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d067e2aae0
From-SVN: r34294
2428 lines
70 KiB
C
2428 lines
70 KiB
C
/* Compute register class preferences for pseudo-registers.
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Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996
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1997, 1998, 1999, 2000 Free Software Foundation, Inc.
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This file is part of GNU CC.
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GNU CC is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GNU CC is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU CC; see the file COPYING. If not, write to
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the Free Software Foundation, 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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/* This file contains two passes of the compiler: reg_scan and reg_class.
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It also defines some tables of information about the hardware registers
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and a function init_reg_sets to initialize the tables. */
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#include "config.h"
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#include "system.h"
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#include "rtl.h"
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#include "tm_p.h"
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#include "hard-reg-set.h"
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#include "flags.h"
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#include "basic-block.h"
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#include "regs.h"
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#include "function.h"
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#include "insn-config.h"
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#include "recog.h"
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#include "reload.h"
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#include "real.h"
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#include "toplev.h"
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#include "output.h"
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#include "ggc.h"
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#ifndef REGISTER_MOVE_COST
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#define REGISTER_MOVE_COST(x, y) 2
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#endif
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static void init_reg_sets_1 PARAMS ((void));
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static void init_reg_modes PARAMS ((void));
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/* If we have auto-increment or auto-decrement and we can have secondary
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reloads, we are not allowed to use classes requiring secondary
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reloads for pseudos auto-incremented since reload can't handle it. */
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#ifdef AUTO_INC_DEC
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#if defined(SECONDARY_INPUT_RELOAD_CLASS) || defined(SECONDARY_OUTPUT_RELOAD_CLASS)
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#define FORBIDDEN_INC_DEC_CLASSES
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#endif
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#endif
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/* Register tables used by many passes. */
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/* Indexed by hard register number, contains 1 for registers
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that are fixed use (stack pointer, pc, frame pointer, etc.).
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These are the registers that cannot be used to allocate
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a pseudo reg for general use. */
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char fixed_regs[FIRST_PSEUDO_REGISTER];
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/* Same info as a HARD_REG_SET. */
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HARD_REG_SET fixed_reg_set;
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/* Data for initializing the above. */
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static char initial_fixed_regs[] = FIXED_REGISTERS;
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/* Indexed by hard register number, contains 1 for registers
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that are fixed use or are clobbered by function calls.
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These are the registers that cannot be used to allocate
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a pseudo reg whose life crosses calls unless we are able
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to save/restore them across the calls. */
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char call_used_regs[FIRST_PSEUDO_REGISTER];
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/* Same info as a HARD_REG_SET. */
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HARD_REG_SET call_used_reg_set;
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/* HARD_REG_SET of registers we want to avoid caller saving. */
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HARD_REG_SET losing_caller_save_reg_set;
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/* Data for initializing the above. */
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static char initial_call_used_regs[] = CALL_USED_REGISTERS;
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/* Indexed by hard register number, contains 1 for registers that are
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fixed use or call used registers that cannot hold quantities across
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calls even if we are willing to save and restore them. call fixed
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registers are a subset of call used registers. */
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char call_fixed_regs[FIRST_PSEUDO_REGISTER];
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/* The same info as a HARD_REG_SET. */
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HARD_REG_SET call_fixed_reg_set;
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/* Number of non-fixed registers. */
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int n_non_fixed_regs;
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/* Indexed by hard register number, contains 1 for registers
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that are being used for global register decls.
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These must be exempt from ordinary flow analysis
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and are also considered fixed. */
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char global_regs[FIRST_PSEUDO_REGISTER];
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/* Table of register numbers in the order in which to try to use them. */
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#ifdef REG_ALLOC_ORDER
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int reg_alloc_order[FIRST_PSEUDO_REGISTER] = REG_ALLOC_ORDER;
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/* The inverse of reg_alloc_order. */
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int inv_reg_alloc_order[FIRST_PSEUDO_REGISTER];
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#endif
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/* For each reg class, a HARD_REG_SET saying which registers are in it. */
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HARD_REG_SET reg_class_contents[N_REG_CLASSES];
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/* The same information, but as an array of unsigned ints. We copy from
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these unsigned ints to the table above. We do this so the tm.h files
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do not have to be aware of the wordsize for machines with <= 64 regs. */
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#define N_REG_INTS \
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((FIRST_PSEUDO_REGISTER + (HOST_BITS_PER_INT - 1)) / HOST_BITS_PER_INT)
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static unsigned int_reg_class_contents[N_REG_CLASSES][N_REG_INTS]
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= REG_CLASS_CONTENTS;
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/* For each reg class, number of regs it contains. */
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unsigned int reg_class_size[N_REG_CLASSES];
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/* For each reg class, table listing all the containing classes. */
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enum reg_class reg_class_superclasses[N_REG_CLASSES][N_REG_CLASSES];
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/* For each reg class, table listing all the classes contained in it. */
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enum reg_class reg_class_subclasses[N_REG_CLASSES][N_REG_CLASSES];
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/* For each pair of reg classes,
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a largest reg class contained in their union. */
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enum reg_class reg_class_subunion[N_REG_CLASSES][N_REG_CLASSES];
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/* For each pair of reg classes,
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the smallest reg class containing their union. */
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enum reg_class reg_class_superunion[N_REG_CLASSES][N_REG_CLASSES];
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/* Array containing all of the register names. Unless
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DEBUG_REGISTER_NAMES is defined, use the copy in print-rtl.c. */
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#ifdef DEBUG_REGISTER_NAMES
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const char * reg_names[] = REGISTER_NAMES;
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#endif
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/* For each hard register, the widest mode object that it can contain.
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This will be a MODE_INT mode if the register can hold integers. Otherwise
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it will be a MODE_FLOAT or a MODE_CC mode, whichever is valid for the
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register. */
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enum machine_mode reg_raw_mode[FIRST_PSEUDO_REGISTER];
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/* Maximum cost of moving from a register in one class to a register in
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another class. Based on REGISTER_MOVE_COST. */
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static int move_cost[N_REG_CLASSES][N_REG_CLASSES];
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/* Similar, but here we don't have to move if the first index is a subset
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of the second so in that case the cost is zero. */
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static int may_move_in_cost[N_REG_CLASSES][N_REG_CLASSES];
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/* Similar, but here we don't have to move if the first index is a superset
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of the second so in that case the cost is zero. */
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static int may_move_out_cost[N_REG_CLASSES][N_REG_CLASSES];
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#ifdef FORBIDDEN_INC_DEC_CLASSES
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/* These are the classes that regs which are auto-incremented or decremented
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cannot be put in. */
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static int forbidden_inc_dec_class[N_REG_CLASSES];
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/* Indexed by n, is non-zero if (REG n) is used in an auto-inc or auto-dec
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context. */
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static char *in_inc_dec;
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#endif /* FORBIDDEN_INC_DEC_CLASSES */
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#ifdef CLASS_CANNOT_CHANGE_SIZE
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/* These are the classes containing only registers that can be used in
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a SUBREG expression that changes the size of the register. */
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static int class_can_change_size[N_REG_CLASSES];
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/* Registers, including pseudos, which change size. */
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static regset reg_changes_size;
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#endif /* CLASS_CANNOT_CHANGE_SIZE */
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#ifdef HAVE_SECONDARY_RELOADS
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/* Sample MEM values for use by memory_move_secondary_cost. */
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static rtx top_of_stack[MAX_MACHINE_MODE];
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#endif /* HAVE_SECONDARY_RELOADS */
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/* Linked list of reg_info structures allocated for reg_n_info array.
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Grouping all of the allocated structures together in one lump
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means only one call to bzero to clear them, rather than n smaller
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calls. */
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struct reg_info_data {
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struct reg_info_data *next; /* next set of reg_info structures */
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size_t min_index; /* minimum index # */
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size_t max_index; /* maximum index # */
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char used_p; /* non-zero if this has been used previously */
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reg_info data[1]; /* beginning of the reg_info data */
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};
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static struct reg_info_data *reg_info_head;
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/* No more global register variables may be declared; true once
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regclass has been initialized. */
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static int no_global_reg_vars = 0;
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/* Function called only once to initialize the above data on reg usage.
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Once this is done, various switches may override. */
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void
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init_reg_sets ()
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{
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register int i, j;
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/* First copy the register information from the initial int form into
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the regsets. */
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for (i = 0; i < N_REG_CLASSES; i++)
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{
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CLEAR_HARD_REG_SET (reg_class_contents[i]);
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for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
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if (int_reg_class_contents[i][j / HOST_BITS_PER_INT]
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& ((unsigned) 1 << (j % HOST_BITS_PER_INT)))
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SET_HARD_REG_BIT (reg_class_contents[i], j);
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}
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bcopy (initial_fixed_regs, fixed_regs, sizeof fixed_regs);
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bcopy (initial_call_used_regs, call_used_regs, sizeof call_used_regs);
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bzero (global_regs, sizeof global_regs);
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/* Do any additional initialization regsets may need */
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INIT_ONCE_REG_SET ();
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#ifdef REG_ALLOC_ORDER
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for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
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inv_reg_alloc_order[reg_alloc_order[i]] = i;
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#endif
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}
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/* After switches have been processed, which perhaps alter
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`fixed_regs' and `call_used_regs', convert them to HARD_REG_SETs. */
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static void
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init_reg_sets_1 ()
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{
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register unsigned int i, j;
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/* This macro allows the fixed or call-used registers
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and the register classes to depend on target flags. */
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#ifdef CONDITIONAL_REGISTER_USAGE
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CONDITIONAL_REGISTER_USAGE;
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#endif
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/* Compute number of hard regs in each class. */
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bzero ((char *) reg_class_size, sizeof reg_class_size);
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for (i = 0; i < N_REG_CLASSES; i++)
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for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
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if (TEST_HARD_REG_BIT (reg_class_contents[i], j))
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reg_class_size[i]++;
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/* Initialize the table of subunions.
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reg_class_subunion[I][J] gets the largest-numbered reg-class
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that is contained in the union of classes I and J. */
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for (i = 0; i < N_REG_CLASSES; i++)
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{
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for (j = 0; j < N_REG_CLASSES; j++)
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{
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#ifdef HARD_REG_SET
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register /* Declare it register if it's a scalar. */
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#endif
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HARD_REG_SET c;
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register int k;
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COPY_HARD_REG_SET (c, reg_class_contents[i]);
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IOR_HARD_REG_SET (c, reg_class_contents[j]);
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for (k = 0; k < N_REG_CLASSES; k++)
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{
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GO_IF_HARD_REG_SUBSET (reg_class_contents[k], c,
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subclass1);
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continue;
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subclass1:
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/* keep the largest subclass */ /* SPEE 900308 */
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GO_IF_HARD_REG_SUBSET (reg_class_contents[k],
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reg_class_contents[(int) reg_class_subunion[i][j]],
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subclass2);
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reg_class_subunion[i][j] = (enum reg_class) k;
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subclass2:
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;
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}
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}
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}
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/* Initialize the table of superunions.
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reg_class_superunion[I][J] gets the smallest-numbered reg-class
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containing the union of classes I and J. */
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for (i = 0; i < N_REG_CLASSES; i++)
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{
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for (j = 0; j < N_REG_CLASSES; j++)
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{
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#ifdef HARD_REG_SET
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register /* Declare it register if it's a scalar. */
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#endif
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HARD_REG_SET c;
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register int k;
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COPY_HARD_REG_SET (c, reg_class_contents[i]);
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IOR_HARD_REG_SET (c, reg_class_contents[j]);
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for (k = 0; k < N_REG_CLASSES; k++)
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GO_IF_HARD_REG_SUBSET (c, reg_class_contents[k], superclass);
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superclass:
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reg_class_superunion[i][j] = (enum reg_class) k;
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}
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}
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/* Initialize the tables of subclasses and superclasses of each reg class.
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First clear the whole table, then add the elements as they are found. */
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for (i = 0; i < N_REG_CLASSES; i++)
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{
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for (j = 0; j < N_REG_CLASSES; j++)
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{
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reg_class_superclasses[i][j] = LIM_REG_CLASSES;
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reg_class_subclasses[i][j] = LIM_REG_CLASSES;
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}
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}
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for (i = 0; i < N_REG_CLASSES; i++)
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{
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if (i == (int) NO_REGS)
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continue;
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for (j = i + 1; j < N_REG_CLASSES; j++)
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{
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enum reg_class *p;
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GO_IF_HARD_REG_SUBSET (reg_class_contents[i], reg_class_contents[j],
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subclass);
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continue;
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subclass:
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/* Reg class I is a subclass of J.
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Add J to the table of superclasses of I. */
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p = ®_class_superclasses[i][0];
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while (*p != LIM_REG_CLASSES) p++;
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*p = (enum reg_class) j;
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/* Add I to the table of superclasses of J. */
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p = ®_class_subclasses[j][0];
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while (*p != LIM_REG_CLASSES) p++;
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*p = (enum reg_class) i;
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}
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}
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/* Initialize "constant" tables. */
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CLEAR_HARD_REG_SET (fixed_reg_set);
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CLEAR_HARD_REG_SET (call_used_reg_set);
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CLEAR_HARD_REG_SET (call_fixed_reg_set);
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bcopy (fixed_regs, call_fixed_regs, sizeof call_fixed_regs);
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n_non_fixed_regs = 0;
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for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
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{
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if (fixed_regs[i])
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SET_HARD_REG_BIT (fixed_reg_set, i);
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else
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n_non_fixed_regs++;
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if (call_used_regs[i])
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SET_HARD_REG_BIT (call_used_reg_set, i);
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if (call_fixed_regs[i])
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SET_HARD_REG_BIT (call_fixed_reg_set, i);
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if (CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (i)))
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SET_HARD_REG_BIT (losing_caller_save_reg_set, i);
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}
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/* Initialize the move cost table. Find every subset of each class
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and take the maximum cost of moving any subset to any other. */
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for (i = 0; i < N_REG_CLASSES; i++)
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for (j = 0; j < N_REG_CLASSES; j++)
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{
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int cost = i == j ? 2 : REGISTER_MOVE_COST (i, j);
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enum reg_class *p1, *p2;
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for (p2 = ®_class_subclasses[j][0]; *p2 != LIM_REG_CLASSES; p2++)
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if (*p2 != i)
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cost = MAX (cost, REGISTER_MOVE_COST (i, *p2));
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for (p1 = ®_class_subclasses[i][0]; *p1 != LIM_REG_CLASSES; p1++)
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{
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if (*p1 != j)
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cost = MAX (cost, REGISTER_MOVE_COST (*p1, j));
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for (p2 = ®_class_subclasses[j][0];
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*p2 != LIM_REG_CLASSES; p2++)
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if (*p1 != *p2)
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cost = MAX (cost, REGISTER_MOVE_COST (*p1, *p2));
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}
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move_cost[i][j] = cost;
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if (reg_class_subset_p (i, j))
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may_move_in_cost[i][j] = 0;
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else
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may_move_in_cost[i][j] = cost;
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||
|
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if (reg_class_subset_p (j, i))
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may_move_out_cost[i][j] = 0;
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||
else
|
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may_move_out_cost[i][j] = cost;
|
||
}
|
||
|
||
#ifdef CLASS_CANNOT_CHANGE_SIZE
|
||
{
|
||
HARD_REG_SET c;
|
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COMPL_HARD_REG_SET (c, reg_class_contents[CLASS_CANNOT_CHANGE_SIZE]);
|
||
|
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for (i = 0; i < N_REG_CLASSES; i++)
|
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{
|
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GO_IF_HARD_REG_SUBSET (reg_class_contents[i], c, ok_class);
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class_can_change_size [i] = 0;
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continue;
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ok_class:
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class_can_change_size [i] = 1;
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||
}
|
||
}
|
||
#endif /* CLASS_CANNOT_CHANGE_SIZE */
|
||
}
|
||
|
||
/* Compute the table of register modes.
|
||
These values are used to record death information for individual registers
|
||
(as opposed to a multi-register mode). */
|
||
|
||
static void
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||
init_reg_modes ()
|
||
{
|
||
register int i;
|
||
|
||
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
|
||
{
|
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reg_raw_mode[i] = choose_hard_reg_mode (i, 1);
|
||
|
||
/* If we couldn't find a valid mode, just use the previous mode.
|
||
??? One situation in which we need to do this is on the mips where
|
||
HARD_REGNO_NREGS (fpreg, [SD]Fmode) returns 2. Ideally we'd like
|
||
to use DF mode for the even registers and VOIDmode for the odd
|
||
(for the cpu models where the odd ones are inaccessible). */
|
||
if (reg_raw_mode[i] == VOIDmode)
|
||
reg_raw_mode[i] = i == 0 ? word_mode : reg_raw_mode[i-1];
|
||
}
|
||
}
|
||
|
||
/* Finish initializing the register sets and
|
||
initialize the register modes. */
|
||
|
||
void
|
||
init_regs ()
|
||
{
|
||
/* This finishes what was started by init_reg_sets, but couldn't be done
|
||
until after register usage was specified. */
|
||
init_reg_sets_1 ();
|
||
|
||
init_reg_modes ();
|
||
|
||
#ifdef HAVE_SECONDARY_RELOADS
|
||
{
|
||
/* Make some fake stack-frame MEM references for use in
|
||
memory_move_secondary_cost. */
|
||
int i;
|
||
|
||
for (i = 0; i < MAX_MACHINE_MODE; i++)
|
||
top_of_stack[i] = gen_rtx_MEM (i, stack_pointer_rtx);
|
||
ggc_add_rtx_root (top_of_stack, MAX_MACHINE_MODE);
|
||
}
|
||
#endif
|
||
}
|
||
|
||
#ifdef HAVE_SECONDARY_RELOADS
|
||
|
||
/* Compute extra cost of moving registers to/from memory due to reloads.
|
||
Only needed if secondary reloads are required for memory moves. */
|
||
|
||
int
|
||
memory_move_secondary_cost (mode, class, in)
|
||
enum machine_mode mode;
|
||
enum reg_class class;
|
||
int in;
|
||
{
|
||
enum reg_class altclass;
|
||
int partial_cost = 0;
|
||
/* We need a memory reference to feed to SECONDARY... macros. */
|
||
/* mem may be unused even if the SECONDARY_ macros are defined. */
|
||
rtx mem ATTRIBUTE_UNUSED = top_of_stack[(int) mode];
|
||
|
||
|
||
if (in)
|
||
{
|
||
#ifdef SECONDARY_INPUT_RELOAD_CLASS
|
||
altclass = SECONDARY_INPUT_RELOAD_CLASS (class, mode, mem);
|
||
#else
|
||
altclass = NO_REGS;
|
||
#endif
|
||
}
|
||
else
|
||
{
|
||
#ifdef SECONDARY_OUTPUT_RELOAD_CLASS
|
||
altclass = SECONDARY_OUTPUT_RELOAD_CLASS (class, mode, mem);
|
||
#else
|
||
altclass = NO_REGS;
|
||
#endif
|
||
}
|
||
|
||
if (altclass == NO_REGS)
|
||
return 0;
|
||
|
||
if (in)
|
||
partial_cost = REGISTER_MOVE_COST (altclass, class);
|
||
else
|
||
partial_cost = REGISTER_MOVE_COST (class, altclass);
|
||
|
||
if (class == altclass)
|
||
/* This isn't simply a copy-to-temporary situation. Can't guess
|
||
what it is, so MEMORY_MOVE_COST really ought not to be calling
|
||
here in that case.
|
||
|
||
I'm tempted to put in an abort here, but returning this will
|
||
probably only give poor estimates, which is what we would've
|
||
had before this code anyways. */
|
||
return partial_cost;
|
||
|
||
/* Check if the secondary reload register will also need a
|
||
secondary reload. */
|
||
return memory_move_secondary_cost (mode, altclass, in) + partial_cost;
|
||
}
|
||
#endif
|
||
|
||
/* Return a machine mode that is legitimate for hard reg REGNO and large
|
||
enough to save nregs. If we can't find one, return VOIDmode. */
|
||
|
||
enum machine_mode
|
||
choose_hard_reg_mode (regno, nregs)
|
||
unsigned int regno ATTRIBUTE_UNUSED;
|
||
unsigned int nregs;
|
||
{
|
||
enum machine_mode found_mode = VOIDmode, mode;
|
||
|
||
/* We first look for the largest integer mode that can be validly
|
||
held in REGNO. If none, we look for the largest floating-point mode.
|
||
If we still didn't find a valid mode, try CCmode. */
|
||
|
||
for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
|
||
mode != VOIDmode;
|
||
mode = GET_MODE_WIDER_MODE (mode))
|
||
if (HARD_REGNO_NREGS (regno, mode) == nregs
|
||
&& HARD_REGNO_MODE_OK (regno, mode))
|
||
found_mode = mode;
|
||
|
||
if (found_mode != VOIDmode)
|
||
return found_mode;
|
||
|
||
for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
|
||
mode != VOIDmode;
|
||
mode = GET_MODE_WIDER_MODE (mode))
|
||
if (HARD_REGNO_NREGS (regno, mode) == nregs
|
||
&& HARD_REGNO_MODE_OK (regno, mode))
|
||
found_mode = mode;
|
||
|
||
if (found_mode != VOIDmode)
|
||
return found_mode;
|
||
|
||
if (HARD_REGNO_NREGS (regno, CCmode) == nregs
|
||
&& HARD_REGNO_MODE_OK (regno, CCmode))
|
||
return CCmode;
|
||
|
||
/* We can't find a mode valid for this register. */
|
||
return VOIDmode;
|
||
}
|
||
|
||
/* Specify the usage characteristics of the register named NAME.
|
||
It should be a fixed register if FIXED and a
|
||
call-used register if CALL_USED. */
|
||
|
||
void
|
||
fix_register (name, fixed, call_used)
|
||
const char *name;
|
||
int fixed, call_used;
|
||
{
|
||
int i;
|
||
|
||
/* Decode the name and update the primary form of
|
||
the register info. */
|
||
|
||
if ((i = decode_reg_name (name)) >= 0)
|
||
{
|
||
if ((i == STACK_POINTER_REGNUM
|
||
#ifdef HARD_FRAME_POINTER_REGNUM
|
||
|| i == HARD_FRAME_POINTER_REGNUM
|
||
#else
|
||
|| i == FRAME_POINTER_REGNUM
|
||
#endif
|
||
)
|
||
&& (fixed == 0 || call_used == 0))
|
||
{
|
||
static const char * const what_option[2][2] = {
|
||
{ "call-saved", "call-used" },
|
||
{ "no-such-option", "fixed" }};
|
||
|
||
error ("can't use '%s' as a %s register", name,
|
||
what_option[fixed][call_used]);
|
||
}
|
||
else
|
||
{
|
||
fixed_regs[i] = fixed;
|
||
call_used_regs[i] = call_used;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
warning ("unknown register name: %s", name);
|
||
}
|
||
}
|
||
|
||
/* Mark register number I as global. */
|
||
|
||
void
|
||
globalize_reg (i)
|
||
int i;
|
||
{
|
||
if (fixed_regs[i] == 0 && no_global_reg_vars)
|
||
error ("global register variable follows a function definition");
|
||
|
||
if (global_regs[i])
|
||
{
|
||
warning ("register used for two global register variables");
|
||
return;
|
||
}
|
||
|
||
if (call_used_regs[i] && ! fixed_regs[i])
|
||
warning ("call-clobbered register used for global register variable");
|
||
|
||
global_regs[i] = 1;
|
||
|
||
/* If already fixed, nothing else to do. */
|
||
if (fixed_regs[i])
|
||
return;
|
||
|
||
fixed_regs[i] = call_used_regs[i] = call_fixed_regs[i] = 1;
|
||
n_non_fixed_regs--;
|
||
|
||
SET_HARD_REG_BIT (fixed_reg_set, i);
|
||
SET_HARD_REG_BIT (call_used_reg_set, i);
|
||
SET_HARD_REG_BIT (call_fixed_reg_set, i);
|
||
}
|
||
|
||
/* Now the data and code for the `regclass' pass, which happens
|
||
just before local-alloc. */
|
||
|
||
/* The `costs' struct records the cost of using a hard register of each class
|
||
and of using memory for each pseudo. We use this data to set up
|
||
register class preferences. */
|
||
|
||
struct costs
|
||
{
|
||
int cost[N_REG_CLASSES];
|
||
int mem_cost;
|
||
};
|
||
|
||
/* Structure used to record preferrences of given pseudo. */
|
||
struct reg_pref
|
||
{
|
||
/* (enum reg_class) prefclass is the preferred class. */
|
||
char prefclass;
|
||
|
||
/* altclass is a register class that we should use for allocating
|
||
pseudo if no register in the preferred class is available.
|
||
If no register in this class is available, memory is preferred.
|
||
|
||
It might appear to be more general to have a bitmask of classes here,
|
||
but since it is recommended that there be a class corresponding to the
|
||
union of most major pair of classes, that generality is not required. */
|
||
char altclass;
|
||
};
|
||
|
||
/* Record the cost of each class for each pseudo. */
|
||
|
||
static struct costs *costs;
|
||
|
||
/* Initialized once, and used to initialize cost values for each insn. */
|
||
|
||
static struct costs init_cost;
|
||
|
||
/* Record preferrences of each pseudo.
|
||
This is available after `regclass' is run. */
|
||
|
||
static struct reg_pref *reg_pref;
|
||
|
||
/* Allocated buffers for reg_pref. */
|
||
|
||
static struct reg_pref *reg_pref_buffer;
|
||
|
||
/* Account for the fact that insns within a loop are executed very commonly,
|
||
but don't keep doing this as loops go too deep. */
|
||
|
||
static int loop_cost;
|
||
|
||
static rtx scan_one_insn PARAMS ((rtx, int));
|
||
static void record_operand_costs PARAMS ((rtx, struct costs *, struct reg_pref *));
|
||
static void dump_regclass PARAMS ((FILE *));
|
||
static void record_reg_classes PARAMS ((int, int, rtx *, enum machine_mode *,
|
||
const char **, rtx,
|
||
struct costs *, struct reg_pref *));
|
||
static int copy_cost PARAMS ((rtx, enum machine_mode,
|
||
enum reg_class, int));
|
||
static void record_address_regs PARAMS ((rtx, enum reg_class, int));
|
||
#ifdef FORBIDDEN_INC_DEC_CLASSES
|
||
static int auto_inc_dec_reg_p PARAMS ((rtx, enum machine_mode));
|
||
#endif
|
||
static void reg_scan_mark_refs PARAMS ((rtx, rtx, int, unsigned int));
|
||
|
||
/* Return the reg_class in which pseudo reg number REGNO is best allocated.
|
||
This function is sometimes called before the info has been computed.
|
||
When that happens, just return GENERAL_REGS, which is innocuous. */
|
||
|
||
enum reg_class
|
||
reg_preferred_class (regno)
|
||
int regno;
|
||
{
|
||
if (reg_pref == 0)
|
||
return GENERAL_REGS;
|
||
return (enum reg_class) reg_pref[regno].prefclass;
|
||
}
|
||
|
||
enum reg_class
|
||
reg_alternate_class (regno)
|
||
int regno;
|
||
{
|
||
if (reg_pref == 0)
|
||
return ALL_REGS;
|
||
|
||
return (enum reg_class) reg_pref[regno].altclass;
|
||
}
|
||
|
||
/* Initialize some global data for this pass. */
|
||
|
||
void
|
||
regclass_init ()
|
||
{
|
||
int i;
|
||
|
||
init_cost.mem_cost = 10000;
|
||
for (i = 0; i < N_REG_CLASSES; i++)
|
||
init_cost.cost[i] = 10000;
|
||
|
||
/* This prevents dump_flow_info from losing if called
|
||
before regclass is run. */
|
||
reg_pref = NULL;
|
||
|
||
/* No more global register variables may be declared. */
|
||
no_global_reg_vars = 1;
|
||
}
|
||
|
||
/* Dump register costs. */
|
||
static void
|
||
dump_regclass (dump)
|
||
FILE *dump;
|
||
{
|
||
static const char *const reg_class_names[] = REG_CLASS_NAMES;
|
||
int i;
|
||
for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
|
||
{
|
||
enum reg_class class;
|
||
if (REG_N_REFS (i))
|
||
{
|
||
fprintf (dump, " Register %i costs:", i);
|
||
for (class = 0; class < N_REG_CLASSES; class++)
|
||
fprintf (dump, " %s:%i", reg_class_names[(int) class],
|
||
costs[i].cost[class]);
|
||
fprintf (dump, " MEM:%i\n", costs[i].mem_cost);
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
/* Calculate the costs of insn operands. */
|
||
|
||
static void
|
||
record_operand_costs (insn, op_costs, reg_pref)
|
||
rtx insn;
|
||
struct costs *op_costs;
|
||
struct reg_pref *reg_pref;
|
||
{
|
||
const char *constraints[MAX_RECOG_OPERANDS];
|
||
enum machine_mode modes[MAX_RECOG_OPERANDS];
|
||
int i;
|
||
|
||
for (i = 0; i < recog_data.n_operands; i++)
|
||
{
|
||
constraints[i] = recog_data.constraints[i];
|
||
modes[i] = recog_data.operand_mode[i];
|
||
}
|
||
|
||
/* If we get here, we are set up to record the costs of all the
|
||
operands for this insn. Start by initializing the costs.
|
||
Then handle any address registers. Finally record the desired
|
||
classes for any pseudos, doing it twice if some pair of
|
||
operands are commutative. */
|
||
|
||
for (i = 0; i < recog_data.n_operands; i++)
|
||
{
|
||
op_costs[i] = init_cost;
|
||
|
||
if (GET_CODE (recog_data.operand[i]) == SUBREG)
|
||
{
|
||
rtx inner = SUBREG_REG (recog_data.operand[i]);
|
||
#ifdef CLASS_CANNOT_CHANGE_SIZE
|
||
if (GET_MODE_SIZE (modes[i]) != GET_MODE_SIZE (GET_MODE (inner))
|
||
&& GET_CODE (inner) == REG)
|
||
SET_REGNO_REG_SET (reg_changes_size, REGNO (inner));
|
||
#endif
|
||
recog_data.operand[i] = inner;
|
||
}
|
||
|
||
if (GET_CODE (recog_data.operand[i]) == MEM)
|
||
record_address_regs (XEXP (recog_data.operand[i], 0),
|
||
BASE_REG_CLASS, loop_cost * 2);
|
||
else if (constraints[i][0] == 'p')
|
||
record_address_regs (recog_data.operand[i],
|
||
BASE_REG_CLASS, loop_cost * 2);
|
||
}
|
||
|
||
/* Check for commutative in a separate loop so everything will
|
||
have been initialized. We must do this even if one operand
|
||
is a constant--see addsi3 in m68k.md. */
|
||
|
||
for (i = 0; i < (int) recog_data.n_operands - 1; i++)
|
||
if (constraints[i][0] == '%')
|
||
{
|
||
const char *xconstraints[MAX_RECOG_OPERANDS];
|
||
int j;
|
||
|
||
/* Handle commutative operands by swapping the constraints.
|
||
We assume the modes are the same. */
|
||
|
||
for (j = 0; j < recog_data.n_operands; j++)
|
||
xconstraints[j] = constraints[j];
|
||
|
||
xconstraints[i] = constraints[i+1];
|
||
xconstraints[i+1] = constraints[i];
|
||
record_reg_classes (recog_data.n_alternatives, recog_data.n_operands,
|
||
recog_data.operand, modes,
|
||
xconstraints, insn, op_costs, reg_pref);
|
||
}
|
||
|
||
record_reg_classes (recog_data.n_alternatives, recog_data.n_operands,
|
||
recog_data.operand, modes,
|
||
constraints, insn, op_costs, reg_pref);
|
||
}
|
||
|
||
/* Subroutine of regclass, processes one insn INSN. Scan it and record each
|
||
time it would save code to put a certain register in a certain class.
|
||
PASS, when nonzero, inhibits some optimizations which need only be done
|
||
once.
|
||
Return the last insn processed, so that the scan can be continued from
|
||
there. */
|
||
|
||
static rtx
|
||
scan_one_insn (insn, pass)
|
||
rtx insn;
|
||
int pass;
|
||
{
|
||
enum rtx_code code = GET_CODE (insn);
|
||
enum rtx_code pat_code;
|
||
rtx set, note;
|
||
int i, j;
|
||
struct costs op_costs[MAX_RECOG_OPERANDS];
|
||
|
||
if (GET_RTX_CLASS (code) != 'i')
|
||
return insn;
|
||
|
||
pat_code = GET_CODE (PATTERN (insn));
|
||
if (pat_code == USE
|
||
|| pat_code == CLOBBER
|
||
|| pat_code == ASM_INPUT
|
||
|| pat_code == ADDR_VEC
|
||
|| pat_code == ADDR_DIFF_VEC)
|
||
return insn;
|
||
|
||
set = single_set (insn);
|
||
extract_insn (insn);
|
||
|
||
/* If this insn loads a parameter from its stack slot, then
|
||
it represents a savings, rather than a cost, if the
|
||
parameter is stored in memory. Record this fact. */
|
||
|
||
if (set != 0 && GET_CODE (SET_DEST (set)) == REG
|
||
&& GET_CODE (SET_SRC (set)) == MEM
|
||
&& (note = find_reg_note (insn, REG_EQUIV,
|
||
NULL_RTX)) != 0
|
||
&& GET_CODE (XEXP (note, 0)) == MEM)
|
||
{
|
||
costs[REGNO (SET_DEST (set))].mem_cost
|
||
-= (MEMORY_MOVE_COST (GET_MODE (SET_DEST (set)),
|
||
GENERAL_REGS, 1)
|
||
* loop_cost);
|
||
record_address_regs (XEXP (SET_SRC (set), 0),
|
||
BASE_REG_CLASS, loop_cost * 2);
|
||
return insn;
|
||
}
|
||
|
||
/* Improve handling of two-address insns such as
|
||
(set X (ashift CONST Y)) where CONST must be made to
|
||
match X. Change it into two insns: (set X CONST)
|
||
(set X (ashift X Y)). If we left this for reloading, it
|
||
would probably get three insns because X and Y might go
|
||
in the same place. This prevents X and Y from receiving
|
||
the same hard reg.
|
||
|
||
We can only do this if the modes of operands 0 and 1
|
||
(which might not be the same) are tieable and we only need
|
||
do this during our first pass. */
|
||
|
||
if (pass == 0 && optimize
|
||
&& recog_data.n_operands >= 3
|
||
&& recog_data.constraints[1][0] == '0'
|
||
&& recog_data.constraints[1][1] == 0
|
||
&& CONSTANT_P (recog_data.operand[1])
|
||
&& ! rtx_equal_p (recog_data.operand[0], recog_data.operand[1])
|
||
&& ! rtx_equal_p (recog_data.operand[0], recog_data.operand[2])
|
||
&& GET_CODE (recog_data.operand[0]) == REG
|
||
&& MODES_TIEABLE_P (GET_MODE (recog_data.operand[0]),
|
||
recog_data.operand_mode[1]))
|
||
{
|
||
rtx previnsn = prev_real_insn (insn);
|
||
rtx dest
|
||
= gen_lowpart (recog_data.operand_mode[1],
|
||
recog_data.operand[0]);
|
||
rtx newinsn
|
||
= emit_insn_before (gen_move_insn (dest, recog_data.operand[1]), insn);
|
||
|
||
/* If this insn was the start of a basic block,
|
||
include the new insn in that block.
|
||
We need not check for code_label here;
|
||
while a basic block can start with a code_label,
|
||
INSN could not be at the beginning of that block. */
|
||
if (previnsn == 0 || GET_CODE (previnsn) == JUMP_INSN)
|
||
{
|
||
int b;
|
||
for (b = 0; b < n_basic_blocks; b++)
|
||
if (insn == BLOCK_HEAD (b))
|
||
BLOCK_HEAD (b) = newinsn;
|
||
}
|
||
|
||
/* This makes one more setting of new insns's dest. */
|
||
REG_N_SETS (REGNO (recog_data.operand[0]))++;
|
||
|
||
*recog_data.operand_loc[1] = recog_data.operand[0];
|
||
for (i = recog_data.n_dups - 1; i >= 0; i--)
|
||
if (recog_data.dup_num[i] == 1)
|
||
*recog_data.dup_loc[i] = recog_data.operand[0];
|
||
|
||
return PREV_INSN (newinsn);
|
||
}
|
||
|
||
record_operand_costs (insn, op_costs, reg_pref);
|
||
|
||
/* Now add the cost for each operand to the total costs for
|
||
its register. */
|
||
|
||
for (i = 0; i < recog_data.n_operands; i++)
|
||
if (GET_CODE (recog_data.operand[i]) == REG
|
||
&& REGNO (recog_data.operand[i]) >= FIRST_PSEUDO_REGISTER)
|
||
{
|
||
int regno = REGNO (recog_data.operand[i]);
|
||
struct costs *p = &costs[regno], *q = &op_costs[i];
|
||
|
||
p->mem_cost += q->mem_cost * loop_cost;
|
||
for (j = 0; j < N_REG_CLASSES; j++)
|
||
p->cost[j] += q->cost[j] * loop_cost;
|
||
}
|
||
|
||
return insn;
|
||
}
|
||
|
||
/* This is a pass of the compiler that scans all instructions
|
||
and calculates the preferred class for each pseudo-register.
|
||
This information can be accessed later by calling `reg_preferred_class'.
|
||
This pass comes just before local register allocation. */
|
||
|
||
void
|
||
regclass (f, nregs, dump)
|
||
rtx f;
|
||
int nregs;
|
||
FILE *dump;
|
||
{
|
||
register rtx insn;
|
||
register int i;
|
||
int pass;
|
||
|
||
init_recog ();
|
||
|
||
costs = (struct costs *) xmalloc (nregs * sizeof (struct costs));
|
||
|
||
#ifdef CLASS_CANNOT_CHANGE_SIZE
|
||
reg_changes_size = BITMAP_XMALLOC();
|
||
#endif
|
||
|
||
#ifdef FORBIDDEN_INC_DEC_CLASSES
|
||
|
||
in_inc_dec = (char *) xmalloc (nregs);
|
||
|
||
/* Initialize information about which register classes can be used for
|
||
pseudos that are auto-incremented or auto-decremented. It would
|
||
seem better to put this in init_reg_sets, but we need to be able
|
||
to allocate rtx, which we can't do that early. */
|
||
|
||
for (i = 0; i < N_REG_CLASSES; i++)
|
||
{
|
||
rtx r = gen_rtx_REG (VOIDmode, 0);
|
||
enum machine_mode m;
|
||
register int j;
|
||
|
||
for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
|
||
if (TEST_HARD_REG_BIT (reg_class_contents[i], j))
|
||
{
|
||
REGNO (r) = j;
|
||
|
||
for (m = VOIDmode; (int) m < (int) MAX_MACHINE_MODE;
|
||
m = (enum machine_mode) ((int) m + 1))
|
||
if (HARD_REGNO_MODE_OK (j, m))
|
||
{
|
||
PUT_MODE (r, m);
|
||
|
||
/* If a register is not directly suitable for an
|
||
auto-increment or decrement addressing mode and
|
||
requires secondary reloads, disallow its class from
|
||
being used in such addresses. */
|
||
|
||
if ((0
|
||
#ifdef SECONDARY_RELOAD_CLASS
|
||
|| (SECONDARY_RELOAD_CLASS (BASE_REG_CLASS, m, r)
|
||
!= NO_REGS)
|
||
#else
|
||
#ifdef SECONDARY_INPUT_RELOAD_CLASS
|
||
|| (SECONDARY_INPUT_RELOAD_CLASS (BASE_REG_CLASS, m, r)
|
||
!= NO_REGS)
|
||
#endif
|
||
#ifdef SECONDARY_OUTPUT_RELOAD_CLASS
|
||
|| (SECONDARY_OUTPUT_RELOAD_CLASS (BASE_REG_CLASS, m, r)
|
||
!= NO_REGS)
|
||
#endif
|
||
#endif
|
||
)
|
||
&& ! auto_inc_dec_reg_p (r, m))
|
||
forbidden_inc_dec_class[i] = 1;
|
||
}
|
||
}
|
||
}
|
||
#endif /* FORBIDDEN_INC_DEC_CLASSES */
|
||
|
||
/* Normally we scan the insns once and determine the best class to use for
|
||
each register. However, if -fexpensive_optimizations are on, we do so
|
||
twice, the second time using the tentative best classes to guide the
|
||
selection. */
|
||
|
||
for (pass = 0; pass <= flag_expensive_optimizations; pass++)
|
||
{
|
||
int index;
|
||
|
||
if (dump)
|
||
fprintf (dump, "\n\nPass %i\n\n",pass);
|
||
/* Zero out our accumulation of the cost of each class for each reg. */
|
||
|
||
bzero ((char *) costs, nregs * sizeof (struct costs));
|
||
|
||
#ifdef FORBIDDEN_INC_DEC_CLASSES
|
||
bzero (in_inc_dec, nregs);
|
||
#endif
|
||
|
||
/* Scan the instructions and record each time it would
|
||
save code to put a certain register in a certain class. */
|
||
|
||
if (!optimize)
|
||
{
|
||
loop_cost = 1;
|
||
for (insn = f; insn; insn = NEXT_INSN (insn))
|
||
insn = scan_one_insn (insn, pass);
|
||
}
|
||
else
|
||
for (index = 0; index < n_basic_blocks; index++)
|
||
{
|
||
basic_block bb = BASIC_BLOCK (index);
|
||
|
||
/* Show that an insn inside a loop is likely to be executed three
|
||
times more than insns outside a loop. This is much more
|
||
aggressive than the assumptions made elsewhere and is being
|
||
tried as an experiment. */
|
||
if (optimize_size)
|
||
loop_cost = 1;
|
||
else
|
||
loop_cost = 1 << (2 * MIN (bb->loop_depth, 5));
|
||
for (insn = bb->head; ; insn = NEXT_INSN (insn))
|
||
{
|
||
insn = scan_one_insn (insn, pass);
|
||
if (insn == bb->end)
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Now for each register look at how desirable each class is
|
||
and find which class is preferred. Store that in
|
||
`prefclass'. Record in `altclass' the largest register
|
||
class any of whose registers is better than memory. */
|
||
|
||
if (pass == 0)
|
||
reg_pref = reg_pref_buffer;
|
||
|
||
if (dump)
|
||
{
|
||
dump_regclass (dump);
|
||
fprintf (dump,"\n");
|
||
}
|
||
for (i = FIRST_PSEUDO_REGISTER; i < nregs; i++)
|
||
{
|
||
register int best_cost = (1 << (HOST_BITS_PER_INT - 2)) - 1;
|
||
enum reg_class best = ALL_REGS, alt = NO_REGS;
|
||
/* This is an enum reg_class, but we call it an int
|
||
to save lots of casts. */
|
||
register int class;
|
||
register struct costs *p = &costs[i];
|
||
|
||
/* In non-optimizing compilation REG_N_REFS is not initialized
|
||
yet. */
|
||
if (optimize && !REG_N_REFS (i))
|
||
continue;
|
||
|
||
for (class = (int) ALL_REGS - 1; class > 0; class--)
|
||
{
|
||
/* Ignore classes that are too small for this operand or
|
||
invalid for a operand that was auto-incremented. */
|
||
if (CLASS_MAX_NREGS (class, PSEUDO_REGNO_MODE (i))
|
||
> reg_class_size[class]
|
||
#ifdef FORBIDDEN_INC_DEC_CLASSES
|
||
|| (in_inc_dec[i] && forbidden_inc_dec_class[class])
|
||
#endif
|
||
#ifdef CLASS_CANNOT_CHANGE_SIZE
|
||
|| (REGNO_REG_SET_P (reg_changes_size, i)
|
||
&& ! class_can_change_size [class])
|
||
#endif
|
||
)
|
||
;
|
||
else if (p->cost[class] < best_cost)
|
||
{
|
||
best_cost = p->cost[class];
|
||
best = (enum reg_class) class;
|
||
}
|
||
else if (p->cost[class] == best_cost)
|
||
best = reg_class_subunion[(int)best][class];
|
||
}
|
||
|
||
/* Record the alternate register class; i.e., a class for which
|
||
every register in it is better than using memory. If adding a
|
||
class would make a smaller class (i.e., no union of just those
|
||
classes exists), skip that class. The major unions of classes
|
||
should be provided as a register class. Don't do this if we
|
||
will be doing it again later. */
|
||
|
||
if ((pass == 1 || dump) || ! flag_expensive_optimizations)
|
||
for (class = 0; class < N_REG_CLASSES; class++)
|
||
if (p->cost[class] < p->mem_cost
|
||
&& (reg_class_size[(int) reg_class_subunion[(int) alt][class]]
|
||
> reg_class_size[(int) alt])
|
||
#ifdef FORBIDDEN_INC_DEC_CLASSES
|
||
&& ! (in_inc_dec[i] && forbidden_inc_dec_class[class])
|
||
#endif
|
||
#ifdef CLASS_CANNOT_CHANGE_SIZE
|
||
&& ! (REGNO_REG_SET_P (reg_changes_size, i)
|
||
&& ! class_can_change_size [class])
|
||
#endif
|
||
)
|
||
alt = reg_class_subunion[(int) alt][class];
|
||
|
||
/* If we don't add any classes, nothing to try. */
|
||
if (alt == best)
|
||
alt = NO_REGS;
|
||
|
||
if (dump
|
||
&& (reg_pref[i].prefclass != (int) best
|
||
|| reg_pref[i].altclass != (int) alt))
|
||
{
|
||
static const char *const reg_class_names[] = REG_CLASS_NAMES;
|
||
fprintf (dump, " Register %i", i);
|
||
if (alt == ALL_REGS || best == ALL_REGS)
|
||
fprintf (dump, " pref %s\n", reg_class_names[(int) best]);
|
||
else if (alt == NO_REGS)
|
||
fprintf (dump, " pref %s or none\n", reg_class_names[(int) best]);
|
||
else
|
||
fprintf (dump, " pref %s, else %s\n",
|
||
reg_class_names[(int) best],
|
||
reg_class_names[(int) alt]);
|
||
}
|
||
|
||
/* We cast to (int) because (char) hits bugs in some compilers. */
|
||
reg_pref[i].prefclass = (int) best;
|
||
reg_pref[i].altclass = (int) alt;
|
||
}
|
||
}
|
||
|
||
#ifdef FORBIDDEN_INC_DEC_CLASSES
|
||
free (in_inc_dec);
|
||
#endif
|
||
#ifdef CLASS_CANNOT_CHANGE_SIZE
|
||
BITMAP_XFREE (reg_changes_size);
|
||
#endif
|
||
free (costs);
|
||
}
|
||
|
||
/* Record the cost of using memory or registers of various classes for
|
||
the operands in INSN.
|
||
|
||
N_ALTS is the number of alternatives.
|
||
|
||
N_OPS is the number of operands.
|
||
|
||
OPS is an array of the operands.
|
||
|
||
MODES are the modes of the operands, in case any are VOIDmode.
|
||
|
||
CONSTRAINTS are the constraints to use for the operands. This array
|
||
is modified by this procedure.
|
||
|
||
This procedure works alternative by alternative. For each alternative
|
||
we assume that we will be able to allocate all pseudos to their ideal
|
||
register class and calculate the cost of using that alternative. Then
|
||
we compute for each operand that is a pseudo-register, the cost of
|
||
having the pseudo allocated to each register class and using it in that
|
||
alternative. To this cost is added the cost of the alternative.
|
||
|
||
The cost of each class for this insn is its lowest cost among all the
|
||
alternatives. */
|
||
|
||
static void
|
||
record_reg_classes (n_alts, n_ops, ops, modes,
|
||
constraints, insn, op_costs, reg_pref)
|
||
int n_alts;
|
||
int n_ops;
|
||
rtx *ops;
|
||
enum machine_mode *modes;
|
||
const char **constraints;
|
||
rtx insn;
|
||
struct costs *op_costs;
|
||
struct reg_pref *reg_pref;
|
||
{
|
||
int alt;
|
||
int i, j;
|
||
rtx set;
|
||
|
||
/* Process each alternative, each time minimizing an operand's cost with
|
||
the cost for each operand in that alternative. */
|
||
|
||
for (alt = 0; alt < n_alts; alt++)
|
||
{
|
||
struct costs this_op_costs[MAX_RECOG_OPERANDS];
|
||
int alt_fail = 0;
|
||
int alt_cost = 0;
|
||
enum reg_class classes[MAX_RECOG_OPERANDS];
|
||
int allows_mem[MAX_RECOG_OPERANDS];
|
||
int class;
|
||
|
||
for (i = 0; i < n_ops; i++)
|
||
{
|
||
const char *p = constraints[i];
|
||
rtx op = ops[i];
|
||
enum machine_mode mode = modes[i];
|
||
int allows_addr = 0;
|
||
int win = 0;
|
||
unsigned char c;
|
||
|
||
/* Initially show we know nothing about the register class. */
|
||
classes[i] = NO_REGS;
|
||
allows_mem[i] = 0;
|
||
|
||
/* If this operand has no constraints at all, we can conclude
|
||
nothing about it since anything is valid. */
|
||
|
||
if (*p == 0)
|
||
{
|
||
if (GET_CODE (op) == REG && REGNO (op) >= FIRST_PSEUDO_REGISTER)
|
||
bzero ((char *) &this_op_costs[i], sizeof this_op_costs[i]);
|
||
|
||
continue;
|
||
}
|
||
|
||
/* If this alternative is only relevant when this operand
|
||
matches a previous operand, we do different things depending
|
||
on whether this operand is a pseudo-reg or not. We must process
|
||
any modifiers for the operand before we can make this test. */
|
||
|
||
while (*p == '%' || *p == '=' || *p == '+' || *p == '&')
|
||
p++;
|
||
|
||
if (p[0] >= '0' && p[0] <= '0' + i && (p[1] == ',' || p[1] == 0))
|
||
{
|
||
/* Copy class and whether memory is allowed from the matching
|
||
alternative. Then perform any needed cost computations
|
||
and/or adjustments. */
|
||
j = p[0] - '0';
|
||
classes[i] = classes[j];
|
||
allows_mem[i] = allows_mem[j];
|
||
|
||
if (GET_CODE (op) != REG || REGNO (op) < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
/* If this matches the other operand, we have no added
|
||
cost and we win. */
|
||
if (rtx_equal_p (ops[j], op))
|
||
win = 1;
|
||
|
||
/* If we can put the other operand into a register, add to
|
||
the cost of this alternative the cost to copy this
|
||
operand to the register used for the other operand. */
|
||
|
||
else if (classes[j] != NO_REGS)
|
||
alt_cost += copy_cost (op, mode, classes[j], 1), win = 1;
|
||
}
|
||
else if (GET_CODE (ops[j]) != REG
|
||
|| REGNO (ops[j]) < FIRST_PSEUDO_REGISTER)
|
||
{
|
||
/* This op is a pseudo but the one it matches is not. */
|
||
|
||
/* If we can't put the other operand into a register, this
|
||
alternative can't be used. */
|
||
|
||
if (classes[j] == NO_REGS)
|
||
alt_fail = 1;
|
||
|
||
/* Otherwise, add to the cost of this alternative the cost
|
||
to copy the other operand to the register used for this
|
||
operand. */
|
||
|
||
else
|
||
alt_cost += copy_cost (ops[j], mode, classes[j], 1);
|
||
}
|
||
else
|
||
{
|
||
/* The costs of this operand are not the same as the other
|
||
operand since move costs are not symmetric. Moreover,
|
||
if we cannot tie them, this alternative needs to do a
|
||
copy, which is one instruction. */
|
||
|
||
struct costs *pp = &this_op_costs[i];
|
||
|
||
for (class = 0; class < N_REG_CLASSES; class++)
|
||
pp->cost[class]
|
||
= ((recog_data.operand_type[i] != OP_OUT
|
||
? may_move_in_cost[class][(int) classes[i]]
|
||
: 0)
|
||
+ (recog_data.operand_type[i] != OP_IN
|
||
? may_move_out_cost[(int) classes[i]][class]
|
||
: 0));
|
||
|
||
/* If the alternative actually allows memory, make things
|
||
a bit cheaper since we won't need an extra insn to
|
||
load it. */
|
||
|
||
pp->mem_cost
|
||
= ((recog_data.operand_type[i] != OP_IN
|
||
? MEMORY_MOVE_COST (mode, classes[i], 0)
|
||
: 0)
|
||
+ (recog_data.operand_type[i] != OP_OUT
|
||
? MEMORY_MOVE_COST (mode, classes[i], 1)
|
||
: 0) - allows_mem[i]);
|
||
|
||
/* If we have assigned a class to this register in our
|
||
first pass, add a cost to this alternative corresponding
|
||
to what we would add if this register were not in the
|
||
appropriate class. */
|
||
|
||
if (reg_pref)
|
||
alt_cost
|
||
+= (may_move_in_cost[(unsigned char) reg_pref[REGNO (op)].prefclass]
|
||
[(int) classes[i]]);
|
||
|
||
if (REGNO (ops[i]) != REGNO (ops[j])
|
||
&& ! find_reg_note (insn, REG_DEAD, op))
|
||
alt_cost += 2;
|
||
|
||
/* This is in place of ordinary cost computation
|
||
for this operand, so skip to the end of the
|
||
alternative (should be just one character). */
|
||
while (*p && *p++ != ',')
|
||
;
|
||
|
||
constraints[i] = p;
|
||
continue;
|
||
}
|
||
}
|
||
|
||
/* Scan all the constraint letters. See if the operand matches
|
||
any of the constraints. Collect the valid register classes
|
||
and see if this operand accepts memory. */
|
||
|
||
while (*p && (c = *p++) != ',')
|
||
switch (c)
|
||
{
|
||
case '*':
|
||
/* Ignore the next letter for this pass. */
|
||
p++;
|
||
break;
|
||
|
||
case '?':
|
||
alt_cost += 2;
|
||
case '!': case '#': case '&':
|
||
case '0': case '1': case '2': case '3': case '4':
|
||
case '5': case '6': case '7': case '8': case '9':
|
||
break;
|
||
|
||
case 'p':
|
||
allows_addr = 1;
|
||
win = address_operand (op, GET_MODE (op));
|
||
/* We know this operand is an address, so we want it to be
|
||
allocated to a register that can be the base of an
|
||
address, ie BASE_REG_CLASS. */
|
||
classes[i]
|
||
= reg_class_subunion[(int) classes[i]]
|
||
[(int) BASE_REG_CLASS];
|
||
break;
|
||
|
||
case 'm': case 'o': case 'V':
|
||
/* It doesn't seem worth distinguishing between offsettable
|
||
and non-offsettable addresses here. */
|
||
allows_mem[i] = 1;
|
||
if (GET_CODE (op) == MEM)
|
||
win = 1;
|
||
break;
|
||
|
||
case '<':
|
||
if (GET_CODE (op) == MEM
|
||
&& (GET_CODE (XEXP (op, 0)) == PRE_DEC
|
||
|| GET_CODE (XEXP (op, 0)) == POST_DEC))
|
||
win = 1;
|
||
break;
|
||
|
||
case '>':
|
||
if (GET_CODE (op) == MEM
|
||
&& (GET_CODE (XEXP (op, 0)) == PRE_INC
|
||
|| GET_CODE (XEXP (op, 0)) == POST_INC))
|
||
win = 1;
|
||
break;
|
||
|
||
case 'E':
|
||
#ifndef REAL_ARITHMETIC
|
||
/* Match any floating double constant, but only if
|
||
we can examine the bits of it reliably. */
|
||
if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
|
||
|| HOST_BITS_PER_WIDE_INT != BITS_PER_WORD)
|
||
&& GET_MODE (op) != VOIDmode && ! flag_pretend_float)
|
||
break;
|
||
#endif
|
||
if (GET_CODE (op) == CONST_DOUBLE)
|
||
win = 1;
|
||
break;
|
||
|
||
case 'F':
|
||
if (GET_CODE (op) == CONST_DOUBLE)
|
||
win = 1;
|
||
break;
|
||
|
||
case 'G':
|
||
case 'H':
|
||
if (GET_CODE (op) == CONST_DOUBLE
|
||
&& CONST_DOUBLE_OK_FOR_LETTER_P (op, c))
|
||
win = 1;
|
||
break;
|
||
|
||
case 's':
|
||
if (GET_CODE (op) == CONST_INT
|
||
|| (GET_CODE (op) == CONST_DOUBLE
|
||
&& GET_MODE (op) == VOIDmode))
|
||
break;
|
||
case 'i':
|
||
if (CONSTANT_P (op)
|
||
#ifdef LEGITIMATE_PIC_OPERAND_P
|
||
&& (! flag_pic || LEGITIMATE_PIC_OPERAND_P (op))
|
||
#endif
|
||
)
|
||
win = 1;
|
||
break;
|
||
|
||
case 'n':
|
||
if (GET_CODE (op) == CONST_INT
|
||
|| (GET_CODE (op) == CONST_DOUBLE
|
||
&& GET_MODE (op) == VOIDmode))
|
||
win = 1;
|
||
break;
|
||
|
||
case 'I':
|
||
case 'J':
|
||
case 'K':
|
||
case 'L':
|
||
case 'M':
|
||
case 'N':
|
||
case 'O':
|
||
case 'P':
|
||
if (GET_CODE (op) == CONST_INT
|
||
&& CONST_OK_FOR_LETTER_P (INTVAL (op), c))
|
||
win = 1;
|
||
break;
|
||
|
||
case 'X':
|
||
win = 1;
|
||
break;
|
||
|
||
#ifdef EXTRA_CONSTRAINT
|
||
case 'Q':
|
||
case 'R':
|
||
case 'S':
|
||
case 'T':
|
||
case 'U':
|
||
if (EXTRA_CONSTRAINT (op, c))
|
||
win = 1;
|
||
break;
|
||
#endif
|
||
|
||
case 'g':
|
||
if (GET_CODE (op) == MEM
|
||
|| (CONSTANT_P (op)
|
||
#ifdef LEGITIMATE_PIC_OPERAND_P
|
||
&& (! flag_pic || LEGITIMATE_PIC_OPERAND_P (op))
|
||
#endif
|
||
))
|
||
win = 1;
|
||
allows_mem[i] = 1;
|
||
case 'r':
|
||
classes[i]
|
||
= reg_class_subunion[(int) classes[i]][(int) GENERAL_REGS];
|
||
break;
|
||
|
||
default:
|
||
classes[i]
|
||
= reg_class_subunion[(int) classes[i]]
|
||
[(int) REG_CLASS_FROM_LETTER (c)];
|
||
}
|
||
|
||
constraints[i] = p;
|
||
|
||
/* How we account for this operand now depends on whether it is a
|
||
pseudo register or not. If it is, we first check if any
|
||
register classes are valid. If not, we ignore this alternative,
|
||
since we want to assume that all pseudos get allocated for
|
||
register preferencing. If some register class is valid, compute
|
||
the costs of moving the pseudo into that class. */
|
||
|
||
if (GET_CODE (op) == REG && REGNO (op) >= FIRST_PSEUDO_REGISTER)
|
||
{
|
||
if (classes[i] == NO_REGS)
|
||
{
|
||
/* We must always fail if the operand is a REG, but
|
||
we did not find a suitable class.
|
||
|
||
Otherwise we may perform an uninitialized read
|
||
from this_op_costs after the `continue' statement
|
||
below. */
|
||
alt_fail = 1;
|
||
}
|
||
else
|
||
{
|
||
struct costs *pp = &this_op_costs[i];
|
||
|
||
for (class = 0; class < N_REG_CLASSES; class++)
|
||
pp->cost[class]
|
||
= ((recog_data.operand_type[i] != OP_OUT
|
||
? may_move_in_cost[class][(int) classes[i]]
|
||
: 0)
|
||
+ (recog_data.operand_type[i] != OP_IN
|
||
? may_move_out_cost[(int) classes[i]][class]
|
||
: 0));
|
||
|
||
/* If the alternative actually allows memory, make things
|
||
a bit cheaper since we won't need an extra insn to
|
||
load it. */
|
||
|
||
pp->mem_cost
|
||
= ((recog_data.operand_type[i] != OP_IN
|
||
? MEMORY_MOVE_COST (mode, classes[i], 0)
|
||
: 0)
|
||
+ (recog_data.operand_type[i] != OP_OUT
|
||
? MEMORY_MOVE_COST (mode, classes[i], 1)
|
||
: 0) - allows_mem[i]);
|
||
|
||
/* If we have assigned a class to this register in our
|
||
first pass, add a cost to this alternative corresponding
|
||
to what we would add if this register were not in the
|
||
appropriate class. */
|
||
|
||
if (reg_pref)
|
||
alt_cost
|
||
+= (may_move_in_cost[(unsigned char) reg_pref[REGNO (op)].prefclass]
|
||
[(int) classes[i]]);
|
||
}
|
||
}
|
||
|
||
/* Otherwise, if this alternative wins, either because we
|
||
have already determined that or if we have a hard register of
|
||
the proper class, there is no cost for this alternative. */
|
||
|
||
else if (win
|
||
|| (GET_CODE (op) == REG
|
||
&& reg_fits_class_p (op, classes[i], 0, GET_MODE (op))))
|
||
;
|
||
|
||
/* If registers are valid, the cost of this alternative includes
|
||
copying the object to and/or from a register. */
|
||
|
||
else if (classes[i] != NO_REGS)
|
||
{
|
||
if (recog_data.operand_type[i] != OP_OUT)
|
||
alt_cost += copy_cost (op, mode, classes[i], 1);
|
||
|
||
if (recog_data.operand_type[i] != OP_IN)
|
||
alt_cost += copy_cost (op, mode, classes[i], 0);
|
||
}
|
||
|
||
/* The only other way this alternative can be used is if this is a
|
||
constant that could be placed into memory. */
|
||
|
||
else if (CONSTANT_P (op) && (allows_addr || allows_mem[i]))
|
||
alt_cost += MEMORY_MOVE_COST (mode, classes[i], 1);
|
||
else
|
||
alt_fail = 1;
|
||
}
|
||
|
||
if (alt_fail)
|
||
continue;
|
||
|
||
/* Finally, update the costs with the information we've calculated
|
||
about this alternative. */
|
||
|
||
for (i = 0; i < n_ops; i++)
|
||
if (GET_CODE (ops[i]) == REG
|
||
&& REGNO (ops[i]) >= FIRST_PSEUDO_REGISTER)
|
||
{
|
||
struct costs *pp = &op_costs[i], *qq = &this_op_costs[i];
|
||
int scale = 1 + (recog_data.operand_type[i] == OP_INOUT);
|
||
|
||
pp->mem_cost = MIN (pp->mem_cost,
|
||
(qq->mem_cost + alt_cost) * scale);
|
||
|
||
for (class = 0; class < N_REG_CLASSES; class++)
|
||
pp->cost[class] = MIN (pp->cost[class],
|
||
(qq->cost[class] + alt_cost) * scale);
|
||
}
|
||
}
|
||
|
||
/* If this insn is a single set copying operand 1 to operand 0
|
||
and one operand is a pseudo with the other a hard reg or a pseudo
|
||
that prefers a register that is in its own register class then
|
||
we may want to adjust the cost of that register class to -1.
|
||
|
||
Avoid the adjustment if the source does not die to avoid stressing of
|
||
register allocator by preferrencing two coliding registers into single
|
||
class.
|
||
|
||
Also avoid the adjustment if a copy between registers of the class
|
||
is expensive (ten times the cost of a default copy is considered
|
||
arbitrarily expensive). This avoids losing when the preferred class
|
||
is very expensive as the source of a copy instruction. */
|
||
|
||
if ((set = single_set (insn)) != 0
|
||
&& ops[0] == SET_DEST (set) && ops[1] == SET_SRC (set)
|
||
&& GET_CODE (ops[0]) == REG && GET_CODE (ops[1]) == REG
|
||
&& find_regno_note (insn, REG_DEAD, REGNO (ops[1])))
|
||
for (i = 0; i <= 1; i++)
|
||
if (REGNO (ops[i]) >= FIRST_PSEUDO_REGISTER)
|
||
{
|
||
unsigned int regno = REGNO (ops[!i]);
|
||
enum machine_mode mode = GET_MODE (ops[!i]);
|
||
int class;
|
||
unsigned int nr;
|
||
|
||
if (regno >= FIRST_PSEUDO_REGISTER && reg_pref != 0)
|
||
{
|
||
enum reg_class pref = reg_pref[regno].prefclass;
|
||
|
||
if ((reg_class_size[(unsigned char) pref]
|
||
== CLASS_MAX_NREGS (pref, mode))
|
||
&& REGISTER_MOVE_COST (pref, pref) < 10 * 2)
|
||
op_costs[i].cost[(unsigned char) pref] = -1;
|
||
}
|
||
else if (regno < FIRST_PSEUDO_REGISTER)
|
||
for (class = 0; class < N_REG_CLASSES; class++)
|
||
if (TEST_HARD_REG_BIT (reg_class_contents[class], regno)
|
||
&& reg_class_size[class] == CLASS_MAX_NREGS (class, mode))
|
||
{
|
||
if (reg_class_size[class] == 1)
|
||
op_costs[i].cost[class] = -1;
|
||
else
|
||
{
|
||
for (nr = 0; nr < HARD_REGNO_NREGS (regno, mode); nr++)
|
||
{
|
||
if (! TEST_HARD_REG_BIT (reg_class_contents[class],
|
||
regno + nr))
|
||
break;
|
||
}
|
||
|
||
if (nr == HARD_REGNO_NREGS (regno,mode))
|
||
op_costs[i].cost[class] = -1;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Compute the cost of loading X into (if TO_P is non-zero) or from (if
|
||
TO_P is zero) a register of class CLASS in mode MODE.
|
||
|
||
X must not be a pseudo. */
|
||
|
||
static int
|
||
copy_cost (x, mode, class, to_p)
|
||
rtx x;
|
||
enum machine_mode mode ATTRIBUTE_UNUSED;
|
||
enum reg_class class;
|
||
int to_p ATTRIBUTE_UNUSED;
|
||
{
|
||
#ifdef HAVE_SECONDARY_RELOADS
|
||
enum reg_class secondary_class = NO_REGS;
|
||
#endif
|
||
|
||
/* If X is a SCRATCH, there is actually nothing to move since we are
|
||
assuming optimal allocation. */
|
||
|
||
if (GET_CODE (x) == SCRATCH)
|
||
return 0;
|
||
|
||
/* Get the class we will actually use for a reload. */
|
||
class = PREFERRED_RELOAD_CLASS (x, class);
|
||
|
||
#ifdef HAVE_SECONDARY_RELOADS
|
||
/* If we need a secondary reload (we assume here that we are using
|
||
the secondary reload as an intermediate, not a scratch register), the
|
||
cost is that to load the input into the intermediate register, then
|
||
to copy them. We use a special value of TO_P to avoid recursion. */
|
||
|
||
#ifdef SECONDARY_INPUT_RELOAD_CLASS
|
||
if (to_p == 1)
|
||
secondary_class = SECONDARY_INPUT_RELOAD_CLASS (class, mode, x);
|
||
#endif
|
||
|
||
#ifdef SECONDARY_OUTPUT_RELOAD_CLASS
|
||
if (! to_p)
|
||
secondary_class = SECONDARY_OUTPUT_RELOAD_CLASS (class, mode, x);
|
||
#endif
|
||
|
||
if (secondary_class != NO_REGS)
|
||
return (move_cost[(int) secondary_class][(int) class]
|
||
+ copy_cost (x, mode, secondary_class, 2));
|
||
#endif /* HAVE_SECONDARY_RELOADS */
|
||
|
||
/* For memory, use the memory move cost, for (hard) registers, use the
|
||
cost to move between the register classes, and use 2 for everything
|
||
else (constants). */
|
||
|
||
if (GET_CODE (x) == MEM || class == NO_REGS)
|
||
return MEMORY_MOVE_COST (mode, class, to_p);
|
||
|
||
else if (GET_CODE (x) == REG)
|
||
return move_cost[(int) REGNO_REG_CLASS (REGNO (x))][(int) class];
|
||
|
||
else
|
||
/* If this is a constant, we may eventually want to call rtx_cost here. */
|
||
return 2;
|
||
}
|
||
|
||
/* Record the pseudo registers we must reload into hard registers
|
||
in a subexpression of a memory address, X.
|
||
|
||
CLASS is the class that the register needs to be in and is either
|
||
BASE_REG_CLASS or INDEX_REG_CLASS.
|
||
|
||
SCALE is twice the amount to multiply the cost by (it is twice so we
|
||
can represent half-cost adjustments). */
|
||
|
||
static void
|
||
record_address_regs (x, class, scale)
|
||
rtx x;
|
||
enum reg_class class;
|
||
int scale;
|
||
{
|
||
register enum rtx_code code = GET_CODE (x);
|
||
|
||
switch (code)
|
||
{
|
||
case CONST_INT:
|
||
case CONST:
|
||
case CC0:
|
||
case PC:
|
||
case SYMBOL_REF:
|
||
case LABEL_REF:
|
||
return;
|
||
|
||
case PLUS:
|
||
/* When we have an address that is a sum,
|
||
we must determine whether registers are "base" or "index" regs.
|
||
If there is a sum of two registers, we must choose one to be
|
||
the "base". Luckily, we can use the REGNO_POINTER_FLAG
|
||
to make a good choice most of the time. We only need to do this
|
||
on machines that can have two registers in an address and where
|
||
the base and index register classes are different.
|
||
|
||
??? This code used to set REGNO_POINTER_FLAG in some cases, but
|
||
that seems bogus since it should only be set when we are sure
|
||
the register is being used as a pointer. */
|
||
|
||
{
|
||
rtx arg0 = XEXP (x, 0);
|
||
rtx arg1 = XEXP (x, 1);
|
||
register enum rtx_code code0 = GET_CODE (arg0);
|
||
register enum rtx_code code1 = GET_CODE (arg1);
|
||
|
||
/* Look inside subregs. */
|
||
if (code0 == SUBREG)
|
||
arg0 = SUBREG_REG (arg0), code0 = GET_CODE (arg0);
|
||
if (code1 == SUBREG)
|
||
arg1 = SUBREG_REG (arg1), code1 = GET_CODE (arg1);
|
||
|
||
/* If this machine only allows one register per address, it must
|
||
be in the first operand. */
|
||
|
||
if (MAX_REGS_PER_ADDRESS == 1)
|
||
record_address_regs (arg0, class, scale);
|
||
|
||
/* If index and base registers are the same on this machine, just
|
||
record registers in any non-constant operands. We assume here,
|
||
as well as in the tests below, that all addresses are in
|
||
canonical form. */
|
||
|
||
else if (INDEX_REG_CLASS == BASE_REG_CLASS)
|
||
{
|
||
record_address_regs (arg0, class, scale);
|
||
if (! CONSTANT_P (arg1))
|
||
record_address_regs (arg1, class, scale);
|
||
}
|
||
|
||
/* If the second operand is a constant integer, it doesn't change
|
||
what class the first operand must be. */
|
||
|
||
else if (code1 == CONST_INT || code1 == CONST_DOUBLE)
|
||
record_address_regs (arg0, class, scale);
|
||
|
||
/* If the second operand is a symbolic constant, the first operand
|
||
must be an index register. */
|
||
|
||
else if (code1 == SYMBOL_REF || code1 == CONST || code1 == LABEL_REF)
|
||
record_address_regs (arg0, INDEX_REG_CLASS, scale);
|
||
|
||
/* If both operands are registers but one is already a hard register
|
||
of index or base class, give the other the class that the hard
|
||
register is not. */
|
||
|
||
#ifdef REG_OK_FOR_BASE_P
|
||
else if (code0 == REG && code1 == REG
|
||
&& REGNO (arg0) < FIRST_PSEUDO_REGISTER
|
||
&& (REG_OK_FOR_BASE_P (arg0) || REG_OK_FOR_INDEX_P (arg0)))
|
||
record_address_regs (arg1,
|
||
REG_OK_FOR_BASE_P (arg0)
|
||
? INDEX_REG_CLASS : BASE_REG_CLASS,
|
||
scale);
|
||
else if (code0 == REG && code1 == REG
|
||
&& REGNO (arg1) < FIRST_PSEUDO_REGISTER
|
||
&& (REG_OK_FOR_BASE_P (arg1) || REG_OK_FOR_INDEX_P (arg1)))
|
||
record_address_regs (arg0,
|
||
REG_OK_FOR_BASE_P (arg1)
|
||
? INDEX_REG_CLASS : BASE_REG_CLASS,
|
||
scale);
|
||
#endif
|
||
|
||
/* If one operand is known to be a pointer, it must be the base
|
||
with the other operand the index. Likewise if the other operand
|
||
is a MULT. */
|
||
|
||
else if ((code0 == REG && REGNO_POINTER_FLAG (REGNO (arg0)))
|
||
|| code1 == MULT)
|
||
{
|
||
record_address_regs (arg0, BASE_REG_CLASS, scale);
|
||
record_address_regs (arg1, INDEX_REG_CLASS, scale);
|
||
}
|
||
else if ((code1 == REG && REGNO_POINTER_FLAG (REGNO (arg1)))
|
||
|| code0 == MULT)
|
||
{
|
||
record_address_regs (arg0, INDEX_REG_CLASS, scale);
|
||
record_address_regs (arg1, BASE_REG_CLASS, scale);
|
||
}
|
||
|
||
/* Otherwise, count equal chances that each might be a base
|
||
or index register. This case should be rare. */
|
||
|
||
else
|
||
{
|
||
record_address_regs (arg0, BASE_REG_CLASS, scale / 2);
|
||
record_address_regs (arg0, INDEX_REG_CLASS, scale / 2);
|
||
record_address_regs (arg1, BASE_REG_CLASS, scale / 2);
|
||
record_address_regs (arg1, INDEX_REG_CLASS, scale / 2);
|
||
}
|
||
}
|
||
break;
|
||
|
||
case POST_INC:
|
||
case PRE_INC:
|
||
case POST_DEC:
|
||
case PRE_DEC:
|
||
/* Double the importance of a pseudo register that is incremented
|
||
or decremented, since it would take two extra insns
|
||
if it ends up in the wrong place. If the operand is a pseudo,
|
||
show it is being used in an INC_DEC context. */
|
||
|
||
#ifdef FORBIDDEN_INC_DEC_CLASSES
|
||
if (GET_CODE (XEXP (x, 0)) == REG
|
||
&& REGNO (XEXP (x, 0)) >= FIRST_PSEUDO_REGISTER)
|
||
in_inc_dec[REGNO (XEXP (x, 0))] = 1;
|
||
#endif
|
||
|
||
record_address_regs (XEXP (x, 0), class, 2 * scale);
|
||
break;
|
||
|
||
case REG:
|
||
{
|
||
register struct costs *pp = &costs[REGNO (x)];
|
||
register int i;
|
||
|
||
pp->mem_cost += (MEMORY_MOVE_COST (Pmode, class, 1) * scale) / 2;
|
||
|
||
for (i = 0; i < N_REG_CLASSES; i++)
|
||
pp->cost[i] += (may_move_in_cost[i][(int) class] * scale) / 2;
|
||
}
|
||
break;
|
||
|
||
default:
|
||
{
|
||
register const char *fmt = GET_RTX_FORMAT (code);
|
||
register int i;
|
||
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
|
||
if (fmt[i] == 'e')
|
||
record_address_regs (XEXP (x, i), class, scale);
|
||
}
|
||
}
|
||
}
|
||
|
||
#ifdef FORBIDDEN_INC_DEC_CLASSES
|
||
|
||
/* Return 1 if REG is valid as an auto-increment memory reference
|
||
to an object of MODE. */
|
||
|
||
static int
|
||
auto_inc_dec_reg_p (reg, mode)
|
||
rtx reg;
|
||
enum machine_mode mode;
|
||
{
|
||
if (HAVE_POST_INCREMENT
|
||
&& memory_address_p (mode, gen_rtx_POST_INC (Pmode, reg)))
|
||
return 1;
|
||
|
||
if (HAVE_POST_DECREMENT
|
||
&& memory_address_p (mode, gen_rtx_POST_DEC (Pmode, reg)))
|
||
return 1;
|
||
|
||
if (HAVE_PRE_INCREMENT
|
||
&& memory_address_p (mode, gen_rtx_PRE_INC (Pmode, reg)))
|
||
return 1;
|
||
|
||
if (HAVE_PRE_DECREMENT
|
||
&& memory_address_p (mode, gen_rtx_PRE_DEC (Pmode, reg)))
|
||
return 1;
|
||
|
||
return 0;
|
||
}
|
||
#endif
|
||
|
||
static short *renumber;
|
||
static size_t regno_allocated;
|
||
static unsigned int reg_n_max;
|
||
|
||
/* Allocate enough space to hold NUM_REGS registers for the tables used for
|
||
reg_scan and flow_analysis that are indexed by the register number. If
|
||
NEW_P is non zero, initialize all of the registers, otherwise only
|
||
initialize the new registers allocated. The same table is kept from
|
||
function to function, only reallocating it when we need more room. If
|
||
RENUMBER_P is non zero, allocate the reg_renumber array also. */
|
||
|
||
void
|
||
allocate_reg_info (num_regs, new_p, renumber_p)
|
||
size_t num_regs;
|
||
int new_p;
|
||
int renumber_p;
|
||
{
|
||
size_t size_info;
|
||
size_t size_renumber;
|
||
size_t min = (new_p) ? 0 : reg_n_max;
|
||
struct reg_info_data *reg_data;
|
||
|
||
if (num_regs > regno_allocated)
|
||
{
|
||
size_t old_allocated = regno_allocated;
|
||
|
||
regno_allocated = num_regs + (num_regs / 20); /* add some slop space */
|
||
size_renumber = regno_allocated * sizeof (short);
|
||
|
||
if (!reg_n_info)
|
||
{
|
||
VARRAY_REG_INIT (reg_n_info, regno_allocated, "reg_n_info");
|
||
renumber = (short *) xmalloc (size_renumber);
|
||
reg_pref_buffer = (struct reg_pref *) xmalloc (regno_allocated
|
||
* sizeof (struct reg_pref));
|
||
}
|
||
|
||
else
|
||
{
|
||
VARRAY_GROW (reg_n_info, regno_allocated);
|
||
|
||
if (new_p) /* if we're zapping everything, no need to realloc */
|
||
{
|
||
free ((char *)renumber);
|
||
free ((char *)reg_pref);
|
||
renumber = (short *) xmalloc (size_renumber);
|
||
reg_pref_buffer = (struct reg_pref *) xmalloc (regno_allocated
|
||
* sizeof (struct reg_pref));
|
||
}
|
||
|
||
else
|
||
{
|
||
renumber = (short *) xrealloc ((char *)renumber, size_renumber);
|
||
reg_pref_buffer = (struct reg_pref *) xrealloc ((char *)reg_pref_buffer,
|
||
regno_allocated
|
||
* sizeof (struct reg_pref));
|
||
}
|
||
}
|
||
|
||
size_info = (regno_allocated - old_allocated) * sizeof (reg_info)
|
||
+ sizeof (struct reg_info_data) - sizeof (reg_info);
|
||
reg_data = (struct reg_info_data *) xcalloc (size_info, 1);
|
||
reg_data->min_index = old_allocated;
|
||
reg_data->max_index = regno_allocated - 1;
|
||
reg_data->next = reg_info_head;
|
||
reg_info_head = reg_data;
|
||
}
|
||
|
||
reg_n_max = num_regs;
|
||
if (min < num_regs)
|
||
{
|
||
/* Loop through each of the segments allocated for the actual
|
||
reg_info pages, and set up the pointers, zero the pages, etc. */
|
||
for (reg_data = reg_info_head;
|
||
reg_data && reg_data->max_index >= min;
|
||
reg_data = reg_data->next)
|
||
{
|
||
size_t min_index = reg_data->min_index;
|
||
size_t max_index = reg_data->max_index;
|
||
size_t max = MIN (max_index, num_regs);
|
||
size_t local_min = min - min_index;
|
||
size_t i;
|
||
|
||
if (reg_data->min_index > num_regs)
|
||
continue;
|
||
|
||
if (min < min_index)
|
||
local_min = 0;
|
||
if (!reg_data->used_p) /* page just allocated with calloc */
|
||
reg_data->used_p = 1; /* no need to zero */
|
||
else
|
||
bzero ((char *) ®_data->data[local_min],
|
||
sizeof (reg_info) * (max - min_index - local_min + 1));
|
||
|
||
for (i = min_index+local_min; i <= max; i++)
|
||
{
|
||
VARRAY_REG (reg_n_info, i) = ®_data->data[i-min_index];
|
||
REG_BASIC_BLOCK (i) = REG_BLOCK_UNKNOWN;
|
||
renumber[i] = -1;
|
||
reg_pref_buffer[i].prefclass = (char) NO_REGS;
|
||
reg_pref_buffer[i].altclass = (char) NO_REGS;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* If {pref,alt}class have already been allocated, update the pointers to
|
||
the newly realloced ones. */
|
||
if (reg_pref)
|
||
reg_pref = reg_pref_buffer;
|
||
|
||
if (renumber_p)
|
||
reg_renumber = renumber;
|
||
|
||
/* Tell the regset code about the new number of registers */
|
||
MAX_REGNO_REG_SET (num_regs, new_p, renumber_p);
|
||
}
|
||
|
||
/* Free up the space allocated by allocate_reg_info. */
|
||
void
|
||
free_reg_info ()
|
||
{
|
||
if (reg_n_info)
|
||
{
|
||
struct reg_info_data *reg_data;
|
||
struct reg_info_data *reg_next;
|
||
|
||
VARRAY_FREE (reg_n_info);
|
||
for (reg_data = reg_info_head; reg_data; reg_data = reg_next)
|
||
{
|
||
reg_next = reg_data->next;
|
||
free ((char *)reg_data);
|
||
}
|
||
|
||
free (reg_pref_buffer);
|
||
reg_pref_buffer = (struct reg_pref *)0;
|
||
reg_info_head = (struct reg_info_data *)0;
|
||
renumber = (short *)0;
|
||
}
|
||
regno_allocated = 0;
|
||
reg_n_max = 0;
|
||
}
|
||
|
||
/* This is the `regscan' pass of the compiler, run just before cse
|
||
and again just before loop.
|
||
|
||
It finds the first and last use of each pseudo-register
|
||
and records them in the vectors regno_first_uid, regno_last_uid
|
||
and counts the number of sets in the vector reg_n_sets.
|
||
|
||
REPEAT is nonzero the second time this is called. */
|
||
|
||
/* Maximum number of parallel sets and clobbers in any insn in this fn.
|
||
Always at least 3, since the combiner could put that many together
|
||
and we want this to remain correct for all the remaining passes. */
|
||
|
||
int max_parallel;
|
||
|
||
void
|
||
reg_scan (f, nregs, repeat)
|
||
rtx f;
|
||
unsigned int nregs;
|
||
int repeat ATTRIBUTE_UNUSED;
|
||
{
|
||
register rtx insn;
|
||
|
||
allocate_reg_info (nregs, TRUE, FALSE);
|
||
max_parallel = 3;
|
||
|
||
for (insn = f; insn; insn = NEXT_INSN (insn))
|
||
if (GET_CODE (insn) == INSN
|
||
|| GET_CODE (insn) == CALL_INSN
|
||
|| GET_CODE (insn) == JUMP_INSN)
|
||
{
|
||
if (GET_CODE (PATTERN (insn)) == PARALLEL
|
||
&& XVECLEN (PATTERN (insn), 0) > max_parallel)
|
||
max_parallel = XVECLEN (PATTERN (insn), 0);
|
||
reg_scan_mark_refs (PATTERN (insn), insn, 0, 0);
|
||
|
||
if (REG_NOTES (insn))
|
||
reg_scan_mark_refs (REG_NOTES (insn), insn, 1, 0);
|
||
}
|
||
}
|
||
|
||
/* Update 'regscan' information by looking at the insns
|
||
from FIRST to LAST. Some new REGs have been created,
|
||
and any REG with number greater than OLD_MAX_REGNO is
|
||
such a REG. We only update information for those. */
|
||
|
||
void
|
||
reg_scan_update (first, last, old_max_regno)
|
||
rtx first;
|
||
rtx last;
|
||
unsigned int old_max_regno;
|
||
{
|
||
register rtx insn;
|
||
|
||
allocate_reg_info (max_reg_num (), FALSE, FALSE);
|
||
|
||
for (insn = first; insn != last; insn = NEXT_INSN (insn))
|
||
if (GET_CODE (insn) == INSN
|
||
|| GET_CODE (insn) == CALL_INSN
|
||
|| GET_CODE (insn) == JUMP_INSN)
|
||
{
|
||
if (GET_CODE (PATTERN (insn)) == PARALLEL
|
||
&& XVECLEN (PATTERN (insn), 0) > max_parallel)
|
||
max_parallel = XVECLEN (PATTERN (insn), 0);
|
||
reg_scan_mark_refs (PATTERN (insn), insn, 0, old_max_regno);
|
||
|
||
if (REG_NOTES (insn))
|
||
reg_scan_mark_refs (REG_NOTES (insn), insn, 1, old_max_regno);
|
||
}
|
||
}
|
||
|
||
/* X is the expression to scan. INSN is the insn it appears in.
|
||
NOTE_FLAG is nonzero if X is from INSN's notes rather than its body.
|
||
We should only record information for REGs with numbers
|
||
greater than or equal to MIN_REGNO. */
|
||
|
||
static void
|
||
reg_scan_mark_refs (x, insn, note_flag, min_regno)
|
||
rtx x;
|
||
rtx insn;
|
||
int note_flag;
|
||
unsigned int min_regno;
|
||
{
|
||
register enum rtx_code code;
|
||
register rtx dest;
|
||
register rtx note;
|
||
|
||
code = GET_CODE (x);
|
||
switch (code)
|
||
{
|
||
case CONST:
|
||
case CONST_INT:
|
||
case CONST_DOUBLE:
|
||
case CC0:
|
||
case PC:
|
||
case SYMBOL_REF:
|
||
case LABEL_REF:
|
||
case ADDR_VEC:
|
||
case ADDR_DIFF_VEC:
|
||
return;
|
||
|
||
case REG:
|
||
{
|
||
unsigned int regno = REGNO (x);
|
||
|
||
if (regno >= min_regno)
|
||
{
|
||
REGNO_LAST_NOTE_UID (regno) = INSN_UID (insn);
|
||
if (!note_flag)
|
||
REGNO_LAST_UID (regno) = INSN_UID (insn);
|
||
if (REGNO_FIRST_UID (regno) == 0)
|
||
REGNO_FIRST_UID (regno) = INSN_UID (insn);
|
||
}
|
||
}
|
||
break;
|
||
|
||
case EXPR_LIST:
|
||
if (XEXP (x, 0))
|
||
reg_scan_mark_refs (XEXP (x, 0), insn, note_flag, min_regno);
|
||
if (XEXP (x, 1))
|
||
reg_scan_mark_refs (XEXP (x, 1), insn, note_flag, min_regno);
|
||
break;
|
||
|
||
case INSN_LIST:
|
||
if (XEXP (x, 1))
|
||
reg_scan_mark_refs (XEXP (x, 1), insn, note_flag, min_regno);
|
||
break;
|
||
|
||
case SET:
|
||
/* Count a set of the destination if it is a register. */
|
||
for (dest = SET_DEST (x);
|
||
GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
|
||
|| GET_CODE (dest) == ZERO_EXTEND;
|
||
dest = XEXP (dest, 0))
|
||
;
|
||
|
||
if (GET_CODE (dest) == REG
|
||
&& REGNO (dest) >= min_regno)
|
||
REG_N_SETS (REGNO (dest))++;
|
||
|
||
/* If this is setting a pseudo from another pseudo or the sum of a
|
||
pseudo and a constant integer and the other pseudo is known to be
|
||
a pointer, set the destination to be a pointer as well.
|
||
|
||
Likewise if it is setting the destination from an address or from a
|
||
value equivalent to an address or to the sum of an address and
|
||
something else.
|
||
|
||
But don't do any of this if the pseudo corresponds to a user
|
||
variable since it should have already been set as a pointer based
|
||
on the type. */
|
||
|
||
if (GET_CODE (SET_DEST (x)) == REG
|
||
&& REGNO (SET_DEST (x)) >= FIRST_PSEUDO_REGISTER
|
||
&& REGNO (SET_DEST (x)) >= min_regno
|
||
/* If the destination pseudo is set more than once, then other
|
||
sets might not be to a pointer value (consider access to a
|
||
union in two threads of control in the presense of global
|
||
optimizations). So only set REGNO_POINTER_FLAG on the destination
|
||
pseudo if this is the only set of that pseudo. */
|
||
&& REG_N_SETS (REGNO (SET_DEST (x))) == 1
|
||
&& ! REG_USERVAR_P (SET_DEST (x))
|
||
&& ! REGNO_POINTER_FLAG (REGNO (SET_DEST (x)))
|
||
&& ((GET_CODE (SET_SRC (x)) == REG
|
||
&& REGNO_POINTER_FLAG (REGNO (SET_SRC (x))))
|
||
|| ((GET_CODE (SET_SRC (x)) == PLUS
|
||
|| GET_CODE (SET_SRC (x)) == LO_SUM)
|
||
&& GET_CODE (XEXP (SET_SRC (x), 1)) == CONST_INT
|
||
&& GET_CODE (XEXP (SET_SRC (x), 0)) == REG
|
||
&& REGNO_POINTER_FLAG (REGNO (XEXP (SET_SRC (x), 0))))
|
||
|| GET_CODE (SET_SRC (x)) == CONST
|
||
|| GET_CODE (SET_SRC (x)) == SYMBOL_REF
|
||
|| GET_CODE (SET_SRC (x)) == LABEL_REF
|
||
|| (GET_CODE (SET_SRC (x)) == HIGH
|
||
&& (GET_CODE (XEXP (SET_SRC (x), 0)) == CONST
|
||
|| GET_CODE (XEXP (SET_SRC (x), 0)) == SYMBOL_REF
|
||
|| GET_CODE (XEXP (SET_SRC (x), 0)) == LABEL_REF))
|
||
|| ((GET_CODE (SET_SRC (x)) == PLUS
|
||
|| GET_CODE (SET_SRC (x)) == LO_SUM)
|
||
&& (GET_CODE (XEXP (SET_SRC (x), 1)) == CONST
|
||
|| GET_CODE (XEXP (SET_SRC (x), 1)) == SYMBOL_REF
|
||
|| GET_CODE (XEXP (SET_SRC (x), 1)) == LABEL_REF))
|
||
|| ((note = find_reg_note (insn, REG_EQUAL, 0)) != 0
|
||
&& (GET_CODE (XEXP (note, 0)) == CONST
|
||
|| GET_CODE (XEXP (note, 0)) == SYMBOL_REF
|
||
|| GET_CODE (XEXP (note, 0)) == LABEL_REF))))
|
||
REGNO_POINTER_FLAG (REGNO (SET_DEST (x))) = 1;
|
||
|
||
/* ... fall through ... */
|
||
|
||
default:
|
||
{
|
||
register const char *fmt = GET_RTX_FORMAT (code);
|
||
register int i;
|
||
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
|
||
{
|
||
if (fmt[i] == 'e')
|
||
reg_scan_mark_refs (XEXP (x, i), insn, note_flag, min_regno);
|
||
else if (fmt[i] == 'E' && XVEC (x, i) != 0)
|
||
{
|
||
register int j;
|
||
for (j = XVECLEN (x, i) - 1; j >= 0; j--)
|
||
reg_scan_mark_refs (XVECEXP (x, i, j), insn, note_flag, min_regno);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Return nonzero if C1 is a subset of C2, i.e., if every register in C1
|
||
is also in C2. */
|
||
|
||
int
|
||
reg_class_subset_p (c1, c2)
|
||
register enum reg_class c1;
|
||
register enum reg_class c2;
|
||
{
|
||
if (c1 == c2) return 1;
|
||
|
||
if (c2 == ALL_REGS)
|
||
win:
|
||
return 1;
|
||
GO_IF_HARD_REG_SUBSET (reg_class_contents[(int)c1],
|
||
reg_class_contents[(int)c2],
|
||
win);
|
||
return 0;
|
||
}
|
||
|
||
/* Return nonzero if there is a register that is in both C1 and C2. */
|
||
|
||
int
|
||
reg_classes_intersect_p (c1, c2)
|
||
register enum reg_class c1;
|
||
register enum reg_class c2;
|
||
{
|
||
#ifdef HARD_REG_SET
|
||
register
|
||
#endif
|
||
HARD_REG_SET c;
|
||
|
||
if (c1 == c2) return 1;
|
||
|
||
if (c1 == ALL_REGS || c2 == ALL_REGS)
|
||
return 1;
|
||
|
||
COPY_HARD_REG_SET (c, reg_class_contents[(int) c1]);
|
||
AND_HARD_REG_SET (c, reg_class_contents[(int) c2]);
|
||
|
||
GO_IF_HARD_REG_SUBSET (c, reg_class_contents[(int) NO_REGS], lose);
|
||
return 1;
|
||
|
||
lose:
|
||
return 0;
|
||
}
|
||
|
||
/* Release any memory allocated by register sets. */
|
||
|
||
void
|
||
regset_release_memory ()
|
||
{
|
||
bitmap_release_memory ();
|
||
}
|