re PR target/26459 (gcc fails to build on powerpc e500-double targets)

	PR target/26459
	* config/rs6000/rs6000.md (DF reg move peephole): Prevent
	peephole removing spe frob_di_df_2.

From-SVN: r112400

gcc/ChangeLog

+2006-03-27  Alan Modra  <amodra@bigpond.net.au>
+
+	PR target/26459
+	* config/rs6000/rs6000.md (DF reg move peephole): Prevent
+	peephole removing spe frob_di_df_2.
+
 2006-03-26  Sebastian Pop  <pop@cri.ensmp.fr>
 
 	* tree-data-ref.c: Rename DDR_SIZE_VECT to DDR_NB_LOOPS.

gcc/config/rs6000/rs6000.md

@@ -9765,18 +9765,20 @@
   "operands[0] = widen_memory_access (operands[0], V2DFmode, 0);
    operands[1] = gen_rtx_REG (V2DFmode, REGNO (operands[1]));")
 
-;; after inserting conditional returns we can sometimes have
+;; After inserting conditional returns we can sometimes have
 ;; unnecessary register moves.  Unfortunately we cannot have a
 ;; modeless peephole here, because some single SImode sets have early
 ;; clobber outputs.  Although those sets expand to multi-ppc-insn
 ;; sequences, using get_attr_length here will smash the operands
 ;; array.  Neither is there an early_cobbler_p predicate.
+;; Disallow subregs for E500 so we don't munge frob_di_df_2.
 (define_peephole2
   [(set (match_operand:DF 0 "gpc_reg_operand" "")
 	(match_operand:DF 1 "any_operand" ""))
    (set (match_operand:DF 2 "gpc_reg_operand" "")
 	(match_dup 0))]
-  "peep2_reg_dead_p (2, operands[0])"
+  "!(TARGET_E500_DOUBLE && GET_CODE (operands[2]) == SUBREG)
+   && peep2_reg_dead_p (2, operands[0])"
   [(set (match_dup 2) (match_dup 1))])
 
 (define_peephole2