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VFPCLASSSH

Classifies the upper double-precision floating-point value of a 128-bit YMM register and stores the resulting classification in a general-purpose register.

The following table covers what the source and destinations can be.

DO NOT support LOCK

This instruction is only available when the processor is operating in 64-bit mode or compatibility mode. It requires the processor to support the AVX instruction set.

The destination register must be a 32-bit general-purpose register (r32). The result is an u32 value representing the classification of the floating-point operand according to the IEEE 754 standard. Ensure that the YMM register is properly initialized; otherwise, the classification will reflect the existing data in the upper 64 bits of the register.