coff.h (REGISTER_NAMES): Add fake register `argptr'

	* config/m68k/coff.h (REGISTER_NAMES): Add fake register `argptr'
	* config/m68k/hp320.h (REGISTER_NAMES): Likewise.
	* config/m68k/linux.h (REGISTER_NAMES): Likewise.
	* config/m68k/m68kelf.h (REGISTER_NAMES): Likewise.
	* gcc/config/m68k/sgs.h (REGISTER_NAMES): Likewise.
	* config/m68k/m68k-protos.h (m68k_initial_elimination_offset): Add prototype.
	* config/m68k/m68k.c (m68k_frame): New struct, simular to ix86 back-end.
	(m68k_compute_frame_layout): New function.
	(m68k_initial_elimination_offset): New function.
	(m68k_output_function_prologue): ColdFire-specific movem handling.
	(m68k_output_function_epilogue): Likewise.
	* config/m68k/m68k.h (FIRST_PSEOUDO_REGISTER): Make room for argptr reg.
	(ARG_POINTER_REGNUM): Add new definition.
	(INITIAL_FRAME_POINTER_OFFSET): Remove macro.
	(ELIMINABLE_REGS): Define new macro, like in ix86 back-end.
	(CAN_ELIMINATE): Likewise.
	(INITIAL_ELIMINATION_OFFSET): Likewise.

Co-Authored-By: Peter Barada <peter@baradas.org>

From-SVN: r71231

gcc/ChangeLog

 2003-09-08  Bernardo Innocenti  <bernie@develer.com>
+            Peter Barada <peter@baradas.org>
+
+	* config/m68k/coff.h (REGISTER_NAMES): Add fake register `argptr'
+	* config/m68k/hp320.h (REGISTER_NAMES): Likewise.
+	* config/m68k/linux.h (REGISTER_NAMES): Likewise.
+	* config/m68k/m68kelf.h (REGISTER_NAMES): Likewise.
+	* gcc/config/m68k/sgs.h (REGISTER_NAMES): Likewise.
+	* config/m68k/m68k-protos.h (m68k_initial_elimination_offset): Add prototype.
+	* config/m68k/m68k.c (m68k_frame): New struct, simular to ix86 back-end.
+	(m68k_compute_frame_layout): New function.
+	(m68k_initial_elimination_offset): New function.
+	(m68k_output_function_prologue): ColdFire-specific movem handling.
+	(m68k_output_function_epilogue): Likewise.
+	* config/m68k/m68k.h (FIRST_PSEOUDO_REGISTER): Make room for argptr reg.
+	(ARG_POINTER_REGNUM): Add new definition.
+	(INITIAL_FRAME_POINTER_OFFSET): Remove macro.
+	(ELIMINABLE_REGS): Define new macro, like in ix86 back-end.
+	(CAN_ELIMINATE): Likewise.
+	(INITIAL_ELIMINATION_OFFSET): Likewise.
+
+2003-09-08  Bernardo Innocenti  <bernie@develer.com>
 
 	* config/m68k/m68k.c (m68k_output_function_prologue): Simplify
 	by removing redundant variable cfa_store_offset.

gcc/config/m68k/coff.h

@@ -74,7 +74,7 @@ Boston, MA 02111-1307, USA.  */
 #define REGISTER_NAMES \
 {"%d0", "%d1", "%d2", "%d3", "%d4", "%d5", "%d6", "%d7",	\
  "%a0", "%a1", "%a2", "%a3", "%a4", "%a5", "%a6", "%sp",	\
- "%fp0", "%fp1", "%fp2", "%fp3", "%fp4", "%fp5", "%fp6", "%fp7" }
+ "%fp0", "%fp1", "%fp2", "%fp3", "%fp4", "%fp5", "%fp6", "%fp7", "argptr" }
 
 #define TARGET_ASM_FILE_START_FILE_DIRECTIVE true
 

gcc/config/m68k/hp320.h

@@ -158,7 +158,7 @@ Boston, MA 02111-1307, USA.  */
 #define REGISTER_NAMES \
 {"%d0", "%d1", "%d2", "%d3", "%d4", "%d5", "%d6", "%d7",	\
  "%a0", "%a1", "%a2", "%a3", "%a4", "%a5", "%fp", "%sp",	\
- "%fp0", "%fp1", "%fp2", "%fp3", "%fp4", "%fp5", "%fp6", "%fp7"}
+ "%fp0", "%fp1", "%fp2", "%fp3", "%fp4", "%fp5", "%fp6", "%fp7", "argptr"}
 
 #define IMMEDIATE_PREFIX        "&"
 #define REGISTER_PREFIX         "%"

gcc/config/m68k/linux.h

@@ -68,7 +68,7 @@ Boston, MA 02111-1307, USA.  */
 #define REGISTER_NAMES \
 {"%d0", "%d1", "%d2", "%d3", "%d4", "%d5", "%d6", "%d7", \
  "%a0", "%a1", "%a2", "%a3", "%a4", "%a5", "%a6", "%sp", \
- "%fp0", "%fp1", "%fp2", "%fp3", "%fp4", "%fp5", "%fp6", "%fp7" }
+ "%fp0", "%fp1", "%fp2", "%fp3", "%fp4", "%fp5", "%fp6", "%fp7", "argptr" }
 
 #undef SIZE_TYPE
 #define SIZE_TYPE "unsigned int"

gcc/config/m68k/m68k-protos.h

@@ -21,6 +21,7 @@ Boston, MA 02111-1307, USA.  */
 /* Define functions defined in aux-output.c and used in templates.  */
 
 #ifdef RTX_CODE
+extern HOST_WIDE_INT m68k_initial_elimination_offset (int from, int to);
 extern const char *output_move_const_into_data_reg (rtx *);
 extern const char *output_move_simode_const (rtx *);
 extern const char *output_move_simode (rtx *);

gcc/config/m68k/m68k.h

@@ -386,7 +386,7 @@ extern int target_flags;
    For the 68000, we give the data registers numbers 0-7,
    the address registers numbers 010-017,
    and the 68881 floating point registers numbers 020-027.  */
-#define FIRST_PSEUDO_REGISTER 24
+#define FIRST_PSEUDO_REGISTER 25
 
 /* This defines the register which is used to hold the offset table for PIC.  */
 #define PIC_OFFSET_TABLE_REGNUM (flag_pic ? 13 : INVALID_REGNUM)
@@ -493,8 +493,11 @@ extern int target_flags;
    This is computed in `reload', in reload1.c.  */
 #define FRAME_POINTER_REQUIRED 0
 
-/* Base register for access to arguments of the function.  */
-#define ARG_POINTER_REGNUM 14
+/* Base register for access to arguments of the function.
+ * This isn't a hardware register. It will be eliminated to the
+ * stack pointer or frame pointer.
+ */
+#define ARG_POINTER_REGNUM 24
 
 /* Register in which static-chain is passed to a function.  */
 #define STATIC_CHAIN_REGNUM 8
@@ -879,32 +882,6 @@ enum reg_class {
    You should override this if you define FUNCTION_EXTRA_EPILOGUE.  */
 #define USE_RETURN_INSN use_return_insn ()
 
-/* Store in the variable DEPTH the initial difference between the
-   frame pointer reg contents and the stack pointer reg contents,
-   as of the start of the function body.  This depends on the layout
-   of the fixed parts of the stack frame and on how registers are saved.
-
-   On the 68k, if we have a frame, we must add one word to its length
-   to allow for the place that a6 is stored when we do have a frame pointer.
-   Otherwise, we would need to compute the offset from the frame pointer
-   of a local variable as a function of frame_pointer_needed, which
-   is hard.  */
-
-#define INITIAL_FRAME_POINTER_OFFSET(DEPTH)			\
-{ int regno;							\
-  int offset = -4;						\
-  for (regno = 16; regno < FIRST_PSEUDO_REGISTER; regno++)	\
-    if (regs_ever_live[regno] && ! call_used_regs[regno])	\
-      offset += 12;						\
-  for (regno = 0; regno < 16; regno++)				\
-    if (regs_ever_live[regno] && ! call_used_regs[regno])	\
-      offset += 4;						\
-  if (flag_pic && current_function_uses_pic_offset_table)	\
-    offset += 4;						\
-  (DEPTH) = (offset + ((get_frame_size () + 3) & -4)		\
-	     + (get_frame_size () == 0 ? 0 : 4));		\
-}
-
 /* Output assembler code for a block containing the constant parts
    of a trampoline, leaving space for the variable parts.  */
 
@@ -982,6 +959,38 @@ __transfer_from_trampoline ()					\
   asm ("rts":);							\
 }
 
+/* Definitions for register eliminations.
+
+   This is an array of structures.  Each structure initializes one pair
+   of eliminable registers.  The "from" register number is given first,
+   followed by "to".  Eliminations of the same "from" register are listed
+   in order of preference.
+
+   There are two registers that can always be eliminated on the m68k.
+   The frame pointer and the arg pointer can be replaced by either the
+   hard frame pointer or to the stack pointer, depending upon the
+   circumstances.  The hard frame pointer is not used before reload and
+   so it is not eligible for elimination.  */
+
+#define ELIMINABLE_REGS					\
+{{ ARG_POINTER_REGNUM, STACK_POINTER_REGNUM },		\
+ { ARG_POINTER_REGNUM, FRAME_POINTER_REGNUM },	\
+ { FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM }}
+
+/* Given FROM and TO register numbers, say whether this elimination is
+   allowed.  Frame pointer elimination is automatically handled.
+
+   All other eliminations are valid.  */
+
+#define CAN_ELIMINATE(FROM, TO) \
+  ((TO) == STACK_POINTER_REGNUM ? ! frame_pointer_needed : 1)
+
+/* Define the offset between two registers, one to be eliminated, and the other
+   its replacement, at the start of a routine.  */
+
+#define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET)			\
+  (OFFSET) = m68k_initial_elimination_offset(FROM, TO)
+
 /* Addressing modes, and classification of registers for them.  */
 
 #define HAVE_POST_INCREMENT 1
@@ -1381,7 +1390,7 @@ __transfer_from_trampoline ()					\
 #define REGISTER_NAMES \
 {"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7",	\
  "a0", "a1", "a2", "a3", "a4", "a5", "a6", "sp",	\
- "fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7" }
+ "fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7", "argptr" }
 
 /* How to renumber registers for dbx and gdb.
    On the Sun-3, the floating point registers have numbers

gcc/config/m68k/m68kelf.h

@@ -94,7 +94,7 @@ Boston, MA 02111-1307, USA.  */
 #define REGISTER_NAMES \
 {"%d0",   "%d1",   "%d2",   "%d3",   "%d4",   "%d5",   "%d6",   "%d7",	     \
  "%a0",   "%a1",   "%a2",   "%a3",   "%a4",   "%a5",   "%a6",   "%sp",	     \
- "%fp0",  "%fp1",  "%fp2",  "%fp3",  "%fp4",  "%fp5",  "%fp6",  "%fp7" }
+ "%fp0",  "%fp1",  "%fp2",  "%fp3",  "%fp4",  "%fp5",  "%fp6",  "%fp7", "argptr" }
 
 /* This is how to output an assembler line that says to advance the
    location counter to a multiple of 2**LOG bytes.  */

gcc/config/m68k/sgs.h

@@ -72,7 +72,7 @@ Boston, MA 02111-1307, USA.  */
 #define REGISTER_NAMES \
 {"%d0",   "%d1",   "%d2",   "%d3",   "%d4",   "%d5",   "%d6",   "%d7",	     \
  "%a0",   "%a1",   "%a2",   "%a3",   "%a4",   "%a5",   "%fp",   "%sp",	     \
- "%fp0",  "%fp1",  "%fp2",  "%fp3",  "%fp4",  "%fp5",  "%fp6",  "%fp7" }
+ "%fp0",  "%fp1",  "%fp2",  "%fp3",  "%fp4",  "%fp5",  "%fp6",  "%fp7", "argptr" }
 
 /* This is how to output an assembler line that says to advance the
    location counter to a multiple of 2**LOG bytes.  */