fix for zeroed-out 0xb leaf
Hypervisors may indicate x2APIC support but
sill have zeroes in the 0xb leaf. This patch
slightly improves behavior in such a case.
diff --git a/xbyak/xbyak_util.h b/xbyak/xbyak_util.h
index eefd152..4b3c9ba 100644
--- a/xbyak/xbyak_util.h
+++ b/xbyak/xbyak_util.h
@@ -146,6 +146,11 @@
numCores_[level - 1] = extractBit(data[1], 0, 15);
}
}
+ /*
+ Fallback values in case a hypervisor has 0xB leaf zeroed-out.
+ */
+ numCores_[SmtLevel - 1] = std::max(1u, numCores_[SmtLevel - 1]);
+ numCores_[CoreLevel - 1] = std::max(numCores_[SmtLevel - 1], numCores_[CoreLevel - 1]);
} else {
/*
Failed to deremine num of cores without x2APIC support.
