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INSTRUCTION SET REFERENCE
CVTPI2PSPacked Signed INT32 to Packed Single-FP Conversion
(Continued)
Comments
This instruction behaves identically to original MMX instructions, in the presence of x87-FP
instructions:
Transition from x87-FP to MMX technology (TOS=0, FP valid bits set to all valid).
MMX instructions write ones (1s) to the exponent part of the corresponding x87-FP
register.
However, the use of a memory source operand with this instruction will not result in the above
transition from x87-FP to MMX technology.
Prioritizing for fault and assist behavior for CVTPI2PS is as follows:
Memory source
1.Invalid opcode (CR0.EM=1)
2.DNA (CR0.TS=1)
3.#SS or #GP, for limit violation
4.#PF, page fault
5.Streaming SIMD Extensions numeric fault (i.e., precision)
Register source
1.Invalid opcode (CR0.EM=1)
2.DNA (CR0.TS=1)
3.#MF, pending x87-FP fault signaled
4.After returning from #MF, x87-FP->MMX technology transition
5.Streaming SIMD Extensions numeric fault (i.e., precision)
