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Diffstat (limited to 'Build/source/libs/luajit/LuaJIT-src/src/lj_asm_x86.h')
-rw-r--r--Build/source/libs/luajit/LuaJIT-src/src/lj_asm_x86.h2634
1 files changed, 2634 insertions, 0 deletions
diff --git a/Build/source/libs/luajit/LuaJIT-src/src/lj_asm_x86.h b/Build/source/libs/luajit/LuaJIT-src/src/lj_asm_x86.h
new file mode 100644
index 00000000000..941d09192c2
--- /dev/null
+++ b/Build/source/libs/luajit/LuaJIT-src/src/lj_asm_x86.h
@@ -0,0 +1,2634 @@
+/*
+** x86/x64 IR assembler (SSA IR -> machine code).
+** Copyright (C) 2005-2015 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 (ir->o == IR_KINT64) {
+ RegSet avail = as->freeset & ~as->modset & RSET_GPR;
+ lua_assert(allow != RSET_EMPTY);
+ if (!(avail & (avail-1))) { /* Fuse if less than two regs available. */
+ as->mrm.ofs = ptr2addr(ir_kint64(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) && !irref_isk(ref) &&
+ (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_XNARGS(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_XNARGS(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) ? XO_MOVSD : 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) && !(ci->flags & CCI_CASTU64)) {
+ emit_x87op(as, XI_FPOP); /* Pop unused result from x87 st0. */
+ }
+}
+
+/* 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+LJ_FR2+bc_a(*((const BCIns *)pc - 1));
+ as->topslot -= (BCReg)delta;
+ if ((int32_t)as->topslot < 0) as->topslot = 0;
+ irt_setmark(IR(REF_BASE)->t); /* Children must not coalesce with BASE reg. */
+ 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);
+ 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);
+ }
+ 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 ? XO_CVTTSD2SI : XO_CVTTSS2SI;
+ 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) ? XO_MOVSD : 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);
+ 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));
+}
+
+static void asm_conv64(ASMState *as, IRIns *ir)
+{
+ if (irt_isfp(ir->t))
+ asm_conv_fp_int64(as, ir);
+ else
+ asm_conv_int64_fp(as, ir);
+}
+#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));
+}
+
+/* -- Memory references --------------------------------------------------- */
+
+/* Get pointer to TValue. */
+static void asm_tvptr(ASMState *as, Reg dest, IRRef ref)
+{
+ IRIns *ir = IR(ref);
+ if (irt_isnum(ir->t)) {
+ /* For numbers use the constant itself or a spill slot as a TValue. */
+ if (irref_isk(ref))
+ emit_loada(as, dest, ir_knum(ir));
+ else
+ emit_rmro(as, XO_LEA, dest|REX_64, RID_ESP, ra_spill(as, ir));
+ } else {
+ /* Otherwise use g->tmptv to hold the TValue. */
+ if (!irref_isk(ref)) {
+ Reg src = ra_alloc1(as, ref, rset_exclude(RSET_GPR, dest));
+ emit_movtomro(as, REX_64IR(ir, src), dest, 0);
+ } else if (!irt_ispri(ir->t)) {
+ emit_movmroi(as, dest, 0, ir->i);
+ }
+ if (!(LJ_64 && irt_islightud(ir->t)))
+ emit_movmroi(as, dest, 4, irt_toitype(ir->t));
+ emit_loada(as, dest, &J2G(as->J)->tmptv);
+ }
+}
+
+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);
+}
+
+/* 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, IROp merge)
+{
+ RegSet allow = RSET_GPR;
+ int destused = ra_used(ir);
+ 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) or load niltv. */
+ l_end = emit_label(as);
+ if (merge == IR_NE)
+ asm_guardcc(as, CC_E); /* XI_JMP is not found by lj_asm_patchexit. */
+ else if (destused)
+ 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 (merge == IR_EQ)
+ asm_guardcc(as, CC_E);
+ 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_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 = XO_MOVSD; 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);
+}
+
+#define asm_fload(as, ir) asm_fxload(as, ir)
+#define asm_xload(as, ir) asm_fxload(as, ir)
+
+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);
+ }
+ }
+}
+
+#define asm_fstore(as, ir) asm_fxstore(as, ir)
+#define asm_xstore(as, ir) asm_fxstore(as, ir)
+
+#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 : XO_MOVSD, 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, XO_MOVSD, 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_CVTTSD2SI, dest, base, ofs);
+ } else {
+ emit_rmro(as, irt_isnum(t) ? XO_MOVSD : 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 id = (CTypeID)IR(ir->op1)->i;
+ CTSize sz;
+ CTInfo info = lj_ctype_info(cts, id, &sz);
+ const CCallInfo *ci = &lj_ir_callinfo[IRCALL_lj_mem_newgco];
+ IRRef args[4];
+ lua_assert(sz != CTSIZE_INVALID || (ir->o == IR_CNEW && ir->op2 != REF_NIL));
+
+ 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);
+ } else if (ir->op2 != REF_NIL) { /* Create VLA/VLS/aligned cdata. */
+ ci = &lj_ir_callinfo[IRCALL_lj_cdata_newv];
+ args[0] = ASMREF_L; /* lua_State *L */
+ args[1] = ir->op1; /* CTypeID id */
+ args[2] = ir->op2; /* CTSize sz */
+ args[3] = ASMREF_TMP1; /* CTSize align */
+ asm_gencall(as, ci, args);
+ emit_loadi(as, ra_releasetmp(as, ASMREF_TMP1), (int32_t)ctype_align(info));
+ return;
+ }
+
+ /* 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)+(id<<16)));
+ emit_gri(as, XG_ARITHi(XOg_AND), RID_ECX, LJ_GC_WHITES);
+ emit_opgl(as, XO_MOVZXb, RID_ECX, gc.currentwhite);
+
+ args[0] = ASMREF_L; /* lua_State *L */
+ args[1] = ASMREF_TMP1; /* MSize size */
+ 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));
+ }
+}
+
+static void asm_fpmath(ASMState *as, IRIns *ir)
+{
+ IRFPMathOp fpm = (IRFPMathOp)ir->op2;
+ 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 && asm_fpjoin_pow(as, ir)) {
+ /* Rejoined to pow(). */
+ } else {
+ asm_callid(as, ir, IRCALL_lj_vm_floor + fpm);
+ }
+}
+
+#define asm_atan2(as, ir) asm_callid(as, ir, IRCALL_atan2)
+
+static void asm_ldexp(ASMState *as, IRIns *ir)
+{
+ 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, XO_MOVSD, dest, RID_ESP, ofs);
+ }
+ emit_rmro(as, XO_FSTPq, XOg_FSTPq, RID_ESP, ofs);
+ emit_x87op(as, XI_FPOP1);
+ emit_x87op(as, XI_FSCALE);
+ asm_x87load(as, ir->op1);
+ asm_x87load(as, ir->op2);
+}
+
+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);
+}
+
+static void asm_pow(ASMState *as, IRIns *ir)
+{
+#if LJ_64 && LJ_HASFFI
+ if (!irt_isnum(ir->t))
+ asm_callid(as, ir, irt_isi64(ir->t) ? IRCALL_lj_carith_powi64 :
+ IRCALL_lj_carith_powu64);
+ else
+#endif
+ asm_fppowi(as, ir);
+}
+
+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. */
+ MCode *p = as->mcp + ((LJ_64 && *as->mcp < XI_TESTb) ? 3 : 2);
+ if ((p[1] & 15) < 14) {
+ if ((p[1] & 15) >= 12) p[1] -= 4; /* L <->S, NL <-> NS */
+ as->flagmcp = NULL;
+ as->mcp = p;
+ } /* else: cannot transform LE/NLE to cc without use of OF. */
+ }
+ 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_sub(ASMState *as, IRIns *ir)
+{
+ 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);
+}
+
+static void asm_mul(ASMState *as, IRIns *ir)
+{
+ if (irt_isnum(ir->t))
+ asm_fparith(as, ir, XO_MULSD);
+ else
+ asm_intarith(as, ir, XOg_X_IMUL);
+}
+
+static void asm_div(ASMState *as, IRIns *ir)
+{
+#if LJ_64 && LJ_HASFFI
+ if (!irt_isnum(ir->t))
+ asm_callid(as, ir, irt_isi64(ir->t) ? IRCALL_lj_carith_divi64 :
+ IRCALL_lj_carith_divu64);
+ else
+#endif
+ asm_fparith(as, ir, XO_DIVSD);
+}
+
+static void asm_mod(ASMState *as, IRIns *ir)
+{
+#if LJ_64 && LJ_HASFFI
+ if (!irt_isint(ir->t))
+ asm_callid(as, ir, irt_isi64(ir->t) ? IRCALL_lj_carith_modi64 :
+ IRCALL_lj_carith_modu64);
+ else
+#endif
+ asm_callid(as, ir, IRCALL_lj_vm_modi);
+}
+
+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_neg(ASMState *as, IRIns *ir)
+{
+ if (irt_isnum(ir->t))
+ asm_fparith(as, ir, XO_XORPS);
+ else
+ asm_neg_not(as, ir, XOg_NEG);
+}
+
+#define asm_abs(as, ir) asm_fparith(as, ir, XO_ANDPS)
+
+static void asm_intmin_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_min(ASMState *as, IRIns *ir)
+{
+ if (irt_isnum(ir->t))
+ asm_fparith(as, ir, XO_MINSD);
+ else
+ asm_intmin_max(as, ir, CC_G);
+}
+
+static void asm_max(ASMState *as, IRIns *ir)
+{
+ if (irt_isnum(ir->t))
+ asm_fparith(as, ir, XO_MAXSD);
+ else
+ asm_intmin_max(as, ir, CC_L);
+}
+
+/* Note: don't use LEA for overflow-checking arithmetic! */
+#define asm_addov(as, ir) asm_intarith(as, ir, XOg_ADD)
+#define asm_subov(as, ir) asm_intarith(as, ir, XOg_SUB)
+#define asm_mulov(as, ir) asm_intarith(as, ir, XOg_X_IMUL)
+
+#define asm_bnot(as, ir) asm_neg_not(as, ir, XOg_NOT)
+
+static void asm_bswap(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);
+}
+
+#define asm_band(as, ir) asm_intarith(as, ir, XOg_AND)
+#define asm_bor(as, ir) asm_intarith(as, ir, XOg_OR)
+#define asm_bxor(as, ir) asm_intarith(as, ir, XOg_XOR)
+
+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.
+ */
+}
+
+#define asm_bshl(as, ir) asm_bitshift(as, ir, XOg_SHL)
+#define asm_bshr(as, ir) asm_bitshift(as, ir, XOg_SHR)
+#define asm_bsar(as, ir) asm_bitshift(as, ir, XOg_SAR)
+#define asm_brol(as, ir) asm_bitshift(as, ir, XOg_ROL)
+#define asm_bror(as, ir) asm_bitshift(as, ir, XOg_ROR)
+
+/* -- 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 = asm_compmap[ir->o];
+ 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);
+ }
+ }
+}
+
+#define asm_equal(as, ir) asm_comp(as, ir)
+
+#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. */
+ as->curins--; /* Always skip the CONV. */
+ if (usehi || uselo)
+ asm_conv64(as, ir);
+ 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
+}
+
+/* -- Profiling ----------------------------------------------------------- */
+
+static void asm_prof(ASMState *as, IRIns *ir)
+{
+ UNUSED(ir);
+ asm_guardcc(as, CC_NE);
+ emit_i8(as, HOOK_PROFILE);
+ emit_rma(as, XO_GROUP3b, XOg_TEST, &J2G(as->J)->hookmask);
+}
+
+/* -- 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, cur_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) || irt_ismarked(ir->t))
+ 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) || irt_ismarked(ir->t))
+ 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;
+ }
+}
+
+/* -- 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);
+}
+