/* Restore a value from the trace exit state. */ static void snap_restoreval(jit_State *J, GCtrace *T, ExitState *ex, SnapNo snapno, BloomFilter rfilt, IRRef ref, TValue *o) { IRIns *ir = &T->ir[ref]; IRType1 t = ir->t; RegSP rs = ir->prev; if (irref_isk(ref)) { /* Restore constant slot. */ lj_ir_kvalue(J->L, o, ir); return; } if (LJ_UNLIKELY(bloomtest(rfilt, ref))) rs = snap_renameref(T, snapno, ref, rs); if (ra_hasspill(regsp_spill(rs))) { /* Restore from spill slot. */ int32_t *sps = &ex->spill[regsp_spill(rs)]; if (irt_isinteger(t)) { setintV(o, *sps); #if !LJ_SOFTFP } else if (irt_isnum(t)) { o->u64 = *(uint64_t *)sps; #endif } else if (LJ_64 && irt_islightud(t)) { /* 64 bit lightuserdata which may escape already has the tag bits. */ o->u64 = *(uint64_t *)sps; } else { lua_assert(!irt_ispri(t)); /* PRI refs never have a spill slot. */ setgcrefi(o->gcr, *sps); setitype(o, irt_toitype(t)); } } else { /* Restore from register. */ Reg r = regsp_reg(rs); if (ra_noreg(r)) { lua_assert(ir->o == IR_CONV && ir->op2 == IRCONV_NUM_INT); snap_restoreval(J, T, ex, snapno, rfilt, ir->op1, o); if (LJ_DUALNUM) setnumV(o, (lua_Number)intV(o)); return; } else if (irt_isinteger(t)) { setintV(o, (int32_t)ex->gpr[r-RID_MIN_GPR]); #if !LJ_SOFTFP } else if (irt_isnum(t)) { setnumV(o, ex->fpr[r-RID_MIN_FPR]); #endif } else if (LJ_64 && irt_islightud(t)) { /* 64 bit lightuserdata which may escape already has the tag bits. */ o->u64 = ex->gpr[r-RID_MIN_GPR]; } else { if (!irt_ispri(t)) setgcrefi(o->gcr, ex->gpr[r-RID_MIN_GPR]); setitype(o, irt_toitype(t)); } } }
/* Restore interpreter state from exit state with the help of a snapshot. */ const BCIns *lj_snap_restore(jit_State *J, void *exptr) { ExitState *ex = (ExitState *)exptr; SnapNo snapno = J->exitno; /* For now, snapno == exitno. */ GCtrace *T = traceref(J, J->parent); SnapShot *snap = &T->snap[snapno]; MSize n, nent = snap->nent; SnapEntry *map = &T->snapmap[snap->mapofs]; SnapEntry *flinks = map + nent + snap->depth; int32_t ftsz0; BCReg nslots = snap->nslots; TValue *frame; BloomFilter rfilt = snap_renamefilter(T, snapno); const BCIns *pc = snap_pc(map[nent]); lua_State *L = J->L; /* Set interpreter PC to the next PC to get correct error messages. */ setcframe_pc(cframe_raw(L->cframe), pc+1); /* Make sure the stack is big enough for the slots from the snapshot. */ if (LJ_UNLIKELY(L->base + nslots > tvref(L->maxstack))) { L->top = curr_topL(L); lj_state_growstack(L, nslots - curr_proto(L)->framesize); } /* Fill stack slots with data from the registers and spill slots. */ frame = L->base-1; ftsz0 = frame_ftsz(frame); /* Preserve link to previous frame in slot #0. */ for (n = 0; n < nent; n++) { SnapEntry sn = map[n]; IRRef ref = snap_ref(sn); BCReg s = snap_slot(sn); TValue *o = &frame[s]; /* Stack slots are relative to start frame. */ IRIns *ir = &T->ir[ref]; if (irref_isk(ref)) { /* Restore constant slot. */ lj_ir_kvalue(L, o, ir); if ((sn & (SNAP_CONT|SNAP_FRAME))) { /* Overwrite tag with frame link. */ o->fr.tp.ftsz = s != 0 ? (int32_t)*flinks-- : ftsz0; if ((sn & SNAP_FRAME)) { GCfunc *fn = ir_kfunc(ir); if (isluafunc(fn)) { MSize framesize = funcproto(fn)->framesize; L->base = ++o; if (LJ_UNLIKELY(o + framesize > tvref(L->maxstack))) { ptrdiff_t fsave = savestack(L, frame); L->top = o; lj_state_growstack(L, framesize); /* Grow again. */ frame = restorestack(L, fsave); } } } } } else if (!(sn & SNAP_NORESTORE)) { IRType1 t = ir->t; RegSP rs = ir->prev; lua_assert(!(sn & (SNAP_CONT|SNAP_FRAME))); if (LJ_UNLIKELY(bloomtest(rfilt, ref))) rs = snap_renameref(T, snapno, ref, rs); if (ra_hasspill(regsp_spill(rs))) { /* Restore from spill slot. */ int32_t *sps = &ex->spill[regsp_spill(rs)]; if (LJ_SOFTFP && (sn & SNAP_SOFTFPNUM)) { o->u32.lo = (uint32_t)*sps; } else if (irt_isinteger(t)) { setintV(o, *sps); #if !LJ_SOFTFP } else if (irt_isnum(t)) { o->u64 = *(uint64_t *)sps; #endif #if LJ_64 } else if (irt_islightud(t)) { /* 64 bit lightuserdata which may escape already has the tag bits. */ o->u64 = *(uint64_t *)sps; #endif } else { lua_assert(!irt_ispri(t)); /* PRI refs never have a spill slot. */ setgcrefi(o->gcr, *sps); setitype(o, irt_toitype(t)); } } else { /* Restore from register. */ Reg r = regsp_reg(rs); lua_assert(ra_hasreg(r)); if (LJ_SOFTFP && (sn & SNAP_SOFTFPNUM)) { o->u32.lo = (uint32_t)ex->gpr[r-RID_MIN_GPR]; } else if (irt_isinteger(t)) { setintV(o, (int32_t)ex->gpr[r-RID_MIN_GPR]); #if !LJ_SOFTFP } else if (irt_isnum(t)) { setnumV(o, ex->fpr[r-RID_MIN_FPR]); #endif #if LJ_64 } else if (irt_islightud(t)) { /* 64 bit lightuserdata which may escape already has the tag bits. */ o->u64 = ex->gpr[r-RID_MIN_GPR]; #endif } else { if (!irt_ispri(t)) setgcrefi(o->gcr, ex->gpr[r-RID_MIN_GPR]); setitype(o, irt_toitype(t)); } } if (LJ_SOFTFP && (sn & SNAP_SOFTFPNUM)) { rs = (ir+1)->prev; if (LJ_UNLIKELY(bloomtest(rfilt, ref+1))) rs = snap_renameref(T, snapno, ref+1, rs); o->u32.hi = (ra_hasspill(regsp_spill(rs))) ? (uint32_t)*&ex->spill[regsp_spill(rs)] : (uint32_t)ex->gpr[regsp_reg(rs)-RID_MIN_GPR]; } } } switch (bc_op(*pc)) { case BC_CALLM: case BC_CALLMT: case BC_RETM: case BC_TSETM: L->top = frame + nslots; break; default: L->top = curr_topL(L); break; } lua_assert(map + nent == flinks); return pc; }