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C6x patch: Fix SPKERNEL assembly/disassembly

Joseph S. Myers joseph@codesourcery.com
Wed Oct 6 19:51:00 GMT 2010 
On Wed, 6 Oct 2010, Bernd Schmidt wrote:

> We don't handle the encoding of the SPKERNEL instruction correctly.  The
> fstg field grows from the high bits, i.e. it is bit-reversed.  The
> following patch corrects it in gas and objdump.
> 
> I've verified the two new tests against the TI assembler/disassembler.
> Interestingly all the existing ones pass before and after the patch.

This is OK.  The reason that the existing tests pass (I did verify 
diassembly of all the positive tests with the TI disassembler when doing 
the original port, as a sanity check for mistakes in the encodings listed 
in the ISA manuals) is that what I was thinking of testing was the 
boundary cases of largest/smallest field values accepted, meaning that all 
those tests are of values with all fstg bits set, i.e. unaffected by the 
reversal (and I didn't notice the table in the manual showing the 
reversal).

-- 
Joseph S. Myers
joseph@codesourcery.com
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