+/* Set the program counter for process PTID to PC. */
+
+#define TSTATE_SYSCALL 0x0000000000000020ULL
+
+static void
+sparc64_linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
+ ULONGEST state;
+
+ regcache_cooked_write_unsigned (regcache, tdep->pc_regnum, pc);
+ regcache_cooked_write_unsigned (regcache, tdep->npc_regnum, pc + 4);
+
+ /* Clear the "in syscall" bit to prevent the kernel from
+ messing with the PCs we just installed, if we happen to be
+ within an interrupted system call that the kernel wants to
+ restart.
+
+ Note that after we return from the dummy call, the TSTATE et al.
+ registers will be automatically restored, and the kernel
+ continues to restart the system call at this point. */
+ regcache_cooked_read_unsigned (regcache, SPARC64_STATE_REGNUM, &state);
+ state &= ~TSTATE_SYSCALL;
+ regcache_cooked_write_unsigned (regcache, SPARC64_STATE_REGNUM, state);
+}
+
+static LONGEST
+sparc64_linux_get_syscall_number (struct gdbarch *gdbarch,
+ ptid_t ptid)
+{
+ struct regcache *regcache = get_thread_regcache (ptid);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ /* The content of a register. */
+ gdb_byte buf[8];
+ /* The result. */
+ LONGEST ret;
+
+ /* Getting the system call number from the register.
+ When dealing with the sparc architecture, this information
+ is stored at the %g1 register. */
+ regcache_cooked_read (regcache, SPARC_G1_REGNUM, buf);
+
+ ret = extract_signed_integer (buf, 8, byte_order);
+
+ return ret;
+}
+