poly_int: build_ref_for_offset

This patch changes the offset parameter to build_ref_for_offset
from HOST_WIDE_INT to poly_int64.

2017-12-21  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayward  <alan.hayward@arm.com>
	    David Sherwood  <david.sherwood@arm.com>

gcc/
	* ipa-prop.h (build_ref_for_offset): Take the offset as a poly_int64
	rather than a HOST_WIDE_INT.
	* tree-sra.c (build_ref_for_offset): Likewise.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>

From-SVN: r255931

gcc/ChangeLog

@@ -2,6 +2,14 @@
 	    Alan Hayward  <alan.hayward@arm.com>
 	    David Sherwood  <david.sherwood@arm.com>
 
+	* ipa-prop.h (build_ref_for_offset): Take the offset as a poly_int64
+	rather than a HOST_WIDE_INT.
+	* tree-sra.c (build_ref_for_offset): Likewise.
+
+2017-12-21  Richard Sandiford  <richard.sandiford@linaro.org>
+	    Alan Hayward  <alan.hayward@arm.com>
+	    David Sherwood  <david.sherwood@arm.com>
+
 	* fold-const.h (mem_ref_offset): Return a poly_offset_int rather
 	than an offset_int.
 	* tree.c (mem_ref_offset): Likewise.

gcc/ipa-prop.h

@@ -785,7 +785,7 @@ void ipa_release_body_info (struct ipa_func_body_info *);
 tree ipa_get_callee_param_type (struct cgraph_edge *e, int i);
 
 /* From tree-sra.c:  */
-tree build_ref_for_offset (location_t, tree, HOST_WIDE_INT, bool, tree,
+tree build_ref_for_offset (location_t, tree, poly_int64, bool, tree,
 			   gimple_stmt_iterator *, bool);
 
 /* In ipa-cp.c  */

gcc/tree-sra.c

@@ -1706,7 +1706,7 @@ make_fancy_name (tree expr)
    of handling bitfields.  */
 
 tree
-build_ref_for_offset (location_t loc, tree base, HOST_WIDE_INT offset,
+build_ref_for_offset (location_t loc, tree base, poly_int64 offset,
 		      bool reverse, tree exp_type, gimple_stmt_iterator *gsi,
 		      bool insert_after)
 {
@@ -1724,7 +1724,7 @@ build_ref_for_offset (location_t loc, tree base, HOST_WIDE_INT offset,
 				     TYPE_QUALS (exp_type)
 				     | ENCODE_QUAL_ADDR_SPACE (as));
 
-  gcc_checking_assert (offset % BITS_PER_UNIT == 0);
+  poly_int64 byte_offset = exact_div (offset, BITS_PER_UNIT);
   get_object_alignment_1 (base, &align, &misalign);
   base = get_addr_base_and_unit_offset (base, &base_offset);
 
@@ -1746,27 +1746,26 @@ build_ref_for_offset (location_t loc, tree base, HOST_WIDE_INT offset,
       else
 	gsi_insert_before (gsi, stmt, GSI_SAME_STMT);
 
-      off = build_int_cst (reference_alias_ptr_type (prev_base),
-			   offset / BITS_PER_UNIT);
+      off = build_int_cst (reference_alias_ptr_type (prev_base), byte_offset);
       base = tmp;
     }
   else if (TREE_CODE (base) == MEM_REF)
     {
       off = build_int_cst (TREE_TYPE (TREE_OPERAND (base, 1)),
-			   base_offset + offset / BITS_PER_UNIT);
+			   base_offset + byte_offset);
       off = int_const_binop (PLUS_EXPR, TREE_OPERAND (base, 1), off);
       base = unshare_expr (TREE_OPERAND (base, 0));
     }
   else
     {
       off = build_int_cst (reference_alias_ptr_type (prev_base),
-			   base_offset + offset / BITS_PER_UNIT);
+			   base_offset + byte_offset);
       base = build_fold_addr_expr (unshare_expr (base));
     }
 
-  misalign = (misalign + offset) & (align - 1);
-  if (misalign != 0)
-    align = least_bit_hwi (misalign);
+  unsigned int align_bound = known_alignment (misalign + offset);
+  if (align_bound != 0)
+    align = MIN (align, align_bound);
   if (align != TYPE_ALIGN (exp_type))
     exp_type = build_aligned_type (exp_type, align);