On Thu, Nov 15, 2012 at 04:13:01PM +0000, Nicholas Clark wrote:
> Following a chat on IRC today:
>
> 09:28 < nwc10> I see accesses to all structure members except constraints in
> the rest of the code
> 09:29 < jnthn> Yeah. It could be moved into Rakudo_md_candidate_graph_node if
> it's only used in the sort.
> 09:30 < nwc10> aha. good plan. I'd not thought of doing it like that.
>
> http://irclog.perlgeek.de/perl6/2012-11-15#i_6155821
>
>
> Is this attached patch the way to go?
After chat on IRC, this is an improved version. I forgot to send it anywhere
Specifically, we both think that using lots of parameters is ugly.
Improved version passes in a Rakudo_md_candidate_graph_node instead of using
Rakudo_md_candidate_info
> -=item C<static INTVAL is_narrower(PARROT_INTERP, Rakudo_md_candidate_info
> *a, Rakudo_md_candidate_info *b)>
> +=item C<static INTVAL is_narrower(PARROT_INTERP, Rakudo_md_candidate_info
> *a, PMC **a_constraints, Rakudo_md_candidate_info *b, PMC **b_constraints)>
Nicholas Clark
>From 77bd81d5a2ef1c1d27ddc418469e4a60d88e7a86 Mon Sep 17 00:00:00 2001
From: Nicholas Clark <n...@ccl4.org>
Date: Thu, 15 Nov 2012 16:52:33 +0100
Subject: [PATCH] Move constraints from Rakudo_md_candidate_info to
Rakudo_md_candidate_graph_node as it's only needed while generating the
sorted candidate list.
---
src/binder/multidispatch.c | 46 ++++++++++++++++++++++++++--------------------
src/binder/multidispatch.h | 3 ++-
2 files changed, 28 insertions(+), 21 deletions(-)
diff --git a/src/binder/multidispatch.c b/src/binder/multidispatch.c
index 31bba2f..baec088 100644
--- a/src/binder/multidispatch.c
+++ b/src/binder/multidispatch.c
@@ -40,7 +40,7 @@ This implements Perl 6 multiple dispatch.
=over 4
-=item C<static INTVAL is_narrower(PARROT_INTERP, Rakudo_md_candidate_info *a, Rakudo_md_candidate_info *b)>
+=item C<static INTVAL is_narrower(PARROT_INTERP, Rakudo_md_candidate_graph_node *a, Rakudo_md_candidate_graph_node *b)>
Takes two candidates and determines if the first one is narrower than the
second. Returns a true value if they are.
@@ -48,26 +48,30 @@ second. Returns a true value if they are.
=cut
*/
-static INTVAL is_narrower(PARROT_INTERP, Rakudo_md_candidate_info *a, Rakudo_md_candidate_info *b) {
+static INTVAL is_narrower(PARROT_INTERP,
+ Rakudo_md_candidate_graph_node *a,
+ Rakudo_md_candidate_graph_node *b) {
INTVAL narrower = 0;
INTVAL tied = 0;
INTVAL i, types_to_check;
+ Rakudo_md_candidate_info *const a_info = a->info;
+ Rakudo_md_candidate_info *const b_info = b->info;
/* Work out how many parameters to compare, factoring in slurpiness
* and optionals. */
- if (a->num_types == b->num_types)
- types_to_check = a->num_types;
- else if (a->min_arity == b->min_arity)
- types_to_check = a->num_types > b->num_types ? b->num_types : a->num_types;
- else if (a->max_arity != SLURPY_ARITY && b->max_arity == SLURPY_ARITY)
+ if (a_info->num_types == b_info->num_types)
+ types_to_check = a_info->num_types;
+ else if (a_info->min_arity == b_info->min_arity)
+ types_to_check = a_info->num_types > b_info->num_types ? b_info->num_types : a_info->num_types;
+ else if (a_info->max_arity != SLURPY_ARITY && b_info->max_arity == SLURPY_ARITY)
return 1;
else
return 0;
/* Analyse each parameter in the two candidates. */
for (i = 0; i < types_to_check; i++) {
- PMC * const type_obj_a = a->types[i];
- PMC * const type_obj_b = b->types[i];
+ PMC * const type_obj_a = a_info->types[i];
+ PMC * const type_obj_b = b_info->types[i];
if (type_obj_a == type_obj_b) {
/* Same type; narrower if first has constraints and other doesn't;
* tied if neither has constraints or both have constraints. */
@@ -78,12 +82,12 @@ static INTVAL is_narrower(PARROT_INTERP, Rakudo_md_candidate_info *a, Rakudo_md_
(!PMC_IS_NULL(a->constraints[i]) && !PMC_IS_NULL(b->constraints[i])))
tied++;
}
- else if ((a->type_flags[i] & TYPE_NATIVE_MASK) && !(b->type_flags[i] & TYPE_NATIVE_MASK))
+ else if ((a_info->type_flags[i] & TYPE_NATIVE_MASK) && !(b_info->type_flags[i] & TYPE_NATIVE_MASK))
{
/* Narrower because natives always are. */
narrower++;
}
- else if ((b->type_flags[i] & TYPE_NATIVE_MASK) && !(a->type_flags[i] & TYPE_NATIVE_MASK))
+ else if ((b_info->type_flags[i] & TYPE_NATIVE_MASK) && !(a_info->type_flags[i] & TYPE_NATIVE_MASK))
{
/* Wider; skip over here so we don't go counting this as tied in
* the next branch. */
@@ -112,15 +116,15 @@ static INTVAL is_narrower(PARROT_INTERP, Rakudo_md_candidate_info *a, Rakudo_md_
/* Otherwise, we see if one has a slurpy and the other not. A lack of
* slurpiness makes the candidate narrower. */
- if (a->max_arity != SLURPY_ARITY && b->max_arity == SLURPY_ARITY) {
+ if (a_info->max_arity != SLURPY_ARITY && b_info->max_arity == SLURPY_ARITY) {
return 1;
}
/* Also narrower if the first needs a bind check and the second doesn't, if
* we wouldn't deem the other one narrower than this one int terms of
* slurpyness. Otherwise, they're tied. */
- return !(b->max_arity != SLURPY_ARITY && a->max_arity == SLURPY_ARITY)
- && (a->bind_check && !(b->bind_check));
+ return !(b_info->max_arity != SLURPY_ARITY && a_info->max_arity == SLURPY_ARITY)
+ && (a_info->bind_check && !(b_info->bind_check));
}
@@ -158,6 +162,7 @@ static Rakudo_md_candidate_info** sort_candidates(PARROT_INTERP, PMC *candidates
INTVAL num_params;
INTVAL j;
INTVAL significant_param;
+ PMC **constraints;
/* Get information about this candidate. */
PMC * const candidate = VTABLE_get_pmc_keyed_int(interp, candidates, i);
@@ -174,7 +179,7 @@ static Rakudo_md_candidate_info** sort_candidates(PARROT_INTERP, PMC *candidates
/* Type information. */
info->types = mem_allocate_n_zeroed_typed(num_params + 1, PMC*);
info->type_flags = mem_allocate_n_zeroed_typed(num_params + 1, INTVAL);
- info->constraints = mem_allocate_n_zeroed_typed(num_params + 1, PMC*);
+ constraints = mem_allocate_n_zeroed_typed(num_params + 1, PMC*);
significant_param = 0;
for (j = 0; j < num_params; j++) {
@@ -220,8 +225,8 @@ static Rakudo_md_candidate_info** sort_candidates(PARROT_INTERP, PMC *candidates
else {
info->types[significant_param] = param->nominal_type;
}
- info->constraints[significant_param] = param->post_constraints;
- if (!PMC_IS_NULL(info->constraints[significant_param]))
+ constraints[significant_param] = param->post_constraints;
+ if (!PMC_IS_NULL(constraints[significant_param]))
info->bind_check = 1;
if (param->flags & SIG_ELEM_MULTI_INVOCANT)
info->num_types++;
@@ -241,6 +246,7 @@ static Rakudo_md_candidate_info** sort_candidates(PARROT_INTERP, PMC *candidates
/* Add it to graph node, and initialize list of edges. */
graph[insert_pos] = mem_allocate_zeroed_typed(Rakudo_md_candidate_graph_node);
graph[insert_pos]->info = info;
+ graph[insert_pos]->constraints = constraints;
graph[insert_pos]->edges = mem_allocate_n_zeroed_typed(
num_candidates, Rakudo_md_candidate_graph_node*);
@@ -262,7 +268,7 @@ static Rakudo_md_candidate_info** sort_candidates(PARROT_INTERP, PMC *candidates
for (j = 0; j < num_candidates; j++) {
if (i == j)
continue;
- if (is_narrower(interp, graph[i]->info, graph[j]->info)) {
+ if (is_narrower(interp, graph[i], graph[j])) {
graph[i]->edges[graph[i]->edges_out] = graph[j];
graph[i]->edges_out++;
graph[j]->edges_in++;
@@ -318,10 +324,10 @@ static Rakudo_md_candidate_info** sort_candidates(PARROT_INTERP, PMC *candidates
mem_sys_free(info->types);
if (info->type_flags)
mem_sys_free(info->type_flags);
- if (info->constraints)
- mem_sys_free(info->constraints);
mem_sys_free(info);
}
+ if (graph[i]->constraints)
+ mem_sys_free(graph[i]->constraints);
mem_sys_free(graph[i]->edges);
mem_sys_free(graph[i]);
}
diff --git a/src/binder/multidispatch.h b/src/binder/multidispatch.h
index 3338f53..e9f6552 100644
--- a/src/binder/multidispatch.h
+++ b/src/binder/multidispatch.h
@@ -37,7 +37,6 @@ typedef struct {
PMC *signature; /* The signature of the sub. */
PMC **types; /* Class or role type constraints for each parameter. */
INTVAL *type_flags; /* Definedness and native flags for each of the types. */
- PMC **constraints; /* Refinement type constraints for each parameter. */
INTVAL num_types; /* Number of entries in the above two arrays. */
INTVAL min_arity; /* Number of required positional arguments. */
INTVAL max_arity; /* Number of required and optional positional arguments. */
@@ -86,6 +85,8 @@ typedef struct {
* in the graph that we have arrows to. */
typedef struct candidate_graph_node {
Rakudo_md_candidate_info *info;
+ /* Refinement type constraints for each parameter, only used in the sort. */
+ PMC **constraints;
struct candidate_graph_node **edges;
INTVAL edges_in;
INTVAL edges_out;
--
1.8.0.1
