ack/util/mcgg/sample5.brg
2016-09-20 20:37:16 +02:00

85 lines
1.8 KiB
Text

%{
#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
#define TRACE
enum { MOVE=1, MEM=2, PLUS=3, NAME=4, CONST=6 };
#define STATE_TYPE void*
typedef struct tree {
int op;
struct tree *kids[2];
STATE_TYPE state_label;
} *NODEPTR_TYPE;
#define OP_LABEL(p) ((p)->op)
#define LEFT_CHILD(p) ((p)->kids[0])
#define RIGHT_CHILD(p) ((p)->kids[1])
#define STATE_LABEL(p) ((p)->state_label)
#define PANIC printf
static void burm_trace(NODEPTR_TYPE p, int eruleno, int cost, int bestcost) {
#ifdef TRACE
extern char *burm_string[];
fprintf(stderr, "0x%p matched %s with cost %d vs. %d\n", p,
burm_string[eruleno], cost, bestcost);
#endif
}
%}
%term MOVE=1 MEM=2 PLUS=3 NAME=4 CONST=6
%%
stm: MOVE(MEM(loc),reg) = 1 (4);
reg: PLUS(con,reg) = 2 (3);
reg: PLUS(reg,reg) = 3 (2);
reg: PLUS(MEM(loc),reg) = 4 (4);
reg: MEM(loc) = 5 (4);
reg: con = 6 (2);
loc: reg = 7;
loc: NAME = 8;
loc: PLUS(NAME,reg) = 9;
con: CONST = 10;
%%
static void dumpCover(NODEPTR_TYPE p, int goalnt, int indent) {
#ifdef TRACE
int eruleno = burm_rule(STATE_LABEL(p), goalnt);
short *nts = burm_nts[eruleno];
NODEPTR_TYPE kids[10];
int i;
for (i = 0; i < indent; i++)
fprintf(stderr, " ");
fprintf(stderr, "%s\n", burm_string[eruleno]);
burm_kids(p, eruleno, kids);
for (i = 0; nts[i]; i++)
dumpCover(kids[i], nts[i], indent + 1);
#endif
}
static NODEPTR_TYPE tree(int op, NODEPTR_TYPE l, NODEPTR_TYPE r) {
NODEPTR_TYPE p = malloc(sizeof *p);
assert(p);
p->op = op;
p->kids[0] = l; p->kids[1] = r;
return p;
}
main(void) {
NODEPTR_TYPE p;
p = tree(MOVE,
tree(MEM, tree(NAME, 0, 0), 0),
tree(PLUS,
tree(MEM, tree(PLUS,
tree(NAME, 0, 0),
tree(MEM, tree(NAME, 0, 0), 0)), 0),
tree(CONST, 0, 0) ) );
burm_label(p);
dumpCover(p, 1, 0);
return 0;
}