HSUBPS (Packed Single-FP Horizontal Subtract)

Opcodes

Opcode/Instruction Op/En 64/32-bit Mode CPUID Feature Flag Description
F2 0F 7D /r HSUBPS xmm1, xmm2/m128 RM V/V SSE3 Horizontal subtract packed single-precision floating-point values from xmm2/m128 to xmm1.
VEX.NDS.128.F2.0F.WIG 7D /r VHSUBPS xmm1, xmm2, xmm3/m128 RVM V/V AVX Horizontal subtract packed single-precision floating-point values from xmm2 and xmm3/mem.
VEX.NDS.256.F2.0F.WIG 7D /r VHSUBPS ymm1, ymm2, ymm3/m256 RVM V/V AVX Horizontal subtract packed single-precision floating-point values from ymm2 and ymm3/mem.

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

Subtracts the single-precision floating-point value in the second dword of the destination operand from the first dword of the destination operand and stores the result in the first dword of the destination operand.

Subtracts the single-precision floating-point value in the fourth dword of the destination operand from the third dword of the destination operand and stores the result in the second dword of the destination operand.

Subtracts the single-precision floating-point value in the second dword of the source operand from the first dword of the source operand and stores the result in the third dword of the destination operand.

Subtracts the single-precision floating-point value in the fourth dword of the source operand from the third dword of the source operand and stores the result in the fourth dword of the destination operand.

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

See Figure 3-21 for HSUBPS; see Figure 3-22 for VHSUBPS.

Figure 3-21. HSUBPS—Packed Single-FP Horizontal Subtract

X7

X6

X5

X4

X3

X2

X1

X0

SRC1

Y7

Y6

Y5

Y4

Y3

Y2

Y1

Y0

SRC2

DEST

Y6-Y7

Y4-Y5

X6-X7

X4-X5

Y2-Y3

X2-X3

X0-X1

Figure 3-22. VHSUBPS operation

128-bit Legacy SSE version: The second source can be an XMM register or an 128-bit memory location. The desti-nation is not distinct from the first source XMM register and the upper bits (VLMAX-1:128) of the corresponding YMM register destination are unmodified.

VEX.128 encoded version: the first source operand is an XMM register or 128-bit memory location. The destination operand is an XMM register. The upper bits (VLMAX-1:128) of the corresponding YMM register destination are zeroed.

VEX.256 encoded version: The first source operand is a YMM register. The second source operand can be a YMM register or a 256-bit memory location. The destination operand is a YMM register.

Operation

HSUBPS (128-bit Legacy SSE version)

DEST[31:0] ← SRC1[31:0] - SRC1[63:32]
DEST[63:32] ← SRC1[95:64] - SRC1[127:96]
DEST[95:64] ← SRC2[31:0] - SRC2[63:32]
DEST[127:96] ← SRC2[95:64] - SRC2[127:96]
DEST[VLMAX-1:128] (Unmodified)

VHSUBPS (VEX.128 encoded version)

DEST[31:0] ← SRC1[31:0] - SRC1[63:32]
DEST[63:32] ← SRC1[95:64] - SRC1[127:96]
DEST[95:64] ← SRC2[31:0] - SRC2[63:32]
DEST[127:96] ← SRC2[95:64] - SRC2[127:96]
DEST[VLMAX-1:128] ← 0

VHSUBPS (VEX.256 encoded version)

DEST[31:0] ← SRC1[31:0] - SRC1[63:32]
DEST[63:32] ← SRC1[95:64] - SRC1[127:96]
DEST[95:64] ← SRC2[31:0] - SRC2[63:32]
DEST[127:96] ← SRC2[95:64] - SRC2[127:96]
DEST[159:128] ← SRC1[159:128] - SRC1[191:160]
DEST[191:160] ← SRC1[223:192] - SRC1[255:224]
DEST[223:192] ← SRC2[159:128] - SRC2[191:160]
DEST[255:224] ← SRC2[223:192] - SRC2[255:224]

Intel C/C++ Compiler Intrinsic Equivalent

HSUBPS:

__m128 _mm_hsub_ps(__m128 a, __m128 b);

VHSUBPS:

__m256 _mm256_hsub_ps (__m256 a, __m256 b);

Exceptions

When the source operand is a memory operand, the operand must be aligned on a 16-byte boundary or a general-protection exception (#GP) will be generated.

Numeric Exceptions

Overflow, Underflow, Invalid, Precision, Denormal.

Other Exceptions

See Exceptions Type 2.