1 /*
2  * Copyright (c) 2001-2016 Stephen Williams (steve@icarus.com)
3  *
4  *    This source code is free software; you can redistribute it
5  *    and/or modify it in source code form under the terms of the GNU
6  *    General Public License as published by the Free Software
7  *    Foundation; either version 2 of the License, or (at your option)
8  *    any later version.
9  *
10  *    This program is distributed in the hope that it will be useful,
11  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *    GNU General Public License for more details.
14  *
15  *    You should have received a copy of the GNU General Public License
16  *    along with this program; if not, write to the Free Software
17  *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18  */
19 
20 # include  "codes.h"
21 # include  "statistics.h"
22 # include  "config.h"
23 #ifdef CHECK_WITH_VALGRIND
24 # include  "vvp_cleanup.h"
25 #endif
26 # include  <cstring>
27 # include  <cassert>
28 
29 /*
30  * The code space is broken into chunks, to make for efficient
31  * allocation of large amounts. Each chunk is an array of vvp_code_s
32  * structures, with the last opcode loaded with an of_CHUNK_LINK
33  * instruction to branch to the next chunk. This handles the case
34  * where the program counter steps off the end of a chunk.
35  */
36 const unsigned code_chunk_size = 1024;
37 
38 static struct vvp_code_s *first_chunk = 0;
39 static struct vvp_code_s *current_chunk = 0;
40 static unsigned current_within_chunk = 0;
41 
42 /*
43  * This initializes the code space. It sets up the first code chunk,
44  * and places at address 0 a ZOMBIE instruction.
45  */
codespace_init(void)46 void codespace_init(void)
47 {
48       assert(current_chunk == 0);
49       first_chunk = new struct vvp_code_s [code_chunk_size];
50       current_chunk = first_chunk;
51 
52       current_chunk[0].opcode = &of_ZOMBIE;
53 
54       current_chunk[code_chunk_size-1].opcode = &of_CHUNK_LINK;
55       current_chunk[code_chunk_size-1].cptr = 0;
56 
57       current_within_chunk = 1;
58 
59       count_opcodes = 0;
60       size_opcodes += code_chunk_size * sizeof (struct vvp_code_s);
61 }
62 
codespace_next(void)63 vvp_code_t codespace_next(void)
64 {
65       if (current_within_chunk == (code_chunk_size-1)) {
66 	    current_chunk[code_chunk_size-1].cptr
67 		  = new struct vvp_code_s [code_chunk_size];
68 	    current_chunk = current_chunk[code_chunk_size-1].cptr;
69 
70 	      /* Put a link opcode on the end of the chunk. */
71 	    current_chunk[code_chunk_size-1].opcode = &of_CHUNK_LINK;
72 	    current_chunk[code_chunk_size-1].cptr   = 0;
73 
74 	    current_within_chunk = 0;
75 
76 	    size_opcodes += code_chunk_size * sizeof (struct vvp_code_s);
77       }
78 
79       vvp_code_t res = current_chunk + current_within_chunk;
80       return res;
81 }
82 
codespace_allocate(void)83 vvp_code_t codespace_allocate(void)
84 {
85       vvp_code_t res = codespace_next();
86       current_within_chunk += 1;
87       count_opcodes += 1;
88 
89       memset(res, 0, sizeof(*res));
90 
91       return res;
92 }
93 
codespace_null(void)94 vvp_code_t codespace_null(void)
95 {
96       return first_chunk + 0;
97 }
98 
99 #ifdef CHECK_WITH_VALGRIND
codespace_delete(void)100 void codespace_delete(void)
101 {
102       vvp_code_t cur = first_chunk;
103 
104 	/* If there are no opcodes then just delete the code space. */
105       if (count_opcodes == 0) {
106 	    delete [] cur;
107 	    return;
108       }
109 
110       do {
111 	    vvp_code_t next = cur[code_chunk_size-1].cptr;
112 	    for (unsigned idx = 0 ; idx < code_chunk_size; idx += 1) {
113 		  count_opcodes -= 1;
114 		  if ((cur+idx)->opcode == &of_VPI_CALL) {
115 			vpi_call_delete((cur+idx)->handle);
116 		  } else if (((cur+idx)->opcode == &of_EXEC_UFUNC_REAL) ||
117 		             ((cur+idx)->opcode == &of_EXEC_UFUNC_VEC4)) {
118 			exec_ufunc_delete((cur+idx));
119 		  } else if ((cur+idx)->opcode == &of_FILE_LINE) {
120 			delete((cur+idx)->handle);
121 		  } else if (((cur+idx)->opcode == &of_CONCATI_STR) ||
122 		             ((cur+idx)->opcode == &of_NEW_DARRAY) ||
123 		             ((cur+idx)->opcode == &of_PUSHI_STR)) {
124 			delete [] ((cur+idx)->text);
125 		  }
126 		  if (count_opcodes == 0) break;
127 	    }
128 	      /* Don't count the &of_CHUNK_LINK opcode. */
129 	    if (count_opcodes != 0) count_opcodes += 1;
130 	    delete [] cur;
131 	    cur = next;
132       } while (cur != 0);
133 }
134 #endif
135