Fwd: Re: Create RECORD_NODE for COMMON blocks contain no EQUIVALENCE objects

[Canqun Yang <canqun at nudt dot edu dot cn>]

Hi, Steven

I attached the new patch. What about this one?

2005-03-25  Canqun Yang  <canqun@nudt.edu.cn>

	* trans-common.c (create_common): Build
RECORD_NODE for common blocks
	contain no equivalence objects.
	(add_equivalences): New argument saw_equiv.
	(translate_common, finish_equivalences): New
local variable saw_equiv.

>
> Looks like a good idea.  A few comments:
>

I also tested the NAS benchmarks on IA-64 1.0GHz.
Three of them make a significant improvements.

              with this patch
bt.W  33.11   22.08 (*)
cg.A  9.17    9.32
ep.W  12.19   12.21
ft.A  38.57   38.80
is.B  33.45   33.14
lu.W  33.75   29.67 (*)
mg.Z  21.43   21.44
sp.W  69.29   58.97 (*)

>
> gfortran prefers tabs over spaces.
>

The other statements in trans-common.c still have
spaces which should be tabs. Another patch to fix
this?


Canqun Yang
Creative Compiler Research Group.
National University of Defense Technology, China.

*** trans-common.c.save	Thu Mar 24 21:30:24 2005
--- trans-common.c	Fri Mar 25 09:45:43 2005
*************** build_common_decl (gfc_common_head *com,
*** 379,385 ****
     backend declarations for all of the elements.  */
  
  static void
! create_common (gfc_common_head *com, segment_info * head)
  {
    segment_info *s, *next_s;
    tree union_type;
--- 379,385 ----
     backend declarations for all of the elements.  */
  
  static void
! create_common (gfc_common_head *com, segment_info * head, bool saw_equiv)
  {
    segment_info *s, *next_s;
    tree union_type;
*************** create_common (gfc_common_head *com, seg
*** 388,395 ****
    tree decl;
    bool is_init = false;
  
!   /* Declare the variables inside the common block.  */
!   union_type = make_node (UNION_TYPE);
    rli = start_record_layout (union_type);
    field_link = &TYPE_FIELDS (union_type);
  
--- 388,403 ----
    tree decl;
    bool is_init = false;
  
!   /* Declare the variables inside the common block.
!      If the current common block contains any equivalence object, then
!      make a UNION_TYPE node, otherwise RECORD_TYPE. This will let the
!      alias analyzer work well when there is no address overlapping for
!      common variables in the current common block.  */
!   if (saw_equiv)
!     union_type = make_node (UNION_TYPE);
!   else
!     union_type = make_node (RECORD_TYPE);
! 
    rli = start_record_layout (union_type);
    field_link = &TYPE_FIELDS (union_type);
  
*************** find_equivalence (segment_info *n)
*** 703,709 ****
     segment list multiple times to include indirect equivalences.  */
  
  static void
! add_equivalences (void)
  {
    segment_info *f;
    bool more;
--- 711,717 ----
     segment list multiple times to include indirect equivalences.  */
  
  static void
! add_equivalences (bool *saw_equiv)
  {
    segment_info *f;
    bool more;
*************** add_equivalences (void)
*** 718,723 ****
--- 726,733 ----
  	    {
  	      f->sym->equiv_built = 1;
  	      more = find_equivalence (f);
+ 	      if (more)
+ 		*saw_equiv = true;
  	    }
  	}
      }
*************** translate_common (gfc_common_head *commo
*** 788,797 ****
--- 798,809 ----
    HOST_WIDE_INT current_offset;
    unsigned HOST_WIDE_INT align;
    unsigned HOST_WIDE_INT max_align;
+   bool saw_equiv;
  
    common_segment = NULL;
    current_offset = 0;
    max_align = 1;
+   saw_equiv = false;
  
    /* Add symbols to the segment.  */
    for (sym = var_list; sym; sym = sym->common_next)
*************** translate_common (gfc_common_head *commo
*** 821,827 ****
  
  	  /* Add all objects directly or indirectly equivalenced with this
  	     symbol.  */
! 	  add_equivalences ();
  
  	  if (current_segment->offset < 0)
  	    gfc_error ("The equivalence set for '%s' cause an invalid "
--- 833,839 ----
  
  	  /* Add all objects directly or indirectly equivalenced with this
  	     symbol.  */
! 	  add_equivalences (&saw_equiv);
  
  	  if (current_segment->offset < 0)
  	    gfc_error ("The equivalence set for '%s' cause an invalid "
*************** translate_common (gfc_common_head *commo
*** 865,871 ****
  		   common->name, &common->where, common_segment->offset);
      }
  
!   create_common (common, common_segment);
  }
  
  
--- 877,883 ----
  		   common->name, &common->where, common_segment->offset);
      }
  
!   create_common (common, common_segment, saw_equiv);
  }
  
  
*************** finish_equivalences (gfc_namespace *ns)
*** 878,884 ****
--- 890,898 ----
    gfc_symbol *sym;
    HOST_WIDE_INT offset;
    unsigned HOST_WIDE_INT align;
+   bool saw_equiv;
  
+   saw_equiv = false;
    for (z = ns->equiv; z; z = z->next)
      for (y = z->eq; y; y = y->eq)
        {
*************** finish_equivalences (gfc_namespace *ns)
*** 888,894 ****
          current_segment = get_segment_info (sym, 0);
  
          /* All objects directly or indirectly equivalenced with this symbol.  */
!         add_equivalences ();
  
  	/* Align the block.  */
  	offset = align_segment (&align);
--- 902,908 ----
          current_segment = get_segment_info (sym, 0);
  
          /* All objects directly or indirectly equivalenced with this symbol.  */
!         add_equivalences (&saw_equiv);
  
  	/* Align the block.  */
  	offset = align_segment (&align);
*************** finish_equivalences (gfc_namespace *ns)
*** 899,905 ****
  	apply_segment_offset (current_segment, offset);
  
  	/* Create the decl.  */
!         create_common (NULL, current_segment);
          break;
        }
  }
--- 913,919 ----
  	apply_segment_offset (current_segment, offset);
  
  	/* Create the decl.  */
!         create_common (NULL, current_segment, saw_equiv);
          break;
        }
  }