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Xsave

426 bytes added, 20:36, 12 August 2018
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To enumerate which components of the frame are enabled execute <code>cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx)</code>. Each component will have bit set to 1 in 64 bit mask <code>eax + ((uint64_t)edx << 32)</code> if enabled.
Current list of known components are is the following (numbers are the bit position):
* <code>0</code>: x87 floating point registers
* <code>9</code>: Protection Keys User registers
* <code>10</code>: Hardware Duty Cycling
 
Once the bit mask is obtained we have to walk over each bit set and call <code>cpuid_count(0xd, component, &eax, &ebx, &ecx, &edx)</code>, where <code>component</code> is the *bit* position we are interested in. In other words it should be from 0 to 10. The result of this call is sitting in <code>ebx</code> which represent offset of the component from the frame base address and <code>eax</code> which shows component size.

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