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Diffstat (limited to 'gdb/s390-linux-tdep.c')
-rw-r--r--gdb/s390-linux-tdep.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
index 04c523b..bd1f42c 100644
--- a/gdb/s390-linux-tdep.c
+++ b/gdb/s390-linux-tdep.c
@@ -29,6 +29,7 @@
#include "gdbcore.h"
#include "linux-record.h"
#include "linux-tdep.h"
+#include "svr4-tls-tdep.h"
#include "objfiles.h"
#include "osabi.h"
#include "regcache.h"
@@ -40,6 +41,7 @@
#include "target.h"
#include "trad-frame.h"
#include "xml-syscall.h"
+#include "inferior.h"
#include "features/s390-linux32v1.c"
#include "features/s390-linux32v2.c"
@@ -1124,6 +1126,45 @@ s390_init_linux_record_tdep (struct linux_record_tdep *record_tdep,
record_tdep->ioctl_FIOQSIZE = 0x545e;
}
+/* Fetch and return the TLS DTV (dynamic thread vector) address for PTID.
+ Throw a suitable TLS error if something goes wrong. */
+
+static CORE_ADDR
+s390_linux_get_tls_dtv_addr (struct gdbarch *gdbarch, ptid_t ptid,
+ enum svr4_tls_libc libc)
+{
+ /* On S390, the thread pointer is found in two registers A0 and A1
+ (or, using gdb naming, acr0 and acr1) A0 contains the top 32
+ bits of the address and A1 contains the bottom 32 bits. */
+ regcache *regcache
+ = get_thread_arch_regcache (current_inferior (), ptid, gdbarch);
+ target_fetch_registers (regcache, S390_A0_REGNUM);
+ target_fetch_registers (regcache, S390_A1_REGNUM);
+ ULONGEST thr_ptr_lo, thr_ptr_hi, thr_ptr;
+ if (regcache->cooked_read (S390_A0_REGNUM, &thr_ptr_hi) != REG_VALID
+ || regcache->cooked_read (S390_A1_REGNUM, &thr_ptr_lo) != REG_VALID)
+ throw_error (TLS_GENERIC_ERROR, _("Unable to fetch thread pointer"));
+ thr_ptr = (thr_ptr_hi << 32) + thr_ptr_lo;
+
+ /* The thread pointer points at the TCB (thread control block). The
+ first two members of this struct are both pointers, where the
+ first will be a pointer to the TCB (i.e. it points at itself)
+ and the second will be a pointer to the DTV (dynamic thread
+ vector). There are many other fields too, but the one we care
+ about here is the DTV pointer. Compute the address of the DTV
+ pointer, fetch it, and convert it to an address. */
+ CORE_ADDR dtv_ptr_addr
+ = thr_ptr + gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT;
+ 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;
+}
+
/* Initialize OSABI common for GNU/Linux on 31- and 64-bit systems. */
static void
@@ -1152,6 +1193,9 @@ s390_linux_init_abi_any (struct gdbarch_info info, struct gdbarch *gdbarch)
/* Enable TLS support. */
set_gdbarch_fetch_tls_load_module_address (gdbarch,
svr4_fetch_objfile_link_map);
+ set_gdbarch_get_thread_local_address (gdbarch,
+ svr4_tls_get_thread_local_address);
+ svr4_tls_register_tls_methods (info, gdbarch, s390_linux_get_tls_dtv_addr);
/* Support reverse debugging. */
set_gdbarch_process_record_signal (gdbarch, s390_linux_record_signal);