/* Instruction scheduling pass. Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc. Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by, and currently maintained by, Jim Wilson (wilson@cygnus.com) This file is part of GCC. GCC 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 3, or (at your option) any later version. GCC 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 GCC; see the file COPYING3. If not see . */ /* Instruction scheduling pass. This file, along with sched-deps.c, contains the generic parts. The actual entry point is found for the normal instruction scheduling pass is found in sched-rgn.c. We compute insn priorities based on data dependencies. Flow analysis only creates a fraction of the data-dependencies we must observe: namely, only those dependencies which the combiner can be expected to use. For this pass, we must therefore create the remaining dependencies we need to observe: register dependencies, memory dependencies, dependencies to keep function calls in order, and the dependence between a conditional branch and the setting of condition codes are all dealt with here. The scheduler first traverses the data flow graph, starting with the last instruction, and proceeding to the first, assigning values to insn_priority as it goes. This sorts the instructions topologically by data dependence. Once priorities have been established, we order the insns using list scheduling. This works as follows: starting with a list of all the ready insns, and sorted according to priority number, we schedule the insn from the end of the list by placing its predecessors in the list according to their priority order. We consider this insn scheduled by setting the pointer to the "end" of the list to point to the previous insn. When an insn has no predecessors, we either queue it until sufficient time has elapsed or add it to the ready list. As the instructions are scheduled or when stalls are introduced, the queue advances and dumps insns into the ready list. When all insns down to the lowest priority have been scheduled, the critical path of the basic block has been made as short as possible. The remaining insns are then scheduled in remaining slots. The following list shows the order in which we want to break ties among insns in the ready list: 1. choose insn with the longest path to end of bb, ties broken by 2. choose insn with least contribution to register pressure, ties broken by 3. prefer in-block upon interblock motion, ties broken by 4. prefer useful upon speculative motion, ties broken by 5. choose insn with largest control flow probability, ties broken by 6. choose insn with the least dependences upon the previously scheduled insn, or finally 7 choose the insn which has the most insns dependent on it. 8. choose insn with lowest UID. Memory references complicate matters. Only if we can be certain that memory references are not part of the data dependency graph (via true, anti, or output dependence), can we move operations past memory references. To first approximation, reads can be done independently, while writes introduce dependencies. Better approximations will yield fewer dependencies. Before reload, an extended analysis of interblock data dependences is required for interblock scheduling. This is performed in compute_block_backward_dependences (). Dependencies set up by memory references are treated in exactly the same way as other dependencies, by using insn backward dependences INSN_BACK_DEPS. INSN_BACK_DEPS are translated into forward dependences INSN_FORW_DEPS the purpose of forward list scheduling. Having optimized the critical path, we may have also unduly extended the lifetimes of some registers. If an operation requires that constants be loaded into registers, it is certainly desirable to load those constants as early as necessary, but no earlier. I.e., it will not do to load up a bunch of registers at the beginning of a basic block only to use them at the end, if they could be loaded later, since this may result in excessive register utilization. Note that since branches are never in basic blocks, but only end basic blocks, this pass will not move branches. But that is ok, since we can use GNU's delayed branch scheduling pass to take care of this case. Also note that no further optimizations based on algebraic identities are performed, so this pass would be a good one to perform instruction splitting, such as breaking up a multiply instruction into shifts and adds where that is profitable. Given the memory aliasing analysis that this pass should perform, it should be possible to remove redundant stores to memory, and to load values from registers instead of hitting memory. Before reload, speculative insns are moved only if a 'proof' exists that no exception will be caused by this, and if no live registers exist that inhibit the motion (live registers constraints are not represented by data dependence edges). This pass must update information that subsequent passes expect to be correct. Namely: reg_n_refs, reg_n_sets, reg_n_deaths, reg_n_calls_crossed, and reg_live_length. Also, BB_HEAD, BB_END. The information in the line number notes is carefully retained by this pass. Notes that refer to the starting and ending of exception regions are also carefully retained by this pass. All other NOTE insns are grouped in their same relative order at the beginning of basic blocks and regions that have been scheduled. */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "toplev.h" #include "rtl.h" #include "tm_p.h" #include "hard-reg-set.h" #include "regs.h" #include "function.h" #include "flags.h" #include "insn-config.h" #include "insn-attr.h" #include "except.h" #include "toplev.h" #include "recog.h" #include "sched-int.h" #include "target.h" #include "output.h" #include "params.h" #include "dbgcnt.h" #ifdef INSN_SCHEDULING /* issue_rate is the number of insns that can be scheduled in the same machine cycle. It can be defined in the config/mach/mach.h file, otherwise we set it to 1. */ static int issue_rate; /* sched-verbose controls the amount of debugging output the scheduler prints. It is controlled by -fsched-verbose=N: N>0 and no -DSR : the output is directed to stderr. N>=10 will direct the printouts to stderr (regardless of -dSR). N=1: same as -dSR. N=2: bb's probabilities, detailed ready list info, unit/insn info. N=3: rtl at abort point, control-flow, regions info. N=5: dependences info. */ static int sched_verbose_param = 0; int sched_verbose = 0; /* Debugging file. All printouts are sent to dump, which is always set, either to stderr, or to the dump listing file (-dRS). */ FILE *sched_dump = 0; /* Highest uid before scheduling. */ static int old_max_uid; /* fix_sched_param() is called from toplev.c upon detection of the -fsched-verbose=N option. */ void fix_sched_param (const char *param, const char *val) { if (!strcmp (param, "verbose")) sched_verbose_param = atoi (val); else warning (0, "fix_sched_param: unknown param: %s", param); } struct haifa_insn_data *h_i_d; #define INSN_TICK(INSN) (h_i_d[INSN_UID (INSN)].tick) #define INTER_TICK(INSN) (h_i_d[INSN_UID (INSN)].inter_tick) /* If INSN_TICK of an instruction is equal to INVALID_TICK, then it should be recalculated from scratch. */ #define INVALID_TICK (-(max_insn_queue_index + 1)) /* The minimal value of the INSN_TICK of an instruction. */ #define MIN_TICK (-max_insn_queue_index) /* Issue points are used to distinguish between instructions in max_issue (). For now, all instructions are equally good. */ #define ISSUE_POINTS(INSN) 1 /* List of important notes we must keep around. This is a pointer to the last element in the list. */ static rtx note_list; static struct spec_info_def spec_info_var; /* Description of the speculative part of the scheduling. If NULL - no speculation. */ spec_info_t spec_info; /* True, if recovery block was added during scheduling of current block. Used to determine, if we need to fix INSN_TICKs. */ static bool haifa_recovery_bb_recently_added_p; /* True, if recovery block was added during this scheduling pass. Used to determine if we should have empty memory pools of dependencies after finishing current region. */ bool haifa_recovery_bb_ever_added_p; /* Counters of different types of speculative instructions. */ static int nr_begin_data, nr_be_in_data, nr_begin_control, nr_be_in_control; /* Array used in {unlink, restore}_bb_notes. */ static rtx *bb_header = 0; /* Number of basic_blocks. */ static int old_last_basic_block; /* Basic block after which recovery blocks will be created. */ static basic_block before_recovery; /* Queues, etc. */ /* An instruction is ready to be scheduled when all insns preceding it have already been scheduled. It is important to ensure that all insns which use its result will not be executed until its result has been computed. An insn is maintained in one of four structures: (P) the "Pending" set of insns which cannot be scheduled until their dependencies have been satisfied. (Q) the "Queued" set of insns that can be scheduled when sufficient time has passed. (R) the "Ready" list of unscheduled, uncommitted insns. (S) the "Scheduled" list of insns. Initially, all insns are either "Pending" or "Ready" depending on whether their dependencies are satisfied. Insns move from the "Ready" list to the "Scheduled" list as they are committed to the schedule. As this occurs, the insns in the "Pending" list have their dependencies satisfied and move to either the "Ready" list or the "Queued" set depending on whether sufficient time has passed to make them ready. As time passes, insns move from the "Queued" set to the "Ready" list. The "Pending" list (P) are the insns in the INSN_FORW_DEPS of the unscheduled insns, i.e., those that are ready, queued, and pending. The "Queued" set (Q) is implemented by the variable `insn_queue'. The "Ready" list (R) is implemented by the variables `ready' and `n_ready'. The "Scheduled" list (S) is the new insn chain built by this pass. The transition (R->S) is implemented in the scheduling loop in `schedule_block' when the best insn to schedule is chosen. The transitions (P->R and P->Q) are implemented in `schedule_insn' as insns move from the ready list to the scheduled list. The transition (Q->R) is implemented in 'queue_to_insn' as time passes or stalls are introduced. */ /* Implement a circular buffer to delay instructions until sufficient time has passed. For the new pipeline description interface, MAX_INSN_QUEUE_INDEX is a power of two minus one which is not less than maximal time of instruction execution computed by genattr.c on the base maximal time of functional unit reservations and getting a result. This is the longest time an insn may be queued. */ static rtx *insn_queue; static int q_ptr = 0; static int q_size = 0; #define NEXT_Q(X) (((X)+1) & max_insn_queue_index) #define NEXT_Q_AFTER(X, C) (((X)+C) & max_insn_queue_index) #define QUEUE_SCHEDULED (-3) #define QUEUE_NOWHERE (-2) #define QUEUE_READY (-1) /* QUEUE_SCHEDULED - INSN is scheduled. QUEUE_NOWHERE - INSN isn't scheduled yet and is neither in queue or ready list. QUEUE_READY - INSN is in ready list. N >= 0 - INSN queued for X [where NEXT_Q_AFTER (q_ptr, X) == N] cycles. */ #define QUEUE_INDEX(INSN) (h_i_d[INSN_UID (INSN)].queue_index) /* The following variable value refers for all current and future reservations of the processor units. */ state_t curr_state; /* The following variable value is size of memory representing all current and future reservations of the processor units. */ static size_t dfa_state_size; /* The following array is used to find the best insn from ready when the automaton pipeline interface is used. */ static char *ready_try; /* Describe the ready list of the scheduler. VEC holds space enough for all insns in the current region. VECLEN says how many exactly. FIRST is the index of the element with the highest priority; i.e. the last one in the ready list, since elements are ordered by ascending priority. N_READY determines how many insns are on the ready list. */ struct ready_list { rtx *vec; int veclen; int first; int n_ready; }; /* The pointer to the ready list. */ static struct ready_list *readyp; /* Scheduling clock. */ static int clock_var; /* Number of instructions in current scheduling region. */ static int rgn_n_insns; static int may_trap_exp (const_rtx, int); /* Nonzero iff the address is comprised from at most 1 register. */ #define CONST_BASED_ADDRESS_P(x) \ (REG_P (x) \ || ((GET_CODE (x) == PLUS || GET_CODE (x) == MINUS \ || (GET_CODE (x) == LO_SUM)) \ && (CONSTANT_P (XEXP (x, 0)) \ || CONSTANT_P (XEXP (x, 1))))) /* Returns a class that insn with GET_DEST(insn)=x may belong to, as found by analyzing insn's expression. */ static int may_trap_exp (const_rtx x, int is_store) { enum rtx_code code; if (x == 0) return TRAP_FREE; code = GET_CODE (x); if (is_store) { if (code == MEM && may_trap_p (x)) return TRAP_RISKY; else return TRAP_FREE; } if (code == MEM) { /* The insn uses memory: a volatile load. */ if (MEM_VOLATILE_P (x)) return IRISKY; /* An exception-free load. */ if (!may_trap_p (x)) return IFREE; /* A load with 1 base register, to be further checked. */ if (CONST_BASED_ADDRESS_P (XEXP (x, 0))) return PFREE_CANDIDATE; /* No info on the load, to be further checked. */ return PRISKY_CANDIDATE; } else { const char *fmt; int i, insn_class = TRAP_FREE; /* Neither store nor load, check if it may cause a trap. */ if (may_trap_p (x)) return TRAP_RISKY; /* Recursive step: walk the insn... */ fmt = GET_RTX_FORMAT (code); for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) { if (fmt[i] == 'e') { int tmp_class = may_trap_exp (XEXP (x, i), is_store); insn_class = WORST_CLASS (insn_class, tmp_class); } else if (fmt[i] == 'E') { int j; for (j = 0; j < XVECLEN (x, i); j++) { int tmp_class = may_trap_exp (XVECEXP (x, i, j), is_store); insn_class = WORST_CLASS (insn_class, tmp_class); if (insn_class == TRAP_RISKY || insn_class == IRISKY) break; } } if (insn_class == TRAP_RISKY || insn_class == IRISKY) break; } return insn_class; } } /* Classifies rtx X of an insn for the purpose of verifying that X can be executed speculatively (and consequently the insn can be moved speculatively), by examining X, returning: TRAP_RISKY: store, or risky non-load insn (e.g. division by variable). TRAP_FREE: non-load insn. IFREE: load from a globally safe location. IRISKY: volatile load. PFREE_CANDIDATE, PRISKY_CANDIDATE: load that need to be checked for being either PFREE or PRISKY. */ static int haifa_classify_rtx (const_rtx x) { int tmp_class = TRAP_FREE; int insn_class = TRAP_FREE; enum rtx_code code; if (GET_CODE (x) == PARALLEL) { int i, len = XVECLEN (x, 0); for (i = len - 1; i >= 0; i--) { tmp_class = haifa_classify_rtx (XVECEXP (x, 0, i)); insn_class = WORST_CLASS (insn_class, tmp_class); if (insn_class == TRAP_RISKY || insn_class == IRISKY) break; } } else { code = GET_CODE (x); switch (code) { case CLOBBER: /* Test if it is a 'store'. */ tmp_class = may_trap_exp (XEXP (x, 0), 1); break; case SET: /* Test if it is a store. */ tmp_class = may_trap_exp (SET_DEST (x), 1); if (tmp_class == TRAP_RISKY) break; /* Test if it is a load. */ tmp_class = WORST_CLASS (tmp_class, may_trap_exp (SET_SRC (x), 0)); break; case COND_EXEC: tmp_class = haifa_classify_rtx (COND_EXEC_CODE (x)); if (tmp_class == TRAP_RISKY) break; tmp_class = WORST_CLASS (tmp_class, may_trap_exp (COND_EXEC_TEST (x), 0)); break; case TRAP_IF: tmp_class = TRAP_RISKY; break; default:; } insn_class = tmp_class; } return insn_class; } int haifa_classify_insn (const_rtx insn) { return haifa_classify_rtx (PATTERN (insn)); } /* A typedef for rtx vector. */ typedef VEC(rtx, heap) *rtx_vec_t; /* Forward declarations. */ static int priority (rtx); static int rank_for_schedule (const void *, const void *); static void swap_sort (rtx *, int); static void queue_insn (rtx, int); static int schedule_insn (rtx); static int find_set_reg_weight (const_rtx); static void find_insn_reg_weight (basic_block); static void find_insn_reg_weight1 (rtx); static void adjust_priority (rtx); static void advance_one_cycle (void); /* Notes handling mechanism: ========================= Generally, NOTES are saved before scheduling and restored after scheduling. The scheduler distinguishes between two types of notes: (1) LOOP_BEGIN, LOOP_END, SETJMP, EHREGION_BEG, EHREGION_END notes: Before scheduling a region, a pointer to the note is added to the insn that follows or precedes it. (This happens as part of the data dependence computation). After scheduling an insn, the pointer contained in it is used for regenerating the corresponding note (in reemit_notes). (2) All other notes (e.g. INSN_DELETED): Before scheduling a block, these notes are put in a list (in rm_other_notes() and unlink_other_notes ()). After scheduling the block, these notes are inserted at the beginning of the block (in schedule_block()). */ static rtx unlink_other_notes (rtx, rtx); static void reemit_notes (rtx); static rtx *ready_lastpos (struct ready_list *); static void ready_add (struct ready_list *, rtx, bool); static void ready_sort (struct ready_list *); static rtx ready_remove_first (struct ready_list *); static void queue_to_ready (struct ready_list *); static int early_queue_to_ready (state_t, struct ready_list *); static void debug_ready_list (struct ready_list *); static void move_insn (rtx); /* The following functions are used to implement multi-pass scheduling on the first cycle. */ static rtx ready_element (struct ready_list *, int); static rtx ready_remove (struct ready_list *, int); static void ready_remove_insn (rtx); static int max_issue (struct ready_list *, int *, int); static int choose_ready (struct ready_list *, rtx *); static void fix_inter_tick (rtx, rtx); static int fix_tick_ready (rtx); static void change_queue_index (rtx, int); /* The following functions are used to implement scheduling of data/control speculative instructions. */ static void extend_h_i_d (void); static void extend_ready (int); static void extend_global (rtx); static void extend_all (rtx); static void init_h_i_d (rtx); static void generate_recovery_code (rtx); static void process_insn_forw_deps_be_in_spec (rtx, rtx, ds_t); static void begin_speculative_block (rtx); static void add_to_speculative_block (rtx); static dw_t dep_weak (ds_t); static edge find_fallthru_edge (basic_block); static void init_before_recovery (void); static basic_block create_recovery_block (void); static void create_check_block_twin (rtx, bool); static void fix_recovery_deps (basic_block); static void change_pattern (rtx, rtx); static int speculate_insn (rtx, ds_t, rtx *); static void dump_new_block_header (int, basic_block, rtx, rtx); static void restore_bb_notes (basic_block); static void extend_bb (void); static void fix_jump_move (rtx); static void move_block_after_check (rtx); static void move_succs (VEC(edge,gc) **, basic_block); static void sched_remove_insn (rtx); static void clear_priorities (rtx, rtx_vec_t *); static void calc_priorities (rtx_vec_t); static void add_jump_dependencies (rtx, rtx); #ifdef ENABLE_CHECKING static int has_edge_p (VEC(edge,gc) *, int); static void check_cfg (rtx, rtx); #endif #endif /* INSN_SCHEDULING */ /* Point to state used for the current scheduling pass. */ struct sched_info *current_sched_info; #ifndef INSN_SCHEDULING void schedule_insns (void) { } #else /* Working copy of frontend's sched_info variable. */ static struct sched_info current_sched_info_var; /* Pointer to the last instruction scheduled. Used by rank_for_schedule, so that insns independent of the last scheduled insn will be preferred over dependent instructions. */ static rtx last_scheduled_insn; /* Cached cost of the instruction. Use below function to get cost of the insn. -1 here means that the field is not initialized. */ #define INSN_COST(INSN) (h_i_d[INSN_UID (INSN)].cost) /* Compute cost of executing INSN. This is the number of cycles between instruction issue and instruction results. */ HAIFA_INLINE int insn_cost (rtx insn) { int cost = INSN_COST (insn); if (cost < 0) { /* A USE insn, or something else we don't need to understand. We can't pass these directly to result_ready_cost or insn_default_latency because it will trigger a fatal error for unrecognizable insns. */ if (recog_memoized (insn) < 0) { INSN_COST (insn) = 0; return 0; } else { cost = insn_default_latency (insn); if (cost < 0) cost = 0; INSN_COST (insn) = cost; } } return cost; } /* Compute cost of dependence LINK. This is the number of cycles between instruction issue and instruction results. */ int dep_cost (dep_t link) { rtx used = DEP_CON (link); int cost; /* A USE insn should never require the value used to be computed. This allows the computation of a function's result and parameter values to overlap the return and call. */ if (recog_memoized (used) < 0) cost = 0; else { rtx insn = DEP_PRO (link); enum reg_note dep_type = DEP_TYPE (link); cost = insn_cost (insn); if (INSN_CODE (insn) >= 0) { if (dep_type == REG_DEP_ANTI) cost = 0; else if (dep_type == REG_DEP_OUTPUT) { cost = (insn_default_latency (insn) - insn_default_latency (used)); if (cost <= 0) cost = 1; } else if (bypass_p (insn)) cost = insn_latency (insn, used); } if (targetm.sched.adjust_cost != NULL) { /* This variable is used for backward compatibility with the targets. */ rtx dep_cost_rtx_link = alloc_INSN_LIST (NULL_RTX, NULL_RTX); /* Make it self-cycled, so that if some tries to walk over this incomplete list he/she will be caught in an endless loop. */ XEXP (dep_cost_rtx_link, 1) = dep_cost_rtx_link; /* Targets use only REG_NOTE_KIND of the link. */ PUT_REG_NOTE_KIND (dep_cost_rtx_link, DEP_TYPE (link)); cost = targetm.sched.adjust_cost (used, dep_cost_rtx_link, insn, cost); free_INSN_LIST_node (dep_cost_rtx_link); } if (cost < 0) cost = 0; } return cost; } /* Return 'true' if DEP should be included in priority calculations. */ static bool contributes_to_priority_p (dep_t dep) { /* Critical path is meaningful in block boundaries only. */ if (!current_sched_info->contributes_to_priority (DEP_CON (dep), DEP_PRO (dep))) return false; /* If flag COUNT_SPEC_IN_CRITICAL_PATH is set, then speculative instructions will less likely be scheduled. That is because the priority of their producers will increase, and, thus, the producers will more likely be scheduled, thus, resolving the dependence. */ if ((current_sched_info->flags & DO_SPECULATION) && !(spec_info->flags & COUNT_SPEC_IN_CRITICAL_PATH) && (DEP_STATUS (dep) & SPECULATIVE)) return false; return true; } /* Compute the priority number for INSN. */ static int priority (rtx insn) { if (! INSN_P (insn)) return 0; /* We should not be interested in priority of an already scheduled insn. */ gcc_assert (QUEUE_INDEX (insn) != QUEUE_SCHEDULED); if (!INSN_PRIORITY_KNOWN (insn)) { int this_priority = 0; if (sd_lists_empty_p (insn, SD_LIST_FORW)) /* ??? We should set INSN_PRIORITY to insn_cost when and insn has some forward deps but all of them are ignored by contributes_to_priority hook. At the moment we set priority of such insn to 0. */ this_priority = insn_cost (insn); else { rtx prev_first, twin; basic_block rec; /* For recovery check instructions we calculate priority slightly different than that of normal instructions. Instead of walking through INSN_FORW_DEPS (check) list, we walk through INSN_FORW_DEPS list of each instruction in the corresponding recovery block. */ rec = RECOVERY_BLOCK (insn); if (!rec || rec == EXIT_BLOCK_PTR) { prev_first = PREV_INSN (insn); twin = insn; } else { prev_first = NEXT_INSN (BB_HEAD (rec)); twin = PREV_INSN (BB_END (rec)); } do { sd_iterator_def sd_it; dep_t dep; FOR_EACH_DEP (twin, SD_LIST_FORW, sd_it, dep) { rtx next; int next_priority; next = DEP_CON (dep); if (BLOCK_FOR_INSN (next) != rec) { int cost; if (!contributes_to_priority_p (dep)) continue; if (twin == insn) cost = dep_cost (dep); else { struct _dep _dep1, *dep1 = &_dep1; init_dep (dep1, insn, next, REG_DEP_ANTI); cost = dep_cost (dep1); } next_priority = cost + priority (next); if (next_priority > this_priority) this_priority = next_priority; } } twin = PREV_INSN (twin); } while (twin != prev_first); } INSN_PRIORITY (insn) = this_priority; INSN_PRIORITY_STATUS (insn) = 1; } return INSN_PRIORITY (insn); } /* Macros and functions for keeping the priority queue sorted, and dealing with queuing and dequeuing of instructions. */ #define SCHED_SORT(READY, N_READY) \ do { if ((N_READY) == 2) \ swap_sort (READY, N_READY); \ else if ((N_READY) > 2) \ qsort (READY, N_READY, sizeof (rtx), rank_for_schedule); } \ while (0) /* Returns a positive value if x is preferred; returns a negative value if y is preferred. Should never return 0, since that will make the sort unstable. */ static int rank_for_schedule (const void *x, const void *y) { rtx tmp = *(const rtx *) y; rtx tmp2 = *(const rtx *) x; int tmp_class, tmp2_class; int val, priority_val, weight_val, info_val; /* The insn in a schedule group should be issued the first. */ if (SCHED_GROUP_P (tmp) != SCHED_GROUP_P (tmp2)) return SCHED_GROUP_P (tmp2) ? 1 : -1; /* Make sure that priority of TMP and TMP2 are initialized. */ gcc_assert (INSN_PRIORITY_KNOWN (tmp) && INSN_PRIORITY_KNOWN (tmp2)); /* Prefer insn with higher priority. */ priority_val = INSN_PRIORITY (tmp2) - INSN_PRIORITY (tmp); if (priority_val) return priority_val; /* Prefer speculative insn with greater dependencies weakness. */ if (spec_info) { ds_t ds1, ds2; dw_t dw1, dw2; int dw; ds1 = TODO_SPEC (tmp) & SPECULATIVE; if (ds1) dw1 = dep_weak (ds1); else dw1 = NO_DEP_WEAK; ds2 = TODO_SPEC (tmp2) & SPECULATIVE; if (ds2) dw2 = dep_weak (ds2); else dw2 = NO_DEP_WEAK; dw = dw2 - dw1; if (dw > (NO_DEP_WEAK / 8) || dw < -(NO_DEP_WEAK / 8)) return dw; } /* Prefer an insn with smaller contribution to registers-pressure. */ if (!reload_completed && (weight_val = INSN_REG_WEIGHT (tmp) - INSN_REG_WEIGHT (tmp2))) return weight_val; info_val = (*current_sched_info->rank) (tmp, tmp2); if (info_val) return info_val; /* Compare insns based on their relation to the last-scheduled-insn. */ if (INSN_P (last_scheduled_insn)) { dep_t dep1; dep_t dep2; /* Classify the instructions into three classes: 1) Data dependent on last schedule insn. 2) Anti/Output dependent on last scheduled insn. 3) Independent of last scheduled insn, or has latency of one. Choose the insn from the highest numbered class if different. */ dep1 = sd_find_dep_between (last_scheduled_insn, tmp, true); if (dep1 == NULL || dep_cost (dep1) == 1) tmp_class = 3; else if (/* Data dependence. */ DEP_TYPE (dep1) == REG_DEP_TRUE) tmp_class = 1; else tmp_class = 2; dep2 = sd_find_dep_between (last_scheduled_insn, tmp2, true); if (dep2 == NULL || dep_cost (dep2) == 1) tmp2_class = 3; else if (/* Data dependence. */ DEP_TYPE (dep2) == REG_DEP_TRUE) tmp2_class = 1; else tmp2_class = 2; if ((val = tmp2_class - tmp_class)) return val; } /* Prefer the insn which has more later insns that depend on it. This gives the scheduler more freedom when scheduling later instructions at the expense of added register pressure. */ val = (sd_lists_size (tmp2, SD_LIST_FORW) - sd_lists_size (tmp, SD_LIST_FORW)); if (val != 0) return val; /* If insns are equally good, sort by INSN_LUID (original insn order), so that we make the sort stable. This minimizes instruction movement, thus minimizing sched's effect on debugging and cross-jumping. */ return INSN_LUID (tmp) - INSN_LUID (tmp2); } /* Resort the array A in which only element at index N may be out of order. */ HAIFA_INLINE static void swap_sort (rtx *a, int n) { rtx insn = a[n - 1]; int i = n - 2; while (i >= 0 && rank_for_schedule (a + i, &insn) >= 0) { a[i + 1] = a[i]; i -= 1; } a[i + 1] = insn; } /* Add INSN to the insn queue so that it can be executed at least N_CYCLES after the currently executing insn. Preserve insns chain for debugging purposes. */ HAIFA_INLINE static void queue_insn (rtx insn, int n_cycles) { int next_q = NEXT_Q_AFTER (q_ptr, n_cycles); rtx link = alloc_INSN_LIST (insn, insn_queue[next_q]); gcc_assert (n_cycles <= max_insn_queue_index); insn_queue[next_q] = link; q_size += 1; if (sched_verbose >= 2) { fprintf (sched_dump, ";;\t\tReady-->Q: insn %s: ", (*current_sched_info->print_insn) (insn, 0)); fprintf (sched_dump, "queued for %d cycles.\n", n_cycles); } QUEUE_INDEX (insn) = next_q; } /* Remove INSN from queue. */ static void queue_remove (rtx insn) { gcc_assert (QUEUE_INDEX (insn) >= 0); remove_free_INSN_LIST_elem (insn, &insn_queue[QUEUE_INDEX (insn)]); q_size--; QUEUE_INDEX (insn) = QUEUE_NOWHERE; } /* Return a pointer to the bottom of the ready list, i.e. the insn with the lowest priority. */ HAIFA_INLINE static rtx * ready_lastpos (struct ready_list *ready) { gcc_assert (ready->n_ready >= 1); return ready->vec + ready->first - ready->n_ready + 1; } /* Add an element INSN to the ready list so that it ends up with the lowest/highest priority depending on FIRST_P. */ HAIFA_INLINE static void ready_add (struct ready_list *ready, rtx insn, bool first_p) { if (!first_p) { if (ready->first == ready->n_ready) { memmove (ready->vec + ready->veclen - ready->n_ready, ready_lastpos (ready), ready->n_ready * sizeof (rtx)); ready->first = ready->veclen - 1; } ready->vec[ready->first - ready->n_ready] = insn; } else { if (ready->first == ready->veclen - 1) { if (ready->n_ready) /* ready_lastpos() fails when called with (ready->n_ready == 0). */ memmove (ready->vec + ready->veclen - ready->n_ready - 1, ready_lastpos (ready), ready->n_ready * sizeof (rtx)); ready->first = ready->veclen - 2; } ready->vec[++(ready->first)] = insn; } ready->n_ready++; gcc_assert (QUEUE_INDEX (insn) != QUEUE_READY); QUEUE_INDEX (insn) = QUEUE_READY; } /* Remove the element with the highest priority from the ready list and return it. */ HAIFA_INLINE static rtx ready_remove_first (struct ready_list *ready) { rtx t; gcc_assert (ready->n_ready); t = ready->vec[ready->first--]; ready->n_ready--; /* If the queue becomes empty, reset it. */ if (ready->n_ready == 0) ready->first = ready->veclen - 1; gcc_assert (QUEUE_INDEX (t) == QUEUE_READY); QUEUE_INDEX (t) = QUEUE_NOWHERE; return t; } /* The following code implements multi-pass scheduling for the first cycle. In other words, we will try to choose ready insn which permits to start maximum number of insns on the same cycle. */ /* Return a pointer to the element INDEX from the ready. INDEX for insn with the highest priority is 0, and the lowest priority has N_READY - 1. */ HAIFA_INLINE static rtx ready_element (struct ready_list *ready, int index) { gcc_assert (ready->n_ready && index < ready->n_ready); return ready->vec[ready->first - index]; } /* Remove the element INDEX from the ready list and return it. INDEX for insn with the highest priority is 0, and the lowest priority has N_READY - 1. */ HAIFA_INLINE static rtx ready_remove (struct ready_list *ready, int index) { rtx t; int i; if (index == 0) return ready_remove_first (ready); gcc_assert (ready->n_ready && index < ready->n_ready); t = ready->vec[ready->first - index]; ready->n_ready--; for (i = index; i < ready->n_ready; i++) ready->vec[ready->first - i] = ready->vec[ready->first - i - 1]; QUEUE_INDEX (t) = QUEUE_NOWHERE; return t; } /* Remove INSN from the ready list. */ static void ready_remove_insn (rtx insn) { int i; for (i = 0; i < readyp->n_ready; i++) if (ready_element (readyp, i) == insn) { ready_remove (readyp, i); return; } gcc_unreachable (); } /* Sort the ready list READY by ascending priority, using the SCHED_SORT macro. */ HAIFA_INLINE static void ready_sort (struct ready_list *ready) { rtx *first = ready_lastpos (ready); SCHED_SORT (first, ready->n_ready); } /* PREV is an insn that is ready to execute. Adjust its priority if that will help shorten or lengthen register lifetimes as appropriate. Also provide a hook for the target to tweak itself. */ HAIFA_INLINE static void adjust_priority (rtx prev) { /* ??? There used to be code here to try and estimate how an insn affected register lifetimes, but it did it by looking at REG_DEAD notes, which we removed in schedule_region. Nor did it try to take into account register pressure or anything useful like that. Revisit when we have a machine model to work with and not before. */ if (targetm.sched.adjust_priority) INSN_PRIORITY (prev) = targetm.sched.adjust_priority (prev, INSN_PRIORITY (prev)); } /* Advance time on one cycle. */ HAIFA_INLINE static void advance_one_cycle (void) { if (targetm.sched.dfa_pre_advance_cycle) targetm.sched.dfa_pre_advance_cycle (); if (targetm.sched.dfa_pre_cycle_insn) state_transition (curr_state, targetm.sched.dfa_pre_cycle_insn ()); state_transition (curr_state, NULL); if (targetm.sched.dfa_post_cycle_insn) state_transition (curr_state, targetm.sched.dfa_post_cycle_insn ()); if (targetm.sched.dfa_post_advance_cycle) targetm.sched.dfa_post_advance_cycle (); } /* Clock at which the previous instruction was issued. */ static int last_clock_var; /* INSN is the "currently executing insn". Launch each insn which was waiting on INSN. READY is the ready list which contains the insns that are ready to fire. CLOCK is the current cycle. The function returns necessary cycle advance after issuing the insn (it is not zero for insns in a schedule group). */ static int schedule_insn (rtx insn) { sd_iterator_def sd_it; dep_t dep; int advance = 0; if (sched_verbose >= 1) { char buf[2048]; print_insn (buf, insn, 0); buf[40] = 0; fprintf (sched_dump, ";;\t%3i--> %-40s:", clock_var, buf); if (recog_memoized (insn) < 0) fprintf (sched_dump, "nothing"); else print_reservation (sched_dump, insn); fputc ('\n', sched_dump); } /* Scheduling instruction should have all its dependencies resolved and should have been removed from the ready list. */ gcc_assert (sd_lists_empty_p (insn, SD_LIST_BACK)); gcc_assert (QUEUE_INDEX (insn) == QUEUE_NOWHERE); QUEUE_INDEX (insn) = QUEUE_SCHEDULED; gcc_assert (INSN_TICK (insn) >= MIN_TICK); if (INSN_TICK (insn) > clock_var) /* INSN has been prematurely moved from the queue to the ready list. This is possible only if following flag is set. */ gcc_assert (flag_sched_stalled_insns); /* ??? Probably, if INSN is scheduled prematurely, we should leave INSN_TICK untouched. This is a machine-dependent issue, actually. */ INSN_TICK (insn) = clock_var; /* Update dependent instructions. */ for (sd_it = sd_iterator_start (insn, SD_LIST_FORW); sd_iterator_cond (&sd_it, &dep);) { rtx next = DEP_CON (dep); /* Resolve the dependence between INSN and NEXT. sd_resolve_dep () moves current dep to another list thus advancing the iterator. */ sd_resolve_dep (sd_it); if (!IS_SPECULATION_BRANCHY_CHECK_P (insn)) { int effective_cost; effective_cost = try_ready (next); if (effective_cost >= 0 && SCHED_GROUP_P (next) && advance < effective_cost) advance = effective_cost; } else /* Check always has only one forward dependence (to the first insn in the recovery block), therefore, this will be executed only once. */ { gcc_assert (sd_lists_empty_p (insn, SD_LIST_FORW)); fix_recovery_deps (RECOVERY_BLOCK (insn)); } } /* This is the place where scheduler doesn't *basically* need backward and forward dependencies for INSN anymore. Nevertheless they are used in heuristics in rank_for_schedule (), early_queue_to_ready () and in some targets (e.g. rs6000). Thus the earliest place where we *can* remove dependencies is after targetm.sched.md_finish () call in schedule_block (). But, on the other side, the safest place to remove dependencies is when we are finishing scheduling entire region. As we don't generate [many] dependencies during scheduling itself, we won't need memory until beginning of next region. Bottom line: Dependencies are removed for all insns in the end of scheduling the region. */ /* Annotate the instruction with issue information -- TImode indicates that the instruction is expected not to be able to issue on the same cycle as the previous insn. A machine may use this information to decide how the instruction should be aligned. */ if (issue_rate > 1 && GET_CODE (PATTERN (insn)) != USE && GET_CODE (PATTERN (insn)) != CLOBBER) { if (reload_completed) PUT_MODE (insn, clock_var > last_clock_var ? TImode : VOIDmode); last_clock_var = clock_var; } return advance; } /* Functions for handling of notes. */ /* Delete notes beginning with INSN and put them in the chain of notes ended by NOTE_LIST. Returns the insn following the notes. */ static rtx unlink_other_notes (rtx insn, rtx tail) { rtx prev = PREV_INSN (insn); while (insn != tail && NOTE_NOT_BB_P (insn)) { rtx next = NEXT_INSN (insn); basic_block bb = BLOCK_FOR_INSN (insn); /* Delete the note from its current position. */ if (prev) NEXT_INSN (prev) = next; if (next) PREV_INSN (next) = prev; if (bb) { /* Basic block can begin with either LABEL or NOTE_INSN_BASIC_BLOCK. */ gcc_assert (BB_HEAD (bb) != insn); /* Check if we are removing last insn in the BB. */ if (BB_END (bb) == insn) BB_END (bb) = prev; } /* See sched_analyze to see how these are handled. */ if (NOTE_KIND (insn) != NOTE_INSN_EH_REGION_BEG && NOTE_KIND (insn) != NOTE_INSN_EH_REGION_END) { /* Insert the note at the end of the notes list. */ PREV_INSN (insn) = note_list; if (note_list) NEXT_INSN (note_list) = insn; note_list = insn; } insn = next; } return insn; } /* Return the head and tail pointers of ebb starting at BEG and ending at END. */ void get_ebb_head_tail (basic_block beg, basic_block end, rtx *headp, rtx *tailp) { rtx beg_head = BB_HEAD (beg); rtx beg_tail = BB_END (beg); rtx end_head = BB_HEAD (end); rtx end_tail = BB_END (end); /* Don't include any notes or labels at the beginning of the BEG basic block, or notes at the end of the END basic blocks. */ if (LABEL_P (beg_head)) beg_head = NEXT_INSN (beg_head); while (beg_head != beg_tail) if (NOTE_P (beg_head)) beg_head = NEXT_INSN (beg_head); else break; *headp = beg_head; if (beg == end) end_head = beg_head; else if (LABEL_P (end_head)) end_head = NEXT_INSN (end_head); while (end_head != end_tail) if (NOTE_P (end_tail)) end_tail = PREV_INSN (end_tail); else break; *tailp = end_tail; } /* Return nonzero if there are no real insns in the range [ HEAD, TAIL ]. */ int no_real_insns_p (const_rtx head, const_rtx tail) { while (head != NEXT_INSN (tail)) { if (!NOTE_P (head) && !LABEL_P (head)) return 0; head = NEXT_INSN (head); } return 1; } /* Delete notes between HEAD and TAIL and put them in the chain of notes ended by NOTE_LIST. */ void rm_other_notes (rtx head, rtx tail) { rtx next_tail; rtx insn; note_list = 0; if (head == tail && (! INSN_P (head))) return; next_tail = NEXT_INSN (tail); for (insn = head; insn != next_tail; insn = NEXT_INSN (insn)) { rtx prev; /* Farm out notes, and maybe save them in NOTE_LIST. This is needed to keep the debugger from getting completely deranged. */ if (NOTE_NOT_BB_P (insn)) { prev = insn; insn = unlink_other_notes (insn, next_tail); gcc_assert (prev != tail && prev != head && insn != next_tail); } } } /* Functions for computation of registers live/usage info. */ /* This function looks for a new register being defined. If the destination register is already used by the source, a new register is not needed. */ static int find_set_reg_weight (const_rtx x) { if (GET_CODE (x) == CLOBBER && register_operand (SET_DEST (x), VOIDmode)) return 1; if (GET_CODE (x) == SET && register_operand (SET_DEST (x), VOIDmode)) { if (REG_P (SET_DEST (x))) { if (!reg_mentioned_p (SET_DEST (x), SET_SRC (x))) return 1; else return 0; } return 1; } return 0; } /* Calculate INSN_REG_WEIGHT for all insns of a block. */ static void find_insn_reg_weight (basic_block bb) { rtx insn, next_tail, head, tail; get_ebb_head_tail (bb, bb, &head, &tail); next_tail = NEXT_INSN (tail); for (insn = head; insn != next_tail; insn = NEXT_INSN (insn)) find_insn_reg_weight1 (insn); } /* Calculate INSN_REG_WEIGHT for single instruction. Separated from find_insn_reg_weight because of need to initialize new instruction in generate_recovery_code. */ static void find_insn_reg_weight1 (rtx insn) { int reg_weight = 0; rtx x; /* Handle register life information. */ if (! INSN_P (insn)) return; /* Increment weight for each register born here. */ x = PATTERN (insn); reg_weight += find_set_reg_weight (x); if (GET_CODE (x) == PARALLEL) { int j; for (j = XVECLEN (x, 0) - 1; j >= 0; j--) { x = XVECEXP (PATTERN (insn), 0, j); reg_weight += find_set_reg_weight (x); } } /* Decrement weight for each register that dies here. */ for (x = REG_NOTES (insn); x; x = XEXP (x, 1)) { if (REG_NOTE_KIND (x) == REG_DEAD || REG_NOTE_KIND (x) == REG_UNUSED) reg_weight--; } INSN_REG_WEIGHT (insn) = reg_weight; } /* Move insns that became ready to fire from queue to ready list. */ static void queue_to_ready (struct ready_list *ready) { rtx insn; rtx link; rtx skip_insn; q_ptr = NEXT_Q (q_ptr); if (dbg_cnt (sched_insn) == false) /* If debug counter is activated do not requeue insn next after last_scheduled_insn. */ skip_insn = next_nonnote_insn (last_scheduled_insn); else skip_insn = NULL_RTX; /* Add all pending insns that can be scheduled without stalls to the ready list. */ for (link = insn_queue[q_ptr]; link; link = XEXP (link, 1)) { insn = XEXP (link, 0); q_size -= 1; if (sched_verbose >= 2) fprintf (sched_dump, ";;\t\tQ-->Ready: insn %s: ", (*current_sched_info->print_insn) (insn, 0)); /* If the ready list is full, delay the insn for 1 cycle. See the comment in schedule_block for the rationale. */ if (!reload_completed && ready->n_ready > MAX_SCHED_READY_INSNS && !SCHED_GROUP_P (insn) && insn != skip_insn) { if (sched_verbose >= 2) fprintf (sched_dump, "requeued because ready full\n"); queue_insn (insn, 1); } else { ready_add (ready, insn, false); if (sched_verbose >= 2) fprintf (sched_dump, "moving to ready without stalls\n"); } } free_INSN_LIST_list (&insn_queue[q_ptr]); /* If there are no ready insns, stall until one is ready and add all of the pending insns at that point to the ready list. */ if (ready->n_ready == 0) { int stalls; for (stalls = 1; stalls <= max_insn_queue_index; stalls++) { if ((link = insn_queue[NEXT_Q_AFTER (q_ptr, stalls)])) { for (; link; link = XEXP (link, 1)) { insn = XEXP (link, 0); q_size -= 1; if (sched_verbose >= 2) fprintf (sched_dump, ";;\t\tQ-->Ready: insn %s: ", (*current_sched_info->print_insn) (insn, 0)); ready_add (ready, insn, false); if (sched_verbose >= 2) fprintf (sched_dump, "moving to ready with %d stalls\n", stalls); } free_INSN_LIST_list (&insn_queue[NEXT_Q_AFTER (q_ptr, stalls)]); advance_one_cycle (); break; } advance_one_cycle (); } q_ptr = NEXT_Q_AFTER (q_ptr, stalls); clock_var += stalls; } } /* Used by early_queue_to_ready. Determines whether it is "ok" to prematurely move INSN from the queue to the ready list. Currently, if a target defines the hook 'is_costly_dependence', this function uses the hook to check whether there exist any dependences which are considered costly by the target, between INSN and other insns that have already been scheduled. Dependences are checked up to Y cycles back, with default Y=1; The flag -fsched-stalled-insns-dep=Y allows controlling this value. (Other considerations could be taken into account instead (or in addition) depending on user flags and target hooks. */ static bool ok_for_early_queue_removal (rtx insn) { int n_cycles; rtx prev_insn = last_scheduled_insn; if (targetm.sched.is_costly_dependence) { for (n_cycles = flag_sched_stalled_insns_dep; n_cycles; n_cycles--) { for ( ; prev_insn; prev_insn = PREV_INSN (prev_insn)) { int cost; if (prev_insn == current_sched_info->prev_head) { prev_insn = NULL; break; } if (!NOTE_P (prev_insn)) { dep_t dep; dep = sd_find_dep_between (prev_insn, insn, true); if (dep != NULL) { cost = dep_cost (dep); if (targetm.sched.is_costly_dependence (dep, cost, flag_sched_stalled_insns_dep - n_cycles)) return false; } } if (GET_MODE (prev_insn) == TImode) /* end of dispatch group */ break; } if (!prev_insn) break; prev_insn = PREV_INSN (prev_insn); } } return true; } /* Remove insns from the queue, before they become "ready" with respect to FU latency considerations. */ static int early_queue_to_ready (state_t state, struct ready_list *ready) { rtx insn; rtx link; rtx next_link; rtx prev_link; bool move_to_ready; int cost; state_t temp_state = alloca (dfa_state_size); int stalls; int insns_removed = 0; /* Flag '-fsched-stalled-insns=X' determines the aggressiveness of this function: X == 0: There is no limit on how many queued insns can be removed prematurely. (flag_sched_stalled_insns = -1). X >= 1: Only X queued insns can be removed prematurely in each invocation. (flag_sched_stalled_insns = X). Otherwise: Early queue removal is disabled. (flag_sched_stalled_insns = 0) */ if (! flag_sched_stalled_insns) return 0; for (stalls = 0; stalls <= max_insn_queue_index; stalls++) { if ((link = insn_queue[NEXT_Q_AFTER (q_ptr, stalls)])) { if (sched_verbose > 6) fprintf (sched_dump, ";; look at index %d + %d\n", q_ptr, stalls); prev_link = 0; while (link) { next_link = XEXP (link, 1); insn = XEXP (link, 0); if (insn && sched_verbose > 6) print_rtl_single (sched_dump, insn); memcpy (temp_state, state, dfa_state_size); if (recog_memoized (insn) < 0) /* non-negative to indicate that it's not ready to avoid infinite Q->R->Q->R... */ cost = 0; else cost = state_transition (temp_state, insn); if (sched_verbose >= 6) fprintf (sched_dump, "transition cost = %d\n", cost); move_to_ready = false; if (cost < 0) { move_to_ready = ok_for_early_queue_removal (insn); if (move_to_ready == true) { /* move from Q to R */ q_size -= 1; ready_add (ready, insn, false); if (prev_link) XEXP (prev_link, 1) = next_link; else insn_queue[NEXT_Q_AFTER (q_ptr, stalls)] = next_link; free_INSN_LIST_node (link); if (sched_verbose >= 2) fprintf (sched_dump, ";;\t\tEarly Q-->Ready: insn %s\n", (*current_sched_info->print_insn) (insn, 0)); insns_removed++; if (insns_removed == flag_sched_stalled_insns) /* Remove no more than flag_sched_stalled_insns insns from Q at a time. */ return insns_removed; } } if (move_to_ready == false) prev_link = link; link = next_link; } /* while link */ } /* if link */ } /* for stalls.. */ return insns_removed; } /* Print the ready list for debugging purposes. Callable from debugger. */ static void debug_ready_list (struct ready_list *ready) { rtx *p; int i; if (ready->n_ready == 0) { fprintf (sched_dump, "\n"); return; } p = ready_lastpos (ready); for (i = 0; i < ready->n_ready; i++) fprintf (sched_dump, " %s", (*current_sched_info->print_insn) (p[i], 0)); fprintf (sched_dump, "\n"); } /* Search INSN for REG_SAVE_NOTE note pairs for NOTE_INSN_EHREGION_{BEG,END}; and convert them back into NOTEs. The REG_SAVE_NOTE note following first one is contains the saved value for NOTE_BLOCK_NUMBER which is useful for NOTE_INSN_EH_REGION_{BEG,END} NOTEs. */ static void reemit_notes (rtx insn) { rtx note, last = insn; for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) { if (REG_NOTE_KIND (note) == REG_SAVE_NOTE) { enum insn_note note_type = INTVAL (XEXP (note, 0)); last = emit_note_before (note_type, last); remove_note (insn, note); } } } /* Move INSN. Reemit notes if needed. Update CFG, if needed. */ static void move_insn (rtx insn) { rtx last = last_scheduled_insn; if (PREV_INSN (insn) != last) { basic_block bb; rtx note; int jump_p = 0; bb = BLOCK_FOR_INSN (insn); /* BB_HEAD is either LABEL or NOTE. */ gcc_assert (BB_HEAD (bb) != insn); if (BB_END (bb) == insn) /* If this is last instruction in BB, move end marker one instruction up. */ { /* Jumps are always placed at the end of basic block. */ jump_p = control_flow_insn_p (insn); gcc_assert (!jump_p || ((current_sched_info->flags & SCHED_RGN) && IS_SPECULATION_BRANCHY_CHECK_P (insn)) || (current_sched_info->flags & SCHED_EBB)); gcc_assert (BLOCK_FOR_INSN (PREV_INSN (insn)) == bb); BB_END (bb) = PREV_INSN (insn); } gcc_assert (BB_END (bb) != last); if (jump_p) /* We move the block note along with jump. */ { /* NT is needed for assertion below. */ rtx nt = current_sched_info->next_tail; note = NEXT_INSN (insn); while (NOTE_NOT_BB_P (note) && note != nt) note = NEXT_INSN (note); if (note != nt && (LABEL_P (note) || BARRIER_P (note))) note = NEXT_INSN (note); gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); } else note = insn; NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (note); PREV_INSN (NEXT_INSN (note)) = PREV_INSN (insn); NEXT_INSN (note) = NEXT_INSN (last); PREV_INSN (NEXT_INSN (last)) = note; NEXT_INSN (last) = insn; PREV_INSN (insn) = last; bb = BLOCK_FOR_INSN (last); if (jump_p) { fix_jump_move (insn); if (BLOCK_FOR_INSN (insn) != bb) move_block_after_check (insn); gcc_assert (BB_END (bb) == last); } df_insn_change_bb (insn, bb); /* Update BB_END, if needed. */ if (BB_END (bb) == last) BB_END (bb) = insn; } reemit_notes (insn); SCHED_GROUP_P (insn) = 0; } /* The following structure describe an entry of the stack of choices. */ struct choice_entry { /* Ordinal number of the issued insn in the ready queue. */ int index; /* The number of the rest insns whose issues we should try. */ int rest; /* The number of issued essential insns. */ int n; /* State after issuing the insn. */ state_t state; }; /* The following array is used to implement a stack of choices used in function max_issue. */ static struct choice_entry *choice_stack; /* The following variable value is number of essential insns issued on the current cycle. An insn is essential one if it changes the processors state. */ static int cycle_issued_insns; /* The following variable value is maximal number of tries of issuing insns for the first cycle multipass insn scheduling. We define this value as constant*(DFA_LOOKAHEAD**ISSUE_RATE). We would not need this constraint if all real insns (with non-negative codes) had reservations because in this case the algorithm complexity is O(DFA_LOOKAHEAD**ISSUE_RATE). Unfortunately, the dfa descriptions might be incomplete and such insn might occur. For such descriptions, the complexity of algorithm (without the constraint) could achieve DFA_LOOKAHEAD ** N , where N is the queue length. */ static int max_lookahead_tries; /* The following value is value of hook `first_cycle_multipass_dfa_lookahead' at the last call of `max_issue'. */ static int cached_first_cycle_multipass_dfa_lookahead = 0; /* The following value is value of `issue_rate' at the last call of `sched_init'. */ static int cached_issue_rate = 0; /* The following function returns maximal (or close to maximal) number of insns which can be issued on the same cycle and one of which insns is insns with the best rank (the first insn in READY). To make this function tries different samples of ready insns. READY is current queue `ready'. Global array READY_TRY reflects what insns are already issued in this try. MAX_POINTS is the sum of points of all instructions in READY. The function stops immediately, if it reached the such a solution, that all instruction can be issued. INDEX will contain index of the best insn in READY. The following function is used only for first cycle multipass scheduling. */ static int max_issue (struct ready_list *ready, int *index, int max_points) { int n, i, all, n_ready, best, delay, tries_num, points = -1; struct choice_entry *top; rtx insn; best = 0; memcpy (choice_stack->state, curr_state, dfa_state_size); top = choice_stack; top->rest = cached_first_cycle_multipass_dfa_lookahead; top->n = 0; n_ready = ready->n_ready; for (all = i = 0; i < n_ready; i++) if (!ready_try [i]) all++; i = 0; tries_num = 0; for (;;) { if (top->rest == 0 || i >= n_ready) { if (top == choice_stack) break; if (best < top - choice_stack && ready_try [0]) { best = top - choice_stack; *index = choice_stack [1].index; points = top->n; if (top->n == max_points || best == all) break; } i = top->index; ready_try [i] = 0; top--; memcpy (curr_state, top->state, dfa_state_size); } else if (!ready_try [i]) { tries_num++; if (tries_num > max_lookahead_tries) break; insn = ready_element (ready, i); delay = state_transition (curr_state, insn); if (delay < 0) { if (state_dead_lock_p (curr_state)) top->rest = 0; else top->rest--; n = top->n; if (memcmp (top->state, curr_state, dfa_state_size) != 0) n += ISSUE_POINTS (insn); top++; top->rest = cached_first_cycle_multipass_dfa_lookahead; top->index = i; top->n = n; memcpy (top->state, curr_state, dfa_state_size); ready_try [i] = 1; i = -1; } } i++; } while (top != choice_stack) { ready_try [top->index] = 0; top--; } memcpy (curr_state, choice_stack->state, dfa_state_size); if (sched_verbose >= 4) fprintf (sched_dump, ";;\t\tChoosed insn : %s; points: %d/%d\n", (*current_sched_info->print_insn) (ready_element (ready, *index), 0), points, max_points); return best; } /* The following function chooses insn from READY and modifies *N_READY and READY. The following function is used only for first cycle multipass scheduling. Return: -1 if cycle should be advanced, 0 if INSN_PTR is set to point to the desirable insn, 1 if choose_ready () should be restarted without advancing the cycle. */ static int choose_ready (struct ready_list *ready, rtx *insn_ptr) { int lookahead; if (dbg_cnt (sched_insn) == false) { rtx insn; insn = next_nonnote_insn (last_scheduled_insn); if (QUEUE_INDEX (insn) == QUEUE_READY) /* INSN is in the ready_list. */ { ready_remove_insn (insn); *insn_ptr = insn; return 0; } /* INSN is in the queue. Advance cycle to move it to the ready list. */ return -1; } lookahead = 0; if (targetm.sched.first_cycle_multipass_dfa_lookahead) lookahead = targetm.sched.first_cycle_multipass_dfa_lookahead (); if (lookahead <= 0 || SCHED_GROUP_P (ready_element (ready, 0))) { *insn_ptr = ready_remove_first (ready); return 0; } else { /* Try to choose the better insn. */ int index = 0, i, n; rtx insn; int more_issue, max_points, try_data = 1, try_control = 1; if (cached_first_cycle_multipass_dfa_lookahead != lookahead) { cached_first_cycle_multipass_dfa_lookahead = lookahead; max_lookahead_tries = 100; for (i = 0; i < issue_rate; i++) max_lookahead_tries *= lookahead; } insn = ready_element (ready, 0); if (INSN_CODE (insn) < 0) { *insn_ptr = ready_remove_first (ready); return 0; } if (spec_info && spec_info->flags & (PREFER_NON_DATA_SPEC | PREFER_NON_CONTROL_SPEC)) { for (i = 0, n = ready->n_ready; i < n; i++) { rtx x; ds_t s; x = ready_element (ready, i); s = TODO_SPEC (x); if (spec_info->flags & PREFER_NON_DATA_SPEC && !(s & DATA_SPEC)) { try_data = 0; if (!(spec_info->flags & PREFER_NON_CONTROL_SPEC) || !try_control) break; } if (spec_info->flags & PREFER_NON_CONTROL_SPEC && !(s & CONTROL_SPEC)) { try_control = 0; if (!(spec_info->flags & PREFER_NON_DATA_SPEC) || !try_data) break; } } } if ((!try_data && (TODO_SPEC (insn) & DATA_SPEC)) || (!try_control && (TODO_SPEC (insn) & CONTROL_SPEC)) || (targetm.sched.first_cycle_multipass_dfa_lookahead_guard_spec && !targetm.sched.first_cycle_multipass_dfa_lookahead_guard_spec (insn))) /* Discard speculative instruction that stands first in the ready list. */ { change_queue_index (insn, 1); return 1; } max_points = ISSUE_POINTS (insn); more_issue = issue_rate - cycle_issued_insns - 1; for (i = 1; i < ready->n_ready; i++) { insn = ready_element (ready, i); ready_try [i] = (INSN_CODE (insn) < 0 || (!try_data && (TODO_SPEC (insn) & DATA_SPEC)) || (!try_control && (TODO_SPEC (insn) & CONTROL_SPEC)) || (targetm.sched.first_cycle_multipass_dfa_lookahead_guard && !targetm.sched.first_cycle_multipass_dfa_lookahead_guard (insn))); if (!ready_try [i] && more_issue-- > 0) max_points += ISSUE_POINTS (insn); } if (max_issue (ready, &index, max_points) == 0) { *insn_ptr = ready_remove_first (ready); return 0; } else { *insn_ptr = ready_remove (ready, index); return 0; } } } /* Use forward list scheduling to rearrange insns of block pointed to by TARGET_BB, possibly bringing insns from subsequent blocks in the same region. */ void schedule_block (basic_block *target_bb, int rgn_n_insns1) { struct ready_list ready; int i, first_cycle_insn_p; int can_issue_more; state_t temp_state = NULL; /* It is used for multipass scheduling. */ int sort_p, advance, start_clock_var; /* Head/tail info for this block. */ rtx prev_head = current_sched_info->prev_head; rtx next_tail = current_sched_info->next_tail; rtx head = NEXT_INSN (prev_head); rtx tail = PREV_INSN (next_tail); /* We used to have code to avoid getting parameters moved from hard argument registers into pseudos. However, it was removed when it proved to be of marginal benefit and caused problems because schedule_block and compute_forward_dependences had different notions of what the "head" insn was. */ gcc_assert (head != tail || INSN_P (head)); haifa_recovery_bb_recently_added_p = false; /* Debug info. */ if (sched_verbose) dump_new_block_header (0, *target_bb, head, tail); state_reset (curr_state); /* Allocate the ready list. */ readyp = &ready; ready.vec = NULL; ready_try = NULL; choice_stack = NULL; rgn_n_insns = -1; extend_ready (rgn_n_insns1 + 1); ready.first = ready.veclen - 1; ready.n_ready = 0; /* It is used for first cycle multipass scheduling. */ temp_state = alloca (dfa_state_size); if (targetm.sched.md_init) targetm.sched.md_init (sched_dump, sched_verbose, ready.veclen); /* We start inserting insns after PREV_HEAD. */ last_scheduled_insn = prev_head; gcc_assert (NOTE_P (last_scheduled_insn) && BLOCK_FOR_INSN (last_scheduled_insn) == *target_bb); /* Initialize INSN_QUEUE. Q_SIZE is the total number of insns in the queue. */ q_ptr = 0; q_size = 0; insn_queue = alloca ((max_insn_queue_index + 1) * sizeof (rtx)); memset (insn_queue, 0, (max_insn_queue_index + 1) * sizeof (rtx)); /* Start just before the beginning of time. */ clock_var = -1; /* We need queue and ready lists and clock_var be initialized in try_ready () (which is called through init_ready_list ()). */ (*current_sched_info->init_ready_list) (); /* The algorithm is O(n^2) in the number of ready insns at any given time in the worst case. Before reload we are more likely to have big lists so truncate them to a reasonable size. */ if (!reload_completed && ready.n_ready > MAX_SCHED_READY_INSNS) { ready_sort (&ready); /* Find first free-standing insn past MAX_SCHED_READY_INSNS. */ for (i = MAX_SCHED_READY_INSNS; i < ready.n_ready; i++) if (!SCHED_GROUP_P (ready_element (&ready, i))) break; if (sched_verbose >= 2) { fprintf (sched_dump, ";;\t\tReady list on entry: %d insns\n", ready.n_ready); fprintf (sched_dump, ";;\t\t before reload => truncated to %d insns\n", i); } /* Delay all insns past it for 1 cycle. If debug counter is activated make an exception for the insn right after last_scheduled_insn. */ { rtx skip_insn; if (dbg_cnt (sched_insn) == false) skip_insn = next_nonnote_insn (last_scheduled_insn); else skip_insn = NULL_RTX; while (i < ready.n_ready) { rtx insn; insn = ready_remove (&ready, i); if (insn != skip_insn) queue_insn (insn, 1); } } } /* Now we can restore basic block notes and maintain precise cfg. */ restore_bb_notes (*target_bb); last_clock_var = -1; advance = 0; sort_p = TRUE; /* Loop until all the insns in BB are scheduled. */ while ((*current_sched_info->schedule_more_p) ()) { do { start_clock_var = clock_var; clock_var++; advance_one_cycle (); /* Add to the ready list all pending insns that can be issued now. If there are no ready insns, increment clock until one is ready and add all pending insns at that point to the ready list. */ queue_to_ready (&ready); gcc_assert (ready.n_ready); if (sched_verbose >= 2) { fprintf (sched_dump, ";;\t\tReady list after queue_to_ready: "); debug_ready_list (&ready); } advance -= clock_var - start_clock_var; } while (advance > 0); if (sort_p) { /* Sort the ready list based on priority. */ ready_sort (&ready); if (sched_verbose >= 2) { fprintf (sched_dump, ";;\t\tReady list after ready_sort: "); debug_ready_list (&ready); } } /* Allow the target to reorder the list, typically for better instruction bundling. */ if (sort_p && targetm.sched.reorder && (ready.n_ready == 0 || !SCHED_GROUP_P (ready_element (&ready, 0)))) can_issue_more = targetm.sched.reorder (sched_dump, sched_verbose, ready_lastpos (&ready), &ready.n_ready, clock_var); else can_issue_more = issue_rate; first_cycle_insn_p = 1; cycle_issued_insns = 0; for (;;) { rtx insn; int cost; bool asm_p = false; if (sched_verbose >= 2) { fprintf (sched_dump, ";;\tReady list (t = %3d): ", clock_var); debug_ready_list (&ready); } if (ready.n_ready == 0 && can_issue_more && reload_completed) { /* Allow scheduling insns directly from the queue in case there's nothing better to do (ready list is empty) but there are still vacant dispatch slots in the current cycle. */ if (sched_verbose >= 6) fprintf (sched_dump,";;\t\tSecond chance\n"); memcpy (temp_state, curr_state, dfa_state_size); if (early_queue_to_ready (temp_state, &ready)) ready_sort (&ready); } if (ready.n_ready == 0 || !can_issue_more || state_dead_lock_p (curr_state) || !(*current_sched_info->schedule_more_p) ()) break; /* Select and remove the insn from the ready list. */ if (sort_p) { int res; insn = NULL_RTX; res = choose_ready (&ready, &insn); if (res < 0) /* Finish cycle. */ break; if (res > 0) /* Restart choose_ready (). */ continue; gcc_assert (insn != NULL_RTX); } else insn = ready_remove_first (&ready); if (targetm.sched.dfa_new_cycle && targetm.sched.dfa_new_cycle (sched_dump, sched_verbose, insn, last_clock_var, clock_var, &sort_p)) /* SORT_P is used by the target to override sorting of the ready list. This is needed when the target has modified its internal structures expecting that the insn will be issued next. As we need the insn to have the highest priority (so it will be returned by the ready_remove_first call above), we invoke ready_add (&ready, insn, true). But, still, there is one issue: INSN can be later discarded by scheduler's front end through current_sched_info->can_schedule_ready_p, hence, won't be issued next. */ { ready_add (&ready, insn, true); break; } sort_p = TRUE; memcpy (temp_state, curr_state, dfa_state_size); if (recog_memoized (insn) < 0) { asm_p = (GET_CODE (PATTERN (insn)) == ASM_INPUT || asm_noperands (PATTERN (insn)) >= 0); if (!first_cycle_insn_p && asm_p) /* This is asm insn which is tried to be issued on the cycle not first. Issue it on the next cycle. */ cost = 1; else /* A USE insn, or something else we don't need to understand. We can't pass these directly to state_transition because it will trigger a fatal error for unrecognizable insns. */ cost = 0; } else { cost = state_transition (temp_state, insn); if (cost < 0) cost = 0; else if (cost == 0) cost = 1; } if (cost >= 1) { queue_insn (insn, cost); if (SCHED_GROUP_P (insn)) { advance = cost; break; } continue; } if (current_sched_info->can_schedule_ready_p && ! (*current_sched_info->can_schedule_ready_p) (insn)) /* We normally get here only if we don't want to move insn from the split block. */ { TODO_SPEC (insn) = (TODO_SPEC (insn) & ~SPECULATIVE) | HARD_DEP; continue; } /* DECISION is made. */ if (TODO_SPEC (insn) & SPECULATIVE) generate_recovery_code (insn); if (control_flow_insn_p (last_scheduled_insn) /* This is used to switch basic blocks by request from scheduler front-end (actually, sched-ebb.c only). This is used to process blocks with single fallthru edge. If succeeding block has jump, it [jump] will try move at the end of current bb, thus corrupting CFG. */ || current_sched_info->advance_target_bb (*target_bb, insn)) { *target_bb = current_sched_info->advance_target_bb (*target_bb, 0); if (sched_verbose) { rtx x; x = next_real_insn (last_scheduled_insn); gcc_assert (x); dump_new_block_header (1, *target_bb, x, tail); } last_scheduled_insn = bb_note (*target_bb); } /* Update counters, etc in the scheduler's front end. */ (*current_sched_info->begin_schedule_ready) (insn, last_scheduled_insn); move_insn (insn); last_scheduled_insn = insn; if (memcmp (curr_state, temp_state, dfa_state_size) != 0) { cycle_issued_insns++; memcpy (curr_state, temp_state, dfa_state_size); } if (targetm.sched.variable_issue) can_issue_more = targetm.sched.variable_issue (sched_dump, sched_verbose, insn, can_issue_more); /* A naked CLOBBER or USE generates no instruction, so do not count them against the issue rate. */ else if (GET_CODE (PATTERN (insn)) != USE && GET_CODE (PATTERN (insn)) != CLOBBER) can_issue_more--; advance = schedule_insn (insn); /* After issuing an asm insn we should start a new cycle. */ if (advance == 0 && asm_p) advance = 1; if (advance != 0) break; first_cycle_insn_p = 0; /* Sort the ready list based on priority. This must be redone here, as schedule_insn may have readied additional insns that will not be sorted correctly. */ if (ready.n_ready > 0) ready_sort (&ready); if (targetm.sched.reorder2 && (ready.n_ready == 0 || !SCHED_GROUP_P (ready_element (&ready, 0)))) { can_issue_more = targetm.sched.reorder2 (sched_dump, sched_verbose, ready.n_ready ? ready_lastpos (&ready) : NULL, &ready.n_ready, clock_var); } } } /* Debug info. */ if (sched_verbose) { fprintf (sched_dump, ";;\tReady list (final): "); debug_ready_list (&ready); } if (current_sched_info->queue_must_finish_empty) /* Sanity check -- queue must be empty now. Meaningless if region has multiple bbs. */ gcc_assert (!q_size && !ready.n_ready); else { /* We must maintain QUEUE_INDEX between blocks in region. */ for (i = ready.n_ready - 1; i >= 0; i--) { rtx x; x = ready_element (&ready, i); QUEUE_INDEX (x) = QUEUE_NOWHERE; TODO_SPEC (x) = (TODO_SPEC (x) & ~SPECULATIVE) | HARD_DEP; } if (q_size) for (i = 0; i <= max_insn_queue_index; i++) { rtx link; for (link = insn_queue[i]; link; link = XEXP (link, 1)) { rtx x; x = XEXP (link, 0); QUEUE_INDEX (x) = QUEUE_NOWHERE; TODO_SPEC (x) = (TODO_SPEC (x) & ~SPECULATIVE) | HARD_DEP; } free_INSN_LIST_list (&insn_queue[i]); } } if (!current_sched_info->queue_must_finish_empty || haifa_recovery_bb_recently_added_p) { /* INSN_TICK (minimum clock tick at which the insn becomes ready) may be not correct for the insn in the subsequent blocks of the region. We should use a correct value of `clock_var' or modify INSN_TICK. It is better to keep clock_var value equal to 0 at the start of a basic block. Therefore we modify INSN_TICK here. */ fix_inter_tick (NEXT_INSN (prev_head), last_scheduled_insn); } if (targetm.sched.md_finish) { targetm.sched.md_finish (sched_dump, sched_verbose); /* Target might have added some instructions to the scheduled block in its md_finish () hook. These new insns don't have any data initialized and to identify them we extend h_i_d so that they'll get zero luids.*/ extend_h_i_d (); } /* Update head/tail boundaries. */ head = NEXT_INSN (prev_head); tail = last_scheduled_insn; /* Restore-other-notes: NOTE_LIST is the end of a chain of notes previously found among the insns. Insert them at the beginning of the insns. */ if (note_list != 0) { basic_block head_bb = BLOCK_FOR_INSN (head); rtx note_head = note_list; while (PREV_INSN (note_head)) { set_block_for_insn (note_head, head_bb); note_head = PREV_INSN (note_head); } /* In the above cycle we've missed this note: */ set_block_for_insn (note_head, head_bb); PREV_INSN (note_head) = PREV_INSN (head); NEXT_INSN (PREV_INSN (head)) = note_head; PREV_INSN (head) = note_list; NEXT_INSN (note_list) = head; head = note_head; } /* Debugging. */ if (sched_verbose) { fprintf (sched_dump, ";; total time = %d\n;; new head = %d\n", clock_var, INSN_UID (head)); fprintf (sched_dump, ";; new tail = %d\n\n", INSN_UID (tail)); } current_sched_info->head = head; current_sched_info->tail = tail; free (ready.vec); free (ready_try); for (i = 0; i <= rgn_n_insns; i++) free (choice_stack [i].state); free (choice_stack); } /* Set_priorities: compute priority of each insn in the block. */ int set_priorities (rtx head, rtx tail) { rtx insn; int n_insn; int sched_max_insns_priority = current_sched_info->sched_max_insns_priority; rtx prev_head; if (head == tail && (! INSN_P (head))) return 0; n_insn = 0; prev_head = PREV_INSN (head); for (insn = tail; insn != prev_head; insn = PREV_INSN (insn)) { if (!INSN_P (insn)) continue; n_insn++; (void) priority (insn); gcc_assert (INSN_PRIORITY_KNOWN (insn)); sched_max_insns_priority = MAX (sched_max_insns_priority, INSN_PRIORITY (insn)); } current_sched_info->sched_max_insns_priority = sched_max_insns_priority; return n_insn; } /* Next LUID to assign to an instruction. */ static int luid; /* Initialize some global state for the scheduler. */ void sched_init (void) { basic_block b; rtx insn; int i; /* Switch to working copy of sched_info. */ memcpy (¤t_sched_info_var, current_sched_info, sizeof (current_sched_info_var)); current_sched_info = ¤t_sched_info_var; /* Disable speculative loads in their presence if cc0 defined. */ #ifdef HAVE_cc0 flag_schedule_speculative_load = 0; #endif /* Set dump and sched_verbose for the desired debugging output. If no dump-file was specified, but -fsched-verbose=N (any N), print to stderr. For -fsched-verbose=N, N>=10, print everything to stderr. */ sched_verbose = sched_verbose_param; if (sched_verbose_param == 0 && dump_file) sched_verbose = 1; sched_dump = ((sched_verbose_param >= 10 || !dump_file) ? stderr : dump_file); /* Initialize SPEC_INFO. */ if (targetm.sched.set_sched_flags) { spec_info = &spec_info_var; targetm.sched.set_sched_flags (spec_info); if (current_sched_info->flags & DO_SPECULATION) spec_info->weakness_cutoff = (PARAM_VALUE (PARAM_SCHED_SPEC_PROB_CUTOFF) * MAX_DEP_WEAK) / 100; else /* So we won't read anything accidentally. */ spec_info = 0; } else /* So we won't read anything accidentally. */ spec_info = 0; /* Initialize issue_rate. */ if (targetm.sched.issue_rate) issue_rate = targetm.sched.issue_rate (); else issue_rate = 1; if (cached_issue_rate != issue_rate) { cached_issue_rate = issue_rate; /* To invalidate max_lookahead_tries: */ cached_first_cycle_multipass_dfa_lookahead = 0; } old_max_uid = 0; h_i_d = 0; extend_h_i_d (); for (i = 0; i < old_max_uid; i++) { h_i_d[i].cost = -1; h_i_d[i].todo_spec = HARD_DEP; h_i_d[i].queue_index = QUEUE_NOWHERE; h_i_d[i].tick = INVALID_TICK; h_i_d[i].inter_tick = INVALID_TICK; } if (targetm.sched.init_dfa_pre_cycle_insn) targetm.sched.init_dfa_pre_cycle_insn (); if (targetm.sched.init_dfa_post_cycle_insn) targetm.sched.init_dfa_post_cycle_insn (); dfa_start (); dfa_state_size = state_size (); curr_state = xmalloc (dfa_state_size); h_i_d[0].luid = 0; luid = 1; FOR_EACH_BB (b) for (insn = BB_HEAD (b); ; insn = NEXT_INSN (insn)) { INSN_LUID (insn) = luid; /* Increment the next luid, unless this is a note. We don't really need separate IDs for notes and we don't want to schedule differently depending on whether or not there are line-number notes, i.e., depending on whether or not we're generating debugging information. */ if (!NOTE_P (insn)) ++luid; if (insn == BB_END (b)) break; } init_dependency_caches (luid); init_alias_analysis (); old_last_basic_block = 0; extend_bb (); /* Compute INSN_REG_WEIGHT for all blocks. We must do this before removing death notes. */ FOR_EACH_BB_REVERSE (b) find_insn_reg_weight (b); if (targetm.sched.md_init_global) targetm.sched.md_init_global (sched_dump, sched_verbose, old_max_uid); nr_begin_data = nr_begin_control = nr_be_in_data = nr_be_in_control = 0; before_recovery = 0; haifa_recovery_bb_ever_added_p = false; #ifdef ENABLE_CHECKING /* This is used preferably for finding bugs in check_cfg () itself. */ check_cfg (0, 0); #endif } /* Free global data used during insn scheduling. */ void sched_finish (void) { free (h_i_d); free (curr_state); dfa_finish (); free_dependency_caches (); end_alias_analysis (); if (targetm.sched.md_finish_global) targetm.sched.md_finish_global (sched_dump, sched_verbose); if (spec_info && spec_info->dump) { char c = reload_completed ? 'a' : 'b'; fprintf (spec_info->dump, ";; %s:\n", current_function_name ()); fprintf (spec_info->dump, ";; Procedure %cr-begin-data-spec motions == %d\n", c, nr_begin_data); fprintf (spec_info->dump, ";; Procedure %cr-be-in-data-spec motions == %d\n", c, nr_be_in_data); fprintf (spec_info->dump, ";; Procedure %cr-begin-control-spec motions == %d\n", c, nr_begin_control); fprintf (spec_info->dump, ";; Procedure %cr-be-in-control-spec motions == %d\n", c, nr_be_in_control); } #ifdef ENABLE_CHECKING /* After reload ia64 backend clobbers CFG, so can't check anything. */ if (!reload_completed) check_cfg (0, 0); #endif current_sched_info = NULL; } /* Fix INSN_TICKs of the instructions in the current block as well as INSN_TICKs of their dependents. HEAD and TAIL are the begin and the end of the current scheduled block. */ static void fix_inter_tick (rtx head, rtx tail) { /* Set of instructions with corrected INSN_TICK. */ bitmap_head processed; /* ??? It is doubtful if we should assume that cycle advance happens on basic block boundaries. Basically insns that are unconditionally ready on the start of the block are more preferable then those which have a one cycle dependency over insn from the previous block. */ int next_clock = clock_var + 1; bitmap_initialize (&processed, 0); /* Iterates over scheduled instructions and fix their INSN_TICKs and INSN_TICKs of dependent instructions, so that INSN_TICKs are consistent across different blocks. */ for (tail = NEXT_INSN (tail); head != tail; head = NEXT_INSN (head)) { if (INSN_P (head)) { int tick; sd_iterator_def sd_it; dep_t dep; tick = INSN_TICK (head); gcc_assert (tick >= MIN_TICK); /* Fix INSN_TICK of instruction from just scheduled block. */ if (!bitmap_bit_p (&processed, INSN_LUID (head))) { bitmap_set_bit (&processed, INSN_LUID (head)); tick -= next_clock; if (tick < MIN_TICK) tick = MIN_TICK; INSN_TICK (head) = tick; } FOR_EACH_DEP (head, SD_LIST_RES_FORW, sd_it, dep) { rtx next; next = DEP_CON (dep); tick = INSN_TICK (next); if (tick != INVALID_TICK /* If NEXT has its INSN_TICK calculated, fix it. If not - it will be properly calculated from scratch later in fix_tick_ready. */ && !bitmap_bit_p (&processed, INSN_LUID (next))) { bitmap_set_bit (&processed, INSN_LUID (next)); tick -= next_clock; if (tick < MIN_TICK) tick = MIN_TICK; if (tick > INTER_TICK (next)) INTER_TICK (next) = tick; else tick = INTER_TICK (next); INSN_TICK (next) = tick; } } } } bitmap_clear (&processed); } /* Check if NEXT is ready to be added to the ready or queue list. If "yes", add it to the proper list. Returns: -1 - is not ready yet, 0 - added to the ready list, 0 < N - queued for N cycles. */ int try_ready (rtx next) { ds_t old_ts, *ts; ts = &TODO_SPEC (next); old_ts = *ts; gcc_assert (!(old_ts & ~(SPECULATIVE | HARD_DEP)) && ((old_ts & HARD_DEP) || (old_ts & SPECULATIVE))); if (sd_lists_empty_p (next, SD_LIST_BACK)) /* NEXT has all its dependencies resolved. */ { /* Remove HARD_DEP bit from NEXT's status. */ *ts &= ~HARD_DEP; if (current_sched_info->flags & DO_SPECULATION) /* Remove all speculative bits from NEXT's status. */ *ts &= ~SPECULATIVE; } else { /* One of the NEXT's dependencies has been resolved. Recalculate NEXT's status. */ *ts &= ~SPECULATIVE & ~HARD_DEP; if (sd_lists_empty_p (next, SD_LIST_HARD_BACK)) /* Now we've got NEXT with speculative deps only. 1. Look at the deps to see what we have to do. 2. Check if we can do 'todo'. */ { sd_iterator_def sd_it; dep_t dep; bool first_p = true; FOR_EACH_DEP (next, SD_LIST_BACK, sd_it, dep) { ds_t ds = DEP_STATUS (dep) & SPECULATIVE; if (first_p) { first_p = false; *ts = ds; } else *ts = ds_merge (*ts, ds); } if (dep_weak (*ts) < spec_info->weakness_cutoff) /* Too few points. */ *ts = (*ts & ~SPECULATIVE) | HARD_DEP; } else *ts |= HARD_DEP; } if (*ts & HARD_DEP) gcc_assert (*ts == old_ts && QUEUE_INDEX (next) == QUEUE_NOWHERE); else if (current_sched_info->new_ready) *ts = current_sched_info->new_ready (next, *ts); /* * if !(old_ts & SPECULATIVE) (e.g. HARD_DEP or 0), then insn might have its original pattern or changed (speculative) one. This is due to changing ebb in region scheduling. * But if (old_ts & SPECULATIVE), then we are pretty sure that insn has speculative pattern. We can't assert (!(*ts & HARD_DEP) || *ts == old_ts) here because control-speculative NEXT could have been discarded by sched-rgn.c (the same case as when discarded by can_schedule_ready_p ()). */ if ((*ts & SPECULATIVE) /* If (old_ts == *ts), then (old_ts & SPECULATIVE) and we don't need to change anything. */ && *ts != old_ts) { int res; rtx new_pat; gcc_assert ((*ts & SPECULATIVE) && !(*ts & ~SPECULATIVE)); res = speculate_insn (next, *ts, &new_pat); switch (res) { case -1: /* It would be nice to change DEP_STATUS of all dependences, which have ((DEP_STATUS & SPECULATIVE) == *ts) to HARD_DEP, so we won't reanalyze anything. */ *ts = (*ts & ~SPECULATIVE) | HARD_DEP; break; case 0: /* We follow the rule, that every speculative insn has non-null ORIG_PAT. */ if (!ORIG_PAT (next)) ORIG_PAT (next) = PATTERN (next); break; case 1: if (!ORIG_PAT (next)) /* If we gonna to overwrite the original pattern of insn, save it. */ ORIG_PAT (next) = PATTERN (next); change_pattern (next, new_pat); break; default: gcc_unreachable (); } } /* We need to restore pattern only if (*ts == 0), because otherwise it is either correct (*ts & SPECULATIVE), or we simply don't care (*ts & HARD_DEP). */ gcc_assert (!ORIG_PAT (next) || !IS_SPECULATION_BRANCHY_CHECK_P (next)); if (*ts & HARD_DEP) { /* We can't assert (QUEUE_INDEX (next) == QUEUE_NOWHERE) here because control-speculative NEXT could have been discarded by sched-rgn.c (the same case as when discarded by can_schedule_ready_p ()). */ /*gcc_assert (QUEUE_INDEX (next) == QUEUE_NOWHERE);*/ change_queue_index (next, QUEUE_NOWHERE); return -1; } else if (!(*ts & BEGIN_SPEC) && ORIG_PAT (next) && !IS_SPECULATION_CHECK_P (next)) /* We should change pattern of every previously speculative instruction - and we determine if NEXT was speculative by using ORIG_PAT field. Except one case - speculation checks have ORIG_PAT pat too, so skip them. */ { change_pattern (next, ORIG_PAT (next)); ORIG_PAT (next) = 0; } if (sched_verbose >= 2) { int s = TODO_SPEC (next); fprintf (sched_dump, ";;\t\tdependencies resolved: insn %s", (*current_sched_info->print_insn) (next, 0)); if (spec_info && spec_info->dump) { if (s & BEGIN_DATA) fprintf (spec_info->dump, "; data-spec;"); if (s & BEGIN_CONTROL) fprintf (spec_info->dump, "; control-spec;"); if (s & BE_IN_CONTROL) fprintf (spec_info->dump, "; in-control-spec;"); } fprintf (sched_dump, "\n"); } adjust_priority (next); return fix_tick_ready (next); } /* Calculate INSN_TICK of NEXT and add it to either ready or queue list. */ static int fix_tick_ready (rtx next) { int tick, delay; if (!sd_lists_empty_p (next, SD_LIST_RES_BACK)) { int full_p; sd_iterator_def sd_it; dep_t dep; tick = INSN_TICK (next); /* if tick is not equal to INVALID_TICK, then update INSN_TICK of NEXT with the most recent resolved dependence cost. Otherwise, recalculate from scratch. */ full_p = (tick == INVALID_TICK); FOR_EACH_DEP (next, SD_LIST_RES_BACK, sd_it, dep) { rtx pro = DEP_PRO (dep); int tick1; gcc_assert (INSN_TICK (pro) >= MIN_TICK); tick1 = INSN_TICK (pro) + dep_cost (dep); if (tick1 > tick) tick = tick1; if (!full_p) break; } } else tick = -1; INSN_TICK (next) = tick; delay = tick - clock_var; if (delay <= 0) delay = QUEUE_READY; change_queue_index (next, delay); return delay; } /* Move NEXT to the proper queue list with (DELAY >= 1), or add it to the ready list (DELAY == QUEUE_READY), or remove it from ready and queue lists at all (DELAY == QUEUE_NOWHERE). */ static void change_queue_index (rtx next, int delay) { int i = QUEUE_INDEX (next); gcc_assert (QUEUE_NOWHERE <= delay && delay <= max_insn_queue_index && delay != 0); gcc_assert (i != QUEUE_SCHEDULED); if ((delay > 0 && NEXT_Q_AFTER (q_ptr, delay) == i) || (delay < 0 && delay == i)) /* We have nothing to do. */ return; /* Remove NEXT from wherever it is now. */ if (i == QUEUE_READY) ready_remove_insn (next); else if (i >= 0) queue_remove (next); /* Add it to the proper place. */ if (delay == QUEUE_READY) ready_add (readyp, next, false); else if (delay >= 1) queue_insn (next, delay); if (sched_verbose >= 2) { fprintf (sched_dump, ";;\t\ttick updated: insn %s", (*current_sched_info->print_insn) (next, 0)); if (delay == QUEUE_READY) fprintf (sched_dump, " into ready\n"); else if (delay >= 1) fprintf (sched_dump, " into queue with cost=%d\n", delay); else fprintf (sched_dump, " removed from ready or queue lists\n"); } } /* Extend H_I_D data. */ static void extend_h_i_d (void) { /* We use LUID 0 for the fake insn (UID 0) which holds dependencies for pseudos which do not cross calls. */ int new_max_uid = get_max_uid () + 1; h_i_d = xrecalloc (h_i_d, new_max_uid, old_max_uid, sizeof (*h_i_d)); old_max_uid = new_max_uid; if (targetm.sched.h_i_d_extended) targetm.sched.h_i_d_extended (); } /* Extend READY, READY_TRY and CHOICE_STACK arrays. N_NEW_INSNS is the number of additional elements to allocate. */ static void extend_ready (int n_new_insns) { int i; readyp->veclen = rgn_n_insns + n_new_insns + 1 + issue_rate; readyp->vec = XRESIZEVEC (rtx, readyp->vec, readyp->veclen); ready_try = xrecalloc (ready_try, rgn_n_insns + n_new_insns + 1, rgn_n_insns + 1, sizeof (char)); rgn_n_insns += n_new_insns; choice_stack = XRESIZEVEC (struct choice_entry, choice_stack, rgn_n_insns + 1); for (i = rgn_n_insns; n_new_insns--; i--) choice_stack[i].state = xmalloc (dfa_state_size); } /* Extend global scheduler structures (those, that live across calls to schedule_block) to include information about just emitted INSN. */ static void extend_global (rtx insn) { gcc_assert (INSN_P (insn)); /* These structures have scheduler scope. */ /* Init h_i_d. */ extend_h_i_d (); init_h_i_d (insn); /* Init data handled in sched-deps.c. */ sd_init_insn (insn); /* Extend dependency caches by one element. */ extend_dependency_caches (1, false); } /* Extends global and local scheduler structures to include information about just emitted INSN. */ static void extend_all (rtx insn) { extend_global (insn); /* These structures have block scope. */ extend_ready (1); (*current_sched_info->add_remove_insn) (insn, 0); } /* Initialize h_i_d entry of the new INSN with default values. Values, that are not explicitly initialized here, hold zero. */ static void init_h_i_d (rtx insn) { INSN_LUID (insn) = luid++; INSN_COST (insn) = -1; TODO_SPEC (insn) = HARD_DEP; QUEUE_INDEX (insn) = QUEUE_NOWHERE; INSN_TICK (insn) = INVALID_TICK; INTER_TICK (insn) = INVALID_TICK; find_insn_reg_weight1 (insn); } /* Generates recovery code for INSN. */ static void generate_recovery_code (rtx insn) { if (TODO_SPEC (insn) & BEGIN_SPEC) begin_speculative_block (insn); /* Here we have insn with no dependencies to instructions other then CHECK_SPEC ones. */ if (TODO_SPEC (insn) & BE_IN_SPEC) add_to_speculative_block (insn); } /* Helper function. Tries to add speculative dependencies of type FS between instructions in deps_list L and TWIN. */ static void process_insn_forw_deps_be_in_spec (rtx insn, rtx twin, ds_t fs) { sd_iterator_def sd_it; dep_t dep; FOR_EACH_DEP (insn, SD_LIST_FORW, sd_it, dep) { ds_t ds; rtx consumer; consumer = DEP_CON (dep); ds = DEP_STATUS (dep); if (/* If we want to create speculative dep. */ fs /* And we can do that because this is a true dep. */ && (ds & DEP_TYPES) == DEP_TRUE) { gcc_assert (!(ds & BE_IN_SPEC)); if (/* If this dep can be overcome with 'begin speculation'. */ ds & BEGIN_SPEC) /* Then we have a choice: keep the dep 'begin speculative' or transform it into 'be in speculative'. */ { if (/* In try_ready we assert that if insn once became ready it can be removed from the ready (or queue) list only due to backend decision. Hence we can't let the probability of the speculative dep to decrease. */ dep_weak (ds) <= dep_weak (fs)) { ds_t new_ds; new_ds = (ds & ~BEGIN_SPEC) | fs; if (/* consumer can 'be in speculative'. */ sched_insn_is_legitimate_for_speculation_p (consumer, new_ds)) /* Transform it to be in speculative. */ ds = new_ds; } } else /* Mark the dep as 'be in speculative'. */ ds |= fs; } { dep_def _new_dep, *new_dep = &_new_dep; init_dep_1 (new_dep, twin, consumer, DEP_TYPE (dep), ds); sd_add_dep (new_dep, false); } } } /* Generates recovery code for BEGIN speculative INSN. */ static void begin_speculative_block (rtx insn) { if (TODO_SPEC (insn) & BEGIN_DATA) nr_begin_data++; if (TODO_SPEC (insn) & BEGIN_CONTROL) nr_begin_control++; create_check_block_twin (insn, false); TODO_SPEC (insn) &= ~BEGIN_SPEC; } /* Generates recovery code for BE_IN speculative INSN. */ static void add_to_speculative_block (rtx insn) { ds_t ts; sd_iterator_def sd_it; dep_t dep; rtx twins = NULL; rtx_vec_t priorities_roots; ts = TODO_SPEC (insn); gcc_assert (!(ts & ~BE_IN_SPEC)); if (ts & BE_IN_DATA) nr_be_in_data++; if (ts & BE_IN_CONTROL) nr_be_in_control++; TODO_SPEC (insn) &= ~BE_IN_SPEC; gcc_assert (!TODO_SPEC (insn)); DONE_SPEC (insn) |= ts; /* First we convert all simple checks to branchy. */ for (sd_it = sd_iterator_start (insn, SD_LIST_SPEC_BACK); sd_iterator_cond (&sd_it, &dep);) { rtx check = DEP_PRO (dep); if (IS_SPECULATION_SIMPLE_CHECK_P (check)) { create_check_block_twin (check, true); /* Restart search. */ sd_it = sd_iterator_start (insn, SD_LIST_SPEC_BACK); } else /* Continue search. */ sd_iterator_next (&sd_it); } priorities_roots = NULL; clear_priorities (insn, &priorities_roots); while (1) { rtx check, twin; basic_block rec; /* Get the first backward dependency of INSN. */ sd_it = sd_iterator_start (insn, SD_LIST_SPEC_BACK); if (!sd_iterator_cond (&sd_it, &dep)) /* INSN has no backward dependencies left. */ break; gcc_assert ((DEP_STATUS (dep) & BEGIN_SPEC) == 0 && (DEP_STATUS (dep) & BE_IN_SPEC) != 0 && (DEP_STATUS (dep) & DEP_TYPES) == DEP_TRUE); check = DEP_PRO (dep); gcc_assert (!IS_SPECULATION_CHECK_P (check) && !ORIG_PAT (check) && QUEUE_INDEX (check) == QUEUE_NOWHERE); rec = BLOCK_FOR_INSN (check); twin = emit_insn_before (copy_insn (PATTERN (insn)), BB_END (rec)); extend_global (twin); sd_copy_back_deps (twin, insn, true); if (sched_verbose && spec_info->dump) /* INSN_BB (insn) isn't determined for twin insns yet. So we can't use current_sched_info->print_insn. */ fprintf (spec_info->dump, ";;\t\tGenerated twin insn : %d/rec%d\n", INSN_UID (twin), rec->index); twins = alloc_INSN_LIST (twin, twins); /* Add dependences between TWIN and all appropriate instructions from REC. */ FOR_EACH_DEP (insn, SD_LIST_SPEC_BACK, sd_it, dep) { rtx pro = DEP_PRO (dep); gcc_assert (DEP_TYPE (dep) == REG_DEP_TRUE); /* INSN might have dependencies from the instructions from several recovery blocks. At this iteration we process those producers that reside in REC. */ if (BLOCK_FOR_INSN (pro) == rec) { dep_def _new_dep, *new_dep = &_new_dep; init_dep (new_dep, pro, twin, REG_DEP_TRUE); sd_add_dep (new_dep, false); } } process_insn_forw_deps_be_in_spec (insn, twin, ts); /* Remove all dependencies between INSN and insns in REC. */ for (sd_it = sd_iterator_start (insn, SD_LIST_SPEC_BACK); sd_iterator_cond (&sd_it, &dep);) { rtx pro = DEP_PRO (dep); if (BLOCK_FOR_INSN (pro) == rec) sd_delete_dep (sd_it); else sd_iterator_next (&sd_it); } } /* We couldn't have added the dependencies between INSN and TWINS earlier because that would make TWINS appear in the INSN_BACK_DEPS (INSN). */ while (twins) { rtx twin; twin = XEXP (twins, 0); { dep_def _new_dep, *new_dep = &_new_dep; init_dep (new_dep, insn, twin, REG_DEP_OUTPUT); sd_add_dep (new_dep, false); } twin = XEXP (twins, 1); free_INSN_LIST_node (twins); twins = twin; } calc_priorities (priorities_roots); VEC_free (rtx, heap, priorities_roots); } /* Extends and fills with zeros (only the new part) array pointed to by P. */ void * xrecalloc (void *p, size_t new_nmemb, size_t old_nmemb, size_t size) { gcc_assert (new_nmemb >= old_nmemb); p = XRESIZEVAR (void, p, new_nmemb * size); memset (((char *) p) + old_nmemb * size, 0, (new_nmemb - old_nmemb) * size); return p; } /* Return the probability of speculation success for the speculation status DS. */ static dw_t dep_weak (ds_t ds) { ds_t res = 1, dt; int n = 0; dt = FIRST_SPEC_TYPE; do { if (ds & dt) { res *= (ds_t) get_dep_weak (ds, dt); n++; } if (dt == LAST_SPEC_TYPE) break; dt <<= SPEC_TYPE_SHIFT; } while (1); gcc_assert (n); while (--n) res /= MAX_DEP_WEAK; if (res < MIN_DEP_WEAK) res = MIN_DEP_WEAK; gcc_assert (res <= MAX_DEP_WEAK); return (dw_t) res; } /* Helper function. Find fallthru edge from PRED. */ static edge find_fallthru_edge (basic_block pred) { edge e; edge_iterator ei; basic_block succ; succ = pred->next_bb; gcc_assert (succ->prev_bb == pred); if (EDGE_COUNT (pred->succs) <= EDGE_COUNT (succ->preds)) { FOR_EACH_EDGE (e, ei, pred->succs) if (e->flags & EDGE_FALLTHRU) { gcc_assert (e->dest == succ); return e; } } else { FOR_EACH_EDGE (e, ei, succ->preds) if (e->flags & EDGE_FALLTHRU) { gcc_assert (e->src == pred); return e; } } return NULL; } /* Initialize BEFORE_RECOVERY variable. */ static void init_before_recovery (void) { basic_block last; edge e; last = EXIT_BLOCK_PTR->prev_bb; e = find_fallthru_edge (last); if (e) { /* We create two basic blocks: 1. Single instruction block is inserted right after E->SRC and has jump to 2. Empty block right before EXIT_BLOCK. Between these two blocks recovery blocks will be emitted. */ basic_block single, empty; rtx x, label; single = create_empty_bb (last); empty = create_empty_bb (single); single->count = last->count; empty->count = last->count; single->frequency = last->frequency; empty->frequency = last->frequency; BB_COPY_PARTITION (single, last); BB_COPY_PARTITION (empty, last); redirect_edge_succ (e, single); make_single_succ_edge (single, empty, 0); make_single_succ_edge (empty, EXIT_BLOCK_PTR, EDGE_FALLTHRU | EDGE_CAN_FALLTHRU); label = block_label (empty); x = emit_jump_insn_after (gen_jump (label), BB_END (single)); JUMP_LABEL (x) = label; LABEL_NUSES (label)++; extend_global (x); emit_barrier_after (x); add_block (empty, 0); add_block (single, 0); before_recovery = single; if (sched_verbose >= 2 && spec_info->dump) fprintf (spec_info->dump, ";;\t\tFixed fallthru to EXIT : %d->>%d->%d->>EXIT\n", last->index, single->index, empty->index); } else before_recovery = last; } /* Returns new recovery block. */ static basic_block create_recovery_block (void) { rtx label; rtx barrier; basic_block rec; haifa_recovery_bb_recently_added_p = true; haifa_recovery_bb_ever_added_p = true; if (!before_recovery) init_before_recovery (); barrier = get_last_bb_insn (before_recovery); gcc_assert (BARRIER_P (barrier)); label = emit_label_after (gen_label_rtx (), barrier); rec = create_basic_block (label, label, before_recovery); /* Recovery block always end with an unconditional jump. */ emit_barrier_after (BB_END (rec)); if (BB_PARTITION (before_recovery) != BB_UNPARTITIONED) BB_SET_PARTITION (rec, BB_COLD_PARTITION); if (sched_verbose && spec_info->dump) fprintf (spec_info->dump, ";;\t\tGenerated recovery block rec%d\n", rec->index); before_recovery = rec; return rec; } /* This function creates recovery code for INSN. If MUTATE_P is nonzero, INSN is a simple check, that should be converted to branchy one. */ static void create_check_block_twin (rtx insn, bool mutate_p) { basic_block rec; rtx label, check, twin; ds_t fs; sd_iterator_def sd_it; dep_t dep; dep_def _new_dep, *new_dep = &_new_dep; gcc_assert (ORIG_PAT (insn) && (!mutate_p || (IS_SPECULATION_SIMPLE_CHECK_P (insn) && !(TODO_SPEC (insn) & SPECULATIVE)))); /* Create recovery block. */ if (mutate_p || targetm.sched.needs_block_p (insn)) { rec = create_recovery_block (); label = BB_HEAD (rec); } else { rec = EXIT_BLOCK_PTR; label = 0; } /* Emit CHECK. */ check = targetm.sched.gen_check (insn, label, mutate_p); if (rec != EXIT_BLOCK_PTR) { /* To have mem_reg alive at the beginning of second_bb, we emit check BEFORE insn, so insn after splitting insn will be at the beginning of second_bb, which will provide us with the correct life information. */ check = emit_jump_insn_before (check, insn); JUMP_LABEL (check) = label; LABEL_NUSES (label)++; } else check = emit_insn_before (check, insn); /* Extend data structures. */ extend_all (check); RECOVERY_BLOCK (check) = rec; if (sched_verbose && spec_info->dump) fprintf (spec_info->dump, ";;\t\tGenerated check insn : %s\n", (*current_sched_info->print_insn) (check, 0)); gcc_assert (ORIG_PAT (insn)); /* Initialize TWIN (twin is a duplicate of original instruction in the recovery block). */ if (rec != EXIT_BLOCK_PTR) { sd_iterator_def sd_it; dep_t dep; FOR_EACH_DEP (insn, SD_LIST_RES_BACK, sd_it, dep) if ((DEP_STATUS (dep) & DEP_OUTPUT) != 0) { struct _dep _dep2, *dep2 = &_dep2; init_dep (dep2, DEP_PRO (dep), check, REG_DEP_TRUE); sd_add_dep (dep2, true); } twin = emit_insn_after (ORIG_PAT (insn), BB_END (rec)); extend_global (twin); if (sched_verbose && spec_info->dump) /* INSN_BB (insn) isn't determined for twin insns yet. So we can't use current_sched_info->print_insn. */ fprintf (spec_info->dump, ";;\t\tGenerated twin insn : %d/rec%d\n", INSN_UID (twin), rec->index); } else { ORIG_PAT (check) = ORIG_PAT (insn); HAS_INTERNAL_DEP (check) = 1; twin = check; /* ??? We probably should change all OUTPUT dependencies to (TRUE | OUTPUT). */ } /* Copy all resolved back dependencies of INSN to TWIN. This will provide correct value for INSN_TICK (TWIN). */ sd_copy_back_deps (twin, insn, true); if (rec != EXIT_BLOCK_PTR) /* In case of branchy check, fix CFG. */ { basic_block first_bb, second_bb; rtx jump; edge e; int edge_flags; first_bb = BLOCK_FOR_INSN (check); e = split_block (first_bb, check); /* split_block emits note if *check == BB_END. Probably it is better to rip that note off. */ gcc_assert (e->src == first_bb); second_bb = e->dest; /* This is fixing of incoming edge. */ /* ??? Which other flags should be specified? */ if (BB_PARTITION (first_bb) != BB_PARTITION (rec)) /* Partition type is the same, if it is "unpartitioned". */ edge_flags = EDGE_CROSSING; else edge_flags = 0; e = make_edge (first_bb, rec, edge_flags); add_block (second_bb, first_bb); gcc_assert (NOTE_INSN_BASIC_BLOCK_P (BB_HEAD (second_bb))); label = block_label (second_bb); jump = emit_jump_insn_after (gen_jump (label), BB_END (rec)); JUMP_LABEL (jump) = label; LABEL_NUSES (label)++; extend_global (jump); if (BB_PARTITION (second_bb) != BB_PARTITION (rec)) /* Partition type is the same, if it is "unpartitioned". */ { /* Rewritten from cfgrtl.c. */ if (flag_reorder_blocks_and_partition && targetm.have_named_sections /*&& !any_condjump_p (jump)*/) /* any_condjump_p (jump) == false. We don't need the same note for the check because any_condjump_p (check) == true. */ { REG_NOTES (jump) = gen_rtx_EXPR_LIST (REG_CROSSING_JUMP, NULL_RTX, REG_NOTES (jump)); } edge_flags = EDGE_CROSSING; } else edge_flags = 0; make_single_succ_edge (rec, second_bb, edge_flags); add_block (rec, EXIT_BLOCK_PTR); } /* Move backward dependences from INSN to CHECK and move forward dependences from INSN to TWIN. */ /* First, create dependencies between INSN's producers and CHECK & TWIN. */ FOR_EACH_DEP (insn, SD_LIST_BACK, sd_it, dep) { rtx pro = DEP_PRO (dep); ds_t ds; /* If BEGIN_DATA: [insn ~~TRUE~~> producer]: check --TRUE--> producer ??? or ANTI ??? twin --TRUE--> producer twin --ANTI--> check If BEGIN_CONTROL: [insn ~~ANTI~~> producer]: check --ANTI--> producer twin --ANTI--> producer twin --ANTI--> check If BE_IN_SPEC: [insn ~~TRUE~~> producer]: check ~~TRUE~~> producer twin ~~TRUE~~> producer twin --ANTI--> check */ ds = DEP_STATUS (dep); if (ds & BEGIN_SPEC) { gcc_assert (!mutate_p); ds &= ~BEGIN_SPEC; } init_dep_1 (new_dep, pro, check, DEP_TYPE (dep), ds); sd_add_dep (new_dep, false); if (rec != EXIT_BLOCK_PTR) { DEP_CON (new_dep) = twin; sd_add_dep (new_dep, false); } } /* Second, remove backward dependencies of INSN. */ for (sd_it = sd_iterator_start (insn, SD_LIST_SPEC_BACK); sd_iterator_cond (&sd_it, &dep);) { if ((DEP_STATUS (dep) & BEGIN_SPEC) || mutate_p) /* We can delete this dep because we overcome it with BEGIN_SPECULATION. */ sd_delete_dep (sd_it); else sd_iterator_next (&sd_it); } /* Future Speculations. Determine what BE_IN speculations will be like. */ fs = 0; /* Fields (DONE_SPEC (x) & BEGIN_SPEC) and CHECK_SPEC (x) are set only here. */ gcc_assert (!DONE_SPEC (insn)); if (!mutate_p) { ds_t ts = TODO_SPEC (insn); DONE_SPEC (insn) = ts & BEGIN_SPEC; CHECK_SPEC (check) = ts & BEGIN_SPEC; /* Luckiness of future speculations solely depends upon initial BEGIN speculation. */ if (ts & BEGIN_DATA) fs = set_dep_weak (fs, BE_IN_DATA, get_dep_weak (ts, BEGIN_DATA)); if (ts & BEGIN_CONTROL) fs = set_dep_weak (fs, BE_IN_CONTROL, get_dep_weak (ts, BEGIN_CONTROL)); } else CHECK_SPEC (check) = CHECK_SPEC (insn); /* Future speculations: call the helper. */ process_insn_forw_deps_be_in_spec (insn, twin, fs); if (rec != EXIT_BLOCK_PTR) { /* Which types of dependencies should we use here is, generally, machine-dependent question... But, for now, it is not. */ if (!mutate_p) { init_dep (new_dep, insn, check, REG_DEP_TRUE); sd_add_dep (new_dep, false); init_dep (new_dep, insn, twin, REG_DEP_OUTPUT); sd_add_dep (new_dep, false); } else { if (spec_info->dump) fprintf (spec_info->dump, ";;\t\tRemoved simple check : %s\n", (*current_sched_info->print_insn) (insn, 0)); /* Remove all dependencies of the INSN. */ { sd_it = sd_iterator_start (insn, (SD_LIST_FORW | SD_LIST_BACK | SD_LIST_RES_BACK)); while (sd_iterator_cond (&sd_it, &dep)) sd_delete_dep (sd_it); } /* If former check (INSN) already was moved to the ready (or queue) list, add new check (CHECK) there too. */ if (QUEUE_INDEX (insn) != QUEUE_NOWHERE) try_ready (check); /* Remove old check from instruction stream and free its data. */ sched_remove_insn (insn); } init_dep (new_dep, check, twin, REG_DEP_ANTI); sd_add_dep (new_dep, false); } else { init_dep_1 (new_dep, insn, check, REG_DEP_TRUE, DEP_TRUE | DEP_OUTPUT); sd_add_dep (new_dep, false); } if (!mutate_p) /* Fix priorities. If MUTATE_P is nonzero, this is not necessary, because it'll be done later in add_to_speculative_block. */ { rtx_vec_t priorities_roots = NULL; clear_priorities (twin, &priorities_roots); calc_priorities (priorities_roots); VEC_free (rtx, heap, priorities_roots); } } /* Removes dependency between instructions in the recovery block REC and usual region instructions. It keeps inner dependences so it won't be necessary to recompute them. */ static void fix_recovery_deps (basic_block rec) { rtx note, insn, jump, ready_list = 0; bitmap_head in_ready; rtx link; bitmap_initialize (&in_ready, 0); /* NOTE - a basic block note. */ note = NEXT_INSN (BB_HEAD (rec)); gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); insn = BB_END (rec); gcc_assert (JUMP_P (insn)); insn = PREV_INSN (insn); do { sd_iterator_def sd_it; dep_t dep; for (sd_it = sd_iterator_start (insn, SD_LIST_FORW); sd_iterator_cond (&sd_it, &dep);) { rtx consumer = DEP_CON (dep); if (BLOCK_FOR_INSN (consumer) != rec) { sd_delete_dep (sd_it); if (!bitmap_bit_p (&in_ready, INSN_LUID (consumer))) { ready_list = alloc_INSN_LIST (consumer, ready_list); bitmap_set_bit (&in_ready, INSN_LUID (consumer)); } } else { gcc_assert ((DEP_STATUS (dep) & DEP_TYPES) == DEP_TRUE); sd_iterator_next (&sd_it); } } insn = PREV_INSN (insn); } while (insn != note); bitmap_clear (&in_ready); /* Try to add instructions to the ready or queue list. */ for (link = ready_list; link; link = XEXP (link, 1)) try_ready (XEXP (link, 0)); free_INSN_LIST_list (&ready_list); /* Fixing jump's dependences. */ insn = BB_HEAD (rec); jump = BB_END (rec); gcc_assert (LABEL_P (insn)); insn = NEXT_INSN (insn); gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); add_jump_dependencies (insn, jump); } /* Changes pattern of the INSN to NEW_PAT. */ static void change_pattern (rtx insn, rtx new_pat) { int t; t = validate_change (insn, &PATTERN (insn), new_pat, 0); gcc_assert (t); /* Invalidate INSN_COST, so it'll be recalculated. */ INSN_COST (insn) = -1; /* Invalidate INSN_TICK, so it'll be recalculated. */ INSN_TICK (insn) = INVALID_TICK; dfa_clear_single_insn_cache (insn); } /* Return true if INSN can potentially be speculated with type DS. */ bool sched_insn_is_legitimate_for_speculation_p (const_rtx insn, ds_t ds) { if (HAS_INTERNAL_DEP (insn)) return false; if (!NONJUMP_INSN_P (insn)) return false; if (SCHED_GROUP_P (insn)) return false; if (IS_SPECULATION_CHECK_P (insn)) return false; if (side_effects_p (PATTERN (insn))) return false; if ((ds & BE_IN_SPEC) && may_trap_p (PATTERN (insn))) return false; return true; } /* -1 - can't speculate, 0 - for speculation with REQUEST mode it is OK to use current instruction pattern, 1 - need to change pattern for *NEW_PAT to be speculative. */ static int speculate_insn (rtx insn, ds_t request, rtx *new_pat) { gcc_assert (current_sched_info->flags & DO_SPECULATION && (request & SPECULATIVE) && sched_insn_is_legitimate_for_speculation_p (insn, request)); if ((request & spec_info->mask) != request) return -1; if (request & BE_IN_SPEC && !(request & BEGIN_SPEC)) return 0; return targetm.sched.speculate_insn (insn, request & BEGIN_SPEC, new_pat); } /* Print some information about block BB, which starts with HEAD and ends with TAIL, before scheduling it. I is zero, if scheduler is about to start with the fresh ebb. */ static void dump_new_block_header (int i, basic_block bb, rtx head, rtx tail) { if (!i) fprintf (sched_dump, ";; ======================================================\n"); else fprintf (sched_dump, ";; =====================ADVANCING TO=====================\n"); fprintf (sched_dump, ";; -- basic block %d from %d to %d -- %s reload\n", bb->index, INSN_UID (head), INSN_UID (tail), (reload_completed ? "after" : "before")); fprintf (sched_dump, ";; ======================================================\n"); fprintf (sched_dump, "\n"); } /* Unlink basic block notes and labels and saves them, so they can be easily restored. We unlink basic block notes in EBB to provide back-compatibility with the previous code, as target backends assume, that there'll be only instructions between current_sched_info->{head and tail}. We restore these notes as soon as we can. FIRST (LAST) is the first (last) basic block in the ebb. NB: In usual case (FIRST == LAST) nothing is really done. */ void unlink_bb_notes (basic_block first, basic_block last) { /* We DON'T unlink basic block notes of the first block in the ebb. */ if (first == last) return; bb_header = xmalloc (last_basic_block * sizeof (*bb_header)); /* Make a sentinel. */ if (last->next_bb != EXIT_BLOCK_PTR) bb_header[last->next_bb->index] = 0; first = first->next_bb; do { rtx prev, label, note, next; label = BB_HEAD (last); if (LABEL_P (label)) note = NEXT_INSN (label); else note = label; gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); prev = PREV_INSN (label); next = NEXT_INSN (note); gcc_assert (prev && next); NEXT_INSN (prev) = next; PREV_INSN (next) = prev; bb_header[last->index] = label; if (last == first) break; last = last->prev_bb; } while (1); } /* Restore basic block notes. FIRST is the first basic block in the ebb. */ static void restore_bb_notes (basic_block first) { if (!bb_header) return; /* We DON'T unlink basic block notes of the first block in the ebb. */ first = first->next_bb; /* Remember: FIRST is actually a second basic block in the ebb. */ while (first != EXIT_BLOCK_PTR && bb_header[first->index]) { rtx prev, label, note, next; label = bb_header[first->index]; prev = PREV_INSN (label); next = NEXT_INSN (prev); if (LABEL_P (label)) note = NEXT_INSN (label); else note = label; gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); bb_header[first->index] = 0; NEXT_INSN (prev) = label; NEXT_INSN (note) = next; PREV_INSN (next) = note; first = first->next_bb; } free (bb_header); bb_header = 0; } /* Extend per basic block data structures of the scheduler. If BB is NULL, initialize structures for the whole CFG. Otherwise, initialize them for the just created BB. */ static void extend_bb (void) { rtx insn; old_last_basic_block = last_basic_block; /* The following is done to keep current_sched_info->next_tail non null. */ insn = BB_END (EXIT_BLOCK_PTR->prev_bb); if (NEXT_INSN (insn) == 0 || (!NOTE_P (insn) && !LABEL_P (insn) /* Don't emit a NOTE if it would end up before a BARRIER. */ && !BARRIER_P (NEXT_INSN (insn)))) { rtx note = emit_note_after (NOTE_INSN_DELETED, insn); /* Make insn appear outside BB. */ set_block_for_insn (note, NULL); BB_END (EXIT_BLOCK_PTR->prev_bb) = insn; } } /* Add a basic block BB to extended basic block EBB. If EBB is EXIT_BLOCK_PTR, then BB is recovery block. If EBB is NULL, then BB should be a new region. */ void add_block (basic_block bb, basic_block ebb) { gcc_assert (current_sched_info->flags & NEW_BBS); extend_bb (); if (current_sched_info->add_block) /* This changes only data structures of the front-end. */ current_sched_info->add_block (bb, ebb); } /* Helper function. Fix CFG after both in- and inter-block movement of control_flow_insn_p JUMP. */ static void fix_jump_move (rtx jump) { basic_block bb, jump_bb, jump_bb_next; bb = BLOCK_FOR_INSN (PREV_INSN (jump)); jump_bb = BLOCK_FOR_INSN (jump); jump_bb_next = jump_bb->next_bb; gcc_assert (current_sched_info->flags & SCHED_EBB || IS_SPECULATION_BRANCHY_CHECK_P (jump)); if (!NOTE_INSN_BASIC_BLOCK_P (BB_END (jump_bb_next))) /* if jump_bb_next is not empty. */ BB_END (jump_bb) = BB_END (jump_bb_next); if (BB_END (bb) != PREV_INSN (jump)) /* Then there are instruction after jump that should be placed to jump_bb_next. */ BB_END (jump_bb_next) = BB_END (bb); else /* Otherwise jump_bb_next is empty. */ BB_END (jump_bb_next) = NEXT_INSN (BB_HEAD (jump_bb_next)); /* To make assertion in move_insn happy. */ BB_END (bb) = PREV_INSN (jump); update_bb_for_insn (jump_bb_next); } /* Fix CFG after interblock movement of control_flow_insn_p JUMP. */ static void move_block_after_check (rtx jump) { basic_block bb, jump_bb, jump_bb_next; VEC(edge,gc) *t; bb = BLOCK_FOR_INSN (PREV_INSN (jump)); jump_bb = BLOCK_FOR_INSN (jump); jump_bb_next = jump_bb->next_bb; update_bb_for_insn (jump_bb); gcc_assert (IS_SPECULATION_CHECK_P (jump) || IS_SPECULATION_CHECK_P (BB_END (jump_bb_next))); unlink_block (jump_bb_next); link_block (jump_bb_next, bb); t = bb->succs; bb->succs = 0; move_succs (&(jump_bb->succs), bb); move_succs (&(jump_bb_next->succs), jump_bb); move_succs (&t, jump_bb_next); df_mark_solutions_dirty (); if (current_sched_info->fix_recovery_cfg) current_sched_info->fix_recovery_cfg (bb->index, jump_bb->index, jump_bb_next->index); } /* Helper function for move_block_after_check. This functions attaches edge vector pointed to by SUCCSP to block TO. */ static void move_succs (VEC(edge,gc) **succsp, basic_block to) { edge e; edge_iterator ei; gcc_assert (to->succs == 0); to->succs = *succsp; FOR_EACH_EDGE (e, ei, to->succs) e->src = to; *succsp = 0; } /* Remove INSN from the instruction stream. INSN should have any dependencies. */ static void sched_remove_insn (rtx insn) { sd_finish_insn (insn); change_queue_index (insn, QUEUE_NOWHERE); current_sched_info->add_remove_insn (insn, 1); remove_insn (insn); } /* Clear priorities of all instructions, that are forward dependent on INSN. Store in vector pointed to by ROOTS_PTR insns on which priority () should be invoked to initialize all cleared priorities. */ static void clear_priorities (rtx insn, rtx_vec_t *roots_ptr) { sd_iterator_def sd_it; dep_t dep; bool insn_is_root_p = true; gcc_assert (QUEUE_INDEX (insn) != QUEUE_SCHEDULED); FOR_EACH_DEP (insn, SD_LIST_BACK, sd_it, dep) { rtx pro = DEP_PRO (dep); if (INSN_PRIORITY_STATUS (pro) >= 0 && QUEUE_INDEX (insn) != QUEUE_SCHEDULED) { /* If DEP doesn't contribute to priority then INSN itself should be added to priority roots. */ if (contributes_to_priority_p (dep)) insn_is_root_p = false; INSN_PRIORITY_STATUS (pro) = -1; clear_priorities (pro, roots_ptr); } } if (insn_is_root_p) VEC_safe_push (rtx, heap, *roots_ptr, insn); } /* Recompute priorities of instructions, whose priorities might have been changed. ROOTS is a vector of instructions whose priority computation will trigger initialization of all cleared priorities. */ static void calc_priorities (rtx_vec_t roots) { int i; rtx insn; for (i = 0; VEC_iterate (rtx, roots, i, insn); i++) priority (insn); } /* Add dependences between JUMP and other instructions in the recovery block. INSN is the first insn the recovery block. */ static void add_jump_dependencies (rtx insn, rtx jump) { do { insn = NEXT_INSN (insn); if (insn == jump) break; if (sd_lists_empty_p (insn, SD_LIST_FORW)) { dep_def _new_dep, *new_dep = &_new_dep; init_dep (new_dep, insn, jump, REG_DEP_ANTI); sd_add_dep (new_dep, false); } } while (1); gcc_assert (!sd_lists_empty_p (jump, SD_LIST_BACK)); } /* Return the NOTE_INSN_BASIC_BLOCK of BB. */ rtx bb_note (basic_block bb) { rtx note; note = BB_HEAD (bb); if (LABEL_P (note)) note = NEXT_INSN (note); gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); return note; } #ifdef ENABLE_CHECKING /* Helper function for check_cfg. Return nonzero, if edge vector pointed to by EL has edge with TYPE in its flags. */ static int has_edge_p (VEC(edge,gc) *el, int type) { edge e; edge_iterator ei; FOR_EACH_EDGE (e, ei, el) if (e->flags & type) return 1; return 0; } /* Check few properties of CFG between HEAD and TAIL. If HEAD (TAIL) is NULL check from the beginning (till the end) of the instruction stream. */ static void check_cfg (rtx head, rtx tail) { rtx next_tail; basic_block bb = 0; int not_first = 0, not_last; if (head == NULL) head = get_insns (); if (tail == NULL) tail = get_last_insn (); next_tail = NEXT_INSN (tail); do { not_last = head != tail; if (not_first) gcc_assert (NEXT_INSN (PREV_INSN (head)) == head); if (not_last) gcc_assert (PREV_INSN (NEXT_INSN (head)) == head); if (LABEL_P (head) || (NOTE_INSN_BASIC_BLOCK_P (head) && (!not_first || (not_first && !LABEL_P (PREV_INSN (head)))))) { gcc_assert (bb == 0); bb = BLOCK_FOR_INSN (head); if (bb != 0) gcc_assert (BB_HEAD (bb) == head); else /* This is the case of jump table. See inside_basic_block_p (). */ gcc_assert (LABEL_P (head) && !inside_basic_block_p (head)); } if (bb == 0) { gcc_assert (!inside_basic_block_p (head)); head = NEXT_INSN (head); } else { gcc_assert (inside_basic_block_p (head) || NOTE_P (head)); gcc_assert (BLOCK_FOR_INSN (head) == bb); if (LABEL_P (head)) { head = NEXT_INSN (head); gcc_assert (NOTE_INSN_BASIC_BLOCK_P (head)); } else { if (control_flow_insn_p (head)) { gcc_assert (BB_END (bb) == head); if (any_uncondjump_p (head)) gcc_assert (EDGE_COUNT (bb->succs) == 1 && BARRIER_P (NEXT_INSN (head))); else if (any_condjump_p (head)) gcc_assert (/* Usual case. */ (EDGE_COUNT (bb->succs) > 1 && !BARRIER_P (NEXT_INSN (head))) /* Or jump to the next instruction. */ || (EDGE_COUNT (bb->succs) == 1 && (BB_HEAD (EDGE_I (bb->succs, 0)->dest) == JUMP_LABEL (head)))); } if (BB_END (bb) == head) { if (EDGE_COUNT (bb->succs) > 1) gcc_assert (control_flow_insn_p (head) || has_edge_p (bb->succs, EDGE_COMPLEX)); bb = 0; } head = NEXT_INSN (head); } } not_first = 1; } while (head != next_tail); gcc_assert (bb == 0); } #endif /* ENABLE_CHECKING */ #endif /* INSN_SCHEDULING */