OpcodeDispatcher: Fixes FEX's H0F3A table handling of REX.W #4241
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Most of this table ignores REX.W, but two encodings change behaviour based on REX.W. These two encodings are PEXTRD/PEXTRQ and PINSRD/PINSRQ. For every other instruction encoding, they will ignore REX.W, but FEX was requiring that they didn't have REX.W encoding. I had special cased this in the past by adding PALIGNR, but that didn't handle any of the other instructions. We can't just handle REX.W in the OpcodeDispatcher and remove the two special cased instructions because these vector operations also interact with instruction prefix 0x66 which changes the operating size to 16bit with regular instructions. So instead just generate all listings of instructions with REX.W being zero and one and install handlers in all cases.
We just want to ensure these instructions are decoded, the regular tests are ensuring that the behaviour is correct.
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lioncash
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Most of this table ignores REX.W, but two encodings change behaviour
based on REX.W. These two encodings are PEXTRD/PEXTRQ and PINSRD/PINSRQ.
For every other instruction encoding, they will ignore REX.W, but FEX
was requiring that they didn't have REX.W encoding. I had special cased
this in the past by adding PALIGNR, but that didn't handle any of the
other instructions.
We can't just handle REX.W in the OpcodeDispatcher and remove the two
special cased instructions because these vector operations also interact
with instruction prefix 0x66 which changes the operating size to 16bit
with regular instructions.
So instead just generate all listings of instructions with REX.W being
zero and one and install handlers in all cases.