1 #include <u.h>
2 #include <libc.h>
3 #include <bio.h>
4 #include <mach.h>
5 
6 /*
7  * XXX could remove the rock by hiding it in a special regs.
8  * That would still be sleazy but would be thread-safe.
9  */
10 
11 static struct {
12 	int found;
13 	int nframe;
14 	Loc l;
15 	char *fn;
16 	char *var;
17 	char *reg;
18 } rock;
19 
20 static int
21 ltrace(Map *map, Regs *regs, u64int pc, u64int nextpc, Symbol *sym, int depth)
22 {
23 	u64int v;
24 	Symbol s1;
25 
26 	USED(pc);
27 	USED(nextpc);
28 	USED(depth);
29 
30 	if(sym==nil || strcmp(sym->name, rock.fn) != 0)
31 		return ++rock.nframe < 40;
32 	if(rock.reg){
33 		if(rget(regs, rock.reg, &v) < 0)
34 			return 0;
35 		rock.l = locconst(v);
36 		rock.found = 1;
37 		return 0;
38 	}
39 	if(lookuplsym(sym, rock.var, &s1) < 0)
40 		return 0;
41 	if(locsimplify(map, regs, s1.loc, &rock.l) < 0)
42 		return 0;
43 	if(rock.l.type == LREG && rget(regs, rock.l.reg, &v) >= 0)
44 		rock.l = locconst(v);
45 	if(rock.l.type != LADDR && rock.l.type != LCONST)
46 		return 0;
47 	rock.found = 1;
48 	return 0;
49 }
50 
51 int
52 localaddr(Map *map, Regs *regs, char *fn, char *var, u64int *val)
53 {
54 	Regdesc *rp;
55 
56 	rock.found = 0;
57 	rock.nframe = 0;
58 	rock.fn = fn;
59 	rock.reg = nil;
60 	rock.var = nil;
61 	for(rp=mach->reglist; rp->name; rp++)
62 		if(strcmp(rp->name, var) == 0)
63 			rock.reg = rp->name;
64 	if(!rock.reg)
65 		rock.var = var;
66 	stacktrace(map, regs, ltrace);
67 	if(rock.found){
68 		*val = rock.l.addr;
69 		return 0;
70 	}
71 	return -1;
72 }