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NEON instructions for fixed-point arithemtics

mszabc

Hi,

I'm somehow familiar with NEON, but it's the first time I'm trying to get serious advantage from it. I have fixed-point code which does very best from armv7 ISA. In particular it uses instructions such as SMMUL (writes top 32 bits of 64bit result to destination register) for fixed-point operations like Q31*Q31->Q31. I've seen articles about "fixed-point neon" here and there, but seems like they shall be rather named "integer NEON" because they all show VMUL which writes bottom 32bits to destination registers. it can't be used for Q31 multiplies, unless I would scale them by 16bits first. Is there any neon instruction which writes top 32 bits to registers in destination lane?

thanks

Michal