ia64.c

linux下的gcc编译器

/* Definitions of target machine for GNU compiler.
   Copyright (C) 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
   Contributed by James E. Wilson <[e-mail]> and
   		  David Mosberger <[e-mail]>.

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
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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.  */

#include "config.h"
#include "system.h"
#include "rtl.h"
#include "tree.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "real.h"
#include "insn-config.h"
#include "conditions.h"
#include "output.h"
#include "insn-attr.h"
#include "flags.h"
#include "recog.h"
#include "expr.h"
#include "optabs.h"
#include "except.h"
#include "function.h"
#include "ggc.h"
#include "basic-block.h"
#include "toplev.h"
#include "sched-int.h"
#include "timevar.h"
#include "target.h"
#include "target-def.h"
#include "tm_p.h"
#include "langhooks.h"

/* This is used for communication between ASM_OUTPUT_LABEL and
   ASM_OUTPUT_LABELREF.  */
int ia64_asm_output_label = 0;

/* Define the information needed to generate branch and scc insns.  This is
   stored from the compare operation.  */
struct rtx_def * ia64_compare_op0;
struct rtx_def * ia64_compare_op1;

/* Register names for ia64_expand_prologue.  */
static const char * const ia64_reg_numbers[96] =
{ "r32", "r33", "r34", "r35", "r36", "r37", "r38", "r39",
  "r40", "r41", "r42", "r43", "r44", "r45", "r46", "r47",
  "r48", "r49", "r50", "r51", "r52", "r53", "r54", "r55",
  "r56", "r57", "r58", "r59", "r60", "r61", "r62", "r63",
  "r64", "r65", "r66", "r67", "r68", "r69", "r70", "r71",
  "r72", "r73", "r74", "r75", "r76", "r77", "r78", "r79",
  "r80", "r81", "r82", "r83", "r84", "r85", "r86", "r87",
  "r88", "r89", "r90", "r91", "r92", "r93", "r94", "r95",
  "r96", "r97", "r98", "r99", "r100","r101","r102","r103",
  "r104","r105","r106","r107","r108","r109","r110","r111",
  "r112","r113","r114","r115","r116","r117","r118","r119",
  "r120","r121","r122","r123","r124","r125","r126","r127"};

/* ??? These strings could be shared with REGISTER_NAMES.  */
static const char * const ia64_input_reg_names[8] =
{ "in0",  "in1",  "in2",  "in3",  "in4",  "in5",  "in6",  "in7" };

/* ??? These strings could be shared with REGISTER_NAMES.  */
static const char * const ia64_local_reg_names[80] =
{ "loc0", "loc1", "loc2", "loc3", "loc4", "loc5", "loc6", "loc7",
  "loc8", "loc9", "loc10","loc11","loc12","loc13","loc14","loc15",
  "loc16","loc17","loc18","loc19","loc20","loc21","loc22","loc23",
  "loc24","loc25","loc26","loc27","loc28","loc29","loc30","loc31",
  "loc32","loc33","loc34","loc35","loc36","loc37","loc38","loc39",
  "loc40","loc41","loc42","loc43","loc44","loc45","loc46","loc47",
  "loc48","loc49","loc50","loc51","loc52","loc53","loc54","loc55",
  "loc56","loc57","loc58","loc59","loc60","loc61","loc62","loc63",
  "loc64","loc65","loc66","loc67","loc68","loc69","loc70","loc71",
  "loc72","loc73","loc74","loc75","loc76","loc77","loc78","loc79" };

/* ??? These strings could be shared with REGISTER_NAMES.  */
static const char * const ia64_output_reg_names[8] =
{ "out0", "out1", "out2", "out3", "out4", "out5", "out6", "out7" };

/* String used with the -mfixed-range= option.  */
const char *ia64_fixed_range_string;

/* Determines whether we use adds, addl, or movl to generate our
   TLS immediate offsets.  */
int ia64_tls_size = 22;

/* String used with the -mtls-size= option.  */
const char *ia64_tls_size_string;

/* Determines whether we run our final scheduling pass or not.  We always
   avoid the normal second scheduling pass.  */
static int ia64_flag_schedule_insns2;

/* Variables which are this size or smaller are put in the sdata/sbss
   sections.  */

unsigned int ia64_section_threshold;

/* Structure to be filled in by ia64_compute_frame_size with register
   save masks and offsets for the current function.  */

struct ia64_frame_info
{
  HOST_WIDE_INT total_size;	/* size of the stack frame, not including
				   the caller's scratch area.  */
  HOST_WIDE_INT spill_cfa_off;	/* top of the reg spill area from the cfa.  */
  HOST_WIDE_INT spill_size;	/* size of the gr/br/fr spill area.  */
  HOST_WIDE_INT extra_spill_size;  /* size of spill area for others.  */
  HARD_REG_SET mask;		/* mask of saved registers.  */
  unsigned int gr_used_mask;	/* mask of registers in use as gr spill 
				   registers or long-term scratches.  */
  int n_spilled;		/* number of spilled registers.  */
  int reg_fp;			/* register for fp.  */
  int reg_save_b0;		/* save register for b0.  */
  int reg_save_pr;		/* save register for prs.  */
  int reg_save_ar_pfs;		/* save register for ar.pfs.  */
  int reg_save_ar_unat;		/* save register for ar.unat.  */
  int reg_save_ar_lc;		/* save register for ar.lc.  */
  int reg_save_gp;		/* save register for gp.  */
  int n_input_regs;		/* number of input registers used.  */
  int n_local_regs;		/* number of local registers used.  */
  int n_output_regs;		/* number of output registers used.  */
  int n_rotate_regs;		/* number of rotating registers used.  */

  char need_regstk;		/* true if a .regstk directive needed.  */
  char initialized;		/* true if the data is finalized.  */
};

/* Current frame information calculated by ia64_compute_frame_size.  */
static struct ia64_frame_info current_frame_info;

static rtx gen_tls_get_addr PARAMS ((void));
static rtx gen_thread_pointer PARAMS ((void));
static int find_gr_spill PARAMS ((int));
static int next_scratch_gr_reg PARAMS ((void));
static void mark_reg_gr_used_mask PARAMS ((rtx, void *));
static void ia64_compute_frame_size PARAMS ((HOST_WIDE_INT));
static void setup_spill_pointers PARAMS ((int, rtx, HOST_WIDE_INT));
static void finish_spill_pointers PARAMS ((void));
static rtx spill_restore_mem PARAMS ((rtx, HOST_WIDE_INT));
static void do_spill PARAMS ((rtx (*)(rtx, rtx, rtx), rtx, HOST_WIDE_INT, rtx));
static void do_restore PARAMS ((rtx (*)(rtx, rtx, rtx), rtx, HOST_WIDE_INT));
static rtx gen_movdi_x PARAMS ((rtx, rtx, rtx));
static rtx gen_fr_spill_x PARAMS ((rtx, rtx, rtx));
static rtx gen_fr_restore_x PARAMS ((rtx, rtx, rtx));

static enum machine_mode hfa_element_mode PARAMS ((tree, int));
static void fix_range PARAMS ((const char *));
static struct machine_function * ia64_init_machine_status PARAMS ((void));
static void emit_insn_group_barriers PARAMS ((FILE *, rtx));
static void emit_all_insn_group_barriers PARAMS ((FILE *, rtx));
static void emit_predicate_relation_info PARAMS ((void));
static bool ia64_in_small_data_p PARAMS ((tree));
static void ia64_encode_section_info PARAMS ((tree, int));
static const char *ia64_strip_name_encoding PARAMS ((const char *));
static void process_epilogue PARAMS ((void));
static int process_set PARAMS ((FILE *, rtx));

static rtx ia64_expand_fetch_and_op PARAMS ((optab, enum machine_mode,
					     tree, rtx));
static rtx ia64_expand_op_and_fetch PARAMS ((optab, enum machine_mode,
					     tree, rtx));
static rtx ia64_expand_compare_and_swap PARAMS ((enum machine_mode,
						 enum machine_mode,
						 int, tree, rtx));
static rtx ia64_expand_lock_test_and_set PARAMS ((enum machine_mode,
						  tree, rtx));
static rtx ia64_expand_lock_release PARAMS ((enum machine_mode, tree, rtx));
static bool ia64_assemble_integer PARAMS ((rtx, unsigned int, int));
static void ia64_output_function_prologue PARAMS ((FILE *, HOST_WIDE_INT));
static void ia64_output_function_epilogue PARAMS ((FILE *, HOST_WIDE_INT));
static void ia64_output_function_end_prologue PARAMS ((FILE *));

static int ia64_issue_rate PARAMS ((void));
static int ia64_adjust_cost PARAMS ((rtx, rtx, rtx, int));
static void ia64_sched_init PARAMS ((FILE *, int, int));
static void ia64_sched_finish PARAMS ((FILE *, int));
static int ia64_internal_sched_reorder PARAMS ((FILE *, int, rtx *,
						int *, int, int));
static int ia64_sched_reorder PARAMS ((FILE *, int, rtx *, int *, int));
static int ia64_sched_reorder2 PARAMS ((FILE *, int, rtx *, int *, int));
static int ia64_variable_issue PARAMS ((FILE *, int, rtx, int));

static void ia64_output_mi_thunk PARAMS ((FILE *, tree, HOST_WIDE_INT,
					  HOST_WIDE_INT, tree));

static void ia64_select_rtx_section PARAMS ((enum machine_mode, rtx,
					     unsigned HOST_WIDE_INT));
static void ia64_rwreloc_select_section PARAMS ((tree, int,
					         unsigned HOST_WIDE_INT))
     ATTRIBUTE_UNUSED;
static void ia64_rwreloc_unique_section PARAMS ((tree, int))
     ATTRIBUTE_UNUSED;
static void ia64_rwreloc_select_rtx_section PARAMS ((enum machine_mode, rtx,
					             unsigned HOST_WIDE_INT))
     ATTRIBUTE_UNUSED;
static unsigned int ia64_rwreloc_section_type_flags
     PARAMS ((tree, const char *, int))
     ATTRIBUTE_UNUSED;

static void ia64_hpux_add_extern_decl PARAMS ((const char *name))
     ATTRIBUTE_UNUSED;

/* Table of valid machine attributes.  */
static const struct attribute_spec ia64_attribute_table[] =
{
  /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
  { "syscall_linkage", 0, 0, false, true,  true,  NULL },
  { NULL,              0, 0, false, false, false, NULL }
};

/* Initialize the GCC target structure.  */
#undef TARGET_ATTRIBUTE_TABLE
#define TARGET_ATTRIBUTE_TABLE ia64_attribute_table

#undef TARGET_INIT_BUILTINS
#define TARGET_INIT_BUILTINS ia64_init_builtins

#undef TARGET_EXPAND_BUILTIN
#define TARGET_EXPAND_BUILTIN ia64_expand_builtin

#undef TARGET_ASM_BYTE_OP
#define TARGET_ASM_BYTE_OP "\tdata1\t"
#undef TARGET_ASM_ALIGNED_HI_OP
#define TARGET_ASM_ALIGNED_HI_OP "\tdata2\t"
#undef TARGET_ASM_ALIGNED_SI_OP
#define TARGET_ASM_ALIGNED_SI_OP "\tdata4\t"
#undef TARGET_ASM_ALIGNED_DI_OP
#define TARGET_ASM_ALIGNED_DI_OP "\tdata8\t"
#undef TARGET_ASM_UNALIGNED_HI_OP
#define TARGET_ASM_UNALIGNED_HI_OP "\tdata2.ua\t"
#undef TARGET_ASM_UNALIGNED_SI_OP
#define TARGET_ASM_UNALIGNED_SI_OP "\tdata4.ua\t"
#undef TARGET_ASM_UNALIGNED_DI_OP
#define TARGET_ASM_UNALIGNED_DI_OP "\tdata8.ua\t"
#undef TARGET_ASM_INTEGER
#define TARGET_ASM_INTEGER ia64_assemble_integer

#undef TARGET_ASM_FUNCTION_PROLOGUE
#define TARGET_ASM_FUNCTION_PROLOGUE ia64_output_function_prologue
#undef TARGET_ASM_FUNCTION_END_PROLOGUE
#define TARGET_ASM_FUNCTION_END_PROLOGUE ia64_output_function_end_prologue
#undef TARGET_ASM_FUNCTION_EPILOGUE
#define TARGET_ASM_FUNCTION_EPILOGUE ia64_output_function_epilogue

#undef TARGET_IN_SMALL_DATA_P
#define TARGET_IN_SMALL_DATA_P  ia64_in_small_data_p
#undef TARGET_ENCODE_SECTION_INFO
#define TARGET_ENCODE_SECTION_INFO ia64_encode_section_info
#undef TARGET_STRIP_NAME_ENCODING
#define TARGET_STRIP_NAME_ENCODING ia64_strip_name_encoding

#undef TARGET_SCHED_ADJUST_COST
#define TARGET_SCHED_ADJUST_COST ia64_adjust_cost
#undef TARGET_SCHED_ISSUE_RATE
#define TARGET_SCHED_ISSUE_RATE ia64_issue_rate
#undef TARGET_SCHED_VARIABLE_ISSUE
#define TARGET_SCHED_VARIABLE_ISSUE ia64_variable_issue
#undef TARGET_SCHED_INIT
#define TARGET_SCHED_INIT ia64_sched_init
#undef TARGET_SCHED_FINISH
#define TARGET_SCHED_FINISH ia64_sched_finish
#undef TARGET_SCHED_REORDER
#define TARGET_SCHED_REORDER ia64_sched_reorder
#undef TARGET_SCHED_REORDER2
#define TARGET_SCHED_REORDER2 ia64_sched_reorder2

#undef TARGET_ASM_OUTPUT_MI_THUNK
#define TARGET_ASM_OUTPUT_MI_THUNK ia64_output_mi_thunk
#undef TARGET_ASM_CAN_OUTPUT_MI_THUNK
#define TARGET_ASM_CAN_OUTPUT_MI_THUNK hook_bool_tree_hwi_hwi_tree_true

struct gcc_target targetm = TARGET_INITIALIZER;

/* Return 1 if OP is a valid operand for the MEM of a CALL insn.  */

int
call_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  if (mode != GET_MODE (op) && mode != VOIDmode)
    return 0;

  return (GET_CODE (op) == SYMBOL_REF || GET_CODE (op) == REG
	  || (GET_CODE (op) == SUBREG && GET_CODE (XEXP (op, 0)) == REG));
}

/* Return 1 if OP refers to a symbol in the sdata section.  */

int
sdata_symbolic_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  switch (GET_CODE (op))
    {
    case CONST:
      if (GET_CODE (XEXP (op, 0)) != PLUS
	  || GET_CODE (XEXP (XEXP (op, 0), 0)) != SYMBOL_REF)
	break;
      op = XEXP (XEXP (op, 0), 0);
      /* FALLTHRU */

    case SYMBOL_REF:
      if (CONSTANT_POOL_ADDRESS_P (op))
	return GET_MODE_SIZE (get_pool_mode (op)) <= ia64_section_threshold;
      else
	{
	  const char *str = XSTR (op, 0);
          return (str[0] == ENCODE_SECTION_INFO_CHAR && str[1] == 's');
	}

    default:
      break;
    }

  return 0;
}

/* Return 1 if OP refers to a symbol, and is appropriate for a GOT load.  */

int
got_symbolic_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  switch (GET_CODE (op))
    {
    case CONST:
      op = XEXP (op, 0);
      if (GET_CODE (op) != PLUS)
	return 0;
      if (GET_CODE (XEXP (op, 0)) != SYMBOL_REF)
	return 0;
      op = XEXP (op, 1);
      if (GET_CODE (op) != CONST_INT)
	return 0;

	return 1;

      /* Ok if we're not using GOT entries at all.  */
      if (TARGET_NO_PIC || TARGET_AUTO_PIC)
	return 1;

      /* "Ok" while emitting rtl, since otherwise we won't be provided
	 with the entire offset during emission, which makes it very
	 hard to split the offset into high and low parts.  */
      if (rtx_equal_function_value_matters)
	return 1;

      /* Force the low 14 bits of the constant to zero so that we do not
	 use up so many GOT entries.  */
      return (INTVAL (op) & 0x3fff) == 0;

    case SYMBOL_REF:
    case LABEL_REF:
      return 1;

    default:
      break;
    }
  return 0;
}

/* Return 1 if OP refers to a symbol.  */

int
symbolic_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  switch (GET_CODE (op))
    {
    case CONST:
    case SYMBOL_REF:
    case LABEL_REF:
      return 1;

    default:
      break;
    }
  return 0;
}

/* Return tls_model if OP refers to a TLS symbol.  */

int
tls_symbolic_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  const char *str;

  if (GET_CODE (op) != SYMBOL_REF)
    return 0;
  str = XSTR (op, 0);
  if (str[0] != ENCODE_SECTION_INFO_CHAR)
    return 0;
  switch (str[1])
    {
    case 'G':
      return TLS_MODEL_GLOBAL_DYNAMIC;
    case 'L':
      return TLS_MODEL_LOCAL_DYNAMIC;
    case 'i':
      return TLS_MODEL_INITIAL_EXEC;
    case 'l':
      return TLS_MODEL_LOCAL_EXEC;
    }
  return 0;
}


/* Return 1 if OP refers to a function.  */

int
function_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  if (GET_CODE (op) == SYMBOL_REF && SYMBOL_REF_FLAG (op))
    return 1;
  else
    return 0;
}

/* Return 1 if OP is setjmp or a similar function.  */

/* ??? This is an unsatisfying solution.  Should rethink.  */

int
setjmp_operand (op, mode)
     rtx op;
     enum machine_mode mode ATTRIBUTE_UNUSED;
{
  const char *name;
  int retval = 0;

  if (GET_CODE (op) != SYMBOL_REF)
    return 0;