john-terraspace
commented
5 years ago Hi,
Agreed, the string is basically converted into a 32bit number, in the 2nd case I assume the immediate value is small enough to be sign extended to allow the cmp. In the first the value must too great,
Not sure off-hand what “12345678” turns to .. but it would make sense to have a warning if the immediate data is too large.
From: exit2 notifications@github.com Sent: 22 March 2019 13:56 To: Terraspace/UASM UASM@noreply.github.com Cc: Subscribed subscribed@noreply.github.com Subject: [Terraspace/UASM] cmp qword ptr [64bitregister], "string" (#99)
If I use instruction like: cmp qword ptr [rax], "12345678" UASM doesn't compile it. I think it is correct, because such instruction doesn't exists.
cmp qword ptr [rax], "1234" UASM compile this instruction. But I think it will be better if compiler display warning (not error). Because I think if someone using such instruction it is 99% mistake and warning will be great. I am talking about use with string.
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If I use instruction like: cmp qword ptr [rax], "12345678" UASM doesn't compile it. I think it is correct, because such instruction doesn't exists.
cmp qword ptr [rax], "1234" UASM compile this instruction. But I think it will be better if compiler display warning (not error). Because I think if someone using such instruction it is 99% mistake and warning will be great. I am talking about use with string.