Initial commit.
diff --git a/py/parse.c b/py/parse.c
new file mode 100644
index 0000000..94a5a5d
--- /dev/null
+++ b/py/parse.c
@@ -0,0 +1,565 @@
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+#include <assert.h>
+
+#include "misc.h"
+#include "lexer.h"
+#include "machine.h"
+#include "parse.h"
+
+#define RULE_ACT_KIND_MASK (0xf0)
+#define RULE_ACT_ARG_MASK (0x0f)
+#define RULE_ACT_OR (0x10)
+#define RULE_ACT_AND (0x20)
+#define RULE_ACT_LIST (0x30)
+
+#define RULE_ARG_BLANK (0x0000)
+#define RULE_ARG_KIND_MASK (0xf000)
+#define RULE_ARG_ARG_MASK (0x0fff)
+#define RULE_ARG_TOK (0x1000)
+#define RULE_ARG_RULE (0x2000)
+#define RULE_ARG_OPT_TOK (0x3000)
+#define RULE_ARG_OPT_RULE (0x4000)
+
+// (un)comment to use rule names; for debugging
+//#define USE_RULE_NAME (1)
+
+typedef struct _rule_t {
+ byte rule_id;
+ byte act;
+#ifdef USE_RULE_NAME
+ const char *rule_name;
+#endif
+ uint16_t arg[];
+} rule_t;
+
+enum {
+ RULE_none = 0,
+#define DEF_RULE(rule, comp, kind, arg...) RULE_##rule,
+#include "grammar.h"
+#undef DEF_RULE
+ RULE_maximum_number_of,
+};
+
+#define or(n) (RULE_ACT_OR | n)
+#define and(n) (RULE_ACT_AND | n)
+#define one_or_more (RULE_ACT_LIST | 2)
+#define list (RULE_ACT_LIST | 1)
+#define list_with_end (RULE_ACT_LIST | 3)
+#define tok(t) (RULE_ARG_TOK | PY_TOKEN_##t)
+#define rule(r) (RULE_ARG_RULE | RULE_##r)
+#define opt_tok(t) (RULE_ARG_OPT_TOK | PY_TOKEN_##t)
+#define opt_rule(r) (RULE_ARG_OPT_RULE | RULE_##r)
+#ifdef USE_RULE_NAME
+#define DEF_RULE(rule, comp, kind, arg...) static rule_t rule_##rule = { RULE_##rule, kind, #rule, { arg } };
+#else
+#define DEF_RULE(rule, comp, kind, arg...) static rule_t rule_##rule = { RULE_##rule, kind, { arg } };
+#endif
+#include "grammar.h"
+#undef or
+#undef and
+#undef list
+#undef list_with_end
+#undef tok
+#undef rule
+#undef opt_tok
+#undef opt_rule
+#undef one_or_more
+#undef DEF_RULE
+
+static rule_t *rules[] = {
+ NULL,
+#define DEF_RULE(rule, comp, kind, arg...) &rule_##rule,
+#include "grammar.h"
+#undef DEF_RULE
+};
+
+typedef struct _rule_stack_t {
+ byte rule_id;
+ int32_t arg_i; // what should be the size and signedness?
+} rule_stack_t;
+
+typedef struct _parser_t {
+ uint rule_stack_alloc;
+ uint rule_stack_top;
+ rule_stack_t *rule_stack;
+
+ uint result_stack_top;
+ py_parse_node_t *result_stack;
+} parser_t;
+
+static void push_rule(parser_t *parser, rule_t *rule, int arg_i) {
+ if (parser->rule_stack_top >= parser->rule_stack_alloc) {
+ parser->rule_stack_alloc *= 2;
+ parser->rule_stack = m_renew(rule_stack_t, parser->rule_stack, parser->rule_stack_alloc);
+ }
+ parser->rule_stack[parser->rule_stack_top].rule_id = rule->rule_id;
+ parser->rule_stack[parser->rule_stack_top].arg_i = arg_i;
+ parser->rule_stack_top += 1;
+}
+
+static void push_rule_from_arg(parser_t *parser, uint arg) {
+ assert((arg & RULE_ARG_KIND_MASK) == RULE_ARG_RULE || (arg & RULE_ARG_KIND_MASK) == RULE_ARG_OPT_RULE);
+ uint rule_id = arg & RULE_ARG_ARG_MASK;
+ assert(rule_id < RULE_maximum_number_of);
+ push_rule(parser, rules[rule_id], 0);
+}
+
+static void pop_rule(parser_t *parser, rule_t **rule, uint *arg_i) {
+ parser->rule_stack_top -= 1;
+ *rule = rules[parser->rule_stack[parser->rule_stack_top].rule_id];
+ *arg_i = parser->rule_stack[parser->rule_stack_top].arg_i;
+}
+
+py_parse_node_t py_parse_node_new_leaf(machine_int_t kind, machine_int_t arg) {
+ return (py_parse_node_t)(kind | (arg << 4));
+}
+
+int num_parse_nodes_allocated = 0;
+py_parse_node_struct_t *parse_node_new_struct(int rule_id, int num_args) {
+ py_parse_node_struct_t *pn = m_malloc(sizeof(py_parse_node_struct_t) + num_args * sizeof(py_parse_node_t));
+ pn->source = 0; // TODO
+ pn->kind_num_nodes = (rule_id & 0xff) | (num_args << 8);
+ num_parse_nodes_allocated += 1;
+ return pn;
+}
+
+void parse_node_show(py_parse_node_t pn, int indent) {
+ for (int i = 0; i < indent; i++) {
+ printf(" ");
+ }
+ if (PY_PARSE_NODE_IS_NULL(pn)) {
+ printf("NULL\n");
+ } else if (PY_PARSE_NODE_IS_LEAF(pn)) {
+ int arg = PY_PARSE_NODE_LEAF_ARG(pn);
+ switch (PY_PARSE_NODE_LEAF_KIND(pn)) {
+ case PY_PARSE_NODE_ID: printf("id(%s)\n", qstr_str(arg)); break;
+ case PY_PARSE_NODE_SMALL_INT: printf("int(%d)\n", arg); break;
+ case PY_PARSE_NODE_INTEGER: printf("int(%s)\n", qstr_str(arg)); break;
+ case PY_PARSE_NODE_DECIMAL: printf("dec(%s)\n", qstr_str(arg)); break;
+ case PY_PARSE_NODE_STRING: printf("str(%s)\n", qstr_str(arg)); break;
+ case PY_PARSE_NODE_BYTES: printf("bytes(%s)\n", qstr_str(arg)); break;
+ case PY_PARSE_NODE_TOKEN: printf("tok(%d)\n", arg); break;
+ default: assert(0);
+ }
+ } else {
+ py_parse_node_struct_t *pns2 = (py_parse_node_struct_t*)pn;
+ int n = pns2->kind_num_nodes >> 8;
+#ifdef USE_RULE_NAME
+ printf("%s(%d) (n=%d)\n", rules[PY_PARSE_NODE_STRUCT_KIND(pns2)]->rule_name, PY_PARSE_NODE_STRUCT_KIND(pns2), n);
+#else
+ printf("rule(%u) (n=%d)\n", (uint)PY_PARSE_NODE_STRUCT_KIND(pns2), n);
+#endif
+ for (int i = 0; i < n; i++) {
+ parse_node_show(pns2->nodes[i], indent + 2);
+ }
+ }
+}
+
+/*
+static void result_stack_show(parser_t *parser) {
+ printf("result stack, most recent first\n");
+ for (int i = parser->result_stack_top - 1; i >= 0; i--) {
+ parse_node_show(parser->result_stack[i], 0);
+ }
+}
+*/
+
+static py_parse_node_t pop_result(parser_t *parser) {
+ assert(parser->result_stack_top > 0);
+ return parser->result_stack[--parser->result_stack_top];
+}
+
+static py_parse_node_t peek_result(parser_t *parser, int pos) {
+ assert(parser->result_stack_top > pos);
+ return parser->result_stack[parser->result_stack_top - 1 - pos];
+}
+
+static void push_result_node(parser_t *parser, py_parse_node_t pn) {
+ parser->result_stack[parser->result_stack_top++] = pn;
+}
+
+static void push_result_token(parser_t *parser, const py_lexer_t *lex) {
+ const py_token_t *tok = py_lexer_cur(lex);
+ py_parse_node_t pn;
+ if (tok->kind == PY_TOKEN_NAME) {
+ pn = py_parse_node_new_leaf(PY_PARSE_NODE_ID, qstr_from_strn_copy(tok->str, tok->len));
+ } else if (tok->kind == PY_TOKEN_NUMBER) {
+ bool dec = false;
+ bool small_int = true;
+ int int_val = 0;
+ int len = tok->len;
+ const char *str = tok->str;
+ int base = 10;
+ int i = 0;
+ if (len >= 3 && str[0] == '0') {
+ if (str[1] == 'o' || str[1] == 'O') {
+ // octal
+ base = 8;
+ i = 2;
+ } else if (str[1] == 'x' || str[1] == 'X') {
+ // hexadecimal
+ base = 16;
+ i = 2;
+ } else if (str[1] == 'b' || str[1] == 'B') {
+ // binary
+ base = 2;
+ i = 2;
+ }
+ }
+ for (; i < len; i++) {
+ if (g_unichar_isdigit(str[i]) && str[i] - '0' < base) {
+ int_val = base * int_val + str[i] - '0';
+ } else if (base == 16 && 'a' <= str[i] && str[i] <= 'f') {
+ int_val = base * int_val + str[i] - 'a' + 10;
+ } else if (base == 16 && 'F' <= str[i] && str[i] <= 'F') {
+ int_val = base * int_val + str[i] - 'A' + 10;
+ } else if (str[i] == '.' || str[i] == 'e' || str[i] == 'E') {
+ dec = true;
+ break;
+ } else {
+ small_int = false;
+ break;
+ }
+ }
+ if (dec) {
+ pn = py_parse_node_new_leaf(PY_PARSE_NODE_DECIMAL, qstr_from_strn_copy(str, len));
+ } else if (small_int && -0x10000 <= int_val && int_val <= 0xffff) {
+ pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, int_val);
+ } else {
+ pn = py_parse_node_new_leaf(PY_PARSE_NODE_INTEGER, qstr_from_strn_copy(str, len));
+ }
+ } else if (tok->kind == PY_TOKEN_STRING) {
+ pn = py_parse_node_new_leaf(PY_PARSE_NODE_STRING, qstr_from_strn_copy(tok->str, tok->len));
+ } else if (tok->kind == PY_TOKEN_BYTES) {
+ pn = py_parse_node_new_leaf(PY_PARSE_NODE_BYTES, qstr_from_strn_copy(tok->str, tok->len));
+ } else {
+ pn = py_parse_node_new_leaf(PY_PARSE_NODE_TOKEN, tok->kind);
+ }
+ push_result_node(parser, pn);
+}
+
+static void push_result_rule(parser_t *parser, rule_t *rule, int num_args) {
+ py_parse_node_struct_t *pn = parse_node_new_struct(rule->rule_id, num_args);
+ for (int i = num_args; i > 0; i--) {
+ pn->nodes[i - 1] = pop_result(parser);
+ }
+ push_result_node(parser, (py_parse_node_t)pn);
+}
+
+py_parse_node_t py_parse(py_lexer_t *lex, int wanted_rule) {
+ wanted_rule = RULE_file_input;
+ parser_t *parser = m_new(parser_t, 1);
+ parser->rule_stack_alloc = 64;
+ parser->rule_stack_top = 0;
+ parser->rule_stack = m_new(rule_stack_t, parser->rule_stack_alloc);
+
+ parser->result_stack = m_new(py_parse_node_t, 1000);
+ parser->result_stack_top = 0;
+
+ push_rule(parser, rules[wanted_rule], 0);
+
+ uint n, i;
+ bool backtrack = false;
+ rule_t *rule;
+ py_token_kind_t tok_kind;
+ bool emit_rule;
+ bool had_trailing_sep;
+
+ for (;;) {
+ next_rule:
+ if (parser->rule_stack_top == 0) {
+ break;
+ }
+
+ pop_rule(parser, &rule, &i);
+ n = rule->act & RULE_ACT_ARG_MASK;
+
+ /*
+ // debugging
+ printf("depth=%d ", parser->rule_stack_top);
+ for (int j = 0; j < parser->rule_stack_top; ++j) {
+ printf(" ");
+ }
+ printf("%s n=%d i=%d bt=%d\n", rule->rule_name, n, i, backtrack);
+ */
+
+ switch (rule->act & RULE_ACT_KIND_MASK) {
+ case RULE_ACT_OR:
+ if (i > 0 && !backtrack) {
+ goto next_rule;
+ } else {
+ backtrack = false;
+ }
+ for (; i < n - 1; ++i) {
+ switch (rule->arg[i] & RULE_ARG_KIND_MASK) {
+ case RULE_ARG_TOK:
+ if (py_lexer_is_kind(lex, rule->arg[i] & RULE_ARG_ARG_MASK)) {
+ push_result_token(parser, lex);
+ py_lexer_to_next(lex);
+ goto next_rule;
+ }
+ break;
+ case RULE_ARG_RULE:
+ push_rule(parser, rule, i + 1);
+ push_rule_from_arg(parser, rule->arg[i]);
+ goto next_rule;
+ default:
+ assert(0);
+ }
+ }
+ if ((rule->arg[i] & RULE_ARG_KIND_MASK) == RULE_ARG_TOK) {
+ if (py_lexer_is_kind(lex, rule->arg[i] & RULE_ARG_ARG_MASK)) {
+ push_result_token(parser, lex);
+ py_lexer_to_next(lex);
+ } else {
+ backtrack = true;
+ goto next_rule;
+ }
+ } else {
+ push_rule_from_arg(parser, rule->arg[i]);
+ }
+ break;
+
+ case RULE_ACT_AND:
+
+ // failed, backtrack if we can, else syntax error
+ if (backtrack) {
+ assert(i > 0);
+ if ((rule->arg[i - 1] & RULE_ARG_KIND_MASK) == RULE_ARG_OPT_RULE) {
+ // an optional rule that failed, so continue with next arg
+ push_result_node(parser, PY_PARSE_NODE_NULL);
+ backtrack = false;
+ } else {
+ // a mandatory rule that failed, so propagate backtrack
+ if (i > 1) {
+ // already eaten tokens so can't backtrack
+ goto syntax_error;
+ } else {
+ goto next_rule;
+ }
+ }
+ }
+
+ // progress through the rule
+ for (; i < n; ++i) {
+ switch (rule->arg[i] & RULE_ARG_KIND_MASK) {
+ case RULE_ARG_TOK:
+ // need to match a token
+ tok_kind = rule->arg[i] & RULE_ARG_ARG_MASK;
+ if (py_lexer_is_kind(lex, tok_kind)) {
+ // matched token
+ if (tok_kind == PY_TOKEN_NAME) {
+ push_result_token(parser, lex);
+ }
+ py_lexer_to_next(lex);
+ } else {
+ // failed to match token
+ if (i > 0) {
+ // already eaten tokens so can't backtrack
+ goto syntax_error;
+ } else {
+ // this rule failed, so backtrack
+ backtrack = true;
+ goto next_rule;
+ }
+ }
+ break;
+ case RULE_ARG_RULE:
+ //if (i + 1 < n) {
+ push_rule(parser, rule, i + 1);
+ //}
+ push_rule_from_arg(parser, rule->arg[i]);
+ goto next_rule;
+ case RULE_ARG_OPT_RULE:
+ push_rule(parser, rule, i + 1);
+ push_rule_from_arg(parser, rule->arg[i]);
+ goto next_rule;
+ default:
+ assert(0);
+ }
+ }
+
+ assert(i == n);
+
+ // matched the rule, so now build the corresponding parse_node
+
+ // count number of arguments for the parse_node
+ i = 0;
+ emit_rule = false;
+ for (int x = 0; x < n; ++x) {
+ if ((rule->arg[x] & RULE_ARG_KIND_MASK) == RULE_ARG_TOK) {
+ tok_kind = rule->arg[x] & RULE_ARG_ARG_MASK;
+ if (tok_kind >= PY_TOKEN_NAME) {
+ emit_rule = true;
+ }
+ if (tok_kind == PY_TOKEN_NAME) {
+ // only tokens which were names are pushed to stack
+ i += 1;
+ }
+ } else {
+ // rules are always pushed
+ i += 1;
+ }
+ }
+
+ // always emit these rules, even if they have only 1 argument
+ if (rule->rule_id == RULE_expr_stmt || rule->rule_id == RULE_yield_stmt) {
+ emit_rule = true;
+ }
+
+ // never emit these rules if they have only 1 argument
+ // NOTE: can't put atom_paren here because we need it to distinguisg, for example, [a,b] from [(a,b)]
+ if (rule->rule_id == RULE_else_stmt || rule->rule_id == RULE_testlist_comp_3b || rule->rule_id == RULE_import_as_names_paren || rule->rule_id == RULE_typedargslist_colon || rule->rule_id == RULE_typedargslist_equal || rule->rule_id == RULE_dictorsetmaker_colon || rule->rule_id == RULE_classdef_2 || rule->rule_id == RULE_with_item_as || rule->rule_id == RULE_assert_stmt_extra || rule->rule_id == RULE_as_name || rule->rule_id == RULE_raise_stmt_from || rule->rule_id == RULE_vfpdef) {
+ emit_rule = false;
+ }
+
+ // always emit these rules, and add an extra blank node at the end (to be used by the compiler to store data)
+ if (rule->rule_id == RULE_funcdef || rule->rule_id == RULE_classdef || rule->rule_id == RULE_comp_for || rule->rule_id == RULE_lambdef || rule->rule_id == RULE_lambdef_nocond) {
+ emit_rule = true;
+ push_result_node(parser, PY_PARSE_NODE_NULL);
+ i += 1;
+ }
+
+ int num_not_nil = 0;
+ for (int x = 0; x < i; ++x) {
+ if (peek_result(parser, x) != PY_PARSE_NODE_NULL) {
+ num_not_nil += 1;
+ }
+ }
+ //printf("done and %s n=%d i=%d notnil=%d\n", rule->rule_name, n, i, num_not_nil);
+ if (emit_rule) {
+ push_result_rule(parser, rule, i);
+ } else if (num_not_nil == 0) {
+ push_result_rule(parser, rule, i); // needed for, eg, atom_paren, testlist_comp_3b
+ //result_stack_show(parser);
+ //assert(0);
+ } else if (num_not_nil == 1) {
+ // single result, leave it on stack
+ py_parse_node_t pn = PY_PARSE_NODE_NULL;
+ for (int x = 0; x < i; ++x) {
+ py_parse_node_t pn2 = pop_result(parser);
+ if (pn2 != PY_PARSE_NODE_NULL) {
+ pn = pn2;
+ }
+ }
+ push_result_node(parser, pn);
+ } else {
+ push_result_rule(parser, rule, i);
+ }
+ break;
+
+ case RULE_ACT_LIST:
+ // n=2 is: item item*
+ // n=1 is: item (sep item)*
+ // n=3 is: item (sep item)* [sep]
+ if (backtrack) {
+ list_backtrack:
+ had_trailing_sep = false;
+ if (n == 2) {
+ if (i == 1) {
+ // fail on item, first time round; propagate backtrack
+ goto next_rule;
+ } else {
+ // fail on item, in later rounds; finish with this rule
+ backtrack = false;
+ }
+ } else {
+ if (i == 1) {
+ // fail on item, first time round; propagate backtrack
+ goto next_rule;
+ } else if ((i & 1) == 1) {
+ // fail on item, in later rounds; have eaten tokens so can't backtrack
+ if (n == 3) {
+ // list allows trailing separator; finish parsing list
+ had_trailing_sep = true;
+ backtrack = false;
+ } else {
+ // list doesn't allowing trailing separator; fail
+ goto syntax_error;
+ }
+ } else {
+ // fail on separator; finish parsing list
+ backtrack = false;
+ }
+ }
+ } else {
+ for (;;) {
+ uint arg = rule->arg[i & 1 & n];
+ switch (arg & RULE_ARG_KIND_MASK) {
+ case RULE_ARG_TOK:
+ if (py_lexer_is_kind(lex, arg & RULE_ARG_ARG_MASK)) {
+ if (i & 1 & n) {
+ // separators which are tokens are not pushed to result stack
+ } else {
+ push_result_token(parser, lex);
+ }
+ py_lexer_to_next(lex);
+ // got element of list, so continue parsing list
+ i += 1;
+ } else {
+ // couldn't get element of list
+ i += 1;
+ backtrack = true;
+ goto list_backtrack;
+ }
+ break;
+ case RULE_ARG_RULE:
+ push_rule(parser, rule, i + 1);
+ push_rule_from_arg(parser, arg);
+ goto next_rule;
+ default:
+ assert(0);
+ }
+ }
+ }
+ assert(i >= 1);
+
+ // compute number of elements in list, result in i
+ i -= 1;
+ if ((n & 1) && (rule->arg[1] & RULE_ARG_KIND_MASK) == RULE_ARG_TOK) {
+ // don't count separators when they are tokens
+ i = (i + 1) / 2;
+ }
+
+ if (i == 1) {
+ // list matched single item
+ if (had_trailing_sep) {
+ // if there was a trailing separator, make a list of a single item
+ push_result_rule(parser, rule, i);
+ } else {
+ // just leave single item on stack (ie don't wrap in a list)
+ }
+ } else {
+ //printf("done list %s %d %d\n", rule->rule_name, n, i);
+ push_result_rule(parser, rule, i);
+ }
+ break;
+
+ default:
+ assert(0);
+ }
+ }
+ if (!py_lexer_is_kind(lex, PY_TOKEN_END)) {
+ py_lexer_show_error(lex, "unexpected token at end:");
+ py_token_show(py_lexer_cur(lex));
+ }
+ //printf("--------------\n");
+ //result_stack_show(parser);
+ assert(parser->result_stack_top == 1);
+ //printf("maximum depth: %d\n", parser->rule_stack_alloc);
+ //printf("number of parse nodes allocated: %d\n", num_parse_nodes_allocated);
+ return parser->result_stack[0];
+
+syntax_error:
+ py_lexer_show_error(lex, "syntax error:");
+#ifdef USE_RULE_NAME
+ py_lexer_show_error(lex, rule->rule_name);
+#endif
+ py_token_show(py_lexer_cur(lex));
+ return PY_PARSE_NODE_NULL;
+}