File:
[gforth] /
gforth /
vmgen-ex2 /
peephole.c
Revision
1.1:
download - view:
text,
annotated -
select for diffs
Sun Jun 2 15:46:18 2002 UTC (21 years, 10 months ago) by
anton
Branches:
MAIN
CVS tags:
HEAD
vmgen-related changes:
in prims2x:
Conversion macros for single items now take 2 arguments
Converting from two items to a type has changed order
argument printing for disassembler disabled (for now)
disassembler now also uses VM_IS_INST
in Gforth and vmgen-ex: adapted to work with changed prims2x
new: vmgen-ex2: uses union for Cell instead of casting (lots of
changes compared to vmgen-ex)
1: /* Peephole optimization routines and tables
2:
3: Copyright (C) 2001 Free Software Foundation, Inc.
4:
5: This file is part of Gforth.
6:
7: Gforth is free software; you can redistribute it and/or
8: modify it under the terms of the GNU General Public License
9: as published by the Free Software Foundation; either version 2
10: of the License, or (at your option) any later version.
11:
12: This program is distributed in the hope that it will be useful,
13: but WITHOUT ANY WARRANTY; without even the implied warranty of
14: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15: GNU General Public License for more details.
16:
17: You should have received a copy of the GNU General Public License
18: along with this program; if not, write to the Free Software
19: Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
20: */
21:
22: #include <stdlib.h>
23: #include "mini.h"
24:
25: /* the numbers in this struct are primitive indices */
26: typedef struct Combination {
27: int prefix;
28: int lastprim;
29: int combination_prim;
30: } Combination;
31:
32: Combination peephole_table[] = {
33: #include "mini-peephole.i"
34: };
35:
36: int use_super = 1;
37:
38: typedef struct Peeptable_entry {
39: struct Peeptable_entry *next;
40: Label prefix;
41: Label lastprim;
42: Label combination_prim;
43: } Peeptable_entry;
44:
45: #define HASH_SIZE 1024
46: #define hash(_i1,_i2) (((((long)(_i1))^((long)(_i2)))>>4)&(HASH_SIZE-1))
47:
48: struct Peeptable_entry **peeptable;
49:
50: Peeptable_entry **prepare_peephole_table(Label insts[])
51: {
52: long i;
53: Peeptable_entry **pt = (Peeptable_entry **)calloc(HASH_SIZE,sizeof(Peeptable_entry *));
54:
55: for (i=0; i<sizeof(peephole_table)/sizeof(peephole_table[0]); i++) {
56: Combination *c = &peephole_table[i];
57: Peeptable_entry *p = (Peeptable_entry *)malloc(sizeof(Peeptable_entry));
58: long h;
59: p->prefix = insts[c->prefix];
60: p->lastprim = insts[c->lastprim];
61: p->combination_prim = insts[c->combination_prim];
62: h = hash((p->prefix),(p->lastprim));
63: p->next = pt[h];
64: pt[h] = p;
65: }
66: return pt;
67: }
68:
69: void init_peeptable(void)
70: {
71: peeptable = prepare_peephole_table(vm_prim);
72: }
73:
74: Label peephole_opt(Label inst1, Label inst2, Peeptable_entry **peeptable)
75: {
76: Peeptable_entry **pt = (Peeptable_entry **)peeptable;
77: Peeptable_entry *p;
78:
79: if (use_super == 0)
80: return NULL;
81: for (p = pt[hash(inst1,inst2)]; p != NULL; p = p->next)
82: if (inst1 == p->prefix && inst2 == p->lastprim)
83: return p->combination_prim;
84: return NULL;
85: }
86:
87: Inst *last_compiled = NULL;
88:
89: void gen_inst(Inst **vmcodepp, Label i)
90: {
91: if (last_compiled != NULL) {
92: Label combo = peephole_opt((*last_compiled).inst, i, peeptable);
93: if (combo != NULL) {
94: (*last_compiled).inst = combo;
95: return;
96: }
97: }
98: last_compiled = *vmcodepp;
99: (**vmcodepp).inst = i;
100: (*vmcodepp)++;
101: }
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>