#define NARROW_MAX_BACKPROP 100
#define NARROW_MAX_STACK 256
-/* Context used for narrowing of type conversions. */
-typedef struct NarrowConv {
- jit_State *J; /* JIT compiler state. */
- IRRef2 *sp; /* Current stack pointer. */
- IRRef2 *maxsp; /* Maximum stack pointer minus redzone. */
- int lim; /* Limit on the number of emitted conversions. */
- IRRef mode; /* Conversion mode (IRTOINT_*). */
- IRRef2 stack[NARROW_MAX_STACK]; /* Stack holding the stack-machine code. */
-} NarrowConv;
-
/* The stack machine has a 32 bit instruction format: [IROpT | IRRef1]
** The lower 16 bits hold a reference (or 0). The upper 16 bits hold
** the IR opcode + type or one of the following special opcodes:
NARROW_INT /* Push KINT ref. The next code holds an int32_t. */
};
+typedef uint32_t NarrowIns;
+
+#define NARROWINS(op, ref) (((op) << 16) + (ref))
+#define narrow_op(ins) ((IROpT)((ins) >> 16))
+#define narrow_ref(ins) ((IRRef1)(ins))
+
+/* Context used for narrowing of type conversions. */
+typedef struct NarrowConv {
+ jit_State *J; /* JIT compiler state. */
+ NarrowIns *sp; /* Current stack pointer. */
+ NarrowIns *maxsp; /* Maximum stack pointer minus redzone. */
+ int lim; /* Limit on the number of emitted conversions. */
+ IRRef mode; /* Conversion mode (IRTOINT_*). */
+ NarrowIns stack[NARROW_MAX_STACK]; /* Stack holding stack-machine code. */
+} NarrowConv;
+
/* Lookup a reference in the backpropagation cache. */
static IRRef narrow_bpc_get(jit_State *J, IRRef1 key, IRRef mode)
{
/* Check the easy cases first. */
if (ir->o == IR_TONUM) { /* Undo inverse conversion. */
- *nc->sp++ = IRREF2(ir->op1, NARROW_REF);
+ *nc->sp++ = NARROWINS(NARROW_REF, ir->op1);
return 0;
} else if (ir->o == IR_KNUM) { /* Narrow FP constant. */
lua_Number n = ir_knum(ir)->n;
if (nc->mode == IRTOINT_TOBIT) { /* Allows a wider range of constants. */
int64_t k64 = (int64_t)n;
if (n == cast_num(k64)) { /* Only if constant doesn't lose precision. */
- *nc->sp++ = IRREF2(0, NARROW_INT);
- *nc->sp++ = (IRRef2)k64; /* But always truncate to 32 bits. */
+ *nc->sp++ = NARROWINS(NARROW_INT, 0);
+ *nc->sp++ = (NarrowIns)k64; /* But always truncate to 32 bits. */
return 0;
}
} else {
int32_t k = lj_num2int(n);
if (n == cast_num(k)) { /* Only if constant is really an integer. */
- *nc->sp++ = IRREF2(0, NARROW_INT);
- *nc->sp++ = (IRRef2)k;
+ *nc->sp++ = NARROWINS(NARROW_INT, 0);
+ *nc->sp++ = (NarrowIns)k;
return 0;
}
}
for (cref = J->chain[fins->o]; cref > ref; cref = IR(cref)->prev)
if (IR(cref)->op1 == ref &&
irt_isguard(IR(cref)->t) >= irt_isguard(fins->t)) {
- *nc->sp++ = IRREF2(cref, NARROW_REF);
+ *nc->sp++ = NARROWINS(NARROW_REF, cref);
return 0; /* Already there, no additional conversion needed. */
}
mode = IRTOINT_CHECK; /* Inner conversions need a stronger check. */
bpref = narrow_bpc_get(nc->J, (IRRef1)ref, mode);
if (bpref) {
- *nc->sp++ = IRREF2(bpref, NARROW_REF);
+ *nc->sp++ = NARROWINS(NARROW_REF, bpref);
return 0;
}
if (++depth < NARROW_MAX_BACKPROP && nc->sp < nc->maxsp) {
- IRRef2 *savesp = nc->sp;
+ NarrowIns *savesp = nc->sp;
int count = narrow_conv_backprop(nc, ir->op1, depth);
count += narrow_conv_backprop(nc, ir->op2, depth);
if (count <= nc->lim) { /* Limit total number of conversions. */
- *nc->sp++ = IRREF2(ref, IRTI(ir->o));
+ *nc->sp++ = NARROWINS(IRTI(ir->o), ref);
return count;
}
nc->sp = savesp; /* Too many conversions, need to backtrack. */
}
/* Otherwise add a conversion. */
- *nc->sp++ = IRREF2(ref, NARROW_CONV);
+ *nc->sp++ = NARROWINS(NARROW_CONV, ref);
return 1;
}
IROpT guardot = irt_isguard(fins->t) ? IRTG(IR_ADDOV-IR_ADD, 0) : 0;
IROpT convot = fins->ot;
IRRef1 convop2 = fins->op2;
- IRRef2 *next = nc->stack; /* List of instructions from backpropagation. */
- IRRef2 *last = nc->sp;
- IRRef2 *sp = nc->stack; /* Recycle the stack to store operands. */
+ NarrowIns *next = nc->stack; /* List of instructions from backpropagation. */
+ NarrowIns *last = nc->sp;
+ NarrowIns *sp = nc->stack; /* Recycle the stack to store operands. */
while (next < last) { /* Simple stack machine to process the ins. list. */
- IRRef2 ref = *next++;
- IROpT op = ref >> 16;
+ NarrowIns ref = *next++;
+ IROpT op = narrow_op(ref);
if (op == NARROW_REF) {
*sp++ = ref;
} else if (op == NARROW_CONV) {
sp--;
/* Omit some overflow checks for array indexing. See comments above. */
if (mode == IRTOINT_INDEX) {
- if (next == last && irref_isk((IRRef1)sp[0]) &&
- (uint32_t)IR((IRRef1)sp[0])->i + 0x40000000 < 0x80000000)
+ if (next == last && irref_isk(narrow_ref(sp[0])) &&
+ (uint32_t)IR(narrow_ref(sp[0]))->i + 0x40000000 < 0x80000000)
guardot = 0;
else
mode = IRTOINT_CHECK; /* Otherwise cache a stronger check. */
}
sp[-1] = emitir(op+guardot, sp[-1], sp[0]);
- narrow_bpc_set(J, (IRRef1)ref, (IRRef1)sp[-1], mode); /* Add to cache. */
+ /* Add to cache. */
+ narrow_bpc_set(J, narrow_ref(ref), narrow_ref(sp[-1]), mode);
}
}
lua_assert(sp == nc->stack+1);