1.6.2 (additional use for d0,d1,d2), and Appendix D (Opcode Maps).
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-ditto. TODO.
+ditto. done 1.6.2 (FRS)
-missed the addition to 1.6.1.6 (DX-Form). TODO
+missed the addition to 1.6.1.6 (DX-Form). done
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3. Does the last line of the Summary apply to both instructions or just to
That doesn't actually clear FRT to zero because `NaN - NaN` and
`Inf - Inf` both equal `NaN`, not zero. Also, with "round to -inf",
0 - 0 produces -0, not 0. Thus use of `fsub` is critically
-dependent on the contents of registers and status flags, where
-`flis` is not.
+dependent on the contents of registers and status flags, and
+would require more instructions, where `flis` is not.
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5. "FRS" for both instructions should be changed to "FRT". ("FRS" normally
consistent with this usage.
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-acknowledged. TODO.
+acknowledged. done.
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8. More generally, the style of the verbal description for both instructions