* 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

1 files changed, 26 insertions, 0 deletions

diff --git a/gcc/config/mips/mips.c b/gcc/config/mips/mips.c
index aad3c81..e10c048 100644
--- a/gcc/config/mips/mips.c
+++ b/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);
+}