ARM: Add LJ_SOFTFP define. Add support for soft-float slot handling.

lib/dump.lua

@@ -320,6 +320,10 @@ local function printsnap(tr, snap)
       else
 	local m, ot, op1, op2 = traceir(tr, ref)
 	out:write(colorize(format("%04d", ref), band(ot, 31)))
+	if band(sn, 0x80000) ~= 0 then -- SNAP_SOFTFPNUM
+	  local m, ot, op1, op2 = traceir(tr, ref+1)
+	  out:write(colorize(format("/%04d", ref+1), band(ot, 31)))
+	end
       end
       out:write(band(sn, 0x10000) == 0 and " " or "|") -- SNAP_FRAME
     else

src/lj_arch.h

@@ -232,6 +232,8 @@
 #define LJ_HASFFI		1
 #endif
 
+#define LJ_SOFTFP		(!LJ_ARCH_HASFPU)
+
 #if LJ_ARCH_ENDIAN == LUAJIT_BE
 #define LJ_LE			0
 #define LJ_BE			1

src/lj_jit.h

@@ -143,6 +143,7 @@ typedef uint32_t SnapEntry;
 #define SNAP_FRAME		0x010000	/* Frame slot. */
 #define SNAP_CONT		0x020000	/* Continuation slot. */
 #define SNAP_NORESTORE		0x040000	/* No need to restore slot. */
+#define SNAP_SOFTFPNUM		0x080000	/* Soft-float number. */
 LJ_STATIC_ASSERT(SNAP_FRAME == TREF_FRAME);
 LJ_STATIC_ASSERT(SNAP_CONT == TREF_CONT);
 

src/lj_obj.h

@@ -786,18 +786,18 @@ static LJ_AINLINE void copyTV(lua_State *L, TValue *o1, const TValue *o2)
 
 /* -- Number to integer conversion ---------------------------------------- */
 
-#if !LJ_ARCH_HASFPU
+#if LJ_SOFTFP
 LJ_ASMF int32_t lj_vm_tobit(double x);
 #endif
 
 static LJ_AINLINE int32_t lj_num2bit(lua_Number n)
 {
-#if LJ_ARCH_HASFPU
+#if LJ_SOFTFP
+  return lj_vm_tobit(n);
+#else
   TValue o;
   o.n = n + 6755399441055744.0;  /* 2^52 + 2^51 */
   return (int32_t)o.u32.lo;
-#else
-  return lj_vm_tobit(n);
 #endif
 }
 

src/lj_snap.c

@@ -72,6 +72,8 @@ static MSize snapshot_slots(jit_State *J, SnapEntry *map, BCReg nslots)
 	    (ir->op2 & (IRSLOAD_READONLY|IRSLOAD_PARENT)) != IRSLOAD_PARENT)
 	  sn |= SNAP_NORESTORE;
       }
+      if (LJ_SOFTFP && !irref_isk(ref) && irt_isnum(ir->t))
+	sn |= SNAP_SOFTFPNUM;
       map[n++] = sn;
     }
   }
@@ -386,9 +388,11 @@ const BCIns *lj_snap_restore(jit_State *J, void *exptr)
 	rs = snap_renameref(T, snapno, ref, rs);
       if (ra_hasspill(regsp_spill(rs))) {  /* Restore from spill slot. */
 	int32_t *sps = &ex->spill[regsp_spill(rs)];
-	if (irt_isinteger(t)) {
+	if (LJ_SOFTFP && (sn & SNAP_SOFTFPNUM)) {
+	  o->u32.lo = (uint32_t)*sps;
+	} else if (irt_isinteger(t)) {
 	  setintV(o, *sps);
-	} else if (irt_isnum(t)) {
+	} else if (!LJ_SOFTFP && irt_isnum(t)) {
 	  o->u64 = *(uint64_t *)sps;
 #if LJ_64
 	} else if (irt_islightud(t)) {
@@ -403,13 +407,12 @@ const BCIns *lj_snap_restore(jit_State *J, void *exptr)
       } else {  /* Restore from register. */
 	Reg r = regsp_reg(rs);
 	lua_assert(ra_hasreg(r));
-	if (irt_isinteger(t)) {
+	if (LJ_SOFTFP && (sn & SNAP_SOFTFPNUM)) {
+	  o->u32.lo = (uint32_t)ex->gpr[r-RID_MIN_GPR];
+	} else if (irt_isinteger(t)) {
 	  setintV(o, (int32_t)ex->gpr[r-RID_MIN_GPR]);
-	} else if (irt_isnum(t)) {
-	  if (RID_NUM_FPR)
-	    setnumV(o, ex->fpr[r-RID_MIN_FPR]);
-	  else
-	    setnumV(o, *(double *)&ex->gpr[r-RID_MIN_GPR]);
+	} else if (!LJ_SOFTFP && irt_isnum(t)) {
+	  setnumV(o, ex->fpr[r-RID_MIN_FPR]);
 #if LJ_64
 	} else if (irt_islightud(t)) {
 	  /* 64 bit lightuserdata which may escape already has the tag bits. */
@@ -421,6 +424,14 @@ const BCIns *lj_snap_restore(jit_State *J, void *exptr)
 	  setitype(o, irt_toitype(t));
 	}
       }
+      if (LJ_SOFTFP && (sn & SNAP_SOFTFPNUM)) {
+	rs = (ir+1)->prev;
+	if (LJ_UNLIKELY(bloomtest(rfilt, ref+1)))
+	  rs = snap_renameref(T, snapno, ref+1, rs);
+	o->u32.hi = (ra_hasspill(regsp_spill(rs))) ?
+	    (uint32_t)*&ex->spill[regsp_spill(rs)] :
+	    (uint32_t)ex->gpr[regsp_reg(rs)-RID_MIN_GPR];
+      }
     }
   }
   switch (bc_op(*pc)) {