m68k-protos.h: Rename m68k_interrupt_function_p to m68k_get_function_kind.

gcc/
	* config/m68k/m68k-protos.h: Rename m68k_interrupt_function_p
	to m68k_get_function_kind.  Update its prototype.
	* config/m68k/m68k.c (m68k_attribute_table): Add an entry for
	interrupt_thread.
	(m68k_interrupt_function_p): Return enum m68k_function_type
	instead of bool.  Rename to m68k_get_function_kind.
	(m68k_handle_fndecl_attribute): Reject interrupt_thread if the
	target is not fido.
	(m68k_compute_frame_layout): Don't mark any register for save
	if an interrupt_thread attribute is specified.
	(m68k_hard_regno_rename_ok): Update a use of
	m68k_interrupt_function_p.
	* config/m68k/m68k.h (EPILOGUE_USES): Update a use of
	m68k_interrupt_function_p.
	(m68k_function_type): New.
	* config/m68k/m68k.md (*return): Output a 'sleep' instruction
	for a function with an interrupt_thread attribute.
	* doc/extend.texi: Document the interrupt_thread attribute.

gcc/testsuite/
	* gcc.target/m68k/interrupt_thread-1.c,
	gcc.target/m68k/interrupt_thread-2.c,
	gcc.target/m68k/interrupt_thread-3.c: New.
	* gcc.target/m68k/m68k.exp: Accept fido.

From-SVN: r124713

4 files changed, 78 insertions, 29 deletions

diff --git a/gcc/config/m68k/m68k-protos.h b/gcc/config/m68k/m68k-protos.h
index b3b78a1..f5d6c3a 100644
--- a/gcc/config/m68k/m68k-protos.h
+++ b/gcc/config/m68k/m68k-protos.h
@@ -21,7 +21,7 @@ Boston, MA 02110-1301, USA.  */
 /* Define functions defined in aux-output.c and used in templates.  */
 
 #ifdef RTX_CODE
-extern bool m68k_interrupt_function_p (tree);
+extern enum m68k_function_kind m68k_get_function_kind (tree);
 extern HOST_WIDE_INT m68k_initial_elimination_offset (int from, int to);
 
 extern void split_di (rtx[], int, rtx[], rtx[]);
diff --git a/gcc/config/m68k/m68k.c b/gcc/config/m68k/m68k.c
index f975e06..8766559 100644
--- a/gcc/config/m68k/m68k.c
+++ b/gcc/config/m68k/m68k.c
@@ -223,6 +223,7 @@ static const struct attribute_spec m68k_attribute_table[] =
 {
   /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
   { "interrupt_handler", 0, 0, true,  false, false, m68k_handle_fndecl_attribute },
+  { "interrupt_thread", 0, 0, true,  false, false, m68k_handle_fndecl_attribute },
   { NULL,                0, 0, false, false, false, NULL }
 };
 
@@ -633,10 +634,12 @@ m68k_cpp_cpu_family (const char *prefix)
   return concat ("__m", prefix, "_family_", m68k_cpu_entry->family, NULL);
 }
 
-/* Return nonzero if FUNC is an interrupt function as specified by the
-   "interrupt_handler" attribute.  */
-bool
-m68k_interrupt_function_p (tree func)
+/* Return m68k_fk_interrupt_handler if FUNC has an "interrupt_handler"
+   attribute and interrupt_thread if FUNC has an "interrupt_thread"
+   attribute.  Otherwise, return m68k_fk_normal_function.  */
+
+enum m68k_function_kind
+m68k_get_function_kind (tree func)
 {
   tree a;
 
@@ -644,7 +647,14 @@ m68k_interrupt_function_p (tree func)
     return false;
 
   a = lookup_attribute ("interrupt_handler", DECL_ATTRIBUTES (func));
-  return (a != NULL_TREE);
+  if (a != NULL_TREE)
+    return m68k_fk_interrupt_handler;
+
+  a = lookup_attribute ("interrupt_thread", DECL_ATTRIBUTES (func));
+  if (a != NULL_TREE)
+    return m68k_fk_interrupt_thread;
+
+  return m68k_fk_normal_function;
 }
 
 /* Handle an attribute requiring a FUNCTION_DECL; arguments as in
@@ -662,6 +672,19 @@ m68k_handle_fndecl_attribute (tree *node, tree name,
       *no_add_attrs = true;
     }
 
+  if (m68k_get_function_kind (*node) != m68k_fk_normal_function)
+    {
+      error ("multiple interrupt attributes not allowed");
+      *no_add_attrs = true;
+    }
+
+  if (!TARGET_FIDOA
+      && !strcmp (IDENTIFIER_POINTER (name), "interrupt_thread"))
+    {
+      error ("interrupt_thread is available only on fido");
+      *no_add_attrs = true;
+    }
+
   return NULL_TREE;
 }
 
@@ -670,7 +693,10 @@ m68k_compute_frame_layout (void)
 {
   int regno, saved;
   unsigned int mask;
-  bool interrupt_handler = m68k_interrupt_function_p (current_function_decl);
+  enum m68k_function_kind func_kind =
+    m68k_get_function_kind (current_function_decl);
+  bool interrupt_handler = func_kind == m68k_fk_interrupt_handler;
+  bool interrupt_thread = func_kind == m68k_fk_interrupt_thread;
 
   /* Only compute the frame once per function.
      Don't cache information until reload has been completed.  */
@@ -681,12 +707,15 @@ m68k_compute_frame_layout (void)
   current_frame.size = (get_frame_size () + 3) & -4;
 
   mask = saved = 0;
-  for (regno = 0; regno < 16; regno++)
-    if (m68k_save_reg (regno, interrupt_handler))
-      {
-	mask |= 1 << (regno - D0_REG);
-	saved++;
-      }
+
+  /* Interrupt thread does not need to save any register.  */
+  if (!interrupt_thread)
+    for (regno = 0; regno < 16; regno++)
+      if (m68k_save_reg (regno, interrupt_handler))
+	{
+	  mask |= 1 << (regno - D0_REG);
+	  saved++;
+	}
   current_frame.offset = saved * 4;
   current_frame.reg_no = saved;
   current_frame.reg_mask = mask;
@@ -695,12 +724,14 @@ m68k_compute_frame_layout (void)
   mask = saved = 0;
   if (TARGET_HARD_FLOAT)
     {
-      for (regno = 16; regno < 24; regno++)
-	if (m68k_save_reg (regno, interrupt_handler))
-	  {
-	    mask |= 1 << (regno - FP0_REG);
-	    saved++;
-	  }
+      /* Interrupt thread does not need to save any register.  */
+      if (!interrupt_thread)
+	for (regno = 16; regno < 24; regno++)
+	  if (m68k_save_reg (regno, interrupt_handler))
+	    {
+	      mask |= 1 << (regno - FP0_REG);
+	      saved++;
+	    }
       current_frame.foffset = saved * TARGET_FP_REG_SIZE;
       current_frame.offset += current_frame.foffset;
     }
@@ -4211,7 +4242,8 @@ m68k_hard_regno_rename_ok (unsigned int old_reg ATTRIBUTE_UNUSED,
      saved by the prologue, even if they would normally be
      call-clobbered.  */
 
-  if (m68k_interrupt_function_p (current_function_decl)
+  if ((m68k_get_function_kind (current_function_decl)
+       == m68k_fk_interrupt_handler)
       && !regs_ever_live[new_reg])
     return 0;
 
diff --git a/gcc/config/m68k/m68k.h b/gcc/config/m68k/m68k.h
index baa5bcb..1b19b4c 100644
--- a/gcc/config/m68k/m68k.h
+++ b/gcc/config/m68k/m68k.h
@@ -903,8 +903,10 @@ do { if (cc_prev_status.flags & CC_IN_68881)			\
 #define INCOMING_FRAME_SP_OFFSET 4
 
 /* All registers are live on exit from an interrupt routine.  */
-#define EPILOGUE_USES(REGNO) \
-  (reload_completed && m68k_interrupt_function_p (current_function_decl))
+#define EPILOGUE_USES(REGNO)					\
+  (reload_completed						\
+   && (m68k_get_function_kind (current_function_decl)	\
+       == m68k_fk_interrupt_handler))
 
 /* Describe how we implement __builtin_eh_return.  */
 #define EH_RETURN_DATA_REGNO(N) \
@@ -1098,6 +1100,13 @@ enum fpu_type
   FPUTYPE_COLDFIRE
 };
 
+enum m68k_function_kind
+{
+  m68k_fk_normal_function,
+  m68k_fk_interrupt_handler,
+  m68k_fk_interrupt_thread
+};
+
 /* Variables in m68k.c; see there for details.  */
 extern const char *m68k_library_id_string;
 extern int m68k_last_compare_had_fp_operands;
diff --git a/gcc/config/m68k/m68k.md b/gcc/config/m68k/m68k.md
index 78ddf58..19abe62 100644
--- a/gcc/config/m68k/m68k.md
+++ b/gcc/config/m68k/m68k.md
@@ -6833,15 +6833,23 @@
   [(return)]
   ""
 {
-  if (m68k_interrupt_function_p (current_function_decl))
-    return "rte";
-  else if (current_function_pops_args)
+  switch (m68k_get_function_kind (current_function_decl))
     {
-      operands[0] = GEN_INT (current_function_pops_args);
-      return "rtd %0";
+    case m68k_fk_interrupt_handler:
+      return "rte";
+
+    case m68k_fk_interrupt_thread:
+      return "sleep";
+
+    default:
+      if (current_function_pops_args)
+	{
+	  operands[0] = GEN_INT (current_function_pops_args);
+	  return "rtd %0";
+	}
+      else
+	return "rts";
     }
-  else
-    return "rts";
 })
 
 (define_insn "*m68k_store_multiple"