/* C-family attributes handling.
- Copyright (C) 1992-2018 Free Software Foundation, Inc.
+ Copyright (C) 1992-2019 Free Software Foundation, Inc.
This file is part of GCC.
#include "tree-iterator.h"
#include "opts.h"
#include "gimplify.h"
+#include "tree-pretty-print.h"
static tree handle_packed_attribute (tree *, tree, tree, int, bool *);
static tree handle_nocommon_attribute (tree *, tree, tree, int, bool *);
static tree handle_fallthrough_attribute (tree *, tree, tree, int, bool *);
static tree handle_patchable_function_entry_attribute (tree *, tree, tree,
int, bool *);
+static tree handle_copy_attribute (tree *, tree, tree, int, bool *);
/* Helper to define attribute exclusions. */
#define ATTR_EXCL(name, function, type, variable) \
ATTR_EXCL (NULL, false, false, false)
};
-static const struct attribute_spec::exclusions attr_cold_hot_exclusions[] =
+extern const struct attribute_spec::exclusions attr_cold_hot_exclusions[] =
{
ATTR_EXCL ("cold", true, true, true),
ATTR_EXCL ("hot", true, true, true),
handle_omp_declare_target_attribute, NULL },
{ "omp declare target link", 0, 0, true, false, false, false,
handle_omp_declare_target_attribute, NULL },
+ { "omp declare target implicit", 0, 0, true, false, false, false,
+ handle_omp_declare_target_attribute, NULL },
{ "alloc_align", 1, 1, false, true, true, false,
handle_alloc_align_attribute,
attr_alloc_exclusions },
NULL },
{ "nocf_check", 0, 0, false, true, true, true,
handle_nocf_check_attribute, NULL },
+ { "copy", 1, 1, false, false, false, false,
+ handle_copy_attribute, NULL },
{ NULL, 0, 0, false, false, false, false, NULL, NULL }
};
return targetm.attribute_takes_identifier_p (attr_id);
}
+/* Verify that argument value POS at position ARGNO to attribute NAME
+ applied to function TYPE refers to a function parameter at position
+ POS and the expected type CODE. Treat CODE == INTEGER_TYPE as
+ matching all C integral types except bool. If successful, return
+ POS after default conversions, if any. Otherwise, issue appropriate
+ warnings and return null. A non-zero 1-based ARGNO should be passed
+ in by callers only for attributes with more than one argument. */
+
+tree
+positional_argument (const_tree fntype, const_tree atname, tree pos,
+ tree_code code, int argno /* = 0 */,
+ int flags /* = posargflags () */)
+{
+ if (pos && TREE_CODE (pos) != IDENTIFIER_NODE
+ && TREE_CODE (pos) != FUNCTION_DECL)
+ pos = default_conversion (pos);
+
+ tree postype = TREE_TYPE (pos);
+ if (pos == error_mark_node || !postype)
+ {
+ /* Only mention the positional argument number when it's non-zero. */
+ if (argno < 1)
+ warning (OPT_Wattributes,
+ "%qE attribute argument is invalid", atname);
+ else
+ warning (OPT_Wattributes,
+ "%qE attribute argument %i is invalid", atname, argno);
+
+ return NULL_TREE;
+ }
+
+ if (!INTEGRAL_TYPE_P (postype))
+ {
+ /* Handle this case specially to avoid mentioning the value
+ of pointer constants in diagnostics. Only mention
+ the positional argument number when it's non-zero. */
+ if (argno < 1)
+ warning (OPT_Wattributes,
+ "%qE attribute argument has type %qT",
+ atname, postype);
+ else
+ warning (OPT_Wattributes,
+ "%qE attribute argument %i has type %qT",
+ atname, argno, postype);
+
+ return NULL_TREE;
+ }
+
+ if (TREE_CODE (pos) != INTEGER_CST)
+ {
+ /* Only mention the argument number when it's non-zero. */
+ if (argno < 1)
+ warning (OPT_Wattributes,
+ "%qE attribute argument value %qE is not an integer "
+ "constant",
+ atname, pos);
+ else
+ warning (OPT_Wattributes,
+ "%qE attribute argument %i value %qE is not an integer "
+ "constant",
+ atname, argno, pos);
+
+ return NULL_TREE;
+ }
+
+ /* Argument positions are 1-based. */
+ if (integer_zerop (pos))
+ {
+ if (flags & POSARG_ZERO)
+ /* Zero is explicitly allowed. */
+ return pos;
+
+ if (argno < 1)
+ warning (OPT_Wattributes,
+ "%qE attribute argument value %qE does not refer to "
+ "a function parameter",
+ atname, pos);
+ else
+ warning (OPT_Wattributes,
+ "%qE attribute argument %i value %qE does not refer to "
+ "a function parameter",
+ atname, argno, pos);
+
+ return NULL_TREE;
+ }
+
+ if (!prototype_p (fntype))
+ return pos;
+
+ /* Verify that the argument position does not exceed the number
+ of formal arguments to the function. When POSARG_ELLIPSIS
+ is set, ARGNO may be beyond the last argument of a vararg
+ function. */
+ unsigned nargs = type_num_arguments (fntype);
+ if (!nargs
+ || !tree_fits_uhwi_p (pos)
+ || ((flags & POSARG_ELLIPSIS) == 0
+ && !IN_RANGE (tree_to_uhwi (pos), 1, nargs)))
+ {
+
+ if (argno < 1)
+ warning (OPT_Wattributes,
+ "%qE attribute argument value %qE exceeds the number "
+ "of function parameters %u",
+ atname, pos, nargs);
+ else
+ warning (OPT_Wattributes,
+ "%qE attribute argument %i value %qE exceeds the number "
+ "of function parameters %u",
+ atname, argno, pos, nargs);
+ return NULL_TREE;
+ }
+
+ /* Verify that the type of the referenced formal argument matches
+ the expected type. */
+ unsigned HOST_WIDE_INT ipos = tree_to_uhwi (pos);
+
+ /* Zero was handled above. */
+ gcc_assert (ipos != 0);
+
+ if (tree argtype = type_argument_type (fntype, ipos))
+ {
+ if (flags & POSARG_ELLIPSIS)
+ {
+ if (argno < 1)
+ error ("%qE attribute argument value %qE does not refer to "
+ "a variable argument list",
+ atname, pos);
+ else
+ error ("%qE attribute argument %i value %qE does not refer to "
+ "a variable argument list",
+ atname, argno, pos);
+ return NULL_TREE;
+ }
+
+ /* Where the expected code is STRING_CST accept any pointer
+ expected by attribute format (this includes possibly qualified
+ char pointers and, for targets like Darwin, also pointers to
+ struct CFString). */
+ bool type_match;
+ if (code == STRING_CST)
+ type_match = valid_format_string_type_p (argtype);
+ else if (code == INTEGER_TYPE)
+ /* For integers, accept enums, wide characters and other types
+ that match INTEGRAL_TYPE_P except for bool. */
+ type_match = (INTEGRAL_TYPE_P (argtype)
+ && TREE_CODE (argtype) != BOOLEAN_TYPE);
+ else
+ type_match = TREE_CODE (argtype) == code;
+
+ if (!type_match)
+ {
+ if (code == STRING_CST)
+ {
+ /* Reject invalid format strings with an error. */
+ if (argno < 1)
+ error ("%qE attribute argument value %qE refers to "
+ "parameter type %qT",
+ atname, pos, argtype);
+ else
+ error ("%qE attribute argument %i value %qE refers to "
+ "parameter type %qT",
+ atname, argno, pos, argtype);
+
+ return NULL_TREE;
+ }
+
+ if (argno < 1)
+ warning (OPT_Wattributes,
+ "%qE attribute argument value %qE refers to "
+ "parameter type %qT",
+ atname, pos, argtype);
+ else
+ warning (OPT_Wattributes,
+ "%qE attribute argument %i value %qE refers to "
+ "parameter type %qT",
+ atname, argno, pos, argtype);
+ return NULL_TREE;
+ }
+ }
+ else if (!(flags & POSARG_ELLIPSIS))
+ {
+ if (argno < 1)
+ warning (OPT_Wattributes,
+ "%qE attribute argument value %qE refers to "
+ "a variadic function parameter of unknown type",
+ atname, pos);
+ else
+ warning (OPT_Wattributes,
+ "%qE attribute argument %i value %qE refers to "
+ "a variadic function parameter of unknown type",
+ atname, argno, pos);
+ return NULL_TREE;
+ }
+
+ return pos;
+}
+
+
/* Attribute handlers common to C front ends. */
/* Handle a "packed" attribute; arguments as in
if (TYPE_P (*node))
{
if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
- *node = build_variant_type_copy (*node);
- TYPE_PACKED (*node) = 1;
+ {
+ warning (OPT_Wattributes,
+ "%qE attribute ignored for type %qT", name, *node);
+ *no_add_attrs = true;
+ }
+ else
+ TYPE_PACKED (*node) = 1;
}
else if (TREE_CODE (*node) == FIELD_DECL)
{
else if (!(flag_cf_protection & CF_BRANCH))
{
warning (OPT_Wattributes, "%qE attribute ignored. Use "
- "-fcf-protection option to enable it", name);
+ "%<-fcf-protection%> option to enable it",
+ name);
*no_add_attrs = true;
}
if (pri <= MAX_RESERVED_INIT_PRIORITY)
{
if (is_destructor)
- warning (0,
+ warning (OPT_Wprio_ctor_dtor,
"destructor priorities from 0 to %d are reserved "
"for the implementation",
MAX_RESERVED_INIT_PRIORITY);
else
- warning (0,
+ warning (OPT_Wprio_ctor_dtor,
"constructor priorities from 0 to %d are reserved "
"for the implementation",
MAX_RESERVED_INIT_PRIORITY);
else if (TYPE_P (*node))
type = node, is_type = true;
+ /* True to consider invalid alignments greater than MAX_OFILE_ALIGNMENT. */
+ bool objfile = (TREE_CODE (*node) == FUNCTION_DECL
+ || (VAR_P (*node) && TREE_STATIC (*node)));
/* Log2 of specified alignment. */
- int pow2align = check_user_alignment (align_expr, true);
+ int pow2align = check_user_alignment (align_expr, objfile,
+ /* warn_zero = */ true);
if (pow2align == -1
|| !check_cxx_fundamental_alignment_constraints (*node, pow2align, flags))
{
unsigned curalign = 0;
unsigned lastalign = 0;
+ /* True when SET_DECL_ALIGN() should be called for the decl when
+ *NO_ADD_ATTRS is false. */
+ bool set_align = true;
if (is_type)
{
if ((flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
curalign = lastalign;
curalign /= BITS_PER_UNIT;
- bitalign /= BITS_PER_UNIT;
-
- bool diagd = true;
- if (DECL_USER_ALIGN (decl) || DECL_USER_ALIGN (last_decl))
- diagd = warning (OPT_Wattributes,
- "ignoring attribute %<%E (%u)%> because it conflicts "
- "with attribute %<%E (%u)%>",
- name, bitalign, name, curalign);
- else if (!warn_if_not_aligned_p)
- /* Do not error out for attribute warn_if_not_aligned. */
- error ("alignment for %q+D must be at least %d", decl, curalign);
+ unsigned newalign = bitalign / BITS_PER_UNIT;
- if (diagd && note)
- inform (DECL_SOURCE_LOCATION (last_decl), "previous declaration here");
-
- *no_add_attrs = true;
+ auto_diagnostic_group d;
+ if ((DECL_USER_ALIGN (decl)
+ || DECL_USER_ALIGN (last_decl)))
+ {
+ if (warning (OPT_Wattributes,
+ "ignoring attribute %<%E (%u)%> because it conflicts "
+ "with attribute %<%E (%u)%>",
+ name, newalign, name, curalign)
+ && note)
+ inform (DECL_SOURCE_LOCATION (last_decl),
+ "previous declaration here");
+ /* Only reject attempts to relax/override an alignment
+ explicitly specified previously and accept declarations
+ that appear to relax the implicit function alignment for
+ the target. Both increasing and increasing the alignment
+ set by -falign-functions setting is permitted. */
+ *no_add_attrs = true;
+ }
+ else if (!warn_if_not_aligned_p)
+ {
+ /* Do not fail for attribute warn_if_not_aligned. Otherwise,
+ silently avoid applying the alignment to the declaration
+ because it's implicitly satisfied by the target. Apply
+ the attribute nevertheless so it can be retrieved by
+ __builtin_has_attribute. */
+ set_align = false;
+ }
}
else if (DECL_USER_ALIGN (decl)
&& DECL_ALIGN (decl) > bitalign)
&& TREE_CODE (decl) == FUNCTION_DECL
&& DECL_ALIGN (decl) > bitalign)
{
- /* Don't warn function alignment here if warn_if_not_aligned_p is
- true. It will be warned later. */
+ /* Don't warn for function alignment here if warn_if_not_aligned_p
+ is true. It will be warned about later. */
if (DECL_USER_ALIGN (decl))
- error ("alignment for %q+D was previously specified as %d "
- "and may not be decreased", decl,
- DECL_ALIGN (decl) / BITS_PER_UNIT);
- else
- error ("alignment for %q+D must be at least %d", decl,
- DECL_ALIGN (decl) / BITS_PER_UNIT);
- *no_add_attrs = true;
- }
- else
- {
- if (warn_if_not_aligned_p)
{
- if (TREE_CODE (decl) == FIELD_DECL && !DECL_C_BIT_FIELD (decl))
- {
- SET_DECL_WARN_IF_NOT_ALIGN (decl, bitalign);
- warn_if_not_aligned_p = false;
- }
- }
- else
- {
- SET_DECL_ALIGN (decl, bitalign);
- DECL_USER_ALIGN (decl) = 1;
+ /* Only reject attempts to relax/override an alignment
+ explicitly specified previously and accept declarations
+ that appear to relax the implicit function alignment for
+ the target. Both increasing and increasing the alignment
+ set by -falign-functions setting is permitted. */
+ error ("alignment for %q+D was previously specified as %d "
+ "and may not be decreased", decl,
+ DECL_ALIGN (decl) / BITS_PER_UNIT);
+ *no_add_attrs = true;
}
}
+ else if (warn_if_not_aligned_p
+ && TREE_CODE (decl) == FIELD_DECL
+ && !DECL_C_BIT_FIELD (decl))
+ {
+ SET_DECL_WARN_IF_NOT_ALIGN (decl, bitalign);
+ warn_if_not_aligned_p = false;
+ set_align = false;
+ }
if (warn_if_not_aligned_p)
{
decl);
*no_add_attrs = true;
}
+ else if (!is_type && !*no_add_attrs && set_align)
+ {
+ SET_DECL_ALIGN (decl, bitalign);
+ DECL_USER_ALIGN (decl) = 1;
+ }
return NULL_TREE;
}
return handle_alias_ifunc_attribute (true, node, name, args, no_add_attrs);
}
+/* Handle the "copy" attribute NAME by copying the set of attributes
+ from the symbol referenced by ARGS to the declaration of *NODE. */
+
+static tree
+handle_copy_attribute (tree *node, tree name, tree args,
+ int flags, bool *no_add_attrs)
+{
+ /* Do not apply the copy attribute itself. It serves no purpose
+ other than to copy other attributes. */
+ *no_add_attrs = true;
+
+ tree decl = *node;
+
+ tree ref = TREE_VALUE (args);
+ if (ref == error_mark_node)
+ return NULL_TREE;
+
+ if (TREE_CODE (ref) == STRING_CST)
+ {
+ /* Explicitly handle this case since using a string literal
+ as an argument is a likely mistake. */
+ error_at (DECL_SOURCE_LOCATION (decl),
+ "%qE attribute argument cannot be a string",
+ name);
+ return NULL_TREE;
+ }
+
+ if (CONSTANT_CLASS_P (ref)
+ && (INTEGRAL_TYPE_P (TREE_TYPE (ref))
+ || FLOAT_TYPE_P (TREE_TYPE (ref))))
+ {
+ /* Similar to the string case, since some function attributes
+ accept literal numbers as arguments (e.g., alloc_size or
+ nonnull) using one here is a likely mistake. */
+ error_at (DECL_SOURCE_LOCATION (decl),
+ "%qE attribute argument cannot be a constant arithmetic "
+ "expression",
+ name);
+ return NULL_TREE;
+ }
+
+ if (ref == node[1])
+ {
+ /* Another possible mistake (but indirect self-references aren't
+ and diagnosed and shouldn't be). */
+ if (warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wattributes,
+ "%qE attribute ignored on a redeclaration "
+ "of the referenced symbol",
+ name))
+ inform (DECL_SOURCE_LOCATION (node[1]),
+ "previous declaration here");
+ return NULL_TREE;
+ }
+
+ /* Consider address-of expressions in the attribute argument
+ as requests to copy from the referenced entity. For constant
+ expressions, consider those to be requests to copy from their
+ type, such as in:
+ struct __attribute__ (copy ((struct T *)0)) U { ... };
+ which copies type attributes from struct T to the declaration
+ of struct U. */
+ if (TREE_CODE (ref) == ADDR_EXPR)
+ ref = TREE_OPERAND (ref, 0);
+ else if (CONSTANT_CLASS_P (ref))
+ ref = TREE_TYPE (ref);
+
+ if (DECL_P (decl))
+ {
+ if ((VAR_P (decl)
+ && (TREE_CODE (ref) == FUNCTION_DECL
+ || (EXPR_P (ref)
+ && POINTER_TYPE_P (TREE_TYPE (ref))
+ && FUNC_OR_METHOD_TYPE_P (TREE_TYPE (TREE_TYPE (ref))))))
+ || (TREE_CODE (decl) == FUNCTION_DECL
+ && (VAR_P (ref)
+ || (EXPR_P (ref)
+ && !FUNC_OR_METHOD_TYPE_P (TREE_TYPE (ref))))))
+ {
+ /* It makes no sense to try to copy function attributes
+ to a variable, or variable attributes to a function. */
+ if (warning (OPT_Wattributes,
+ "%qE attribute ignored on a declaration of "
+ "a different kind than referenced symbol",
+ name)
+ && DECL_P (ref))
+ inform (DECL_SOURCE_LOCATION (ref),
+ "symbol %qD referenced by %qD declared here", ref, decl);
+ return NULL_TREE;
+ }
+
+ tree attrs = NULL_TREE;
+ if (DECL_P (ref))
+ attrs = DECL_ATTRIBUTES (ref);
+ else if (TYPE_P (ref))
+ attrs = TYPE_ATTRIBUTES (ref);
+
+ /* Copy decl attributes from REF to DECL. */
+ for (tree at = attrs; at; at = TREE_CHAIN (at))
+ {
+ /* Avoid copying attributes that affect a symbol linkage,
+ inlining, or visibility since those in all likelihood
+ only apply to the target.
+ FIXME: make it possible to specify which attributes to
+ copy or not to copy in the copy attribute itself. */
+ tree atname = get_attribute_name (at);
+ if (is_attribute_p ("alias", atname)
+ || is_attribute_p ("always_inline", atname)
+ || is_attribute_p ("gnu_inline", atname)
+ || is_attribute_p ("ifunc", atname)
+ || is_attribute_p ("noinline", atname)
+ || is_attribute_p ("visibility", atname)
+ || is_attribute_p ("weak", atname)
+ || is_attribute_p ("weakref", atname))
+ continue;
+
+ /* Attribute leaf only applies to extern functions.
+ Avoid copying it to static ones. */
+ if (!TREE_PUBLIC (decl)
+ && is_attribute_p ("leaf", atname))
+ continue;
+
+ tree atargs = TREE_VALUE (at);
+ /* Create a copy of just the one attribute ar AT, including
+ its argumentsm and add it to DECL. */
+ tree attr = tree_cons (atname, copy_list (atargs), NULL_TREE);
+ decl_attributes (node, attr, flags, ref);
+ }
+
+ /* Proceed to copy type attributes below. */
+ }
+ else if (!TYPE_P (decl))
+ {
+ error_at (DECL_SOURCE_LOCATION (decl),
+ "%qE attribute must apply to a declaration",
+ name);
+ return NULL_TREE;
+ }
+
+ /* A function declared with attribute nothrow has the attribute
+ attached to it, but a C++ throw() function does not. */
+ if (TREE_NOTHROW (ref))
+ TREE_NOTHROW (decl) = true;
+
+ /* Similarly, a function declared with attribute noreturn has it
+ attached on to it, but a C11 _Noreturn function does not. */
+ tree reftype = ref;
+ if (DECL_P (ref)
+ && TREE_THIS_VOLATILE (ref)
+ && FUNC_OR_METHOD_TYPE_P (TREE_TYPE (reftype)))
+ TREE_THIS_VOLATILE (decl) = true;
+
+ if (DECL_P (ref) || EXPR_P (ref))
+ reftype = TREE_TYPE (ref);
+
+ if (POINTER_TYPE_P (reftype))
+ reftype = TREE_TYPE (reftype);
+
+ if (!TYPE_P (reftype))
+ return NULL_TREE;
+
+ tree attrs = TYPE_ATTRIBUTES (reftype);
+
+ /* Copy type attributes from REF to DECL. */
+ for (tree at = attrs; at; at = TREE_CHAIN (at))
+ decl_attributes (node, at, flags, ref);
+
+ return NULL_TREE;
+}
+
/* Handle a "weakref" attribute; arguments as in struct
attribute_spec.handler. */
tree decl = *node;
enum tls_model kind;
- if (!VAR_P (decl) || !DECL_THREAD_LOCAL_P (decl))
+ if (!VAR_P (decl))
{
- warning (OPT_Wattributes, "%qE attribute ignored", name);
+ warning (OPT_Wattributes, "%qE attribute ignored because %qD "
+ "is not a variable",
+ name, decl);
+ return NULL_TREE;
+ }
+
+ if (!DECL_THREAD_LOCAL_P (decl))
+ {
+ warning (OPT_Wattributes, "%qE attribute ignored because %qD does "
+ "not have thread storage duration", name, decl);
return NULL_TREE;
}
id = TREE_VALUE (args);
if (TREE_CODE (id) != STRING_CST)
{
- error ("tls_model argument not a string");
+ error ("%qE argument not a string", name);
return NULL_TREE;
}
else if (!strcmp (TREE_STRING_POINTER (id), "global-dynamic"))
kind = TLS_MODEL_GLOBAL_DYNAMIC;
else
- error ("tls_model argument must be one of \"local-exec\", \"initial-exec\", \"local-dynamic\" or \"global-dynamic\"");
+ error ("%qE argument must be one of %qs, %qs, %qs, or %qs",
+ name,
+ "local-exec", "initial-exec", "local-dynamic", "global-dynamic");
set_decl_tls_model (decl, kind);
return NULL_TREE;
struct attribute_spec.handler. */
static tree
-handle_alloc_size_attribute (tree *node, tree ARG_UNUSED (name), tree args,
+handle_alloc_size_attribute (tree *node, tree name, tree args,
int ARG_UNUSED (flags), bool *no_add_attrs)
{
- unsigned arg_count = type_num_arguments (*node);
- for (; args; args = TREE_CHAIN (args))
+ tree decl = *node;
+ tree rettype = TREE_TYPE (decl);
+ if (!POINTER_TYPE_P (rettype))
{
- tree position = TREE_VALUE (args);
- if (position && TREE_CODE (position) != IDENTIFIER_NODE
- && TREE_CODE (position) != FUNCTION_DECL)
- position = default_conversion (position);
+ warning (OPT_Wattributes,
+ "%qE attribute ignored on a function returning %qT",
+ name, rettype);
+ *no_add_attrs = true;
+ return NULL_TREE;
+ }
- if (!tree_fits_uhwi_p (position)
- || !arg_count
- || !IN_RANGE (tree_to_uhwi (position), 1, arg_count))
+ for (int i = 1; args; ++i)
+ {
+ tree pos = TREE_VALUE (args);
+ /* NEXT is null when the attribute includes just one argument.
+ That's used to tell positional_argument to avoid mentioning
+ the argument number in diagnostics (since there's just one
+ mentioning it is unnecessary and coule be confusing). */
+ tree next = TREE_CHAIN (args);
+ if (tree val = positional_argument (decl, name, pos, INTEGER_TYPE,
+ next || i > 1 ? i : 0))
+ TREE_VALUE (args) = val;
+ else
{
- warning (OPT_Wattributes,
- "alloc_size parameter outside range");
*no_add_attrs = true;
- return NULL_TREE;
+ break;
}
+
+ args = next;
}
+
return NULL_TREE;
}
struct attribute_spec.handler. */
static tree
-handle_alloc_align_attribute (tree *node, tree, tree args, int,
+handle_alloc_align_attribute (tree *node, tree name, tree args, int,
bool *no_add_attrs)
{
- unsigned arg_count = type_num_arguments (*node);
- tree position = TREE_VALUE (args);
- if (position && TREE_CODE (position) != IDENTIFIER_NODE
- && TREE_CODE (position) != FUNCTION_DECL)
- position = default_conversion (position);
-
- if (!tree_fits_uhwi_p (position)
- || !arg_count
- || !IN_RANGE (tree_to_uhwi (position), 1, arg_count))
+ tree decl = *node;
+ tree rettype = TREE_TYPE (decl);
+ if (!POINTER_TYPE_P (rettype))
{
warning (OPT_Wattributes,
- "alloc_align parameter outside range");
+ "%qE attribute ignored on a function returning %qT",
+ name, rettype);
*no_add_attrs = true;
return NULL_TREE;
}
+
+ if (!positional_argument (*node, name, TREE_VALUE (args), INTEGER_TYPE))
+ *no_add_attrs = true;
+
return NULL_TREE;
}
struct attribute_spec.handler. */
static tree
-handle_assume_aligned_attribute (tree *, tree, tree args, int,
+handle_assume_aligned_attribute (tree *node, tree name, tree args, int,
bool *no_add_attrs)
{
+ tree decl = *node;
+ tree rettype = TREE_TYPE (decl);
+ if (TREE_CODE (rettype) != POINTER_TYPE)
+ {
+ warning (OPT_Wattributes,
+ "%qE attribute ignored on a function returning %qT",
+ name, rettype);
+ *no_add_attrs = true;
+ return NULL_TREE;
+ }
+
+ /* The alignment specified by the first argument. */
+ tree align = NULL_TREE;
+
for (; args; args = TREE_CHAIN (args))
{
- tree position = TREE_VALUE (args);
- if (position && TREE_CODE (position) != IDENTIFIER_NODE
- && TREE_CODE (position) != FUNCTION_DECL)
- position = default_conversion (position);
+ tree val = TREE_VALUE (args);
+ if (val && TREE_CODE (val) != IDENTIFIER_NODE
+ && TREE_CODE (val) != FUNCTION_DECL)
+ val = default_conversion (val);
+
+ if (!tree_fits_shwi_p (val))
+ {
+ warning (OPT_Wattributes,
+ "%qE attribute %E is not an integer constant",
+ name, val);
+ *no_add_attrs = true;
+ return NULL_TREE;
+ }
+
+ if (!align)
+ {
+ /* Validate and save the alignment. */
+ if (!integer_pow2p (val))
+ {
+ warning (OPT_Wattributes,
+ "%qE attribute argument %E is not a power of 2",
+ name, val);
+ *no_add_attrs = true;
+ return NULL_TREE;
+ }
- if (TREE_CODE (position) != INTEGER_CST)
+ align = val;
+ }
+ else if (tree_int_cst_sgn (val) < 0 || tree_int_cst_le (align, val))
{
+ /* The misalignment specified by the second argument
+ must be non-negative and less than the alignment. */
warning (OPT_Wattributes,
- "assume_aligned parameter not integer constant");
+ "%qE attribute argument %E is not in the range [0, %E)",
+ name, val, align);
*no_add_attrs = true;
return NULL_TREE;
}
return NULL_TREE;
}
-/* Handle a "vector_size" attribute; arguments as in
- struct attribute_spec.handler. */
-
+/* Return the "base" type from TYPE that is suitable to apply attribute
+ vector_size to by stripping arrays, function types, etc. */
static tree
-handle_vector_size_attribute (tree *node, tree name, tree args,
- int ARG_UNUSED (flags),
- bool *no_add_attrs)
+type_for_vector_size (tree type)
{
- unsigned HOST_WIDE_INT vecsize, nunits;
- machine_mode orig_mode;
- tree type = *node, new_type, size;
-
- *no_add_attrs = true;
-
- size = TREE_VALUE (args);
- if (size && TREE_CODE (size) != IDENTIFIER_NODE
- && TREE_CODE (size) != FUNCTION_DECL)
- size = default_conversion (size);
-
- if (!tree_fits_uhwi_p (size))
- {
- warning (OPT_Wattributes, "%qE attribute ignored", name);
- return NULL_TREE;
- }
-
- /* Get the vector size (in bytes). */
- vecsize = tree_to_uhwi (size);
-
/* We need to provide for vector pointers, vector arrays, and
functions returning vectors. For example:
|| TREE_CODE (type) == OFFSET_TYPE)
type = TREE_TYPE (type);
+ return type;
+}
+
+/* Given TYPE, return the base type to which the vector_size attribute
+ ATNAME with ARGS, when non-null, can be applied, if one exists.
+ On success and when both ARGS and PTRNUNITS are non-null, set
+ *PTRNUNINTS to the number of vector units. When PTRNUNITS is not
+ null, issue a warning when the attribute argument is not constant
+ and an error if there is no such type. Otherwise issue a warning
+ in the latter case and return null. */
+
+static tree
+type_valid_for_vector_size (tree type, tree atname, tree args,
+ unsigned HOST_WIDE_INT *ptrnunits)
+{
+ bool error_p = ptrnunits != NULL;
+
/* Get the mode of the type being modified. */
- orig_mode = TYPE_MODE (type);
+ machine_mode orig_mode = TYPE_MODE (type);
if ((!INTEGRAL_TYPE_P (type)
&& !SCALAR_FLOAT_TYPE_P (type)
|| !tree_fits_uhwi_p (TYPE_SIZE_UNIT (type))
|| TREE_CODE (type) == BOOLEAN_TYPE)
{
- error ("invalid vector type for attribute %qE", name);
+ if (error_p)
+ error ("invalid vector type for attribute %qE", atname);
+ else
+ warning (OPT_Wattributes, "invalid vector type for attribute %qE",
+ atname);
return NULL_TREE;
}
+ /* When no argument has been provided this is just a request to validate
+ the type above. Return TYPE to indicate success. */
+ if (!args)
+ return type;
+
+ tree size = TREE_VALUE (args);
+ if (size && TREE_CODE (size) != IDENTIFIER_NODE
+ && TREE_CODE (size) != FUNCTION_DECL)
+ size = default_conversion (size);
+
+ if (!tree_fits_uhwi_p (size))
+ {
+ /* FIXME: make the error message more informative. */
+ if (error_p)
+ warning (OPT_Wattributes, "%qE attribute ignored", atname);
+ return NULL_TREE;
+ }
+
+ unsigned HOST_WIDE_INT vecsize = tree_to_uhwi (size);
if (vecsize % tree_to_uhwi (TYPE_SIZE_UNIT (type)))
{
- error ("vector size not an integral multiple of component size");
- return NULL;
+ if (error_p)
+ error ("vector size not an integral multiple of component size");
+ return NULL_TREE;
}
if (vecsize == 0)
}
/* Calculate how many units fit in the vector. */
- nunits = vecsize / tree_to_uhwi (TYPE_SIZE_UNIT (type));
+ unsigned HOST_WIDE_INT nunits = vecsize / tree_to_uhwi (TYPE_SIZE_UNIT (type));
if (nunits & (nunits - 1))
{
- error ("number of components of the vector not a power of two");
+ if (error_p)
+ error ("number of components of the vector not a power of two");
+ else
+ warning (OPT_Wattributes,
+ "number of components of the vector not a power of two");
return NULL_TREE;
}
- new_type = build_vector_type (type, nunits);
+ if (ptrnunits)
+ *ptrnunits = nunits;
+
+ return type;
+}
+
+/* Handle a "vector_size" attribute; arguments as in
+ struct attribute_spec.handler. */
+
+static tree
+handle_vector_size_attribute (tree *node, tree name, tree args,
+ int ARG_UNUSED (flags),
+ bool *no_add_attrs)
+{
+ *no_add_attrs = true;
+
+ /* Determine the "base" type to apply the attribute to. */
+ tree type = type_for_vector_size (*node);
+
+ /* Get the vector size (in bytes) and let the function compute
+ the number of vector units. */
+ unsigned HOST_WIDE_INT nunits;
+ type = type_valid_for_vector_size (type, name, args, &nunits);
+ if (!type)
+ return NULL_TREE;
+
+ tree new_type = build_vector_type (type, nunits);
/* Build back pointers if needed. */
*node = lang_hooks.types.reconstruct_complex_type (*node, new_type);
/* Handle the "nonnull" attribute. */
static tree
-handle_nonnull_attribute (tree *node, tree ARG_UNUSED (name),
+handle_nonnull_attribute (tree *node, tree name,
tree args, int ARG_UNUSED (flags),
bool *no_add_attrs)
{
tree type = *node;
- unsigned HOST_WIDE_INT attr_arg_num;
/* If no arguments are specified, all pointer arguments should be
non-null. Verify a full prototype is given so that the arguments
return NULL_TREE;
}
- /* Argument list specified. Verify that each argument number references
- a pointer argument. */
- for (attr_arg_num = 1; args; attr_arg_num++, args = TREE_CHAIN (args))
+ for (int i = 1; args; ++i)
{
- unsigned HOST_WIDE_INT arg_num = 0, ck_num;
-
- tree arg = TREE_VALUE (args);
- if (arg && TREE_CODE (arg) != IDENTIFIER_NODE
- && TREE_CODE (arg) != FUNCTION_DECL)
- TREE_VALUE (args) = arg = default_conversion (arg);
-
- if (!get_nonnull_operand (arg, &arg_num))
+ tree pos = TREE_VALUE (args);
+ /* NEXT is null when the attribute includes just one argument.
+ That's used to tell positional_argument to avoid mentioning
+ the argument number in diagnostics (since there's just one
+ mentioning it is unnecessary and coule be confusing). */
+ tree next = TREE_CHAIN (args);
+ if (tree val = positional_argument (type, name, pos, POINTER_TYPE,
+ next || i > 1 ? i : 0))
+ TREE_VALUE (args) = val;
+ else
{
- error ("nonnull argument has invalid operand number (argument %lu)",
- (unsigned long) attr_arg_num);
*no_add_attrs = true;
- return NULL_TREE;
- }
-
- if (prototype_p (type))
- {
- function_args_iterator iter;
- tree argument;
-
- function_args_iter_init (&iter, type);
- for (ck_num = 1; ; ck_num++, function_args_iter_next (&iter))
- {
- argument = function_args_iter_cond (&iter);
- if (argument == NULL_TREE || ck_num == arg_num)
- break;
- }
-
- if (!argument
- || TREE_CODE (argument) == VOID_TYPE)
- {
- error ("nonnull argument with out-of-range operand number "
- "(argument %lu, operand %lu)",
- (unsigned long) attr_arg_num, (unsigned long) arg_num);
- *no_add_attrs = true;
- return NULL_TREE;
- }
-
- if (TREE_CODE (argument) != POINTER_TYPE)
- {
- error ("nonnull argument references non-pointer operand "
- "(argument %lu, operand %lu)",
- (unsigned long) attr_arg_num, (unsigned long) arg_num);
- *no_add_attrs = true;
- return NULL_TREE;
- }
+ break;
}
+ args = next;
}
return NULL_TREE;
/* Nothing to be done here. */
return NULL_TREE;
}
+
+/* Attempt to partially validate a single attribute ATTR as if
+ it were to be applied to an entity OPER. */
+
+static bool
+validate_attribute (location_t atloc, tree oper, tree attr)
+{
+ /* Determine whether the name of the attribute is valid
+ and fail with an error if not. */
+ tree atname = get_attribute_name (attr);
+ if (!lookup_attribute_spec (atname))
+ {
+ if (atloc != UNKNOWN_LOCATION)
+ error_at (atloc, "unknown attribute %qE", atname);
+ return false;
+ }
+
+ tree args = TREE_VALUE (attr);
+ if (!args)
+ return true;
+
+ /* FIXME: Do some validation. */
+ const char *atstr = IDENTIFIER_POINTER (atname);
+ if (!strcmp (atstr, "format"))
+ return true;
+
+ /* Only when attribute arguments have been provided try to validate
+ the whole thing. decl_attributes doesn't return an indication of
+ success or failure so proceed regardless. */
+ const char tmpname[] = "__builtin_has_attribute_tmp.";
+ tree tmpid = get_identifier (tmpname);
+ tree tmpdecl;
+ if (!strcmp (atstr, "vector_size"))
+ {
+ tree type = TYPE_P (oper) ? oper : TREE_TYPE (oper);
+ /* Check for function type here since type_for_vector_size
+ strips it while looking for a function's return type. */
+ if (FUNC_OR_METHOD_TYPE_P (type))
+ {
+ warning_at (atloc, OPT_Wattributes,
+ "invalid operand type %qT for %qs", type, atstr);
+ return false;
+ }
+
+ type = type_for_vector_size (type);
+ if (VECTOR_TYPE_P (type))
+ type = TREE_TYPE (type);
+ /* Avoid trying to apply attribute vector_size to OPER since
+ it's overly restrictive. Simply make sure it has the right
+ type. */
+ return type_valid_for_vector_size (type, atname, args, NULL);
+ }
+
+ if (TYPE_P (oper))
+ tmpdecl = build_decl (atloc, TYPE_DECL, tmpid, oper);
+ else
+ tmpdecl = build_decl (atloc, TREE_CODE (oper), tmpid, TREE_TYPE (oper));
+
+ /* Temporarily clear CURRENT_FUNCTION_DECL to make decl_attributes
+ believe the DECL declared above is at file scope. (See bug 87526.) */
+ tree save_curfunc = current_function_decl;
+ current_function_decl = NULL_TREE;
+ if (DECL_P (tmpdecl))
+ {
+ if (DECL_P (oper))
+ /* An alias cannot be a defintion so declare the symbol extern. */
+ DECL_EXTERNAL (tmpdecl) = true;
+ /* Attribute visibility only applies to symbols visible from other
+ translation units so make it "public." */
+ TREE_PUBLIC (tmpdecl) = TREE_PUBLIC (oper);
+ }
+ decl_attributes (&tmpdecl, attr, 0);
+ current_function_decl = save_curfunc;
+
+ /* FIXME: Change decl_attributes to indicate success or failure (and
+ parameterize it to avoid failing with errors). */
+ return true;
+}
+
+/* Return true if the DECL, EXPR, or TYPE t has been declared with
+ attribute ATTR. For DECL, consider also its type. For EXPR,
+ consider just its type. */
+
+bool
+has_attribute (location_t atloc, tree t, tree attr, tree (*convert)(tree))
+{
+ if (!attr || !t || t == error_mark_node)
+ return false;
+
+ if (!validate_attribute (atloc, t, attr))
+ return false;
+
+ tree type = NULL_TREE;
+ tree expr = NULL_TREE;
+ if (TYPE_P (t))
+ type = t;
+ else
+ {
+ do
+ {
+ /* Determine the array element/member declaration from
+ an ARRAY/COMPONENT_REF. */
+ STRIP_NOPS (t);
+ tree_code code = TREE_CODE (t);
+ if (code == ARRAY_REF)
+ t = TREE_OPERAND (t, 0);
+ else if (code == COMPONENT_REF)
+ t = TREE_OPERAND (t, 1);
+ else
+ break;
+ } while (true);
+ expr = t;
+ }
+
+ /* Set to true when an attribute is found in the referenced entity
+ that matches the specified attribute. */
+ bool found_match = false;
+
+ tree atname = get_attribute_name (attr);
+ const char *namestr = IDENTIFIER_POINTER (atname);
+
+ /* Iterate once for a type and twice for a function or variable
+ declaration: once for the DECL and the second time for its
+ TYPE. */
+ for (bool done = false; !found_match && !done; )
+ {
+ tree atlist;
+ if (type)
+ {
+ if (type == error_mark_node)
+ {
+ /* This could be a label. FIXME: add support for labels. */
+ warning_at (atloc, OPT_Wattributes,
+ (TYPE_P (t)
+ ? G_("%qs attribute not supported for %qT "
+ "in %<__builtin_has_attribute%>")
+ : G_("%qs attribute not supported for %qE "
+ "in %<__builtin_has_attribute%>")),
+ namestr, t);
+ return false;
+ }
+
+ /* Clear EXPR to prevent considering it again below. */
+ atlist = TYPE_ATTRIBUTES (type);
+ expr = NULL_TREE;
+ done = true;
+ }
+ else if (DECL_P (expr))
+ {
+ /* Set TYPE to the DECL's type to process it on the next
+ iteration. */
+ atlist = DECL_ATTRIBUTES (expr);
+ type = TREE_TYPE (expr);
+ }
+ else
+ {
+ atlist = TYPE_ATTRIBUTES (TREE_TYPE (expr));
+ done = true;
+ }
+
+ /* True when an attribute with the sought name (though not necessarily
+ with the sought attributes) has been found on the attribute chain. */
+ bool found_attr = false;
+
+ /* When clear, the first mismatched attribute argument results
+ in failure. Otherwise, the first matched attribute argument
+ results in success. */
+ bool attr_nonnull = !strcmp ("nonnull", namestr);
+ bool ignore_mismatches = attr_nonnull;
+
+ /* Iterate over the instances of the sought attribute on the DECL or
+ TYPE (there may be multiple instances with different arguments). */
+ for (; (atlist = lookup_attribute (namestr, atlist));
+ found_attr = true, atlist = TREE_CHAIN (atlist))
+ {
+ /* If there are no arguments to match the result is true except
+ for nonnull where the attribute with no arguments must match. */
+ if (!TREE_VALUE (attr))
+ return attr_nonnull ? !TREE_VALUE (atlist) : true;
+
+ /* Attribute nonnull with no arguments subsumes all values of
+ the attribute. FIXME: This is overly broad since it only
+ applies to pointer arguments, but querying non-pointer
+ arguments is diagnosed. */
+ if (!TREE_VALUE (atlist) && attr_nonnull)
+ return true;
+
+ /* Iterate over the DECL or TYPE attribute argument's values. */
+ for (tree val = TREE_VALUE (atlist); val; val = TREE_CHAIN (val))
+ {
+ /* Iterate over the arguments in the sought attribute comparing
+ their values to those specified for the DECL or TYPE. */
+ for (tree arg = TREE_VALUE (attr); arg; arg = TREE_CHAIN (arg))
+ {
+ tree v1 = TREE_VALUE (val);
+ tree v2 = TREE_VALUE (arg);
+ if (v1 == v2)
+ return true;
+
+ if (!v1 || !v2)
+ break;
+
+ if (TREE_CODE (v1) == IDENTIFIER_NODE
+ || TREE_CODE (v2) == IDENTIFIER_NODE)
+ /* Two identifiers are the same if their values are
+ equal (that's handled above). Otherwise ther are
+ either not the same or oneis not an identifier. */
+ return false;
+
+ /* Convert to make them equality-comparable. */
+ v1 = convert (v1);
+ v2 = convert (v2);
+
+ /* A positive value indicates equality, negative means
+ "don't know." */
+ if (simple_cst_equal (v1, v2) == 1)
+ return true;
+
+ if (!ignore_mismatches)
+ break;
+ }
+ }
+ }
+
+ if (!found_attr)
+ {
+ /* Some attributes are encoded directly in the tree node. */
+ if (!strcmp ("aligned", namestr))
+ {
+ if (tree arg = TREE_VALUE (attr))
+ {
+ arg = convert (TREE_VALUE (arg));
+ if (expr && DECL_P (expr)
+ && DECL_USER_ALIGN (expr)
+ && tree_fits_uhwi_p (arg))
+ found_match = DECL_ALIGN_UNIT (expr) == tree_to_uhwi (arg);
+ else if (type && TYPE_USER_ALIGN (type))
+ found_match = TYPE_ALIGN_UNIT (type) == tree_to_uhwi (arg);
+ }
+ else if (expr && DECL_P (expr))
+ found_match = DECL_USER_ALIGN (expr);
+ else if (type)
+ found_match = TYPE_USER_ALIGN (type);
+ }
+ else if (!strcmp ("const", namestr))
+ {
+ if (expr && DECL_P (expr))
+ found_match = TREE_READONLY (expr);
+ }
+ else if (!strcmp ("noreturn", namestr))
+ {
+ /* C11 _Noreturn sets the volatile bit without attaching
+ an attribute to the decl. */
+ if (expr
+ && DECL_P (expr)
+ && FUNC_OR_METHOD_TYPE_P (TREE_TYPE (expr)))
+ found_match = TREE_THIS_VOLATILE (expr);
+ }
+ else if (!strcmp ("pure", namestr))
+ {
+ if (expr && DECL_P (expr))
+ found_match = DECL_PURE_P (expr);
+ }
+ else if (!strcmp ("deprecated", namestr))
+ {
+ found_match = TREE_DEPRECATED (expr ? expr : type);
+ if (found_match)
+ return true;
+ }
+ else if (!strcmp ("vector_size", namestr))
+ {
+ if (!type)
+ continue;
+
+ /* Determine the base type from arrays, pointers, and such.
+ Fail if the base type is not a vector. */
+ type = type_for_vector_size (type);
+ if (!VECTOR_TYPE_P (type))
+ return false;
+
+ if (tree arg = TREE_VALUE (attr))
+ {
+ /* Compare the vector size argument for equality. */
+ arg = convert (TREE_VALUE (arg));
+ return tree_int_cst_equal (arg, TYPE_SIZE_UNIT (type)) == 1;
+ }
+ else
+ return true;
+ }
+ else if (!strcmp ("warn_if_not_aligned", namestr))
+ {
+ if (tree arg = TREE_VALUE (attr))
+ {
+ arg = convert (TREE_VALUE (arg));
+ if (expr && DECL_P (expr))
+ found_match = (DECL_WARN_IF_NOT_ALIGN (expr)
+ == tree_to_uhwi (arg) * BITS_PER_UNIT);
+ else if (type)
+ found_match = (TYPE_WARN_IF_NOT_ALIGN (type)
+ == tree_to_uhwi (arg) * BITS_PER_UNIT);
+ }
+ else if (expr && DECL_P (expr))
+ found_match = DECL_WARN_IF_NOT_ALIGN (expr);
+ else if (type)
+ found_match = TYPE_WARN_IF_NOT_ALIGN (type);
+ }
+ else if (!strcmp ("transparent_union", namestr))
+ {
+ if (type)
+ found_match = TYPE_TRANSPARENT_AGGR (type) != 0;
+ }
+ else if (!strcmp ("mode", namestr))
+ {
+ /* Finally issue a warning for attributes that cannot
+ be supported in this context. Attribute mode is not
+ added to a symbol and cannot be determined from it. */
+ warning_at (atloc, OPT_Wattributes,
+ "%qs attribute not supported in "
+ "%<__builtin_has_attribute%>", namestr);
+ break;
+ }
+ }
+ }
+ return found_match;
+}