Re: [Qemu-devel] [PATCH 5/5] target-sh4: improve shad instruction

2015-07-24 Thread Aurelien Jarno
On 2015-07-24 13:14, Aurelien Jarno wrote: > The SH4 shad instruction can shift in both direction, depending on the > sign of the shift. This is currently implemented using branches, which > is not really efficient and prevents the optimizer to do its job. In > practice it is often used with a cons

[Qemu-devel] [PATCH 5/5] target-sh4: improve shad instruction

2015-07-24 Thread Aurelien Jarno
The SH4 shad instruction can shift in both direction, depending on the sign of the shift. This is currently implemented using branches, which is not really efficient and prevents the optimizer to do its job. In practice it is often used with a constant loaded in a register just before. Simplify th