Embed 64 bit constants directly in the IR, using two slots.

Contributed by Peter Cawley.

17 files changed, 105 insertions, 60 deletions

diff --git a/src/lj_asm.c b/src/lj_asm.c
index 9b394beb..0b3e770a 100644
--- a/src/lj_asm.c
+++ b/src/lj_asm.c
@@ -334,7 +334,7 @@ static Reg ra_rematk(ASMState *as, IRRef ref)
   RA_DBGX((as, "remat     $i $r", ir, r));
 #if !LJ_SOFTFP
   if (ir->o == IR_KNUM) {
-    emit_loadn(as, r, ir_knum(ir));
+    emit_loadk64(as, r, ir);
   } else
 #endif
   if (emit_canremat(REF_BASE) && ir->o == IR_BASE) {
@@ -695,15 +695,14 @@ static void ra_left(ASMState *as, Reg dest, IRRef lref)
   if (ra_noreg(left)) {
     if (irref_isk(lref)) {
       if (ir->o == IR_KNUM) {
-        cTValue *tv = ir_knum(ir);
         /* FP remat needs a load except for +0. Still better than eviction. */
-        if (tvispzero(tv) || !(as->freeset & RSET_FPR)) {
-          emit_loadn(as, dest, tv);
+        if (tvispzero(ir_knum(ir)) || !(as->freeset & RSET_FPR)) {
+          emit_loadk64(as, dest, ir);
           return;
         }
 #if LJ_64
       } else if (ir->o == IR_KINT64) {
-        emit_loadu64(as, dest, ir_kint64(ir)->u64);
+        emit_loadk64(as, dest, ir);
         return;
 #endif
       } else if (ir->o != IR_KPRI) {
@@ -1963,8 +1962,14 @@ static void asm_setup_regsp(ASMState *as)
   ra_setup(as);
 
   /* Clear reg/sp for constants. */
-  for (ir = IR(T->nk), lastir = IR(REF_BASE); ir < lastir; ir++)
+  for (ir = IR(T->nk), lastir = IR(REF_BASE); ir < lastir; ir++) {
     ir->prev = REGSP_INIT;
+    if (irt_is64(ir->t) && ir->o != IR_KNULL) {
+      /* Make life easier for backends by putting address of constant in i. */
+      ir->i = (int32_t)(intptr_t)(ir+1);
+      ir++;
+    }
+  }
 
   /* REF_BASE is used for implicit references to the BASE register. */
   lastir->prev = REGSP_HINT(RID_BASE);
diff --git a/src/lj_asm_x86.h b/src/lj_asm_x86.h
index 69d1256e..0361a965 100644
--- a/src/lj_asm_x86.h
+++ b/src/lj_asm_x86.h
@@ -306,6 +306,16 @@ static void asm_fusexref(ASMState *as, IRRef ref, RegSet allow)
   }
 }
 
+/* Fuse load of 64 bit IR constant into memory operand. */
+static Reg asm_fuseloadk64(ASMState *as, IRIns *ir)
+{
+  const uint64_t *k = &ir_k64(ir)->u64;
+  as->mrm.ofs = ptr2addr(k);
+  as->mrm.base = RID_NONE;
+  as->mrm.idx = RID_NONE;
+  return RID_MRM;
+}
+
 /* Fuse load into memory operand. */
 static Reg asm_fuseload(ASMState *as, IRRef ref, RegSet allow)
 {
@@ -325,19 +335,13 @@ static Reg asm_fuseload(ASMState *as, IRRef ref, RegSet allow)
   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;
-    }
+    if (!(avail & (avail-1)))  /* Fuse if less than two regs available. */
+      return asm_fuseloadk64(as, ir);
   } 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;
-    }
+    if (!(avail & (avail-1)))  /* Fuse if less than two regs available. */
+      return asm_fuseloadk64(as, ir);
   } else if (mayfuse(as, ref)) {
     RegSet xallow = (allow & RSET_GPR) ? allow : RSET_GPR;
     if (ir->o == IR_SLOAD) {
@@ -711,7 +715,7 @@ static void asm_conv(ASMState *as, IRIns *ir)
         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_rma(as, XO_MOVSD, bias, k);
       emit_mrm(as, XO_MOVD, dest, asm_fuseload(as, lref, RSET_GPR));
       return;
     } else {  /* Integer to FP conversion. */
diff --git a/src/lj_emit_arm.h b/src/lj_emit_arm.h
index 47fee5fc..dff9fac4 100644
--- a/src/lj_emit_arm.h
+++ b/src/lj_emit_arm.h
@@ -219,8 +219,9 @@ static void emit_lsptr(ASMState *as, ARMIns ai, Reg r, void *p)
 
 #if !LJ_SOFTFP
 /* Load a number constant into an FPR. */
-static void emit_loadn(ASMState *as, Reg r, cTValue *tv)
+static void emit_loadk64(ASMState *as, Reg r, IRIns *ir)
 {
+  cTValue *tv = ir_knum(ir);
   int32_t i;
   if ((as->flags & JIT_F_VFPV3) && !tv->u32.lo) {
     uint32_t hi = tv->u32.hi;
diff --git a/src/lj_emit_mips.h b/src/lj_emit_mips.h
index fdebe94b..29079ea3 100644
--- a/src/lj_emit_mips.h
+++ b/src/lj_emit_mips.h
@@ -112,8 +112,8 @@ static void emit_lsptr(ASMState *as, MIPSIns mi, Reg r, void *p, RegSet allow)
   emit_tsi(as, mi, r, base, i);
 }
 
-#define emit_loadn(as, r, tv) \
-  emit_lsptr(as, MIPSI_LDC1, ((r) & 31), (void *)(tv), RSET_GPR)
+#define emit_loadk64(as, r, ir) \
+  emit_lsptr(as, MIPSI_LDC1, ((r) & 31), (void *)&ir_knum((ir))->u64, RSET_GPR)
 
 /* Get/set global_State fields. */
 static void emit_lsglptr(ASMState *as, MIPSIns mi, Reg r, int32_t ofs)
diff --git a/src/lj_emit_ppc.h b/src/lj_emit_ppc.h
index 4eb933ea..5163012a 100644
--- a/src/lj_emit_ppc.h
+++ b/src/lj_emit_ppc.h
@@ -115,8 +115,8 @@ static void emit_lsptr(ASMState *as, PPCIns pi, Reg r, void *p, RegSet allow)
   emit_tai(as, pi, r, base, i);
 }
 
-#define emit_loadn(as, r, tv) \
-  emit_lsptr(as, PPCI_LFD, ((r) & 31), (void *)(tv), RSET_GPR)
+#define emit_loadk64(as, r, ir) \
+  emit_lsptr(as, PPCI_LFD, ((r) & 31), (void *)&ir_knum((ir))->u64, RSET_GPR)
 
 /* Get/set global_State fields. */
 static void emit_lsglptr(ASMState *as, PPCIns pi, Reg r, int32_t ofs)
diff --git a/src/lj_emit_x86.h b/src/lj_emit_x86.h
index cbaf4e85..3d6f13f4 100644
--- a/src/lj_emit_x86.h
+++ b/src/lj_emit_x86.h
@@ -313,13 +313,23 @@ static void emit_loadu64(ASMState *as, Reg r, uint64_t u64)
 }
 #endif
 
-/* movsd r, [&tv->n] / xorps r, r */
-static void emit_loadn(ASMState *as, Reg r, cTValue *tv)
+/* Load 64 bit IR constant into register. */
+static void emit_loadk64(ASMState *as, Reg r, IRIns *ir)
 {
-  if (tvispzero(tv))  /* Use xor only for +0. */
-    emit_rr(as, XO_XORPS, r, r);
-  else
-    emit_rma(as, XO_MOVSD, r, &tv->n);
+  const uint64_t *k = &ir_k64(ir)->u64;
+  if (rset_test(RSET_FPR, r)) {
+    if (*k == 0) {
+      emit_rr(as, XO_XORPS, r, r);
+    } else {
+      emit_rma(as, XO_MOVSD, r, k);
+    }
+  } else {
+    if (*k == 0) {
+      emit_rr(as, XO_ARITH(XOg_XOR), r, r);
+    } else {
+      emit_rma(as, XO_MOV, r | REX_64, k);
+    }
+  }
 }
 
 /* -- Emit control-flow instructions -------------------------------------- */
diff --git a/src/lj_gc.c b/src/lj_gc.c
index 53f1d974..7c707462 100644
--- a/src/lj_gc.c
+++ b/src/lj_gc.c
@@ -238,6 +238,8 @@ static void gc_traverse_trace(global_State *g, GCtrace *T)
     IRIns *ir = &T->ir[ref];
     if (ir->o == IR_KGC)
       gc_markobj(g, ir_kgc(ir));
+    if (irt_is64(ir->t) && ir->o != IR_KNULL)
+      ref++;
   }
   if (T->link) gc_marktrace(g, T->link);
   if (T->nextroot) gc_marktrace(g, T->nextroot);
diff --git a/src/lj_ir.c b/src/lj_ir.c
index acb39463..124d5791 100644
--- a/src/lj_ir.c
+++ b/src/lj_ir.c
@@ -91,7 +91,7 @@ static void lj_ir_growbot(jit_State *J)
   IRIns *baseir = J->irbuf + J->irbotlim;
   MSize szins = J->irtoplim - J->irbotlim;
   lua_assert(szins != 0);
-  lua_assert(J->cur.nk == J->irbotlim);
+  lua_assert(J->cur.nk == J->irbotlim || J->cur.nk-1 == J->irbotlim);
   if (J->cur.nins + (szins >> 1) < J->irtoplim) {
     /* More than half of the buffer is free on top: shift up by a quarter. */
     MSize ofs = szins >> 2;
@@ -173,6 +173,18 @@ static LJ_AINLINE IRRef ir_nextk(jit_State *J)
   return ref;
 }
 
+/* Get ref of next 64 bit IR constant and optionally grow IR.
+** Note: this may invalidate all IRIns *!
+*/
+static LJ_AINLINE IRRef ir_nextk64(jit_State *J)
+{
+  IRRef ref = J->cur.nk - 2;
+  lua_assert(J->state != LJ_TRACE_ASM);
+  if (LJ_UNLIKELY(ref < J->irbotlim)) lj_ir_growbot(J);
+  J->cur.nk = ref;
+  return ref;
+}
+
 /* Intern int32_t constant. */
 TRef LJ_FASTCALL lj_ir_kint(jit_State *J, int32_t k)
 {
@@ -266,19 +278,18 @@ TValue *lj_ir_k64_reserve(jit_State *J)
   return ir_k64_add(J, kp, 0);  /* Set to 0. Final value is set later. */
 }
 
-/* Intern 64 bit constant, given by its address. */
-TRef lj_ir_k64(jit_State *J, IROp op, cTValue *tv)
+/* Intern 64 bit constant, given by its 64 bit pattern. */
+TRef lj_ir_k64(jit_State *J, IROp op, uint64_t u64)
 {
   IRIns *ir, *cir = J->cur.ir;
   IRRef ref;
   IRType t = op == IR_KNUM ? IRT_NUM : IRT_I64;
   for (ref = J->chain[op]; ref; ref = cir[ref].prev)
-    if (ir_k64(&cir[ref]) == tv)
+    if (ir_k64(&cir[ref])->u64 == u64)
       goto found;
-  ref = ir_nextk(J);
+  ref = ir_nextk64(J);
   ir = IR(ref);
-  lua_assert(checkptrGC(tv));
-  setmref(ir->ptr, tv);
+  ir[1].tv.u64 = u64;
   ir->t.irt = t;
   ir->o = op;
   ir->prev = J->chain[op];
@@ -290,13 +301,13 @@ found:
 /* Intern FP constant, given by its 64 bit pattern. */
 TRef lj_ir_knum_u64(jit_State *J, uint64_t u64)
 {
-  return lj_ir_k64(J, IR_KNUM, lj_ir_k64_find(J, u64));
+  return lj_ir_k64(J, IR_KNUM, u64);
 }
 
 /* Intern 64 bit integer constant. */
 TRef lj_ir_kint64(jit_State *J, uint64_t u64)
 {
-  return lj_ir_k64(J, IR_KINT64, lj_ir_k64_find(J, u64));
+  return lj_ir_k64(J, IR_KINT64, u64);
 }
 
 /* Check whether a number is int and return it. -0 is NOT considered an int. */
@@ -367,7 +378,7 @@ TRef lj_ir_kptr_(jit_State *J, IROp op, void *ptr)
   IRRef ref;
   lua_assert((void *)(uintptr_t)u32ptr(ptr) == ptr);
   for (ref = J->chain[op]; ref; ref = cir[ref].prev)
-    if (mref(cir[ref].ptr, void) == ptr)
+    if (ir_kptr(&cir[ref]) == ptr)
       goto found;
   ref = ir_nextk(J);
   ir = IR(ref);
@@ -432,9 +443,8 @@ void lj_ir_kvalue(lua_State *L, TValue *tv, const IRIns *ir)
   case IR_KPRI: setpriV(tv, irt_toitype(ir->t)); break;
   case IR_KINT: setintV(tv, ir->i); break;
   case IR_KGC: setgcV(L, tv, ir_kgc(ir), irt_toitype(ir->t)); break;
-  case IR_KPTR: case IR_KKPTR: case IR_KNULL:
-    setlightudV(tv, mref(ir->ptr, void));
-    break;
+  case IR_KPTR: case IR_KKPTR: setlightudV(tv, ir_kptr(ir)); break;
+  case IR_KNULL: setlightudV(tv, NULL); break;
   case IR_KNUM: setnumV(tv, ir_knum(ir)->n); break;
 #if LJ_HASFFI
   case IR_KINT64: {
diff --git a/src/lj_ir.h b/src/lj_ir.h
index 8a655b64..03377ec1 100644
--- a/src/lj_ir.h
+++ b/src/lj_ir.h
@@ -522,7 +522,9 @@ typedef uint32_t TRef;
 ** +-------+-------+---+---+---+---+
 ** |  op1  |  op2  | t | o | r | s |
 ** +-------+-------+---+---+---+---+
-** |  op12/i/gco   |   ot  | prev  | (alternative fields in union)
+** |  op12/i/gco32 |   ot  | prev  | (alternative fields in union)
+** +-------+-------+---+---+---+---+
+** |  TValue/gco64                 | (2nd IR slot for 64 bit constants)
 ** +---------------+-------+-------+
 **        32           16      16
 **
@@ -550,8 +552,9 @@ typedef union IRIns {
     )
   };
   int32_t i;            /* 32 bit signed integer literal (overlaps op12). */
-  GCRef gcr;            /* GCobj constant (overlaps op12). */
-  MRef ptr;             /* Pointer constant (overlaps op12). */
+  GCRef gcr;            /* GCobj constant (overlaps op12 or entire slot). */
+  MRef ptr;             /* Pointer constant (overlaps op12 or entire slot). */
+  TValue tv;            /* TValue constant (overlaps entire slot). */
 } IRIns;
 
 /* TODO_GC64: major changes required. */
@@ -560,10 +563,10 @@ typedef union IRIns {
 #define ir_ktab(ir)     (gco2tab(ir_kgc((ir))))
 #define ir_kfunc(ir)    (gco2func(ir_kgc((ir))))
 #define ir_kcdata(ir)   (gco2cd(ir_kgc((ir))))
-#define ir_knum(ir)     check_exp((ir)->o == IR_KNUM, mref((ir)->ptr, cTValue))
-#define ir_kint64(ir)   check_exp((ir)->o == IR_KINT64, mref((ir)->ptr,cTValue))
+#define ir_knum(ir)     check_exp((ir)->o == IR_KNUM, &(ir)[1].tv)
+#define ir_kint64(ir)   check_exp((ir)->o == IR_KINT64, &(ir)[1].tv)
 #define ir_k64(ir) \
-  check_exp((ir)->o == IR_KNUM || (ir)->o == IR_KINT64, mref((ir)->ptr,cTValue))
+  check_exp((ir)->o == IR_KNUM || (ir)->o == IR_KINT64, &(ir)[1].tv)
 #define ir_kptr(ir) \
   check_exp((ir)->o == IR_KPTR || (ir)->o == IR_KKPTR, mref((ir)->ptr, void))
 
diff --git a/src/lj_iropt.h b/src/lj_iropt.h
index fdc5f0d2..219d391a 100644
--- a/src/lj_iropt.h
+++ b/src/lj_iropt.h
@@ -41,7 +41,7 @@ LJ_FUNC TRef lj_ir_ggfload(jit_State *J, IRType t, uintptr_t ofs);
 /* Interning of constants. */
 LJ_FUNC TRef LJ_FASTCALL lj_ir_kint(jit_State *J, int32_t k);
 LJ_FUNC void lj_ir_k64_freeall(jit_State *J);
-LJ_FUNC TRef lj_ir_k64(jit_State *J, IROp op, cTValue *tv);
+LJ_FUNC TRef lj_ir_k64(jit_State *J, IROp op, uint64_t u64);
 LJ_FUNC TValue *lj_ir_k64_reserve(jit_State *J);
 LJ_FUNC cTValue *lj_ir_k64_find(jit_State *J, uint64_t u64);
 LJ_FUNC TRef lj_ir_knum_u64(jit_State *J, uint64_t u64);
diff --git a/src/lj_jit.h b/src/lj_jit.h
index eafbc327..e9ab319e 100644
--- a/src/lj_jit.h
+++ b/src/lj_jit.h
@@ -355,8 +355,8 @@ enum {
 /* Fold state is used to fold instructions on-the-fly. */
 typedef struct FoldState {
   IRIns ins;            /* Currently emitted instruction. */
-  IRIns left;           /* Instruction referenced by left operand. */
-  IRIns right;          /* Instruction referenced by right operand. */
+  IRIns left[2];        /* Instruction referenced by left operand. */
+  IRIns right[2];       /* Instruction referenced by right operand. */
 } FoldState;
 
 /* JIT compiler state. */
diff --git a/src/lj_opt_fold.c b/src/lj_opt_fold.c
index c102f2db..73a368ed 100644
--- a/src/lj_opt_fold.c
+++ b/src/lj_opt_fold.c
@@ -136,8 +136,8 @@
 /* Some local macros to save typing. Undef'd at the end. */
 #define IR(ref)         (&J->cur.ir[(ref)])
 #define fins            (&J->fold.ins)
-#define fleft           (&J->fold.left)
-#define fright          (&J->fold.right)
+#define fleft           (J->fold.left)
+#define fright          (J->fold.right)
 #define knumleft        (ir_knum(fleft)->n)
 #define knumright       (ir_knum(fright)->n)
 
@@ -2393,10 +2393,14 @@ retry:
   if (fins->op1 >= J->cur.nk) {
     key += (uint32_t)IR(fins->op1)->o << 10;
     *fleft = *IR(fins->op1);
+    if (fins->op1 < REF_TRUE)
+      fleft[1] = IR(fins->op1)[1];
   }
   if (fins->op2 >= J->cur.nk) {
     key += (uint32_t)IR(fins->op2)->o;
     *fright = *IR(fins->op2);
+    if (fins->op2 < REF_TRUE)
+      fright[1] = IR(fins->op2)[1];
   } else {
     key += (fins->op2 & 0x3ffu);  /* Literal mask. Must include IRCONV_*MASK. */
   }
diff --git a/src/lj_opt_mem.c b/src/lj_opt_mem.c
index 5549b0d0..92ecbb48 100644
--- a/src/lj_opt_mem.c
+++ b/src/lj_opt_mem.c
@@ -22,8 +22,8 @@
 /* Some local macros to save typing. Undef'd at the end. */
 #define IR(ref)         (&J->cur.ir[(ref)])
 #define fins            (&J->fold.ins)
-#define fleft           (&J->fold.left)
-#define fright          (&J->fold.right)
+#define fleft           (J->fold.left)
+#define fright          (J->fold.right)
 
 /*
 ** Caveat #1: return value is not always a TRef -- only use with tref_ref().
diff --git a/src/lj_opt_sink.c b/src/lj_opt_sink.c
index 49e13784..1b775f2d 100644
--- a/src/lj_opt_sink.c
+++ b/src/lj_opt_sink.c
@@ -220,6 +220,8 @@ static void sink_sweep_ins(jit_State *J)
   for (ir = IR(J->cur.nk); ir < irbase; ir++) {
     irt_clearmark(ir->t);
     ir->prev = REGSP_INIT;
+    if (irt_is64(ir->t) && ir->o != IR_KNULL)
+      ir++;
   }
 }
 
diff --git a/src/lj_opt_split.c b/src/lj_opt_split.c
index 49c9ae47..19818660 100644
--- a/src/lj_opt_split.c
+++ b/src/lj_opt_split.c
@@ -354,6 +354,8 @@ static void split_ir(jit_State *J)
       ir->prev = ref;  /* Identity substitution for loword. */
       hisubst[ref] = 0;
     }
+    if (irt_is64(ir->t) && ir->o != IR_KNULL)
+      ref++;
   }
 
   /* Process old IR instructions. */
diff --git a/src/lj_record.c b/src/lj_record.c
index b5fb6649..3b754897 100644
--- a/src/lj_record.c
+++ b/src/lj_record.c
@@ -61,7 +61,10 @@ static void rec_check_ir(jit_State *J)
     case IRMref: lua_assert(op1 >= nk);
       lua_assert(i >= REF_BIAS ? op1 < i : op1 > i); break;
     case IRMlit: break;
-    case IRMcst: lua_assert(i < REF_BIAS); continue;
+    case IRMcst: lua_assert(i < REF_BIAS);
+      if (irt_is64(ir->t) && ir->o != IR_KNULL)
+        i++;
+      continue;
     }
     switch (irm_op2(mode)) {
     case IRMnone: lua_assert(op2 == 0); break;
diff --git a/src/lj_snap.c b/src/lj_snap.c
index 8638d9ed..6199b1f0 100644
--- a/src/lj_snap.c
+++ b/src/lj_snap.c
@@ -371,8 +371,8 @@ static TRef snap_replay_const(jit_State *J, IRIns *ir)
   case IR_KPRI: return TREF_PRI(irt_type(ir->t));
   case IR_KINT: return lj_ir_kint(J, ir->i);
   case IR_KGC: return lj_ir_kgc(J, ir_kgc(ir), irt_t(ir->t));
-  case IR_KNUM: return lj_ir_k64(J, IR_KNUM, ir_knum(ir));
-  case IR_KINT64: return lj_ir_k64(J, IR_KINT64, ir_kint64(ir));
+  case IR_KNUM: case IR_KINT64:
+    return lj_ir_k64(J, (IROp)ir->o, ir_k64(ir)->u64);
   case IR_KPTR: return lj_ir_kptr(J, ir_kptr(ir));  /* Continuation. */
   default: lua_assert(0); return TREF_NIL; break;
   }
@@ -555,8 +555,7 @@ void lj_snap_replay(jit_State *J, GCtrace *T)
                 if (irref_isk(irs->op2) && irref_isk((irs+1)->op2)) {
                   uint64_t k = (uint32_t)T->ir[irs->op2].i +
                                ((uint64_t)T->ir[(irs+1)->op2].i << 32);
-                  val = lj_ir_k64(J, t == IRT_I64 ? IR_KINT64 : IR_KNUM,
-                                  lj_ir_k64_find(J, k));
+                  val = lj_ir_k64(J, t == IRT_I64 ? IR_KINT64 : IR_KNUM, k);
                 } else {
                   val = emitir_raw(IRT(IR_HIOP, t), val,
                           snap_pref(J, T, map, nent, seen, (irs+1)->op2));
@@ -651,7 +650,7 @@ static void snap_restoredata(GCtrace *T, ExitState *ex,
   uint64_t tmp;
   if (irref_isk(ref)) {
     if (ir->o == IR_KNUM || ir->o == IR_KINT64) {
-      src = mref(ir->ptr, int32_t);
+      src = (int32_t *)&ir[1];
     } else if (sz == 8) {
       tmp = (uint64_t)(uint32_t)ir->i;
       src = (int32_t *)&tmp;