* mips-linux-tdep.c (mips_linux_syscall_next_pc): New function.

	(mips_linux_init_abi): Set tdep->syscall_next_pc.
	* mips-tdep.c (enum mips_fpu_type, struct gdbarch_tdep): Move to
	mips-tdep.h.
	(mips32_next_pc): Handle the syscall instruction.
	* mips-tdep.h (enum mips_fpu_type, struct gdbarch_tdep): New,
	from mips-tdep.c.  Add syscall_next_pc to gdbarch_tdep.

1 files changed, 22 insertions, 0 deletions

diff --git a/gdb/mips-linux-tdep.c b/gdb/mips-linux-tdep.c
index d631a7b3c32..8f30aef45ff 100644
--- a/gdb/mips-linux-tdep.c
+++ b/gdb/mips-linux-tdep.c
@@ -1101,6 +1101,26 @@ mips_linux_restart_reg_p (struct gdbarch *gdbarch)
   return register_size (gdbarch, MIPS_RESTART_REGNUM) > 0;
 }
 
+/* When FRAME is at a syscall instruction, return the PC of the next
+   instruction to be executed.  */
+
+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_pc_unwind (get_current_frame ());
+
+  return pc + 4;
+}
+
 /* Initialize one of the GNU/Linux OS ABIs.  */
 
 static void
@@ -1175,6 +1195,8 @@ mips_linux_init_abi (struct gdbarch_info info,
   set_gdbarch_core_read_description (gdbarch,
 				     mips_linux_core_read_description);
 
+  tdep->syscall_next_pc = mips_linux_syscall_next_pc;
+
   if (tdesc_data)
     {
       const struct tdesc_feature *feature;