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optimizer: fix reordering in let+values+values splitting

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While the commit comment in 3150b31eb7 still seems right, the changed
overlooked the fact that the arguments to a split `values` might get
reordered (due to the way binding positions are calculated). Fix the
optimizer to make sure that reordering is allowed.

The change touches a lot of code, because we want to use
"omittable" to implement "movable", and it's not ok to
reorder access of mutable variables (in case some other thread is
mutating them). We have to fix all the calls to "omittable"
to support the slight generalization.
This commit is contained in:
Matthew Flatt 2014-06-20 07:56:16 +01:00
parent da979b6c8d
commit 16a0727231
7 changed files with 129 additions and 59 deletions
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23
pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
View File

@ -1509,6 +1509,29 @@
(let ([f (lambda () f)]) f))])
(car f))
;; Make sure `values` splitting doesn't reorder expressions
(let ([f (lambda (z)
(let-values ([(a b) (values (list (z 1)) (list (z 2)))])
(list a b)))])
(set! f f)
(let ([v 0])
(test '((1) (2)) f (lambda (n) (set! v n) n))
(test 2 values v)))
(test-comp '(lambda (z)
;; ok to reorder `(list z)` and `(list (z 2))`,
;; which then allows more simplication:
(let-values ([(a b) (values (list z) (list (z 2)))])
(list a b)))
'(lambda (z)
(list (list z) (list (z 2)))))
(test-comp '(lambda (z)
(let-values ([(a b) (values (list (z 2)) (list z))])
(list a b)))
'(lambda (z)
(let ([p (list z)])
(list (list (z 2)) p))))
(test-comp '(let-values ([(x y) (values 1 2)])
(+ x y))
3)

8
racket/src/racket/src/compile.c
View File

@ -2948,7 +2948,7 @@ Scheme_Object *scheme_make_sequence_compilation(Scheme_Object *seq, int opt)
total++;
} else if (opt
&& (((opt > 0) && !last) || ((opt < 0) && !first))
&& scheme_omittable_expr(v, -1, -1, 0, NULL, NULL, -1, 1)) {
&& scheme_omittable_expr(v, -1, -1, 0, NULL, NULL, 0, 0, 1)) {
/* A value that is not the result. We'll drop it. */
total++;
} else {
@ -2976,7 +2976,7 @@ Scheme_Object *scheme_make_sequence_compilation(Scheme_Object *seq, int opt)
/* can't optimize away a begin0 at read time; it's too late, since the
return is combined with EXPD_BEGIN0 */
addconst = 1;
} else if ((opt < 0) && !scheme_omittable_expr(SCHEME_CAR(seq), 1, -1, 0, NULL, NULL, -1, 1)) {
} else if ((opt < 0) && !scheme_omittable_expr(SCHEME_CAR(seq), 1, -1, 0, NULL, NULL, 0, 0, 1)) {
/* We can't optimize (begin0 expr cont) to expr because
exp is not in tail position in the original (so we'd mess
up continuation marks). */
@ -3008,7 +3008,7 @@ Scheme_Object *scheme_make_sequence_compilation(Scheme_Object *seq, int opt)
} else if (opt
&& (((opt > 0) && (k < total))
|| ((opt < 0) && k))
&& scheme_omittable_expr(v, -1, -1, 0, NULL, NULL, -1, 1)) {
&& scheme_omittable_expr(v, -1, -1, 0, NULL, NULL, 0, 0, 1)) {
/* Value not the result. Do nothing. */
} else
o->array[i++] = v;
@ -3511,7 +3511,7 @@ static Scheme_Object *eval_letmacro_rhs(Scheme_Object *a, Scheme_Comp_Env *rhs_e
save_runstack = scheme_push_prefix(NULL, rp, NULL, NULL, phase, phase, rhs_env->genv, NULL);
if (scheme_omittable_expr(a, 1, -1, 0, NULL, NULL, -1, 0)) {
if (scheme_omittable_expr(a, 1, -1, 0, NULL, NULL, 0, 0, 0)) {
/* short cut */
a = _scheme_eval_linked_expr_multi(a);
} else {

2
racket/src/racket/src/module.c
View File

@ -9455,7 +9455,7 @@ static Scheme_Object *do_module_begin_at_phase(Scheme_Object *form, Scheme_Comp_
Scheme_Object *prev = NULL, *next;
for (p = first; !SCHEME_NULLP(p); p = next) {
next = SCHEME_CDR(p);
if (scheme_omittable_expr(SCHEME_CAR(p), -1, -1, 0, NULL, NULL, -1, 0)) {
if (scheme_omittable_expr(SCHEME_CAR(p), -1, -1, 0, NULL, NULL, 0, 0, 0)) {
if (prev)
SCHEME_CDR(prev) = next;
else

146
racket/src/racket/src/optimize.c
View File

@ -137,6 +137,10 @@ static int movable_expression(Scheme_Object *expr, Optimize_Info *info, int delt
int cross_lambda, int cross_k,
int check_space, int fuel);
#define ID_OMIT 0
#define NO_ID_OMIT 1
#define NO_MUTABLE_ID_OMIT -1
#define IS_COMPILED_PROC(vals_expr) (SAME_TYPE(SCHEME_TYPE(vals_expr), scheme_compiled_unclosed_procedure_type) \
|| SAME_TYPE(SCHEME_TYPE(vals_expr), scheme_case_lambda_sequence_type))
@ -249,18 +253,28 @@ static void note_match(int actual, int expected, Optimize_Info *warn_info)
}
int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
Optimize_Info *opt_info, Optimize_Info *warn_info, int deeper_than, int no_id)
Optimize_Info *opt_info, Optimize_Info *warn_info,
int min_id_depth, int id_offset, int no_id)
/* Checks whether the bytecode `o' returns `vals' values with no
side-effects and without pushing and using continuation marks.
-1 for vals means that any return count is ok.
Also used with fully resolved expression by `module' to check
for "functional" bodies.
If warn_info is supplied, complain when a mismatch is detected.
If no_id is 1, then an identifier doesn't count as omittable,
The min_id_depth argument (plus id_ofset) indicates the minimum
depth allowed for local-variable reference; use this to disallow
access to the first N variables that represent bindings being set up,
for example.
The id_offset value indincates an offset for local variables relative
to opt_info; id_offset is also implicitly added to min_id_depth.
If no_id is NO_ID_OMIT (= 1), then an identifier doesn't count as omittable,
unless the identifier is a consistent top-level; the no_id mode
is used by the "compile" phase before letrec checks are inserted
(where referencing a variable might raise an exception) and to
imply the absence of a continuation-mark impersonator. */
imply the absence of a continuation-mark impersonator.
If no_id is NO_MUTABLE_ID_OMIT (= -1), then an identifier doesn't
count as omittable if it's mutable, because the expression may be reordered
instead of omitted; opt_info must be provided to check mutability. */
{
Scheme_Type vtype;
@ -272,13 +286,14 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
if ((vtype > _scheme_compiled_values_types_)
|| ((vtype == scheme_local_type)
&& !no_id
&& (no_id <= 0)
&& !(SCHEME_GET_LOCAL_FLAGS(o) == SCHEME_LOCAL_CLEAR_ON_READ)
&& (SCHEME_LOCAL_POS(o) > deeper_than))
&& (SCHEME_LOCAL_POS(o) >= (min_id_depth + id_offset))
&& (!no_id || !optimize_is_mutated(opt_info, SCHEME_LOCAL_POS(o) - id_offset)))
|| ((vtype == scheme_local_unbox_type)
&& !no_id
&& !(SCHEME_GET_LOCAL_FLAGS(o) == SCHEME_LOCAL_CLEAR_ON_READ)
&& (SCHEME_LOCAL_POS(o) > deeper_than))
&& (SCHEME_LOCAL_POS(o) >= (min_id_depth + id_offset)))
|| (vtype == scheme_unclosed_procedure_type)
|| (vtype == scheme_compiled_unclosed_procedure_type)
|| (vtype == scheme_inline_variant_type)
@ -325,9 +340,9 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
if (vtype == scheme_branch_type) {
Scheme_Branch_Rec *b;
b = (Scheme_Branch_Rec *)o;
return (scheme_omittable_expr(b->test, 1, fuel - 1, resolved, opt_info, warn_info, deeper_than, no_id)
&& scheme_omittable_expr(b->tbranch, vals, fuel - 1, resolved, opt_info, warn_info, deeper_than, no_id)
&& scheme_omittable_expr(b->fbranch, vals, fuel - 1, resolved, opt_info, warn_info, deeper_than, no_id));
return (scheme_omittable_expr(b->test, 1, fuel - 1, resolved, opt_info, warn_info, min_id_depth, id_offset, no_id)
&& scheme_omittable_expr(b->tbranch, vals, fuel - 1, resolved, opt_info, warn_info, min_id_depth, id_offset, no_id)
&& scheme_omittable_expr(b->fbranch, vals, fuel - 1, resolved, opt_info, warn_info, min_id_depth, id_offset, no_id));
}
#if 0
@ -335,15 +350,15 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
a let_value_type! */
if (vtype == scheme_let_value_type) {
Scheme_Let_Value *lv = (Scheme_Let_Value *)o;
return (scheme_omittable_expr(lv->value, lv->count, fuel - 1, resolved, opt_info, warn_info, deeper_than, no_id)
&& scheme_omittable_expr(lv->body, vals, fuel - 1, resolved, opt_info, warn_info, deeper_than, no_id));
return (scheme_omittable_expr(lv->value, lv->count, fuel - 1, resolved, opt_info, warn_info, min_id_depth, id_offset, no_id)
&& scheme_omittable_expr(lv->body, vals, fuel - 1, resolved, opt_info, warn_info, min_id_depth, id_offset, no_id));
}
#endif
if (vtype == scheme_let_one_type) {
Scheme_Let_One *lo = (Scheme_Let_One *)o;
return (scheme_omittable_expr(lo->value, 1, fuel - 1, resolved, opt_info, warn_info, deeper_than + 1, 0)
&& scheme_omittable_expr(lo->body, vals, fuel - 1, resolved, opt_info, warn_info, deeper_than + 1, no_id));
return (scheme_omittable_expr(lo->value, 1, fuel - 1, resolved, opt_info, warn_info, min_id_depth, id_offset + 1, no_id)
&& scheme_omittable_expr(lo->body, vals, fuel - 1, resolved, opt_info, warn_info, min_id_depth, id_offset + 1, no_id));
}
if (vtype == scheme_let_void_type) {
@ -354,15 +369,15 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
if ((lv2->count == 1)
&& (lv2->position == 0)
&& scheme_omittable_expr(lv2->value, 1, fuel - 1, resolved, opt_info, warn_info,
deeper_than + 1 + lv->count,
min_id_depth, id_offset + 1 + lv->count,
no_id)) {
o = lv2->body;
deeper_than += 1;
id_offset += 1;
} else
o = lv->body;
} else
o = lv->body;
deeper_than += lv->count;
id_offset += lv->count;
goto try_again;
}
@ -372,9 +387,9 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
if ((lh->count == 1) && (lh->num_clauses == 1)) {
if (SAME_TYPE(SCHEME_TYPE(lh->body), scheme_compiled_let_value_type)) {
Scheme_Compiled_Let_Value *lv = (Scheme_Compiled_Let_Value *)lh->body;
if (scheme_omittable_expr(lv->value, 1, fuel - 1, resolved, opt_info, warn_info, deeper_than + 1, no_id)) {
if (scheme_omittable_expr(lv->value, 1, fuel - 1, resolved, opt_info, warn_info, min_id_depth, id_offset + 1, no_id)) {
o = lv->body;
deeper_than++;
id_offset++;
goto try_again;
}
}
@ -399,7 +414,7 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
int i;
for (i = app->num_args; i--; ) {
if (!scheme_omittable_expr(app->args[i + 1], 1, fuel - 1, resolved, opt_info, warn_info,
deeper_than + (resolved ? app->num_args : 0), no_id))
min_id_depth, id_offset + (resolved ? app->num_args : 0), no_id))
return 0;
}
return 1;
@ -419,7 +434,7 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
if (scheme_is_functional_nonfailing_primitive(app->rator, 1, vals)
|| scheme_is_struct_functional(app->rator, 1, opt_info, vals)) {
if (scheme_omittable_expr(app->rand, 1, fuel - 1, resolved, opt_info, warn_info,
deeper_than + (resolved ? 1 : 0), no_id))
min_id_depth, id_offset + (resolved ? 1 : 0), no_id))
return 1;
} else if (SCHEME_PRIMP(app->rator)) {
if (!(SCHEME_PRIM_PROC_FLAGS(app->rator) & SCHEME_PRIM_IS_MULTI_RESULT)
@ -435,9 +450,9 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
if (scheme_is_functional_nonfailing_primitive(app->rator, 2, vals)
|| scheme_is_struct_functional(app->rator, 2, opt_info, vals)) {
if (scheme_omittable_expr(app->rand1, 1, fuel - 1, resolved, opt_info, warn_info,
deeper_than + (resolved ? 2 : 0), no_id)
min_id_depth, id_offset + (resolved ? 2 : 0), no_id)
&& scheme_omittable_expr(app->rand2, 1, fuel - 1, resolved, opt_info, warn_info,
deeper_than + (resolved ? 2 : 0), no_id))
min_id_depth, id_offset + (resolved ? 2 : 0), no_id))
return 1;
} else if (SCHEME_PRIMP(app->rator)) {
if (!(SCHEME_PRIM_PROC_FLAGS(app->rator) & SCHEME_PRIM_IS_MULTI_RESULT)) {
@ -469,7 +484,7 @@ int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
5);
if (auto_e) {
if (scheme_omittable_expr(auto_e, 1, fuel - 1, resolved, opt_info, warn_info,
deeper_than + auto_e_depth, no_id))
min_id_depth, id_offset + auto_e_depth, no_id))
return 1;
}
}
@ -499,12 +514,12 @@ static Scheme_Object *do_make_discarding_sequence(Scheme_Object *e1, Scheme_Obje
{
int e2_omit;
e2_omit = scheme_omittable_expr(e2, 1, 5, 0, info, NULL, -1, 0);
e2_omit = scheme_omittable_expr(e2, 1, 5, 0, info, NULL, 0, 0, ID_OMIT);
if (!e2_omit && !single_valued_noncm_expression(e2, 5))
e2 = ensure_single_value(e2);
if (scheme_omittable_expr(e1, 1, 5, 0, info, NULL, -1, 0))
if (scheme_omittable_expr(e1, 1, 5, 0, info, NULL, 0, 0, ID_OMIT))
return e2;
else if (single_valued_noncm_expression(e1, 5))
e1 = optimize_ignored(e1, info, 1, 0, 5);
@ -550,7 +565,7 @@ static Scheme_Object *make_discarding_app_sequence(Scheme_App_Rec *appr, int res
for (i = appr->num_args; i; i--) {
e = appr->args[i];
if (scheme_omittable_expr(e, 1, 5, 0, info, NULL, -1, 0)) {
if (scheme_omittable_expr(e, 1, 5, 0, info, NULL, 0, 0, ID_OMIT)) {
/* drop if not result pos */
} else if (single_valued_noncm_expression(e, 5)) {
if (i != result_pos) {
@ -589,7 +604,7 @@ static Scheme_Object *optimize_ignored(Scheme_Object *e, Optimize_Info *info, in
NULL to dincate that it can be omitted. */
{
if (maybe_omittable) {
if (scheme_omittable_expr(e, expected_vals, 5, 0, info, NULL, -1, 0))
if (scheme_omittable_expr(e, expected_vals, 5, 0, info, NULL, 0, 0, ID_OMIT))
return NULL;
}
@ -933,7 +948,7 @@ Scheme_Object *scheme_is_simple_make_struct_type(Scheme_Object *e, int vals, int
&& ((app->num_args < 5)
/* auto-field value: */
|| !check_auto
|| scheme_omittable_expr(app->args[5], 1, 3, resolved, NULL, NULL, -1, 0))
|| scheme_omittable_expr(app->args[5], 1, 3, resolved, NULL, NULL, 0, 0, ID_OMIT))
&& ((app->num_args < 6)
/* no properties: */
|| SCHEME_NULLP(app->args[6]))
@ -2830,7 +2845,7 @@ static Scheme_Object *finish_optimize_application2(Scheme_App2_Rec *app, Optimiz
if ((SAME_OBJ(scheme_values_func, app->rator)
|| SAME_OBJ(scheme_list_star_proc, app->rator))
&& (scheme_omittable_expr(app->rand, 1, -1, 0, info, info, -1, 0)
&& (scheme_omittable_expr(app->rand, 1, -1, 0, info, info, 0, 0, ID_OMIT)
|| single_valued_noncm_expression(app->rand, 5))) {
info->preserves_marks = 1;
info->single_result = 1;
@ -3722,8 +3737,8 @@ static Scheme_Object *optimize_branch(Scheme_Object *o, Optimize_Info *info, int
static int omittable_key(Scheme_Object *k, Optimize_Info *info)
{
/* A key is not omittable if it might refer to a chaperoned/impersonated
continuation mark key, so that's why we pass 1 for `no_id': */
return scheme_omittable_expr(k, 1, 20, 0, info, info, -1, 1);
continuation mark key, so that's why we pass NO_ID_OMIT: */
return scheme_omittable_expr(k, 1, 20, 0, info, info, 0, 0, NO_ID_OMIT);
}
static Scheme_Object *optimize_wcm(Scheme_Object *o, Optimize_Info *info, int context)
@ -3743,7 +3758,7 @@ static Scheme_Object *optimize_wcm(Scheme_Object *o, Optimize_Info *info, int co
b = scheme_optimize_expr(wcm->body, info, scheme_optimize_tail_context(context));
if (omittable_key(k, info)
&& scheme_omittable_expr(b, -1, 20, 0, info, info, -1, 0))
&& scheme_omittable_expr(b, -1, 20, 0, info, info, 0, 0, ID_OMIT))
return make_discarding_first_sequence(v, b, info);
/* info->single_result is already set */
@ -4362,7 +4377,7 @@ int scheme_is_statically_proc(Scheme_Object *value, Optimize_Info *info)
Scheme_Let_Header *lh = (Scheme_Let_Header *)value;
if (lh->num_clauses == 1) {
Scheme_Compiled_Let_Value *lv = (Scheme_Compiled_Let_Value *)lh->body;
if (scheme_omittable_expr(lv->value, lv->count, 20, 0, info, NULL, -1, 0)) {
if (scheme_omittable_expr(lv->value, lv->count, 20, 0, info, NULL, 0, 0, ID_OMIT)) {
value = lv->body;
info = NULL;
} else
@ -4404,6 +4419,31 @@ static int is_values_apply(Scheme_Object *e, int n)
return 0;
}
static int can_reorder_values_arguments(Scheme_Object *e, Optimize_Info *info, int skip_depth)
{
/* We can reorder the argument as long at at most one is non-omitable,
treating mutable variables as non-omitable for this purpose */
if (SAME_TYPE(SCHEME_TYPE(e), scheme_application_type)) {
Scheme_App_Rec *app = (Scheme_App_Rec *)e;
int i, count = 0;
for (i = app->num_args; i--; ) {
if (scheme_omittable_expr(app->args[i+1], 1, 5, 0, info, info, skip_depth, 0, NO_MUTABLE_ID_OMIT))
count++;
}
return (count >= app->num_args - 1);
} else if (SAME_TYPE(SCHEME_TYPE(e), scheme_application2_type)) {
/* nothing to reorder */
return 1;
} else if (SAME_TYPE(SCHEME_TYPE(e), scheme_application3_type)) {
Scheme_App3_Rec *app = (Scheme_App3_Rec *)e;
return (scheme_omittable_expr(app->rand1, 1, 5, 0, info, info, skip_depth, 0, NO_MUTABLE_ID_OMIT)
|| scheme_omittable_expr(app->rand2, 1, 5, 0, info, info, skip_depth, 0, NO_MUTABLE_ID_OMIT));
}
return 0;
}
static int no_mutable_bindings(Scheme_Compiled_Let_Value *pre_body)
{
int i;
@ -4614,7 +4654,7 @@ scheme_optimize_lets(Scheme_Object *form, Optimize_Info *info, int for_inline, i
Scheme_Object *body, *value, *ready_pairs = NULL, *rp_last = NULL, *ready_pairs_start;
Scheme_Once_Used *first_once_used = NULL, *last_once_used = NULL, *once_used;
int i, j, pos, is_rec, not_simply_let_star = 0, undiscourage, split_shift, skip_opts = 0;
int did_set_value, checked_once;
int did_set_value, checked_once, skip_depth;
int remove_last_one = 0, inline_fuel, rev_bind_order;
int post_bind = !(SCHEME_LET_FLAGS(head) & (SCHEME_LET_RECURSIVE | SCHEME_LET_STAR));
@ -4922,14 +4962,20 @@ scheme_optimize_lets(Scheme_Object *form, Optimize_Info *info, int for_inline, i
/* Change (let-values ([(id ...) (values e ...)]) body)
to (let-values ([id e] ...) body) for simple e. */
skip_depth = (is_rec ? (pre_body->position + pre_body->count) : 0);
if ((pre_body->count != 1)
&& is_values_apply(value, pre_body->count)
&& ((!is_rec && no_mutable_bindings(pre_body))
|| scheme_omittable_expr(value, pre_body->count, -1, 0, info, info,
(is_rec
? (pre_body->position + pre_body->count)
: -1),
0))) {
&& ((!is_rec && no_mutable_bindings(pre_body)
&& (rev_bind_order
/* When !rev_bind_order, the transformation reorders the arguments
to `values`, so check that it's ok: */
|| can_reorder_values_arguments(value, rhs_info, skip_depth)))
/* If the right-hand side is omittable, then there are
no side effects, so reordering is always ok. We pass
NO_MUTABLE_ID_OMIT in case some other thread is mutating
an identifier in a way that could expose reordering: */
|| scheme_omittable_expr(value, pre_body->count, -1, 0, rhs_info, info,
skip_depth, 0, NO_MUTABLE_ID_OMIT))) {
if (!pre_body->count && !i) {
/* We want to drop the clause entirely, but doing it
here messes up the loop for letrec. So wait and
@ -5321,7 +5367,7 @@ scheme_optimize_lets(Scheme_Object *form, Optimize_Info *info, int for_inline, i
}
if (!used
&& (scheme_omittable_expr(pre_body->value, pre_body->count, -1, 0, info, info, -1, 0)
&& (scheme_omittable_expr(pre_body->value, pre_body->count, -1, 0, info, info, 0, 0, ID_OMIT)
|| ((pre_body->count == 1)
&& first_once_used
&& (first_once_used->pos == pos)
@ -5776,7 +5822,7 @@ static int is_general_compiled_proc(Scheme_Object *e, Optimize_Info *info)
if (seq->count > 0) {
int i;
for (i = seq->count - 1; i--; ) {
if (!scheme_omittable_expr(seq->array[i], -1, 20, 0, info, NULL, -1, 0))
if (!scheme_omittable_expr(seq->array[i], -1, 20, 0, info, NULL, 0, 0, ID_OMIT))
return 0;
}
}
@ -5833,7 +5879,7 @@ int split_define_values(Scheme_Object *e, int n, Scheme_Object *vars, Scheme_Obj
if (SAME_TYPE(SCHEME_TYPE(body), scheme_compiled_let_value_type)) {
Scheme_Compiled_Let_Value *lv = (Scheme_Compiled_Let_Value *)body;
if (lv->count == 1) {
if (!scheme_omittable_expr(lv->value, 1, 5, 0, NULL, NULL, n, 0))
if (!scheme_omittable_expr(lv->value, 1, 5, 0, NULL, NULL, n, 0, ID_OMIT))
return 0;
body = lv->body;
} else
@ -5882,8 +5928,8 @@ int split_define_values(Scheme_Object *e, int n, Scheme_Object *vars, Scheme_Obj
} else if ((n == 2) && SAME_TYPE(SCHEME_TYPE(e), scheme_application3_type)) {
Scheme_App3_Rec *app = (Scheme_App3_Rec *)e;
if (SAME_OBJ(app->rator, scheme_values_func)
&& scheme_omittable_expr(app->rand1, 1, 5, 0, NULL, NULL, 0, 0)
&& scheme_omittable_expr(app->rand2, 1, 5, 0, NULL, NULL, 0, 0)) {
&& scheme_omittable_expr(app->rand1, 1, 5, 0, NULL, NULL, 0, 0, ID_OMIT)
&& scheme_omittable_expr(app->rand2, 1, 5, 0, NULL, NULL, 0, 0, ID_OMIT)) {
if (vars) {
install_definition(vec, offset, SCHEME_CAR(vars), app->rand1);
vars = SCHEME_CDR(vars);
@ -5897,7 +5943,7 @@ int split_define_values(Scheme_Object *e, int n, Scheme_Object *vars, Scheme_Obj
if (SAME_OBJ(app->args[0], scheme_values_func)) {
int i;
for (i = 0; i < n; i++) {
if (!scheme_omittable_expr(app->args[i+1], 1, 5, 0, NULL, NULL, 0, 0))
if (!scheme_omittable_expr(app->args[i+1], 1, 5, 0, NULL, NULL, 0, 0, ID_OMIT))
return 0;
}
if (vars) {
@ -6074,7 +6120,7 @@ module_optimize(Scheme_Object *data, Optimize_Info *info, int context)
information that's only available at
optimization time: */
NULL,
info, -1, 0);
info, 0, 0, ID_OMIT);
if (n == 1) {
if (scheme_compiled_propagate_ok(e, info))
@ -6174,7 +6220,7 @@ module_optimize(Scheme_Object *data, Optimize_Info *info, int context)
}
}
} else {
cont = scheme_omittable_expr(e, -1, -1, 0, NULL, NULL, -1, 0);
cont = scheme_omittable_expr(e, -1, -1, 0, NULL, NULL, 0, 0, ID_OMIT);
}
if (i_m + 1 == cnt)
cont = 0;
@ -6348,7 +6394,7 @@ module_optimize(Scheme_Object *data, Optimize_Info *info, int context)
for (i_m = 0; i_m < cnt; i_m++) {
/* Optimize this expression: */
e = SCHEME_VEC_ELS(m->bodies[0])[i_m];
if (scheme_omittable_expr(e, -1, -1, 0, info, NULL, -1, 0)) {
if (scheme_omittable_expr(e, -1, -1, 0, info, NULL, 0, 0, ID_OMIT)) {
can_omit++;
}
}
@ -6359,7 +6405,7 @@ module_optimize(Scheme_Object *data, Optimize_Info *info, int context)
for (i_m = 0; i_m < cnt; i_m++) {
/* Optimize this expression: */
e = SCHEME_VEC_ELS(m->bodies[0])[i_m];
if (!scheme_omittable_expr(e, -1, -1, 0, info, NULL, -1, 0)) {
if (!scheme_omittable_expr(e, -1, -1, 0, info, NULL, 0, 0, ID_OMIT)) {
SCHEME_VEC_ELS(vec)[j++] = e;
}
}

4
racket/src/racket/src/resolve.c
View File

@ -512,7 +512,7 @@ static Scheme_Object *look_for_letv_change(Scheme_Sequence *s)
v = s->array[i];
if (SAME_TYPE(SCHEME_TYPE(v), scheme_let_value_type)) {
Scheme_Let_Value *lv = (Scheme_Let_Value *)v;
if (scheme_omittable_expr(lv->body, 1, -1, 0, NULL, NULL, -1, 0)) {
if (scheme_omittable_expr(lv->body, 1, -1, 0, NULL, NULL, 0, 0, 0)) {
int esize = s->count - (i + 1);
int nsize = i + 1;
Scheme_Object *nv, *ev;
@ -1248,7 +1248,7 @@ scheme_resolve_lets(Scheme_Object *form, Resolve_Info *info)
}
if (j >= 0)
break;
if (!scheme_omittable_expr(clv->value, clv->count, -1, 0, NULL, NULL, -1, 0))
if (!scheme_omittable_expr(clv->value, clv->count, -1, 0, NULL, NULL, 0, 0, 0))
break;
}
if (i < 0) {

3
racket/src/racket/src/schpriv.h
View File

@ -3094,7 +3094,8 @@ int scheme_used_app_only(Scheme_Comp_Env *env, int which);
int scheme_used_ever(Scheme_Comp_Env *env, int which);
int scheme_omittable_expr(Scheme_Object *o, int vals, int fuel, int resolved,
Optimize_Info *opt_info, Optimize_Info *warn_info, int deeper_than, int no_id);
Optimize_Info *opt_info, Optimize_Info *warn_info,
int min_id_depth, int id_offset, int no_id);
int scheme_might_invoke_call_cc(Scheme_Object *value);
int scheme_is_liftable(Scheme_Object *o, int bind_count, int fuel, int as_rator, int or_escape);
int scheme_is_functional_nonfailing_primitive(Scheme_Object *rator, int num_args, int expected_vals);

2
racket/src/racket/src/sfs.c
View File

@ -689,7 +689,7 @@ static Scheme_Object *sfs_let_one(Scheme_Object *o, SFS_Info *info)
it might not because (1) it was introduced late by inlining,
or (2) the rhs expression doesn't always produce a single
value. */
if (scheme_omittable_expr(rhs, 1, -1, 1, NULL, NULL, -1, 0)) {
if (scheme_omittable_expr(rhs, 1, -1, 1, NULL, NULL, 0, 0, 0)) {
rhs = scheme_false;
} else if ((ip < info->max_calls[pos])
&& SAME_TYPE(SCHEME_TYPE(rhs), scheme_toplevel_type)) {