In cpu_loop_exec_tb(), we decide whether to look for a TB with
exactly insns_left instructions in it using the condition
(!cpu->icount_extra && insns_left > 0 && insns_left < tb->icount)
The check for icount_extra == 0 is unnecessary, because we just set
insns_left = MIN(0xffff, cpu->icount_budget);
icount_extra = icount_budget - insns_left;
and so icount_extra can only be non-zero if icount_budget > 0xffff
and insns_left == 0xffff. But in that case insns_left >= tb->icount
because 0xffff is much larger than TCG_MAX_INSNS, so the condition
will be false anyway.
Remove the unnecessary check, and instead assert:
* that we are only going to execute a partial TB here if the
icount budget has run out (ie icount_extra == 0)
* that the number of insns we're going to execute does fit into
the CF_COUNT_MASK
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210725174405.24568-3-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
c8cf47a946