>>>>> "Paolo" == Paolo Bonzini <bonz...@gnu.org> writes:
Paolo> These are all the !SHIFT_COUNT_TRUNCATED targets. For 4.5 I
Paolo> would like to improve our RTL canonicalization so that no
Paolo> out-of-range shifts are ever in the RTL representation.
Paolo> This in turn means that the description given by
Paolo> SHIFT_COUNT_TRUNCATED must be exact. Right now
Paolo> !SHIFT_COUNT_TRUNCATED means "I don't know", I want it to mean
Paolo> "it is never truncated".
Paolo> I would like to know whether for
Paolo> avr,bfin,cris,frv,h8300,pdp11,rs6000 (which define
Paolo> SHIFT_COUNT_TRUNCATED as 0) and for mcore,sh,vax (which do not
Paolo> define it at all) it is right that shift counts are never
Paolo> truncated.
For PDP11, shift counts are actually truncated to a signed 6-bit
value. Somewhat odd for a 16 bit machine but that's what the book
says.
paul
