* Ricardo Neri <ricardo.neri-calde...@linux.intel.com> wrote: > On Thu, Nov 02, 2017 at 09:51:08AM +0100, Ingo Molnar wrote: > > > > * Ricardo Neri <ricardo.neri-calde...@linux.intel.com> wrote: > > > > > + /* > > > + * -EDOM means that we must ignore the address_offset. In such a case, > > > + * in 64-bit mode the effective address relative to the RIP of the > > > + * following instruction. > > > + */ > > > + if (*regoff == -EDOM) { > > > + if (user_64bit_mode(regs)) > > > + tmp = (long)regs->ip + insn->length; > > > + else > > > + tmp = 0; > > > + } else if (*regoff < 0) { > > > + return -EINVAL; > > > + } else { > > > + tmp = (long)regs_get_register(regs, *regoff); > > > + } > > > > > + else > > > + indx = (long)regs_get_register(regs, indx_offset); > > > > This and subsequent patches include a disgustly insane amount of type casts > > - why? > > > > For example here 'tmp' is 'long', while regs_get_register() returns > > 'unsigned long', but no type cast is necessary for that. > > > > > + ret = get_eff_addr_modrm(insn, regs, &addr_offset, > > > + &eff_addr); > > One of the goals of this series is to have the ability to compute 16-bit, > 32-bit > and 64-bit addresses. I put lost of casts, between signed and unsigned types, > between 64-bit and 32-bit and 16-bit casts. After seeing your comment I have > gone > through the code and I have removed most of the casts. Instead I will use > masks. > I will also inspect the resulting assembly code to make sure the arithmetic is > performed in the address size pertinent to each case.
Well, casts are probably fine when the goal is to zero out high bits - but the ones I quoted converted types of the same with. For register values it would also probably be cleaner to use the u8, u16, u32 and u64 types instead of char/short/int/long - this goes hand in hand with how the instructions are documented in the SDMs. Thanks, Ingo