tools/wrk/deps/luajit/src/lj_asm_x86.h
/*
** x86/x64 IR assembler (SSA IR -> machine code).
** Copyright (C) 2005-2013 Mike Pall. See Copyright Notice in luajit.h
*/
/* -- Guard handling ------------------------------------------------------ */
/* Generate an exit stub group at the bottom of the reserved MCode memory. */
static MCode *asm_exitstub_gen(ASMState *as, ExitNo group)
{
ExitNo i, groupofs = (group*EXITSTUBS_PER_GROUP) & 0xff;
MCode *mxp = as->mcbot;
MCode *mxpstart = mxp;
if (mxp + (2+2)*EXITSTUBS_PER_GROUP+8+5 >= as->mctop)
asm_mclimit(as);
/* Push low byte of exitno for each exit stub. */
*mxp++ = XI_PUSHi8; *mxp++ = (MCode)groupofs;
for (i = 1; i < EXITSTUBS_PER_GROUP; i++) {
*mxp++ = XI_JMPs; *mxp++ = (MCode)((2+2)*(EXITSTUBS_PER_GROUP - i) - 2);
*mxp++ = XI_PUSHi8; *mxp++ = (MCode)(groupofs + i);
}
/* Push the high byte of the exitno for each exit stub group. */
*mxp++ = XI_PUSHi8; *mxp++ = (MCode)((group*EXITSTUBS_PER_GROUP)>>8);
/* Store DISPATCH at original stack slot 0. Account for the two push ops. */
*mxp++ = XI_MOVmi;
*mxp++ = MODRM(XM_OFS8, 0, RID_ESP);
*mxp++ = MODRM(XM_SCALE1, RID_ESP, RID_ESP);
*mxp++ = 2*sizeof(void *);
*(int32_t *)mxp = ptr2addr(J2GG(as->J)->dispatch); mxp += 4;
/* Jump to exit handler which fills in the ExitState. */
*mxp++ = XI_JMP; mxp += 4;
*((int32_t *)(mxp-4)) = jmprel(mxp, (MCode *)(void *)lj_vm_exit_handler);
/* Commit the code for this group (even if assembly fails later on). */
lj_mcode_commitbot(as->J, mxp);
as->mcbot = mxp;
as->mclim = as->mcbot + MCLIM_REDZONE;
return mxpstart;
}
/* Setup all needed exit stubs. */
static void asm_exitstub_setup(ASMState *as, ExitNo nexits)
{
ExitNo i;
if (nexits >= EXITSTUBS_PER_GROUP*LJ_MAX_EXITSTUBGR)
lj_trace_err(as->J, LJ_TRERR_SNAPOV);
for (i = 0; i < (nexits+EXITSTUBS_PER_GROUP-1)/EXITSTUBS_PER_GROUP; i++)
if (as->J->exitstubgroup[i] == NULL)
as->J->exitstubgroup[i] = asm_exitstub_gen(as, i);
}
/* Emit conditional branch to exit for guard.
** It's important to emit this *after* all registers have been allocated,
** because rematerializations may invalidate the flags.
*/
static void asm_guardcc(ASMState *as, int cc)
{
MCode *target = exitstub_addr(as->J, as->snapno);
MCode *p = as->mcp;
if (LJ_UNLIKELY(p == as->invmcp)) {
as->loopinv = 1;
*(int32_t *)(p+1) = jmprel(p+5, target);
target = p;
cc ^= 1;
if (as->realign) {
emit_sjcc(as, cc, target);
return;
}
}
emit_jcc(as, cc, target);
}
/* -- Memory operand fusion ----------------------------------------------- */
/* Limit linear search to this distance. Avoids O(n^2) behavior. */
#define CONFLICT_SEARCH_LIM 31
/* Check if a reference is a signed 32 bit constant. */
static int asm_isk32(ASMState *as, IRRef ref, int32_t *k)
{
if (irref_isk(ref)) {
IRIns *ir = IR(ref);
if (ir->o != IR_KINT64) {
*k = ir->i;
return 1;
} else if (checki32((int64_t)ir_kint64(ir)->u64)) {
*k = (int32_t)ir_kint64(ir)->u64;
return 1;
}
}
return 0;
}
/* Check if there's no conflicting instruction between curins and ref.
** Also avoid fusing loads if there are multiple references.
*/
static int noconflict(ASMState *as, IRRef ref, IROp conflict, int noload)
{
IRIns *ir = as->ir;
IRRef i = as->curins;
if (i > ref + CONFLICT_SEARCH_LIM)
return 0; /* Give up, ref is too far away. */
while (--i > ref) {
if (ir[i].o == conflict)
return 0; /* Conflict found. */
else if (!noload && (ir[i].op1 == ref || ir[i].op2 == ref))
return 0;
}
return 1; /* Ok, no conflict. */
}
/* Fuse array base into memory operand. */
static IRRef asm_fuseabase(ASMState *as, IRRef ref)
{
IRIns *irb = IR(ref);
as->mrm.ofs = 0;
if (irb->o == IR_FLOAD) {
IRIns *ira = IR(irb->op1);
lua_assert(irb->op2 == IRFL_TAB_ARRAY);
/* We can avoid the FLOAD of t->array for colocated arrays. */
if (ira->o == IR_TNEW && ira->op1 <= LJ_MAX_COLOSIZE &&
!neverfuse(as) && noconflict(as, irb->op1, IR_NEWREF, 1)) {
as->mrm.ofs = (int32_t)sizeof(GCtab); /* Ofs to colocated array. */
return irb->op1; /* Table obj. */
}
} else if (irb->o == IR_ADD && irref_isk(irb->op2)) {
/* Fuse base offset (vararg load). */
as->mrm.ofs = IR(irb->op2)->i;
return irb->op1;
}
return ref; /* Otherwise use the given array base. */
}
/* Fuse array reference into memory operand. */
static void asm_fusearef(ASMState *as, IRIns *ir, RegSet allow)
{
IRIns *irx;
lua_assert(ir->o == IR_AREF);
as->mrm.base = (uint8_t)ra_alloc1(as, asm_fuseabase(as, ir->op1), allow);
irx = IR(ir->op2);
if (irref_isk(ir->op2)) {
as->mrm.ofs += 8*irx->i;
as->mrm.idx = RID_NONE;
} else {
rset_clear(allow, as->mrm.base);
as->mrm.scale = XM_SCALE8;
/* Fuse a constant ADD (e.g. t[i+1]) into the offset.
** Doesn't help much without ABCelim, but reduces register pressure.
*/
if (!LJ_64 && /* Has bad effects with negative index on x64. */
mayfuse(as, ir->op2) && ra_noreg(irx->r) &&
irx->o == IR_ADD && irref_isk(irx->op2)) {
as->mrm.ofs += 8*IR(irx->op2)->i;
as->mrm.idx = (uint8_t)ra_alloc1(as, irx->op1, allow);
} else {
as->mrm.idx = (uint8_t)ra_alloc1(as, ir->op2, allow);
}
}
}
/* Fuse array/hash/upvalue reference into memory operand.
** Caveat: this may allocate GPRs for the base/idx registers. Be sure to
** pass the final allow mask, excluding any GPRs used for other inputs.
** In particular: 2-operand GPR instructions need to call ra_dest() first!
*/
static void asm_fuseahuref(ASMState *as, IRRef ref, RegSet allow)
{
IRIns *ir = IR(ref);
if (ra_noreg(ir->r)) {
switch ((IROp)ir->o) {
case IR_AREF:
if (mayfuse(as, ref)) {
asm_fusearef(as, ir, allow);
return;
}
break;
case IR_HREFK:
if (mayfuse(as, ref)) {
as->mrm.base = (uint8_t)ra_alloc1(as, ir->op1, allow);
as->mrm.ofs = (int32_t)(IR(ir->op2)->op2 * sizeof(Node));
as->mrm.idx = RID_NONE;
return;
}
break;
case IR_UREFC:
if (irref_isk(ir->op1)) {
GCfunc *fn = ir_kfunc(IR(ir->op1));
GCupval *uv = &gcref(fn->l.uvptr[(ir->op2 >> 8)])->uv;
as->mrm.ofs = ptr2addr(&uv->tv);
as->mrm.base = as->mrm.idx = RID_NONE;
return;
}
break;
default:
lua_assert(ir->o == IR_HREF || ir->o == IR_NEWREF || ir->o == IR_UREFO ||
ir->o == IR_KKPTR);
break;
}
}
as->mrm.base = (uint8_t)ra_alloc1(as, ref, allow);
as->mrm.ofs = 0;
as->mrm.idx = RID_NONE;
}
/* Fuse FLOAD/FREF reference into memory operand. */
static void asm_fusefref(ASMState *as, IRIns *ir, RegSet allow)
{
lua_assert(ir->o == IR_FLOAD || ir->o == IR_FREF);
as->mrm.ofs = field_ofs[ir->op2];
as->mrm.idx = RID_NONE;
if (irref_isk(ir->op1)) {
as->mrm.ofs += IR(ir->op1)->i;
as->mrm.base = RID_NONE;
} else {
as->mrm.base = (uint8_t)ra_alloc1(as, ir->op1, allow);
}
}
/* Fuse string reference into memory operand. */
static void asm_fusestrref(ASMState *as, IRIns *ir, RegSet allow)
{
IRIns *irr;
lua_assert(ir->o == IR_STRREF);
as->mrm.base = as->mrm.idx = RID_NONE;
as->mrm.scale = XM_SCALE1;
as->mrm.ofs = sizeof(GCstr);
if (irref_isk(ir->op1)) {
as->mrm.ofs += IR(ir->op1)->i;
} else {
Reg r = ra_alloc1(as, ir->op1, allow);
rset_clear(allow, r);
as->mrm.base = (uint8_t)r;
}
irr = IR(ir->op2);
if (irref_isk(ir->op2)) {
as->mrm.ofs += irr->i;
} else {
Reg r;
/* Fuse a constant add into the offset, e.g. string.sub(s, i+10). */
if (!LJ_64 && /* Has bad effects with negative index on x64. */
mayfuse(as, ir->op2) && irr->o == IR_ADD && irref_isk(irr->op2)) {
as->mrm.ofs += IR(irr->op2)->i;
r = ra_alloc1(as, irr->op1, allow);
} else {
r = ra_alloc1(as, ir->op2, allow);
}
if (as->mrm.base == RID_NONE)
as->mrm.base = (uint8_t)r;
else
as->mrm.idx = (uint8_t)r;
}
}
static void asm_fusexref(ASMState *as, IRRef ref, RegSet allow)
{
IRIns *ir = IR(ref);
as->mrm.idx = RID_NONE;
if (ir->o == IR_KPTR || ir->o == IR_KKPTR) {
as->mrm.ofs = ir->i;
as->mrm.base = RID_NONE;
} else if (ir->o == IR_STRREF) {
asm_fusestrref(as, ir, allow);
} else {
as->mrm.ofs = 0;
if (canfuse(as, ir) && ir->o == IR_ADD && ra_noreg(ir->r)) {
/* Gather (base+idx*sz)+ofs as emitted by cdata ptr/array indexing. */
IRIns *irx;
IRRef idx;
Reg r;
if (asm_isk32(as, ir->op2, &as->mrm.ofs)) { /* Recognize x+ofs. */
ref = ir->op1;
ir = IR(ref);
if (!(ir->o == IR_ADD && canfuse(as, ir) && ra_noreg(ir->r)))
goto noadd;
}
as->mrm.scale = XM_SCALE1;
idx = ir->op1;
ref = ir->op2;
irx = IR(idx);
if (!(irx->o == IR_BSHL || irx->o == IR_ADD)) { /* Try other operand. */
idx = ir->op2;
ref = ir->op1;
irx = IR(idx);
}
if (canfuse(as, irx) && ra_noreg(irx->r)) {
if (irx->o == IR_BSHL && irref_isk(irx->op2) && IR(irx->op2)->i <= 3) {
/* Recognize idx<<b with b = 0-3, corresponding to sz = (1),2,4,8. */
idx = irx->op1;
as->mrm.scale = (uint8_t)(IR(irx->op2)->i << 6);
} else if (irx->o == IR_ADD && irx->op1 == irx->op2) {
/* FOLD does idx*2 ==> idx<<1 ==> idx+idx. */
idx = irx->op1;
as->mrm.scale = XM_SCALE2;
}
}
r = ra_alloc1(as, idx, allow);
rset_clear(allow, r);
as->mrm.idx = (uint8_t)r;
}
noadd:
as->mrm.base = (uint8_t)ra_alloc1(as, ref, allow);
}
}
/* Fuse load into memory operand. */
static Reg asm_fuseload(ASMState *as, IRRef ref, RegSet allow)
{
IRIns *ir = IR(ref);
if (ra_hasreg(ir->r)) {
if (allow != RSET_EMPTY) { /* Fast path. */
ra_noweak(as, ir->r);
return ir->r;
}
fusespill:
/* Force a spill if only memory operands are allowed (asm_x87load). */
as->mrm.base = RID_ESP;
as->mrm.ofs = ra_spill(as, ir);
as->mrm.idx = RID_NONE;
return RID_MRM;
}
if (ir->o == IR_KNUM) {
RegSet avail = as->freeset & ~as->modset & RSET_FPR;
lua_assert(allow != RSET_EMPTY);
if (!(avail & (avail-1))) { /* Fuse if less than two regs available. */
as->mrm.ofs = ptr2addr(ir_knum(ir));
as->mrm.base = as->mrm.idx = RID_NONE;
return RID_MRM;
}
} else if (mayfuse(as, ref)) {
RegSet xallow = (allow & RSET_GPR) ? allow : RSET_GPR;
if (ir->o == IR_SLOAD) {
if (!(ir->op2 & (IRSLOAD_PARENT|IRSLOAD_CONVERT)) &&
noconflict(as, ref, IR_RETF, 0)) {
as->mrm.base = (uint8_t)ra_alloc1(as, REF_BASE, xallow);
as->mrm.ofs = 8*((int32_t)ir->op1-1) + ((ir->op2&IRSLOAD_FRAME)?4:0);
as->mrm.idx = RID_NONE;
return RID_MRM;
}
} else if (ir->o == IR_FLOAD) {
/* Generic fusion is only ok for 32 bit operand (but see asm_comp). */
if ((irt_isint(ir->t) || irt_isu32(ir->t) || irt_isaddr(ir->t)) &&
noconflict(as, ref, IR_FSTORE, 0)) {
asm_fusefref(as, ir, xallow);
return RID_MRM;
}
} else if (ir->o == IR_ALOAD || ir->o == IR_HLOAD || ir->o == IR_ULOAD) {
if (noconflict(as, ref, ir->o + IRDELTA_L2S, 0)) {
asm_fuseahuref(as, ir->op1, xallow);
return RID_MRM;
}
} else if (ir->o == IR_XLOAD) {
/* Generic fusion is not ok for 8/16 bit operands (but see asm_comp).
** Fusing unaligned memory operands is ok on x86 (except for SIMD types).
*/
if ((!irt_typerange(ir->t, IRT_I8, IRT_U16)) &&
noconflict(as, ref, IR_XSTORE, 0)) {
asm_fusexref(as, ir->op1, xallow);
return RID_MRM;
}
} else if (ir->o == IR_VLOAD) {
asm_fuseahuref(as, ir->op1, xallow);
return RID_MRM;
}
}
if (!(as->freeset & allow) &&
(allow == RSET_EMPTY || ra_hasspill(ir->s) || iscrossref(as, ref)))
goto fusespill;
return ra_allocref(as, ref, allow);
}
#if LJ_64
/* Don't fuse a 32 bit load into a 64 bit operation. */
static Reg asm_fuseloadm(ASMState *as, IRRef ref, RegSet allow, int is64)
{
if (is64 && !irt_is64(IR(ref)->t))
return ra_alloc1(as, ref, allow);
return asm_fuseload(as, ref, allow);
}
#else
#define asm_fuseloadm(as, ref, allow, is64) asm_fuseload(as, (ref), (allow))
#endif
/* -- Calls --------------------------------------------------------------- */
/* Count the required number of stack slots for a call. */
static int asm_count_call_slots(ASMState *as, const CCallInfo *ci, IRRef *args)
{
uint32_t i, nargs = CCI_NARGS(ci);
int nslots = 0;
#if LJ_64
if (LJ_ABI_WIN) {
nslots = (int)(nargs*2); /* Only matters for more than four args. */
} else {
int ngpr = REGARG_NUMGPR, nfpr = REGARG_NUMFPR;
for (i = 0; i < nargs; i++)
if (args[i] && irt_isfp(IR(args[i])->t)) {
if (nfpr > 0) nfpr--; else nslots += 2;
} else {
if (ngpr > 0) ngpr--; else nslots += 2;
}
}
#else
int ngpr = 0;
if ((ci->flags & CCI_CC_MASK) == CCI_CC_FASTCALL)
ngpr = 2;
else if ((ci->flags & CCI_CC_MASK) == CCI_CC_THISCALL)
ngpr = 1;
for (i = 0; i < nargs; i++)
if (args[i] && irt_isfp(IR(args[i])->t)) {
nslots += irt_isnum(IR(args[i])->t) ? 2 : 1;
} else {
if (ngpr > 0) ngpr--; else nslots++;
}
#endif
return nslots;
}
/* Generate a call to a C function. */
static void asm_gencall(ASMState *as, const CCallInfo *ci, IRRef *args)
{
uint32_t n, nargs = CCI_NARGS(ci);
int32_t ofs = STACKARG_OFS;
#if LJ_64
uint32_t gprs = REGARG_GPRS;
Reg fpr = REGARG_FIRSTFPR;
#if !LJ_ABI_WIN
MCode *patchnfpr = NULL;
#endif
#else
uint32_t gprs = 0;
if ((ci->flags & CCI_CC_MASK) != CCI_CC_CDECL) {
if ((ci->flags & CCI_CC_MASK) == CCI_CC_THISCALL)
gprs = (REGARG_GPRS & 31);
else if ((ci->flags & CCI_CC_MASK) == CCI_CC_FASTCALL)
gprs = REGARG_GPRS;
}
#endif
if ((void *)ci->func)
emit_call(as, ci->func);
#if LJ_64
if ((ci->flags & CCI_VARARG)) { /* Special handling for vararg calls. */
#if LJ_ABI_WIN
for (n = 0; n < 4 && n < nargs; n++) {
IRIns *ir = IR(args[n]);
if (irt_isfp(ir->t)) /* Duplicate FPRs in GPRs. */
emit_rr(as, XO_MOVDto, (irt_isnum(ir->t) ? REX_64 : 0) | (fpr+n),
((gprs >> (n*5)) & 31)); /* Either MOVD or MOVQ. */
}
#else
patchnfpr = --as->mcp; /* Indicate number of used FPRs in register al. */
*--as->mcp = XI_MOVrib | RID_EAX;
#endif
}
#endif
for (n = 0; n < nargs; n++) { /* Setup args. */
IRRef ref = args[n];
IRIns *ir = IR(ref);
Reg r;
#if LJ_64 && LJ_ABI_WIN
/* Windows/x64 argument registers are strictly positional. */
r = irt_isfp(ir->t) ? (fpr <= REGARG_LASTFPR ? fpr : 0) : (gprs & 31);
fpr++; gprs >>= 5;
#elif LJ_64
/* POSIX/x64 argument registers are used in order of appearance. */
if (irt_isfp(ir->t)) {
r = fpr <= REGARG_LASTFPR ? fpr++ : 0;
} else {
r = gprs & 31; gprs >>= 5;
}
#else
if (ref && irt_isfp(ir->t)) {
r = 0;
} else {
r = gprs & 31; gprs >>= 5;
if (!ref) continue;
}
#endif
if (r) { /* Argument is in a register. */
if (r < RID_MAX_GPR && ref < ASMREF_TMP1) {
#if LJ_64
if (ir->o == IR_KINT64)
emit_loadu64(as, r, ir_kint64(ir)->u64);
else
#endif
emit_loadi(as, r, ir->i);
} else {
lua_assert(rset_test(as->freeset, r)); /* Must have been evicted. */
if (ra_hasreg(ir->r)) {
ra_noweak(as, ir->r);
emit_movrr(as, ir, r, ir->r);
} else {
ra_allocref(as, ref, RID2RSET(r));
}
}
} else if (irt_isfp(ir->t)) { /* FP argument is on stack. */
lua_assert(!(irt_isfloat(ir->t) && irref_isk(ref))); /* No float k. */
if (LJ_32 && (ofs & 4) && irref_isk(ref)) {
/* Split stores for unaligned FP consts. */
emit_movmroi(as, RID_ESP, ofs, (int32_t)ir_knum(ir)->u32.lo);
emit_movmroi(as, RID_ESP, ofs+4, (int32_t)ir_knum(ir)->u32.hi);
} else {
r = ra_alloc1(as, ref, RSET_FPR);
emit_rmro(as, irt_isnum(ir->t) ? XO_MOVSDto : XO_MOVSSto,
r, RID_ESP, ofs);
}
ofs += (LJ_32 && irt_isfloat(ir->t)) ? 4 : 8;
} else { /* Non-FP argument is on stack. */
if (LJ_32 && ref < ASMREF_TMP1) {
emit_movmroi(as, RID_ESP, ofs, ir->i);
} else {
r = ra_alloc1(as, ref, RSET_GPR);
emit_movtomro(as, REX_64 + r, RID_ESP, ofs);
}
ofs += sizeof(intptr_t);
}
checkmclim(as);
}
#if LJ_64 && !LJ_ABI_WIN
if (patchnfpr) *patchnfpr = fpr - REGARG_FIRSTFPR;
#endif
}
/* Setup result reg/sp for call. Evict scratch regs. */
static void asm_setupresult(ASMState *as, IRIns *ir, const CCallInfo *ci)
{
RegSet drop = RSET_SCRATCH;
int hiop = (LJ_32 && (ir+1)->o == IR_HIOP);
if ((ci->flags & CCI_NOFPRCLOBBER))
drop &= ~RSET_FPR;
if (ra_hasreg(ir->r))
rset_clear(drop, ir->r); /* Dest reg handled below. */
if (hiop && ra_hasreg((ir+1)->r))
rset_clear(drop, (ir+1)->r); /* Dest reg handled below. */
ra_evictset(as, drop); /* Evictions must be performed first. */
if (ra_used(ir)) {
if (irt_isfp(ir->t)) {
int32_t ofs = sps_scale(ir->s); /* Use spill slot or temp slots. */
#if LJ_64
if ((ci->flags & CCI_CASTU64)) {
Reg dest = ir->r;
if (ra_hasreg(dest)) {
ra_free(as, dest);
ra_modified(as, dest);
emit_rr(as, XO_MOVD, dest|REX_64, RID_RET); /* Really MOVQ. */
}
if (ofs) emit_movtomro(as, RID_RET|REX_64, RID_ESP, ofs);
} else {
ra_destreg(as, ir, RID_FPRET);
}
#else
/* Number result is in x87 st0 for x86 calling convention. */
Reg dest = ir->r;
if (ra_hasreg(dest)) {
ra_free(as, dest);
ra_modified(as, dest);
emit_rmro(as, irt_isnum(ir->t) ? XMM_MOVRM(as) : XO_MOVSS,
dest, RID_ESP, ofs);
}
if ((ci->flags & CCI_CASTU64)) {
emit_movtomro(as, RID_RETLO, RID_ESP, ofs);
emit_movtomro(as, RID_RETHI, RID_ESP, ofs+4);
} else {
emit_rmro(as, irt_isnum(ir->t) ? XO_FSTPq : XO_FSTPd,
irt_isnum(ir->t) ? XOg_FSTPq : XOg_FSTPd, RID_ESP, ofs);
}
#endif
#if LJ_32
} else if (hiop) {
ra_destpair(as, ir);
#endif
} else {
lua_assert(!irt_ispri(ir->t));
ra_destreg(as, ir, RID_RET);
}
} else if (LJ_32 && irt_isfp(ir->t)) {
emit_x87op(as, XI_FPOP); /* Pop unused result from x87 st0. */
}
}
static void asm_call(ASMState *as, IRIns *ir)
{
IRRef args[CCI_NARGS_MAX];
const CCallInfo *ci = &lj_ir_callinfo[ir->op2];
asm_collectargs(as, ir, ci, args);
asm_setupresult(as, ir, ci);
asm_gencall(as, ci, args);
}
/* Return a constant function pointer or NULL for indirect calls. */
static void *asm_callx_func(ASMState *as, IRIns *irf, IRRef func)
{
#if LJ_32
UNUSED(as);
if (irref_isk(func))
return (void *)irf->i;
#else
if (irref_isk(func)) {
MCode *p;
if (irf->o == IR_KINT64)
p = (MCode *)(void *)ir_k64(irf)->u64;
else
p = (MCode *)(void *)(uintptr_t)(uint32_t)irf->i;
if (p - as->mcp == (int32_t)(p - as->mcp))
return p; /* Call target is still in +-2GB range. */
/* Avoid the indirect case of emit_call(). Try to hoist func addr. */
}
#endif
return NULL;
}
static void asm_callx(ASMState *as, IRIns *ir)
{
IRRef args[CCI_NARGS_MAX*2];
CCallInfo ci;
IRRef func;
IRIns *irf;
int32_t spadj = 0;
ci.flags = asm_callx_flags(as, ir);
asm_collectargs(as, ir, &ci, args);
asm_setupresult(as, ir, &ci);
#if LJ_32
/* Have to readjust stack after non-cdecl calls due to callee cleanup. */
if ((ci.flags & CCI_CC_MASK) != CCI_CC_CDECL)
spadj = 4 * asm_count_call_slots(as, &ci, args);
#endif
func = ir->op2; irf = IR(func);
if (irf->o == IR_CARG) { func = irf->op1; irf = IR(func); }
ci.func = (ASMFunction)asm_callx_func(as, irf, func);
if (!(void *)ci.func) {
/* Use a (hoistable) non-scratch register for indirect calls. */
RegSet allow = (RSET_GPR & ~RSET_SCRATCH);
Reg r = ra_alloc1(as, func, allow);
if (LJ_32) emit_spsub(as, spadj); /* Above code may cause restores! */
emit_rr(as, XO_GROUP5, XOg_CALL, r);
} else if (LJ_32) {
emit_spsub(as, spadj);
}
asm_gencall(as, &ci, args);
}
/* -- Returns ------------------------------------------------------------- */
/* Return to lower frame. Guard that it goes to the right spot. */
static void asm_retf(ASMState *as, IRIns *ir)
{
Reg base = ra_alloc1(as, REF_BASE, RSET_GPR);
void *pc = ir_kptr(IR(ir->op2));
int32_t delta = 1+bc_a(*((const BCIns *)pc - 1));
as->topslot -= (BCReg)delta;
if ((int32_t)as->topslot < 0) as->topslot = 0;
emit_setgl(as, base, jit_base);
emit_addptr(as, base, -8*delta);
asm_guardcc(as, CC_NE);
emit_gmroi(as, XG_ARITHi(XOg_CMP), base, -4, ptr2addr(pc));
}
/* -- Type conversions ---------------------------------------------------- */
static void asm_tointg(ASMState *as, IRIns *ir, Reg left)
{
Reg tmp = ra_scratch(as, rset_exclude(RSET_FPR, left));
Reg dest = ra_dest(as, ir, RSET_GPR);
asm_guardcc(as, CC_P);
asm_guardcc(as, CC_NE);
emit_rr(as, XO_UCOMISD, left, tmp);
emit_rr(as, XO_CVTSI2SD, tmp, dest);
if (!(as->flags & JIT_F_SPLIT_XMM))
emit_rr(as, XO_XORPS, tmp, tmp); /* Avoid partial register stall. */
emit_rr(as, XO_CVTTSD2SI, dest, left);
/* Can't fuse since left is needed twice. */
}
static void asm_tobit(ASMState *as, IRIns *ir)
{
Reg dest = ra_dest(as, ir, RSET_GPR);
Reg tmp = ra_noreg(IR(ir->op1)->r) ?
ra_alloc1(as, ir->op1, RSET_FPR) :
ra_scratch(as, RSET_FPR);
Reg right = asm_fuseload(as, ir->op2, rset_exclude(RSET_FPR, tmp));
emit_rr(as, XO_MOVDto, tmp, dest);
emit_mrm(as, XO_ADDSD, tmp, right);
ra_left(as, tmp, ir->op1);
}
static void asm_conv(ASMState *as, IRIns *ir)
{
IRType st = (IRType)(ir->op2 & IRCONV_SRCMASK);
int st64 = (st == IRT_I64 || st == IRT_U64 || (LJ_64 && st == IRT_P64));
int stfp = (st == IRT_NUM || st == IRT_FLOAT);
IRRef lref = ir->op1;
lua_assert(irt_type(ir->t) != st);
lua_assert(!(LJ_32 && (irt_isint64(ir->t) || st64))); /* Handled by SPLIT. */
if (irt_isfp(ir->t)) {
Reg dest = ra_dest(as, ir, RSET_FPR);
if (stfp) { /* FP to FP conversion. */
Reg left = asm_fuseload(as, lref, RSET_FPR);
emit_mrm(as, st == IRT_NUM ? XO_CVTSD2SS : XO_CVTSS2SD, dest, left);
if (left == dest) return; /* Avoid the XO_XORPS. */
} else if (LJ_32 && st == IRT_U32) { /* U32 to FP conversion on x86. */
/* number = (2^52+2^51 .. u32) - (2^52+2^51) */
cTValue *k = lj_ir_k64_find(as->J, U64x(43380000,00000000));
Reg bias = ra_scratch(as, rset_exclude(RSET_FPR, dest));
if (irt_isfloat(ir->t))
emit_rr(as, XO_CVTSD2SS, dest, dest);
emit_rr(as, XO_SUBSD, dest, bias); /* Subtract 2^52+2^51 bias. */
emit_rr(as, XO_XORPS, dest, bias); /* Merge bias and integer. */
emit_loadn(as, bias, k);
emit_mrm(as, XO_MOVD, dest, asm_fuseload(as, lref, RSET_GPR));
return;
} else { /* Integer to FP conversion. */
Reg left = (LJ_64 && (st == IRT_U32 || st == IRT_U64)) ?
ra_alloc1(as, lref, RSET_GPR) :
asm_fuseloadm(as, lref, RSET_GPR, st64);
if (LJ_64 && st == IRT_U64) {
MCLabel l_end = emit_label(as);
const void *k = lj_ir_k64_find(as->J, U64x(43f00000,00000000));
emit_rma(as, XO_ADDSD, dest, k); /* Add 2^64 to compensate. */
emit_sjcc(as, CC_NS, l_end);
emit_rr(as, XO_TEST, left|REX_64, left); /* Check if u64 >= 2^63. */
}
emit_mrm(as, irt_isnum(ir->t) ? XO_CVTSI2SD : XO_CVTSI2SS,
dest|((LJ_64 && (st64 || st == IRT_U32)) ? REX_64 : 0), left);
}
if (!(as->flags & JIT_F_SPLIT_XMM))
emit_rr(as, XO_XORPS, dest, dest); /* Avoid partial register stall. */
} else if (stfp) { /* FP to integer conversion. */
if (irt_isguard(ir->t)) {
/* Checked conversions are only supported from number to int. */
lua_assert(irt_isint(ir->t) && st == IRT_NUM);
asm_tointg(as, ir, ra_alloc1(as, lref, RSET_FPR));
} else {
Reg dest = ra_dest(as, ir, RSET_GPR);
x86Op op = st == IRT_NUM ?
((ir->op2 & IRCONV_TRUNC) ? XO_CVTTSD2SI : XO_CVTSD2SI) :
((ir->op2 & IRCONV_TRUNC) ? XO_CVTTSS2SI : XO_CVTSS2SI);
if (LJ_64 ? irt_isu64(ir->t) : irt_isu32(ir->t)) {
/* LJ_64: For inputs >= 2^63 add -2^64, convert again. */
/* LJ_32: For inputs >= 2^31 add -2^31, convert again and add 2^31. */
Reg tmp = ra_noreg(IR(lref)->r) ? ra_alloc1(as, lref, RSET_FPR) :
ra_scratch(as, RSET_FPR);
MCLabel l_end = emit_label(as);
if (LJ_32)
emit_gri(as, XG_ARITHi(XOg_ADD), dest, (int32_t)0x80000000);
emit_rr(as, op, dest|REX_64, tmp);
if (st == IRT_NUM)
emit_rma(as, XO_ADDSD, tmp, lj_ir_k64_find(as->J,
LJ_64 ? U64x(c3f00000,00000000) : U64x(c1e00000,00000000)));
else
emit_rma(as, XO_ADDSS, tmp, lj_ir_k64_find(as->J,
LJ_64 ? U64x(00000000,df800000) : U64x(00000000,cf000000)));
emit_sjcc(as, CC_NS, l_end);
emit_rr(as, XO_TEST, dest|REX_64, dest); /* Check if dest negative. */
emit_rr(as, op, dest|REX_64, tmp);
ra_left(as, tmp, lref);
} else {
Reg left = asm_fuseload(as, lref, RSET_FPR);
if (LJ_64 && irt_isu32(ir->t))
emit_rr(as, XO_MOV, dest, dest); /* Zero hiword. */
emit_mrm(as, op,
dest|((LJ_64 &&
(irt_is64(ir->t) || irt_isu32(ir->t))) ? REX_64 : 0),
left);
}
}
} else if (st >= IRT_I8 && st <= IRT_U16) { /* Extend to 32 bit integer. */
Reg left, dest = ra_dest(as, ir, RSET_GPR);
RegSet allow = RSET_GPR;
x86Op op;
lua_assert(irt_isint(ir->t) || irt_isu32(ir->t));
if (st == IRT_I8) {
op = XO_MOVSXb; allow = RSET_GPR8; dest |= FORCE_REX;
} else if (st == IRT_U8) {
op = XO_MOVZXb; allow = RSET_GPR8; dest |= FORCE_REX;
} else if (st == IRT_I16) {
op = XO_MOVSXw;
} else {
op = XO_MOVZXw;
}
left = asm_fuseload(as, lref, allow);
/* Add extra MOV if source is already in wrong register. */
if (!LJ_64 && left != RID_MRM && !rset_test(allow, left)) {
Reg tmp = ra_scratch(as, allow);
emit_rr(as, op, dest, tmp);
emit_rr(as, XO_MOV, tmp, left);
} else {
emit_mrm(as, op, dest, left);
}
} else { /* 32/64 bit integer conversions. */
if (LJ_32) { /* Only need to handle 32/32 bit no-op (cast) on x86. */
Reg dest = ra_dest(as, ir, RSET_GPR);
ra_left(as, dest, lref); /* Do nothing, but may need to move regs. */
} else if (irt_is64(ir->t)) {
Reg dest = ra_dest(as, ir, RSET_GPR);
if (st64 || !(ir->op2 & IRCONV_SEXT)) {
/* 64/64 bit no-op (cast) or 32 to 64 bit zero extension. */
ra_left(as, dest, lref); /* Do nothing, but may need to move regs. */
} else { /* 32 to 64 bit sign extension. */
Reg left = asm_fuseload(as, lref, RSET_GPR);
emit_mrm(as, XO_MOVSXd, dest|REX_64, left);
}
} else {
Reg dest = ra_dest(as, ir, RSET_GPR);
if (st64) {
Reg left = asm_fuseload(as, lref, RSET_GPR);
/* This is either a 32 bit reg/reg mov which zeroes the hiword
** or a load of the loword from a 64 bit address.
*/
emit_mrm(as, XO_MOV, dest, left);
} else { /* 32/32 bit no-op (cast). */
ra_left(as, dest, lref); /* Do nothing, but may need to move regs. */
}
}
}
}
#if LJ_32 && LJ_HASFFI
/* No SSE conversions to/from 64 bit on x86, so resort to ugly x87 code. */
/* 64 bit integer to FP conversion in 32 bit mode. */
static void asm_conv_fp_int64(ASMState *as, IRIns *ir)
{
Reg hi = ra_alloc1(as, ir->op1, RSET_GPR);
Reg lo = ra_alloc1(as, (ir-1)->op1, rset_exclude(RSET_GPR, hi));
int32_t ofs = sps_scale(ir->s); /* Use spill slot or temp slots. */
Reg dest = ir->r;
if (ra_hasreg(dest)) {
ra_free(as, dest);
ra_modified(as, dest);
emit_rmro(as, irt_isnum(ir->t) ? XMM_MOVRM(as) : XO_MOVSS,
dest, RID_ESP, ofs);
}
emit_rmro(as, irt_isnum(ir->t) ? XO_FSTPq : XO_FSTPd,
irt_isnum(ir->t) ? XOg_FSTPq : XOg_FSTPd, RID_ESP, ofs);
if (((ir-1)->op2 & IRCONV_SRCMASK) == IRT_U64) {
/* For inputs in [2^63,2^64-1] add 2^64 to compensate. */
MCLabel l_end = emit_label(as);
emit_rma(as, XO_FADDq, XOg_FADDq,
lj_ir_k64_find(as->J, U64x(43f00000,00000000)));
emit_sjcc(as, CC_NS, l_end);
emit_rr(as, XO_TEST, hi, hi); /* Check if u64 >= 2^63. */
} else {
lua_assert(((ir-1)->op2 & IRCONV_SRCMASK) == IRT_I64);
}
emit_rmro(as, XO_FILDq, XOg_FILDq, RID_ESP, 0);
/* NYI: Avoid narrow-to-wide store-to-load forwarding stall. */
emit_rmro(as, XO_MOVto, hi, RID_ESP, 4);
emit_rmro(as, XO_MOVto, lo, RID_ESP, 0);
}
/* FP to 64 bit integer conversion in 32 bit mode. */
static void asm_conv_int64_fp(ASMState *as, IRIns *ir)
{
IRType st = (IRType)((ir-1)->op2 & IRCONV_SRCMASK);
IRType dt = (((ir-1)->op2 & IRCONV_DSTMASK) >> IRCONV_DSH);
Reg lo, hi;
lua_assert(st == IRT_NUM || st == IRT_FLOAT);
lua_assert(dt == IRT_I64 || dt == IRT_U64);
lua_assert(((ir-1)->op2 & IRCONV_TRUNC));
hi = ra_dest(as, ir, RSET_GPR);
lo = ra_dest(as, ir-1, rset_exclude(RSET_GPR, hi));
if (ra_used(ir-1)) emit_rmro(as, XO_MOV, lo, RID_ESP, 0);
/* NYI: Avoid wide-to-narrow store-to-load forwarding stall. */
if (!(as->flags & JIT_F_SSE3)) { /* Set FPU rounding mode to default. */
emit_rmro(as, XO_FLDCW, XOg_FLDCW, RID_ESP, 4);
emit_rmro(as, XO_MOVto, lo, RID_ESP, 4);
emit_gri(as, XG_ARITHi(XOg_AND), lo, 0xf3ff);
}
if (dt == IRT_U64) {
/* For inputs in [2^63,2^64-1] add -2^64 and convert again. */
MCLabel l_pop, l_end = emit_label(as);
emit_x87op(as, XI_FPOP);
l_pop = emit_label(as);
emit_sjmp(as, l_end);
emit_rmro(as, XO_MOV, hi, RID_ESP, 4);
if ((as->flags & JIT_F_SSE3))
emit_rmro(as, XO_FISTTPq, XOg_FISTTPq, RID_ESP, 0);
else
emit_rmro(as, XO_FISTPq, XOg_FISTPq, RID_ESP, 0);
emit_rma(as, XO_FADDq, XOg_FADDq,
lj_ir_k64_find(as->J, U64x(c3f00000,00000000)));
emit_sjcc(as, CC_NS, l_pop);
emit_rr(as, XO_TEST, hi, hi); /* Check if out-of-range (2^63). */
}
emit_rmro(as, XO_MOV, hi, RID_ESP, 4);
if ((as->flags & JIT_F_SSE3)) { /* Truncation is easy with SSE3. */
emit_rmro(as, XO_FISTTPq, XOg_FISTTPq, RID_ESP, 0);
} else { /* Otherwise set FPU rounding mode to truncate before the store. */
emit_rmro(as, XO_FISTPq, XOg_FISTPq, RID_ESP, 0);
emit_rmro(as, XO_FLDCW, XOg_FLDCW, RID_ESP, 0);
emit_rmro(as, XO_MOVtow, lo, RID_ESP, 0);
emit_rmro(as, XO_ARITHw(XOg_OR), lo, RID_ESP, 0);
emit_loadi(as, lo, 0xc00);
emit_rmro(as, XO_FNSTCW, XOg_FNSTCW, RID_ESP, 0);
}
if (dt == IRT_U64)
emit_x87op(as, XI_FDUP);
emit_mrm(as, st == IRT_NUM ? XO_FLDq : XO_FLDd,
st == IRT_NUM ? XOg_FLDq: XOg_FLDd,
asm_fuseload(as, ir->op1, RSET_EMPTY));
}
#endif
static void asm_strto(ASMState *as, IRIns *ir)
{
/* Force a spill slot for the destination register (if any). */
const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_strscan_num];
IRRef args[2];
RegSet drop = RSET_SCRATCH;
if ((drop & RSET_FPR) != RSET_FPR && ra_hasreg(ir->r))
rset_set(drop, ir->r); /* WIN64 doesn't spill all FPRs. */
ra_evictset(as, drop);
asm_guardcc(as, CC_E);
emit_rr(as, XO_TEST, RID_RET, RID_RET); /* Test return status. */
args[0] = ir->op1; /* GCstr *str */
args[1] = ASMREF_TMP1; /* TValue *n */
asm_gencall(as, ci, args);
/* Store the result to the spill slot or temp slots. */
emit_rmro(as, XO_LEA, ra_releasetmp(as, ASMREF_TMP1)|REX_64,
RID_ESP, sps_scale(ir->s));
}
static void asm_tostr(ASMState *as, IRIns *ir)
{
IRIns *irl = IR(ir->op1);
IRRef args[2];
args[0] = ASMREF_L;
as->gcsteps++;
if (irt_isnum(irl->t)) {
const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_str_fromnum];
args[1] = ASMREF_TMP1; /* const lua_Number * */
asm_setupresult(as, ir, ci); /* GCstr * */
asm_gencall(as, ci, args);
emit_rmro(as, XO_LEA, ra_releasetmp(as, ASMREF_TMP1)|REX_64,
RID_ESP, ra_spill(as, irl));
} else {
const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_str_fromint];
args[1] = ir->op1; /* int32_t k */
asm_setupresult(as, ir, ci); /* GCstr * */
asm_gencall(as, ci, args);
}
}
/* -- Memory references --------------------------------------------------- */
static void asm_aref(ASMState *as, IRIns *ir)
{
Reg dest = ra_dest(as, ir, RSET_GPR);
asm_fusearef(as, ir, RSET_GPR);
if (!(as->mrm.idx == RID_NONE && as->mrm.ofs == 0))
emit_mrm(as, XO_LEA, dest, RID_MRM);
else if (as->mrm.base != dest)
emit_rr(as, XO_MOV, dest, as->mrm.base);
}
/* Merge NE(HREF, niltv) check. */
static MCode *merge_href_niltv(ASMState *as, IRIns *ir)
{
/* Assumes nothing else generates NE of HREF. */
if ((ir[1].o == IR_NE || ir[1].o == IR_EQ) && ir[1].op1 == as->curins &&
ra_hasreg(ir->r)) {
MCode *p = as->mcp;
p += (LJ_64 && *p != XI_ARITHi) ? 7+6 : 6+6;
/* Ensure no loop branch inversion happened. */
if (p[-6] == 0x0f && p[-5] == XI_JCCn+(CC_NE^(ir[1].o & 1))) {
as->mcp = p; /* Kill cmp reg, imm32 + jz exit. */
return p + *(int32_t *)(p-4); /* Return exit address. */
}
}
return NULL;
}
/* Inlined hash lookup. Specialized for key type and for const keys.
** The equivalent C code is:
** Node *n = hashkey(t, key);
** do {
** if (lj_obj_equal(&n->key, key)) return &n->val;
** } while ((n = nextnode(n)));
** return niltv(L);
*/
static void asm_href(ASMState *as, IRIns *ir)
{
MCode *nilexit = merge_href_niltv(as, ir); /* Do this before any restores. */
RegSet allow = RSET_GPR;
Reg dest = ra_dest(as, ir, allow);
Reg tab = ra_alloc1(as, ir->op1, rset_clear(allow, dest));
Reg key = RID_NONE, tmp = RID_NONE;
IRIns *irkey = IR(ir->op2);
int isk = irref_isk(ir->op2);
IRType1 kt = irkey->t;
uint32_t khash;
MCLabel l_end, l_loop, l_next;
if (!isk) {
rset_clear(allow, tab);
key = ra_alloc1(as, ir->op2, irt_isnum(kt) ? RSET_FPR : allow);
if (!irt_isstr(kt))
tmp = ra_scratch(as, rset_exclude(allow, key));
}
/* Key not found in chain: jump to exit (if merged with NE) or load niltv. */
l_end = emit_label(as);
if (nilexit && ir[1].o == IR_NE) {
emit_jcc(as, CC_E, nilexit); /* XI_JMP is not found by lj_asm_patchexit. */
nilexit = NULL;
} else {
emit_loada(as, dest, niltvg(J2G(as->J)));
}
/* Follow hash chain until the end. */
l_loop = emit_sjcc_label(as, CC_NZ);
emit_rr(as, XO_TEST, dest, dest);
emit_rmro(as, XO_MOV, dest, dest, offsetof(Node, next));
l_next = emit_label(as);
/* Type and value comparison. */
if (nilexit)
emit_jcc(as, CC_E, nilexit);
else
emit_sjcc(as, CC_E, l_end);
if (irt_isnum(kt)) {
if (isk) {
/* Assumes -0.0 is already canonicalized to +0.0. */
emit_gmroi(as, XG_ARITHi(XOg_CMP), dest, offsetof(Node, key.u32.lo),
(int32_t)ir_knum(irkey)->u32.lo);
emit_sjcc(as, CC_NE, l_next);
emit_gmroi(as, XG_ARITHi(XOg_CMP), dest, offsetof(Node, key.u32.hi),
(int32_t)ir_knum(irkey)->u32.hi);
} else {
emit_sjcc(as, CC_P, l_next);
emit_rmro(as, XO_UCOMISD, key, dest, offsetof(Node, key.n));
emit_sjcc(as, CC_AE, l_next);
/* The type check avoids NaN penalties and complaints from Valgrind. */
#if LJ_64
emit_u32(as, LJ_TISNUM);
emit_rmro(as, XO_ARITHi, XOg_CMP, dest, offsetof(Node, key.it));
#else
emit_i8(as, LJ_TISNUM);
emit_rmro(as, XO_ARITHi8, XOg_CMP, dest, offsetof(Node, key.it));
#endif
}
#if LJ_64
} else if (irt_islightud(kt)) {
emit_rmro(as, XO_CMP, key|REX_64, dest, offsetof(Node, key.u64));
#endif
} else {
if (!irt_ispri(kt)) {
lua_assert(irt_isaddr(kt));
if (isk)
emit_gmroi(as, XG_ARITHi(XOg_CMP), dest, offsetof(Node, key.gcr),
ptr2addr(ir_kgc(irkey)));
else
emit_rmro(as, XO_CMP, key, dest, offsetof(Node, key.gcr));
emit_sjcc(as, CC_NE, l_next);
}
lua_assert(!irt_isnil(kt));
emit_i8(as, irt_toitype(kt));
emit_rmro(as, XO_ARITHi8, XOg_CMP, dest, offsetof(Node, key.it));
}
emit_sfixup(as, l_loop);
checkmclim(as);
/* Load main position relative to tab->node into dest. */
khash = isk ? ir_khash(irkey) : 1;
if (khash == 0) {
emit_rmro(as, XO_MOV, dest, tab, offsetof(GCtab, node));
} else {
emit_rmro(as, XO_ARITH(XOg_ADD), dest, tab, offsetof(GCtab, node));
if ((as->flags & JIT_F_PREFER_IMUL)) {
emit_i8(as, sizeof(Node));
emit_rr(as, XO_IMULi8, dest, dest);
} else {
emit_shifti(as, XOg_SHL, dest, 3);
emit_rmrxo(as, XO_LEA, dest, dest, dest, XM_SCALE2, 0);
}
if (isk) {
emit_gri(as, XG_ARITHi(XOg_AND), dest, (int32_t)khash);
emit_rmro(as, XO_MOV, dest, tab, offsetof(GCtab, hmask));
} else if (irt_isstr(kt)) {
emit_rmro(as, XO_ARITH(XOg_AND), dest, key, offsetof(GCstr, hash));
emit_rmro(as, XO_MOV, dest, tab, offsetof(GCtab, hmask));
} else { /* Must match with hashrot() in lj_tab.c. */
emit_rmro(as, XO_ARITH(XOg_AND), dest, tab, offsetof(GCtab, hmask));
emit_rr(as, XO_ARITH(XOg_SUB), dest, tmp);
emit_shifti(as, XOg_ROL, tmp, HASH_ROT3);
emit_rr(as, XO_ARITH(XOg_XOR), dest, tmp);
emit_shifti(as, XOg_ROL, dest, HASH_ROT2);
emit_rr(as, XO_ARITH(XOg_SUB), tmp, dest);
emit_shifti(as, XOg_ROL, dest, HASH_ROT1);
emit_rr(as, XO_ARITH(XOg_XOR), tmp, dest);
if (irt_isnum(kt)) {
emit_rr(as, XO_ARITH(XOg_ADD), dest, dest);
#if LJ_64
emit_shifti(as, XOg_SHR|REX_64, dest, 32);
emit_rr(as, XO_MOV, tmp, dest);
emit_rr(as, XO_MOVDto, key|REX_64, dest);
#else
emit_rmro(as, XO_MOV, dest, RID_ESP, ra_spill(as, irkey)+4);
emit_rr(as, XO_MOVDto, key, tmp);
#endif
} else {
emit_rr(as, XO_MOV, tmp, key);
emit_rmro(as, XO_LEA, dest, key, HASH_BIAS);
}
}
}
}
static void asm_hrefk(ASMState *as, IRIns *ir)
{
IRIns *kslot = IR(ir->op2);
IRIns *irkey = IR(kslot->op1);
int32_t ofs = (int32_t)(kslot->op2 * sizeof(Node));
Reg dest = ra_used(ir) ? ra_dest(as, ir, RSET_GPR) : RID_NONE;
Reg node = ra_alloc1(as, ir->op1, RSET_GPR);
#if !LJ_64
MCLabel l_exit;
#endif
lua_assert(ofs % sizeof(Node) == 0);
if (ra_hasreg(dest)) {
if (ofs != 0) {
if (dest == node && !(as->flags & JIT_F_LEA_AGU))
emit_gri(as, XG_ARITHi(XOg_ADD), dest, ofs);
else
emit_rmro(as, XO_LEA, dest, node, ofs);
} else if (dest != node) {
emit_rr(as, XO_MOV, dest, node);
}
}
asm_guardcc(as, CC_NE);
#if LJ_64
if (!irt_ispri(irkey->t)) {
Reg key = ra_scratch(as, rset_exclude(RSET_GPR, node));
emit_rmro(as, XO_CMP, key|REX_64, node,
ofs + (int32_t)offsetof(Node, key.u64));
lua_assert(irt_isnum(irkey->t) || irt_isgcv(irkey->t));
/* Assumes -0.0 is already canonicalized to +0.0. */
emit_loadu64(as, key, irt_isnum(irkey->t) ? ir_knum(irkey)->u64 :
((uint64_t)irt_toitype(irkey->t) << 32) |
(uint64_t)(uint32_t)ptr2addr(ir_kgc(irkey)));
} else {
lua_assert(!irt_isnil(irkey->t));
emit_i8(as, irt_toitype(irkey->t));
emit_rmro(as, XO_ARITHi8, XOg_CMP, node,
ofs + (int32_t)offsetof(Node, key.it));
}
#else
l_exit = emit_label(as);
if (irt_isnum(irkey->t)) {
/* Assumes -0.0 is already canonicalized to +0.0. */
emit_gmroi(as, XG_ARITHi(XOg_CMP), node,
ofs + (int32_t)offsetof(Node, key.u32.lo),
(int32_t)ir_knum(irkey)->u32.lo);
emit_sjcc(as, CC_NE, l_exit);
emit_gmroi(as, XG_ARITHi(XOg_CMP), node,
ofs + (int32_t)offsetof(Node, key.u32.hi),
(int32_t)ir_knum(irkey)->u32.hi);
} else {
if (!irt_ispri(irkey->t)) {
lua_assert(irt_isgcv(irkey->t));
emit_gmroi(as, XG_ARITHi(XOg_CMP), node,
ofs + (int32_t)offsetof(Node, key.gcr),
ptr2addr(ir_kgc(irkey)));
emit_sjcc(as, CC_NE, l_exit);
}
lua_assert(!irt_isnil(irkey->t));
emit_i8(as, irt_toitype(irkey->t));
emit_rmro(as, XO_ARITHi8, XOg_CMP, node,
ofs + (int32_t)offsetof(Node, key.it));
}
#endif
}
static void asm_newref(ASMState *as, IRIns *ir)
{
const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_tab_newkey];
IRRef args[3];
IRIns *irkey;
Reg tmp;
if (ir->r == RID_SINK)
return;
args[0] = ASMREF_L; /* lua_State *L */
args[1] = ir->op1; /* GCtab *t */
args[2] = ASMREF_TMP1; /* cTValue *key */
asm_setupresult(as, ir, ci); /* TValue * */
asm_gencall(as, ci, args);
tmp = ra_releasetmp(as, ASMREF_TMP1);
irkey = IR(ir->op2);
if (irt_isnum(irkey->t)) {
/* For numbers use the constant itself or a spill slot as a TValue. */
if (irref_isk(ir->op2))
emit_loada(as, tmp, ir_knum(irkey));
else
emit_rmro(as, XO_LEA, tmp|REX_64, RID_ESP, ra_spill(as, irkey));
} else {
/* Otherwise use g->tmptv to hold the TValue. */
if (!irref_isk(ir->op2)) {
Reg src = ra_alloc1(as, ir->op2, rset_exclude(RSET_GPR, tmp));
emit_movtomro(as, REX_64IR(irkey, src), tmp, 0);
} else if (!irt_ispri(irkey->t)) {
emit_movmroi(as, tmp, 0, irkey->i);
}
if (!(LJ_64 && irt_islightud(irkey->t)))
emit_movmroi(as, tmp, 4, irt_toitype(irkey->t));
emit_loada(as, tmp, &J2G(as->J)->tmptv);
}
}
static void asm_uref(ASMState *as, IRIns *ir)
{
/* NYI: Check that UREFO is still open and not aliasing a slot. */
Reg dest = ra_dest(as, ir, RSET_GPR);
if (irref_isk(ir->op1)) {
GCfunc *fn = ir_kfunc(IR(ir->op1));
MRef *v = &gcref(fn->l.uvptr[(ir->op2 >> 8)])->uv.v;
emit_rma(as, XO_MOV, dest, v);
} else {
Reg uv = ra_scratch(as, RSET_GPR);
Reg func = ra_alloc1(as, ir->op1, RSET_GPR);
if (ir->o == IR_UREFC) {
emit_rmro(as, XO_LEA, dest, uv, offsetof(GCupval, tv));
asm_guardcc(as, CC_NE);
emit_i8(as, 1);
emit_rmro(as, XO_ARITHib, XOg_CMP, uv, offsetof(GCupval, closed));
} else {
emit_rmro(as, XO_MOV, dest, uv, offsetof(GCupval, v));
}
emit_rmro(as, XO_MOV, uv, func,
(int32_t)offsetof(GCfuncL, uvptr) + 4*(int32_t)(ir->op2 >> 8));
}
}
static void asm_fref(ASMState *as, IRIns *ir)
{
Reg dest = ra_dest(as, ir, RSET_GPR);
asm_fusefref(as, ir, RSET_GPR);
emit_mrm(as, XO_LEA, dest, RID_MRM);
}
static void asm_strref(ASMState *as, IRIns *ir)
{
Reg dest = ra_dest(as, ir, RSET_GPR);
asm_fusestrref(as, ir, RSET_GPR);
if (as->mrm.base == RID_NONE)
emit_loadi(as, dest, as->mrm.ofs);
else if (as->mrm.base == dest && as->mrm.idx == RID_NONE)
emit_gri(as, XG_ARITHi(XOg_ADD), dest, as->mrm.ofs);
else
emit_mrm(as, XO_LEA, dest, RID_MRM);
}
/* -- Loads and stores ---------------------------------------------------- */
static void asm_fxload(ASMState *as, IRIns *ir)
{
Reg dest = ra_dest(as, ir, irt_isfp(ir->t) ? RSET_FPR : RSET_GPR);
x86Op xo;
if (ir->o == IR_FLOAD)
asm_fusefref(as, ir, RSET_GPR);
else
asm_fusexref(as, ir->op1, RSET_GPR);
/* ir->op2 is ignored -- unaligned loads are ok on x86. */
switch (irt_type(ir->t)) {
case IRT_I8: xo = XO_MOVSXb; break;
case IRT_U8: xo = XO_MOVZXb; break;
case IRT_I16: xo = XO_MOVSXw; break;
case IRT_U16: xo = XO_MOVZXw; break;
case IRT_NUM: xo = XMM_MOVRM(as); break;
case IRT_FLOAT: xo = XO_MOVSS; break;
default:
if (LJ_64 && irt_is64(ir->t))
dest |= REX_64;
else
lua_assert(irt_isint(ir->t) || irt_isu32(ir->t) || irt_isaddr(ir->t));
xo = XO_MOV;
break;
}
emit_mrm(as, xo, dest, RID_MRM);
}
static void asm_fxstore(ASMState *as, IRIns *ir)
{
RegSet allow = RSET_GPR;
Reg src = RID_NONE, osrc = RID_NONE;
int32_t k = 0;
if (ir->r == RID_SINK)
return;
/* The IRT_I16/IRT_U16 stores should never be simplified for constant
** values since mov word [mem], imm16 has a length-changing prefix.
*/
if (irt_isi16(ir->t) || irt_isu16(ir->t) || irt_isfp(ir->t) ||
!asm_isk32(as, ir->op2, &k)) {
RegSet allow8 = irt_isfp(ir->t) ? RSET_FPR :
(irt_isi8(ir->t) || irt_isu8(ir->t)) ? RSET_GPR8 : RSET_GPR;
src = osrc = ra_alloc1(as, ir->op2, allow8);
if (!LJ_64 && !rset_test(allow8, src)) { /* Already in wrong register. */
rset_clear(allow, osrc);
src = ra_scratch(as, allow8);
}
rset_clear(allow, src);
}
if (ir->o == IR_FSTORE) {
asm_fusefref(as, IR(ir->op1), allow);
} else {
asm_fusexref(as, ir->op1, allow);
if (LJ_32 && ir->o == IR_HIOP) as->mrm.ofs += 4;
}
if (ra_hasreg(src)) {
x86Op xo;
switch (irt_type(ir->t)) {
case IRT_I8: case IRT_U8: xo = XO_MOVtob; src |= FORCE_REX; break;
case IRT_I16: case IRT_U16: xo = XO_MOVtow; break;
case IRT_NUM: xo = XO_MOVSDto; break;
case IRT_FLOAT: xo = XO_MOVSSto; break;
#if LJ_64
case IRT_LIGHTUD: lua_assert(0); /* NYI: mask 64 bit lightuserdata. */
#endif
default:
if (LJ_64 && irt_is64(ir->t))
src |= REX_64;
else
lua_assert(irt_isint(ir->t) || irt_isu32(ir->t) || irt_isaddr(ir->t));
xo = XO_MOVto;
break;
}
emit_mrm(as, xo, src, RID_MRM);
if (!LJ_64 && src != osrc) {
ra_noweak(as, osrc);
emit_rr(as, XO_MOV, src, osrc);
}
} else {
if (irt_isi8(ir->t) || irt_isu8(ir->t)) {
emit_i8(as, k);
emit_mrm(as, XO_MOVmib, 0, RID_MRM);
} else {
lua_assert(irt_is64(ir->t) || irt_isint(ir->t) || irt_isu32(ir->t) ||
irt_isaddr(ir->t));
emit_i32(as, k);
emit_mrm(as, XO_MOVmi, REX_64IR(ir, 0), RID_MRM);
}
}
}
#if LJ_64
static Reg asm_load_lightud64(ASMState *as, IRIns *ir, int typecheck)
{
if (ra_used(ir) || typecheck) {
Reg dest = ra_dest(as, ir, RSET_GPR);
if (typecheck) {
Reg tmp = ra_scratch(as, rset_exclude(RSET_GPR, dest));
asm_guardcc(as, CC_NE);
emit_i8(as, -2);
emit_rr(as, XO_ARITHi8, XOg_CMP, tmp);
emit_shifti(as, XOg_SAR|REX_64, tmp, 47);
emit_rr(as, XO_MOV, tmp|REX_64, dest);
}
return dest;
} else {
return RID_NONE;
}
}
#endif
static void asm_ahuvload(ASMState *as, IRIns *ir)
{
lua_assert(irt_isnum(ir->t) || irt_ispri(ir->t) || irt_isaddr(ir->t) ||
(LJ_DUALNUM && irt_isint(ir->t)));
#if LJ_64
if (irt_islightud(ir->t)) {
Reg dest = asm_load_lightud64(as, ir, 1);
if (ra_hasreg(dest)) {
asm_fuseahuref(as, ir->op1, RSET_GPR);
emit_mrm(as, XO_MOV, dest|REX_64, RID_MRM);
}
return;
} else
#endif
if (ra_used(ir)) {
RegSet allow = irt_isnum(ir->t) ? RSET_FPR : RSET_GPR;
Reg dest = ra_dest(as, ir, allow);
asm_fuseahuref(as, ir->op1, RSET_GPR);
emit_mrm(as, dest < RID_MAX_GPR ? XO_MOV : XMM_MOVRM(as), dest, RID_MRM);
} else {
asm_fuseahuref(as, ir->op1, RSET_GPR);
}
/* Always do the type check, even if the load result is unused. */
as->mrm.ofs += 4;
asm_guardcc(as, irt_isnum(ir->t) ? CC_AE : CC_NE);
if (LJ_64 && irt_type(ir->t) >= IRT_NUM) {
lua_assert(irt_isinteger(ir->t) || irt_isnum(ir->t));
emit_u32(as, LJ_TISNUM);
emit_mrm(as, XO_ARITHi, XOg_CMP, RID_MRM);
} else {
emit_i8(as, irt_toitype(ir->t));
emit_mrm(as, XO_ARITHi8, XOg_CMP, RID_MRM);
}
}
static void asm_ahustore(ASMState *as, IRIns *ir)
{
if (ir->r == RID_SINK)
return;
if (irt_isnum(ir->t)) {
Reg src = ra_alloc1(as, ir->op2, RSET_FPR);
asm_fuseahuref(as, ir->op1, RSET_GPR);
emit_mrm(as, XO_MOVSDto, src, RID_MRM);
#if LJ_64
} else if (irt_islightud(ir->t)) {
Reg src = ra_alloc1(as, ir->op2, RSET_GPR);
asm_fuseahuref(as, ir->op1, rset_exclude(RSET_GPR, src));
emit_mrm(as, XO_MOVto, src|REX_64, RID_MRM);
#endif
} else {
IRIns *irr = IR(ir->op2);
RegSet allow = RSET_GPR;
Reg src = RID_NONE;
if (!irref_isk(ir->op2)) {
src = ra_alloc1(as, ir->op2, allow);
rset_clear(allow, src);
}
asm_fuseahuref(as, ir->op1, allow);
if (ra_hasreg(src)) {
emit_mrm(as, XO_MOVto, src, RID_MRM);
} else if (!irt_ispri(irr->t)) {
lua_assert(irt_isaddr(ir->t) || (LJ_DUALNUM && irt_isinteger(ir->t)));
emit_i32(as, irr->i);
emit_mrm(as, XO_MOVmi, 0, RID_MRM);
}
as->mrm.ofs += 4;
emit_i32(as, (int32_t)irt_toitype(ir->t));
emit_mrm(as, XO_MOVmi, 0, RID_MRM);
}
}
static void asm_sload(ASMState *as, IRIns *ir)
{
int32_t ofs = 8*((int32_t)ir->op1-1) + ((ir->op2 & IRSLOAD_FRAME) ? 4 : 0);
IRType1 t = ir->t;
Reg base;
lua_assert(!(ir->op2 & IRSLOAD_PARENT)); /* Handled by asm_head_side(). */
lua_assert(irt_isguard(t) || !(ir->op2 & IRSLOAD_TYPECHECK));
lua_assert(LJ_DUALNUM ||
!irt_isint(t) || (ir->op2 & (IRSLOAD_CONVERT|IRSLOAD_FRAME)));
if ((ir->op2 & IRSLOAD_CONVERT) && irt_isguard(t) && irt_isint(t)) {
Reg left = ra_scratch(as, RSET_FPR);
asm_tointg(as, ir, left); /* Frees dest reg. Do this before base alloc. */
base = ra_alloc1(as, REF_BASE, RSET_GPR);
emit_rmro(as, XMM_MOVRM(as), left, base, ofs);
t.irt = IRT_NUM; /* Continue with a regular number type check. */
#if LJ_64
} else if (irt_islightud(t)) {
Reg dest = asm_load_lightud64(as, ir, (ir->op2 & IRSLOAD_TYPECHECK));
if (ra_hasreg(dest)) {
base = ra_alloc1(as, REF_BASE, RSET_GPR);
emit_rmro(as, XO_MOV, dest|REX_64, base, ofs);
}
return;
#endif
} else if (ra_used(ir)) {
RegSet allow = irt_isnum(t) ? RSET_FPR : RSET_GPR;
Reg dest = ra_dest(as, ir, allow);
base = ra_alloc1(as, REF_BASE, RSET_GPR);
lua_assert(irt_isnum(t) || irt_isint(t) || irt_isaddr(t));
if ((ir->op2 & IRSLOAD_CONVERT)) {
t.irt = irt_isint(t) ? IRT_NUM : IRT_INT; /* Check for original type. */
emit_rmro(as, irt_isint(t) ? XO_CVTSI2SD : XO_CVTSD2SI, dest, base, ofs);
} else if (irt_isnum(t)) {
emit_rmro(as, XMM_MOVRM(as), dest, base, ofs);
} else {
emit_rmro(as, XO_MOV, dest, base, ofs);
}
} else {
if (!(ir->op2 & IRSLOAD_TYPECHECK))
return; /* No type check: avoid base alloc. */
base = ra_alloc1(as, REF_BASE, RSET_GPR);
}
if ((ir->op2 & IRSLOAD_TYPECHECK)) {
/* Need type check, even if the load result is unused. */
asm_guardcc(as, irt_isnum(t) ? CC_AE : CC_NE);
if (LJ_64 && irt_type(t) >= IRT_NUM) {
lua_assert(irt_isinteger(t) || irt_isnum(t));
emit_u32(as, LJ_TISNUM);
emit_rmro(as, XO_ARITHi, XOg_CMP, base, ofs+4);
} else {
emit_i8(as, irt_toitype(t));
emit_rmro(as, XO_ARITHi8, XOg_CMP, base, ofs+4);
}
}
}
/* -- Allocations --------------------------------------------------------- */
#if LJ_HASFFI
static void asm_cnew(ASMState *as, IRIns *ir)
{
CTState *cts = ctype_ctsG(J2G(as->J));
CTypeID ctypeid = (CTypeID)IR(ir->op1)->i;
CTSize sz = (ir->o == IR_CNEWI || ir->op2 == REF_NIL) ?
lj_ctype_size(cts, ctypeid) : (CTSize)IR(ir->op2)->i;
const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_mem_newgco];
IRRef args[2];
lua_assert(sz != CTSIZE_INVALID);
args[0] = ASMREF_L; /* lua_State *L */
args[1] = ASMREF_TMP1; /* MSize size */
as->gcsteps++;
asm_setupresult(as, ir, ci); /* GCcdata * */
/* Initialize immutable cdata object. */
if (ir->o == IR_CNEWI) {
RegSet allow = (RSET_GPR & ~RSET_SCRATCH);
#if LJ_64
Reg r64 = sz == 8 ? REX_64 : 0;
if (irref_isk(ir->op2)) {
IRIns *irk = IR(ir->op2);
uint64_t k = irk->o == IR_KINT64 ? ir_k64(irk)->u64 :
(uint64_t)(uint32_t)irk->i;
if (sz == 4 || checki32((int64_t)k)) {
emit_i32(as, (int32_t)k);
emit_rmro(as, XO_MOVmi, r64, RID_RET, sizeof(GCcdata));
} else {
emit_movtomro(as, RID_ECX + r64, RID_RET, sizeof(GCcdata));
emit_loadu64(as, RID_ECX, k);
}
} else {
Reg r = ra_alloc1(as, ir->op2, allow);
emit_movtomro(as, r + r64, RID_RET, sizeof(GCcdata));
}
#else
int32_t ofs = sizeof(GCcdata);
if (sz == 8) {
ofs += 4; ir++;
lua_assert(ir->o == IR_HIOP);
}
do {
if (irref_isk(ir->op2)) {
emit_movmroi(as, RID_RET, ofs, IR(ir->op2)->i);
} else {
Reg r = ra_alloc1(as, ir->op2, allow);
emit_movtomro(as, r, RID_RET, ofs);
rset_clear(allow, r);
}
if (ofs == sizeof(GCcdata)) break;
ofs -= 4; ir--;
} while (1);
#endif
lua_assert(sz == 4 || sz == 8);
}
/* Combine initialization of marked, gct and ctypeid. */
emit_movtomro(as, RID_ECX, RID_RET, offsetof(GCcdata, marked));
emit_gri(as, XG_ARITHi(XOg_OR), RID_ECX,
(int32_t)((~LJ_TCDATA<<8)+(ctypeid<<16)));
emit_gri(as, XG_ARITHi(XOg_AND), RID_ECX, LJ_GC_WHITES);
emit_opgl(as, XO_MOVZXb, RID_ECX, gc.currentwhite);
asm_gencall(as, ci, args);
emit_loadi(as, ra_releasetmp(as, ASMREF_TMP1), (int32_t)(sz+sizeof(GCcdata)));
}
#else
#define asm_cnew(as, ir) ((void)0)
#endif
/* -- Write barriers ------------------------------------------------------ */
static void asm_tbar(ASMState *as, IRIns *ir)
{
Reg tab = ra_alloc1(as, ir->op1, RSET_GPR);
Reg tmp = ra_scratch(as, rset_exclude(RSET_GPR, tab));
MCLabel l_end = emit_label(as);
emit_movtomro(as, tmp, tab, offsetof(GCtab, gclist));
emit_setgl(as, tab, gc.grayagain);
emit_getgl(as, tmp, gc.grayagain);
emit_i8(as, ~LJ_GC_BLACK);
emit_rmro(as, XO_ARITHib, XOg_AND, tab, offsetof(GCtab, marked));
emit_sjcc(as, CC_Z, l_end);
emit_i8(as, LJ_GC_BLACK);
emit_rmro(as, XO_GROUP3b, XOg_TEST, tab, offsetof(GCtab, marked));
}
static void asm_obar(ASMState *as, IRIns *ir)
{
const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_gc_barrieruv];
IRRef args[2];
MCLabel l_end;
Reg obj;
/* No need for other object barriers (yet). */
lua_assert(IR(ir->op1)->o == IR_UREFC);
ra_evictset(as, RSET_SCRATCH);
l_end = emit_label(as);
args[0] = ASMREF_TMP1; /* global_State *g */
args[1] = ir->op1; /* TValue *tv */
asm_gencall(as, ci, args);
emit_loada(as, ra_releasetmp(as, ASMREF_TMP1), J2G(as->J));
obj = IR(ir->op1)->r;
emit_sjcc(as, CC_Z, l_end);
emit_i8(as, LJ_GC_WHITES);
if (irref_isk(ir->op2)) {
GCobj *vp = ir_kgc(IR(ir->op2));
emit_rma(as, XO_GROUP3b, XOg_TEST, &vp->gch.marked);
} else {
Reg val = ra_alloc1(as, ir->op2, rset_exclude(RSET_SCRATCH&RSET_GPR, obj));
emit_rmro(as, XO_GROUP3b, XOg_TEST, val, (int32_t)offsetof(GChead, marked));
}
emit_sjcc(as, CC_Z, l_end);
emit_i8(as, LJ_GC_BLACK);
emit_rmro(as, XO_GROUP3b, XOg_TEST, obj,
(int32_t)offsetof(GCupval, marked)-(int32_t)offsetof(GCupval, tv));
}
/* -- FP/int arithmetic and logic operations ------------------------------ */
/* Load reference onto x87 stack. Force a spill to memory if needed. */
static void asm_x87load(ASMState *as, IRRef ref)
{
IRIns *ir = IR(ref);
if (ir->o == IR_KNUM) {
cTValue *tv = ir_knum(ir);
if (tvispzero(tv)) /* Use fldz only for +0. */
emit_x87op(as, XI_FLDZ);
else if (tvispone(tv))
emit_x87op(as, XI_FLD1);
else
emit_rma(as, XO_FLDq, XOg_FLDq, tv);
} else if (ir->o == IR_CONV && ir->op2 == IRCONV_NUM_INT && !ra_used(ir) &&
!irref_isk(ir->op1) && mayfuse(as, ir->op1)) {
IRIns *iri = IR(ir->op1);
emit_rmro(as, XO_FILDd, XOg_FILDd, RID_ESP, ra_spill(as, iri));
} else {
emit_mrm(as, XO_FLDq, XOg_FLDq, asm_fuseload(as, ref, RSET_EMPTY));
}
}
/* Try to rejoin pow from EXP2, MUL and LOG2 (if still unsplit). */
static int fpmjoin_pow(ASMState *as, IRIns *ir)
{
IRIns *irp = IR(ir->op1);
if (irp == ir-1 && irp->o == IR_MUL && !ra_used(irp)) {
IRIns *irpp = IR(irp->op1);
if (irpp == ir-2 && irpp->o == IR_FPMATH &&
irpp->op2 == IRFPM_LOG2 && !ra_used(irpp)) {
/* The modified regs must match with the *.dasc implementation. */
RegSet drop = RSET_RANGE(RID_XMM0, RID_XMM2+1)|RID2RSET(RID_EAX);
IRIns *irx;
if (ra_hasreg(ir->r))
rset_clear(drop, ir->r); /* Dest reg handled below. */
ra_evictset(as, drop);
ra_destreg(as, ir, RID_XMM0);
emit_call(as, lj_vm_pow_sse);
irx = IR(irpp->op1);
if (ra_noreg(irx->r) && ra_gethint(irx->r) == RID_XMM1)
irx->r = RID_INIT; /* Avoid allocating xmm1 for x. */
ra_left(as, RID_XMM0, irpp->op1);
ra_left(as, RID_XMM1, irp->op2);
return 1;
}
}
return 0;
}
static void asm_fpmath(ASMState *as, IRIns *ir)
{
IRFPMathOp fpm = ir->o == IR_FPMATH ? (IRFPMathOp)ir->op2 : IRFPM_OTHER;
if (fpm == IRFPM_SQRT) {
Reg dest = ra_dest(as, ir, RSET_FPR);
Reg left = asm_fuseload(as, ir->op1, RSET_FPR);
emit_mrm(as, XO_SQRTSD, dest, left);
} else if (fpm <= IRFPM_TRUNC) {
if (as->flags & JIT_F_SSE4_1) { /* SSE4.1 has a rounding instruction. */
Reg dest = ra_dest(as, ir, RSET_FPR);
Reg left = asm_fuseload(as, ir->op1, RSET_FPR);
/* ROUNDSD has a 4-byte opcode which doesn't fit in x86Op.
** Let's pretend it's a 3-byte opcode, and compensate afterwards.
** This is atrocious, but the alternatives are much worse.
*/
/* Round down/up/trunc == 1001/1010/1011. */
emit_i8(as, 0x09 + fpm);
emit_mrm(as, XO_ROUNDSD, dest, left);
if (LJ_64 && as->mcp[1] != (MCode)(XO_ROUNDSD >> 16)) {
as->mcp[0] = as->mcp[1]; as->mcp[1] = 0x0f; /* Swap 0F and REX. */
}
*--as->mcp = 0x66; /* 1st byte of ROUNDSD opcode. */
} else { /* Call helper functions for SSE2 variant. */
/* The modified regs must match with the *.dasc implementation. */
RegSet drop = RSET_RANGE(RID_XMM0, RID_XMM3+1)|RID2RSET(RID_EAX);
if (ra_hasreg(ir->r))
rset_clear(drop, ir->r); /* Dest reg handled below. */
ra_evictset(as, drop);
ra_destreg(as, ir, RID_XMM0);
emit_call(as, fpm == IRFPM_FLOOR ? lj_vm_floor_sse :
fpm == IRFPM_CEIL ? lj_vm_ceil_sse : lj_vm_trunc_sse);
ra_left(as, RID_XMM0, ir->op1);
}
} else if (fpm == IRFPM_EXP2 && fpmjoin_pow(as, ir)) {
/* Rejoined to pow(). */
} else { /* Handle x87 ops. */
int32_t ofs = sps_scale(ir->s); /* Use spill slot or temp slots. */
Reg dest = ir->r;
if (ra_hasreg(dest)) {
ra_free(as, dest);
ra_modified(as, dest);
emit_rmro(as, XMM_MOVRM(as), dest, RID_ESP, ofs);
}
emit_rmro(as, XO_FSTPq, XOg_FSTPq, RID_ESP, ofs);
switch (fpm) { /* st0 = lj_vm_*(st0) */
case IRFPM_EXP: emit_call(as, lj_vm_exp_x87); break;
case IRFPM_EXP2: emit_call(as, lj_vm_exp2_x87); break;
case IRFPM_SIN: emit_x87op(as, XI_FSIN); break;
case IRFPM_COS: emit_x87op(as, XI_FCOS); break;
case IRFPM_TAN: emit_x87op(as, XI_FPOP); emit_x87op(as, XI_FPTAN); break;
case IRFPM_LOG: case IRFPM_LOG2: case IRFPM_LOG10:
/* Note: the use of fyl2xp1 would be pointless here. When computing
** log(1.0+eps) the precision is already lost after 1.0 is added.
** Subtracting 1.0 won't recover it. OTOH math.log1p would make sense.
*/
emit_x87op(as, XI_FYL2X); break;
case IRFPM_OTHER:
switch (ir->o) {
case IR_ATAN2:
emit_x87op(as, XI_FPATAN); asm_x87load(as, ir->op2); break;
case IR_LDEXP:
emit_x87op(as, XI_FPOP1); emit_x87op(as, XI_FSCALE); break;
default: lua_assert(0); break;
}
break;
default: lua_assert(0); break;
}
asm_x87load(as, ir->op1);
switch (fpm) {
case IRFPM_LOG: emit_x87op(as, XI_FLDLN2); break;
case IRFPM_LOG2: emit_x87op(as, XI_FLD1); break;
case IRFPM_LOG10: emit_x87op(as, XI_FLDLG2); break;
case IRFPM_OTHER:
if (ir->o == IR_LDEXP) asm_x87load(as, ir->op2);
break;
default: break;
}
}
}
static void asm_fppowi(ASMState *as, IRIns *ir)
{
/* The modified regs must match with the *.dasc implementation. */
RegSet drop = RSET_RANGE(RID_XMM0, RID_XMM1+1)|RID2RSET(RID_EAX);
if (ra_hasreg(ir->r))
rset_clear(drop, ir->r); /* Dest reg handled below. */
ra_evictset(as, drop);
ra_destreg(as, ir, RID_XMM0);
emit_call(as, lj_vm_powi_sse);
ra_left(as, RID_XMM0, ir->op1);
ra_left(as, RID_EAX, ir->op2);
}
#if LJ_64 && LJ_HASFFI
static void asm_arith64(ASMState *as, IRIns *ir, IRCallID id)
{
const CCallInfo *ci = &lj_ir_callinfo[id];
IRRef args[2];
args[0] = ir->op1;
args[1] = ir->op2;
asm_setupresult(as, ir, ci);
asm_gencall(as, ci, args);
}
#endif
static void asm_intmod(ASMState *as, IRIns *ir)
{
const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_vm_modi];
IRRef args[2];
args[0] = ir->op1;
args[1] = ir->op2;
asm_setupresult(as, ir, ci);
asm_gencall(as, ci, args);
}
static int asm_swapops(ASMState *as, IRIns *ir)
{
IRIns *irl = IR(ir->op1);
IRIns *irr = IR(ir->op2);
lua_assert(ra_noreg(irr->r));
if (!irm_iscomm(lj_ir_mode[ir->o]))
return 0; /* Can't swap non-commutative operations. */
if (irref_isk(ir->op2))
return 0; /* Don't swap constants to the left. */
if (ra_hasreg(irl->r))
return 1; /* Swap if left already has a register. */
if (ra_samehint(ir->r, irr->r))
return 1; /* Swap if dest and right have matching hints. */
if (as->curins > as->loopref) { /* In variant part? */
if (ir->op2 < as->loopref && !irt_isphi(irr->t))
return 0; /* Keep invariants on the right. */
if (ir->op1 < as->loopref && !irt_isphi(irl->t))
return 1; /* Swap invariants to the right. */
}
if (opisfusableload(irl->o))
return 1; /* Swap fusable loads to the right. */
return 0; /* Otherwise don't swap. */
}
static void asm_fparith(ASMState *as, IRIns *ir, x86Op xo)
{
IRRef lref = ir->op1;
IRRef rref = ir->op2;
RegSet allow = RSET_FPR;
Reg dest;
Reg right = IR(rref)->r;
if (ra_hasreg(right)) {
rset_clear(allow, right);
ra_noweak(as, right);
}
dest = ra_dest(as, ir, allow);
if (lref == rref) {
right = dest;
} else if (ra_noreg(right)) {
if (asm_swapops(as, ir)) {
IRRef tmp = lref; lref = rref; rref = tmp;
}
right = asm_fuseload(as, rref, rset_clear(allow, dest));
}
emit_mrm(as, xo, dest, right);
ra_left(as, dest, lref);
}
static void asm_intarith(ASMState *as, IRIns *ir, x86Arith xa)
{
IRRef lref = ir->op1;
IRRef rref = ir->op2;
RegSet allow = RSET_GPR;
Reg dest, right;
int32_t k = 0;
if (as->flagmcp == as->mcp) { /* Drop test r,r instruction. */
as->flagmcp = NULL;
as->mcp += (LJ_64 && *as->mcp < XI_TESTb) ? 3 : 2;
}
right = IR(rref)->r;
if (ra_hasreg(right)) {
rset_clear(allow, right);
ra_noweak(as, right);
}
dest = ra_dest(as, ir, allow);
if (lref == rref) {
right = dest;
} else if (ra_noreg(right) && !asm_isk32(as, rref, &k)) {
if (asm_swapops(as, ir)) {
IRRef tmp = lref; lref = rref; rref = tmp;
}
right = asm_fuseloadm(as, rref, rset_clear(allow, dest), irt_is64(ir->t));
}
if (irt_isguard(ir->t)) /* For IR_ADDOV etc. */
asm_guardcc(as, CC_O);
if (xa != XOg_X_IMUL) {
if (ra_hasreg(right))
emit_mrm(as, XO_ARITH(xa), REX_64IR(ir, dest), right);
else
emit_gri(as, XG_ARITHi(xa), REX_64IR(ir, dest), k);
} else if (ra_hasreg(right)) { /* IMUL r, mrm. */
emit_mrm(as, XO_IMUL, REX_64IR(ir, dest), right);
} else { /* IMUL r, r, k. */
/* NYI: use lea/shl/add/sub (FOLD only does 2^k) depending on CPU. */
Reg left = asm_fuseloadm(as, lref, RSET_GPR, irt_is64(ir->t));
x86Op xo;
if (checki8(k)) { emit_i8(as, k); xo = XO_IMULi8;
} else { emit_i32(as, k); xo = XO_IMULi; }
emit_mrm(as, xo, REX_64IR(ir, dest), left);
return;
}
ra_left(as, dest, lref);
}
/* LEA is really a 4-operand ADD with an independent destination register,
** up to two source registers and an immediate. One register can be scaled
** by 1, 2, 4 or 8. This can be used to avoid moves or to fuse several
** instructions.
**
** Currently only a few common cases are supported:
** - 3-operand ADD: y = a+b; y = a+k with a and b already allocated
** - Left ADD fusion: y = (a+b)+k; y = (a+k)+b
** - Right ADD fusion: y = a+(b+k)
** The ommited variants have already been reduced by FOLD.
**
** There are more fusion opportunities, like gathering shifts or joining
** common references. But these are probably not worth the trouble, since
** array indexing is not decomposed and already makes use of all fields
** of the ModRM operand.
*/
static int asm_lea(ASMState *as, IRIns *ir)
{
IRIns *irl = IR(ir->op1);
IRIns *irr = IR(ir->op2);
RegSet allow = RSET_GPR;
Reg dest;
as->mrm.base = as->mrm.idx = RID_NONE;
as->mrm.scale = XM_SCALE1;
as->mrm.ofs = 0;
if (ra_hasreg(irl->r)) {
rset_clear(allow, irl->r);
ra_noweak(as, irl->r);
as->mrm.base = irl->r;
if (irref_isk(ir->op2) || ra_hasreg(irr->r)) {
/* The PHI renaming logic does a better job in some cases. */
if (ra_hasreg(ir->r) &&
((irt_isphi(irl->t) && as->phireg[ir->r] == ir->op1) ||
(irt_isphi(irr->t) && as->phireg[ir->r] == ir->op2)))
return 0;
if (irref_isk(ir->op2)) {
as->mrm.ofs = irr->i;
} else {
rset_clear(allow, irr->r);
ra_noweak(as, irr->r);
as->mrm.idx = irr->r;
}
} else if (irr->o == IR_ADD && mayfuse(as, ir->op2) &&
irref_isk(irr->op2)) {
Reg idx = ra_alloc1(as, irr->op1, allow);
rset_clear(allow, idx);
as->mrm.idx = (uint8_t)idx;
as->mrm.ofs = IR(irr->op2)->i;
} else {
return 0;
}
} else if (ir->op1 != ir->op2 && irl->o == IR_ADD && mayfuse(as, ir->op1) &&
(irref_isk(ir->op2) || irref_isk(irl->op2))) {
Reg idx, base = ra_alloc1(as, irl->op1, allow);
rset_clear(allow, base);
as->mrm.base = (uint8_t)base;
if (irref_isk(ir->op2)) {
as->mrm.ofs = irr->i;
idx = ra_alloc1(as, irl->op2, allow);
} else {
as->mrm.ofs = IR(irl->op2)->i;
idx = ra_alloc1(as, ir->op2, allow);
}
rset_clear(allow, idx);
as->mrm.idx = (uint8_t)idx;
} else {
return 0;
}
dest = ra_dest(as, ir, allow);
emit_mrm(as, XO_LEA, dest, RID_MRM);
return 1; /* Success. */
}
static void asm_add(ASMState *as, IRIns *ir)
{
if (irt_isnum(ir->t))
asm_fparith(as, ir, XO_ADDSD);
else if ((as->flags & JIT_F_LEA_AGU) || as->flagmcp == as->mcp ||
irt_is64(ir->t) || !asm_lea(as, ir))
asm_intarith(as, ir, XOg_ADD);
}
static void asm_neg_not(ASMState *as, IRIns *ir, x86Group3 xg)
{
Reg dest = ra_dest(as, ir, RSET_GPR);
emit_rr(as, XO_GROUP3, REX_64IR(ir, xg), dest);
ra_left(as, dest, ir->op1);
}
static void asm_min_max(ASMState *as, IRIns *ir, int cc)
{
Reg right, dest = ra_dest(as, ir, RSET_GPR);
IRRef lref = ir->op1, rref = ir->op2;
if (irref_isk(rref)) { lref = rref; rref = ir->op1; }
right = ra_alloc1(as, rref, rset_exclude(RSET_GPR, dest));
emit_rr(as, XO_CMOV + (cc<<24), REX_64IR(ir, dest), right);
emit_rr(as, XO_CMP, REX_64IR(ir, dest), right);
ra_left(as, dest, lref);
}
static void asm_bitswap(ASMState *as, IRIns *ir)
{
Reg dest = ra_dest(as, ir, RSET_GPR);
as->mcp = emit_op(XO_BSWAP + ((dest&7) << 24),
REX_64IR(ir, 0), dest, 0, as->mcp, 1);
ra_left(as, dest, ir->op1);
}
static void asm_bitshift(ASMState *as, IRIns *ir, x86Shift xs)
{
IRRef rref = ir->op2;
IRIns *irr = IR(rref);
Reg dest;
if (irref_isk(rref)) { /* Constant shifts. */
int shift;
dest = ra_dest(as, ir, RSET_GPR);
shift = irr->i & (irt_is64(ir->t) ? 63 : 31);
switch (shift) {
case 0: break;
case 1: emit_rr(as, XO_SHIFT1, REX_64IR(ir, xs), dest); break;
default: emit_shifti(as, REX_64IR(ir, xs), dest, shift); break;
}
} else { /* Variable shifts implicitly use register cl (i.e. ecx). */
Reg right;
dest = ra_dest(as, ir, rset_exclude(RSET_GPR, RID_ECX));
if (dest == RID_ECX) {
dest = ra_scratch(as, rset_exclude(RSET_GPR, RID_ECX));
emit_rr(as, XO_MOV, RID_ECX, dest);
}
right = irr->r;
if (ra_noreg(right))
right = ra_allocref(as, rref, RID2RSET(RID_ECX));
else if (right != RID_ECX)
ra_scratch(as, RID2RSET(RID_ECX));
emit_rr(as, XO_SHIFTcl, REX_64IR(ir, xs), dest);
ra_noweak(as, right);
if (right != RID_ECX)
emit_rr(as, XO_MOV, RID_ECX, right);
}
ra_left(as, dest, ir->op1);
/*
** Note: avoid using the flags resulting from a shift or rotate!
** All of them cause a partial flag stall, except for r,1 shifts
** (but not rotates). And a shift count of 0 leaves the flags unmodified.
*/
}
/* -- Comparisons --------------------------------------------------------- */
/* Virtual flags for unordered FP comparisons. */
#define VCC_U 0x1000 /* Unordered. */
#define VCC_P 0x2000 /* Needs extra CC_P branch. */
#define VCC_S 0x4000 /* Swap avoids CC_P branch. */
#define VCC_PS (VCC_P|VCC_S)
/* Map of comparisons to flags. ORDER IR. */
#define COMPFLAGS(ci, cin, cu, cf) ((ci)+((cu)<<4)+((cin)<<8)+(cf))
static const uint16_t asm_compmap[IR_ABC+1] = {
/* signed non-eq unsigned flags */
/* LT */ COMPFLAGS(CC_GE, CC_G, CC_AE, VCC_PS),
/* GE */ COMPFLAGS(CC_L, CC_L, CC_B, 0),
/* LE */ COMPFLAGS(CC_G, CC_G, CC_A, VCC_PS),
/* GT */ COMPFLAGS(CC_LE, CC_L, CC_BE, 0),
/* ULT */ COMPFLAGS(CC_AE, CC_A, CC_AE, VCC_U),
/* UGE */ COMPFLAGS(CC_B, CC_B, CC_B, VCC_U|VCC_PS),
/* ULE */ COMPFLAGS(CC_A, CC_A, CC_A, VCC_U),
/* UGT */ COMPFLAGS(CC_BE, CC_B, CC_BE, VCC_U|VCC_PS),
/* EQ */ COMPFLAGS(CC_NE, CC_NE, CC_NE, VCC_P),
/* NE */ COMPFLAGS(CC_E, CC_E, CC_E, VCC_U|VCC_P),
/* ABC */ COMPFLAGS(CC_BE, CC_B, CC_BE, VCC_U|VCC_PS) /* Same as UGT. */
};
/* FP and integer comparisons. */
static void asm_comp(ASMState *as, IRIns *ir, uint32_t cc)
{
if (irt_isnum(ir->t)) {
IRRef lref = ir->op1;
IRRef rref = ir->op2;
Reg left, right;
MCLabel l_around;
/*
** An extra CC_P branch is required to preserve ordered/unordered
** semantics for FP comparisons. This can be avoided by swapping
** the operands and inverting the condition (except for EQ and UNE).
** So always try to swap if possible.
**
** Another option would be to swap operands to achieve better memory
** operand fusion. But it's unlikely that this outweighs the cost
** of the extra branches.
*/
if (cc & VCC_S) { /* Swap? */
IRRef tmp = lref; lref = rref; rref = tmp;
cc ^= (VCC_PS|(5<<4)); /* A <-> B, AE <-> BE, PS <-> none */
}
left = ra_alloc1(as, lref, RSET_FPR);
right = asm_fuseload(as, rref, rset_exclude(RSET_FPR, left));
l_around = emit_label(as);
asm_guardcc(as, cc >> 4);
if (cc & VCC_P) { /* Extra CC_P branch required? */
if (!(cc & VCC_U)) {
asm_guardcc(as, CC_P); /* Branch to exit for ordered comparisons. */
} else if (l_around != as->invmcp) {
emit_sjcc(as, CC_P, l_around); /* Branch around for unordered. */
} else {
/* Patched to mcloop by asm_loop_fixup. */
as->loopinv = 2;
if (as->realign)
emit_sjcc(as, CC_P, as->mcp);
else
emit_jcc(as, CC_P, as->mcp);
}
}
emit_mrm(as, XO_UCOMISD, left, right);
} else {
IRRef lref = ir->op1, rref = ir->op2;
IROp leftop = (IROp)(IR(lref)->o);
Reg r64 = REX_64IR(ir, 0);
int32_t imm = 0;
lua_assert(irt_is64(ir->t) || irt_isint(ir->t) ||
irt_isu32(ir->t) || irt_isaddr(ir->t) || irt_isu8(ir->t));
/* Swap constants (only for ABC) and fusable loads to the right. */
if (irref_isk(lref) || (!irref_isk(rref) && opisfusableload(leftop))) {
if ((cc & 0xc) == 0xc) cc ^= 0x53; /* L <-> G, LE <-> GE */
else if ((cc & 0xa) == 0x2) cc ^= 0x55; /* A <-> B, AE <-> BE */
lref = ir->op2; rref = ir->op1;
}
if (asm_isk32(as, rref, &imm)) {
IRIns *irl = IR(lref);
/* Check wether we can use test ins. Not for unsigned, since CF=0. */
int usetest = (imm == 0 && (cc & 0xa) != 0x2);
if (usetest && irl->o == IR_BAND && irl+1 == ir && !ra_used(irl)) {
/* Combine comp(BAND(ref, r/imm), 0) into test mrm, r/imm. */
Reg right, left = RID_NONE;
RegSet allow = RSET_GPR;
if (!asm_isk32(as, irl->op2, &imm)) {
left = ra_alloc1(as, irl->op2, allow);
rset_clear(allow, left);
} else { /* Try to Fuse IRT_I8/IRT_U8 loads, too. See below. */
IRIns *irll = IR(irl->op1);
if (opisfusableload((IROp)irll->o) &&
(irt_isi8(irll->t) || irt_isu8(irll->t))) {
IRType1 origt = irll->t; /* Temporarily flip types. */
irll->t.irt = (irll->t.irt & ~IRT_TYPE) | IRT_INT;
as->curins--; /* Skip to BAND to avoid failing in noconflict(). */
right = asm_fuseload(as, irl->op1, RSET_GPR);
as->curins++;
irll->t = origt;
if (right != RID_MRM) goto test_nofuse;
/* Fusion succeeded, emit test byte mrm, imm8. */
asm_guardcc(as, cc);
emit_i8(as, (imm & 0xff));
emit_mrm(as, XO_GROUP3b, XOg_TEST, RID_MRM);
return;
}
}
as->curins--; /* Skip to BAND to avoid failing in noconflict(). */
right = asm_fuseloadm(as, irl->op1, allow, r64);
as->curins++; /* Undo the above. */
test_nofuse:
asm_guardcc(as, cc);
if (ra_noreg(left)) {
emit_i32(as, imm);
emit_mrm(as, XO_GROUP3, r64 + XOg_TEST, right);
} else {
emit_mrm(as, XO_TEST, r64 + left, right);
}
} else {
Reg left;
if (opisfusableload((IROp)irl->o) &&
((irt_isu8(irl->t) && checku8(imm)) ||
((irt_isi8(irl->t) || irt_isi16(irl->t)) && checki8(imm)) ||
(irt_isu16(irl->t) && checku16(imm) && checki8((int16_t)imm)))) {
/* Only the IRT_INT case is fused by asm_fuseload.
** The IRT_I8/IRT_U8 loads and some IRT_I16/IRT_U16 loads
** are handled here.
** Note that cmp word [mem], imm16 should not be generated,
** since it has a length-changing prefix. Compares of a word
** against a sign-extended imm8 are ok, however.
*/
IRType1 origt = irl->t; /* Temporarily flip types. */
irl->t.irt = (irl->t.irt & ~IRT_TYPE) | IRT_INT;
left = asm_fuseload(as, lref, RSET_GPR);
irl->t = origt;
if (left == RID_MRM) { /* Fusion succeeded? */
if (irt_isu8(irl->t) || irt_isu16(irl->t))
cc >>= 4; /* Need unsigned compare. */
asm_guardcc(as, cc);
emit_i8(as, imm);
emit_mrm(as, (irt_isi8(origt) || irt_isu8(origt)) ?
XO_ARITHib : XO_ARITHiw8, r64 + XOg_CMP, RID_MRM);
return;
} /* Otherwise handle register case as usual. */
} else {
left = asm_fuseloadm(as, lref,
irt_isu8(ir->t) ? RSET_GPR8 : RSET_GPR, r64);
}
asm_guardcc(as, cc);
if (usetest && left != RID_MRM) {
/* Use test r,r instead of cmp r,0. */
x86Op xo = XO_TEST;
if (irt_isu8(ir->t)) {
lua_assert(ir->o == IR_EQ || ir->o == IR_NE);
xo = XO_TESTb;
if (!rset_test(RSET_RANGE(RID_EAX, RID_EBX+1), left)) {
if (LJ_64) {
left |= FORCE_REX;
} else {
emit_i32(as, 0xff);
emit_mrm(as, XO_GROUP3, XOg_TEST, left);
return;
}
}
}
emit_rr(as, xo, r64 + left, left);
if (irl+1 == ir) /* Referencing previous ins? */
as->flagmcp = as->mcp; /* Set flag to drop test r,r if possible. */
} else {
emit_gmrmi(as, XG_ARITHi(XOg_CMP), r64 + left, imm);
}
}
} else {
Reg left = ra_alloc1(as, lref, RSET_GPR);
Reg right = asm_fuseloadm(as, rref, rset_exclude(RSET_GPR, left), r64);
asm_guardcc(as, cc);
emit_mrm(as, XO_CMP, r64 + left, right);
}
}
}
#if LJ_32 && LJ_HASFFI
/* 64 bit integer comparisons in 32 bit mode. */
static void asm_comp_int64(ASMState *as, IRIns *ir)
{
uint32_t cc = asm_compmap[(ir-1)->o];
RegSet allow = RSET_GPR;
Reg lefthi = RID_NONE, leftlo = RID_NONE;
Reg righthi = RID_NONE, rightlo = RID_NONE;
MCLabel l_around;
x86ModRM mrm;
as->curins--; /* Skip loword ins. Avoids failing in noconflict(), too. */
/* Allocate/fuse hiword operands. */
if (irref_isk(ir->op2)) {
lefthi = asm_fuseload(as, ir->op1, allow);
} else {
lefthi = ra_alloc1(as, ir->op1, allow);
rset_clear(allow, lefthi);
righthi = asm_fuseload(as, ir->op2, allow);
if (righthi == RID_MRM) {
if (as->mrm.base != RID_NONE) rset_clear(allow, as->mrm.base);
if (as->mrm.idx != RID_NONE) rset_clear(allow, as->mrm.idx);
} else {
rset_clear(allow, righthi);
}
}
mrm = as->mrm; /* Save state for hiword instruction. */
/* Allocate/fuse loword operands. */
if (irref_isk((ir-1)->op2)) {
leftlo = asm_fuseload(as, (ir-1)->op1, allow);
} else {
leftlo = ra_alloc1(as, (ir-1)->op1, allow);
rset_clear(allow, leftlo);
rightlo = asm_fuseload(as, (ir-1)->op2, allow);
}
/* All register allocations must be performed _before_ this point. */
l_around = emit_label(as);
as->invmcp = as->flagmcp = NULL; /* Cannot use these optimizations. */
/* Loword comparison and branch. */
asm_guardcc(as, cc >> 4); /* Always use unsigned compare for loword. */
if (ra_noreg(rightlo)) {
int32_t imm = IR((ir-1)->op2)->i;
if (imm == 0 && ((cc >> 4) & 0xa) != 0x2 && leftlo != RID_MRM)
emit_rr(as, XO_TEST, leftlo, leftlo);
else
emit_gmrmi(as, XG_ARITHi(XOg_CMP), leftlo, imm);
} else {
emit_mrm(as, XO_CMP, leftlo, rightlo);
}
/* Hiword comparison and branches. */
if ((cc & 15) != CC_NE)
emit_sjcc(as, CC_NE, l_around); /* Hiword unequal: skip loword compare. */
if ((cc & 15) != CC_E)
asm_guardcc(as, cc >> 8); /* Hiword compare without equality check. */
as->mrm = mrm; /* Restore state. */
if (ra_noreg(righthi)) {
int32_t imm = IR(ir->op2)->i;
if (imm == 0 && (cc & 0xa) != 0x2 && lefthi != RID_MRM)
emit_rr(as, XO_TEST, lefthi, lefthi);
else
emit_gmrmi(as, XG_ARITHi(XOg_CMP), lefthi, imm);
} else {
emit_mrm(as, XO_CMP, lefthi, righthi);
}
}
#endif
/* -- Support for 64 bit ops in 32 bit mode ------------------------------- */
/* Hiword op of a split 64 bit op. Previous op must be the loword op. */
static void asm_hiop(ASMState *as, IRIns *ir)
{
#if LJ_32 && LJ_HASFFI
/* HIOP is marked as a store because it needs its own DCE logic. */
int uselo = ra_used(ir-1), usehi = ra_used(ir); /* Loword/hiword used? */
if (LJ_UNLIKELY(!(as->flags & JIT_F_OPT_DCE))) uselo = usehi = 1;
if ((ir-1)->o == IR_CONV) { /* Conversions to/from 64 bit. */
if (usehi || uselo) {
if (irt_isfp(ir->t))
asm_conv_fp_int64(as, ir);
else
asm_conv_int64_fp(as, ir);
}
as->curins--; /* Always skip the CONV. */
return;
} else if ((ir-1)->o <= IR_NE) { /* 64 bit integer comparisons. ORDER IR. */
asm_comp_int64(as, ir);
return;
} else if ((ir-1)->o == IR_XSTORE) {
if ((ir-1)->r != RID_SINK)
asm_fxstore(as, ir);
return;
}
if (!usehi) return; /* Skip unused hiword op for all remaining ops. */
switch ((ir-1)->o) {
case IR_ADD:
as->flagmcp = NULL;
as->curins--;
asm_intarith(as, ir, XOg_ADC);
asm_intarith(as, ir-1, XOg_ADD);
break;
case IR_SUB:
as->flagmcp = NULL;
as->curins--;
asm_intarith(as, ir, XOg_SBB);
asm_intarith(as, ir-1, XOg_SUB);
break;
case IR_NEG: {
Reg dest = ra_dest(as, ir, RSET_GPR);
emit_rr(as, XO_GROUP3, XOg_NEG, dest);
emit_i8(as, 0);
emit_rr(as, XO_ARITHi8, XOg_ADC, dest);
ra_left(as, dest, ir->op1);
as->curins--;
asm_neg_not(as, ir-1, XOg_NEG);
break;
}
case IR_CALLN:
case IR_CALLXS:
if (!uselo)
ra_allocref(as, ir->op1, RID2RSET(RID_RETLO)); /* Mark lo op as used. */
break;
case IR_CNEWI:
/* Nothing to do here. Handled by CNEWI itself. */
break;
default: lua_assert(0); break;
}
#else
UNUSED(as); UNUSED(ir); lua_assert(0); /* Unused on x64 or without FFI. */
#endif
}
/* -- Stack handling ------------------------------------------------------ */
/* Check Lua stack size for overflow. Use exit handler as fallback. */
static void asm_stack_check(ASMState *as, BCReg topslot,
IRIns *irp, RegSet allow, ExitNo exitno)
{
/* Try to get an unused temp. register, otherwise spill/restore eax. */
Reg pbase = irp ? irp->r : RID_BASE;
Reg r = allow ? rset_pickbot(allow) : RID_EAX;
emit_jcc(as, CC_B, exitstub_addr(as->J, exitno));
if (allow == RSET_EMPTY) /* Restore temp. register. */
emit_rmro(as, XO_MOV, r|REX_64, RID_ESP, 0);
else
ra_modified(as, r);
emit_gri(as, XG_ARITHi(XOg_CMP), r, (int32_t)(8*topslot));
if (ra_hasreg(pbase) && pbase != r)
emit_rr(as, XO_ARITH(XOg_SUB), r, pbase);
else
emit_rmro(as, XO_ARITH(XOg_SUB), r, RID_NONE,
ptr2addr(&J2G(as->J)->jit_base));
emit_rmro(as, XO_MOV, r, r, offsetof(lua_State, maxstack));
emit_getgl(as, r, jit_L);
if (allow == RSET_EMPTY) /* Spill temp. register. */
emit_rmro(as, XO_MOVto, r|REX_64, RID_ESP, 0);
}
/* Restore Lua stack from on-trace state. */
static void asm_stack_restore(ASMState *as, SnapShot *snap)
{
SnapEntry *map = &as->T->snapmap[snap->mapofs];
SnapEntry *flinks = &as->T->snapmap[snap_nextofs(as->T, snap)-1];
MSize n, nent = snap->nent;
/* Store the value of all modified slots to the Lua stack. */
for (n = 0; n < nent; n++) {
SnapEntry sn = map[n];
BCReg s = snap_slot(sn);
int32_t ofs = 8*((int32_t)s-1);
IRRef ref = snap_ref(sn);
IRIns *ir = IR(ref);
if ((sn & SNAP_NORESTORE))
continue;
if (irt_isnum(ir->t)) {
Reg src = ra_alloc1(as, ref, RSET_FPR);
emit_rmro(as, XO_MOVSDto, src, RID_BASE, ofs);
} else {
lua_assert(irt_ispri(ir->t) || irt_isaddr(ir->t) ||
(LJ_DUALNUM && irt_isinteger(ir->t)));
if (!irref_isk(ref)) {
Reg src = ra_alloc1(as, ref, rset_exclude(RSET_GPR, RID_BASE));
emit_movtomro(as, REX_64IR(ir, src), RID_BASE, ofs);
} else if (!irt_ispri(ir->t)) {
emit_movmroi(as, RID_BASE, ofs, ir->i);
}
if ((sn & (SNAP_CONT|SNAP_FRAME))) {
if (s != 0) /* Do not overwrite link to previous frame. */
emit_movmroi(as, RID_BASE, ofs+4, (int32_t)(*flinks--));
} else {
if (!(LJ_64 && irt_islightud(ir->t)))
emit_movmroi(as, RID_BASE, ofs+4, irt_toitype(ir->t));
}
}
checkmclim(as);
}
lua_assert(map + nent == flinks);
}
/* -- GC handling --------------------------------------------------------- */
/* Check GC threshold and do one or more GC steps. */
static void asm_gc_check(ASMState *as)
{
const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_gc_step_jit];
IRRef args[2];
MCLabel l_end;
Reg tmp;
ra_evictset(as, RSET_SCRATCH);
l_end = emit_label(as);
/* Exit trace if in GCSatomic or GCSfinalize. Avoids syncing GC objects. */
asm_guardcc(as, CC_NE); /* Assumes asm_snap_prep() already done. */
emit_rr(as, XO_TEST, RID_RET, RID_RET);
args[0] = ASMREF_TMP1; /* global_State *g */
args[1] = ASMREF_TMP2; /* MSize steps */
asm_gencall(as, ci, args);
tmp = ra_releasetmp(as, ASMREF_TMP1);
emit_loada(as, tmp, J2G(as->J));
emit_loadi(as, ra_releasetmp(as, ASMREF_TMP2), as->gcsteps);
/* Jump around GC step if GC total < GC threshold. */
emit_sjcc(as, CC_B, l_end);
emit_opgl(as, XO_ARITH(XOg_CMP), tmp, gc.threshold);
emit_getgl(as, tmp, gc.total);
as->gcsteps = 0;
checkmclim(as);
}
/* -- Loop handling ------------------------------------------------------- */
/* Fixup the loop branch. */
static void asm_loop_fixup(ASMState *as)
{
MCode *p = as->mctop;
MCode *target = as->mcp;
if (as->realign) { /* Realigned loops use short jumps. */
as->realign = NULL; /* Stop another retry. */
lua_assert(((intptr_t)target & 15) == 0);
if (as->loopinv) { /* Inverted loop branch? */
p -= 5;
p[0] = XI_JMP;
lua_assert(target - p >= -128);
p[-1] = (MCode)(target - p); /* Patch sjcc. */
if (as->loopinv == 2)
p[-3] = (MCode)(target - p + 2); /* Patch opt. short jp. */
} else {
lua_assert(target - p >= -128);
p[-1] = (MCode)(int8_t)(target - p); /* Patch short jmp. */
p[-2] = XI_JMPs;
}
} else {
MCode *newloop;
p[-5] = XI_JMP;
if (as->loopinv) { /* Inverted loop branch? */
/* asm_guardcc already inverted the jcc and patched the jmp. */
p -= 5;
newloop = target+4;
*(int32_t *)(p-4) = (int32_t)(target - p); /* Patch jcc. */
if (as->loopinv == 2) {
*(int32_t *)(p-10) = (int32_t)(target - p + 6); /* Patch opt. jp. */
newloop = target+8;
}
} else { /* Otherwise just patch jmp. */
*(int32_t *)(p-4) = (int32_t)(target - p);
newloop = target+3;
}
/* Realign small loops and shorten the loop branch. */
if (newloop >= p - 128) {
as->realign = newloop; /* Force a retry and remember alignment. */
as->curins = as->stopins; /* Abort asm_trace now. */
as->T->nins = as->orignins; /* Remove any added renames. */
}
}
}
/* -- Head of trace ------------------------------------------------------- */
/* Coalesce BASE register for a root trace. */
static void asm_head_root_base(ASMState *as)
{
IRIns *ir = IR(REF_BASE);
Reg r = ir->r;
if (ra_hasreg(r)) {
ra_free(as, r);
if (rset_test(as->modset, r))
ir->r = RID_INIT; /* No inheritance for modified BASE register. */
if (r != RID_BASE)
emit_rr(as, XO_MOV, r, RID_BASE);
}
}
/* Coalesce or reload BASE register for a side trace. */
static RegSet asm_head_side_base(ASMState *as, IRIns *irp, RegSet allow)
{
IRIns *ir = IR(REF_BASE);
Reg r = ir->r;
if (ra_hasreg(r)) {
ra_free(as, r);
if (rset_test(as->modset, r))
ir->r = RID_INIT; /* No inheritance for modified BASE register. */
if (irp->r == r) {
rset_clear(allow, r); /* Mark same BASE register as coalesced. */
} else if (ra_hasreg(irp->r) && rset_test(as->freeset, irp->r)) {
rset_clear(allow, irp->r);
emit_rr(as, XO_MOV, r, irp->r); /* Move from coalesced parent reg. */
} else {
emit_getgl(as, r, jit_base); /* Otherwise reload BASE. */
}
}
return allow;
}
/* -- Tail of trace ------------------------------------------------------- */
/* Fixup the tail code. */
static void asm_tail_fixup(ASMState *as, TraceNo lnk)
{
/* Note: don't use as->mcp swap + emit_*: emit_op overwrites more bytes. */
MCode *p = as->mctop;
MCode *target, *q;
int32_t spadj = as->T->spadjust;
if (spadj == 0) {
p -= ((as->flags & JIT_F_LEA_AGU) ? 7 : 6) + (LJ_64 ? 1 : 0);
} else {
MCode *p1;
/* Patch stack adjustment. */
if (checki8(spadj)) {
p -= 3;
p1 = p-6;
*p1 = (MCode)spadj;
} else {
p1 = p-9;
*(int32_t *)p1 = spadj;
}
if ((as->flags & JIT_F_LEA_AGU)) {
#if LJ_64
p1[-4] = 0x48;
#endif
p1[-3] = (MCode)XI_LEA;
p1[-2] = MODRM(checki8(spadj) ? XM_OFS8 : XM_OFS32, RID_ESP, RID_ESP);
p1[-1] = MODRM(XM_SCALE1, RID_ESP, RID_ESP);
} else {
#if LJ_64
p1[-3] = 0x48;
#endif
p1[-2] = (MCode)(checki8(spadj) ? XI_ARITHi8 : XI_ARITHi);
p1[-1] = MODRM(XM_REG, XOg_ADD, RID_ESP);
}
}
/* Patch exit branch. */
target = lnk ? traceref(as->J, lnk)->mcode : (MCode *)lj_vm_exit_interp;
*(int32_t *)(p-4) = jmprel(p, target);
p[-5] = XI_JMP;
/* Drop unused mcode tail. Fill with NOPs to make the prefetcher happy. */
for (q = as->mctop-1; q >= p; q--)
*q = XI_NOP;
as->mctop = p;
}
/* Prepare tail of code. */
static void asm_tail_prep(ASMState *as)
{
MCode *p = as->mctop;
/* Realign and leave room for backwards loop branch or exit branch. */
if (as->realign) {
int i = ((int)(intptr_t)as->realign) & 15;
/* Fill unused mcode tail with NOPs to make the prefetcher happy. */
while (i-- > 0)
*--p = XI_NOP;
as->mctop = p;
p -= (as->loopinv ? 5 : 2); /* Space for short/near jmp. */
} else {
p -= 5; /* Space for exit branch (near jmp). */
}
if (as->loopref) {
as->invmcp = as->mcp = p;
} else {
/* Leave room for ESP adjustment: add esp, imm or lea esp, [esp+imm] */
as->mcp = p - (((as->flags & JIT_F_LEA_AGU) ? 7 : 6) + (LJ_64 ? 1 : 0));
as->invmcp = NULL;
}
}
/* -- Instruction dispatch ------------------------------------------------ */
/* Assemble a single instruction. */
static void asm_ir(ASMState *as, IRIns *ir)
{
switch ((IROp)ir->o) {
/* Miscellaneous ops. */
case IR_LOOP: asm_loop(as); break;
case IR_NOP: case IR_XBAR: lua_assert(!ra_used(ir)); break;
case IR_USE:
ra_alloc1(as, ir->op1, irt_isfp(ir->t) ? RSET_FPR : RSET_GPR); break;
case IR_PHI: asm_phi(as, ir); break;
case IR_HIOP: asm_hiop(as, ir); break;
case IR_GCSTEP: asm_gcstep(as, ir); break;
/* Guarded assertions. */
case IR_LT: case IR_GE: case IR_LE: case IR_GT:
case IR_ULT: case IR_UGE: case IR_ULE: case IR_UGT:
case IR_EQ: case IR_NE: case IR_ABC:
asm_comp(as, ir, asm_compmap[ir->o]);
break;
case IR_RETF: asm_retf(as, ir); break;
/* Bit ops. */
case IR_BNOT: asm_neg_not(as, ir, XOg_NOT); break;
case IR_BSWAP: asm_bitswap(as, ir); break;
case IR_BAND: asm_intarith(as, ir, XOg_AND); break;
case IR_BOR: asm_intarith(as, ir, XOg_OR); break;
case IR_BXOR: asm_intarith(as, ir, XOg_XOR); break;
case IR_BSHL: asm_bitshift(as, ir, XOg_SHL); break;
case IR_BSHR: asm_bitshift(as, ir, XOg_SHR); break;
case IR_BSAR: asm_bitshift(as, ir, XOg_SAR); break;
case IR_BROL: asm_bitshift(as, ir, XOg_ROL); break;
case IR_BROR: asm_bitshift(as, ir, XOg_ROR); break;
/* Arithmetic ops. */
case IR_ADD: asm_add(as, ir); break;
case IR_SUB:
if (irt_isnum(ir->t))
asm_fparith(as, ir, XO_SUBSD);
else /* Note: no need for LEA trick here. i-k is encoded as i+(-k). */
asm_intarith(as, ir, XOg_SUB);
break;
case IR_MUL:
if (irt_isnum(ir->t))
asm_fparith(as, ir, XO_MULSD);
else
asm_intarith(as, ir, XOg_X_IMUL);
break;
case IR_DIV:
#if LJ_64 && LJ_HASFFI
if (!irt_isnum(ir->t))
asm_arith64(as, ir, irt_isi64(ir->t) ? IRCALL_lj_carith_divi64 :
IRCALL_lj_carith_divu64);
else
#endif
asm_fparith(as, ir, XO_DIVSD);
break;
case IR_MOD:
#if LJ_64 && LJ_HASFFI
if (!irt_isint(ir->t))
asm_arith64(as, ir, irt_isi64(ir->t) ? IRCALL_lj_carith_modi64 :
IRCALL_lj_carith_modu64);
else
#endif
asm_intmod(as, ir);
break;
case IR_NEG:
if (irt_isnum(ir->t))
asm_fparith(as, ir, XO_XORPS);
else
asm_neg_not(as, ir, XOg_NEG);
break;
case IR_ABS: asm_fparith(as, ir, XO_ANDPS); break;
case IR_MIN:
if (irt_isnum(ir->t))
asm_fparith(as, ir, XO_MINSD);
else
asm_min_max(as, ir, CC_G);
break;
case IR_MAX:
if (irt_isnum(ir->t))
asm_fparith(as, ir, XO_MAXSD);
else
asm_min_max(as, ir, CC_L);
break;
case IR_FPMATH: case IR_ATAN2: case IR_LDEXP:
asm_fpmath(as, ir);
break;
case IR_POW:
#if LJ_64 && LJ_HASFFI
if (!irt_isnum(ir->t))
asm_arith64(as, ir, irt_isi64(ir->t) ? IRCALL_lj_carith_powi64 :
IRCALL_lj_carith_powu64);
else
#endif
asm_fppowi(as, ir);
break;
/* Overflow-checking arithmetic ops. Note: don't use LEA here! */
case IR_ADDOV: asm_intarith(as, ir, XOg_ADD); break;
case IR_SUBOV: asm_intarith(as, ir, XOg_SUB); break;
case IR_MULOV: asm_intarith(as, ir, XOg_X_IMUL); break;
/* Memory references. */
case IR_AREF: asm_aref(as, ir); break;
case IR_HREF: asm_href(as, ir); break;
case IR_HREFK: asm_hrefk(as, ir); break;
case IR_NEWREF: asm_newref(as, ir); break;
case IR_UREFO: case IR_UREFC: asm_uref(as, ir); break;
case IR_FREF: asm_fref(as, ir); break;
case IR_STRREF: asm_strref(as, ir); break;
/* Loads and stores. */
case IR_ALOAD: case IR_HLOAD: case IR_ULOAD: case IR_VLOAD:
asm_ahuvload(as, ir);
break;
case IR_FLOAD: case IR_XLOAD: asm_fxload(as, ir); break;
case IR_SLOAD: asm_sload(as, ir); break;
case IR_ASTORE: case IR_HSTORE: case IR_USTORE: asm_ahustore(as, ir); break;
case IR_FSTORE: case IR_XSTORE: asm_fxstore(as, ir); break;
/* Allocations. */
case IR_SNEW: case IR_XSNEW: asm_snew(as, ir); break;
case IR_TNEW: asm_tnew(as, ir); break;
case IR_TDUP: asm_tdup(as, ir); break;
case IR_CNEW: case IR_CNEWI: asm_cnew(as, ir); break;
/* Write barriers. */
case IR_TBAR: asm_tbar(as, ir); break;
case IR_OBAR: asm_obar(as, ir); break;
/* Type conversions. */
case IR_TOBIT: asm_tobit(as, ir); break;
case IR_CONV: asm_conv(as, ir); break;
case IR_TOSTR: asm_tostr(as, ir); break;
case IR_STRTO: asm_strto(as, ir); break;
/* Calls. */
case IR_CALLN: case IR_CALLL: case IR_CALLS: asm_call(as, ir); break;
case IR_CALLXS: asm_callx(as, ir); break;
case IR_CARG: break;
default:
setintV(&as->J->errinfo, ir->o);
lj_trace_err_info(as->J, LJ_TRERR_NYIIR);
break;
}
}
/* -- Trace setup --------------------------------------------------------- */
/* Ensure there are enough stack slots for call arguments. */
static Reg asm_setup_call_slots(ASMState *as, IRIns *ir, const CCallInfo *ci)
{
IRRef args[CCI_NARGS_MAX*2];
int nslots;
asm_collectargs(as, ir, ci, args);
nslots = asm_count_call_slots(as, ci, args);
if (nslots > as->evenspill) /* Leave room for args in stack slots. */
as->evenspill = nslots;
#if LJ_64
return irt_isfp(ir->t) ? REGSP_HINT(RID_FPRET) : REGSP_HINT(RID_RET);
#else
return irt_isfp(ir->t) ? REGSP_INIT : REGSP_HINT(RID_RET);
#endif
}
/* Target-specific setup. */
static void asm_setup_target(ASMState *as)
{
asm_exitstub_setup(as, as->T->nsnap);
}
/* -- Trace patching ------------------------------------------------------ */
/* Patch exit jumps of existing machine code to a new target. */
void lj_asm_patchexit(jit_State *J, GCtrace *T, ExitNo exitno, MCode *target)
{
MCode *p = T->mcode;
MCode *mcarea = lj_mcode_patch(J, p, 0);
MSize len = T->szmcode;
MCode *px = exitstub_addr(J, exitno) - 6;
MCode *pe = p+len-6;
uint32_t stateaddr = u32ptr(&J2G(J)->vmstate);
if (len > 5 && p[len-5] == XI_JMP && p+len-6 + *(int32_t *)(p+len-4) == px)
*(int32_t *)(p+len-4) = jmprel(p+len, target);
/* Do not patch parent exit for a stack check. Skip beyond vmstate update. */
for (; p < pe; p++)
if (*(uint32_t *)(p+(LJ_64 ? 3 : 2)) == stateaddr && p[0] == XI_MOVmi) {
p += LJ_64 ? 11 : 10;
break;
}
lua_assert(p < pe);
for (; p < pe; p++) {
if ((*(uint16_t *)p & 0xf0ff) == 0x800f && p + *(int32_t *)(p+2) == px) {
*(int32_t *)(p+2) = jmprel(p+6, target);
p += 5;
}
}
lj_mcode_sync(T->mcode, T->mcode + T->szmcode);
lj_mcode_patch(J, mcarea, 1);
}