Intel 64 and IA-32 Architectures Software Developers Manual Volume 2B, Instruction Set Reference, N-Z

4-66 Vol. 2B
INSTRUCTION SET REFERENCE, N-Z
Operation
PCMPGTB instruction with 64-bit operands:
IF DEST[7:0] > SRC[7:0]
THEN DEST[7:0) ← FFH;
ELSE DEST[7:0] ← 0; FI;
(* Continue comparison of 2nd through 7th bytes in DEST and SRC *)
IF DEST[63:56] > SRC[63:56]
THEN DEST[63:56] ← FFH;
ELSE DEST[63:56] ← 0; FI;
PCMPGTB instruction with 128-bit operands:
IF DEST[7:0] > SRC[7:0]
THEN DEST[7:0) ← FFH;
ELSE DEST[7:0] ← 0; FI;
(* Continue comparison of 2nd through 15th bytes in DEST and SRC *)
IF DEST[63:56] > SRC[63:56]
THEN DEST[63:56] ← FFH;
ELSE DEST[63:56] ← 0; FI;
PCMPGTW instruction with 64-bit operands:
IF DEST[15:0] > SRC[15:0]
THEN DEST[15:0] ← FFFFH;
ELSE DEST[15:0] ← 0; FI;
(* Continue comparison of 2nd and 3rd words in DEST and SRC *)
IF DEST[63:48] > SRC[63:48]
THEN DEST[63:48] ← FFFFH;
ELSE DEST[63:48] ← 0; FI;
PCMPGTW instruction with 128-bit operands:
IF DEST[15:0] > SRC[15:0]
THEN DEST[15:0] ← FFFFH;
ELSE DEST[15:0] ← 0; FI;
(* Continue comparison of 2nd through 7th words in DEST and SRC *)
IF DEST[63:48] > SRC[63:48]
THEN DEST[63:48] ← FFFFH;
ELSE DEST[63:48] ← 0; FI;
PCMPGTD instruction with 64-bit operands:
IF DEST[31:0] > SRC[31:0]
THEN DEST[31:0] ← FFFFFFFFH;
ELSE DEST[31:0] ← 0; FI;
IF DEST[63:32] > SRC[63:32]
THEN DEST[63:32] ← FFFFFFFFH;
ELSE DEST[63:32] ← 0; FI;