KVM: x86: BSF and BSR emulation change register unnecassarily

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If the source of BSF and BSR is zero, the destination register should not
change. That is how real hardware behaves.  If we set the destination even with
the same value that we had before, we may clear bits [63:32] unnecassarily.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427719163-5429-4-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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Nadav Amit 2015-03-30 15:39:21 +03:00 • committed by Paolo Bonzini

parent 6fd8e12757

commit 900efe200e

1 changed files with 18 additions and 1 deletions

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arch/x86/kvm/emulate.c

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