Re: Question regarding EIP instruction pointer

[email protected] Fri, 30 Mar 2007 15:58:23 +0200
Newsgroups org.kernel.vger.linux-assembly
Message-ID <[email protected]>
On Fri, Mar 30, 2007 at 09:38:41AM -0400, A D wrote:

> I know that EIP register is the instruction pointer. But how does it
> know how many bytes it needs to increment to the next instruction?
In order to execute the current instruction, the CPU must determine its
format, which also means finding out how many bytes the command takes.

Next command is at eip+sizeof(command).  Of course, this only holds for
subsequent execution, branching is another thing.

  Leslie

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