-@c Copyright (C) 1988,1989,1992,1993,1994,1995,1996,1997,1998,1999,2000 Free Software Foundation, Inc.
+@c Copyright (C) 1988,1989,1992,1993,1994,1995,1996,1997,1998,1999,2000
+@c Free Software Foundation, Inc.
@c This is part of the GCC manual.
@c For copying conditions, see the file gcc.texi.
which are not accessible to the preprocessor. Otherwise, it should not
be defined.
+@findex NO_BUILTIN_WCHAR_TYPE
+@item NO_BUILTIN_WCHAR_TYPE
+If this macro is defined, the preprocessor will not define the builtin macro
+@code{__WCHAR_TYPE__}. The macro @code{__WCHAR_TYPE__} must then be
+defined by @code{CPP_SPEC} instead.
+
+This should be defined if @code{WCHAR_TYPE} depends on target dependent flags
+which are not accessible to the preprocessor. Otherwise, it should not
+be defined.
+
@findex SIGNED_CHAR_SPEC
@item SIGNED_CHAR_SPEC
A C string constant that tells the GCC driver program options to
The definition should be an initializer for an array of structures.
Each array element should have four elements: the directory name (a
-string constant), the component name, and flag for C++-only directories,
+string constant), the component name (also a string constant), a flag
+for C++-only directories,
and a flag showing that the includes in the directory don't need to be
wrapped in @code{extern @samp{C}} when compiling C++. Mark the end of
the array with a null element.
The component name denotes what GNU package the include file is part of,
if any, in all upper-case letters. For example, it might be @samp{GCC}
-or @samp{BINUTILS}. If the package is part of the a vendor-supplied
+or @samp{BINUTILS}. If the package is part of a vendor-supplied
operating system, code the component name as @samp{0}.
-@findex STRUCT_FORCE_BLK
-@item STRUCT_FORCE_BLK (@var{field})
-Return 1 if a structure containing @var{field} should be accessed using
-@code{BLKMODE}.
-
-Normally, this is not needed. See the file @file{c4x.h} for an example
-of how to use this macro to prevent a structure having a floating point
-field from being accessed in an integer mode.
-
-
For example, here is the definition used for VAX/VMS:
@example
@code{target_flags}.
Define a macro @code{TARGET_@var{featurename}} for each such option.
-Its definition should test a bit in @code{target_flags}; for example:
+Its definition should test a bit in @code{target_flags}. It is
+recommended that a helper macro @code{TARGET_MASK_@var{featurename}}
+is defined for each bit-value to test, and used in
+@code{TARGET_@var{featurename}} and @code{TARGET_SWITCHES}. For
+example:
@smallexample
-#define TARGET_68020 (target_flags & 1)
+#define TARGET_MASK_68020 1
+#define TARGET_68020 (target_flags & TARGET_MASK_68020)
@end smallexample
One place where these macros are used is in the condition-expressions
@smallexample
#define TARGET_SWITCHES \
- @{ @{ "68020", 1, "" @}, \
- @{ "68000", -1, "Compile for the 68000" @}, \
- @{ "", 1, "" @}@}
+ @{ @{ "68020", TARGET_MASK_68020, "" @}, \
+ @{ "68000", -TARGET_MASK_68020, "Compile for the 68000" @}, \
+ @{ "", TARGET_MASK_68020, "" @}@}
@end smallexample
@findex TARGET_OPTIONS
Like PCC_BITFIELD_TYPE_MATTERS except that its effect is limited to
aligning a bitfield within the structure.
+@findex STRUCT_FORCE_BLK
+@item STRUCT_FORCE_BLK (@var{field})
+Return 1 if a structure containing @var{field} should be accessed using
+@code{BLKMODE}.
+
+Normally, this is not needed. See the file @file{c4x.h} for an example
+of how to use this macro to prevent a structure having a floating point
+field from being accessed in an integer mode.
+
@findex ROUND_TYPE_SIZE
@item ROUND_TYPE_SIZE (@var{type}, @var{computed}, @var{specified})
Define this macro as an expression for the overall size of a type
The default is to round @var{computed} up to a multiple of @var{specified}.
+@findex ROUND_TYPE_SIZE_UNIT
+@item ROUND_TYPE_SIZE_UNIT (@var{type}, @var{computed}, @var{specified})
+Similar to @code{ROUND_TYPE_SIZE}, but sizes and alignments are
+specified in units (bytes). If you define @code{ROUND_TYPE_SIZE},
+you must also define this macro and they must be defined consistently
+with each other.
+
@findex ROUND_TYPE_ALIGN
@item ROUND_TYPE_ALIGN (@var{type}, @var{computed}, @var{specified})
Define this macro as an expression for the alignment of a type (given
@table @code
@findex LEAF_REGISTERS
@item LEAF_REGISTERS
-A C initializer for a vector, indexed by hard register number, which
+Name of a char vector, indexed by hard register number, which
contains 1 for a register that is allowable in a candidate for leaf
function treatment.
* Caller Saves::
* Function Entry::
* Profiling::
+* Inlining::
@end menu
@node Frame Layout
You only need to define this macro if you want to support call frame
debugging information like that provided by DWARF 2.
+If this RTL is a @code{REG}, you should also define
+DWARF_FRAME_RETURN_COLUMN to @code{DWARF_FRAME_REGNUM (REGNO)}.
+
@findex INCOMING_FRAME_SP_OFFSET
@item INCOMING_FRAME_SP_OFFSET
A C expression whose value is an integer giving the offset, in bytes,
debugging information like that provided by DWARF 2.
@findex ARG_POINTER_CFA_OFFSET
-@item ARG_POINTER_CFA_OFFSET
+@item ARG_POINTER_CFA_OFFSET (@var{fundecl})
A C expression whose value is an integer giving the offset, in bytes,
from the argument pointer to the canonical frame address (cfa). The
final value should coincide with that calculated by
@code{INCOMING_FRAME_SP_OFFSET}. Which is unfortunately not usable
during virtual register instantiation.
-You only need to define this macro if you want to support call frame
-debugging information like that provided by DWARF 2.
+The default value for this macro is @code{FIRST_PARM_OFFSET (fundecl)},
+which is correct for most machines; in general, the arguments are found
+immediately before the stack frame. Note that this is not the case on
+some targets that save registers into the caller's frame, such as SPARC
+and rs6000, and so such targets need to define this macro.
+
+You only need to define this macro if the default is incorrect, and you
+want to support call frame debugging information like that provided by
+DWARF 2.
@findex SMALL_STACK
@item SMALL_STACK
code on certain machines. If the macro is not defined in target
header files, it defaults to 0.
+@findex PUSH_ARGS
+@item PUSH_ARGS
+A C expression. If nonzero, push insns will be used to pass
+outgoing arguments.
+If the target machine does not have a push instruction, set it to zero.
+That directs GCC to use an alternate strategy: to
+allocate the entire argument block and then store the arguments into
+it. When PUSH_ARGS is nonzero, PUSH_ROUNDING must be defined too.
+On some machines, the definition
+
+@findex PUSH_ROUNDING
+@item PUSH_ROUNDING (@var{npushed})
+A C expression that is the number of bytes actually pushed onto the
+stack when an instruction attempts to push @var{npushed} bytes.
@findex PUSH_ROUNDING
@item PUSH_ROUNDING (@var{npushed})
A C expression that is the number of bytes actually pushed onto the
stack when an instruction attempts to push @var{npushed} bytes.
-
-If the target machine does not have a push instruction, do not define
-this macro. That directs GCC to use an alternate strategy: to
-allocate the entire argument block and then store the arguments into
-it.
On some machines, the definition
@findex ACCUMULATE_OUTGOING_ARGS
@findex current_function_outgoing_args_size
@item ACCUMULATE_OUTGOING_ARGS
-If defined, the maximum amount of space required for outgoing arguments
+A C expression. If nonzero, the maximum amount of space required for outgoing arguments
will be computed and placed into the variable
@code{current_function_outgoing_args_size}. No space will be pushed
onto the stack for each call; instead, the function prologue should
increase the stack frame size by this amount.
-Defining both @code{PUSH_ROUNDING} and @code{ACCUMULATE_OUTGOING_ARGS}
+Setting both @code{PUSH_ARGS} and @code{ACCUMULATE_OUTGOING_ARGS}
is not proper.
@findex REG_PARM_STACK_SPACE
support block profiling.
@end table
+@node Inlining
+@subsection Permitting inlining of functions with attributes
+@cindex inlining
+
+By default if a function has a target specific attribute attached to it,
+it will not be inlined. This behaviour can be overridden if the target
+defines the @samp{FUNCTION_ATTRIBUTE_INLINABLE_P} macro. This macro
+takes one argument, a @samp{DECL} describing the function. It should
+return non-zero if the function can be inlined, otherwise it should
+return 0.
+
@node Varargs
@section Implementing the Varargs Macros
@cindex varargs implementation
@findex TARGET_HAS_F_SETLKW
@item TARGET_HAS_F_SETLKW
-Define this macro iff the target supports file locking with fcntl / F_SETLKW.
+Define this macro if the target supports file locking with fcntl / F_SETLKW.
Note that this functionality is part of POSIX.
Defining @code{TARGET_HAS_F_SETLKW} will enable the test coverage code
to use file locking when exiting a program, which avoids race conditions
if the program has forked.
+
+@findex MAX_CONDITIONAL_EXECUTE
+@item MAX_CONDITIONAL_EXECUTE
+
+A C expression for the maximum number of instructions to execute via
+conditional execution instructions instead of a branch. A value of
+@code{BRANCH_COST}+1 is the default if the machine does not use cc0, and
+1 if it does use cc0.
@end table
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