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Re: delayed branches and zero overhead loops
Joern Rennecke wrote:
On Tue, Feb 13, 2007 at 04:11:52PM -0500, Frank Ch. Eigler wrote:
The decoder generator is fully automatic. If you represent decodable
bits without cheating, it will do a reasonable job.
I which that were the case. Try to generate the decoder for the attached
file; it warns about one alledged Decoder ambiguity for j_L_r_r [$RC-noilink]
versus j_L_r_r [$RC-ilink] . The values for $RC-ilink and $RC-noilink are
disjoint. I've also tried to use a decode-split on this problem, but to
no avail.
The problem is that RC-ilink and RC-noilink are operands. They do not
participate in insn decoding. If there are no other differences in the
fixed fields of the insns (it's hard to tell because of the complexity
of your pmacros), then there will be an ambiguity. If you add enough
"-v"s to CGENFLAGS when you run your make, you will get a dump of the
pmacro-expanded input.
Dave