These files need AT_PHDR, which is defined in elf.h. If HAVE_GETAUXVAL
is set, it's implicitely included by sys/auxv.h. Include it manually
for the opposite case.
gdb/gdbserver/ChangeLog:
* linux-aarch64-ipa.c: Add <elf.h> include.
* linux-ppc-ipa.c: Add <elf.h> include.
* linux-s390-ipa.c: Add <elf.h> include.
Targets may have various requirements on the required location of the jump
pad area. Currently IPA allocates it at the lowest possible address,
so that it is reachable by branches from the executable. However, this
fails on powerpc, which has executable link address (0x10000000) much
larger than branch reach (+/- 32MiB).
This makes jump pad buffer allocation a target hook instead. The current
implementations are as follows:
- i386 and s390: Branches can reach anywhere, so just mmap it. This
avoids the linear search dance.
- x86_64: Branches have +/-2GiB of reach, and executable is loaded low,
so just call mmap with MAP_32BIT. Likewise avoids the linear search.
- aarch64: Branches have +-128MiB of reach, executable loaded at 4MiB.
Do a linear search from 4MiB-size downwards to page_size.
- s390x: Branches have +-4GiB of reach, executable loaded at 2GiB.
Do like on aarch64.
gdb/gdbserver/ChangeLog:
* linux-aarch64-ipa.c: Add <sys/mman.h> and <sys/auxv.h> includes.
(alloc_jump_pad_buffer): New function.
* linux-amd64-ipa.c: Add <sys/mman.h> include.
(alloc_jump_pad_buffer): New function.
* linux-i386-ipa.c (alloc_jump_pad_buffer): New function.
* linux-s390-ipa.c: Add <sys/mman.h> and <sys/auxv.h> includes.
(alloc_jump_pad_buffer): New function.
* tracepoint.c (getauxval) [!HAVE_GETAUXVAL]: New function.
(initialize_tracepoint): Delegate to alloc_jump_pad_buffer.
* tracepoint.h (alloc_jump_pad_buffer): New prototype.
(getauxval) [!HAVE_GETAUXVAL]: New prototype.
On powerpc64, qSymbol for a function returns the function code address,
and not the descriptor address. Since we emit code calling gdb_collect
and some other functions, we need the descriptor (no way to know the
proper TOC address without it). To get the descriptor address, make
global function pointer variables in the IPA pointing to the relevant
functions and read them instead of asking for them directly via qSymbol.
gdb/gdbserver/ChangeLog:
* linux-aarch64-ipa.c: Rename gdb_agent_get_raw_reg to get_raw_reg.
* linux-amd64-ipa.c: Likewise.
* linux-i386-ipa.c: Likewise.
* linux-s390-ipa.c: Likewise.
* tracepoint.c: IPA-export gdb_collect_ptr instead of gdb_collect,
ditto for get_raw_reg_ptr, get_trace_state_variable_value_ptr,
set_trace_state_variable_value_ptr.
(struct ipa_sym_addresses): Likewise.
(symbol_list): Likewise.
(install_fast_tracepoint): Dereference gdb_collect_ptr instead of
accessing gdb_collect directly.
(gdb_collect_ptr_type): New typedef.
(get_raw_reg_ptr_type): New typedef.
(get_trace_state_variable_value_ptr_type): New typedef.
(set_trace_state_variable_value_ptr_type): New typedef.
(gdb_collect_ptr): New global.
(get_raw_reg_ptr): New global.
(get_trace_state_variable_value_ptr): New global.
(set_trace_state_variable_value_ptr): New global.
(get_raw_reg_func_addr): Dereference get_raw_reg_ptr instead of
accessing get_raw_reg directly.
(get_get_tsv_func_addr): Likewise for
get_trace_state_variable_value_ptr.
(get_set_tsv_func_addr): Likewise for
set_trace_state_variable_value_ptr.
* tracepoint.h: Rename gdb_agent_get_raw_reg to get_raw_reg.
Fast tracepoints will only work on 6-byte intructions, and assume at least
a z900 CPU. s390 also has 4-byte jump instructions, which also work on
pre-z900, but their range is limitted to +-64kiB, which is not very useful
(and wouldn't work at all with current jump pad allocation).
There's a little problem with s390_relocate_instruction function: it
converts BRAS/BRASL instructions to LARL of the return address + JG
to the target address. On 31-bit, this sets the high bit of the target
register to 0, while BRAS/BRASL would set it to 1. While this is not
a problem when the result is only used to address memory, it could
possibly break something that expects to compare such addresses for
equality without first masking the bit off. In particular, I'm not sure
whether leaving the return address high bit unset is ABI-compliant
(could confuse some unwinder?). If that's a problem, it could be fixed
by handling it in the jump pad (since at that point we can just modify
the GPRs in the save area without having to worry about preserving
CCs and only having that one GPR to work with - I'm not sure if it's
even possible to set the high bit with such constraints).
gdb/gdbserver/ChangeLog:
PR 18377
* Makefile.in: Add s390 IPA files.
* configure.srv: Build IPA for s390.
* linux-s390-ipa.c: New file.
* linux-s390-low.c: New includes - inttypes.h and linux-s390-tdesc.h.
(init_registers_s390_linux32): Move declaration to linux-s390-tdesc.h.
(tdesc_s390_linux32): Likewise.
(init_registers_s390_linux32v1): Likewise.
(tdesc_s390_linux32v1): Likewise.
(init_registers_s390_linux32v2): Likewise.
(tdesc_s390_linux32v2): Likewise.
(init_registers_s390_linux64): Likewise.
(tdesc_s390_linux64): Likewise.
(init_registers_s390_linux64v1): Likewise.
(tdesc_s390_linux64v1): Likewise.
(init_registers_s390_linux64v2): Likewise.
(tdesc_s390_linux64v2): Likewise.
(init_registers_s390_te_linux64): Likewise.
(tdesc_s390_te_linux64): Likewise.
(init_registers_s390_vx_linux64): Likewise.
(tdesc_s390_vx_linux64): Likewise.
(init_registers_s390_tevx_linux64): Likewise.
(tdesc_s390_tevx_linux64): Likewise.
(init_registers_s390x_linux64): Likewise.
(tdesc_s390x_linux64): Likewise.
(init_registers_s390x_linux64v1): Likewise.
(tdesc_s390x_linux64v1): Likewise.
(init_registers_s390x_linux64v2): Likewise.
(tdesc_s390x_linux64v2): Likewise.
(init_registers_s390x_te_linux64): Likewise.
(tdesc_s390x_te_linux64): Likewise.
(init_registers_s390x_vx_linux64): Likewise.
(tdesc_s390x_vx_linux64): Likewise.
(init_registers_s390x_tevx_linux64): Likewise.
(tdesc_s390x_tevx_linux64): Likewise.
(have_hwcap_s390_vx): New static variable.
(s390_arch_setup): Fill have_hwcap_s390_vx.
(s390_get_thread_area): New function.
(s390_ft_entry_gpr_esa): New const.
(s390_ft_entry_gpr_zarch): New const.
(s390_ft_entry_misc): New const.
(s390_ft_entry_fr): New const.
(s390_ft_entry_vr): New const.
(s390_ft_main_31): New const.
(s390_ft_main_64): New const.
(s390_ft_exit_fr): New const.
(s390_ft_exit_vr): New const.
(s390_ft_exit_misc): New const.
(s390_ft_exit_gpr_esa): New const.
(s390_ft_exit_gpr_zarch): New const.
(append_insns): New function.
(s390_relocate_instruction): New function.
(s390_install_fast_tracepoint_jump_pad): New function.
(s390_get_min_fast_tracepoint_insn_len): New function.
(s390_get_ipa_tdesc_idx): New function.
(struct linux_target_ops): Wire in the above functions.
(initialize_low_arch) [!__s390x__]: Don't initialize s390x tdescs.
* linux-s390-tdesc.h: New file.
Marcin Kościelnicki