ours compatible with GAS.
In retrospect, I should have emailed binutils about this earlier. Thanks to
Kai Tietz for pointing out that GAS already had SEH directives.
llvm-svn: 131652
- StartChained and EndChained delimit a chained unwind area, which can contain
additional operations to be undone if an exception occurs inside of it.
- UnwindOnly declares that this function doesn't handle any exceptions. If it
has a handler, it's an unwind handler instead of an exception handler.
- Lsda declares the location and size of the LSDA, which in the Win64 EH
scheme is kept inside the UNWIND_INFO struct. Windows itself ignores the
LSDA; it's used by the Language-Specific Handler (the "Personality Function"
from DWARF).
llvm-svn: 131572
GAS has no such directives (not even mingw-w64 GAS has them), so I took
creative license with their names in assembly. I prefixed them all with
"w64_" to avoid namespace collisions, for example. If I discover that GAS
has taken a different approach, I'll change ours to match.
llvm-svn: 131525
the purposes of the Win64 EH tables, I realized we had no way to tell where
the function ends. (MASM bounds functions with PROC and ENDP keywords.)
Add a directive to delimit the end of the function, and rename the 'frame'
directive to more accurately reflect its duality with the new directive.
llvm-svn: 131522
("T is 1 if the target symbol S has type STT_FUNC and the
symbol addresses a Thumb instruction ;it is 0 otherwise."
from "ELF for the ARM Architecture" 4.7.1.2)
Patch by Koan-Sin Tan!
llvm-svn: 131406
LLVM and binutils.
With this patch, there are no functional differences between the .o
produced directly from LLVM versus the .s to .o via GNU as, for relocation tags
at least, for both PIC and non-PIC modes.
Because some non-PIC reloc tags are used (legally) on PIC, so IsPCRel flag is
necessary but not sufficient to determine whether the overall codegen mode is
PIC or not. Why is this necessary? There is an incompatibility of how relocs
are emitted in the .rodata section. Binutils PIC likes to emit certain relocs
as section relative offsets. Non-PIC does not do this.
So I added a hidden switch on the ELFObjectwriter "-arm-elf-force-pic" which
forces the objectwriter to pretend that all relocs are for PIC mode.
Todo: Activate ForceARMElfPIC to true if -relocation-model=pic is selected
on llc.
Todo: There are probably more issues for PIC mode on ARM/MC/ELF...
Todo: Existing tests in MC/ARM/elf-reloc*.ll need to be converted over to .s
tests as well as expanded to cover the gamut.
llvm-svn: 131205
it is both inefficient and unexpected by dwarfdump. Change to
a DW_FORM_data4.
While in here, change the predicate name to reflect that the position
is not really absolute (it is an offset), just that the linker needs a
relocation.
llvm-svn: 130846
for all symbol differences and can drop the old EmitPCRelSymbolValue
method.
This also make getExprForFDESymbol on ELF equal to the one on MachO, and it
can be made non-virtual.
llvm-svn: 130634
Currently the output should be almost identical to the one produced by CodeGen
to make the transition easier.
The only two differences I know of are:
* Some files get an extra advance loc of size 0. This will be fixed when
relaxations are enabled.
* The optimization of declaring an EH symbol as an external variable is not
implemented. This is a subset of adding the nounwind attribute, so we if really
this at -O0 we should probably do it at the IL level.
llvm-svn: 130623
Charles Davis