Python code coverage for Parser/acceler.c

#	count	content
1	n/a
2	n/a	/* Parser accelerator module */
3	n/a
4	n/a	/* The parser as originally conceived had disappointing performance.
5	n/a	This module does some precomputation that speeds up the selection
6	n/a	of a DFA based upon a token, turning a search through an array
7	n/a	into a simple indexing operation. The parser now cannot work
8	n/a	without the accelerators installed. Note that the accelerators
9	n/a	are installed dynamically when the parser is initialized, they
10	n/a	are not part of the static data structure written on graminit.[ch]
11	n/a	by the parser generator. */
12	n/a
13	n/a	#include "pgenheaders.h"
14	n/a	#include "grammar.h"
15	n/a	#include "node.h"
16	n/a	#include "token.h"
17	n/a	#include "parser.h"
18	n/a
19	n/a	/* Forward references */
20	n/a	static void fixdfa(grammar , dfa );
21	n/a	static void fixstate(grammar , state );
22	n/a
23	n/a	void
24	n/a	PyGrammar_AddAccelerators(grammar *g)
25	n/a	{
26	n/a	dfa *d;
27	n/a	int i;
28	n/a	d = g->g_dfa;
29	n/a	for (i = g->g_ndfas; --i >= 0; d++)
30	n/a	fixdfa(g, d);
31	n/a	g->g_accel = 1;
32	n/a	}
33	n/a
34	n/a	void
35	n/a	PyGrammar_RemoveAccelerators(grammar *g)
36	n/a	{
37	n/a	dfa *d;
38	n/a	int i;
39	n/a	g->g_accel = 0;
40	n/a	d = g->g_dfa;
41	n/a	for (i = g->g_ndfas; --i >= 0; d++) {
42	n/a	state *s;
43	n/a	int j;
44	n/a	s = d->d_state;
45	n/a	for (j = 0; j < d->d_nstates; j++, s++) {
46	n/a	if (s->s_accel)
47	n/a	PyObject_FREE(s->s_accel);
48	n/a	s->s_accel = NULL;
49	n/a	}
50	n/a	}
51	n/a	}
52	n/a
53	n/a	static void
54	n/a	fixdfa(grammar g, dfa d)
55	n/a	{
56	n/a	state *s;
57	n/a	int j;
58	n/a	s = d->d_state;
59	n/a	for (j = 0; j < d->d_nstates; j++, s++)
60	n/a	fixstate(g, s);
61	n/a	}
62	n/a
63	n/a	static void
64	n/a	fixstate(grammar g, state s)
65	n/a	{
66	n/a	arc *a;
67	n/a	int k;
68	n/a	int *accel;
69	n/a	int nl = g->g_ll.ll_nlabels;
70	n/a	s->s_accept = 0;
71	n/a	accel = (int ) PyObject_MALLOC(nl sizeof(int));
72	n/a	if (accel == NULL) {
73	n/a	fprintf(stderr, "no mem to build parser accelerators\n");
74	n/a	exit(1);
75	n/a	}
76	n/a	for (k = 0; k < nl; k++)
77	n/a	accel[k] = -1;
78	n/a	a = s->s_arc;
79	n/a	for (k = s->s_narcs; --k >= 0; a++) {
80	n/a	int lbl = a->a_lbl;
81	n/a	label *l = &g->g_ll.ll_label[lbl];
82	n/a	int type = l->lb_type;
83	n/a	if (a->a_arrow >= (1 << 7)) {
84	n/a	printf("XXX too many states!\n");
85	n/a	continue;
86	n/a	}
87	n/a	if (ISNONTERMINAL(type)) {
88	n/a	dfa *d1 = PyGrammar_FindDFA(g, type);
89	n/a	int ibit;
90	n/a	if (type - NT_OFFSET >= (1 << 7)) {
91	n/a	printf("XXX too high nonterminal number!\n");
92	n/a	continue;
93	n/a	}
94	n/a	for (ibit = 0; ibit < g->g_ll.ll_nlabels; ibit++) {
95	n/a	if (testbit(d1->d_first, ibit)) {
96	n/a	if (accel[ibit] != -1)
97	n/a	printf("XXX ambiguity!\n");
98	n/a	accel[ibit] = a->a_arrow \| (1 << 7) \|
99	n/a	((type - NT_OFFSET) << 8);
100	n/a	}
101	n/a	}
102	n/a	}
103	n/a	else if (lbl == EMPTY)
104	n/a	s->s_accept = 1;
105	n/a	else if (lbl >= 0 && lbl < nl)
106	n/a	accel[lbl] = a->a_arrow;
107	n/a	}
108	n/a	while (nl > 0 && accel[nl-1] == -1)
109	n/a	nl--;
110	n/a	for (k = 0; k < nl && accel[k] == -1;)
111	n/a	k++;
112	n/a	if (k < nl) {
113	n/a	int i;
114	n/a	s->s_accel = (int ) PyObject_MALLOC((nl-k) sizeof(int));
115	n/a	if (s->s_accel == NULL) {
116	n/a	fprintf(stderr, "no mem to add parser accelerators\n");
117	n/a	exit(1);
118	n/a	}
119	n/a	s->s_lower = k;
120	n/a	s->s_upper = nl;
121	n/a	for (i = 0; k < nl; i++, k++)
122	n/a	s->s_accel[i] = accel[k];
123	n/a	}
124	n/a	PyObject_FREE(accel);
125	n/a	}