, so we don't actually ever not turn a fixup into
a relocation entry.
llvm-svn: 80089
- The indirect table itself isn't being filled in yet.
- This isn't factored properly and is rather FIXMEd, but at the moment I'm more
focused on figuring out what it needs to do.
llvm-svn: 79910
- This is mostly complete, the main thing missing is .indirect_symbol support
(which would be straight-forward, except that the way it is implemented in
'as' makes getting an exact .o match interesting).
llvm-svn: 79899
- Honor .globl.
- Set symbol type and section correctly ('nm' now works), and order symbols
appropriately.
- Take care to the string table so that the .o matches 'as' exactly (for ease
of testing).
llvm-svn: 79740
- The only .s syntax this honors right now is emitting labels, and some parts
of the symbol table generation are wrong or faked.
- This is enough to get nm to report such symbols... incorrectly, but still.
Also, fixed byte emission to extend the previous fragment if possible.
llvm-svn: 79739
- Together these form the (Mach-O) back end of the assembler.
- MCAssembler is the actual assembler backend, which is designed to have a
reasonable API. This will eventually grow to support multiple object file
implementations, but for now its Mach-O/i386 only.
- MCMachOStreamer adapts the MCStreamer "actions" API to the MCAssembler API,
e.g. converting the various directives into fragments, managing state like
the current section, and so on.
- llvm-mc will use the new backend via '-filetype=obj', which may eventually
be, but is not yet, since I hear that people like assemblers which actually
assemble.
- The only thing that works at the moment is changing sections. For the time
being I have a Python Mach-O dumping tool in test/scripts so this stuff can
be easily tested, eventually I expect to replace this with a real LLVM tool.
- More doxyments to come.
I assume that since this stuff doesn't touch any of the things which are part of
2.6 that it is ok to put this in not so long before the freeze, but if someone
objects let me know, I can pull it.
llvm-svn: 79612