Happier cache lines.

Probably the only change that actually affects something, `struct ir_state` is both important and now fits within a single cache line.

I did this by eyeballing:
```
; bmake -r -j 10 CC=clang DEBUG=1 && (for t in `cat /tmp/tags`; do pahole --class_name $t build/src/*/*.o build/src/adt/*.o ; done ) > /tmp/tt
```

This gives a ~2% improvement on total execution for rx -q /usr/share/bin/words

src/adt/edgeset.c

@@ -35,8 +35,8 @@ struct edge_set {
 	size_t ceil;		/* nonzero */
 	size_t count;		/* <= ceil */
 	struct edge_group {
-		fsm_state_t to;	/* distinct */
 		uint64_t symbols[256/64];
+		fsm_state_t to;	/* distinct */
 	} *groups;		/* sorted by .to */
 };
 

src/libfsm/clone.c

@@ -7,6 +7,7 @@
 #include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include <stdbool.h>
 
 #include <fsm/fsm.h>
 #include <fsm/pred.h>
@@ -86,7 +87,7 @@ fsm_clone(const struct fsm *fsm)
 
 struct copy_capture_actions_env {
 	struct fsm *dst;
-	int ok;
+	bool ok;
 };
 
 static int
@@ -99,7 +100,7 @@ copy_capture_actions_cb(fsm_state_t state,
 
 	if (!fsm_capture_add_action(env->dst,
 		state, type, capture_id, to)) {
-		env->ok = 0;
+		env->ok = false;
 	}
 
 	return env->ok;
@@ -108,7 +109,7 @@ copy_capture_actions_cb(fsm_state_t state,
 static int
 copy_capture_actions(struct fsm *dst, const struct fsm *src)
 {
-	struct copy_capture_actions_env env = { NULL, 1 };
+	struct copy_capture_actions_env env = { NULL, true };
 	env.dst = dst;
 
 	fsm_capture_action_iter(src,
@@ -120,7 +121,7 @@ struct copy_end_ids_env {
 	char tag;
 	struct fsm *dst;
 	const struct fsm *src;
-	int ok;
+	bool ok;
 };
 
 static int
@@ -134,7 +135,7 @@ copy_end_ids_cb(fsm_state_t state, const fsm_end_id_t id, void *opaque)
 #endif
 
 	if (!fsm_endid_set(env->dst, state, id)) {
-		env->ok = 0;
+		env->ok = false;
 		return 0;
 	}
 
@@ -148,7 +149,7 @@ copy_end_ids(struct fsm *dst, const struct fsm *src)
 	env.tag = 'c';		/* for clone */
 	env.dst = dst;
 	env.src = src;
-	env.ok = 1;
+	env.ok = true;
 
 	fsm_endid_iter(src, copy_end_ids_cb, &env);
 

src/libfsm/consolidate.c

@@ -9,6 +9,7 @@
 #include <assert.h>
 #include <stddef.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <stdio.h>
 
 #include <fsm/fsm.h>
@@ -39,7 +40,7 @@ struct consolidate_copy_capture_actions_env {
 	struct fsm *dst;
 	size_t mapping_count;
 	const fsm_state_t *mapping;
-	int ok;
+	bool ok;
 };
 
 static int
@@ -186,7 +187,7 @@ consolidate_copy_capture_actions_cb(fsm_state_t state,
 
 	if (!fsm_capture_add_action(env->dst,
 		s, type, capture_id, t)) {
-		env->ok = 0;
+		env->ok = false;
 		return 0;
 	}
 
@@ -204,7 +205,7 @@ consolidate_copy_capture_actions(struct fsm *dst, const struct fsm *src,
 	env.dst = dst;
 	env.mapping_count = mapping_count;
 	env.mapping = mapping;
-	env.ok = 1;
+	env.ok = true;
 
 #if LOG_MAPPING
 	for (i = 0; i < mapping_count; i++) {

src/libfsm/determinise_internal.h

@@ -3,6 +3,7 @@
 
 #include <assert.h>
 #include <stddef.h>
+#include <stdbool.h>
 #include <string.h>
 #include <errno.h>
 
@@ -85,7 +86,7 @@ struct det_copy_capture_actions_env {
 	char tag;
 	struct fsm *dst;
 	struct reverse_mapping *reverse_mappings;
-	int ok;
+	bool ok;
 };
 
 #define MAPPINGSTACK_DEF_CEIL 16

src/libfsm/endids.c

@@ -5,6 +5,7 @@
  */
 
 #include <stddef.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <inttypes.h>
 
@@ -755,7 +756,7 @@ struct carry_env {
 	char tag;
 	struct fsm *dst;
 	fsm_state_t dst_state;
-	int ok;
+	bool ok;
 };
 
 static int
@@ -767,7 +768,7 @@ carry_iter_cb(fsm_state_t state, fsm_end_id_t id, void *opaque)
 	(void)state;
 
 	if (!fsm_endid_set(env->dst, env->dst_state, id)) {
-		env->ok = 0;
+		env->ok = false;
 		return 0;
 	}
 	return 1;
@@ -798,7 +799,7 @@ fsm_endid_carry(const struct fsm *src_fsm, const struct state_set *src_set,
 		env.tag = 'C';
 		env.dst = dst_fsm;
 		env.dst_state = dst_state;
-		env.ok = 1;
+		env.ok = true;
 
 		if (!fsm_isend(src_fsm, s)) {
 			continue;

src/libfsm/epsilons.c

@@ -7,6 +7,7 @@
 #include <assert.h>
 #include <stddef.h>
 #include <stdio.h>
+#include <stdbool.h>
 #include <errno.h>
 
 #include <fsm/fsm.h>
@@ -28,9 +29,9 @@
 
 struct remap_env {
 	char tag;
+	bool ok;
 	const struct fsm_alloc *alloc;
 	struct state_set **rmap;
-	int ok;
 
 	size_t count;
 	size_t ceil;
@@ -182,7 +183,7 @@ remap_capture_actions(struct fsm *nfa, struct state_set **eclosures)
 	struct state_set **rmap;
 	struct state_iter si;
 	fsm_state_t si_s;
-	struct remap_env env = { 'R', NULL, NULL, 1, 0, 0, NULL };
+	struct remap_env env = { 'R', true, NULL, NULL, 0, 0, NULL };
 	env.alloc = nfa->alloc;
 
 	/* build a reverse mapping */
@@ -325,17 +326,17 @@ remap_capture_action_cb(fsm_state_t state,
 	return 1;
 
 fail:
-	env->ok = 0;
+	env->ok = false;
 	return 0;
 }
 
 struct collect_env {
 	char tag;
+	bool ok;
 	const struct fsm_alloc *alloc;
 	size_t count;
 	size_t ceil;
 	fsm_end_id_t *ids;
-	int ok;
 };
 
 static int
@@ -353,7 +354,7 @@ collect_cb(fsm_state_t state, fsm_end_id_t id, void *opaque)
 		nids = f_realloc(env->alloc, env->ids,
 		    nceil * sizeof(*env->ids));
 		if (nids == NULL) {
-			env->ok = 0;
+			env->ok = false;
 			return 0;
 		}
 		env->ceil = nceil;
@@ -390,7 +391,7 @@ carry_endids(struct fsm *fsm, struct state_set *states,
 	if (env.ids == NULL) {
 		return 0;
 	}
-	env.ok = 1;
+	env.ok = true;
 
 	/* collect from states */
 	for (state_set_reset(states, &it); state_set_next(&it, &s); ) {
@@ -407,7 +408,7 @@ carry_endids(struct fsm *fsm, struct state_set *states,
 	/* add them */
 	for (i = 0; i < env.count; i++) {
 		if (!fsm_endid_set(fsm, dst_state, env.ids[i])) {
-			env.ok = 0;
+			env.ok = false;
 			goto cleanup;
 		}
 	}

src/libfsm/gen.c

@@ -74,22 +74,24 @@ struct gen_ctx {
 	const struct fsm *fsm;
 	size_t max_length;
 	fsm_generate_matches_cb *cb;
-	void *opaque;
+
+	bool done;
 
 	size_t buf_ceil;
 	size_t buf_used;
 	char *buf;
 
+	void *opaque;
+
+	unsigned depth;
+	unsigned steps;
+
 	/* This is used to avoid useless cycles -- if a state
 	 * was reached since the same match_count, then don't
 	 * explore it again. */
 	unsigned match_count;
 	unsigned *state_counts;
 
-	unsigned depth;
-	unsigned steps;
-	bool done;
-
 	/* Shortest end distance for a state: sed[s_id] */
 	unsigned *sed;
 

src/libfsm/internal.h

@@ -44,11 +44,14 @@ struct state_array;
 #define FSM_CAPTURE_MAX INT_MAX
 
 struct fsm_edge {
-	fsm_state_t state; /* destination */
+	fsm_state_t state:24; /* destination. :24 for packing */
 	unsigned char symbol;
 };
 
 struct fsm_state {
+	struct edge_set *edges;
+	struct state_set *epsilons;
+
 	unsigned int end:1;
 
 	/* If 0, then this state has no need for checking
@@ -57,9 +60,6 @@ struct fsm_state {
 
 	/* meaningful within one particular transformation only */
 	unsigned int visited:1;
-
-	struct edge_set *edges;
-	struct state_set *epsilons;
 };
 
 struct fsm {
@@ -68,10 +68,10 @@ struct fsm {
 
 	size_t statealloc; /* number of elements allocated */
 	size_t statecount; /* number of elements populated */
-	size_t endcount;
+	size_t endcount:31; /* :31 for packing */
 
-	fsm_state_t start;
 	unsigned int hasstart:1;
+	fsm_state_t start;
 
 	struct fsm_capture_info *capture_info;
 	struct endid_info *endid_info;

src/libfsm/merge.c

@@ -27,8 +27,8 @@
 
 struct copy_capture_env {
 	char tag;
+	bool ok;
 	struct fsm *dst;
-	int ok;
 };
 
 static int
@@ -134,7 +134,7 @@ copy_capture_cb(fsm_state_t state,
 
 	if (!fsm_capture_add_action(env->dst, state, type,
 		capture_id, to)) {
-		env->ok = 0;
+		env->ok = false;
 		return 0;
 	}
 
@@ -147,7 +147,7 @@ copy_capture_actions(struct fsm *dst, struct fsm *src)
 	struct copy_capture_env env;
 	env.tag = 'C';
 	env.dst = dst;
-	env.ok = 1;
+	env.ok = true;
 
 	fsm_capture_action_iter(src, copy_capture_cb, &env);
 

src/libfsm/print.c

@@ -354,7 +354,7 @@ fsm_print(FILE *f, const struct fsm *fsm,
 				continue;
 			}
 
-			assert(ir->states[i].endids.count <= 1);
+			assert(ir->states[i].count <= 1);
 		}
 	}
 

src/libfsm/print/c.c

@@ -375,15 +375,15 @@ print_endstates(FILE *f,
 		fprintf(f, "\tcase S%u: ", i);
 
 		if (-1 == print_hook_accept(f, opt, hooks,
-			ir->states[i].endids.ids, ir->states[i].endids.count,
+			ir->states[i].ids, ir->states[i].count,
 			default_accept,
 			NULL))
 		{
 			return -1;
 		}
 
 		if (-1 == print_hook_comment(f, opt, hooks,
-			ir->states[i].endids.ids, ir->states[i].endids.count))
+			ir->states[i].ids, ir->states[i].count))
 		{
 			return -1;
 		}

src/libfsm/print/ir.c

@@ -541,8 +541,8 @@ make_ir(const struct fsm *fsm, const struct fsm_options *opt)
 		assert(i < ir->n);
 
 		ir->states[i].isend  = fsm_isend(fsm, i);
-		ir->states[i].endids.ids = NULL;
-		ir->states[i].endids.count = 0;
+		ir->states[i].ids = NULL;
+		ir->states[i].count = 0;
 
 		if (fsm_isend(fsm, i)) {
 			fsm_end_id_t *ids;
@@ -563,8 +563,8 @@ make_ir(const struct fsm *fsm, const struct fsm_options *opt)
 				assert(res == 1);
 			}
 
-			ir->states[i].endids.ids = ids;
-			ir->states[i].endids.count = count;
+			ir->states[i].ids = ids;
+			ir->states[i].count = count;
 		}
 
 		if (make_state(fsm, i, &ir->states[i]) == -1) {
@@ -629,7 +629,7 @@ free_ir(const struct fsm *fsm, struct ir *ir)
 
 	for (i = 0; i < ir->n; i++) {
 		f_free(fsm->alloc, (void *) ir->states[i].example);
-		f_free(fsm->alloc, (void *) ir->states[i].endids.ids);
+		f_free(fsm->alloc, (void *) ir->states[i].ids);
 
 		switch (ir->states[i].strategy) {
 		case IR_TABLE: