Re: Length-Changing Prefixes problem with the x86 Backend

2008-07-25 Thread Agner Fog
On Thu, 26 Jun 2008 Uros wrote: >Please also add a runtime test that can be used to analyze the problem. I am a temporary guest on the gcc mailing list and I haven't seen your mail before. In case your problem hasn't been solved yet, I can inform you that I have a disassembler which puts comme

Re: Length-Changing Prefixes problem with the x86 Backend

2008-06-25 Thread Uros Bizjak
On Wed, Jun 25, 2008 at 11:11 PM, Nadav <[EMAIL PROTECTED]> wrote: > I came across a problem with the x86 backend of gcc (3.3 - 4.1). When I > compile code which access a lookup table of size 65536, gcc generates code > which uses 16bit opcodes. > > The intel architecture optimization guide warns

Length-Changing Prefixes problem with the x86 Backend

2008-06-25 Thread Nadav
Hello, I came across a problem with the x86 backend of gcc (3.3 - 4.1). When I compile code which access a lookup table of size 65536, gcc generates code which uses 16bit opcodes. The intel architecture optimization guide warns that 16bit opcodes should be avoided whenever possible due to Length