For multi-threaded inferiors on S390 GNU/Linux targets, GDB tried to
update the PER info via ptrace() in a newly attached thread before
assuring that the thread is stopped. Depending on the timing, this
could lead to a GDB internal error. The patch defers the PER info
update until just before resuming the thread.
gdb/ChangeLog:
* s390-linux-nat.c (struct arch_lwp_info): New.
(s390_fix_watch_points): Rename to...
(s390_prepare_to_resume): ...this. Skip the PER info update
unless the watch points have changed.
(s390_refresh_per_info, s390_new_thread): New functions.
(s390_insert_watchpoint): Call s390_refresh_per_info instead of
s390_fix_watch_points.
(s390_remove_watchpoint): Likewise.
(_initialize_s390_nat): Reflect renaming of s390_fix_watch_points.
Register s390_prepare_to_resume.
Recognize S/390 targets with the new vector feature and present their
vector registers appropriately: as 32 new 128-bit wide registers
v0-v31, where the first 16 embed the floating point registers f0-f15.
Each of the full registers v0-v15 is modelled as a pseudo register.
gdb/ChangeLog:
* s390-linux-nat.c (have_regset_vxrs): New static variable.
(s390_linux_fetch_inferior_registers): Handle vector registers, if
present.
(s390_linux_store_inferior_registers): Likewise.
(s390_get_hwcap): Remove function. Embed its logic...
(s390_read_description): ...here. Yield a target description with
vector registers if applicable.
* s390-linux-tdep.c: Include "features/s390-vx-linux64.c",
"features/s390-tevx-linux64.c", "features/s390x-vx-linux64.c", and
"features/s390x-tevx-linux64.c".
(struct gdbarch_tdep) <v0_full_regnum>: New field.
(s390_dwarf_regmap): Add vector registers. Remove bogus entries
for "GNU/Linux-specific registers".
(s390_dwarf_reg_r0l): New enum value.
(s390_dwarf_reg_to_regnum): Support vector registers.
(s390_adjust_frame_regnum): Adjust pseudo DWARF register numbers
of GPR lower halves.
(regnum_is_vxr_full): New function.
(s390_register_name): New function.
(s390_pseudo_register_name): Handle v0-v15, which are composed of
f0-f15 and v0l-v15l.
(s390_pseudo_register_type): Likewise.
(s390_pseudo_register_read): Likewise.
(s390_pseudo_register_write): Likewise.
(s390_value_from_register): Account for the fact that values are
placed left-justified in vector registers.
(s390_pseudo_register_reggroup_p): Add pseudo registers v0-v15 to
the vector reggroup and omit them from the general reggroup.
(s390_regmap_vxrs_low, s390_regmap_vxrs_high): New register maps.
(s390_vxrs_low_regset, s390_vxrs_high_regset): New regsets.
(s390_iterate_over_regset_sections): Add iterations for the two
new vector regsets.
(s390_core_read_description): Yield a target description with
vector registers if applicable.
(s390_gdbarch_init): Handle target descriptions with vector
registers. Add "register_name" gdbarch method.
(_initialize_s390_tdep): Call new tdesc initialization functions.
* s390-linux-tdep.h (HWCAP_S390_VX): New macro.
(S390_V0_LOWER_REGNUM, S390_V1_LOWER_REGNUM, S390_V2_LOWER_REGNUM)
(S390_V3_LOWER_REGNUM, S390_V4_LOWER_REGNUM, S390_V5_LOWER_REGNUM)
(S390_V6_LOWER_REGNUM, S390_V7_LOWER_REGNUM, S390_V8_LOWER_REGNUM)
(S390_V9_LOWER_REGNUM, S390_V10_LOWER_REGNUM)
(S390_V11_LOWER_REGNUM, S390_V12_LOWER_REGNUM)
(S390_V13_LOWER_REGNUM, S390_V14_LOWER_REGNUM)
(S390_V15_LOWER_REGNUM, S390_V16_REGNUM, S390_V17_REGNUM)
(S390_V18_REGNUM, S390_V19_REGNUM, S390_V20_REGNUM)
(S390_V21_REGNUM, S390_V22_REGNUM, S390_V23_REGNUM)
(S390_V24_REGNUM, S390_V25_REGNUM, S390_V26_REGNUM)
(S390_V27_REGNUM, S390_V28_REGNUM, S390_V29_REGNUM)
(S390_V30_REGNUM, S390_V31_REGNUM): New macros.
(S390_NUM_REGS): Adjust value.
(s390_vxrs_low_regset, s390_vxrs_high_regset): Declare.
(tdesc_s390_vx_linux64, tdesc_s390_tevx_linux64)
(tdesc_s390x_vx_linux64, tdesc_s390x_tevx_linux64): Likewise.
* NEWS: Announce S/390 vector register support.
Rather than supplying own supply/collect functions, use the generic
functions regcache_supply_regset and regcache_collect_regset instead.
The register maps are rewritten accordingly and become much shorter
(and better readable) than before.
When checking for the presence of the TDB regset, the current code
interprets ENODATA from PTRACE_GETREGSET as an indication that the TDB
regset *could* occur on this system, but the inferior stopped outside
a transaction. However, the Linux kernel actually reports ENODATA
even on systems without the transactional execution facility. Thus
the logic is now changed to check the TE field in the HWCAP as well.
This version also checks the existence of the TDB regset -- just to be
on the safe side when running on TE-enabled hardware with a kernel
that does not offer the TDB regset for some reason.
gdb/
* s390-linux-nat.c (s390_read_description): Consider the TE field
in the HWCAP for determining 'have_regset_tdb'.
gdbserver/
* linux-s390-low.c (HWCAP_S390_TE): New define.
(s390_arch_setup): Consider the TE field in the HWCAP for
determining 'have_regset_tdb'.
As suggested before, rename the S/390-related source files (tdep and nat)
such that "-linux-" occurs in the file name, like with other GNU/Linux
targets. Since no other operating system is currently supported by GDB
on this architecture, this isn't strictly necessary. But the old names
sometimes caused GDB contributors to miss these files when performing a
change that affects all GNU/Linux targets. The latest such incident was
observed here:
https://sourceware.org/ml/gdb-patches/2013-09/msg00619.html
gdb/
2013-10-30 Andreas Arnez <arnez@linux.vnet.ibm.com>
* s390-tdep.h: Rename to...
* s390-linux-tdep.h: ...here.
* s390-tdep.c: Rename to...
* s390-linux-tdep.c: ...here. Adjust #include.
* s390-nat.c: Rename to...
* s390-linux-nat.c: ...here. Adjust #include.
* config/s390/s390.mh: Rename to...
* config/s390/linux.mh: ...here. Reflect rename s390-nat.o ->
s390-linux-nat.o.
* configure.host: Reflect host rename "s390" -> "linux".
* configure.tgt: Reflect rename s390-tdep.o -> s390-linux-tdep.o.
* Makefile.in (ALL_TARGET_OBS): Likewise.
(HFILES_NO_SRCDIR): Reflect rename s390-tdep.h ->
s390-linux-tdep.h.
(ALLDEPFILES): Reflect rename of .c files.
