AM30/AM33: move SP adds into a separate pattern

[Alexandre Oliva <aoliva at cygnus dot com>]

This patch simplifies the handling of SP adds.  Previously, the movsi
expand would explicitly request a new register to add non-constant
values to SP.  This step doesn't appear to be necessary, and removing
it actually slightly improves the generated code:

^ gcc/am33/libgcc.a 26953 26955
v gcc/libgcc.a 27027 27022
v mn10300-elf/am33/libio/libiostream.a 64000 63981
v mn10300-elf/am33/libstdc++/libstdc++.a 69862 69843

I also move SP adds to a separate pattern, since it makes the code
simpler.  Ok to install?

Index: gcc/ChangeLog
from  Alexandre Oliva  <aoliva@cygnus.com>

	* config/mn10300/mn10300.md (addsi): Remove special handling of SP
	adds from define_expand.  Move SP add to separate define_insn.

Index: gcc/config/mn10300/mn10300.md
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/mn10300/mn10300.md,v
retrieving revision 1.28
diff -u -r1.28 mn10300.md
--- gcc/config/mn10300/mn10300.md	2000/04/21 21:14:13	1.28
+++ gcc/config/mn10300/mn10300.md	2000/04/21 21:58:28
@@ -744,25 +744,19 @@
 	(plus:SI (match_operand:SI 1 "register_operand" "")
 		 (match_operand:SI 2 "nonmemory_operand" "")))]
   ""
-  "
-{
-  /* We can't add a variable amount directly to the stack pointer;
-     so do so via a temporary register.  */
-  if (operands[0] == stack_pointer_rtx
-      && GET_CODE (operands[1]) != CONST_INT
-      && GET_CODE (operands[2]) != CONST_INT)
-   {
-     rtx temp = gen_reg_rtx (SImode);
-     emit_move_insn (temp, gen_rtx_PLUS (SImode, operands[1], operands[2]));
-     emit_move_insn (operands[0], temp);
-     DONE;
-   }
-}")
+  "")
+
+(define_insn ""
+  [(set (match_operand:SI 0 "register_operand" "=y")
+	(plus:SI (match_dup 0) (match_operand:SI 1 "immediate_operand" "i")))]
+  "operands[0] == stack_pointer_rtx"
+  "add %1, %0"
+  [(set_attr "cc" "none_0hit")])
 
 (define_insn ""
-  [(set (match_operand:SI 0 "register_operand" "=dx,ax,ax,dax,xy,!dax")
-	(plus:SI (match_operand:SI 1 "register_operand" "%0,0,0,0,0,dax")
-		 (match_operand:SI 2 "nonmemory_operand" "J,J,L,daxi,i,dax")))]
+  [(set (match_operand:SI 0 "register_operand" "=dx,ax,ax,dax,!dax")
+	(plus:SI (match_operand:SI 1 "register_operand" "%0,0,0,0,dax")
+		 (match_operand:SI 2 "nonmemory_operand" "J,J,L,daxi,dax")))]
   "TARGET_AM33"
   "*
 {
@@ -774,9 +768,8 @@
     case 2:
       return \"inc4 %0\";
     case 3:
-    case 4:
       return \"add %2,%0\";
-    case 5:
+    case 4:
       {
 	enum reg_class src1_class, src2_class, dst_class;
 
@@ -835,12 +828,12 @@
       abort();
     }
 }"
-  [(set_attr "cc" "set_zn,none_0hit,none_0hit,set_zn,none_0hit,set_zn")])
+  [(set_attr "cc" "set_zn,none_0hit,none_0hit,set_zn,set_zn")])
 
 (define_insn ""
-  [(set (match_operand:SI 0 "register_operand" "=dx,ax,ax,dax,xy,!dax")
-	(plus:SI (match_operand:SI 1 "register_operand" "%0,0,0,0,0,dax")
-		 (match_operand:SI 2 "nonmemory_operand" "J,J,L,daxi,i,dax")))]
+  [(set (match_operand:SI 0 "register_operand" "=dx,ax,ax,dax,!dax")
+	(plus:SI (match_operand:SI 1 "register_operand" "%0,0,0,0,dax")
+		 (match_operand:SI 2 "nonmemory_operand" "J,J,L,daxi,dax")))]
   ""
   "*
 {
@@ -852,9 +845,8 @@
     case 2:
       return \"inc4 %0\";
     case 3:
-    case 4:
       return \"add %2,%0\";
-    case 5:
+    case 4:
       /* I'm not sure if this can happen or not.  Might as well be prepared
 	 and generate the best possible code if it does happen.  */
       if (true_regnum (operands[0]) == true_regnum (operands[1]))
@@ -877,7 +869,7 @@
       abort();
     }
 }"
-  [(set_attr "cc" "set_zn,none_0hit,none_0hit,set_zn,none_0hit,set_zn")])
+  [(set_attr "cc" "set_zn,none_0hit,none_0hit,set_zn,set_zn")])
 
 ;; ----------------------------------------------------------------------
 ;; SUBTRACT INSTRUCTIONS

-- 
Alexandre Oliva    Enjoy Guaranį, see http://www.ic.unicamp.br/~oliva/
Cygnus Solutions, a Red Hat company        aoliva@{redhat, cygnus}.com
Free Software Developer and Evangelist    CS PhD student at IC-Unicamp
oliva@{lsd.ic.unicamp.br, gnu.org}   Write to mailing lists, not to me