I’m new to assembly, and it’s quite fun. Anyways I have one question…
cmpw cr7, %r29, %r8
Is that code the equivalent of if cr7 > %r29 and %r8?
I’m new to assembly, and it’s quite fun. Anyways I have one question… cmpw
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I’m new to assembly, and it’s quite fun. Anyways I have one question…
cmpw cr7, %r29, %r8
Is that code the equivalent of if cr7 > %r29 and %r8?
It compares r29 to r8 and places the result in cr7 I believe.
In other words:
cr7 = r29 – r8
After reading some PPC docs, it looks like cr (the comparison register), gets a coded value, representing less, greater, equal.
In other architectures, such as x86, there is no CR per se, but a group of flags, such as ZF, SF, and CF (zero, sign, and carry flags). Those are always set during arithmetic operations, such as subtraction. Hence a compare is basically the same as a subtract.