PMINUB—Minimum of Packed Unsigned Byte Integers

Opcode/Instruction Op/En 64/32 bit Mode Support CPUID Feature Flag Description

0F DA /r1

PMINUB mm1, mm2/m64

RM V/V SSE Compare unsigned byte integers in mm2/m64 and mm1 and returns minimum values.

66 0F DA /r

PMINUB xmm1, xmm2/m128

RM V/V SSE2 Compare unsigned byte integers in xmm2/m128 and xmm1 and returns minimum values.

VEX.NDS.128.66.0F.WIG DA /r

VPMINUB xmm1, xmm2, xmm3/m128

RVM V/V AVX Compare packed unsigned byte integers in xmm2 and xmm3/m128 and store packed minimum values in xmm1.

VEX.NDS.256.66.0F.WIG DA /r

VPMINUB ymm1, ymm2, ymm3/m256

RVM V/V AVX2 Compare packed unsigned byte integers in ymm2 and ymm3/m256 and store packed minimum values in ymm1.

NOTES:

1. See note in Section 2.4, “Instruction Exception Specification” in the Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 2A and Section 22.25.3, “Exception Conditions of Legacy SIMD Instructions Operating on MMX Registers” in the Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 3A.

Instruction Operand Encoding

Op/En Operand 1 Operand 2 Operand 3 Operand 4
RM ModRM:reg (r, w) ModRM:r/m (r) NA NA
RVM ModRM:reg (w) VEX.vvvv (r) ModRM:r/m (r) NA

Description

Performs a SIMD compare of the packed unsigned byte integers in the destination operand (first operand) and the source operand (second operand), and returns the minimum value for each pair of byte integers to the destination operand.

In 64-bit mode, using a REX prefix in the form of REX.R permits this instruction to access additional registers (XMM8-XMM15).

Legacy SSE version: The source operand can be an MMX technology register or a 64-bit memory location. The destination operand can be an MMX technology register.

128-bit Legacy SSE version: The first source and destination operands are XMM registers. The second source operand is an XMM register or a 128-bit memory location. Bits (VLMAX-1:128) of the corresponding YMM destina-tion register remain unchanged.

VEX.128 encoded version: The first source and destination operands are XMM registers. The second source operand is an XMM register or a 128-bit memory location. Bits (VLMAX-1:128) of the destination YMM register are zeroed.

VEX.256 encoded version: The second source operand can be an YMM register or a 256-bit memory location. The first source and destination operands are YMM registers.

Note: VEX.L must be 0, otherwise the instruction will #UD.

Operation

PMINUB (for 64-bit operands)

    IF DEST[7:0] < SRC[17:0] THEN
         DEST[7:0] ← DEST[7:0];
    ELSE
         DEST[7:0] ← SRC[7:0]; FI;
    (* Repeat operation for 2nd through 7th bytes in source and destination operands *)
    IF DEST[63:56] < SRC[63:56] THEN
         DEST[63:56] ← DEST[63:56];
    ELSE
         DEST[63:56] ← SRC[63:56]; FI;

PMINUB (for 128-bit operands)

    IF DEST[7:0] < SRC[17:0] THEN
         DEST[7:0] ← DEST[7:0];
    ELSE
         DEST[7:0] ← SRC[7:0]; FI;
    (* Repeat operation for 2nd through 15th bytes in source and destination operands *)
    IF DEST[127:120] < SRC[127:120] THEN
         DEST[127:120] ← DEST[127:120];
    ELSE
         DEST[127:120] ← SRC[127:120]; FI;

VPMINUB (VEX.128 encoded version)

VPMINUB instruction for 128-bit operands:
    IF SRC1[7:0] < SRC2[7:0] THEN
         DEST[7:0] ← SRC1[7:0];
    ELSE
         DEST[7:0] ← SRC2[7:0]; FI;
    (* Repeat operation for 2nd through 15th bytes in source and destination operands *)
    IF SRC1[127:120] < SRC2[127:120] THEN
         DEST[127:120] ← SRC1[127:120];
    ELSE
         DEST[127:120] ← SRC2[127:120]; FI;
DEST[VLMAX-1:128] ← 0

VPMINUB (VEX.256 encoded version)

VPMINUB instruction for 128-bit operands:
    IF SRC1[7:0] < SRC2[7:0] THEN
         DEST[7:0] ← SRC1[7:0];
    ELSE
         DEST[15:0] ← SRC2[7:0]; FI;
    (* Repeat operation for 2nd through 31st bytes in source and destination operands *)
    IF SRC1[255:248] < SRC2[255:248] THEN
         DEST[255:248] ← SRC1[255:248];
    ELSE
         DEST[255:248] ← SRC2[255:248]; FI;

Intel C/C++ Compiler Intrinsic Equivalent

PMINUB:

__m64 _m_min_pu8 (__m64 a, __m64 b)

(V)PMINUB:

__m128i _mm_min_epu8 ( __m128i a, __m128i b)

VPMINUB:

__m256i _mm256_min_epu8 ( __m256i a, __m256i b)

Flags Affected

None.

Numeric Exceptions

None.

Other Exceptions

See Exceptions Type 4; additionally

#UD If VEX.L = 1.