Re: [Qemu-devel] [V3 PATCH 00/14] target-ppc: VSX Stage 4

[Richard Henderson <rth@twiddle.net>]

On 12/04/2013 04:58 AM, Tom Musta wrote:
> This is the fourth and final series of patches that add emulation support
> to QEMU for the PowerPC Vector Scalar Extension (VSX).
> 
> This series adds the instructions that were newly introduced with Power ISA
> V2.07.  This includes 3 scalar load instructions, 2 scalar store instructions,
> 7 standard single precision scalar arithmetic instructions, 8 scalar single
> precision fused multiply/add instructions, two integer-to-single-precision
> conversion instructions and 3 vector logical instructions.
> 
> The single-precision scalar arithmetic instructions all interpret the most
> significant 64 bits of a VSR as a single precision floating point number
> stored in double precision format (similar to the standard PowerPC floating
> point single precision instructions).  Thus a common theme in the supporting
> code is rounding of an intermediate double-precision number to single 
> precision.
> 
> V2: (a) Changed the rounding to single precision to reuse the existing
> helper_frsp() routine.  (b) Re-implemented the fused multiply/add instructions
> to use float32_muladd instead of float64_muladd, which avoids subtle rounding
> errors.
> 
> V3: Re-implemented fused multiply/add (patch 0012/0014) per clarification 
> from Richard Henderson.
> 
> Tom Musta (14):
>   target-ppc: VSX Stage 4: Add VSX 2.07 Flag
>   target-ppc: VSX Stage 4: Refactor lxsdx
>   target-ppc: VSX Stage 4: Add lxsiwax, lxsiwzx and lxsspx
>   target-ppc: VSX Stage 4: Refactor stxsdx
>   target-ppc: VSX Stage 4: Add stxsiwx and stxsspx
>   target-ppc: VSX Stage 4: Add xsaddsp and xssubsp
>   target-ppc: VSX Stage 4: Add xsmulsp
>   target-ppc: VSX Stage 4: Add xsdivsp
>   target-ppc: VSX Stage 4: Add xsresp
>   target-ppc: VSX Stage 4: Add xssqrtsp
>   target-ppc: VSX Stage 4: add xsrsqrtesp
>   target-ppc: VSX Stage 4: Add Scalar SP Fused Multiply-Adds
>   target-ppc: VSX Stage 4: Add xscvsxdsp and xscvuxdsp
>   target-ppc: VSX Stage 4: Add xxleqv, xxlnand and xxlorc
> 
>  target-ppc/cpu.h            |    4 +-
>  target-ppc/fpu_helper.c     |  197 ++++++++++++++++++++++++++++---------------
>  target-ppc/helper.h         |   18 ++++
>  target-ppc/translate.c      |  110 ++++++++++++++++++------
>  target-ppc/translate_init.c |    2 +-
>  5 files changed, 236 insertions(+), 95 deletions(-)
> 

I think I've now reviewed the entire series, as I think that only the fma patch
was really outstanding.  It would be helpful if you'd copy any given
Reviewed-by into the patch description for subsequent rounds, if the patch is
unchanged.


r~