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Date: Sun, 16 Oct 2011 04:19:14 +0200
From: "felix.matenaar@rwth-aachen" <felix.matenaar@rwth-aachen.de>
Subject: [Qemu-devel] Cooperative BBL execution due to binary translation
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To: qemu-devel@nongnu.org

Hi *,

I have the following question regarding qemu binary translation of
target-i386 (and maybe other targets):

As far as I understood the code, when a basic block is executed, there
is no event which can interrupt the execution until the bbl reaches its
end and the control flow is then back at qemu. Is this right? Stumbled
over this when asking me why basic blocks are sometimes divided even if
there is no branch in it.

If so, is the reason for this that some application like that could
cause timing problems:

c = get_executable_memory(1Gb)
set(c, OPCODE_NOP, sizeof c)
jmp_into c

Regards,
    Felix