Function `_mm_loadiwkey`

#[target_feature(enable = "kl")]
pub unsafe fn _mm_loadiwkey(control: u32, integrity_key: __m128i, key_lo: __m128i, key_hi: __m128i)

Load internal wrapping key (IWKey). The 32-bit unsigned integer control specifies IWKey's KeySource and whether backing up the key is permitted. IWKey's 256-bit encryption key is loaded from key_lo and key_hi.

control[0]: NoBackup bit. If set, the IWKey cannot be backed up.
control[1:4]: KeySource bits. These bits specify the encoding method of the IWKey. The only allowed values are 0 (AES GCM SIV wrapping algorithm with the specified key) and 1 (AES GCM SIV wrapping algorithm with random keys enforced by hardware). After calling _mm_loadiwkey with KeySource set to 1, software must check ZF to ensure that the key was loaded successfully. Using any other value may result in a General Protection Exception.
control[5:31]: Reserved for future use, must be set to 0.

Note that setting the NoBackup bit and using the KeySource value 1 requires hardware support. These permissions can be found by calling __cpuid(0x19) and checking the ECX[0:1] bits. Failing to follow these restrictions may result in a General Protection Exception.

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