ELFv2 needs different plt call stubs to ELFv1, register usage differs
too. When I added these to ld I changed register usage in the ELFv1
stubs as well, simplifying the linker code and (perhaps) future
maintenance. All well and good, but this means gdb needs to cope with
more stub variants. This patch also handles skipping over addis/addi
setting up r2 in ELFv2 global entry code. We want breakpoints to be
set past this point to catch calls via the local entry point.
* ppc64-tdep.c (ppc64_plt_entry_point): Renamed from..
(ppc64_desc_entry_point): ..this. Update comments here and at
call points.
(ppc64_standard_linkage1, ppc64_standard_linkage2,
ppc64_standard_linkage3): Update comments.
(ppc64_standard_linkage4, ppc64_standard_linkage5,
(ppc64_standard_linkage6, ppc64_standard_linkage7): New insn
patterns.
(ppc64_standard_linkage4_target): New function.
(ppc64_skip_trampoline_code): Skip ELFv2 patterns too.
* rs6000-tdep.c (skip_prologue): Skip ELFv2 r2 setup. Correct
nop match. Fix comment wrap.
* rs6000-tdep.c (read_insn): Add frame param, don't assume big-endian.
(ppc_insns_match_pattern): Add frame param. Avoid multiple
target mem reads on optional insns.
* ppc-linux-tdep.c (ppc_skip_trampoline_code): Update
ppc_insns_match_pattern calls.
* ppc64-tdep.c (ppc64_standard_linkage2, ppc64_standard_linkage3):
Add match for power7 thread safety insns, and new order of
std 2,40(1) insn. Correct code shown for _dl_runtime_resolve
invocation in comment, and update rest of comment.
(PPC64_STANDARD_LINKAGE1_LEN, PPC64_STANDARD_LINKAGE2_LEN,
PPC64_STANDARD_LINKAGE3_LEN): Delete.
(ppc64_standard_linkage2_target): Update insn offsets.
(ppc64_skip_trampoline_code): Use a single insn buffer. Match newer
stubs first. Update calls.
symbol size.
* ppc64-tdep.c (ppc64_elf_make_msymbol_special): New function.
* ppc64-tdep.h (ppc64_elf_make_msymbol_special): Declare.
* ppc-linux-tdep.c (ppc_linux_init_abi): Set up to use the above.
* ppcfbsd-tdep.c (ppcfbsd_init_abi): Likewise.
