662 lines
26 KiB
C
662 lines
26 KiB
C
/* Instruction scheduling pass. This file contains definitions used
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internally in the scheduler.
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Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998,
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1999, 2000, 2001, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 2, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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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 GCC; see the file COPYING. If not, write to the Free
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Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301, USA. */
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#ifndef GCC_SCHED_INT_H
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#define GCC_SCHED_INT_H
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/* For state_t. */
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#include "insn-attr.h"
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/* For regset_head. */
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#include "basic-block.h"
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/* For reg_note. */
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#include "rtl.h"
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/* Pointer to data describing the current DFA state. */
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extern state_t curr_state;
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/* Forward declaration. */
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struct ready_list;
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/* Type to represent status of a dependence. */
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typedef int ds_t;
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/* Type to represent weakness of speculative dependence. */
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typedef int dw_t;
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/* Describe state of dependencies used during sched_analyze phase. */
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struct deps
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{
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/* The *_insns and *_mems are paired lists. Each pending memory operation
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will have a pointer to the MEM rtx on one list and a pointer to the
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containing insn on the other list in the same place in the list. */
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/* We can't use add_dependence like the old code did, because a single insn
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may have multiple memory accesses, and hence needs to be on the list
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once for each memory access. Add_dependence won't let you add an insn
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to a list more than once. */
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/* An INSN_LIST containing all insns with pending read operations. */
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rtx pending_read_insns;
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/* An EXPR_LIST containing all MEM rtx's which are pending reads. */
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rtx pending_read_mems;
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/* An INSN_LIST containing all insns with pending write operations. */
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rtx pending_write_insns;
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/* An EXPR_LIST containing all MEM rtx's which are pending writes. */
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rtx pending_write_mems;
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/* Indicates the combined length of the two pending lists. We must prevent
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these lists from ever growing too large since the number of dependencies
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produced is at least O(N*N), and execution time is at least O(4*N*N), as
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a function of the length of these pending lists. */
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int pending_lists_length;
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/* Length of the pending memory flush list. Large functions with no
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calls may build up extremely large lists. */
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int pending_flush_length;
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/* The last insn upon which all memory references must depend.
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This is an insn which flushed the pending lists, creating a dependency
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between it and all previously pending memory references. This creates
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a barrier (or a checkpoint) which no memory reference is allowed to cross.
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This includes all non constant CALL_INSNs. When we do interprocedural
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alias analysis, this restriction can be relaxed.
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This may also be an INSN that writes memory if the pending lists grow
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too large. */
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rtx last_pending_memory_flush;
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/* A list of the last function calls we have seen. We use a list to
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represent last function calls from multiple predecessor blocks.
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Used to prevent register lifetimes from expanding unnecessarily. */
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rtx last_function_call;
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/* A list of insns which use a pseudo register that does not already
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cross a call. We create dependencies between each of those insn
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and the next call insn, to ensure that they won't cross a call after
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scheduling is done. */
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rtx sched_before_next_call;
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/* Used to keep post-call pseudo/hard reg movements together with
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the call. */
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enum { not_post_call, post_call, post_call_initial } in_post_call_group_p;
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/* Set to the tail insn of the outermost libcall block.
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When nonzero, we will mark each insn processed by sched_analyze_insn
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with SCHED_GROUP_P to ensure libcalls are scheduled as a unit. */
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rtx libcall_block_tail_insn;
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/* The maximum register number for the following arrays. Before reload
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this is max_reg_num; after reload it is FIRST_PSEUDO_REGISTER. */
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int max_reg;
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/* Element N is the next insn that sets (hard or pseudo) register
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N within the current basic block; or zero, if there is no
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such insn. Needed for new registers which may be introduced
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by splitting insns. */
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struct deps_reg
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{
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rtx uses;
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rtx sets;
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rtx clobbers;
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int uses_length;
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int clobbers_length;
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} *reg_last;
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/* Element N is set for each register that has any nonzero element
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in reg_last[N].{uses,sets,clobbers}. */
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regset_head reg_last_in_use;
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/* Element N is set for each register that is conditionally set. */
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regset_head reg_conditional_sets;
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};
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/* This structure holds some state of the current scheduling pass, and
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contains some function pointers that abstract out some of the non-generic
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functionality from functions such as schedule_block or schedule_insn.
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There is one global variable, current_sched_info, which points to the
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sched_info structure currently in use. */
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struct sched_info
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{
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/* Add all insns that are initially ready to the ready list. Called once
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before scheduling a set of insns. */
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void (*init_ready_list) (void);
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/* Called after taking an insn from the ready list. Returns nonzero if
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this insn can be scheduled, nonzero if we should silently discard it. */
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int (*can_schedule_ready_p) (rtx);
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/* Return nonzero if there are more insns that should be scheduled. */
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int (*schedule_more_p) (void);
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/* Called after an insn has all its hard dependencies resolved.
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Adjusts status of instruction (which is passed through second parameter)
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to indicate if instruction should be moved to the ready list or the
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queue, or if it should silently discard it (until next resolved
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dependence). */
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ds_t (*new_ready) (rtx, ds_t);
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/* Compare priority of two insns. Return a positive number if the second
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insn is to be preferred for scheduling, and a negative one if the first
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is to be preferred. Zero if they are equally good. */
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int (*rank) (rtx, rtx);
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/* Return a string that contains the insn uid and optionally anything else
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necessary to identify this insn in an output. It's valid to use a
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static buffer for this. The ALIGNED parameter should cause the string
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to be formatted so that multiple output lines will line up nicely. */
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const char *(*print_insn) (rtx, int);
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/* Return nonzero if an insn should be included in priority
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calculations. */
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int (*contributes_to_priority) (rtx, rtx);
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/* Called when computing dependencies for a JUMP_INSN. This function
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should store the set of registers that must be considered as set by
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the jump in the regset. */
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void (*compute_jump_reg_dependencies) (rtx, regset, regset, regset);
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/* The boundaries of the set of insns to be scheduled. */
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rtx prev_head, next_tail;
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/* Filled in after the schedule is finished; the first and last scheduled
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insns. */
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rtx head, tail;
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/* If nonzero, enables an additional sanity check in schedule_block. */
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unsigned int queue_must_finish_empty:1;
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/* Nonzero if we should use cselib for better alias analysis. This
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must be 0 if the dependency information is used after sched_analyze
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has completed, e.g. if we're using it to initialize state for successor
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blocks in region scheduling. */
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unsigned int use_cselib:1;
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/* Maximum priority that has been assigned to an insn. */
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int sched_max_insns_priority;
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/* Hooks to support speculative scheduling. */
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/* Called to notify frontend that instruction is being added (second
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parameter == 0) or removed (second parameter == 1). */
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void (*add_remove_insn) (rtx, int);
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/* Called to notify frontend that instruction is being scheduled.
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The first parameter - instruction to scheduled, the second parameter -
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last scheduled instruction. */
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void (*begin_schedule_ready) (rtx, rtx);
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/* Called to notify frontend, that new basic block is being added.
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The first parameter - new basic block.
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The second parameter - block, after which new basic block is being added,
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or EXIT_BLOCK_PTR, if recovery block is being added,
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or NULL, if standalone block is being added. */
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void (*add_block) (basic_block, basic_block);
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/* If the second parameter is not NULL, return nonnull value, if the
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basic block should be advanced.
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If the second parameter is NULL, return the next basic block in EBB.
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The first parameter is the current basic block in EBB. */
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basic_block (*advance_target_bb) (basic_block, rtx);
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/* Called after blocks were rearranged due to movement of jump instruction.
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The first parameter - index of basic block, in which jump currently is.
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The second parameter - index of basic block, in which jump used
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to be.
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The third parameter - index of basic block, that follows the second
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parameter. */
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void (*fix_recovery_cfg) (int, int, int);
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#ifdef ENABLE_CHECKING
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/* If the second parameter is zero, return nonzero, if block is head of the
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region.
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If the second parameter is nonzero, return nonzero, if block is leaf of
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the region.
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global_live_at_start should not change in region heads and
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global_live_at_end should not change in region leafs due to scheduling. */
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int (*region_head_or_leaf_p) (basic_block, int);
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#endif
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/* ??? FIXME: should use straight bitfields inside sched_info instead of
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this flag field. */
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unsigned int flags;
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};
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/* This structure holds description of the properties for speculative
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scheduling. */
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struct spec_info_def
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{
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/* Holds types of allowed speculations: BEGIN_{DATA|CONTROL},
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BE_IN_{DATA_CONTROL}. */
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int mask;
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/* A dump file for additional information on speculative scheduling. */
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FILE *dump;
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/* Minimal cumulative weakness of speculative instruction's
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dependencies, so that insn will be scheduled. */
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dw_t weakness_cutoff;
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/* Flags from the enum SPEC_SCHED_FLAGS. */
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int flags;
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};
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typedef struct spec_info_def *spec_info_t;
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extern struct sched_info *current_sched_info;
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/* Indexed by INSN_UID, the collection of all data associated with
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a single instruction. */
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struct haifa_insn_data
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{
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/* A list of insns which depend on the instruction. Unlike LOG_LINKS,
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it represents forward dependencies. */
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rtx depend;
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/* A list of scheduled producers of the instruction. Links are being moved
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from LOG_LINKS to RESOLVED_DEPS during scheduling. */
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rtx resolved_deps;
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/* The line number note in effect for each insn. For line number
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notes, this indicates whether the note may be reused. */
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rtx line_note;
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/* Logical uid gives the original ordering of the insns. */
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int luid;
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/* A priority for each insn. */
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int priority;
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/* The number of incoming edges in the forward dependency graph.
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As scheduling proceeds, counts are decreased. An insn moves to
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the ready queue when its counter reaches zero. */
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int dep_count;
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/* Number of instructions referring to this insn. */
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int ref_count;
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/* The minimum clock tick at which the insn becomes ready. This is
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used to note timing constraints for the insns in the pending list. */
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int tick;
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/* INTER_TICK is used to adjust INSN_TICKs of instructions from the
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subsequent blocks in a region. */
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int inter_tick;
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/* See comment on QUEUE_INDEX macro in haifa-sched.c. */
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int queue_index;
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short cost;
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/* This weight is an estimation of the insn's contribution to
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register pressure. */
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short reg_weight;
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/* Some insns (e.g. call) are not allowed to move across blocks. */
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unsigned int cant_move : 1;
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/* Set if there's DEF-USE dependence between some speculatively
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moved load insn and this one. */
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unsigned int fed_by_spec_load : 1;
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unsigned int is_load_insn : 1;
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/* Nonzero if priority has been computed already. */
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unsigned int priority_known : 1;
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/* Nonzero if instruction has internal dependence
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(e.g. add_dependence was invoked with (insn == elem)). */
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unsigned int has_internal_dep : 1;
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/* What speculations are necessary to apply to schedule the instruction. */
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ds_t todo_spec;
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/* What speculations were already applied. */
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ds_t done_spec;
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/* What speculations are checked by this instruction. */
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ds_t check_spec;
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/* Recovery block for speculation checks. */
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basic_block recovery_block;
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/* Original pattern of the instruction. */
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rtx orig_pat;
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};
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extern struct haifa_insn_data *h_i_d;
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/* Used only if (current_sched_info->flags & USE_GLAT) != 0.
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These regsets store global_live_at_{start, end} information
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for each basic block. */
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extern regset *glat_start, *glat_end;
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/* Accessor macros for h_i_d. There are more in haifa-sched.c and
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sched-rgn.c. */
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#define INSN_DEPEND(INSN) (h_i_d[INSN_UID (INSN)].depend)
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#define RESOLVED_DEPS(INSN) (h_i_d[INSN_UID (INSN)].resolved_deps)
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#define INSN_LUID(INSN) (h_i_d[INSN_UID (INSN)].luid)
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#define CANT_MOVE(insn) (h_i_d[INSN_UID (insn)].cant_move)
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#define INSN_DEP_COUNT(INSN) (h_i_d[INSN_UID (INSN)].dep_count)
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#define INSN_PRIORITY(INSN) (h_i_d[INSN_UID (INSN)].priority)
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#define INSN_PRIORITY_KNOWN(INSN) (h_i_d[INSN_UID (INSN)].priority_known)
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#define INSN_COST(INSN) (h_i_d[INSN_UID (INSN)].cost)
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#define INSN_REG_WEIGHT(INSN) (h_i_d[INSN_UID (INSN)].reg_weight)
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#define HAS_INTERNAL_DEP(INSN) (h_i_d[INSN_UID (INSN)].has_internal_dep)
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#define TODO_SPEC(INSN) (h_i_d[INSN_UID (INSN)].todo_spec)
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#define DONE_SPEC(INSN) (h_i_d[INSN_UID (INSN)].done_spec)
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#define CHECK_SPEC(INSN) (h_i_d[INSN_UID (INSN)].check_spec)
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#define RECOVERY_BLOCK(INSN) (h_i_d[INSN_UID (INSN)].recovery_block)
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#define ORIG_PAT(INSN) (h_i_d[INSN_UID (INSN)].orig_pat)
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/* INSN is either a simple or a branchy speculation check. */
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#define IS_SPECULATION_CHECK_P(INSN) (RECOVERY_BLOCK (INSN) != NULL)
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/* INSN is a speculation check that will simply reexecute the speculatively
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scheduled instruction if the speculation fails. */
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#define IS_SPECULATION_SIMPLE_CHECK_P(INSN) \
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(RECOVERY_BLOCK (INSN) == EXIT_BLOCK_PTR)
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/* INSN is a speculation check that will branch to RECOVERY_BLOCK if the
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speculation fails. Insns in that block will reexecute the speculatively
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scheduled code and then will return immediately after INSN thus preserving
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semantics of the program. */
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#define IS_SPECULATION_BRANCHY_CHECK_P(INSN) \
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(RECOVERY_BLOCK (INSN) != NULL && RECOVERY_BLOCK (INSN) != EXIT_BLOCK_PTR)
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/* DEP_STATUS of the link encapsulates information, that is needed for
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speculative scheduling. Namely, it is 4 integers in the range
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[0, MAX_DEP_WEAK] and 3 bits.
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The integers correspond to the probability of the dependence to *not*
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exist, it is the probability, that overcoming of this dependence will
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not be followed by execution of the recovery code. Nevertheless,
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whatever high the probability of success is, recovery code should still
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be generated to preserve semantics of the program. To find a way to
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get/set these integers, please refer to the {get, set}_dep_weak ()
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functions in sched-deps.c .
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The 3 bits in the DEP_STATUS correspond to 3 dependence types: true-,
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output- and anti- dependence. It is not enough for speculative scheduling
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to know just the major type of all the dependence between two instructions,
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as only true dependence can be overcome.
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There also is the 4-th bit in the DEP_STATUS (HARD_DEP), that is reserved
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for using to describe instruction's status. It is set whenever instruction
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has at least one dependence, that cannot be overcome.
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See also: check_dep_status () in sched-deps.c . */
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#define DEP_STATUS(LINK) XINT (LINK, 2)
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/* We exclude sign bit. */
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#define BITS_PER_DEP_STATUS (HOST_BITS_PER_INT - 1)
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/* First '4' stands for 3 dep type bits and HARD_DEP bit.
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Second '4' stands for BEGIN_{DATA, CONTROL}, BE_IN_{DATA, CONTROL}
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dep weakness. */
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#define BITS_PER_DEP_WEAK ((BITS_PER_DEP_STATUS - 4) / 4)
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/* Mask of speculative weakness in dep_status. */
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#define DEP_WEAK_MASK ((1 << BITS_PER_DEP_WEAK) - 1)
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/* This constant means that dependence is fake with 99.999...% probability.
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This is the maximum value, that can appear in dep_status.
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Note, that we don't want MAX_DEP_WEAK to be the same as DEP_WEAK_MASK for
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debugging reasons. Though, it can be set to DEP_WEAK_MASK, and, when
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done so, we'll get fast (mul for)/(div by) NO_DEP_WEAK. */
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#define MAX_DEP_WEAK (DEP_WEAK_MASK - 1)
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/* This constant means that dependence is 99.999...% real and it is a really
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bad idea to overcome it (though this can be done, preserving program
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semantics). */
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#define MIN_DEP_WEAK 1
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/* This constant represents 100% probability.
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E.g. it is used to represent weakness of dependence, that doesn't exist. */
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#define NO_DEP_WEAK (MAX_DEP_WEAK + MIN_DEP_WEAK)
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/* Default weakness of speculative dependence. Used when we can't say
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neither bad nor good about the dependence. */
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#define UNCERTAIN_DEP_WEAK (MAX_DEP_WEAK - MAX_DEP_WEAK / 4)
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/* Offset for speculative weaknesses in dep_status. */
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enum SPEC_TYPES_OFFSETS {
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BEGIN_DATA_BITS_OFFSET = 0,
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BE_IN_DATA_BITS_OFFSET = BEGIN_DATA_BITS_OFFSET + BITS_PER_DEP_WEAK,
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BEGIN_CONTROL_BITS_OFFSET = BE_IN_DATA_BITS_OFFSET + BITS_PER_DEP_WEAK,
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BE_IN_CONTROL_BITS_OFFSET = BEGIN_CONTROL_BITS_OFFSET + BITS_PER_DEP_WEAK
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};
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/* The following defines provide numerous constants used to distinguish between
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different types of speculative dependencies. */
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/* Dependence can be overcome with generation of new data speculative
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instruction. */
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#define BEGIN_DATA (((ds_t) DEP_WEAK_MASK) << BEGIN_DATA_BITS_OFFSET)
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/* This dependence is to the instruction in the recovery block, that was
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formed to recover after data-speculation failure.
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Thus, this dependence can overcome with generating of the copy of
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this instruction in the recovery block. */
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#define BE_IN_DATA (((ds_t) DEP_WEAK_MASK) << BE_IN_DATA_BITS_OFFSET)
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/* Dependence can be overcome with generation of new control speculative
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instruction. */
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#define BEGIN_CONTROL (((ds_t) DEP_WEAK_MASK) << BEGIN_CONTROL_BITS_OFFSET)
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/* This dependence is to the instruction in the recovery block, that was
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formed to recover after control-speculation failure.
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Thus, this dependence can be overcome with generating of the copy of
|
|
this instruction in the recovery block. */
|
|
#define BE_IN_CONTROL (((ds_t) DEP_WEAK_MASK) << BE_IN_CONTROL_BITS_OFFSET)
|
|
|
|
/* A few convenient combinations. */
|
|
#define BEGIN_SPEC (BEGIN_DATA | BEGIN_CONTROL)
|
|
#define DATA_SPEC (BEGIN_DATA | BE_IN_DATA)
|
|
#define CONTROL_SPEC (BEGIN_CONTROL | BE_IN_CONTROL)
|
|
#define SPECULATIVE (DATA_SPEC | CONTROL_SPEC)
|
|
#define BE_IN_SPEC (BE_IN_DATA | BE_IN_CONTROL)
|
|
|
|
/* Constants, that are helpful in iterating through dep_status. */
|
|
#define FIRST_SPEC_TYPE BEGIN_DATA
|
|
#define LAST_SPEC_TYPE BE_IN_CONTROL
|
|
#define SPEC_TYPE_SHIFT BITS_PER_DEP_WEAK
|
|
|
|
/* Dependence on instruction can be of multiple types
|
|
(e.g. true and output). This fields enhance REG_NOTE_KIND information
|
|
of the dependence. */
|
|
#define DEP_TRUE (((ds_t) 1) << (BE_IN_CONTROL_BITS_OFFSET + BITS_PER_DEP_WEAK))
|
|
#define DEP_OUTPUT (DEP_TRUE << 1)
|
|
#define DEP_ANTI (DEP_OUTPUT << 1)
|
|
|
|
#define DEP_TYPES (DEP_TRUE | DEP_OUTPUT | DEP_ANTI)
|
|
|
|
/* Instruction has non-speculative dependence. This bit represents the
|
|
property of an instruction - not the one of a dependence.
|
|
Therefore, it can appear only in TODO_SPEC field of an instruction. */
|
|
#define HARD_DEP (DEP_ANTI << 1)
|
|
|
|
/* This represents the results of calling sched-deps.c functions,
|
|
which modify dependencies. Possible choices are: a dependence
|
|
is already present and nothing has been changed; a dependence type
|
|
has been changed; brand new dependence has been created. */
|
|
enum DEPS_ADJUST_RESULT {
|
|
DEP_PRESENT = 1,
|
|
DEP_CHANGED = 2,
|
|
DEP_CREATED = 3
|
|
};
|
|
|
|
/* Represents the bits that can be set in the flags field of the
|
|
sched_info structure. */
|
|
enum SCHED_FLAGS {
|
|
/* If set, generate links between instruction as DEPS_LIST.
|
|
Otherwise, generate usual INSN_LIST links. */
|
|
USE_DEPS_LIST = 1,
|
|
/* Perform data or control (or both) speculation.
|
|
Results in generation of data and control speculative dependencies.
|
|
Requires USE_DEPS_LIST set. */
|
|
DO_SPECULATION = USE_DEPS_LIST << 1,
|
|
SCHED_RGN = DO_SPECULATION << 1,
|
|
SCHED_EBB = SCHED_RGN << 1,
|
|
/* Detach register live information from basic block headers.
|
|
This is necessary to invoke functions, that change CFG (e.g. split_edge).
|
|
Requires USE_GLAT. */
|
|
DETACH_LIFE_INFO = SCHED_EBB << 1,
|
|
/* Save register live information from basic block headers to
|
|
glat_{start, end} arrays. */
|
|
USE_GLAT = DETACH_LIFE_INFO << 1
|
|
};
|
|
|
|
enum SPEC_SCHED_FLAGS {
|
|
COUNT_SPEC_IN_CRITICAL_PATH = 1,
|
|
PREFER_NON_DATA_SPEC = COUNT_SPEC_IN_CRITICAL_PATH << 1,
|
|
PREFER_NON_CONTROL_SPEC = PREFER_NON_DATA_SPEC << 1
|
|
};
|
|
|
|
#define NOTE_NOT_BB_P(NOTE) (NOTE_P (NOTE) && (NOTE_LINE_NUMBER (NOTE) \
|
|
!= NOTE_INSN_BASIC_BLOCK))
|
|
|
|
extern FILE *sched_dump;
|
|
extern int sched_verbose;
|
|
|
|
/* Exception Free Loads:
|
|
|
|
We define five classes of speculative loads: IFREE, IRISKY,
|
|
PFREE, PRISKY, and MFREE.
|
|
|
|
IFREE loads are loads that are proved to be exception-free, just
|
|
by examining the load insn. Examples for such loads are loads
|
|
from TOC and loads of global data.
|
|
|
|
IRISKY loads are loads that are proved to be exception-risky,
|
|
just by examining the load insn. Examples for such loads are
|
|
volatile loads and loads from shared memory.
|
|
|
|
PFREE loads are loads for which we can prove, by examining other
|
|
insns, that they are exception-free. Currently, this class consists
|
|
of loads for which we are able to find a "similar load", either in
|
|
the target block, or, if only one split-block exists, in that split
|
|
block. Load2 is similar to load1 if both have same single base
|
|
register. We identify only part of the similar loads, by finding
|
|
an insn upon which both load1 and load2 have a DEF-USE dependence.
|
|
|
|
PRISKY loads are loads for which we can prove, by examining other
|
|
insns, that they are exception-risky. Currently we have two proofs for
|
|
such loads. The first proof detects loads that are probably guarded by a
|
|
test on the memory address. This proof is based on the
|
|
backward and forward data dependence information for the region.
|
|
Let load-insn be the examined load.
|
|
Load-insn is PRISKY iff ALL the following hold:
|
|
|
|
- insn1 is not in the same block as load-insn
|
|
- there is a DEF-USE dependence chain (insn1, ..., load-insn)
|
|
- test-insn is either a compare or a branch, not in the same block
|
|
as load-insn
|
|
- load-insn is reachable from test-insn
|
|
- there is a DEF-USE dependence chain (insn1, ..., test-insn)
|
|
|
|
This proof might fail when the compare and the load are fed
|
|
by an insn not in the region. To solve this, we will add to this
|
|
group all loads that have no input DEF-USE dependence.
|
|
|
|
The second proof detects loads that are directly or indirectly
|
|
fed by a speculative load. This proof is affected by the
|
|
scheduling process. We will use the flag fed_by_spec_load.
|
|
Initially, all insns have this flag reset. After a speculative
|
|
motion of an insn, if insn is either a load, or marked as
|
|
fed_by_spec_load, we will also mark as fed_by_spec_load every
|
|
insn1 for which a DEF-USE dependence (insn, insn1) exists. A
|
|
load which is fed_by_spec_load is also PRISKY.
|
|
|
|
MFREE (maybe-free) loads are all the remaining loads. They may be
|
|
exception-free, but we cannot prove it.
|
|
|
|
Now, all loads in IFREE and PFREE classes are considered
|
|
exception-free, while all loads in IRISKY and PRISKY classes are
|
|
considered exception-risky. As for loads in the MFREE class,
|
|
these are considered either exception-free or exception-risky,
|
|
depending on whether we are pessimistic or optimistic. We have
|
|
to take the pessimistic approach to assure the safety of
|
|
speculative scheduling, but we can take the optimistic approach
|
|
by invoking the -fsched_spec_load_dangerous option. */
|
|
|
|
enum INSN_TRAP_CLASS
|
|
{
|
|
TRAP_FREE = 0, IFREE = 1, PFREE_CANDIDATE = 2,
|
|
PRISKY_CANDIDATE = 3, IRISKY = 4, TRAP_RISKY = 5
|
|
};
|
|
|
|
#define WORST_CLASS(class1, class2) \
|
|
((class1 > class2) ? class1 : class2)
|
|
|
|
#ifndef __GNUC__
|
|
#define __inline
|
|
#endif
|
|
|
|
#ifndef HAIFA_INLINE
|
|
#define HAIFA_INLINE __inline
|
|
#endif
|
|
|
|
/* Functions in sched-vis.c. */
|
|
extern void print_insn (char *, rtx, int);
|
|
|
|
/* Functions in sched-deps.c. */
|
|
extern bool sched_insns_conditions_mutex_p (rtx, rtx);
|
|
extern void add_dependence (rtx, rtx, enum reg_note);
|
|
extern void sched_analyze (struct deps *, rtx, rtx);
|
|
extern void init_deps (struct deps *);
|
|
extern void free_deps (struct deps *);
|
|
extern void init_deps_global (void);
|
|
extern void finish_deps_global (void);
|
|
extern void add_forw_dep (rtx, rtx);
|
|
extern void compute_forward_dependences (rtx, rtx);
|
|
extern rtx find_insn_list (rtx, rtx);
|
|
extern void init_dependency_caches (int);
|
|
extern void free_dependency_caches (void);
|
|
extern void extend_dependency_caches (int, bool);
|
|
extern enum DEPS_ADJUST_RESULT add_or_update_back_dep (rtx, rtx,
|
|
enum reg_note, ds_t);
|
|
extern void add_or_update_back_forw_dep (rtx, rtx, enum reg_note, ds_t);
|
|
extern void add_back_forw_dep (rtx, rtx, enum reg_note, ds_t);
|
|
extern void delete_back_forw_dep (rtx, rtx);
|
|
extern dw_t get_dep_weak (ds_t, ds_t);
|
|
extern ds_t set_dep_weak (ds_t, ds_t, dw_t);
|
|
extern ds_t ds_merge (ds_t, ds_t);
|
|
|
|
/* Functions in haifa-sched.c. */
|
|
extern int haifa_classify_insn (rtx);
|
|
extern void get_ebb_head_tail (basic_block, basic_block, rtx *, rtx *);
|
|
extern int no_real_insns_p (rtx, rtx);
|
|
|
|
extern void rm_line_notes (rtx, rtx);
|
|
extern void save_line_notes (int, rtx, rtx);
|
|
extern void restore_line_notes (rtx, rtx);
|
|
extern void rm_redundant_line_notes (void);
|
|
extern void rm_other_notes (rtx, rtx);
|
|
|
|
extern int insn_cost (rtx, rtx, rtx);
|
|
extern int set_priorities (rtx, rtx);
|
|
|
|
extern void schedule_block (basic_block *, int);
|
|
extern void sched_init (void);
|
|
extern void sched_finish (void);
|
|
|
|
extern int try_ready (rtx);
|
|
extern void * xrecalloc (void *, size_t, size_t, size_t);
|
|
extern void unlink_bb_notes (basic_block, basic_block);
|
|
extern void add_block (basic_block, basic_block);
|
|
extern void attach_life_info (void);
|
|
extern rtx bb_note (basic_block);
|
|
|
|
#ifdef ENABLE_CHECKING
|
|
extern void check_reg_live (bool);
|
|
#endif
|
|
|
|
#endif /* GCC_SCHED_INT_H */
|