h8300.md (adjust_length): New attribute.

Mon Mar 22 10:44:33 1999  Vladimir Makarov  <vmakarov@tofu.to.cygnus.com>
	* config/h8300/h8300.md (adjust_length): New attribute.
 	(modhi3+1, andsi3+1, iorsi3+1, extzv+1, extzv+2): Change insn
 	default value of attribute "adjust_length" onto "no".
	* config/h8300/h8300.c (h8300_adjust_insn_length):  Use 0 if the
	shift is negative.
	* final.c (shorten_branches): Check insn length after its
 	adjusting.

From-SVN: r25895

gcc/ChangeLog

@@ -1,3 +1,15 @@
+Mon Mar 22 10:44:33 1999  Vladimir Makarov  <vmakarov@tofu.to.cygnus.com>
+
+	* config/h8300/h8300.md (adjust_length): New attribute.
+ 	(modhi3+1, andsi3+1, iorsi3+1, extzv+1, extzv+2): Change insn
+ 	default value of attribute "adjust_length" onto "no".
+
+	* config/h8300/h8300.c (h8300_adjust_insn_length):  Use 0 if the
+	shift is negative.
+
+	* final.c (shorten_branches): Check insn length after its
+ 	adjusting.
+
 Sun Mar 21 17:33:48 1999  Jeffrey A Law  (law@cygnus.com)
 
 	* i860.h (TARGET_SWITCHES): Add documentation for default case.

gcc/config/h8300/h8300.c

@@ -3031,7 +3031,12 @@ h8300_adjust_insn_length (insn, length)
      rtx insn;
      int length;
 {
-  rtx pat = PATTERN (insn);
+  rtx pat;
+
+  if (get_attr_adjust_length (insn) == ADJUST_LENGTH_NO)
+    return 0;
+
+  pat = PATTERN (insn);
 
   /* Adjust length for reg->mem and mem->reg copies.  */
   if (GET_CODE (pat) == SET
@@ -3109,34 +3114,37 @@ h8300_adjust_insn_length (insn, length)
     {
       rtx src = SET_SRC (XVECEXP (pat, 0, 0));
       enum machine_mode mode = GET_MODE (src);
+      int shift;
 
       if (GET_CODE (XEXP (src, 1)) != CONST_INT)
 	return 0;
 
+      shift = INTVAL (XEXP (src, 1));
+      /* According to ANSI, negative shift is undefined.  It is
+         considered to be zero in this case (see function
+         emit_a_shift above). */
+      if (shift < 0)
+	shift = 0;
+
       /* QImode shifts by small constants take one insn
 	 per shift.  So the adjustment is 20 (md length) -
 	 # shifts * 2.  */
-      if (mode == QImode && INTVAL (XEXP (src, 1)) <= 4)
+      if (mode == QImode && shift <= 4)
-	return -(20 - INTVAL (XEXP (src, 1)) * 2);
+	return -(20 - shift * 2);
 
       /* Similarly for HImode and SImode shifts by
 	 small constants on the H8/300H and H8/300S.  */
       if ((TARGET_H8300H || TARGET_H8300S)
-	  && (mode == HImode || mode == SImode)
+	  && (mode == HImode || mode == SImode) && shift <= 4)
-	  && INTVAL (XEXP (src, 1)) <= 4)
+	return -(20 - shift * 2);
-	return -(20 - INTVAL (XEXP (src, 1)) * 2);
 
       /* HImode shifts by small constants for the H8/300.  */
-      if (mode == HImode
+      if (mode == HImode && shift <= 4)
-	  && INTVAL (XEXP (src, 1)) <= 4)
+	return -(20 - (shift * (GET_CODE (src) == ASHIFT ? 2 : 4)));
-	return -(20 - (INTVAL (XEXP (src, 1))
-		       * (GET_CODE (src) == ASHIFT ? 2 : 4)));
 
       /* SImode shifts by small constants for the H8/300.  */
-      if (mode == SImode
+      if (mode == SImode && shift <= 2)
-	  && INTVAL (XEXP (src, 1)) <= 2)
+	return -(20 - (shift * (GET_CODE (src) == ASHIFT ? 6 : 8)));
-	return -(20 - (INTVAL (XEXP (src, 1))
-		       * (GET_CODE (src) == ASHIFT ? 6 : 8)));
 
       /* XXX ??? Could check for more shift/rotate cases here.  */
     }

gcc/config/h8300/h8300.md

@@ -81,6 +81,12 @@
 				     (const_int 6)))]
 	(const_int 200)))
 
+;; The necessity of instruction length adjustment.
+
+(define_attr "adjust_length" "yes,no"
+  (cond [(eq_attr "type" "branch") (const_string "no")]
+        (const_string "yes")))
+
 ;; Condition code settings.
 ;; none - insn does not affect cc
 ;; none_0hit - insn does not affect cc but it does modify operand 0
@@ -983,6 +989,7 @@
    and	%X2,%X0
    bclr	%W2,%R0"
   [(set_attr "length" "2,4")
+   (set_attr "adjust_length" "no")
    (set_attr "cc" "set_znv,none_0hit")])
 
 (define_expand "andqi3"
@@ -1087,6 +1094,7 @@
    or	%X2,%X0
    bset	%V2,%R0"
   [(set_attr "length" "2,4")
+   (set_attr "adjust_length" "no")
    (set_attr "cc" "set_znv,none_0hit")])
 
 (define_expand "iorqi3"
@@ -1173,6 +1181,7 @@
    xor	%X2,%X0
    bnot	%V2,%R0"
   [(set_attr "length" "2,4")
+   (set_attr "adjust_length" "no")
    (set_attr "cc" "set_znv,none_0hit")])
 
 (define_expand "xorqi3"
@@ -2226,7 +2235,8 @@
   ""
   "bld	%Z2,%Y1\;%b4	#0,%R0\;bst	#0,%R0; bl1"
   [(set_attr "cc" "clobber")
-   (set_attr "length" "6")])
+   (set_attr "length" "6")
+   (set_attr "adjust_length" "no")])
 
 (define_insn ""
   [(set (match_operand:HI 0 "bit_operand" "=Ur")
@@ -2240,7 +2250,8 @@
   ""
   "bld	%Z2,%Y1\;%b5	%Z4,%Y3\;bst	#0,%R0; bl3"
   [(set_attr "cc" "clobber")
-   (set_attr "length" "6")])
+   (set_attr "length" "6")
+   (set_attr "adjust_length" "no")])
 
 
 ;; ----------------------------------------------

gcc/final.c

@@ -1318,6 +1318,8 @@ shorten_branches (first)
       /* If needed, do any adjustment.  */
 #ifdef ADJUST_INSN_LENGTH
       ADJUST_INSN_LENGTH (insn, insn_lengths[uid]);
+      if (insn_lengths[uid] < 0)
+	fatal_insn ("Negative insn length", insn);
 #endif
     }