actuall addresses in a .o file, so it is better to let the MachO writer compute
it.
This is good for two reasons. First, areas that shouldn't care about
addresses now don't have access to it. Second, the layout of each section
is independent. I should use this in a subsequent commit to speed it up.
Most of the patch is just removing the section address computation. The two
interesting parts are the change on how we handle padding in the end
of sections and how MachO can get the address of a-b when a and b are in
different sections.
Since now the expression evaluation normally doesn't know the section address,
it will think that a-b needs relocation and let the MachO writer know. Once
it has computed the section addresses, it calls back the expression evaluation
with the section addresses to resolve these expressions.
The remaining problem is the handling of padding. Currently it will create
a special alignment fragment at the end. Since that fragment doesn't update
the alignment of the section, it needs the real address to be computed.
Since now the layout will not compute a-b with a and b in different sections,
the only effect that the special alignment fragment has is update the
address size of the section. This can also be done by the MachO writer.
llvm-svn: 121076
foo = a - b
.long foo
instead of just
.long a - b
First, on darwin9 64 bits the assembler produces the wrong result. Second,
if "a" is the end of the section all darwin assemblers (9, 10 and mc) will not
consider a - b to be a constant but will if the dummy foo is created.
Split how we handle these cases. The first one is something MC should take care
of. The second one has to be handled by the caller.
llvm-svn: 120889
doing that if the target is darwin10 or newer.
This fixes
*) Direct object emission was producing objects without the workaround on
darwin9.
*) Assembly printing was producing objects with the workaround on linux.
llvm-svn: 120866
darwin9 linker, what is needed to avoid it and where to get more information.
Also make the workaround simpler. Just the regular end_sequence we normally
create is more than 4 bytes.
Tested by building cctools and ld64 from darwin9 on a darwin10 system and using
those. I checked that I was able to reproduce the bootstrap failure when
the the workaround was disabled.
llvm-svn: 120854
contain only data. Handle them specially instead of using AddSectionToTheEnd.
This moves a hack from the generic assembler to the elf writer. It is also
a bit faster and should make other improvements easier.
llvm-svn: 120683
Lifted adjustFixupValue() from Darwin for sharing w ELF.
Test added
TODO:
refactor ELFObjectWriter::RecordRelocation more.
Possibly share more code with Darwin?
Lots more relocations...
llvm-svn: 120534
