const char *rs6000_sched_costly_dep_str;
enum rs6000_dependence_cost rs6000_sched_costly_dep;
+/* Support for -minsert-sched-nops option. */
+const char *rs6000_sched_insert_nops_str;
+enum rs6000_nop_insertion rs6000_sched_insert_nops;
+
/* Size of long double */
const char *rs6000_long_double_size_string;
int rs6000_long_double_type_size;
static int rs6000_variable_issue (FILE *, int, rtx, int);
static bool rs6000_rtx_costs (rtx, int, int, int *);
static int rs6000_adjust_cost (rtx, rtx, rtx, int);
+static bool is_microcoded_insn (rtx);
static int is_dispatch_slot_restricted (rtx);
+static bool is_cracked_insn (rtx);
+static bool is_branch_slot_insn (rtx);
static int rs6000_adjust_priority (rtx, int);
static int rs6000_issue_rate (void);
static bool rs6000_is_costly_dependence (rtx, rtx, rtx, int, int);
+static rtx get_next_active_insn (rtx, rtx);
+static bool insn_terminates_group_p (rtx , enum group_termination);
+static bool is_costly_group (rtx *, rtx);
+static int force_new_group (int, FILE *, rtx *, rtx, bool *, int, int *);
+static int redefine_groups (FILE *, int, rtx, rtx);
+static int pad_groups (FILE *, int, rtx, rtx);
+static void rs6000_sched_finish (FILE *, int);
static int rs6000_use_sched_lookahead (void);
static void rs6000_init_builtins (void);
#define TARGET_SCHED_ADJUST_PRIORITY rs6000_adjust_priority
#undef TARGET_SCHED_IS_COSTLY_DEPENDENCE
#define TARGET_SCHED_IS_COSTLY_DEPENDENCE rs6000_is_costly_dependence
+#undef TARGET_SCHED_FINISH
+#define TARGET_SCHED_FINISH rs6000_sched_finish
#undef TARGET_SCHED_FIRST_CYCLE_MULTIPASS_DFA_LOOKAHEAD
#define TARGET_SCHED_FIRST_CYCLE_MULTIPASS_DFA_LOOKAHEAD rs6000_use_sched_lookahead
rs6000_default_long_calls = (base[0] != 'n');
}
- /* Handle -mprioritize-restrcted-insns option. */
+ /* Handle -mprioritize-restricted-insns option. */
rs6000_sched_restricted_insns_priority = DEFAULT_RESTRICTED_INSNS_PRIORITY;
if (rs6000_sched_restricted_insns_priority_str)
rs6000_sched_restricted_insns_priority =
rs6000_sched_costly_dep = true_store_to_load_dep_costly;
else if (! strcmp (rs6000_sched_costly_dep_str, "store_to_load"))
rs6000_sched_costly_dep = store_to_load_dep_costly;
- else rs6000_sched_costly_dep = atoi (rs6000_sched_costly_dep_str);
+ else
+ rs6000_sched_costly_dep = atoi (rs6000_sched_costly_dep_str);
+ }
+
+ /* Handle -minsert-sched-nops option. */
+ rs6000_sched_insert_nops = DEFAULT_SCHED_FINISH_NOP_INSERTION_SCHEME;
+ if (rs6000_sched_insert_nops_str)
+ {
+ if (! strcmp (rs6000_sched_insert_nops_str, "no"))
+ rs6000_sched_insert_nops = sched_finish_none;
+ else if (! strcmp (rs6000_sched_insert_nops_str, "pad"))
+ rs6000_sched_insert_nops = sched_finish_pad_groups;
+ else if (! strcmp (rs6000_sched_insert_nops_str, "regroup_exact"))
+ rs6000_sched_insert_nops = sched_finish_regroup_exact;
+ else
+ rs6000_sched_insert_nops = atoi (rs6000_sched_insert_nops_str);
}
#ifdef TARGET_REGNAMES
if (rs6000_cpu == PROCESSOR_POWER4)
{
- enum attr_type type = get_attr_type (insn);
- if (type == TYPE_LOAD_EXT_U || type == TYPE_LOAD_EXT_UX
- || type == TYPE_LOAD_UX || type == TYPE_STORE_UX
- || type == TYPE_MFCR)
- return 0;
- else if (type == TYPE_LOAD_U || type == TYPE_STORE_U
- || type == TYPE_FPLOAD_U || type == TYPE_FPSTORE_U
- || type == TYPE_FPLOAD_UX || type == TYPE_FPSTORE_UX
- || type == TYPE_LOAD_EXT || type == TYPE_DELAYED_CR
- || type == TYPE_COMPARE || type == TYPE_DELAYED_COMPARE
- || type == TYPE_IMUL_COMPARE || type == TYPE_LMUL_COMPARE
- || type == TYPE_IDIV || type == TYPE_LDIV
- || type == TYPE_INSERT_WORD)
- return more > 2 ? more - 2 : 0;
+ if (is_microcoded_insn (insn))
+ return 0;
+ else if (is_cracked_insn (insn))
+ return more > 2 ? more - 2 : 0;
}
return more - 1;
return cost;
}
+/* The function returns a true if INSN is microcoded.
+ Return false ptherwise. */
+
+static bool
+is_microcoded_insn (rtx insn)
+{
+ if (!insn || !INSN_P (insn)
+ || GET_CODE (PATTERN (insn)) == USE
+ || GET_CODE (PATTERN (insn)) == CLOBBER)
+ return false;
+
+ if (rs6000_cpu == PROCESSOR_POWER4)
+ {
+ enum attr_type type = get_attr_type (insn);
+ if (type == TYPE_LOAD_EXT_U
+ || type == TYPE_LOAD_EXT_UX
+ || type == TYPE_LOAD_UX
+ || type == TYPE_STORE_UX
+ || type == TYPE_MFCR)
+ return true;
+ }
+
+ return false;
+}
+
/* The function returns a non-zero value if INSN can be scheduled only
- as the first insn in a dispatch group ("dispatch-slot restricted").
- In this case, the returned value indicates how many dispatch slots
- the insn occupies (at the beginning of the group).
+ as the first insn in a dispatch group ("dispatch-slot restricted").
+ In this case, the returned value indicates how many dispatch slots
+ the insn occupies (at the beginning of the group).
Return 0 otherwise. */
-static int
+static int
is_dispatch_slot_restricted (rtx insn)
{
enum attr_type type;
}
}
+/* The function returns true if INSN is cracked into 2 instructions
+ by the processor (and therefore occupies 2 issue slots). */
+
+static bool
+is_cracked_insn (rtx insn)
+{
+ if (!insn || !INSN_P (insn)
+ || GET_CODE (PATTERN (insn)) == USE
+ || GET_CODE (PATTERN (insn)) == CLOBBER)
+ return false;
+
+ if (rs6000_cpu == PROCESSOR_POWER4)
+ {
+ enum attr_type type = get_attr_type (insn);
+ if (type == TYPE_LOAD_U || type == TYPE_STORE_U
+ || type == TYPE_FPLOAD_U || type == TYPE_FPSTORE_U
+ || type == TYPE_FPLOAD_UX || type == TYPE_FPSTORE_UX
+ || type == TYPE_LOAD_EXT || type == TYPE_DELAYED_CR
+ || type == TYPE_COMPARE || type == TYPE_DELAYED_COMPARE
+ || type == TYPE_IMUL_COMPARE || type == TYPE_LMUL_COMPARE
+ || type == TYPE_IDIV || type == TYPE_LDIV
+ || type == TYPE_INSERT_WORD)
+ return true;
+ }
+
+ return false;
+}
+
+/* The function returns true if INSN can be issued only from
+ the branch slot. */
+
+static bool
+is_branch_slot_insn (rtx insn)
+{
+ if (!insn || !INSN_P (insn)
+ || GET_CODE (PATTERN (insn)) == USE
+ || GET_CODE (PATTERN (insn)) == CLOBBER)
+ return false;
+
+ if (rs6000_cpu == PROCESSOR_POWER4)
+ {
+ enum attr_type type = get_attr_type (insn);
+ if (type == TYPE_BRANCH || type == TYPE_JMPREG)
+ return true;
+ return false;
+ }
+
+ return false;
+}
/* A C statement (sans semicolon) to update the integer scheduling
priority INSN_PRIORITY (INSN). Increase the priority to execute the
case CPU_PPC604E:
case CPU_PPC620:
case CPU_PPC630:
- case CPU_POWER4:
return 4;
+ case CPU_POWER4:
+ return 5;
default:
return 1;
}
return false;
}
+/* Return the next insn after INSN that is found before TAIL is reached,
+ skipping any "non-active" insns - insns that will not actually occupy
+ an issue slot. Return NULL_RTX if such an insn is not found. */
+
+static rtx
+get_next_active_insn (rtx insn, rtx tail)
+{
+ rtx next_insn;
+
+ if (!insn || insn == tail)
+ return NULL_RTX;
+
+ next_insn = NEXT_INSN (insn);
+
+ while (next_insn
+ && next_insn != tail
+ && (GET_CODE(next_insn) == NOTE
+ || GET_CODE (PATTERN (next_insn)) == USE
+ || GET_CODE (PATTERN (next_insn)) == CLOBBER))
+ {
+ next_insn = NEXT_INSN (next_insn);
+ }
+
+ if (!next_insn || next_insn == tail)
+ return NULL_RTX;
+
+ return next_insn;
+}
+
+/* Return whether the presence of INSN causes a dispatch group terminatation
+ of group WHICH_GROUP.
+
+ If WHICH_GROUP == current_group, this function will return true if INSN
+ causes the termination of the current group (i.e, the dispatch group to
+ which INSN belongs). This means that INSN will be the last insn in the
+ group it belongs to.
+
+ If WHICH_GROUP == previous_group, this function will return true if INSN
+ causes the termination of the previous group (i.e, the dispatch group that
+ precedes the group to which INSN belongs). This means that INSN will be
+ the first insn in the group it belongs to). */
+
+static bool
+insn_terminates_group_p (rtx insn, enum group_termination which_group)
+{
+ enum attr_type type;
+
+ if (! insn)
+ return false;
+ type = get_attr_type (insn);
+
+ if (is_microcoded_insn (insn))
+ return true;
+
+ if (which_group == current_group)
+ {
+ if (is_branch_slot_insn (insn))
+ return true;
+ return false;
+ }
+ else if (which_group == previous_group)
+ {
+ if (is_dispatch_slot_restricted (insn))
+ return true;
+ return false;
+ }
+
+ return false;
+}
+
+/* Return true if it is recommended to keep NEXT_INSN "far" (in a seperate
+ dispatch group) from the insns in GROUP_INSNS. Return false otherwise. */
+
+static bool
+is_costly_group (rtx *group_insns, rtx next_insn)
+{
+ int i;
+ rtx link;
+ int cost;
+ int issue_rate = rs6000_issue_rate ();
+
+ for (i = 0; i < issue_rate; i++)
+ {
+ rtx insn = group_insns[i];
+ if (!insn)
+ continue;
+ for (link = INSN_DEPEND (insn); link != 0; link = XEXP (link, 1))
+ {
+ rtx next = XEXP (link, 0);
+ if (next == next_insn)
+ {
+ cost = insn_cost (insn, link, next_insn);
+ if (rs6000_is_costly_dependence (insn, next_insn, link, cost, 0))
+ return true;
+ }
+ }
+ }
+
+ return false;
+}
+
+/* Utility of the function redefine_groups.
+ Check if it is too costly to schedule NEXT_INSN together with GROUP_INSNS
+ in the same dispatch group. If so, insert nops before NEXT_INSN, in order
+ to keep it "far" (in a separate group) from GROUP_INSNS, following
+ one of the following schemes, depending on the value of the flag
+ -minsert_sched_nops = X:
+ (1) X == sched_finish_regroup_exact: insert exactly as many nops as needed
+ in order to force NEXT_INSN into a seperate group.
+ (2) X < sched_finish_regroup_exact: insert exactly X nops.
+ GROUP_END, CAN_ISSUE_MORE and GROUP_COUNT record the state after nop
+ insertion (has a group just ended, how many vacant issue slots remain in the
+ last group, and how many dispatch groups were encountered so far). */
+
+static int
+force_new_group (int sched_verbose, FILE *dump, rtx *group_insns, rtx next_insn,
+ bool *group_end, int can_issue_more, int *group_count)
+{
+ rtx nop;
+ bool force;
+ int issue_rate = rs6000_issue_rate ();
+ bool end = *group_end;
+ int i;
+
+ if (next_insn == NULL_RTX)
+ return can_issue_more;
+
+ if (rs6000_sched_insert_nops > sched_finish_regroup_exact)
+ return can_issue_more;
+
+ force = is_costly_group (group_insns, next_insn);
+ if (!force)
+ return can_issue_more;
+
+ if (sched_verbose > 6)
+ fprintf (dump,"force: group count = %d, can_issue_more = %d\n",
+ *group_count ,can_issue_more);
+
+ if (rs6000_sched_insert_nops == sched_finish_regroup_exact)
+ {
+ if (*group_end)
+ can_issue_more = 0;
+
+ /* Since only a branch can be issued in the last issue_slot, it is
+ sufficient to insert 'can_issue_more - 1' nops if next_insn is not
+ a branch. If next_insn is a branch, we insert 'can_issue_more' nops;
+ in this case the last nop will start a new group and the branch will be
+ forced to the new group. */
+ if (can_issue_more && !is_branch_slot_insn (next_insn))
+ can_issue_more--;
+
+ while (can_issue_more > 0)
+ {
+ nop = gen_nop();
+ emit_insn_before (nop, next_insn);
+ can_issue_more--;
+ }
+
+ *group_end = true;
+ return 0;
+ }
+
+ if (rs6000_sched_insert_nops < sched_finish_regroup_exact)
+ {
+ int n_nops = rs6000_sched_insert_nops;
+
+ /* Nops can't be issued from the branch slot, so the effective
+ issue_rate for nops is 'issue_rate - 1'. */
+ if (can_issue_more == 0)
+ can_issue_more = issue_rate;
+ can_issue_more--;
+ if (can_issue_more == 0)
+ {
+ can_issue_more = issue_rate - 1;
+ (*group_count)++;
+ end = true;
+ for (i = 0; i < issue_rate; i++)
+ {
+ group_insns[i] = 0;
+ }
+ }
+
+ while (n_nops > 0)
+ {
+ nop = gen_nop ();
+ emit_insn_before (nop, next_insn);
+ if (can_issue_more == issue_rate - 1) /* new group begins */
+ end = false;
+ can_issue_more--;
+ if (can_issue_more == 0)
+ {
+ can_issue_more = issue_rate - 1;
+ (*group_count)++;
+ end = true;
+ for (i = 0; i < issue_rate; i++)
+ {
+ group_insns[i] = 0;
+ }
+ }
+ n_nops--;
+ }
+
+ /* Scale back relative to 'issue_rate' (instead of 'issue_rate - 1'). */
+ can_issue_more++;
+
+ *group_end = /* Is next_insn going to start a new group? */
+ (end
+ || (can_issue_more == 1 && !is_branch_slot_insn (next_insn))
+ || (can_issue_more <= 2 && is_cracked_insn (next_insn))
+ || (can_issue_more < issue_rate &&
+ insn_terminates_group_p (next_insn, previous_group)));
+ if (*group_end && end)
+ (*group_count)--;
+
+ if (sched_verbose > 6)
+ fprintf (dump, "done force: group count = %d, can_issue_more = %d\n",
+ *group_count, can_issue_more);
+ return can_issue_more;
+ }
+
+ return can_issue_more;
+}
+
+/* This function tries to synch the dispatch groups that the compiler "sees"
+ with the dispatch groups that the processor dispatcher is expected to
+ form in practice. It tries to achieve this synchronization by forcing the
+ estimated processor grouping on the compiler (as opposed to the function
+ 'pad_goups' which tries to force the scheduler's grouping on the processor).
+
+ The function scans the insn sequence between PREV_HEAD_INSN and TAIL and
+ examines the (estimated) dispatch groups that will be formed by the processor
+ dispatcher. It marks these group boundaries to reflect the estimated
+ processor grouping, overriding the grouping that the scheduler had marked.
+ Depending on the value of the flag '-minsert-sched-nops' this function can
+ force certain insns into separate groups or force a certain distance between
+ them by inserting nops, for example, if there exists a "costly dependence"
+ between the insns.
+
+ The function estimates the group boundaries that the processor will form as
+ folllows: It keeps track of how many vacant issue slots are available after
+ each insn. A subsequent insn will start a new group if one of the following
+ 4 cases applies:
+ - no more vacant issue slots remain in the current dispatch group.
+ - only the last issue slot, which is the branch slot, is vacant, but the next
+ insn is not a branch.
+ - only the last 2 or less issue slots, including the branch slot, are vacant,
+ which means that a cracked insn (which occupies two issue slots) can't be
+ issued in this group.
+ - less than 'issue_rate' slots are vacant, and the next insn always needs to
+ start a new group. */
+
+static int
+redefine_groups (FILE *dump, int sched_verbose, rtx prev_head_insn, rtx tail)
+{
+ rtx insn, next_insn;
+ int issue_rate;
+ int can_issue_more;
+ int slot, i;
+ bool group_end;
+ int group_count = 0;
+ rtx *group_insns;
+
+ /* Initialize. */
+ issue_rate = rs6000_issue_rate ();
+ group_insns = alloca (issue_rate * sizeof (rtx));
+ for (i = 0; i < issue_rate; i++)
+ {
+ group_insns[i] = 0;
+ }
+ can_issue_more = issue_rate;
+ slot = 0;
+ insn = get_next_active_insn (prev_head_insn, tail);
+ group_end = false;
+
+ while (insn != NULL_RTX)
+ {
+ slot = (issue_rate - can_issue_more);
+ group_insns[slot] = insn;
+ can_issue_more =
+ rs6000_variable_issue (dump, sched_verbose, insn, can_issue_more);
+ if (insn_terminates_group_p (insn, current_group))
+ can_issue_more = 0;
+
+ next_insn = get_next_active_insn (insn, tail);
+ if (next_insn == NULL_RTX)
+ return group_count + 1;
+
+ group_end = /* Is next_insn going to start a new group? */
+ (can_issue_more == 0
+ || (can_issue_more == 1 && !is_branch_slot_insn (next_insn))
+ || (can_issue_more <= 2 && is_cracked_insn (next_insn))
+ || (can_issue_more < issue_rate &&
+ insn_terminates_group_p (next_insn, previous_group)));
+
+ can_issue_more = force_new_group (sched_verbose, dump, group_insns,
+ next_insn, &group_end, can_issue_more, &group_count);
+
+ if (group_end)
+ {
+ group_count++;
+ can_issue_more = 0;
+ for (i = 0; i < issue_rate; i++)
+ {
+ group_insns[i] = 0;
+ }
+ }
+
+ if (GET_MODE (next_insn) == TImode && can_issue_more)
+ PUT_MODE(next_insn, VOIDmode);
+ else if (!can_issue_more && GET_MODE (next_insn) != TImode)
+ PUT_MODE (next_insn, TImode);
+
+ insn = next_insn;
+ if (can_issue_more == 0)
+ can_issue_more = issue_rate;
+ } /* while */
+
+ return group_count;
+}
+
+/* Scan the insn sequence between PREV_HEAD_INSN and TAIL and examine the
+ dispatch group boundaries that the scheduler had marked. Pad with nops
+ any dispatch groups which have vacant issue slots, in order to force the
+ scheduler's grouping on the processor dispatcher. The function
+ returns the number of dispatch groups found. */
+
+static int
+pad_groups (FILE *dump, int sched_verbose, rtx prev_head_insn, rtx tail)
+{
+ rtx insn, next_insn;
+ rtx nop;
+ int issue_rate;
+ int can_issue_more;
+ int group_end;
+ int group_count = 0;
+
+ /* Initialize issue_rate. */
+ issue_rate = rs6000_issue_rate ();
+ can_issue_more = issue_rate;
+
+ insn = get_next_active_insn (prev_head_insn, tail);
+ next_insn = get_next_active_insn (insn, tail);
+
+ while (insn != NULL_RTX)
+ {
+ can_issue_more =
+ rs6000_variable_issue (dump, sched_verbose, insn, can_issue_more);
+
+ group_end = (next_insn == NULL_RTX || GET_MODE (next_insn) == TImode);
+
+ if (next_insn == NULL_RTX)
+ break;
+
+ if (group_end)
+ {
+ /* If the scheduler had marked group termination at this location
+ (between insn and next_indn), and neither insn nor next_insn will
+ force group termination, pad the group with nops to force group
+ termination. */
+ if (can_issue_more
+ && (rs6000_sched_insert_nops == sched_finish_pad_groups)
+ && !insn_terminates_group_p (insn, current_group)
+ && !insn_terminates_group_p (next_insn, previous_group))
+ {
+ if (!is_branch_slot_insn(next_insn))
+ can_issue_more--;
+
+ while (can_issue_more)
+ {
+ nop = gen_nop ();
+ emit_insn_before (nop, next_insn);
+ can_issue_more--;
+ }
+ }
+
+ can_issue_more = issue_rate;
+ group_count++;
+ }
+
+ insn = next_insn;
+ next_insn = get_next_active_insn (insn, tail);
+ }
+
+ return group_count;
+}
+
+/* The following function is called at the end of scheduling BB.
+ After reload, it inserts nops at insn group bundling. */
+
+static void
+rs6000_sched_finish (dump, sched_verbose)
+ FILE *dump;
+ int sched_verbose;
+{
+ int n_groups;
+
+ if (sched_verbose)
+ fprintf (dump, "=== Finishing schedule.\n");
+
+ if (reload_completed && rs6000_cpu == PROCESSOR_POWER4)
+ {
+ if (rs6000_sched_insert_nops == sched_finish_none)
+ return;
+
+ if (rs6000_sched_insert_nops == sched_finish_pad_groups)
+ n_groups = pad_groups (dump, sched_verbose,
+ current_sched_info->prev_head,
+ current_sched_info->next_tail);
+ else
+ n_groups = redefine_groups (dump, sched_verbose,
+ current_sched_info->prev_head,
+ current_sched_info->next_tail);
+
+ if (sched_verbose >= 6)
+ {
+ fprintf (dump, "ngroups = %d\n", n_groups);
+ print_rtl (dump, current_sched_info->prev_head);
+ fprintf (dump, "Done finish_sched\n");
+ }
+ }
+}
\f
/* Length in units of the trampoline for entering a nested function. */
projects / platform / upstream / linaro-gcc.git / commitdiff