sys/libkern/mcount.c

54  * program's call graph edges.  frompc and selfpc are the return
58  * both frompcindex and frompc.  Any reasonable, modern compiler will
62 _MCOUNT_DECL(uintfptr_t frompc, uintfptr_t selfpc)
94 	MCOUNT_DETRAMP(frompc);
98 	 * When we are called from an exception handler, frompc may be
99 	 * a user address.  Convert such frompc's to some representation
103 	frompc = MCOUNT_FROMPC_USER(frompc);
110 	if (frompc < p->lowpc || frompc - p->lowpc >= p->textsize)
111 		frompc = MCOUNT_USERPC;
115 	frompci = frompc - p->lowpc;
123 		 * against `frompc'.  Compensate for overheads.
151 	 * When we are called from an exception handler, frompc is faked
158 	frompc = MCOUNT_FROMPC_INTR(selfpc);
159 	if ((frompc - p->lowpc) < p->textsize)
160 		frompci = frompc - p->lowpc;
164 	 * check that frompc is a reasonable pc value.