pa.h

gcc-2.95.3 Linux下最常用的C编译器

   is pushed.

   Arguments passed in registers are either 1 or 2 words long.

   The caller must make a distinction between calls to explicitly named
   functions and calls through pointers to functions -- the conventions
   are different!  Calls through pointers to functions only use general
   registers for the first four argument words.

   Of course all this is different for the portable runtime model
   HP wants everyone to use for ELF.  Ugh.  Here's a quick description
   of how it's supposed to work.

   1) callee side remains unchanged.  It expects integer args to be
   in the integer registers, float args in the float registers and
   unnamed args in integer registers.

   2) caller side now depends on if the function being called has
   a prototype in scope (rather than if it's being called indirectly).

      2a) If there is a prototype in scope, then arguments are passed
      according to their type (ints in integer registers, floats in float
      registers, unnamed args in integer registers.

      2b) If there is no prototype in scope, then floating point arguments
      are passed in both integer and float registers.  egad.

  FYI: The portable parameter passing conventions are almost exactly like
  the standard parameter passing conventions on the RS6000.  That's why
  you'll see lots of similar code in rs6000.h.  */

#define FUNCTION_ARG_PADDING(MODE, TYPE) function_arg_padding ((MODE), (TYPE))

/* Do not expect to understand this without reading it several times.  I'm
   tempted to try and simply it, but I worry about breaking something.  */

#define FUNCTION_ARG(CUM, MODE, TYPE, NAMED)		      		\
  (4 >= ((CUM).words + FUNCTION_ARG_SIZE ((MODE), (TYPE)))		\
   ? (!TARGET_PORTABLE_RUNTIME || (TYPE) == 0				\
      || !FLOAT_MODE_P (MODE) || TARGET_SOFT_FLOAT			\
      || (CUM).nargs_prototype > 0)					\
      ? gen_rtx_REG ((MODE),						\
		 (FUNCTION_ARG_SIZE ((MODE), (TYPE)) > 1		\
		  ? (((!(CUM).indirect 					\
		       || TARGET_PORTABLE_RUNTIME)			\
		      && (MODE) == DFmode				\
		      && ! TARGET_SOFT_FLOAT)				\
		     ? ((CUM).words ? 38 : 34)				\
		     : ((CUM).words ? 23 : 25))				\
		  : (((!(CUM).indirect					\
		       || TARGET_PORTABLE_RUNTIME)			\
		      && (MODE) == SFmode				\
		      && ! TARGET_SOFT_FLOAT)				\
		     ? (32 + 2 * (CUM).words)				\
		     : (27 - (CUM).words - FUNCTION_ARG_SIZE ((MODE),	\
							      (TYPE))))))\
   /* We are calling a non-prototyped function with floating point	\
      arguments using the portable conventions.  */			\
   : gen_rtx_PARALLEL ((MODE),						\
	      gen_rtvec							\
	      (2,							\
	       gen_rtx_EXPR_LIST (VOIDmode,				\
			gen_rtx_REG ((MODE),				\
				 (FUNCTION_ARG_SIZE ((MODE), (TYPE)) > 1 \
				  ? ((CUM).words ? 38 : 34)		\
				  : (32 + 2 * (CUM).words))),		\
			const0_rtx),					\
	       gen_rtx_EXPR_LIST (VOIDmode,				\
			gen_rtx_REG ((MODE),				\
				 (FUNCTION_ARG_SIZE ((MODE), (TYPE)) > 1 \
				  ? ((CUM).words ? 23 : 25)		\
				  : (27 - (CUM).words -			\
				     FUNCTION_ARG_SIZE ((MODE),		\
							(TYPE))))),	\
			const0_rtx)))					\
  /* Pass this parameter in the stack.  */				\
  : 0)

/* For an arg passed partly in registers and partly in memory,
   this is the number of registers used.
   For args passed entirely in registers or entirely in memory, zero.  */

#define FUNCTION_ARG_PARTIAL_NREGS(CUM, MODE, TYPE, NAMED) 0

/* If defined, a C expression that gives the alignment boundary, in
   bits, of an argument with the specified mode and type.  If it is
   not defined,  `PARM_BOUNDARY' is used for all arguments.  */

#define FUNCTION_ARG_BOUNDARY(MODE, TYPE)				\
  (((TYPE) != 0)							\
	? (((int_size_in_bytes (TYPE)) + 3) / 4) * BITS_PER_WORD	\
	: ((GET_MODE_ALIGNMENT(MODE) <= PARM_BOUNDARY)			\
		? PARM_BOUNDARY						\
		: GET_MODE_ALIGNMENT(MODE)))

/* Arguments larger than eight bytes are passed by invisible reference */

#define FUNCTION_ARG_PASS_BY_REFERENCE(CUM, MODE, TYPE, NAMED)		\
  ((TYPE) && int_size_in_bytes (TYPE) > 8)
 
#define FUNCTION_ARG_CALLEE_COPIES(CUM, MODE, TYPE, NAMED) \
  ((TYPE) && int_size_in_bytes (TYPE) > 8)


extern struct rtx_def *hppa_compare_op0, *hppa_compare_op1;
extern enum cmp_type hppa_branch_type;

/* Output the label for a function definition.  */
#ifndef HP_FP_ARG_DESCRIPTOR_REVERSED
#define ASM_DOUBLE_ARG_DESCRIPTORS(FILE, ARG0, ARG1)	\
  do { fprintf (FILE, ",ARGW%d=FR", (ARG0));		\
       fprintf (FILE, ",ARGW%d=FU", (ARG1));} while (0)
#define DFMODE_RETURN_STRING ",RTNVAL=FU"
#define SFMODE_RETURN_STRING ",RTNVAL=FR"
#else
#define ASM_DOUBLE_ARG_DESCRIPTORS(FILE, ARG0, ARG1)	\
  do { fprintf (FILE, ",ARGW%d=FU", (ARG0));		\
       fprintf (FILE, ",ARGW%d=FR", (ARG1));} while (0)
#define DFMODE_RETURN_STRING ",RTNVAL=FR"
#define SFMODE_RETURN_STRING ",RTNVAL=FU"
#endif

#define ASM_OUTPUT_MI_THUNK(FILE, THUNK_FNDECL, DELTA, FUNCTION) \
{ char *target_name = XSTR (XEXP (DECL_RTL (FUNCTION), 0), 0); \
  STRIP_NAME_ENCODING (target_name, target_name); \
  output_function_prologue (FILE, 0); \
  if (VAL_14_BITS_P (DELTA)) \
    fprintf (FILE, "\tb %s\n\tldo %d(%%r26),%%r26\n", target_name, DELTA); \
  else \
    fprintf (FILE, "\taddil L%%%d,%%r26\n\tb %s\n\tldo R%%%d(%%r1),%%r26\n", \
	     DELTA, target_name, DELTA); \
  fprintf (FILE, "\n\t.EXIT\n\t.PROCEND\n"); \
}

/* NAME refers to the function's name.  If we are placing each function into
   its own section, we need to switch to the section for this function.  Note
   that the section name will have a "." prefix.  */
#define ASM_OUTPUT_FUNCTION_PREFIX(FILE, NAME) \
  {									\
    char *name;								\
    STRIP_NAME_ENCODING (name, NAME);					\
    if (!TARGET_PORTABLE_RUNTIME && TARGET_GAS && in_section == in_text) \
      fputs ("\t.NSUBSPA $CODE$,QUAD=0,ALIGN=8,ACCESS=44,CODE_ONLY\n", FILE); \
    else if (! TARGET_PORTABLE_RUNTIME && TARGET_GAS)			\
      fprintf (FILE,							\
	       "\t.SUBSPA .%s\n", name);				\
  }
    
#define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL) \
    do { tree fntype = TREE_TYPE (TREE_TYPE (DECL));			\
	 tree tree_type = TREE_TYPE (DECL);				\
	 tree parm;							\
	 int i;								\
	 if (TREE_PUBLIC (DECL) || TARGET_GAS)				\
	   { extern int current_function_varargs;			\
	     if (TREE_PUBLIC (DECL))					\
	       {							\
		 fputs ("\t.EXPORT ", FILE);				\
		 assemble_name (FILE, NAME);				\
		 fputs (",ENTRY,PRIV_LEV=3", FILE);			\
	       }							\
	     else							\
	       {							\
		 fputs ("\t.PARAM ", FILE);				\
		 assemble_name (FILE, NAME);				\
	       }							\
	     if (TARGET_PORTABLE_RUNTIME)				\
	       {							\
		 fputs (",ARGW0=NO,ARGW1=NO,ARGW2=NO,ARGW3=NO,", FILE);	\
		 fputs ("RTNVAL=NO\n", FILE);				\
		 break;							\
	       }							\
	     for (parm = DECL_ARGUMENTS (DECL), i = 0; parm && i < 4;	\
		  parm = TREE_CHAIN (parm))				\
	       {							\
		 if (TYPE_MODE (DECL_ARG_TYPE (parm)) == SFmode		\
		     && ! TARGET_SOFT_FLOAT)				\
		   fprintf (FILE, ",ARGW%d=FR", i++);			\
		 else if (TYPE_MODE (DECL_ARG_TYPE (parm)) == DFmode	\
			  && ! TARGET_SOFT_FLOAT)			\
		   {							\
		     if (i <= 2)					\
		       {						\
			 if (i == 1) i++;				\
			 ASM_DOUBLE_ARG_DESCRIPTORS (FILE, i++, i++);	\
		       }						\
		     else						\
		       break;						\
		   }							\
		 else							\
		   {							\
		     int arg_size =					\
		       FUNCTION_ARG_SIZE (TYPE_MODE (DECL_ARG_TYPE (parm)),\
					  DECL_ARG_TYPE (parm));	\
		     /* Passing structs by invisible reference uses	\
			one general register.  */			\
		     if (arg_size > 2					\
			 || TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))	\
		       arg_size = 1;					\
		     if (arg_size == 2 && i <= 2)			\
		       {						\
			 if (i == 1) i++;				\
			 fprintf (FILE, ",ARGW%d=GR", i++);		\
			 fprintf (FILE, ",ARGW%d=GR", i++);		\
		       }						\
		     else if (arg_size == 1)				\
		       fprintf (FILE, ",ARGW%d=GR", i++);		\
		     else						\
		       i += arg_size;					\
		   }							\
	       }							\
	     /* anonymous args */					\
	     if ((TYPE_ARG_TYPES (tree_type) != 0			\
		  && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (tree_type)))\
		      != void_type_node))				\
		 || current_function_varargs)				\
	       {							\
		 for (; i < 4; i++)					\
		   fprintf (FILE, ",ARGW%d=GR", i);			\
	       }							\
	     if (TYPE_MODE (fntype) == DFmode && ! TARGET_SOFT_FLOAT)	\
	       fputs (DFMODE_RETURN_STRING, FILE);			\
	     else if (TYPE_MODE (fntype) == SFmode && ! TARGET_SOFT_FLOAT) \
	       fputs (SFMODE_RETURN_STRING, FILE);			\
	     else if (fntype != void_type_node)				\
	       fputs (",RTNVAL=GR", FILE);				\
	     fputs ("\n", FILE);					\
	   }} while (0)

/* This macro generates the assembly code for function entry.
   FILE is a stdio stream to output the code to.
   SIZE is an int: how many units of temporary storage to allocate.
   Refer to the array `regs_ever_live' to determine which registers
   to save; `regs_ever_live[I]' is nonzero if register number I
   is ever used in the function.  This macro is responsible for
   knowing which registers should not be saved even if used.  */

/* On HP-PA, move-double insns between fpu and cpu need an 8-byte block
   of memory.  If any fpu reg is used in the function, we allocate
   such a block here, at the bottom of the frame, just in case it's needed.

   If this function is a leaf procedure, then we may choose not
   to do a "save" insn.  The decision about whether or not
   to do this is made in regclass.c.  */

#define FUNCTION_PROLOGUE(FILE, SIZE) \
  output_function_prologue (FILE, SIZE)

/* Output assembler code to FILE to increment profiler label # LABELNO
   for profiling a function entry.

   Because HPUX _mcount is so different, we actually emit the
   profiling code in function_prologue. This just stores LABELNO for
   that. */

#define PROFILE_BEFORE_PROLOGUE
#define FUNCTION_PROFILER(FILE, LABELNO) \
{ extern int hp_profile_labelno; hp_profile_labelno = (LABELNO);}

/* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
   the stack pointer does not matter.  The value is tested only in
   functions that have frame pointers.
   No definition is equivalent to always zero.  */

extern int may_call_alloca;
extern int current_function_pretend_args_size;

#define EXIT_IGNORE_STACK	\
 (get_frame_size () != 0	\
  || current_function_calls_alloca || current_function_outgoing_args_size)


/* This macro generates the assembly code for function exit,
   on machines that need it.  If FUNCTION_EPILOGUE is not defined
   then individual return instructions are generated for each
   return statement.  Args are same as for FUNCTION_PROLOGUE.

   The function epilogue should not depend on the current stack pointer!
   It should use the frame pointer only.  This is mandatory because
   of alloca; we also take advantage of it to omit stack adjustments
   before returning.  */

/* This declaration is needed due to traditional/ANSI
   incompatibilities which cannot be #ifdefed away
   because they occur inside of macros.  Sigh.  */
extern union tree_node *current_function_decl;

#define FUNCTION_EPILOGUE(FILE, SIZE)			\
  output_function_epilogue (FILE, SIZE)

/* Output assembler code for a block containing the constant parts
   of a trampoline, leaving space for the variable parts.\

   The trampoline sets the static chain pointer to STATIC_CHAIN_REGNUM
   and then branches to the specified routine.

   This code template is copied from text segment to stack location
   and then patched with INITIALIZE_TRAMPOLINE to contain
   valid values, and then entered as a subroutine.

   It is best to keep this as small as possible to avoid having to
   flush multiple lines in the cache.  */

#define TRAMPOLINE_TEMPLATE(FILE) \
  {							\
    fputs ("\tldw	36(%r22),%r21\n", FILE);	\
    fputs ("\tbb,>=,n	%r21,30,.+16\n", FILE);	\
    fputs ("\tdepi	0,31,2,%r21\n", FILE);		\
    fputs ("\tldw	4(%r21),%r19\n", FILE);	\
    fputs ("\tldw	0(%r21),%r21\n", FILE);	\
    fputs ("\tldsid	(%r21),%r1\n", FILE);	\
    fputs ("\tmtsp	%r1,%sr0\n", FILE);		\
    fputs ("\tbe	0(%sr0,%r21)\n", FILE);	\
    fputs ("\tldw	40(%r22),%r29\n", FILE);	\
    fputs ("\t.word	0\n", FILE);			\
    fputs ("\t.word	0\n", FILE);			\
  }

/* Length in units of the trampoline for entering a nested function.

   Flush the cache entries corresponding to the first and last addresses
   of the trampoline.  This is necessary as the trampoline may cross two
   cache lines.

   If the code part of the trampoline ever grows to > 32 bytes, then it
   will become necessary to hack on the cacheflush pattern in pa.md.  */

#define TRAMPOLINE_SIZE (11 * 4)

/* Emit RTL insns to initialize the variable parts of a trampoline.
   FNADDR is an RTX for the address of the function's pure code.
   CXT is an RTX for the static chain value for the function.

   Move the function address to the trampoline template at offset 12.
   Move the static chain value to trampoline template at offset 16.  */

#define INITIALIZE_TRAMPOLINE(TRAMP, FNADDR, CXT) \
{									\
  rtx start_addr, end_addr;						\
									\
  start_addr = memory_address (Pmode, plus_constant ((TRAMP), 36));	\
  emit_move_insn (gen_rtx_MEM (Pmode, start_addr), (FNADDR));		\
  start_addr = memory_address (Pmode, plus_constant ((TRAMP), 40));	\
  emit_move_insn (gen_rtx_MEM (Pmode, start_addr), (CXT));		\
  /* fdc and fic only use registers for the address to flush,		\
     they do not accept integer displacements.  */ 			\