[053/nnn] poly_int: decode_addr_const

[Richard Sandiford]

This patch makes the varasm-local addr_const track polynomial offsets.
I'm not sure how useful this is, but it was easier to convert than not.


2017-10-23  Richard Sandiford  <richard.sandif...@linaro.org>
            Alan Hayward  <alan.hayw...@arm.com>
            David Sherwood  <david.sherw...@arm.com>

gcc/
        * varasm.c (addr_const::offset): Change from HOST_WIDE_INT
        to poly_int64.
        (decode_addr_const): Update accordingly.

Index: gcc/varasm.c
===================================================================
--- gcc/varasm.c        2017-10-23 17:11:39.974428235 +0100
+++ gcc/varasm.c        2017-10-23 17:20:52.530629696 +0100
@@ -2873,29 +2873,31 @@ assemble_real (REAL_VALUE_TYPE d, scalar
 
 struct addr_const {
   rtx base;
-  HOST_WIDE_INT offset;
+  poly_int64 offset;
 };
 
 static void
 decode_addr_const (tree exp, struct addr_const *value)
 {
   tree target = TREE_OPERAND (exp, 0);
-  int offset = 0;
+  poly_int64 offset = 0;
   rtx x;
 
   while (1)
     {
+      poly_int64 bytepos;
       if (TREE_CODE (target) == COMPONENT_REF
-         && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
+         && poly_int_tree_p (byte_position (TREE_OPERAND (target, 1)),
+                             &bytepos))
        {
-         offset += int_byte_position (TREE_OPERAND (target, 1));
+         offset += bytepos;
          target = TREE_OPERAND (target, 0);
        }
       else if (TREE_CODE (target) == ARRAY_REF
               || TREE_CODE (target) == ARRAY_RANGE_REF)
        {
          offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
-                    * tree_to_shwi (TREE_OPERAND (target, 1)));
+                    * tree_to_poly_int64 (TREE_OPERAND (target, 1)));
          target = TREE_OPERAND (target, 0);
        }
       else if (TREE_CODE (target) == MEM_REF
@@ -3042,14 +3044,14 @@ const_hash_1 (const tree exp)
          case SYMBOL_REF:
            /* Don't hash the address of the SYMBOL_REF;
               only use the offset and the symbol name.  */
-           hi = value.offset;
+           hi = value.offset.coeffs[0];
            p = XSTR (value.base, 0);
            for (i = 0; p[i] != 0; i++)
              hi = ((hi * 613) + (unsigned) (p[i]));
            break;
 
          case LABEL_REF:
-           hi = (value.offset
+           hi = (value.offset.coeffs[0]
                  + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
            break;
 
@@ -3242,7 +3244,7 @@ compare_constant (const tree t1, const t
        decode_addr_const (t1, &value1);
        decode_addr_const (t2, &value2);
 
-       if (value1.offset != value2.offset)
+       if (may_ne (value1.offset, value2.offset))
          return 0;
 
        code = GET_CODE (value1.base);