* Revamped multiply support for MIPS chips.

        * mips.c (extend_operator): New function.
        (highpart_shift_operator): Likewise.
        * mips.h: Declare new functions.
        (PREDICATE_CODES): Add support for new predicates.
        * mips.md (mulsi3 expander): Simplify.
        (mulsi_mult3): Add another constraint alternative.  Support
        3 operand multiply instructions as found on various mips
        parts.
        (mulsi3_r4650): Delete pattern, now handled by mulsi_mult3.
        (mul_acc_si): New pattern and associated splitters.
        (mulsidi3 expander): Rework to use mulsidi3_64bit and
        mulsidi3_internal.
        (umulsidi3): New expander.
        (mulsidi3_internal): Accept either sign or zero extended
        operands and generate code as appropriate appropriately.
        (mulsidi3_64bit): Similarly.
        (smulsi3_highpart): Turn into an expander and generate code
        to match new patterns.
        (umulsi3_highpart): Likewise.
        (xmulsi3_highpart_internal): New pattern.
        (maddi patterns): Delete.  Replace with:
        (mul_acc_di, mul-acc_64bit_di): New patterns.

Co-Authored-By: Jeffrey A Law <law@cygnus.com>

From-SVN: r20337

gcc/ChangeLog

+Mon Jun  8 16:54:12 1998  Ken Raeburn   <raeburn@cygnus.com>
+                          Jeff Law      <law@cygnus.com>
+
+	* Revamped multiply support for MIPS chips.
+	* mips.c (extend_operator): New function.
+	(highpart_shift_operator): Likewise.
+	* mips.h: Declare new functions.
+	(PREDICATE_CODES): Add support for new predicates.
+	* mips.md (mulsi3 expander): Simplify.
+	(mulsi_mult3): Add another constraint alternative.  Support
+	3 operand multiply instructions as found on various mips
+	parts.
+	(mulsi3_r4650): Delete pattern, now handled by mulsi_mult3.
+	(mul_acc_si): New pattern and associated splitters.
+	(mulsidi3 expander): Rework to use mulsidi3_64bit and
+	mulsidi3_internal.
+	(umulsidi3): New expander.
+	(mulsidi3_internal): Accept either sign or zero extended
+	operands and generate code as appropriate appropriately.
+	(mulsidi3_64bit): Similarly.
+	(smulsi3_highpart): Turn into an expander and generate code
+	to match new patterns.
+	(umulsi3_highpart): Likewise.
+	(xmulsi3_highpart_internal): New pattern.
+	(maddi patterns): Delete.  Replace with:
+	(mul_acc_di, mul-acc_64bit_di): New patterns.
+
 Mon Jun  8 14:16:15 EDT 1998  Andrew MacLeod  <amacleod@cygnus.com>
 
 	* eh-common.h: Remove NEW_EH_MODEL compile time flag, and replace with

gcc/config/mips/mips.c

@@ -8408,3 +8408,29 @@ machine_dependent_reorg (first)
      constants table, we don't need to output the constant in the real
      constant table, but we have no way to prevent that.  */
 }
+
+/* Return nonzero if X is a SIGN or ZERO extend operator.  */
+int
+extend_operator (x, mode)
+     rtx x;
+     enum machine_mode mode;
+{
+  enum rtx_code code = GET_CODE (x);
+  return code == SIGN_EXTEND || code == ZERO_EXTEND;
+}
+
+/* Accept any operator that can be used to shift the high half of the
+   input value to the lower half, suitable for truncation.  The
+   remainder (the lower half of the input, and the upper half of the
+   output) will be discarded.  */
+int
+highpart_shift_operator (x, mode)
+     rtx x;
+     enum machine_mode mode;
+{
+  enum rtx_code code = GET_CODE (x);
+  return (code == LSHIFTRT
+	  || code == ASHIFTRT
+	  || code == ROTATERT
+	  || code == ROTATE);
+}

gcc/config/mips/mips.h

@@ -260,6 +260,8 @@ extern int		se_uns_arith_operand ();
 extern int		se_arith_operand ();
 extern int		se_nonmemory_operand ();
 extern int		se_nonimmediate_operand ();
+extern int              extend_operator ();
+extern int              highpart_shift_operator ();
 extern int		m16_uimm3_b ();
 extern int		m16_simm4_1 ();
 extern int		m16_nsimm4_1 ();
@@ -3641,7 +3643,10 @@ while (0)
 				  REG, SIGN_EXTEND }},			\
   {"se_nonimmediate_operand",   { SUBREG, REG, MEM, SIGN_EXTEND }},	\
   {"consttable_operand",	{ LABEL_REF, SYMBOL_REF, CONST_INT,	\
-				  CONST_DOUBLE, CONST }},
+				  CONST_DOUBLE, CONST }},		\
+  {"extend_operator",           { SIGN_EXTEND, ZERO_EXTEND }},          \
+  {"highpart_shift_operator",   { ASHIFTRT, LSHIFTRT, ROTATERT, ROTATE }},
+
 
 
 /* If defined, a C statement to be executed just prior to the