I use AES-NI in kernel code. The new AES instructions use XMM registers, and I want to make sure that switching from user mode to kernel and switching to user mode will keep the state of XMM registers.
The MSDN link reads:
On 64-bit versions of Windows, the operating system stores SSE registers through thread (and process) switches. As a result, 64-bit driver code can safely use floating point operations in any IRQL.
Is this a confirmation that I do not need to save the state of the registers when calling the kernel code?
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