+/* When FRAME is at a syscall instruction, return the PC of the next
+ instruction to be executed. */
+
+static CORE_ADDR
+mips_linux_syscall_next_pc (struct frame_info *frame)
+{
+ CORE_ADDR pc = get_frame_pc (frame);
+ ULONGEST v0 = get_frame_register_unsigned (frame, MIPS_V0_REGNUM);
+
+ /* If we are about to make a sigreturn syscall, use the unwinder to
+ decode the signal frame. */
+ if (v0 == MIPS_NR_sigreturn
+ || v0 == MIPS_NR_rt_sigreturn
+ || v0 == MIPS_NR_N64_rt_sigreturn
+ || v0 == MIPS_NR_N32_rt_sigreturn)
+ return frame_unwind_caller_pc (get_current_frame ());
+
+ return pc + 4;
+}
+
+/* Return the current system call's number present in the
+ v0 register. When the function fails, it returns -1. */
+
+static LONGEST
+mips_linux_get_syscall_number (struct gdbarch *gdbarch,
+ ptid_t ptid)
+{
+ struct regcache *regcache = get_thread_regcache (ptid);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int regsize = register_size (gdbarch, MIPS_V0_REGNUM);
+ /* The content of a register */
+ gdb_byte buf[8];
+ /* The result */
+ LONGEST ret;
+
+ /* Make sure we're in a known ABI */
+ gdb_assert (tdep->mips_abi == MIPS_ABI_O32
+ || tdep->mips_abi == MIPS_ABI_N32
+ || tdep->mips_abi == MIPS_ABI_N64);
+
+ gdb_assert (regsize <= sizeof (buf));
+
+ /* Getting the system call number from the register.
+ syscall number is in v0 or $2. */
+ regcache_cooked_read (regcache, MIPS_V0_REGNUM, buf);
+
+ ret = extract_signed_integer (buf, regsize, byte_order);
+
+ return ret;
+}
+
projects / deliverable / binutils-gdb.git / blobdiff