- 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
- 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
(e.g., .objc_message_refs).
- Just emit a .align when we see the directive; this isn't exactly what 'as'
does but in practice it should be ok, at least for now. See FIXME.
llvm-svn: 79697
- 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
symbol as the symbol name itself, not the expression it was defined to. These
have different semantics due to the quirky .set behavior (which absolutizes an
expression that would otherwise be treated as a relocation).
llvm-svn: 79025
specific printer (this only works on x86, for now).
- This makes it possible to do some correctness checking of the parsing and
matching, since we can compare the results of 'as' on the original input, to
those of 'as' on the output from llvm-mc.
- In theory, we could now have an easy ATT -> Intel syntax converter. :)
llvm-svn: 78986
- This doesn't actually improve the algorithm (its still linear), but the
generated (match) code is now fairly compact and table driven. Still need a
generic string matcher.
- The table still needs to be compressed, this is quite simple to do and should
shrink it to under 16k.
- This also simplifies and restructures the code to make the match classes more
explicit, in anticipation of resolving ambiguities.
llvm-svn: 78461
I can clean this up a bit more and do way with the TheCondState and just use
the top element on the TheCondStack if not empty. Also may tweak the code
around ParseConditionalAssemblyDirectives() to simplify the AsmParser code.
llvm-svn: 78423
- Still not very sane, but a least its not 60k lines on X86. :)
- In terms of correctness, currently some things are hard wired for X86, and we
still don't properly resolve ambiguities (this is ignoring the instructions
we don't even match due to funny .td stuff or other corner cases).
The high level changes:
1. Represent tokens which are significant for matching explicitly as separate
operands. This uniformly handles not only the instruction mnemonic, but
also 'signficiant' syntax like the '*' in "call * ...".
2. Separate the matching of operands to an instruction from the construction of
the MCInst. In theory this can be done during matching, but since the number
of variations is small I think it makes sense to decompose the problems.
3. Improved a few of the mechanisms to at least successfully flatten / tokenize
the assembly strings for PowerPC and ARM.
4. The comment at the top of AsmMatcherEmitter.cpp explains the approach I'm
moving towards for handling ambiguous instructions. The high-bit is to infer
a partial ordering of the operand classes (and force the user to specify one
if we can't) and use that to resolve ambiguities.
llvm-svn: 78378
