2 Commits

Author	SHA1	Message	Date
Paul Mackerras	e08ca4ab8e	countzero: Add a register to help make timing ... This adds a register in the middle of the countzero computation, so that we now have two cycles to count leading or trailing zeroes instead of just one. Execute1 now outputs a one-cycle stall signal when it encounters a cntlz* or cnttz* instruction. With this, the countzero path no longer fails timing on the Artix-7 at 100MHz. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>	2020-01-14 22:45:05 +11:00
Paul Mackerras	4396eddc31	countzero: Add a testbench ... Signed-off-by: Paul Mackerras <paulus@ozlabs.org>	2019-10-14 08:43:38 +11:00