/* Convert function calls to rtl insns, for GNU C compiler.
- Copyright (C) 1989-2019 Free Software Foundation, Inc.
+ Copyright (C) 1989-2020 Free Software Foundation, Inc.
This file is part of GCC.
#include "tree-ssa-strlen.h"
#include "intl.h"
#include "stringpool.h"
+#include "hash-map.h"
+#include "hash-traits.h"
#include "attribs.h"
#include "builtins.h"
#include "gimple-fold.h"
/* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
form for emit_group_move. */
rtx parallel_value;
- /* If value is passed in neither reg nor stack, this field holds a number
- of a special slot to be used. */
- rtx special_slot;
- /* For pointer bounds hold an index of parm bounds are bound to. -1 if
- there is no such pointer. */
- int pointer_arg;
- /* If pointer_arg refers a structure, then pointer_offset holds an offset
- of a pointer in this structure. */
- int pointer_offset;
/* If REG was promoted from the actual mode of the argument expression,
indicates whether the promotion is sign- or zero-extended. */
int unsignedp;
It is zero if this call doesn't want a structure value.
NEXT_ARG_REG is the rtx that results from executing
- targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
+ targetm.calls.function_arg (&args_so_far,
+ function_arg_info::end_marker ());
just after all the args have had their registers assigned.
This could be whatever you like, but normally it is the first
arg-register beyond those used for args in this call,
{
tree name_decl = DECL_NAME (fndecl);
- if (fndecl && name_decl
- && IDENTIFIER_LENGTH (name_decl) <= 11
- /* Exclude functions not at the file scope, or not `extern',
- since they are not the magic functions we would otherwise
- think they are.
- FIXME: this should be handled with attributes, not with this
- hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
- because you can declare fork() inside a function if you
- wish. */
- && (DECL_CONTEXT (fndecl) == NULL_TREE
- || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
- && TREE_PUBLIC (fndecl))
+ if (maybe_special_function_p (fndecl)
+ && IDENTIFIER_LENGTH (name_decl) <= 11)
{
const char *name = IDENTIFIER_POINTER (name_decl);
const char *tname = name;
return flags;
}
-/* Return true if TYPE should be passed by invisible reference. */
+/* Return true if ARG should be passed by invisible reference. */
bool
-pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
- tree type, bool named_arg)
+pass_by_reference (CUMULATIVE_ARGS *ca, function_arg_info arg)
{
- if (type)
+ if (tree type = arg.type)
{
/* If this type contains non-trivial constructors, then it is
forbidden for the middle-end to create any new copies. */
return true;
/* GCC post 3.4 passes *all* variable sized types by reference. */
- if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
+ if (!TYPE_SIZE (type) || !poly_int_tree_p (TYPE_SIZE (type)))
return true;
/* If a record type should be passed the same as its first (and only)
member, use the type and mode of that member. */
if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
{
- type = TREE_TYPE (first_field (type));
- mode = TYPE_MODE (type);
+ arg.type = TREE_TYPE (first_field (type));
+ arg.mode = TYPE_MODE (arg.type);
}
}
- return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
- type, named_arg);
+ return targetm.calls.pass_by_reference (pack_cumulative_args (ca), arg);
}
-/* Return true if TYPE, which is passed by reference, should be callee
+/* Return true if TYPE should be passed by reference when passed to
+ the "..." arguments of a function. */
+
+bool
+pass_va_arg_by_reference (tree type)
+{
+ return pass_by_reference (NULL, function_arg_info (type, /*named=*/false));
+}
+
+/* Decide whether ARG, which occurs in the state described by CA,
+ should be passed by reference. Return true if so and update
+ ARG accordingly. */
+
+bool
+apply_pass_by_reference_rules (CUMULATIVE_ARGS *ca, function_arg_info &arg)
+{
+ if (pass_by_reference (ca, arg))
+ {
+ arg.type = build_pointer_type (arg.type);
+ arg.mode = TYPE_MODE (arg.type);
+ arg.pass_by_reference = true;
+ return true;
+ }
+ return false;
+}
+
+/* Return true if ARG, which is passed by reference, should be callee
copied instead of caller copied. */
bool
-reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
- tree type, bool named_arg)
+reference_callee_copied (CUMULATIVE_ARGS *ca, const function_arg_info &arg)
{
- if (type && TREE_ADDRESSABLE (type))
+ if (arg.type && TREE_ADDRESSABLE (arg.type))
return false;
- return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
- named_arg);
+ return targetm.calls.callee_copies (pack_cumulative_args (ca), arg);
}
bool
get_size_range (tree exp, tree range[2], bool allow_zero /* = false */)
{
+ if (!exp)
+ return false;
+
if (tree_fits_uhwi_p (exp))
{
/* EXP is a constant. */
location_t loc = EXPR_LOCATION (exp);
tree fntype = fn ? TREE_TYPE (fn) : TREE_TYPE (TREE_TYPE (exp));
- built_in_function fncode = fn ? DECL_FUNCTION_CODE (fn) : BUILT_IN_NONE;
bool warned = false;
/* Validate each argument individually. */
friends.
Also avoid issuing the warning for calls to function named
"alloca". */
- if ((fncode == BUILT_IN_ALLOCA
- && IDENTIFIER_LENGTH (DECL_NAME (fn)) != 6)
- || (fncode != BUILT_IN_ALLOCA
- && !lookup_attribute ("returns_nonnull",
- TYPE_ATTRIBUTES (fntype))))
+ if (fn && fndecl_built_in_p (fn, BUILT_IN_ALLOCA)
+ ? IDENTIFIER_LENGTH (DECL_NAME (fn)) != 6
+ : !lookup_attribute ("returns_nonnull",
+ TYPE_ATTRIBUTES (fntype)))
warned = warning_at (loc, OPT_Walloc_zero,
"%Kargument %i value is zero",
exp, idx[i] + 1);
&& fn
&& !args[1]
&& lang_GNU_CXX ()
- && DECL_IS_OPERATOR_NEW (fn)
+ && DECL_IS_OPERATOR_NEW_P (fn)
&& integer_all_onesp (args[i]))
continue;
if (TREE_NO_WARNING (exp) || !warn_stringop_overflow)
return;
+ /* Avoid clearly invalid calls (more checking done below). */
unsigned nargs = call_expr_nargs (exp);
+ if (!nargs)
+ return;
/* The bound argument to a bounded string function like strncpy. */
tree bound = NULL_TREE;
- /* The range of lengths of a string argument to one of the comparison
- functions. If the length is less than the bound it is used instead. */
- tree lenrng[2] = { NULL_TREE, NULL_TREE };
+ /* The longest known or possible string argument to one of the comparison
+ functions. If the length is less than the bound it is used instead.
+ Since the length is only used for warning and not for code generation
+ disable strict mode in the calls to get_range_strlen below. */
+ tree maxlen = NULL_TREE;
/* It's safe to call "bounded" string functions with a non-string
argument since the functions provide an explicit bound for this
and to adjust the range of the bound of the bounded ones. */
for (unsigned argno = 0;
argno < MIN (nargs, 2)
- && !(lenrng[1] && TREE_CODE (lenrng[1]) == INTEGER_CST); argno++)
+ && !(maxlen && TREE_CODE (maxlen) == INTEGER_CST); argno++)
{
tree arg = CALL_EXPR_ARG (exp, argno);
if (!get_attr_nonstring_decl (arg))
- get_range_strlen (arg, lenrng);
+ {
+ c_strlen_data lendata = { };
+ /* Set MAXBOUND to an arbitrary non-null non-integer
+ node as a request to have it set to the length of
+ the longest string in a PHI. */
+ lendata.maxbound = arg;
+ get_range_strlen (arg, &lendata, /* eltsize = */ 1);
+ maxlen = lendata.maxbound;
+ }
}
}
/* Fall through. */
{
tree arg = CALL_EXPR_ARG (exp, 0);
if (!get_attr_nonstring_decl (arg))
- get_range_strlen (arg, lenrng);
-
+ {
+ c_strlen_data lendata = { };
+ /* Set MAXBOUND to an arbitrary non-null non-integer
+ node as a request to have it set to the length of
+ the longest string in a PHI. */
+ lendata.maxbound = arg;
+ get_range_strlen (arg, &lendata, /* eltsize = */ 1);
+ maxlen = lendata.maxbound;
+ }
if (nargs > 1)
bound = CALL_EXPR_ARG (exp, 1);
break;
}
}
- if (lenrng[1] && TREE_CODE (lenrng[1]) == INTEGER_CST)
+ if (maxlen && !integer_all_onesp (maxlen))
{
/* Add one for the nul. */
- lenrng[1] = const_binop (PLUS_EXPR, TREE_TYPE (lenrng[1]),
- lenrng[1], size_one_node);
+ maxlen = const_binop (PLUS_EXPR, TREE_TYPE (maxlen), maxlen,
+ size_one_node);
if (!bndrng[0])
{
/* Conservatively use the upper bound of the lengths for
both the lower and the upper bound of the operation. */
- bndrng[0] = lenrng[1];
- bndrng[1] = lenrng[1];
+ bndrng[0] = maxlen;
+ bndrng[1] = maxlen;
bound = void_type_node;
}
- else
+ else if (maxlen)
{
/* Replace the bound on the operation with the upper bound
of the length of the string if the latter is smaller. */
- if (tree_int_cst_lt (lenrng[1], bndrng[0]))
- bndrng[0] = lenrng[1];
- else if (tree_int_cst_lt (lenrng[1], bndrng[1]))
- bndrng[1] = lenrng[1];
+ if (tree_int_cst_lt (maxlen, bndrng[0]))
+ bndrng[0] = maxlen;
+ else if (tree_int_cst_lt (maxlen, bndrng[1]))
+ bndrng[1] = maxlen;
}
}
error_at (EXPR_LOCATION (call_expr), "cannot tail-call: %s", reason);
}
+/* Used to define rdwr_map below. */
+struct rdwr_access_hash: int_hash<int, -1> { };
+
+/* A mapping between argument number corresponding to attribute access
+ mode (read_only, write_only, or read_write) and operands. */
+typedef hash_map<rdwr_access_hash, attr_access> rdwr_map;
+
+/* Initialize a mapping for a call to function FNDECL declared with
+ attribute access. Each attribute positional operand inserts one
+ entry into the mapping with the operand number as the key. */
+
+static void
+init_attr_rdwr_indices (rdwr_map *rwm, tree fntype)
+{
+ if (!fntype)
+ return;
+
+ for (tree access = TYPE_ATTRIBUTES (fntype);
+ (access = lookup_attribute ("access", access));
+ access = TREE_CHAIN (access))
+ {
+ /* The TREE_VALUE of an attribute is a TREE_LIST whose TREE_VALUE
+ is the attribute argument's value. */
+ tree mode = TREE_VALUE (access);
+ gcc_assert (TREE_CODE (mode) == TREE_LIST);
+ mode = TREE_VALUE (mode);
+ gcc_assert (TREE_CODE (mode) == STRING_CST);
+
+ const char *modestr = TREE_STRING_POINTER (mode);
+ for (const char *m = modestr; *m; )
+ {
+ attr_access acc = { };
+
+ switch (*m)
+ {
+ case 'r': acc.mode = acc.read_only; break;
+ case 'w': acc.mode = acc.write_only; break;
+ default: acc.mode = acc.read_write; break;
+ }
+
+ char *end;
+ acc.ptrarg = strtoul (++m, &end, 10);
+ m = end;
+ if (*m == ',')
+ {
+ acc.sizarg = strtoul (++m, &end, 10);
+ m = end;
+ }
+ else
+ acc.sizarg = UINT_MAX;
+
+ acc.ptr = NULL_TREE;
+ acc.size = NULL_TREE;
+
+ /* Unconditionally add an entry for the required pointer
+ operand of the attribute, and one for the optional size
+ operand when it's specified. */
+ rwm->put (acc.ptrarg, acc);
+ if (acc.sizarg != UINT_MAX)
+ rwm->put (acc.sizarg, acc);
+ }
+ }
+}
+
+/* Returns the type of the argument ARGNO to function with type FNTYPE
+ or null when the typoe cannot be determined or no such argument exists. */
+
+static tree
+fntype_argno_type (tree fntype, unsigned argno)
+{
+ if (!prototype_p (fntype))
+ return NULL_TREE;
+
+ tree argtype;
+ function_args_iterator it;
+ FOREACH_FUNCTION_ARGS (fntype, argtype, it)
+ if (argno-- == 0)
+ return argtype;
+
+ return NULL_TREE;
+}
+
+/* Helper to append the "rdwr" attribute specification described
+ by ACCESS to the array ATTRSTR with size STRSIZE. Used in
+ diagnostics. */
+
+static inline void
+append_attrname (const std::pair<int, attr_access> &access,
+ char *attrstr, size_t strsize)
+{
+ /* Append the relevant attribute to the string. This (deliberately)
+ appends the attribute pointer operand even when none was specified. */
+ size_t len = strlen (attrstr);
+
+ const char *atname
+ = (access.second.mode == attr_access::read_only
+ ? "read_only"
+ : (access.second.mode == attr_access::write_only
+ ? "write_only" : "read_write"));
+
+ const char *sep = len ? ", " : "";
+
+ if (access.second.sizarg == UINT_MAX)
+ snprintf (attrstr + len, strsize - len,
+ "%s%s (%i)", sep, atname,
+ access.second.ptrarg + 1);
+ else
+ snprintf (attrstr + len, strsize - len,
+ "%s%s (%i, %i)", sep, atname,
+ access.second.ptrarg + 1, access.second.sizarg + 1);
+}
+
+/* Iterate over attribute access read-only, read-write, and write-only
+ arguments and diagnose past-the-end accesses and related problems
+ in the function call EXP. */
+
+static void
+maybe_warn_rdwr_sizes (rdwr_map *rwm, tree exp)
+{
+ tree fndecl = NULL_TREE;
+ tree fntype = NULL_TREE;
+ if (tree fnaddr = CALL_EXPR_FN (exp))
+ {
+ if (TREE_CODE (fnaddr) == ADDR_EXPR)
+ {
+ fndecl = TREE_OPERAND (fnaddr, 0);
+ fntype = TREE_TYPE (fndecl);
+ }
+ else
+ fntype = TREE_TYPE (TREE_TYPE (fnaddr));
+ }
+
+ if (!fntype)
+ return;
+
+ /* A string describing the attributes that the warnings issued by this
+ function apply to. Used to print one informational note per function
+ call, rather than one per warning. That reduces clutter. */
+ char attrstr[80];
+ attrstr[0] = 0;
+
+ for (rdwr_map::iterator it = rwm->begin (); it != rwm->end (); ++it)
+ {
+ std::pair<int, attr_access> access = *it;
+
+ /* Get the function call arguments corresponding to the attribute's
+ positional arguments. When both arguments have been specified
+ there will be two entries in *RWM, one for each. They are
+ cross-referenced by their respective argument numbers in
+ ACCESS.PTRARG and ACCESS.SIZARG. */
+ const int ptridx = access.second.ptrarg;
+ const int sizidx = access.second.sizarg;
+
+ gcc_assert (ptridx != -1);
+ gcc_assert (access.first == ptridx || access.first == sizidx);
+
+ /* The pointer is set to null for the entry corresponding to
+ the size argument. Skip it. It's handled when the entry
+ corresponding to the pointer argument comes up. */
+ if (!access.second.ptr)
+ continue;
+
+ tree argtype = fntype_argno_type (fntype, ptridx);
+ argtype = TREE_TYPE (argtype);
+
+ tree size;
+ if (sizidx == -1)
+ {
+ /* If only the pointer attribute operand was specified
+ and not size, set SIZE to the size of one element of
+ the pointed to type to detect smaller objects (null
+ pointers are diagnosed in this case only if
+ the pointer is also declared with attribute nonnull. */
+ size = size_one_node;
+ }
+ else
+ size = rwm->get (sizidx)->size;
+
+ tree ptr = access.second.ptr;
+ tree sizrng[2] = { size_zero_node, build_all_ones_cst (sizetype) };
+ if (get_size_range (size, sizrng, true)
+ && tree_int_cst_sgn (sizrng[0]) < 0
+ && tree_int_cst_sgn (sizrng[1]) < 0)
+ {
+ /* Warn about negative sizes. */
+ bool warned = false;
+ location_t loc = EXPR_LOCATION (exp);
+ if (tree_int_cst_equal (sizrng[0], sizrng[1]))
+ warned = warning_at (loc, OPT_Wstringop_overflow_,
+ "%Kargument %i value %E is negative",
+ exp, sizidx + 1, size);
+ else
+ warned = warning_at (loc, OPT_Wstringop_overflow_,
+ "%Kargument %i range [%E, %E] is negative",
+ exp, sizidx + 1, sizrng[0], sizrng[1]);
+ if (warned)
+ {
+ append_attrname (access, attrstr, sizeof attrstr);
+ /* Avoid warning again for the same attribute. */
+ continue;
+ }
+ }
+
+ if (tree_int_cst_sgn (sizrng[0]) >= 0)
+ {
+ if (COMPLETE_TYPE_P (argtype))
+ {
+ /* Multiple SIZE by the size of the type the pointer
+ argument points to. If it's incomplete the size
+ is used as is. */
+ size = NULL_TREE;
+ if (tree argsize = TYPE_SIZE_UNIT (argtype))
+ if (TREE_CODE (argsize) == INTEGER_CST)
+ {
+ const int prec = TYPE_PRECISION (sizetype);
+ wide_int minsize = wi::to_wide (sizrng[0], prec);
+ minsize *= wi::to_wide (argsize, prec);
+ size = wide_int_to_tree (sizetype, minsize);
+ }
+ }
+ }
+ else
+ size = NULL_TREE;
+
+ if (sizidx >= 0
+ && integer_zerop (ptr)
+ && tree_int_cst_sgn (sizrng[0]) > 0)
+ {
+ /* Warn about null pointers with positive sizes. This is
+ different from also declaring the pointer argument with
+ attribute nonnull when the function accepts null pointers
+ only when the corresponding size is zero. */
+ bool warned = false;
+ location_t loc = EXPR_LOCATION (exp);
+ if (tree_int_cst_equal (sizrng[0], sizrng[1]))
+ warned = warning_at (loc, OPT_Wnonnull,
+ "%Kargument %i is null but the corresponding "
+ "size argument %i value is %E",
+ exp, ptridx + 1, sizidx + 1, size);
+ else
+ warned = warning_at (loc, OPT_Wnonnull,
+ "%Kargument %i is null but the corresponding "
+ "size argument %i range is [%E, %E]",
+ exp, ptridx + 1, sizidx + 1,
+ sizrng[0], sizrng[1]);
+ if (warned)
+ {
+ append_attrname (access, attrstr, sizeof attrstr);
+ /* Avoid warning again for the same attribute. */
+ continue;
+ }
+ }
+
+ tree objsize = compute_objsize (ptr, 0);
+
+ tree srcsize;
+ if (access.second.mode == attr_access::write_only)
+ {
+ /* For a write-only argument there is no source. */
+ srcsize = NULL_TREE;
+ }
+ else
+ {
+ /* For read-only and read-write attributes also set the source
+ size. */
+ srcsize = objsize;
+ if (access.second.mode == attr_access::read_only)
+ {
+ /* For a read-only attribute there is no destination so
+ clear OBJSIZE. This emits "reading N bytes" kind of
+ diagnostics instead of the "writing N bytes" kind. */
+ objsize = NULL_TREE;
+ }
+ }
+
+ /* Clear the no-warning bit in case it was set in a prior
+ iteration so that accesses via different arguments are
+ diagnosed. */
+ TREE_NO_WARNING (exp) = false;
+ check_access (exp, NULL_TREE, NULL_TREE, size, /*maxread=*/ NULL_TREE,
+ srcsize, objsize);
+
+ if (TREE_NO_WARNING (exp))
+ /* If check_access issued a warning above, append the relevant
+ attribute to the string. */
+ append_attrname (access, attrstr, sizeof attrstr);
+ }
+
+ if (!*attrstr)
+ return;
+
+ if (fndecl)
+ inform (DECL_SOURCE_LOCATION (fndecl),
+ "in a call to function %qD declared with attribute %qs",
+ fndecl, attrstr);
+ else
+ inform (EXPR_LOCATION (fndecl),
+ "in a call with type %qT and attribute %qs",
+ fntype, attrstr);
+
+ /* Set the bit in case if was cleared and not set above. */
+ TREE_NO_WARNING (exp) = true;
+}
+
/* Fill in ARGS_SIZE and ARGS array based on the parameters found in
CALL_EXPR EXP.
/* Array for up to the two attribute alloc_size arguments. */
tree alloc_args[] = { NULL_TREE, NULL_TREE };
+ /* Map of attribute read_only, write_only, or read_write specifications
+ for function arguments. */
+ rdwr_map rdwr_idx;
+ init_attr_rdwr_indices (&rdwr_idx, fntype);
+
/* I counts args in order (to be) pushed; ARGPOS counts in order written. */
for (argpos = 0; argpos < num_actuals; i--, argpos++)
{
tree type = TREE_TYPE (args[i].tree_value);
int unsignedp;
- machine_mode mode;
/* Replace erroneous argument with constant zero. */
if (type == error_mark_node || !COMPLETE_TYPE_P (type))
/* If TYPE is a transparent union or record, pass things the way
we would pass the first field of the union or record. We have
already verified that the modes are the same. */
- if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
- && TYPE_TRANSPARENT_AGGR (type))
+ if (RECORD_OR_UNION_TYPE_P (type) && TYPE_TRANSPARENT_AGGR (type))
type = TREE_TYPE (first_field (type));
/* Decide where to pass this arg.
with those made by function.c. */
/* See if this argument should be passed by invisible reference. */
- if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
- type, argpos < n_named_args))
+ function_arg_info arg (type, argpos < n_named_args);
+ if (pass_by_reference (args_so_far_pnt, arg))
{
bool callee_copies;
tree base = NULL_TREE;
- callee_copies
- = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
- type, argpos < n_named_args);
+ callee_copies = reference_callee_copied (args_so_far_pnt, arg);
/* If we're compiling a thunk, pass through invisible references
instead of making a copy. */
"argument must be passed"
" by copying");
}
+ arg.pass_by_reference = true;
}
unsignedp = TYPE_UNSIGNED (type);
- mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
- fndecl ? TREE_TYPE (fndecl) : fntype, 0);
+ arg.type = type;
+ arg.mode
+ = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
+ fndecl ? TREE_TYPE (fndecl) : fntype, 0);
args[i].unsignedp = unsignedp;
- args[i].mode = mode;
+ args[i].mode = arg.mode;
targetm.calls.warn_parameter_passing_abi (args_so_far, type);
- args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
- argpos < n_named_args);
+ args[i].reg = targetm.calls.function_arg (args_so_far, arg);
if (args[i].reg && CONST_INT_P (args[i].reg))
- {
- args[i].special_slot = args[i].reg;
- args[i].reg = NULL;
- }
+ args[i].reg = NULL;
/* If this is a sibling call and the machine has register windows, the
register window has to be unwinded before calling the routine, so
arguments have to go into the incoming registers. */
if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
args[i].tail_call_reg
- = targetm.calls.function_incoming_arg (args_so_far, mode, type,
- argpos < n_named_args);
+ = targetm.calls.function_incoming_arg (args_so_far, arg);
else
args[i].tail_call_reg = args[i].reg;
if (args[i].reg)
- args[i].partial
- = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
- argpos < n_named_args);
+ args[i].partial = targetm.calls.arg_partial_bytes (args_so_far, arg);
- args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
+ args[i].pass_on_stack = targetm.calls.must_pass_in_stack (arg);
/* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
it means that we are to pass this arg in the register(s) designated
if (args[i].reg == 0 || args[i].partial != 0
|| reg_parm_stack_space > 0
|| args[i].pass_on_stack)
- locate_and_pad_parm (mode, type,
+ locate_and_pad_parm (arg.mode, type,
#ifdef STACK_PARMS_IN_REG_PARM_AREA
1,
#else
/* The argument is passed entirely in registers. See at which
end it should be padded. */
args[i].locate.where_pad =
- BLOCK_REG_PADDING (mode, type,
+ BLOCK_REG_PADDING (arg.mode, type,
int_size_in_bytes (type) <= UNITS_PER_WORD);
#endif
/* Increment ARGS_SO_FAR, which has info about which arg-registers
have been used, etc. */
- targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
- type, argpos < n_named_args);
+ /* ??? Traditionally we've passed TYPE_MODE here, instead of the
+ promoted_mode used for function_arg above. However, the
+ corresponding handling of incoming arguments in function.c
+ does pass the promoted mode. */
+ arg.mode = TYPE_MODE (type);
+ targetm.calls.function_arg_advance (args_so_far, arg);
/* Store argument values for functions decorated with attribute
alloc_size. */
alloc_args[0] = args[i].tree_value;
else if (argpos == alloc_idx[1])
alloc_args[1] = args[i].tree_value;
+
+ /* Save the actual argument that corresponds to the access attribute
+ operand for later processing. */
+ if (attr_access *access = rdwr_idx.get (argpos))
+ {
+ if (POINTER_TYPE_P (type))
+ {
+ access->ptr = args[i].tree_value;
+ gcc_assert (access->size == NULL_TREE);
+ }
+ else
+ {
+ access->size = args[i].tree_value;
+ gcc_assert (access->ptr == NULL_TREE);
+ }
+ }
}
if (alloc_args[0])
/* Detect passing non-string arguments to functions expecting
nul-terminated strings. */
maybe_warn_nonstring_arg (fndecl, exp);
+
+ /* Check read_only, write_only, and read_write arguments. */
+ maybe_warn_rdwr_sizes (&rdwr_idx, exp);
}
/* Update ARGS_SIZE to contain the total size for the argument block.
poly_int64 size = 0;
HOST_WIDE_INT const_size = 0;
rtx_insn *before_arg = get_last_insn ();
+ tree type = TREE_TYPE (args[i].tree_value);
+ if (RECORD_OR_UNION_TYPE_P (type) && TYPE_TRANSPARENT_AGGR (type))
+ type = TREE_TYPE (first_field (type));
/* Set non-negative if we must move a word at a time, even if
just one word (e.g, partial == 4 && mode == DFmode). Set
to -1 if we just use a normal move insn. This value can be
gcc_assert (partial % UNITS_PER_WORD == 0);
nregs = partial / UNITS_PER_WORD;
}
- else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
+ else if (TYPE_MODE (type) == BLKmode)
{
/* Variable-sized parameters should be described by a
PARALLEL instead. */
- const_size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
+ const_size = int_size_in_bytes (type);
gcc_assert (const_size >= 0);
nregs = (const_size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
size = const_size;
if (GET_CODE (reg) == PARALLEL)
use_group_regs (call_fusage, reg);
else if (nregs == -1)
- use_reg_mode (call_fusage, reg,
- TYPE_MODE (TREE_TYPE (args[i].tree_value)));
+ use_reg_mode (call_fusage, reg, TYPE_MODE (type));
else if (nregs > 0)
use_regs (call_fusage, REGNO (reg), nregs);
}
}
#ifdef REG_PARM_STACK_SPACE
- /* If outgoing reg parm stack space changes, we can not do sibcall. */
+ /* If outgoing reg parm stack space changes, we cannot do sibcall. */
if (OUTGOING_REG_PARM_STACK_SPACE (funtype)
!= OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl))
|| (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl)))
return true;
}
+/* Update stack alignment when the parameter is passed in the stack
+ since the outgoing parameter requires extra alignment on the calling
+ function side. */
+
+static void
+update_stack_alignment_for_call (struct locate_and_pad_arg_data *locate)
+{
+ if (crtl->stack_alignment_needed < locate->boundary)
+ crtl->stack_alignment_needed = locate->boundary;
+ if (crtl->preferred_stack_boundary < locate->boundary)
+ crtl->preferred_stack_boundary = locate->boundary;
+}
+
/* Generate all the code for a CALL_EXPR exp
and return an rtx for its value.
Store the value in TARGET (specified as an rtx) if convenient.
|| dbg_cnt (tail_call) == false)
try_tail_call = 0;
+ /* Workaround buggy C/C++ wrappers around Fortran routines with
+ character(len=constant) arguments if the hidden string length arguments
+ are passed on the stack; if the callers forget to pass those arguments,
+ attempting to tail call in such routines leads to stack corruption.
+ Avoid tail calls in functions where at least one such hidden string
+ length argument is passed (partially or fully) on the stack in the
+ caller and the callee needs to pass any arguments on the stack.
+ See PR90329. */
+ if (try_tail_call && maybe_ne (args_size.constant, 0))
+ for (tree arg = DECL_ARGUMENTS (current_function_decl);
+ arg; arg = DECL_CHAIN (arg))
+ if (DECL_HIDDEN_STRING_LENGTH (arg) && DECL_INCOMING_RTL (arg))
+ {
+ subrtx_iterator::array_type array;
+ FOR_EACH_SUBRTX (iter, array, DECL_INCOMING_RTL (arg), NONCONST)
+ if (MEM_P (*iter))
+ {
+ try_tail_call = 0;
+ break;
+ }
+ }
+
/* If the user has marked the function as requiring tail-call
optimization, attempt it. */
if (must_tail_call)
/* Ensure current function's preferred stack boundary is at least
what we need. Stack alignment may also increase preferred stack
boundary. */
+ for (i = 0; i < num_actuals; i++)
+ if (reg_parm_stack_space > 0
+ || args[i].reg == 0
+ || args[i].partial != 0
+ || args[i].pass_on_stack)
+ update_stack_alignment_for_call (&args[i].locate);
if (crtl->preferred_stack_boundary < preferred_stack_boundary)
crtl->preferred_stack_boundary = preferred_stack_boundary;
else
preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
+ if (flag_callgraph_info)
+ record_final_call (fndecl, EXPR_LOCATION (exp));
+
/* We want to make two insn chains; one for a sibling call, the other
for a normal call. We will select one of the two chains after
initial RTL generation is complete. */
/* Set up next argument register. For sibling calls on machines
with register windows this should be the incoming register. */
if (pass == 0)
- next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
- VOIDmode,
- void_type_node,
- true);
+ next_arg_reg = targetm.calls.function_incoming_arg
+ (args_so_far, function_arg_info::end_marker ());
else
- next_arg_reg = targetm.calls.function_arg (args_so_far,
- VOIDmode, void_type_node,
- true);
+ next_arg_reg = targetm.calls.function_arg
+ (args_so_far, function_arg_info::end_marker ());
if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
{
emit_move_insn (temp, valreg);
- /* The return value from a malloc-like function can not alias
+ /* The return value from a malloc-like function cannot alias
anything else. */
last = get_last_insn ();
add_reg_note (last, REG_NOALIAS, temp);
argvec[count].mode = Pmode;
argvec[count].partial = 0;
- argvec[count].reg = targetm.calls.function_arg (args_so_far,
- Pmode, NULL_TREE, true);
- gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
- NULL_TREE, 1) == 0);
+ function_arg_info ptr_arg (Pmode, /*named=*/true);
+ argvec[count].reg = targetm.calls.function_arg (args_so_far, ptr_arg);
+ gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, ptr_arg) == 0);
locate_and_pad_parm (Pmode, NULL_TREE,
#ifdef STACK_PARMS_IN_REG_PARM_AREA
|| reg_parm_stack_space > 0)
args_size.constant += argvec[count].locate.size.constant;
- targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
+ targetm.calls.function_arg_advance (args_so_far, ptr_arg);
count++;
}
for (unsigned int i = 0; count < nargs; i++, count++)
{
rtx val = args[i].first;
- machine_mode mode = args[i].second;
+ function_arg_info arg (args[i].second, /*named=*/true);
int unsigned_p = 0;
/* We cannot convert the arg value to the mode the library wants here;
must do it earlier where we know the signedness of the arg. */
- gcc_assert (mode != BLKmode
- && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
+ gcc_assert (arg.mode != BLKmode
+ && (GET_MODE (val) == arg.mode
+ || GET_MODE (val) == VOIDmode));
/* Make sure it is a reasonable operand for a move or push insn. */
if (!REG_P (val) && !MEM_P (val)
- && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
+ && !(CONSTANT_P (val)
+ && targetm.legitimate_constant_p (arg.mode, val)))
val = force_operand (val, NULL_RTX);
- if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
+ if (pass_by_reference (&args_so_far_v, arg))
{
rtx slot;
- int must_copy
- = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
+ int must_copy = !reference_callee_copied (&args_so_far_v, arg);
/* If this was a CONST function, it is now PURE since it now
reads memory. */
}
else
{
- slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
+ slot = assign_temp (lang_hooks.types.type_for_mode (arg.mode, 0),
1, 1);
emit_move_insn (slot, val);
}
slot),
call_fusage);
- mode = Pmode;
+ arg.mode = Pmode;
+ arg.pass_by_reference = true;
val = force_operand (XEXP (slot, 0), NULL_RTX);
}
- mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
- argvec[count].mode = mode;
- argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
- argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
- NULL_TREE, true);
+ arg.mode = promote_function_mode (NULL_TREE, arg.mode, &unsigned_p,
+ NULL_TREE, 0);
+ argvec[count].mode = arg.mode;
+ argvec[count].value = convert_modes (arg.mode, GET_MODE (val), val,
+ unsigned_p);
+ argvec[count].reg = targetm.calls.function_arg (args_so_far, arg);
argvec[count].partial
- = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
+ = targetm.calls.arg_partial_bytes (args_so_far, arg);
if (argvec[count].reg == 0
|| argvec[count].partial != 0
|| reg_parm_stack_space > 0)
{
- locate_and_pad_parm (mode, NULL_TREE,
+ locate_and_pad_parm (arg.mode, NULL_TREE,
#ifdef STACK_PARMS_IN_REG_PARM_AREA
1,
#else
/* The argument is passed entirely in registers. See at which
end it should be padded. */
argvec[count].locate.where_pad =
- BLOCK_REG_PADDING (mode, NULL_TREE,
- known_le (GET_MODE_SIZE (mode), UNITS_PER_WORD));
+ BLOCK_REG_PADDING (arg.mode, NULL_TREE,
+ known_le (GET_MODE_SIZE (arg.mode),
+ UNITS_PER_WORD));
#endif
- targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
+ targetm.calls.function_arg_advance (args_so_far, arg);
}
+ for (int i = 0; i < nargs; i++)
+ if (reg_parm_stack_space > 0
+ || argvec[i].reg == 0
+ || argvec[i].partial != 0)
+ update_stack_alignment_for_call (&argvec[i].locate);
+
/* If this machine requires an external definition for library
functions, write one out. */
assemble_external_libcall (fun);
before_call = get_last_insn ();
+ if (flag_callgraph_info)
+ record_final_call (SYMBOL_REF_DECL (orgfun), UNKNOWN_LOCATION);
+
/* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
will set inhibit_defer_pop to that value. */
/* The return type is needed to decide how many bytes the function pops.
original_args_size.constant, args_size.constant,
struct_value_size,
targetm.calls.function_arg (args_so_far,
- VOIDmode, void_type_node, true),
+ function_arg_info::end_marker ()),
valreg,
old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
return sibcall_failure;
}
-/* Nonzero if we do not know how to pass TYPE solely in registers. */
+/* Nonzero if we do not know how to pass ARG solely in registers. */
bool
-must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
- const_tree type)
+must_pass_in_stack_var_size (const function_arg_info &arg)
{
- if (!type)
+ if (!arg.type)
return false;
/* If the type has variable size... */
- if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
+ if (!poly_int_tree_p (TYPE_SIZE (arg.type)))
return true;
/* If the type is marked as addressable (it is required
to be constructed into the stack)... */
- if (TREE_ADDRESSABLE (type))
+ if (TREE_ADDRESSABLE (arg.type))
return true;
return false;
/* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
bool
-must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
+must_pass_in_stack_var_size_or_pad (const function_arg_info &arg)
{
- if (!type)
+ if (!arg.type)
return false;
/* If the type has variable size... */
- if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
+ if (TREE_CODE (TYPE_SIZE (arg.type)) != INTEGER_CST)
return true;
/* If the type is marked as addressable (it is required
to be constructed into the stack)... */
- if (TREE_ADDRESSABLE (type))
+ if (TREE_ADDRESSABLE (arg.type))
return true;
- if (TYPE_EMPTY_P (type))
+ if (TYPE_EMPTY_P (arg.type))
return false;
/* If the padding and mode of the type is such that a copy into
a register would put it into the wrong part of the register. */
- if (mode == BLKmode
- && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
- && (targetm.calls.function_arg_padding (mode, type)
+ if (arg.mode == BLKmode
+ && int_size_in_bytes (arg.type) % (PARM_BOUNDARY / BITS_PER_UNIT)
+ && (targetm.calls.function_arg_padding (arg.mode, arg.type)
== (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
return true;
return false;
}
+/* Return true if TYPE must be passed on the stack when passed to
+ the "..." arguments of a function. */
+
+bool
+must_pass_va_arg_in_stack (tree type)
+{
+ function_arg_info arg (type, /*named=*/false);
+ return targetm.calls.must_pass_in_stack (arg);
+}
+
+/* Return true if FIELD is the C++17 empty base field that should
+ be ignored for ABI calling convention decisions in order to
+ maintain ABI compatibility between C++14 and earlier, which doesn't
+ add this FIELD to classes with empty bases, and C++17 and later
+ which does. */
+
+bool
+cxx17_empty_base_field_p (const_tree field)
+{
+ return (DECL_FIELD_ABI_IGNORED (field)
+ && DECL_ARTIFICIAL (field)
+ && RECORD_OR_UNION_TYPE_P (TREE_TYPE (field))
+ && !lookup_attribute ("no_unique_address", DECL_ATTRIBUTES (field)));
+}
+
/* Tell the garbage collector about GTY markers in this source file. */
#include "gt-calls.h"
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