diff options
Diffstat (limited to 'gdb/ppc-linux-tdep.c')
| -rw-r--r-- | gdb/ppc-linux-tdep.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c index 3050a9e..441f317 100644 --- a/gdb/ppc-linux-tdep.c +++ b/gdb/ppc-linux-tdep.c @@ -49,6 +49,7 @@ #include "arch-utils.h" #include "xml-syscall.h" #include "linux-tdep.h" +#include "svr4-tls-tdep.h" #include "linux-record.h" #include "record-full.h" #include "infrun.h" @@ -2071,6 +2072,63 @@ ppc64_linux_gcc_target_options (struct gdbarch *gdbarch) return ""; } +/* Fetch and return the TLS DTV (dynamic thread vector) address for PTID. + Throw a suitable TLS error if something goes wrong. */ + +static CORE_ADDR +ppc64_linux_get_tls_dtv_addr (struct gdbarch *gdbarch, ptid_t ptid, + enum svr4_tls_libc libc) +{ + /* On ppc64, the thread pointer is found in r13. Fetch this + register. */ + regcache *regcache + = get_thread_arch_regcache (current_inferior (), ptid, gdbarch); + int thread_pointer_regnum = PPC_R0_REGNUM + 13; + target_fetch_registers (regcache, thread_pointer_regnum); + ULONGEST thr_ptr; + if (regcache->cooked_read (thread_pointer_regnum, &thr_ptr) != REG_VALID) + throw_error (TLS_GENERIC_ERROR, _("Unable to fetch thread pointer")); + + /* The thread pointer (r13) is an address that is 0x7000 ahead of + the *end* of the TCB (thread control block). The field + holding the DTV address is at the very end of the TCB. + Therefore, the DTV pointer address can be found by + subtracting (0x7000+8) from the thread pointer. Compute the + address of the DTV pointer, fetch it, and convert it to an + address. */ + CORE_ADDR dtv_ptr_addr = thr_ptr - 0x7000 - 8; + gdb::byte_vector buf (gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT); + if (target_read_memory (dtv_ptr_addr, buf.data (), buf.size ()) != 0) + throw_error (TLS_GENERIC_ERROR, _("Unable to fetch DTV address")); + + const struct builtin_type *builtin = builtin_type (gdbarch); + CORE_ADDR dtv_addr = gdbarch_pointer_to_address + (gdbarch, builtin->builtin_data_ptr, buf.data ()); + return dtv_addr; +} + +/* For internal TLS lookup, return the DTP offset, which is the offset + to subtract from a DTV entry, in order to obtain the address of the + TLS block. */ + +static ULONGEST +ppc_linux_get_tls_dtp_offset (struct gdbarch *gdbarch, ptid_t ptid, + svr4_tls_libc libc) +{ + if (libc == svr4_tls_libc_musl) + { + /* This value is DTP_OFFSET, which represents the value to + subtract from the DTV entry. For PPC, it can be found in + MUSL's arch/powerpc64/pthread_arch.h and + arch/powerpc32/pthread_arch.h. (Both values are the same.) + It represents the value to subtract from the DTV entry, once + it has been fetched from the DTV array. */ + return 0x8000; + } + else + return 0; +} + static displaced_step_prepare_status ppc_linux_displaced_step_prepare (gdbarch *arch, thread_info *thread, CORE_ADDR &displaced_pc) @@ -2284,6 +2342,11 @@ ppc_linux_init_abi (struct gdbarch_info info, set_gdbarch_gnu_triplet_regexp (gdbarch, ppc64_gnu_triplet_regexp); /* Set GCC target options. */ set_gdbarch_gcc_target_options (gdbarch, ppc64_linux_gcc_target_options); + /* Internal thread local address support. */ + set_gdbarch_get_thread_local_address (gdbarch, + svr4_tls_get_thread_local_address); + svr4_tls_register_tls_methods (info, gdbarch, ppc64_linux_get_tls_dtv_addr, + ppc_linux_get_tls_dtp_offset); } set_gdbarch_core_read_description (gdbarch, ppc_linux_core_read_description); |