(external was really undefined and there wasn't an explicit representation for
absolute symbols).
- This still needs some cleanup to how the absolute "pseudo" section is dealt
with, but I haven't figured out the nicest approach yet.
llvm-svn: 79733
- 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
MCAsmStreamer. Based on this, eliminate the current section from AsmPrinter.
While I'm at it, clean up the last of the horrible "switch to null section" stuff
and add an assert. This change is in preparation for completely eliminating
asmprinter::switchtosection.
llvm-svn: 79324
doing it directly. This requires const'izing a bunch of stuff that
took sections, but this seems like the right semantic thing to do:
emitting a label to a section shouldn't mutate the MCSection object
itself, for example.
llvm-svn: 79227
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
instead of syntactically as a string. This means that it keeps track of the
segment, section, flags, etc directly and asmprints them in the right format.
This also includes parsing and validation support for llvm-mc and
"attribute(section)", so we should now start getting errors about invalid
section attributes from the compiler instead of the assembler on darwin.
Still todo:
1) Uniquing of darwin mcsections
2) Move all the Darwin stuff out to MCSectionMachO.[cpp|h]
3) there are a few FIXMEs, for example what is the syntax to get the
S_GB_ZEROFILL segment type?
llvm-svn: 78547
2. Move section switch printing to MCSection virtual method which takes a
TAI. This eliminates textual formatting stuff from TLOF.
3. Eliminate SwitchToSectionDirective, getSectionFlagsAsString, and
TLOFELF::AtIsCommentChar.
llvm-svn: 78510
should have no state that is specific to particular globals in the
section. In this case, it means the removal of the "isWeak" and
"ExplicitSection" bits. MCSection uses the new form of SectionKind.
To handle isWeak, I introduced a new SectionInfo class, which is
SectionKind + isWeak, and it is used by the part of the code generator
that does classification of a specific global.
The ExplicitSection disappears. It is moved onto MCSection as a new
"IsDirective" bit. Since the Name of a section is either a section
or directive, it makes sense to keep this bit in MCSection. Ultimately
the creator of MCSection should canonicalize (e.g.) .text to whatever
the actual section is.
llvm-svn: 77803
the parsing of the .dump and .load should be done in the assembly parser and
not have any need for an MCStreamer API. Changed the code for now so these
just produce an error saying these specific directives are not yet implemented
since they are likely no longer used and may never need to be implemented.
llvm-svn: 76462
This adds location info for all llvm_unreachable calls (which is a macro now) in
!NDEBUG builds.
In NDEBUG builds location info and the message is off (it only prints
"UREACHABLE executed").
llvm-svn: 75640
Make llvm_unreachable take an optional string, thus moving the cerr<< out of
line.
LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for
NDEBUG builds.
llvm-svn: 75379