optimized bound checking

This commit is contained in:
bellard 2002-07-13 15:55:38 +00:00
parent 264dbcfed2
commit 17cbb388d3

23
tcc.c
View File

@ -286,6 +286,8 @@ struct TCCState {
char/short stored in integer registers) */
#define VT_MUSTBOUND 0x0800 /* bound checking must be done before
dereferencing value */
#define VT_BOUNDED 0x8000 /* value is bounded. The address of the
bounding function call point is in vc */
#define VT_LVAL_BYTE 0x1000 /* lvalue is a byte */
#define VT_LVAL_SHORT 0x2000 /* lvalue is a short */
#define VT_LVAL_UNSIGNED 0x4000 /* lvalue is unsigned */
@ -2660,12 +2662,16 @@ void gbound(void)
vtop->r &= ~VT_MUSTBOUND;
/* if lvalue, then use checking code before dereferencing */
if (vtop->r & VT_LVAL) {
lval_type = vtop->r & (VT_LVAL_TYPE | VT_LVAL);
gaddrof();
vpushi(0);
gen_bounded_ptr_add1();
gen_bounded_ptr_add2(1);
vtop->r |= lval_type;
/* if not VT_BOUNDED value, then make one */
if (!(vtop->r & VT_BOUNDED)) {
lval_type = vtop->r & (VT_LVAL_TYPE | VT_LVAL);
gaddrof();
vpushi(0);
gen_bounded_ptr_add();
vtop->r |= lval_type;
}
/* then check for dereferencing */
gen_bounded_ptr_deref();
}
}
#endif
@ -3365,9 +3371,8 @@ void gen_op(int op)
vswap();
gen_op('-');
}
gen_bounded_ptr_add1();
gen_bounded_ptr_add2(0);
} else
gen_bounded_ptr_add();
} else
#endif
{
gen_opic(op);