/* Set/reset protection to allow patching of MCode areas. */
MCode *lj_mcode_patch(jit_State *J, MCode *ptr, int finish)
{
#ifdef LUAJIT_UNPROTECT_MCODE
UNUSED(J); UNUSED(ptr); UNUSED(finish);
return NULL;
#else
if (finish) {
if (J->mcarea == ptr)
mcode_protect(J, MCPROT_RUN);
else if (LJ_UNLIKELY(mcode_setprot(ptr, ((MCLink *)ptr)->size, MCPROT_RUN)))
mcode_protfail(J);
return NULL;
} else {
MCode *mc = J->mcarea;
/* Try current area first to use the protection cache. */
if (ptr >= mc && ptr < (MCode *)((char *)mc + J->szmcarea)) {
mcode_protect(J, MCPROT_GEN);
return mc;
}
/* Otherwise search through the list of MCode areas. */
for (;;) {
mc = ((MCLink *)mc)->next;
lua_assert(mc != NULL);
if (ptr >= mc && ptr < (MCode *)((char *)mc + ((MCLink *)mc)->size)) {
if (LJ_UNLIKELY(mcode_setprot(mc, ((MCLink *)mc)->size, MCPROT_GEN)))
mcode_protfail(J);
return mc;
}
}
}
#endif
}
/* Reserve the remainder of the current MCode area. */
MCode *lj_mcode_reserve(jit_State *J, MCode **lim)
{
if (!J->mcarea)
mcode_allocarea(J);
else
mcode_protect(J, MCPROT_GEN);
*lim = J->mcbot;
return J->mctop;
}
/* Abort the reservation. */
void lj_mcode_abort(jit_State *J)
{
if (J->mcarea)
mcode_protect(J, MCPROT_RUN);
}
/* Commit the top part of the current MCode area. */
void lj_mcode_commit(jit_State *J, MCode *top)
{
J->mctop = top;
mcode_protect(J, MCPROT_RUN);
}
/* Abort the reservation. */
void lj_mcode_abort(jit_State *J)
{
mcode_protect(J, MCPROT_RUN);
}
