On Mon, Mar 27, 2017 at 1:37 PM, Steffen Klassert
wrote:
> On Sat, Mar 25, 2017 at 07:41:17PM +0300, Alexey Dobriyan wrote:
>> After (no branches):
>>
>> movr8d,0x20
>> movrdx,0x
>> movesi,DWORD PTR [rsi+0x2c]
>> movecx,r8d
>> subcl
On Sat, Mar 25, 2017 at 07:41:17PM +0300, Alexey Dobriyan wrote:
> Current addr4_match() code has special test for /0 prefixes because of
> standard required undefined behaviour. However, it is possible to omit
> it on 64-bit because shifting can be done within a 64-bit register and
> then truncate
Current addr4_match() code has special test for /0 prefixes because of
standard required undefined behaviour. However, it is possible to omit
it on 64-bit because shifting can be done within a 64-bit register and
then truncated to the expected value (which is 0 mask).
Implicit truncation by htonl(
