As noticed by Marc.
Bootstrapped / tested on x86_64-unknown-linux-gnu, applied.
Richard.
2019-05-20 Richard Biener <rguent...@suse.de>
* tree-ssa-structalias.c (find_func_aliases): POINTER_MINUS_EXPR
doesn't produce pointers.
{TRUNC,CEIL,FLOOR,ROUND,EXACT}_{DIV,MOD}_EXPR points to what
the first operand points to.
Index: gcc/tree-ssa-structalias.c
===================================================================
--- gcc/tree-ssa-structalias.c (revision 271395)
+++ gcc/tree-ssa-structalias.c (working copy)
@@ -4900,6 +4900,9 @@ find_func_aliases (struct function *fn,
if (code == POINTER_PLUS_EXPR)
get_constraint_for_ptr_offset (gimple_assign_rhs1 (t),
gimple_assign_rhs2 (t), &rhsc);
+ else if (code == POINTER_MINUS_EXPR)
+ /* The result is not a pointer (part). */
+ ;
else if (code == BIT_AND_EXPR
&& TREE_CODE (gimple_assign_rhs2 (t)) == INTEGER_CST)
{
@@ -4908,6 +4911,17 @@ find_func_aliases (struct function *fn,
get_constraint_for_ptr_offset (gimple_assign_rhs1 (t),
NULL_TREE, &rhsc);
}
+ else if (code == TRUNC_DIV_EXPR
+ || code == CEIL_DIV_EXPR
+ || code == FLOOR_DIV_EXPR
+ || code == ROUND_DIV_EXPR
+ || code == EXACT_DIV_EXPR
+ || code == TRUNC_MOD_EXPR
+ || code == CEIL_MOD_EXPR
+ || code == FLOOR_MOD_EXPR
+ || code == ROUND_MID_EXPR)
+ /* Division and modulo transfer the pointer from the LHS. */
+ get_constraint_for_rhs (gimple_assign_rhs1 (t), &rhsc);
else if ((CONVERT_EXPR_CODE_P (code)
&& !(POINTER_TYPE_P (gimple_expr_type (t))
&& !POINTER_TYPE_P (TREE_TYPE (rhsop))))
