Re: Avoiding paradoxical subregs

2014-01-18 Thread Paulo J. Matos
On 18/01/14 20:11, pins...@gmail.com wrote: On Jan 18, 2014, at 12:04 PM, "Paulo J. Matos" wrote: On 17/01/14 17:36, Eric Botcazou wrote: I am not implying that this is a GCC bug, unless you think WORD_REISTER_OPERATIONS should have avoided the creation of such paradoxical subreg. No, tha

Re: Avoiding paradoxical subregs

2014-01-18 Thread pinskia
> On Jan 18, 2014, at 12:04 PM, "Paulo J. Matos" wrote: > > On 17/01/14 17:36, Eric Botcazou wrote: >>> I am not implying that this is a GCC bug, unless you think >>> WORD_REISTER_OPERATIONS should have avoided the creation of such >>> paradoxical subreg. >> >> No, that's precisely the contrar

Re: Avoiding paradoxical subregs

2014-01-18 Thread Paulo J. Matos
On 17/01/14 17:36, Eric Botcazou wrote: I am not implying that this is a GCC bug, unless you think WORD_REGISTER_OPERATIONS should have avoided the creation of such paradoxical subreg. No, that's precisely the contrary, WORD_REGISTER_OPERATIONS tends to create paradoxical subregs. I might th

Re: Avoiding paradoxical subregs

2014-01-17 Thread Eric Botcazou
> I am not implying that this is a GCC bug, unless you think > WORD_REGISTER_OPERATIONS should have avoided the creation of such > paradoxical subreg. No, that's precisely the contrary, WORD_REGISTER_OPERATIONS tends to create paradoxical subregs. > What I was looking after was for a generic sol

RE: Avoiding paradoxical subregs

2014-01-17 Thread Paulo Matos
> -Original Message- > From: Eric Botcazou [mailto:ebotca...@adacore.com] > Sent: 17 January 2014 16:23 > To: Paulo Matos > Cc: gcc@gcc.gnu.org > Subject: Re: Avoiding paradoxical subregs > > > I can use canonicalize_comparison like s390 to remove the subreg, ho

Re: Avoiding paradoxical subregs

2014-01-17 Thread Eric Botcazou
> I can use canonicalize_comparison like s390 to remove the subreg, however > the question then becomes about how to avoid this in general. We cannot > allow a zero_extend to become a paradoxical subreg and then have the subreg > discarded. Most of our instructions are vector instructions which wil