2007-08-27 Sandra Loosemore <sandra@codesourcery.com>

	    David Ung  <davidu@mips.com>
            Nigel Stephens <nigel@mips.com>

	gcc/
	Separate target-specific initialization from general
	back-end initialization.

	* toplev.c (init_alignments): New, split out from...
	(process_options): ...here.
	(backend_init_target):  New, split out from...
	(backend_init): ...here.
	(lang_dependent_init_target):  New, split out from...
	(lang_dependent_init): ...here.
	(target_reinit): New.
	* toplev.h (target_reinit): Declare.
	* expr.c (init_expr_target): Renamed from init_expr_once, since it
	now can be called more than once.  Update comments.
	* expr.h (init_expr_target): Likewise.
	* alias.c (init_alias_target): Renamed from init_alias_once, since it
	now can be called more than once.  Explicitly zero
	static_reg_base_value.
	* emit-rtl.c (init_emit_regs): New, split out from...
	(init_emit_once): Here.
	* regclass.c (initial_fixed_regs, initial_call_used_regs): Make
	non-const, so that changes from command-line arguments can overwrite
	values provided by the static initializers.
	(initial_call_really_used_regs): New, used similarly to the above.
	(initial_reg_names): Likewise.
	(last_mode_for_init_move_cost): Promoted function-local static to
	file-scope static to make it accessible outside init_move_cost.
	(init_reg_sets): Do not initialize fixed_regs and call_used_regs yet.
	Do not initialize inv_reg_alloc_order yet, either.  Do initialize
	reg_names since it is needed for parsing command-line options.
	(init_move_cost): Use last_mode_for_init_move_cost instead of
	function-local static.
	(init_reg_sets_1): Initialize fixed_regs, call_used_regs, and
	call_really_used_regs now.  Reinitialize reg_names.  Also
	initialize inv_reg_alloc_order.  Zero reg_class_subunion and
	reg_class_superunion.  Clear losing_caller_save_reg_set.
	Preserve global registers if called more than once.  Reset
	move cost, may_move_in_cost, may_move_out_cost, and
	last_mode_for_init_move_cost.
	(init_reg_modes_target): Renamed from init_reg_modes_once, since it
	can now be invoked more than once.  Update comments.
	(init_regs): Update comments.
	(fix_register): Update initial_fixed_regs, initial_call_used_regs,
	and initial_call_really_used_regs, instead of the non-initial 
        variables.  This allows us to save the command-line register settings
	after target reinitialization.
	(init_reg_autoinc): Zero forbidden_inc_dec_classes.
	* rtl.h (init_emit_regs): Declare.
	(init_reg_modes_target, init_alias_target): Renamed as described
	above.
	* reload1.c (init_reload): Update comments.
	* optabs.c (init_optabs): Likewise.
	* cfgloopanal.c (init_set_costs): Explicitly zero target_avail_regs.
	



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@127832 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 68 insertions, 61 deletions

diff --git a/gcc/emit-rtl.c b/gcc/emit-rtl.c
index 32dce933290..6a4604d40e9 100644
--- a/gcc/emit-rtl.c
+++ b/gcc/emit-rtl.c
@@ -5260,6 +5260,74 @@ gen_rtx_CONST_VECTOR (enum machine_mode mode, rtvec v)
   return gen_rtx_raw_CONST_VECTOR (mode, v);
 }
 
+/* Initialise global register information required by all functions.  */
+
+void
+init_emit_regs (void)
+{
+  int i;
+
+  /* Reset register attributes */
+  htab_empty (reg_attrs_htab);
+
+  /* We need reg_raw_mode, so initialize the modes now.  */
+  init_reg_modes_target ();
+
+  /* Assign register numbers to the globally defined register rtx.  */
+  pc_rtx = gen_rtx_PC (VOIDmode);
+  cc0_rtx = gen_rtx_CC0 (VOIDmode);
+  stack_pointer_rtx = gen_raw_REG (Pmode, STACK_POINTER_REGNUM);
+  frame_pointer_rtx = gen_raw_REG (Pmode, FRAME_POINTER_REGNUM);
+  hard_frame_pointer_rtx = gen_raw_REG (Pmode, HARD_FRAME_POINTER_REGNUM);
+  arg_pointer_rtx = gen_raw_REG (Pmode, ARG_POINTER_REGNUM);
+  virtual_incoming_args_rtx =
+    gen_raw_REG (Pmode, VIRTUAL_INCOMING_ARGS_REGNUM);
+  virtual_stack_vars_rtx =
+    gen_raw_REG (Pmode, VIRTUAL_STACK_VARS_REGNUM);
+  virtual_stack_dynamic_rtx =
+    gen_raw_REG (Pmode, VIRTUAL_STACK_DYNAMIC_REGNUM);
+  virtual_outgoing_args_rtx =
+    gen_raw_REG (Pmode, VIRTUAL_OUTGOING_ARGS_REGNUM);
+  virtual_cfa_rtx = gen_raw_REG (Pmode, VIRTUAL_CFA_REGNUM);
+
+  /* Initialize RTL for commonly used hard registers.  These are
+     copied into regno_reg_rtx as we begin to compile each function.  */
+  for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+    static_regno_reg_rtx[i] = gen_raw_REG (reg_raw_mode[i], i);
+
+#ifdef RETURN_ADDRESS_POINTER_REGNUM
+  return_address_pointer_rtx
+    = gen_raw_REG (Pmode, RETURN_ADDRESS_POINTER_REGNUM);
+#endif
+
+#ifdef STATIC_CHAIN_REGNUM
+  static_chain_rtx = gen_rtx_REG (Pmode, STATIC_CHAIN_REGNUM);
+
+#ifdef STATIC_CHAIN_INCOMING_REGNUM
+  if (STATIC_CHAIN_INCOMING_REGNUM != STATIC_CHAIN_REGNUM)
+    static_chain_incoming_rtx
+      = gen_rtx_REG (Pmode, STATIC_CHAIN_INCOMING_REGNUM);
+  else
+#endif
+    static_chain_incoming_rtx = static_chain_rtx;
+#endif
+
+#ifdef STATIC_CHAIN
+  static_chain_rtx = STATIC_CHAIN;
+
+#ifdef STATIC_CHAIN_INCOMING
+  static_chain_incoming_rtx = STATIC_CHAIN_INCOMING;
+#else
+  static_chain_incoming_rtx = static_chain_rtx;
+#endif
+#endif
+
+  if ((unsigned) PIC_OFFSET_TABLE_REGNUM != INVALID_REGNUM)
+    pic_offset_table_rtx = gen_raw_REG (Pmode, PIC_OFFSET_TABLE_REGNUM);
+  else
+    pic_offset_table_rtx = NULL_RTX;
+}
+
 /* Create some permanent unique rtl objects shared between all functions.
    LINE_NUMBERS is nonzero if line numbers are to be generated.  */
 
@@ -5270,9 +5338,6 @@ init_emit_once (int line_numbers)
   enum machine_mode mode;
   enum machine_mode double_mode;
 
-  /* We need reg_raw_mode, so initialize the modes now.  */
-  init_reg_modes_once ();
-
   /* Initialize the CONST_INT, CONST_DOUBLE, CONST_FIXED, and memory attribute
      hash tables.  */
   const_int_htab = htab_create_ggc (37, const_int_htab_hash,
@@ -5321,34 +5386,6 @@ init_emit_once (int line_numbers)
 
   ptr_mode = mode_for_size (POINTER_SIZE, GET_MODE_CLASS (Pmode), 0);
 
-  /* Assign register numbers to the globally defined register rtx.
-     This must be done at runtime because the register number field
-     is in a union and some compilers can't initialize unions.  */
-
-  pc_rtx = gen_rtx_PC (VOIDmode);
-  cc0_rtx = gen_rtx_CC0 (VOIDmode);
-  stack_pointer_rtx = gen_raw_REG (Pmode, STACK_POINTER_REGNUM);
-  frame_pointer_rtx = gen_raw_REG (Pmode, FRAME_POINTER_REGNUM);
-  if (hard_frame_pointer_rtx == 0)
-    hard_frame_pointer_rtx = gen_raw_REG (Pmode,
-					  HARD_FRAME_POINTER_REGNUM);
-  if (arg_pointer_rtx == 0)
-    arg_pointer_rtx = gen_raw_REG (Pmode, ARG_POINTER_REGNUM);
-  virtual_incoming_args_rtx =
-    gen_raw_REG (Pmode, VIRTUAL_INCOMING_ARGS_REGNUM);
-  virtual_stack_vars_rtx =
-    gen_raw_REG (Pmode, VIRTUAL_STACK_VARS_REGNUM);
-  virtual_stack_dynamic_rtx =
-    gen_raw_REG (Pmode, VIRTUAL_STACK_DYNAMIC_REGNUM);
-  virtual_outgoing_args_rtx =
-    gen_raw_REG (Pmode, VIRTUAL_OUTGOING_ARGS_REGNUM);
-  virtual_cfa_rtx = gen_raw_REG (Pmode, VIRTUAL_CFA_REGNUM);
-
-  /* Initialize RTL for commonly used hard registers.  These are
-     copied into regno_reg_rtx as we begin to compile each function.  */
-  for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
-    static_regno_reg_rtx[i] = gen_raw_REG (reg_raw_mode[i], i);
-
 #ifdef INIT_EXPANDERS
   /* This is to initialize {init|mark|free}_machine_status before the first
      call to push_function_context_to.  This is needed by the Chill front
@@ -5558,36 +5595,6 @@ init_emit_once (int line_numbers)
   const_tiny_rtx[0][(int) BImode] = const0_rtx;
   if (STORE_FLAG_VALUE == 1)
     const_tiny_rtx[1][(int) BImode] = const1_rtx;
-
-#ifdef RETURN_ADDRESS_POINTER_REGNUM
-  return_address_pointer_rtx
-    = gen_raw_REG (Pmode, RETURN_ADDRESS_POINTER_REGNUM);
-#endif
-
-#ifdef STATIC_CHAIN_REGNUM
-  static_chain_rtx = gen_rtx_REG (Pmode, STATIC_CHAIN_REGNUM);
-
-#ifdef STATIC_CHAIN_INCOMING_REGNUM
-  if (STATIC_CHAIN_INCOMING_REGNUM != STATIC_CHAIN_REGNUM)
-    static_chain_incoming_rtx
-      = gen_rtx_REG (Pmode, STATIC_CHAIN_INCOMING_REGNUM);
-  else
-#endif
-    static_chain_incoming_rtx = static_chain_rtx;
-#endif
-
-#ifdef STATIC_CHAIN
-  static_chain_rtx = STATIC_CHAIN;
-
-#ifdef STATIC_CHAIN_INCOMING
-  static_chain_incoming_rtx = STATIC_CHAIN_INCOMING;
-#else
-  static_chain_incoming_rtx = static_chain_rtx;
-#endif
-#endif
-
-  if ((unsigned) PIC_OFFSET_TABLE_REGNUM != INVALID_REGNUM)
-    pic_offset_table_rtx = gen_raw_REG (Pmode, PIC_OFFSET_TABLE_REGNUM);
 }
 
 /* Produce exact duplicate of insn INSN after AFTER.