diff options
Diffstat (limited to 'gcc/alias.c')
| -rw-r--r-- | gcc/alias.c | 44 |
1 files changed, 21 insertions, 23 deletions
diff --git a/gcc/alias.c b/gcc/alias.c index af0141f8cb3..3de48b2973b 100644 --- a/gcc/alias.c +++ b/gcc/alias.c @@ -438,13 +438,18 @@ can_address_p (t) else if (TREE_CODE (t) == BIT_FIELD_REF) return 0; + /* Fields are addressable unless they are marked as nonaddressable or + the containing type has alias set 0. */ else if (TREE_CODE (t) == COMPONENT_REF && ! DECL_NONADDRESSABLE_P (TREE_OPERAND (t, 1)) + && get_alias_set (TREE_TYPE (TREE_OPERAND (t, 0))) != 0 && can_address_p (TREE_OPERAND (t, 0))) return 1; + /* Likewise for arrays. */ else if ((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) && ! TYPE_NONALIASED_COMPONENT (TREE_TYPE (TREE_OPERAND (t, 0))) + && get_alias_set (TREE_TYPE (TREE_OPERAND (t, 0))) != 0 && can_address_p (TREE_OPERAND (t, 0))) return 1; @@ -478,22 +483,25 @@ get_alias_set (t) tree inner = t; tree placeholder_ptr = 0; + /* Remove any nops, then give the language a chance to do + something with this tree before we look at it. */ + STRIP_NOPS (t); + set = (*lang_hooks.get_alias_set) (t); + if (set != -1) + return set; + /* First see if the actual object referenced is an INDIRECT_REF from a - restrict-qualified pointer or a "void *". Start by removing nops - since we care only about the actual object. Also replace + restrict-qualified pointer or a "void *". Replace PLACEHOLDER_EXPRs. */ - while (((TREE_CODE (inner) == NOP_EXPR - || TREE_CODE (inner) == CONVERT_EXPR) - && (TYPE_MODE (TREE_TYPE (inner)) - == TYPE_MODE (TREE_TYPE (TREE_OPERAND (inner, 0))))) - || TREE_CODE (inner) == NON_LVALUE_EXPR - || TREE_CODE (inner) == PLACEHOLDER_EXPR + while (TREE_CODE (inner) == PLACEHOLDER_EXPR || handled_component_p (inner)) { if (TREE_CODE (inner) == PLACEHOLDER_EXPR) inner = find_placeholder (inner, &placeholder_ptr); else inner = TREE_OPERAND (inner, 0); + + STRIP_NOPS (inner); } /* Check for accesses through restrict-qualified pointers. */ @@ -540,27 +548,16 @@ get_alias_set (t) /* Otherwise, pick up the outermost object that we could have a pointer to, processing conversion and PLACEHOLDER_EXPR as above. */ placeholder_ptr = 0; - while (((TREE_CODE (t) == NOP_EXPR || TREE_CODE (t) == CONVERT_EXPR) - && (TYPE_MODE (TREE_TYPE (t)) - == TYPE_MODE (TREE_TYPE (TREE_OPERAND (t, 0))))) - || TREE_CODE (t) == NON_LVALUE_EXPR - || TREE_CODE (t) == PLACEHOLDER_EXPR + while (TREE_CODE (t) == PLACEHOLDER_EXPR || (handled_component_p (t) && ! can_address_p (t))) { - /* Give the language a chance to do something with this tree - before we go inside it. */ - if ((set = lang_get_alias_set (t)) != -1) - return set; - if (TREE_CODE (t) == PLACEHOLDER_EXPR) t = find_placeholder (t, &placeholder_ptr); else t = TREE_OPERAND (t, 0); - } - /* Give the language another chance to do something. */ - if ((set = lang_get_alias_set (t)) != -1) - return set; + STRIP_NOPS (t); + } /* If we've already determined the alias set for a decl, just return it. This is necessary for C++ anonymous unions, whose component @@ -580,7 +577,8 @@ get_alias_set (t) return TYPE_ALIAS_SET (t); /* See if the language has special handling for this type. */ - if ((set = lang_get_alias_set (t)) != -1) + set = (*lang_hooks.get_alias_set) (t); + if (set != -1) return set; /* There are no objects of FUNCTION_TYPE, so there's no point in |