This enables the linker to match concrete relocation types (absolute or relative) with whatever library or C++ support code is being linked against.
llvm-svn: 149057
When not using subsections via symbols, the assembler can resolve
symbol differences (including pcrel references) to non-local
labels at assembly time, not just those in the same atom.
llvm-svn: 148865
If the two fragments are in the same Atom, then the difference
expression is resolvable at compile time. Previously we were checking
that they were in the same fragment, but that breaks down in the
presence of instruction relaxation which has multiple fragments in the
same atom.
rdar://10711829
llvm-svn: 148423
When the non-local symbol in the expression is in the same fragment
as the second symbol, the assembler can still evaluate the expression
without needing a relocation.
For example, on ARM:
_foo:
ldr lr, (_foo - 4)
rdar://10348687
llvm-svn: 148341
directives was in the wrong place and getting triggered incorectly with a
cpp .file directive. This change fixes that and adds a test case.
llvm-svn: 147951
functional change in r147860 to use DW_TAG_label's instead TAG_subprogram's.
This only changes names and updates comments. No functional change.
llvm-svn: 147877
of several newly un-defaulted switches. This also helps optimizers
(including LLVM's) recognize that every case is covered, and we should
assume as much.
llvm-svn: 147861
assembly source when it generates the TAG_subprogram dwarf debug info for
the labels that have nothing between them as in this bit of assembly source:
% cat ZeroLength.s
_func1:
_func2:
nop
One solution would be to not emit the subsequent labels with the same address
and use the next label with a different address or the end of the section for
the AT_high_pc value of the TAG_subprogram.
Turns out in llvm-mc it is not possible in all cases to determine of two
symbols have the same value at the point we put out the TAG_subprogram dwarf
debug info.
So we will have llvm-mc instead of putting out TAG_subprogram's put out
DW_TAG_label's. And the DW_TAG_label does not have a AT_high_pc value which
avoids the problem.
This commit is only the functional change to make the diffs clear as to what is
really being changed. The next commit will be to clean up the names of such
things like MCGenDwarfSubprogramEntry to something like MCGenDwarfLabelEntry.
rdar://10666925
llvm-svn: 147860
file error checking. Use that to error on an unfinished cfi_startproc.
The error is not nice, but is already better than a segmentation fault.
llvm-svn: 147717
Jim Grosbach