*** empty log message ***

From-SVN: r1023

3 files changed, 19 insertions, 13 deletions

diff --git a/gcc/combine.c b/gcc/combine.c
index 044a413..af6f67d 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -4686,9 +4686,10 @@ apply_distributive_law (x)
     case SUBREG:
       /* Non-paradoxical SUBREGs distributes over all operations, provided
 	 the inner modes and word numbers are the same, this is an extraction
-	 of a low-order part, and we would not be converting a single-word
+	 of a low-order part, we don't convert an fp operation to int or
+	 vice versa, and we would not be converting a single-word
 	 operation into a multi-word operation.  The latter test is not
-	 required, but we prevents generating unneeded multi-word operations.
+	 required, but it prevents generating unneeded multi-word operations.
 	 Some of the previous tests are redundant given the latter test, but
 	 are retained because they are required for correctness.
 
@@ -4697,6 +4698,8 @@ apply_distributive_law (x)
       if (GET_MODE (SUBREG_REG (lhs)) != GET_MODE (SUBREG_REG (rhs))
 	  || SUBREG_WORD (lhs) != SUBREG_WORD (rhs)
 	  || ! subreg_lowpart_p (lhs)
+	  || (GET_MODE_CLASS (GET_MODE (lhs))
+	      != GET_MODE_CLASS (GET_MODE (SUBREG_REG (lhs))))
 	  || (GET_MODE_SIZE (GET_MODE (lhs))
 	      < GET_MODE_SIZE (GET_MODE (SUBREG_REG (lhs))))
 	  || GET_MODE_SIZE (GET_MODE (SUBREG_REG (lhs))) > UNITS_PER_WORD)
diff --git a/gcc/config/i960/i960.md b/gcc/config/i960/i960.md
index 7130a90..d587334 100644
--- a/gcc/config/i960/i960.md
+++ b/gcc/config/i960/i960.md
@@ -1221,6 +1221,11 @@
   "ldos	%1,%0"
   [(set_attr "type" "load")])
 
+;; Using shifts here generates much better code than doing an `and 255'.
+;; This is mainly because the `and' requires loading the constant separately,
+;; the constant is likely to get optimized, and then the compiler can't
+;; optimize the `and' because it doesn't know that one operand is a constant.
+
 (define_expand "zero_extendqisi2"
   [(set (match_operand:SI 0 "register_operand" "")
 	(zero_extend:SI (match_operand:QI 1 "nonimmediate_operand" "")))]
diff --git a/gcc/unroll.c b/gcc/unroll.c
index 8a0b09a..0502eb8 100644
--- a/gcc/unroll.c
+++ b/gcc/unroll.c
@@ -1461,10 +1461,15 @@ copy_loop_body (copy_start, copy_end, map, exit_label, last_iteration,
 	      for (tv = bl->giv; tv; tv = tv->next_iv)
 		if (tv->giv_type == DEST_ADDR && tv->same == v)
 		  {
-		    /* Increment the giv by the amount that was calculated in
-		       find_splittable_givs, and saved in add_val.  */
-		    tv->dest_reg = plus_constant (tv->dest_reg,
-						  INTVAL (tv->add_val));
+		    int this_giv_inc = INTVAL (giv_inc);
+
+		    /* Scale this_giv_inc if the multiplicative factors of
+		       the two givs are different.  */
+		    if (tv->mult_val != v->mult_val)
+		      this_giv_inc = (this_giv_inc / INTVAL (v->mult_val)
+				      * INTVAL (tv->mult_val));
+		       
+		    tv->dest_reg = plus_constant (tv->dest_reg, this_giv_inc);
 		    *tv->location = tv->dest_reg;
 		    
 		    if (last_iteration && unroll_type != UNROLL_COMPLETELY)
@@ -2598,13 +2603,6 @@ find_splittable_givs (bl, unroll_type, loop_start, loop_end, increment,
 		    }
 		}
 
-	      /* Overwrite the old add_val, which is no longer needed, and
-		 substitute the amount that the giv is incremented on each
-		 iteration.  We need to save this somewhere, so we know how
-		 much to increment split DEST_ADDR giv's in copy_loop_body.  */
-
-	      v->add_val = giv_inc;
-
 	      if (loop_dump_stream)
 		fprintf (loop_dump_stream, "DEST_ADDR giv being split.\n");
 	    }