Intel® Architecture Instruction Set Extensions Programming Reference

Operation
PACKSSWB instruction (128-bit Legacy SSE version)
DEST[7:0] SaturateSignedWordToSignedByte (DEST[15:0]);
DEST[15:8] SaturateSignedWordToSignedByte (DEST[31:16]);
DEST[23:16] SaturateSignedWordToSignedByte (DEST[47:32]);
DEST[31:24] SaturateSignedWordToSignedByte (DEST[63:48]);
DEST[39:32] SaturateSignedWordToSignedByte (DEST[79:64]);
DEST[47:40] SaturateSignedWordToSignedByte (DEST[95:80]);
DEST[55:48] SaturateSignedWordToSignedByte (DEST[111:96]);
DEST[63:56] SaturateSignedWordToSignedByte (DEST[127:112]);
DEST[71:64] SaturateSignedWordToSignedByte (SRC[15:0]);
DEST[79:72] SaturateSignedWordToSignedByte (SRC[31:16]);
DEST[87:80] SaturateSignedWordToSignedByte (SRC[47:32]);
DEST[95:88] SaturateSignedWordToSignedByte (SRC[63:48]);
DEST[103:96] SaturateSignedWordToSignedByte (SRC[79:64]);
DEST[111:104] SaturateSignedWordToSignedByte (SRC[95:80]);
DEST[119:112] SaturateSignedWordToSignedByte (SRC[111:96]);
DEST[127:120] SaturateSignedWordToSignedByte (SRC[127:112]);
PACKSSDW instruction (128-bit Legacy SSE version)
DEST[15:0] SaturateSignedDwordToSignedWord (DEST[31:0]);
DEST[31:16] SaturateSignedDwordToSignedWord (DEST[63:32]);
DEST[47:32] SaturateSignedDwordToSignedWord (DEST[95:64]);
DEST[63:48] SaturateSignedDwordToSignedWord (DEST[127:96]);
DEST[79:64] SaturateSignedDwordToSignedWord (SRC[31:0]);
DEST[95:80] SaturateSignedDwordToSignedWord (SRC[63:32]);
DEST[111:96] SaturateSignedDwordToSignedWord (SRC[95:64]);
DEST[127:112] SaturateSignedDwordToSignedWord (SRC[127:96]);
VPACKSSWB instruction (VEX.128 encoded version)
DEST[7:0] SaturateSignedWordToSignedByte (SRC1[15:0]);
DEST[15:8] SaturateSignedWordToSignedByte (SRC1[31:16]);
DEST[23:16] SaturateSignedWordToSignedByte (SRC1[47:32]);
DEST[31:24] SaturateSignedWordToSignedByte (SRC1[63:48]);
DEST[39:32] SaturateSignedWordToSignedByte (SRC1[79:64]);
DEST[47:40] SaturateSignedWordToSignedByte (SRC1[95:80]);
DEST[55:48] SaturateSignedWordToSignedByte (SRC1[111:96]);
DEST[63:56] SaturateSignedWordToSignedByte (SRC1[127:112]);
DEST[71:64] SaturateSignedWordToSignedByte (SRC2[15:0]);
DEST[79:72] SaturateSignedWordToSignedByte (SRC2[31:16]);
DEST[87:80] SaturateSignedWordToSignedByte (SRC2[47:32]);
DEST[95:88] SaturateSignedWordToSignedByte (SRC2[63:48]);
DEST[103:96] SaturateSignedWordToSignedByte (SRC2[79:64]);
DEST[111:104] SaturateSignedWordToSignedByte (SRC2[95:80]);
DEST[119:112] SaturateSignedWordToSignedByte (SRC2[111:96]);
DEST[127:120] SaturateSignedWordToSignedByte (SRC2[127:112]);
DEST[VLMAX:128] 0;
VPACKSSDW instruction (VEX.128 encoded version)
DEST[15:0] SaturateSignedDwordToSignedWord (SRC1[31:0]);
DEST[31:16] SaturateSignedDwordToSignedWord (SRC1[63:32]);
DEST[47:32] SaturateSignedDwordToSignedWord (SRC1[95:64]);
DEST[63:48] SaturateSignedDwordToSignedWord (SRC1[127:96]);
INSTRUCTION SET REFERENCE
Ref. # 319433-014 5-17