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Diffstat (limited to 'contrib/gcc/loop.h')
| -rw-r--r-- | contrib/gcc/loop.h | 249 |
1 files changed, 0 insertions, 249 deletions
diff --git a/contrib/gcc/loop.h b/contrib/gcc/loop.h deleted file mode 100644 index e164428d861f..000000000000 --- a/contrib/gcc/loop.h +++ /dev/null @@ -1,249 +0,0 @@ -/* Loop optimization definitions for GNU C-Compiler - Copyright (C) 1991, 1995, 1998, 1999 Free Software Foundation, Inc. - -This file is part of GNU CC. - -GNU CC is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. - -GNU CC is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with GNU CC; see the file COPYING. If not, write to -the Free Software Foundation, 59 Temple Place - Suite 330, -Boston, MA 02111-1307, USA. */ - -#include "varray.h" - -/* Get the luid of an insn. Catch the error of trying to reference the LUID - of an insn added during loop, since these don't have LUIDs. */ - -#define INSN_LUID(INSN) \ - (INSN_UID (INSN) < max_uid_for_loop ? uid_luid[INSN_UID (INSN)] \ - : (abort (), -1)) - -/* A "basic induction variable" or biv is a pseudo reg that is set - (within this loop) only by incrementing or decrementing it. */ -/* A "general induction variable" or giv is a pseudo reg whose - value is a linear function of a biv. */ - -/* Bivs are recognized by `basic_induction_var'; - Givs by `general_induct_var'. */ - -/* An enum for the two different types of givs, those that are used - as memory addresses and those that are calculated into registers. */ -enum g_types { DEST_ADDR, DEST_REG }; - -/* A `struct induction' is created for every instruction that sets - an induction variable (either a biv or a giv). */ - -struct induction -{ - rtx insn; /* The insn that sets a biv or giv */ - rtx new_reg; /* New register, containing strength reduced - version of this giv. */ - rtx src_reg; /* Biv from which this giv is computed. - (If this is a biv, then this is the biv.) */ - enum g_types giv_type; /* Indicate whether DEST_ADDR or DEST_REG */ - rtx dest_reg; /* Destination register for insn: this is the - register which was the biv or giv. - For a biv, this equals src_reg. - For a DEST_ADDR type giv, this is 0. */ - rtx *location; /* Place in the insn where this giv occurs. - If GIV_TYPE is DEST_REG, this is 0. */ - /* For a biv, this is the place where add_val - was found. */ - enum machine_mode mode; /* The mode of this biv or giv */ - enum machine_mode mem_mode; /* For DEST_ADDR, mode of the memory object. */ - rtx mult_val; /* Multiplicative factor for src_reg. */ - rtx add_val; /* Additive constant for that product. */ - int benefit; /* Gain from eliminating this insn. */ - rtx final_value; /* If the giv is used outside the loop, and its - final value could be calculated, it is put - here, and the giv is made replaceable. Set - the giv to this value before the loop. */ - unsigned combined_with; /* The number of givs this giv has been - combined with. If nonzero, this giv - cannot combine with any other giv. */ - unsigned replaceable : 1; /* 1 if we can substitute the strength-reduced - variable for the original variable. - 0 means they must be kept separate and the - new one must be copied into the old pseudo - reg each time the old one is set. */ - unsigned not_replaceable : 1; /* Used to prevent duplicating work. This is - 1 if we know that the giv definitely can - not be made replaceable, in which case we - don't bother checking the variable again - even if further info is available. - Both this and the above can be zero. */ - unsigned ignore : 1; /* 1 prohibits further processing of giv */ - unsigned always_computable : 1;/* 1 if this value is computable every - iteration. */ - unsigned always_executed : 1; /* 1 if this set occurs each iteration. */ - unsigned maybe_multiple : 1; /* Only used for a biv and 1 if this biv - update may be done multiple times per - iteration. */ - unsigned cant_derive : 1; /* For giv's, 1 if this giv cannot derive - another giv. This occurs in many cases - where a giv's lifetime spans an update to - a biv. */ - unsigned maybe_dead : 1; /* 1 if this giv might be dead. In that case, - we won't use it to eliminate a biv, it - would probably lose. */ - unsigned auto_inc_opt : 1; /* 1 if this giv had its increment output next - to it to try to form an auto-inc address. */ - unsigned unrolled : 1; /* 1 if new register has been allocated and - initialized in unrolled loop. */ - unsigned shared : 1; - unsigned no_const_addval : 1; /* 1 if add_val does not contain a const. */ - int lifetime; /* Length of life of this giv */ - rtx derive_adjustment; /* If nonzero, is an adjustment to be - subtracted from add_val when this giv - derives another. This occurs when the - giv spans a biv update by incrementation. */ - struct induction *next_iv; /* For givs, links together all givs that are - based on the same biv. For bivs, links - together all biv entries that refer to the - same biv register. */ - struct induction *same; /* If this giv has been combined with another - giv, this points to the base giv. The base - giv will have COMBINED_WITH non-zero. */ - struct induction *derived_from;/* For a giv, if we decided to derive this - giv from another one. */ - HOST_WIDE_INT const_adjust; /* Used by loop unrolling, when an address giv - is split, and a constant is eliminated from - the address, the -constant is stored here - for later use. */ - int ix; /* Used by recombine_givs, as n index into - the stats array. */ - struct induction *same_insn; /* If there are multiple identical givs in - the same insn, then all but one have this - field set, and they all point to the giv - that doesn't have this field set. */ - rtx last_use; /* For a giv made from a biv increment, this is - a substitute for the lifetime information. */ -}; - -/* A `struct iv_class' is created for each biv. */ - -struct iv_class { - int regno; /* Pseudo reg which is the biv. */ - int biv_count; /* Number of insns setting this reg. */ - struct induction *biv; /* List of all insns that set this reg. */ - int giv_count; /* Number of DEST_REG givs computed from this - biv. The resulting count is only used in - check_dbra_loop. */ - struct induction *giv; /* List of all insns that compute a giv - from this reg. */ - int total_benefit; /* Sum of BENEFITs of all those givs */ - rtx initial_value; /* Value of reg at loop start */ - rtx initial_test; /* Test performed on BIV before loop */ - struct iv_class *next; /* Links all class structures together */ - rtx init_insn; /* insn which initializes biv, 0 if none. */ - rtx init_set; /* SET of INIT_INSN, if any. */ - unsigned incremented : 1; /* 1 if somewhere incremented/decremented */ - unsigned eliminable : 1; /* 1 if plausible candidate for elimination. */ - unsigned nonneg : 1; /* 1 if we added a REG_NONNEG note for this. */ - unsigned reversed : 1; /* 1 if we reversed the loop that this - biv controls. */ -}; - -/* Information required to calculate the number of loop iterations. - This is set by loop_iterations. */ - -struct loop_info -{ - /* Register or constant initial loop value. */ - rtx initial_value; - /* Register or constant value used for comparison test. */ - rtx comparison_value; - /* Register or constant approximate final value. */ - rtx final_value; - /* Register or constant initial loop value with term common to - final_value removed. */ - rtx initial_equiv_value; - /* Register or constant final loop value with term common to - initial_value removed. */ - rtx final_equiv_value; - /* Register corresponding to iteration variable. */ - rtx iteration_var; - /* Constant loop increment. */ - rtx increment; - enum rtx_code comparison_code; - /* Holds the number of loop iterations. It is zero if the number - could not be calculated. Must be unsigned since the number of - iterations can be as high as 2^wordsize - 1. For loops with a - wider iterator, this number will be zero if the number of loop - iterations is too large for an unsigned integer to hold. */ - unsigned HOST_WIDE_INT n_iterations; - /* The loop unrolling factor. - Potential values: - 0: unrolled - 1: not unrolled. - -1: completely unrolled - >0: holds the unroll exact factor. */ - unsigned int unroll_number; - /* Non-zero if the loop has a NOTE_INSN_LOOP_VTOP. */ - rtx vtop; -}; - -/* Definitions used by the basic induction variable discovery code. */ -enum iv_mode { UNKNOWN_INDUCT, BASIC_INDUCT, NOT_BASIC_INDUCT, - GENERAL_INDUCT }; - -/* Variables declared in loop.c, but also needed in unroll.c. */ - -extern int *uid_luid; -extern int max_uid_for_loop; -extern int *uid_loop_num; -extern int *loop_outer_loop; -extern rtx *loop_number_exit_labels; -extern int *loop_number_exit_count; -extern int max_reg_before_loop; - -extern FILE *loop_dump_stream; - -extern varray_type reg_iv_type; -extern varray_type reg_iv_info; - -#define REG_IV_TYPE(n) \ - (*(enum iv_mode *) &VARRAY_INT(reg_iv_type, (n))) -#define REG_IV_INFO(n) \ - (*(struct induction **) &VARRAY_GENERIC_PTR(reg_iv_info, (n))) - -extern struct iv_class **reg_biv_class; -extern struct iv_class *loop_iv_list; - -extern int first_increment_giv, last_increment_giv; - -/* Forward declarations for non-static functions declared in loop.c and - unroll.c. */ -int invariant_p PROTO((rtx)); -rtx get_condition_for_loop PROTO((rtx)); -void emit_iv_add_mult PROTO((rtx, rtx, rtx, rtx, rtx)); -rtx express_from PROTO((struct induction *, struct induction *)); - -void unroll_loop PROTO((rtx, int, rtx, rtx, struct loop_info *, int)); -rtx biv_total_increment PROTO((struct iv_class *, rtx, rtx)); -unsigned HOST_WIDE_INT loop_iterations PROTO((rtx, rtx, struct loop_info *)); -int precondition_loop_p PROTO((rtx, struct loop_info *, - rtx *, rtx *, rtx *, - enum machine_mode *mode)); -rtx final_biv_value PROTO((struct iv_class *, rtx, rtx, - unsigned HOST_WIDE_INT)); -rtx final_giv_value PROTO((struct induction *, rtx, rtx, - unsigned HOST_WIDE_INT)); -void emit_unrolled_add PROTO((rtx, rtx, rtx)); -int back_branch_in_range_p PROTO((rtx, rtx, rtx)); -int loop_insn_first_p PROTO((rtx, rtx)); - -extern int *loop_unroll_number; - -/* Forward declarations for non-static functions declared in stmt.c. */ -void find_loop_tree_blocks PROTO((void)); -void unroll_block_trees PROTO((void)); |