instructions which have no direct register usage.
Darwin 'as' accepts:
add $0, (%rax)
but rejects
mov $0, (%rax)
for example.
Given that, only accept suffix matches which match exactly one form. We still
need to emit nice diagnostics for failures...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103015 91177308-0d34-0410-b5e6-96231b3b80d8
- The idea is that when a match fails, we just try to match each of +'b', +'w',
+'l'. If exactly one matches, we assume this is a mnemonic prefix and accept
it. If all match, we assume it is width generic, and take the 'l' form.
- This would be a horrible hack, if it weren't so simple. Therefore it is an
elegant solution! Chris gets the credit for this particular elegant
solution. :)
- Next step to making this more robust is to have the X86 matcher generate the
mnemonic prefix information. Ideally we would also compute up-front exactly
which mnemonic to attempt to match, but this may require more custom code in
the matcher than is really worth it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103012 91177308-0d34-0410-b5e6-96231b3b80d8
