rx: Cleanup flags generation.

All arithmetic should only clobber the flags by default;
setting the flags to a useful value should be done by a
separate pattern.

From-SVN: r168924

gcc/ChangeLog

 2011-01-17  Richard Henderson  <rth@redhat.com>
 
+	* config/rx/rx.c (rx_match_ccmode): New.
+	* config/rx/rx-protos.h: Update.
+	* config/rx/rx.md (abssi2): Clobber, don't set flags.
+	(addsi3, adddi3, andsi3, negsi2, one_cmplsi2, iorsi3): Likewise.
+	(rotlsi3, rotrsi3, ashrsi3, lshrsi3, ashlsi3): Likewise.
+	(subsi3, subdi3, xorsi3, addsf3, divsf3, mulsf3, subsf3): Likewise.
+	(fix_truncsfsi2, floatsisf2): Likewise.
+	(*abssi2_flags, *addsi3_flags, *andsi3_flags, *negsi2_flags): New.
+	(*one_cmplsi2_flags, *iorsi3_flags, *rotlsi3_flags): New.
+	(*rotrsi3_flags, *ashrsi3_flags, *lshrsi3_flags, *ashlsi3_flags): New.
+	(*subsi3_flags, *xorsi3_flags): New.
+
 	* config/rx/rx.md (cstoresf4, *cstoresf4): New patterns.
 
 	* config/rx/rx.c (rx_print_operand): Remove workaround for

gcc/config/rx/rx-protos.h

@@ -42,6 +42,7 @@ extern void		rx_notice_update_cc (rtx body, rtx insn);
 extern void		rx_split_cbranch (Mmode, Rcode, rtx, rtx, rtx);
 extern bool		rx_split_fp_compare (Rcode, Rcode *, Rcode *);
 extern Mmode		rx_select_cc_mode (Rcode, rtx, rtx);
+extern bool		rx_match_ccmode (rtx, Mmode);
 #endif
 
 #endif /* GCC_RX_PROTOS_H */

gcc/config/rx/rx.c

@@ -2755,6 +2755,34 @@ rx_split_cbranch (enum machine_mode cc_mode, enum rtx_code cmp1,
   emit_jump_insn (x);
 }
 
+/* A helper function for matching parallels that set the flags.  */
+
+bool
+rx_match_ccmode (rtx insn, enum machine_mode cc_mode)
+{
+  rtx op1, flags;
+  enum machine_mode flags_mode;
+
+  gcc_checking_assert (XVECLEN (PATTERN (insn), 0) == 2);
+
+  op1 = XVECEXP (PATTERN (insn), 0, 1);
+  gcc_checking_assert (GET_CODE (SET_SRC (op1)) == COMPARE);
+
+  flags = SET_DEST (op1);
+  flags_mode = GET_MODE (flags);
+
+  if (GET_MODE (SET_SRC (op1)) != flags_mode)
+    return false;
+  if (GET_MODE_CLASS (flags_mode) != MODE_CC)
+    return false;
+
+  /* Ensure that the mode of FLAGS is compatible with CC_MODE.  */
+  if (flags_from_mode (flags_mode) & ~flags_from_mode (cc_mode))
+    return false;
+
+  return true;
+}
+
 
 #undef  TARGET_FUNCTION_VALUE
 #define TARGET_FUNCTION_VALUE		rx_function_value