Use poly_int tree accessors

This patch generalises various places that used hwi tree accessors so
that they can handle poly_ints instead.  In many cases these changes
are by inspection rather than because something had shown them to be
necessary.

I think the alias.c part is a minor bug fix: previously we used
fits_uhwi_p for a signed HOST_WIDE_INT (which the caller does
treat as signed rather than unsigned).  We also checked whether
each individual offset overflowed but didn't check whether the
sum did.

2018-05-30  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	* alias.c (adjust_offset_for_component_ref): Use poly_int_tree_p
	and wi::to_poly_offset.  Add the current offset and then check
	whether the sum fits, rather than using an unchecked addition of
	a checked term.  Check for a shwi rather than a uhwi.
	* expr.c (get_bit_range): Use tree_to_poly_uint64.
	(store_constructor): Use poly_int_tree_p.
	(expand_expr_real_1): Likewise.
	* function.c (assign_temp): Likewise.
	* fold-const.c (const_binop): Use poly_int_tree_p and
	wi::to_poly_offset.
	(fold_indirect_ref_1): Likewise.  Use multiple_p to attempt an exact
	division.
	* ipa-icf-gimple.c (func_checker::compare_operand): Use
	to_poly_offset for MEM offsets.
	* ipa-icf.c (sem_variable::equals): Likewise.
	* stor-layout.c (compute_record_mode): Use poly_int_tree_p.
	* tree-ssa-sccvn.c (ao_ref_init_from_vn_reference): Use
	wi::to_poly_offset for BIT_FIELD_REF offsets.
	(vn_reference_maybe_forwprop_address): Use poly_int_tree_p and
	wi::to_poly_offset.
	* var-tracking.c (emit_note_insn_var_location): Use
	tree_to_poly_uint64.

From-SVN: r260914

1 files changed, 9 insertions, 8 deletions

diff --git a/gcc/function.c b/gcc/function.c
index 61515e3..6b9fd59 100644
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -978,25 +978,26 @@ assign_temp (tree type_or_decl, int memory_required,
 
   if (mode == BLKmode || memory_required)
     {
-      HOST_WIDE_INT size = int_size_in_bytes (type);
+      poly_int64 size;
       rtx tmp;
 
-      /* Zero sized arrays are GNU C extension.  Set size to 1 to avoid
-	 problems with allocating the stack space.  */
-      if (size == 0)
-	size = 1;
-
       /* Unfortunately, we don't yet know how to allocate variable-sized
 	 temporaries.  However, sometimes we can find a fixed upper limit on
 	 the size, so try that instead.  */
-      else if (size == -1)
+      if (!poly_int_tree_p (TYPE_SIZE_UNIT (type), &size))
 	size = max_int_size_in_bytes (type);
 
+      /* Zero sized arrays are a GNU C extension.  Set size to 1 to avoid
+	 problems with allocating the stack space.  */
+      if (known_eq (size, 0))
+	size = 1;
+
       /* The size of the temporary may be too large to fit into an integer.  */
       /* ??? Not sure this should happen except for user silliness, so limit
 	 this to things that aren't compiler-generated temporaries.  The
 	 rest of the time we'll die in assign_stack_temp_for_type.  */
-      if (decl && size == -1
+      if (decl
+	  && !known_size_p (size)
 	  && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
 	{
 	  error ("size of variable %q+D is too large", decl);