commit 64bf2c270ed8bb417615c1e15f84f44585f815e4
parent e7966eafde08d5c6f71695a47f87f23ca740a8f8
Author: William Casarin <jb55@jb55.com>
Date: Fri, 16 Jul 2021 17:48:06 -0700
use function locals like they were intended
get rid of the weird local stack we were using
Signed-off-by: William Casarin <jb55@jb55.com>
Diffstat:
| M | src/wasm.c | | | 141 | ++++++++++++++++++++++++++++++++++--------------------------------------------- |
| M | src/wasm.h | | | 17 | +++++++++++++---- |
2 files changed, 73 insertions(+), 85 deletions(-)
diff --git a/src/wasm.c b/src/wasm.c
@@ -25,16 +25,6 @@
static const int MAX_LABELS = 128;
-struct val {
- enum valtype type;
- union {
- int i32;
- u64 i64;
- float f32;
- double f64;
- };
-};
-
struct expr_parser {
struct wasm_interp *interp; // optional...
struct cursor *code;
@@ -82,18 +72,61 @@ static INLINE int offset_stack_top(struct cursor *cur)
return *(p - sizeof(*p));
}
-static INLINE struct val *get_local(struct wasm_interp *interp, int ind)
+static INLINE struct local *get_locals(struct func *func, int *num_locals)
+{
+ switch (func->type) {
+ case func_type_wasm:
+ *num_locals = func->wasm_func->num_locals;
+ return func->wasm_func->locals;
+ case func_type_builtin:
+ *num_locals = func->builtin->num_locals;
+ return func->builtin->locals;
+ }
+ return NULL;
+}
+
+static INLINE int is_valid_fn_index(struct module *module, int ind)
+{
+ return ind >= 0 && ind < module->num_funcs;
+}
+
+static INLINE struct func *get_function(struct module *module, int ind)
+{
+ if (unlikely(!is_valid_fn_index(module, ind)))
+ return NULL;
+ return &module->funcs[ind];
+}
+
+static struct val *get_local(struct wasm_interp *interp, int ind)
{
- struct val *p;
- int offset = offset_stack_top(&interp->locals_offsets);
+ struct callframe *frame;
+ struct func *func;
+ struct local *locals;
+ int num_locals;
+
+ if (unlikely(!(frame = top_callframe(&interp->callframes)))) {
+ interp_error(interp, "no callframe?");
+ return NULL;
+ }
+
+ if (unlikely(!(func = get_function(interp->module, frame->fn)))) {
+ interp_error(interp, "unknown fn %d", frame->fn);
+ return NULL;
+ }
- if (unlikely(!(p = index_cursor(&interp->locals, offset + ind,
- sizeof(struct val))))) {
- interp_error(interp, "%d local oob %d > %ld", ind, offset + ind,
- interp->locals.end - interp->locals.start);
+ if (unlikely(!(locals = get_locals(func, &num_locals)))) {
+ interp_error(interp, "couldn't find locals for %s",
+ func->name);
return NULL;
}
- return p;
+
+ if (unlikely(!(ind >= num_locals))) {
+ interp_error(interp, "local index %d too high for %s (max %d)",
+ ind, func->name, num_locals-1);
+ return NULL;
+ }
+
+ return &locals[ind].val;
}
static INLINE int stack_pop_i32(struct wasm_interp *interp, int *i)
@@ -560,18 +593,6 @@ static INLINE int count_imported_functions(struct module *module)
return count_imports(module, &typ);
}
-static INLINE int is_valid_fn_index(struct module *module, int ind)
-{
- return ind >= 0 && ind < module->num_funcs;
-}
-
-static INLINE struct func *get_function(struct module *module, int ind)
-{
- if (unlikely(!is_valid_fn_index(module, ind)))
- return NULL;
- return &module->funcs[ind];
-}
-
static INLINE const char *get_function_name(struct module *module, int fn)
{
struct func *func = NULL;
@@ -932,12 +953,12 @@ static int parse_export(struct wasm_parser *p, struct wexport *export)
static int parse_local(struct wasm_parser *p, struct local *local)
{
- if (unlikely(!leb128_read(&p->cur, &local->n))) {
+ if (unlikely(!leb128_read(&p->cur, (unsigned int*)&local->val.i32))) {
parse_err(p, "n");
return 0;
}
- if (unlikely(!parse_valtype(p, &local->valtype))) {
+ if (unlikely(!parse_valtype(p, &local->val.type))) {
parse_err(p, "valtype");
return 0;
}
@@ -2074,37 +2095,15 @@ static int interp_i32_sub(struct wasm_interp *interp)
return cursor_pushval(&interp->stack, &c);
}
-static INLINE int count_locals(struct wasm_interp *interp)
-{
- int offset = offset_stack_top(&interp->locals_offsets);
- int count = cursor_count(&interp->locals, sizeof(struct val));
- return count - offset;
-}
-
static int set_local(struct wasm_interp *interp, int ind, struct val *val)
{
struct val *local;
- int nlocals;
-
- nlocals = count_locals(interp);
- if (ind > nlocals) {
- /* TODO: if we hit this then we need to push empty locals up to the index */
- interp_error(interp, "local index out of order");
- return 0;
+ if (unlikely(!(local = get_local(interp, ind)))) {
+ return interp_error(interp, "no local?");
}
- if (ind < nlocals) {
- debug("memsetting local %d\n", ind);
- if (!(local = get_local(interp, ind))) {
- return 0;
- }
- memcpy(local, val, sizeof(*val));
- return 1;
- }
-
- cursor_pushval(&interp->locals, val);
- assert(count_locals(interp) > 0);
+ memcpy(local, val, sizeof(*val));
return 1;
}
@@ -2136,7 +2135,6 @@ static int interp_local_set(struct wasm_interp *interp)
static int interp_local_get(struct wasm_interp *interp)
{
unsigned int index;
- unsigned int nlocals;
struct val *val;
struct cursor *code;
@@ -2150,13 +2148,6 @@ static int interp_local_get(struct wasm_interp *interp)
return 0;
}
- nlocals = count_locals(interp);
- if (unlikely(index >= nlocals)) {
- interp_error(interp, "local %d not set (%d locals)", index,
- nlocals);
- return 0;
- }
-
if (unlikely(!(val = get_local(interp, index)))) {
interp_error(interp, "get local");
return 0;
@@ -2295,13 +2286,9 @@ static int prepare_call(struct wasm_interp *interp, int func_index)
interp->module->code_section.num_funcs);
}
- /* record locals offset for indexing locals in the next function */
- offset = cursor_count(&interp->locals, sizeof(struct val));
- if (unlikely(!cursor_push_int(&interp->locals_offsets, offset)))
- return interp_error(interp, "push locals offset");
-
offset = count_resolvers(interp);
- /* this is like locals offsets but for label resolvers */
+ /* push label resolver offsets, used to keep track of per-func resolvers */
+ /* TODO: maybe move this data to struct func? */
if (unlikely(!cursor_push_int(&interp->resolver_offsets, offset)))
return interp_error(interp, "push resolver offset");
@@ -2343,8 +2330,8 @@ static int prepare_call(struct wasm_interp *interp, int func_index)
valtype_name(paramtype));
}
- if (unlikely(!cursor_pushval(&interp->locals, &val))) {
- return interp_error(interp, "push param local");
+ if (unlikely(!set_local(interp, i, &val))) {
+ return interp_error(interp, "set param local %d", i);
}
}
@@ -3089,10 +3076,6 @@ int interp_code(struct wasm_interp *interp)
return interp_error(interp,
"pop resolver_offsets");
}
- if (!cursor_popint(&interp->locals_offsets,
- &offset))
- return interp_error(interp,
- "pop locals_offset");
break;
}
}
@@ -3206,8 +3189,6 @@ void wasm_interp_init(struct wasm_interp *interp, struct module *module)
ok =
cursor_slice(&interp->mem, &interp->stack, stack_size) &&
cursor_slice(&interp->mem, &interp->errors.cur, errors_size) &&
- cursor_slice(&interp->mem, &interp->locals, locals_size) &&
- cursor_slice(&interp->mem, &interp->locals_offsets, offsets_size) &&
cursor_slice(&interp->mem, &interp->resolver_offsets, resolver_offsets_size) &&
cursor_slice(&interp->mem, &interp->callframes, callframes_size) &&
cursor_slice(&interp->mem, &interp->resolver_stack, resolver_size) &&
@@ -3243,8 +3224,6 @@ int interp_wasm_module(struct wasm_interp *interp)
reset_cursor(&interp->resolver_stack);
reset_cursor(&interp->resolver_offsets);
reset_cursor(&interp->errors.cur);
- reset_cursor(&interp->locals);
- reset_cursor(&interp->locals_offsets);
reset_cursor(&interp->callframes);
// don't reset labels for perf!
diff --git a/src/wasm.h b/src/wasm.h
@@ -181,9 +181,18 @@ struct global {
struct expr init;
};
+struct val {
+ enum valtype type;
+ union {
+ int i32;
+ u64 i64;
+ float f32;
+ double f64;
+ };
+};
+
struct local {
- unsigned int n;
- enum valtype valtype;
+ struct val val;
};
/* "code" */
@@ -486,8 +495,6 @@ struct wasm_interp {
struct cursor callframes; /* struct callframe */
struct cursor stack; /* struct val */
struct cursor mem; /* u8/mixed */
- struct cursor locals; /* struct val */
- struct cursor locals_offsets; /* int */
struct cursor resolver_offsets; /* int */
struct array labels; /* struct labels */
@@ -501,6 +508,8 @@ struct wasm_interp {
struct builtin {
const char *name;
+ struct local locals[8];
+ int num_locals;
int (*fn)(struct wasm_interp *);
int (*prepare_args)(struct wasm_interp *);
};
