[Patch, fortran] [01..06/66] inline sum and product: Prepare gfc_trans_preloop_setup

[Mikael Morin <mikael dot morin at sfr dot fr>]

This is a 6 steps program to update gfc_trans_preloop_setup.
gfc_trans_preloop_setup appeared completely rewritten. These step by step
patches show that it is not the case.
Combined patch attached here.
OK?

diff --git a/trans-array.c b/trans-array.c
index 3472804e4c6344e68d15af2feee627429ca61018..f615e4e6a10d59b6878033876f7b170f516e651b 100644
*** a/trans-array.c
--- b/trans-array.c
*************** gfc_conv_array_ref (gfc_se * se, gfc_arr
*** 2830,2835 ****
--- 2830,2863 ----
  }
  
  
+ /* Add the offset corresponding to array's ARRAY_DIM dimension and loop's
+    LOOP_DIM dimension (if any) to array's offset.  */
+ 
+ static void
+ add_array_offset (stmtblock_t *pblock, gfc_loopinfo *loop, gfc_ss *ss,
+ 		  gfc_array_ref *ar, int array_dim, int loop_dim)
+ {
+   gfc_se se;
+   gfc_ss_info *info;
+   tree stride, index;
+ 
+   info = &ss->data.info;
+ 
+   gfc_init_se (&se, NULL);
+   se.loop = loop;
+   se.expr = info->descriptor;
+   stride = gfc_conv_array_stride (info->descriptor, array_dim);
+   index = gfc_conv_array_index_offset (&se, info, array_dim, loop_dim, ar,
+ 				       stride);
+   gfc_add_block_to_block (pblock, &se.pre);
+ 
+   info->offset = fold_build2_loc (input_location, PLUS_EXPR,
+ 				  gfc_array_index_type,
+ 				  info->offset, index);
+   info->offset = gfc_evaluate_now (info->offset, pblock);
+ }
+ 
+ 
  /* Generate the code to be executed immediately before entering a
     scalarization loop.  */
  
*************** static void
*** 2837,2847 ****
  gfc_trans_preloop_setup (gfc_loopinfo * loop, int dim, int flag,
  			 stmtblock_t * pblock)
  {
-   tree index;
    tree stride;
    gfc_ss_info *info;
    gfc_ss *ss;
!   gfc_se se;
    int i;
  
    /* This code will be executed before entering the scalarization loop
--- 2865,2874 ----
  gfc_trans_preloop_setup (gfc_loopinfo * loop, int dim, int flag,
  			 stmtblock_t * pblock)
  {
    tree stride;
    gfc_ss_info *info;
    gfc_ss *ss;
!   gfc_array_ref *ar;
    int i;
  
    /* This code will be executed before entering the scalarization loop
*************** gfc_trans_preloop_setup (gfc_loopinfo * 
*** 2860,2933 ****
  
        if (dim >= info->dimen)
  	continue;
  
-       if (dim == info->dimen - 1)
- 	{
- 	  /* For the outermost loop calculate the offset due to any
- 	     elemental dimensions.  It will have been initialized with the
- 	     base offset of the array.  */
  	  if (info->ref)
! 	    {
! 	      for (i = 0; i < info->ref->u.ar.dimen; i++)
! 		{
! 		  if (info->ref->u.ar.dimen_type[i] != DIMEN_ELEMENT)
! 		    continue;
  
! 		  gfc_init_se (&se, NULL);
! 		  se.loop = loop;
! 		  se.expr = info->descriptor;
! 		  stride = gfc_conv_array_stride (info->descriptor, i);
! 		  index = gfc_conv_array_index_offset (&se, info, i, -1,
! 						       &info->ref->u.ar,
! 						       stride);
! 		  gfc_add_block_to_block (pblock, &se.pre);
  
! 		  info->offset = fold_build2_loc (input_location, PLUS_EXPR,
! 						  gfc_array_index_type,
! 						  info->offset, index);
! 		  info->offset = gfc_evaluate_now (info->offset, pblock);
! 		}
! 	    }
  
! 	  i = loop->order[0];
! 	  /* For the time being, the innermost loop is unconditionally on
! 	     the first dimension of the scalarization loop.  */
! 	  gcc_assert (i == 0);
  	  stride = gfc_conv_array_stride (info->descriptor, info->dim[i]);
  
  	  /* Calculate the stride of the innermost loop.  Hopefully this will
  	     allow the backend optimizers to do their stuff more effectively.
  	   */
  	  info->stride0 = gfc_evaluate_now (stride, pblock);
- 	}
-       else
- 	{
- 	  /* Add the offset for the previous loop dimension.  */
- 	  gfc_array_ref *ar;
  
  	  if (info->ref)
  	    {
! 	      ar = &info->ref->u.ar;
! 	      i = loop->order[dim + 1];
! 	    }
! 	  else
  	    {
! 	      ar = NULL;
! 	      i = dim + 1;
! 	    }
  
! 	  gfc_init_se (&se, NULL);
! 	  se.loop = loop;
! 	  se.expr = info->descriptor;
! 	  stride = gfc_conv_array_stride (info->descriptor, info->dim[i]);
! 	  index = gfc_conv_array_index_offset (&se, info, info->dim[i], i,
! 					       ar, stride);
! 	  gfc_add_block_to_block (pblock, &se.pre);
! 	  info->offset = fold_build2_loc (input_location, PLUS_EXPR,
! 					  gfc_array_index_type, info->offset,
! 					  index);
! 	  info->offset = gfc_evaluate_now (info->offset, pblock);
  	}
  
        /* Remember this offset for the second loop.  */
        if (dim == loop->temp_dim - 1)
--- 2887,2934 ----
  
        if (dim >= info->dimen)
  	continue;
+       gcc_assert (info->dimen == loop->dimen);
  
        if (info->ref)
! 	ar = &info->ref->u.ar;
!       else
! 	ar = NULL;
  
!       if (dim == loop->dimen - 1)
! 	i = 0;
!       else
! 	i = dim + 1;
  
!       /* For the time being, there is no loop reordering.  */
!       gcc_assert (i == loop->order[i]);
!       i = loop->order[i];
  
!       if (dim == loop->dimen - 1)
! 	{
  	  stride = gfc_conv_array_stride (info->descriptor, info->dim[i]);
  
  	  /* Calculate the stride of the innermost loop.  Hopefully this will
  	     allow the backend optimizers to do their stuff more effectively.
  	   */
  	  info->stride0 = gfc_evaluate_now (stride, pblock);
  
+ 	  /* For the outermost loop calculate the offset due to any
+ 	     elemental dimensions.  It will have been initialized with the
+ 	     base offset of the array.  */
  	  if (info->ref)
  	    {
! 	      for (i = 0; i < ar->dimen; i++)
  		{
! 		  if (ar->dimen_type[i] != DIMEN_ELEMENT)
! 		    continue;
  
! 		  add_array_offset (pblock, loop, ss, ar, i, /* unused */ -1);
  		}
+ 	    }
+ 	}
+       else
+ 	/* Add the offset for the previous loop dimension.  */
+ 	add_array_offset (pblock, loop, ss, ar, info->dim[i], i);
  
        /* Remember this offset for the second loop.  */
        if (dim == loop->temp_dim - 1)