Apparatus and method for right shifting packed quadwords and extracting packed doublewords

A method comprising:

• decoding an instruction;
• executing the decoded instruction, wherein executing the decoded instruction comprises:
• right-shifting first and second packed quadword data elements from first and second packed quadword data element locations, respectively, in the first source register by an amount specified in an immediate value or in a control value in a second source register, the right-shifting to generate first and second right-shifted quadwords, wherein each of the packed quadword data elements including a sign bit,
• shifting the sign bit into any bit positions exposed by the right-shifting of the first and second quadwords, and
• selecting 32 most significant bits of the first and second right-shifted quadwords, including the sign bit, to be written to 32 least significant bit regions of first and second quadword data element locations, respectively, of a destination register.

A machine-readable medium having program code stored thereon which, when executed by a machine, causes the machine to perform the operations of:

• decoding an instruction;
• executing the decoded instruction, wherein executing the decoded instruction comprises:
• right-shifting first and second packed quadword data elements from first and second packed quadword data element locations, respectively, in the first source register by an amount specified in an immediate value or in a control value in a second source register, the right-shifting to generate first and second right-shifted quadwords, wherein each of the packed quadword data elements including a sign bit,
• shifting the sign bit into any bit positions exposed by the right-shifting of the first and second quadwords, and
• selecting 32 most significant bits of the first and second right-shifted quadwords, including the sign bit, to be written to 32 least significant bit regions of first and second quadword data element locations, respectively, of a destination register.