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/* Output variables, constants and external declarations, for GNU compiler.
Copyright (C) 1988, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
This file is part of GNU CC.
GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#define VMS_TARGET
/* This enables certain macros in vax.h, which will make an indirect
reference to an external symbol an invalid address. This needs to be
defined before we include vax.h, since it determines which macros
are used for GO_IF_*. */
#include "vax/vax.h"
#undef LIB_SPEC
/* Predefine this in CPP because VMS limits the size of command options
and GNU CPP is not used on VMS except with GNU C. */
"-Dvax -Dvms -DVMS -D__vax__ -D__vms__ -D__VMS__\
-D__GNUC__=2 -D__GNUC_MINOR__=7 -Asystem(vms) -Acpu(vax) -Amachine(vax)"
/* These match the definitions used in VAXCRTL, the VMS C run-time library */
#define SIZE_TYPE "unsigned int"
#define PTRDIFF_TYPE "int"
#define WCHAR_TYPE "unsigned int"
#define WCHAR_TYPE_SIZE 32 /* in bits */
/* Use memcpy for structure copying, and so forth. */
/* Strictly speaking, VMS does not use DBX at all, but the interpreter built
into gas only speaks straight DBX. */
#define TARGET_NAME "vax/vms"
/* The structure return address arrives as an "argument" on VMS. */
#define STRUCT_VALUE 0
#define CALL_USED_REGISTERS {1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1}
/* The run-time library routine VAXC$ESTABLISH (necessary when mixing
VMS exception handling and setjmp/longjmp in the same program) requires
that a hidden automatic variable at the top of the stack be reserved
for its use. We accomplish this by simply adding 4 bytes to the local
stack for all functions, and making sure that normal local variables
are 4 bytes lower on the stack then they would otherwise have been. */
#define __MAIN_NAME " main("
* The MAYBE_VMS_FUNCTION_PROLOGUE macro works for both gcc and g++. It
* first checks to see if the current routine is "main", which will only
* happen for GCC, and add the jsb if it is. If is not the case then try and
* see if __MAIN_NAME is part of current_function_name, which will only happen
* if we are running g++, and add the jsb if it is. In gcc there should never
* be a paren in the function name, and in g++ there is always a "(" in the
* function name, thus there should never be any confusion.
* Adjusting the stack pointer by 4 before calling C$MAIN_ARGS is required
* when linking with the VMS POSIX version of the C run-time library; using
* `subl2 $4,r0' is adequate but we use `clrl -(sp)' instead. The extra 4
* bytes could be removed after the call because STARTING_FRAME_OFFSET's
* setting of -4 will end up adding them right back again, but don't bother.
{ extern char *current_function_name; \
char *p = current_function_name; \
int is_main = strcmp ("main", p) == 0; \
while (!is_main && *p != '\0') \
{ \
if (*p == *__MAIN_NAME \
&& strncmp (p, __MAIN_NAME, sizeof __MAIN_NAME - sizeof "") == 0) \
is_main = 1; \
else \
p++; \
} \
if (is_main) \
fprintf (FILE, "\t%s\n\t%s\n", "clrl -(sp)", "jsb _C$MAIN_ARGS"); \
/* This macro definition sets up a default value for `main' to return. */
#define DEFAULT_MAIN_RETURN c_expand_return (integer_one_node)
/* This makes use of a hook in varasm.c to mark all external variables
for us. We use this to make sure that external variables are correctly
addressed. Under VMS there is some brain damage in the linker that requires
us to do this. */
#define ENCODE_SECTION_INFO(decl) \
if (DECL_EXTERNAL (decl) && TREE_PUBLIC (decl)) \
SYMBOL_REF_FLAG (XEXP (DECL_RTL (decl), 0)) = 1;
/* This is how to output a command to make the user-level label named NAME
defined for reference from other files. */
do { fputs (".globl ", FILE); \
assemble_name (FILE, NAME); \
fputs ("\n", FILE); \
vms_check_external (NULL_TREE, NAME, 0); \
} while (0)
/* Under VMS we write the actual size of the storage to be allocated even
though the symbol is external. Although it is possible to give external
symbols a size of 0 (as unix does), the VMS linker does not make the
distinction between a variable definition and an external reference of a
variable, and thus the linker will not complain about a missing definition.
If we followed the unix example of giving external symbols a size of
zero, you tried to link a program where a given variable was externally
defined but none of the object modules contained a non-extern definition,
the linker would allocate 0 bytes for the variable, and any attempt to
use that variable would use the storage allocated to some other variable.
We must also select either const_section or data_section: this will indicate
whether or not the variable will get the readonly bit set. Since the
VMS linker does not distinguish between a variable's definition and an
external reference, all usages of a given variable must have the readonly
bit set the same way, or the linker will get confused and give warning
messages. */
/* We used to round the size up to a multiple of 4,
but that causes linker errors sometimes when the variable was initialized
since the size of its definition was not likewise rounded up. */
/* Note: the original ASM_OUTPUT_EXTERNAL code has been moved into
vms_check_external and vms_flush_pending_externals. */
vms_check_external ((DECL), (NAME), 1); \
/* ASM_OUTPUT_EXTERNAL will have wait until after an initializer is
completed in order to switch sections for an external object, so
use the DECLARE_OBJECT hooks to manage deferred declarations. */
/* This is the default action for ASM_DECLARE_OBJECT_NAME, but if it
is explicitly defined, then ASM_FINISH_DECLARE_OBJECT will be used. */
/* We don't need to do anything special to finish the current object, but it
should now be safe to output any deferred external global declarations. */
/* Anything still pending must be flushed at the very end. */
/* Here we redefine ASM_OUTPUT_COMMON to select the data_section or the
const_section before writing the ".const" assembler directive.
If we were specifying a size of zero for external variables, we would
not have to select a section, since the assembler can assume that
when the size > 0, the storage is for a non-external, uninitialized
variable (for which a "const" declaration would be senseless),
and the assembler can make the storage read/write.
Since the ".const" directive specifies the actual size of the storage used
for both external and non-external variables, the assembler cannot
make this assumption, and thus it has no way of deciding if storage should
be read/write or read-only. To resolve this, we give the assembler some
assistance, in the form of a ".const" or a ".data" directive.
Under GCC 1.40, external variables were declared with a size of zero.
The GNU assembler, GAS, will recognize the "-2" switch when built for VMS;
when compiling programs with GCC 2.n this switch should be used or the
assembler will not give the read-only attribute to external constants.
Failure to use this switch will result in linker warning messages about
mismatched psect attributes. */
( ((TREE_READONLY (decl) && ! TREE_THIS_VOLATILE (decl)) \
? (const_section (), 0) : (data_section (), 0)), \
fputs (".comm ", (FILE)), \
assemble_name ((FILE), (NAME)), \
fprintf ((FILE), ",%u\n", (SIZE)))
/* We define this to prevent the name mangler from putting dollar signs into
function names. This isn't really needed, but it has been here for
some time and removing it would cause the object files generated by the
compiler to be incompatible with the object files from a compiler that
had this defined. Since it does no harm, we leave it in. */
/* Add a "const" section. This is viewed by the assembler as being nearly
the same as the "data" section, with the only difference being that a
flag is set for variables declared while in the const section. This
flag is used to determine whether or not the read/write bit should be
set in the Psect definition. */
#define EXTRA_SECTIONS in_const
void \
const_section () \
{ \
if (in_section != in_const) { \
fprintf(asm_out_file,".const\n"); \
in_section = in_const; \
} \
/* This macro contains the logic to decide which section a variable
should be stored in. Static constant variables go in the text_section,
non-const variables go in the data_section, and non-static const
variables go in the const_section.
Since this macro is used in a number of places, we must also be able
to decide where to place string constants. */
{ \
if (TREE_CODE (T) == VAR_DECL) \
{ \
&& (DECL_INITIAL (T) == error_mark_node \
{ \
if (TREE_PUBLIC (T)) \
const_section (); \
else \
text_section (); \
} \
else \
data_section (); \
} \
if (*tree_code_type[(int) TREE_CODE (T)] == 'c') \
{ \
if ((TREE_CODE (T) == STRING_CST && flag_writable_strings)) \
data_section (); \
else \
text_section (); \
} \
/* This is used by a hook in varasm.c to write the assembler directives
that are needed to tell the startup code which constructors need to
be run. */
{ \
fprintf ((FILE),".globl $$PsectAttributes_NOOVR$$__gxx_init_1\n"); \
data_section(); \
fprintf ((FILE),"$$PsectAttributes_NOOVR$$__gxx_init_1:\n\t.long\t"); \
assemble_name ((FILE), (NAME)); \
fputc ('\n', (FILE)); \
/* This is used by a hook in varasm.c to write the assembler directives
that are needed to tell the startup code which destructors need to
be run. */
{ \
fprintf ((FILE),".globl $$PsectAttributes_NOOVR$$__gxx_clean_1\n"); \
data_section(); \
fprintf ((FILE),"$$PsectAttributes_NOOVR$$__gxx_clean_1:\n\t.long\t");\
assemble_name ((FILE), (NAME)); \
fputc ('\n', (FILE)); \
/* True for VMS V4.6 and later. */
/* The following definitions are used in libgcc2.c with the __main
function. The _SHR symbol is used when the sharable image library
for libg++ is used - this is picked up automatically by the linker
and this symbol points to the start of the __CTOR_LIST__ from libg++.
If libg++ is not being used, then __CTOR_LIST_SHR__ occurs just after
__CTOR_LIST__, and essentially points to the same list as __CTOR_LIST. */
#ifdef L__main
#define __CTOR_LIST__ __gxx_init_0
#define __CTOR_LIST_END__ __gxx_init_2
#define __CTOR_LIST_SHR__ $$PsectAttributes_NOSHR$$__gxx_init_0_shr
#define __CTOR_LIST_SHR_END__ $$PsectAttributes_NOSHR$$__gxx_init_2_shr
do { \
func_ptr *p; \
extern func_ptr __CTOR_LIST__[1], __CTOR_LIST_END__[1]; \
extern func_ptr __CTOR_LIST_SHR__[1], __CTOR_LIST_SHR_END__[1]; \
if (&__CTOR_LIST_SHR__[0] != &__CTOR_LIST__[1]) \
for (p = __CTOR_LIST_SHR__ + 1; p < __CTOR_LIST_SHR_END__ ; p++ ) \
if (*p) (*p) (); \
for (p = __CTOR_LIST__ + 1; p < __CTOR_LIST_END__ ; p++ ) \
if (*p) (*p) (); \
do { /* arrange for `return' from main() to pass through exit() */ \
__label__ foo; \
int *callers_caller_fp = (int *) __builtin_frame_address (3); \
register int retval asm ("r0"); \
callers_caller_fp[4] = (int) && foo; \
break; /* out of do-while block */ \
foo: \
exit (retval); \
} while (0); \
} while (0)
#define __DTOR_LIST__ __gxx_clean_0
#define __DTOR_LIST_END__ __gxx_clean_2
#define __DTOR_LIST_SHR__ $$PsectAttributes_NOSHR$$__gxx_clean_0_shr
#define __DTOR_LIST_SHR_END__ $$PsectAttributes_NOSHR$$__gxx_clean_2_shr
do { \
func_ptr *p; \
extern func_ptr __DTOR_LIST__[1], __DTOR_LIST_END__[1]; \
extern func_ptr __DTOR_LIST_SHR__[1], __DTOR_LIST_SHR_END__[1]; \
for (p = __DTOR_LIST__ + 1; p < __DTOR_LIST_END__ ; p++ ) \
if (*p) (*p) (); \
if (&__DTOR_LIST_SHR__[0] != &__DTOR_LIST__[1]) \
for (p = __DTOR_LIST_SHR__ + 1; p < __DTOR_LIST_SHR_END__ ; p++ ) \
if (*p) (*p) (); \
} while (0)
#endif /* L__main */