[Vm-dev] VM Maker: VMMaker.oscog-eem.1504.mcz
tim at rowledge.org
Wed Nov 4 00:27:25 UTC 2015
> On 03-11-2015, at 4:04 PM, Ryan Macnak <rmacnak at gmail.com> wrote:
> I don't think ARM or MIPS have an instruction that preserves the high bits in the destination register.
None (In ARMv5/6/7, no idea about MIPS. Is that even a thing these days) that preserve the high bits - all loads of halfwords of bytes extend (signed or not, your choice) but there is the delightfully odd MOVT that moves a 16bit constant into the top 16bis of the destination register and leaves the *bottom* 16 alone.
In ARMv8 nothing I can see. There’s about eleventytwo load forms though, so who can say with any certainty?
tim Rowledge; tim at rowledge.org; http://www.rowledge.org/tim
Useful random insult:- Put a lens in each ear and you've got a telescope.
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