Intel® C++ Compiler Classic Developer Guide and Reference

ID 767249
Date 12/16/2022
Public

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Document Table of Contents

Arithmetic Intrinsics

Intel® Streaming SIMD Extensions 2 (Intel® SSE2) intrinsics for integer arithmetic operations are listed in this topic. The prototypes for Intel® SSE2 intrinsics are in the emmintrin.h header file.

To use these intrinsics, include the immintrin.h file as follows:

#include <immintrin.h>

The results of each intrinsic operation are placed in registers. The information about what is placed in each register appears in the tables below, in the detailed explanation of each intrinsic. R, R0, R1, ..., R15 represent the registers in which results are placed.

Intrinsic Name

Operation

Corresponding
Intel® SSE2 Instruction

_mm_add_epi8

Addition

PADDB

_mm_add_epi16

Addition

PADDW

_mm_add_epi32

Addition

PADDD

_mm_add_si64

Addition

PADDQ

_mm_add_epi64

Addition

PADDQ

_mm_add_epi8

__m128i _mm_add_epi8(__m128i a, __m128i b);

Adds the 16 signed or unsigned 8-bit integers in a to the 16 signed or unsigned 8-bit integers in b.

R0

R1

...

R15

a0 + b0

a1 + b1;

...

a15 + b15

_mm_add_epi16

__m128i _mm_add_epi16(__m128i a, __m128i b);

Adds the eight signed or unsigned 16-bit integers in a to the eight signed or unsigned 16-bit integers in b.

R0

R1

...

R7

a0 + b0

a1 + b1

...

a7 + b7

_mm_add_epi32

__m128i _mm_add_epi32(__m128i a, __m128i b);

Adds the four signed or unsigned 32-bit integers in a to the four signed or unsigned 32-bit integers in b.

R0

R1

R2

R3

a0 + b0

a1 + b1

a2 + b2

a3 + b3

_mm_add_si64

__m64 _mm_add_si64(__m64 a, __m64 b);

Adds the signed or unsigned 64-bit integer a to the signed or unsigned 64-bit integer b.

R0

a + b

_mm_add_epi64

__m128i _mm_add_epi64(__m128i a, __m128i b);

Adds the two signed or unsigned 64-bit integers in a to the two signed or unsigned 64-bit integers in b.

R0

R1

a0 + b0

a1 + b1

_mm_adds_epi8

__m128i _mm_adds_epi8(__m128i a, __m128i b);

Adds the 16 signed 8-bit integers in a to the 16 signed 8-bit integers in b using saturating arithmetic.

R0

R1

...

R15

SignedSaturate (a0 + b0)

SignedSaturate (a1 + b1)

...

SignedSaturate (a15 + b15)

_mm_adds_epi16

__m128i _mm_adds_epi16(__m128i a, __m128i b);

Adds the eight signed 16-bit integers in a to the eight signed 16-bit integers in b using saturating arithmetic.

R0

R1

...

R7

SignedSaturate (a0 + b0)

SignedSaturate (a1 + b1)

...

SignedSaturate (a7 + b7)

_mm_adds_epu8

__m128i _mm_adds_epu8(__m128i a, __m128i b);

Adds the 16 unsigned 8-bit integers in a to the 16 unsigned 8-bit integers in b using saturating arithmetic.

R0

R1

...

R15

UnsignedSaturate (a0 + b0)

UnsignedSaturate (a1 + b1)

...

UnsignedSaturate (a15 + b15)

_mm_adds_epu16

__m128i _mm_adds_epu16(__m128i a, __m128i b);

Adds the eight unsigned 16-bit integers in a to the eight unsigned 16-bit integers in b using saturating arithmetic.

R0

R1

...

R7

UnsignedSaturate (a0 + b0)

UnsignedSaturate (a1 + b1)

...

UnsignedSaturate (a7 + b7)

_mm_avg_epu8

__m128i _mm_avg_epu8(__m128i a, __m128i b);

Computes the average of the 16 unsigned 8-bit integers in a and the 16 unsigned 8-bit integers in b and rounds.

R0

R1

...

R15

(a0 + b0) / 2

(a1 + b1) / 2

...

(a15 + b15) / 2

_mm_avg_epi16

__m128i _mm_avg_epu16(__m128i a, __m128i b);

Computes the average of the eight unsigned 16-bit integers in a and the eight unsigned 16-bit integers in b and rounds.

R0

R1

...

R7

(a0 + b0) / 2

(a1 + b1) / 2

...

(a7 + b7) / 2

_mm_madd_epi16

__m128i _mm_madd_epi16(__m128i a, __m128i b);

Multiplies the eight signed 16-bit integers from a by the eight signed 16-bit integers from b. Adds the signed 32-bit integer results pairwise and packs the four signed 32-bit integer results.

R0

R1

R2

R3

(a0 * b0) + (a1 * b1)

(a2 * b2) + (a3 * b3)

(a4 * b4) + (a5 * b5)

(a6 * b6) + (a7 * b7)

_mm_max_epi16

__m128i _mm_max_epi16(__m128i a, __m128i b);

Computes the pairwise maxima of the eight signed 16-bit integers from a and the eight signed 16-bit integers from b.

R0

R1

...

R7

max(a0, b0)

max(a1, b1)

...

max(a7, b7)

_mm_max_epu8

__m128i _mm_max_epu8(__m128i a, __m128i b);

Computes the pairwise maxima of the 16 unsigned 8-bit integers from a and the 16 unsigned 8-bit integers from b.

R0

R1

...

R15

max(a0, b0)

max(a1, b1)

...

max(a15, b15)

_mm_min_epi16

__m128i _mm_min_epi16(__m128i a, __m128i b);

Computes the pairwise minima of the eight signed 16-bit integers from a and the eight signed 16-bit integers from b.

R0

R1

...

R7

min(a0, b0)

min(a1, b1)

...

min(a7, b7)

_mm_min_epu8

__m128i _mm_min_epu8(__m128i a, __m128i b);

Computes the pairwise minima of the 16 unsigned 8-bit integers from a and the 16 unsigned 8-bit integers from b.

R0

R1

...

R15

min(a0, b0)

min(a1, b1)

...

min(a15, b15)

_mm_mulhi_epi16

__m128i _mm_mulhi_epi16(__m128i a, __m128i b);

Multiplies the eight signed 16-bit integers from a by the eight signed 16-bit integers from b. Packs the upper 16-bits of the eight signed 32-bit results.

R0

R1

...

R7

(a0 * b0)[31:16]

(a1 * b1)[31:16]

...

(a7 * b7)[31:16]

_mm_mulhi_epu16

__m128i _mm_mulhi_epu16(__m128i a, __m128i b);

Multiplies the eight unsigned 16-bit integers from a by the eight unsigned 16-bit integers from b. Packs the upper 16-bits of the eight unsigned 32-bit results.

R0

R1

...

R7

(a0 * b0)[31:16]

(a1 * b1)[31:16]

...

(a7 * b7)[31:16]

_mm_mullo_epi16

__m128i _mm_mullo_epi16(__m128i a, __m128i b);

Multiplies the eight signed or unsigned 16-bit integers from a by the eight signed or unsigned 16-bit integers from b. Packs the lower 16-bits of the eight signed or unsigned 32-bit results.

R0

R1

...

R7

(a0 * b0)[15:0]

(a1 * b1)[15:0]

...

(a7 * b7)[15:0]

_mm_mul_su32

__m64 _mm_mul_su32(__m64 a, __m64 b);

Multiplies the lower 32-bit integer from a by the lower 32-bit integer from b, and returns the 64-bit integer result.

R0

a0 * b0

_mm_mul_epu32

__m128i _mm_mul_epu32(__m128i a, __m128i b);

Multiplies two unsigned 32-bit integers from a by two unsigned 32-bit integers from b. Packs the two unsigned 64-bit integer results.

R0

R1

a0 * b0

a2 * b2

_mm_sad_epu8

__m128i _mm_sad_epu8(__m128i a, __m128i b);

Computes the absolute difference of the 16 unsigned 8-bit integers from a and the 16 unsigned 8-bit integers from b. Sums the upper eight differences and lower eight differences, and packs the resulting two unsigned 16-bit integers into the upper and lower 64-bit elements.

R0

R1 to R3

R4

R5 to R7

abs(a0 - b0) + abs(a1 - b1) +...+ abs(a7 - b7)

0x0

abs(a8 - b8) + abs(a9 - b9) +...+ abs(a15 - b15)

0x0

_mm_sub_epi8

__m128i _mm_sub_epi8(__m128i a, __m128i b);

Subtracts the 16 signed or unsigned 8-bit integers of b from the 16 signed or unsigned 8-bit integers of a.

R0

R1

...

R15

a0 - b0

a1 - b1

...

a15 - b15

_mm_sub_epi16

__m128i _mm_sub_epi16(__m128i a, __m128i b);

Subtracts the eight signed or unsigned 16-bit integers of b from the eight signed or unsigned 16-bit integers of a.

R0

R1

...

R7

a0 - b0

a1 - b1

...

a7 - b7

_mm_sub_epi32

__m128i _mm_sub_epi32(__m128i a, __m128i b);

Subtracts the four signed or unsigned 32-bit integers of b from the four signed or unsigned 32-bit integers of a.

R0

R1

R2

R3

a0 - b0

a1 - b1

a2 - b2

a3 - b3

_mm_sub_si64

__m64 _mm_sub_si64 (__m64 a, __m64 b);

Subtracts the signed or unsigned 64-bit integer b from the signed or unsigned 64-bit integer a.

R

a - b

_mm_sub_epi64

__m128i _mm_sub_epi64(__m128i a, __m128i b);

Subtracts the two signed or unsigned 64-bit integers in b from the two signed or unsigned 64-bit integers in a.

R0

R1

a0 - b0

a1 - b1

_mm_subs_epi8

__m128i _mm_subs_epi8(__m128i a, __m128i b);

Subtracts the 16 signed 8-bit integers of b from the 16 signed 8-bit integers of a using saturating arithmetic.

R0

R1

...

R15

SignedSaturate (a0 - b0)

SignedSaturate (a1 - b1)

...

SignedSaturate (a15 - b15)

_mm_subs_epi16

__m128i _mm_subs_epi16(__m128i a, __m128i b);

Subtracts the eight signed 16-bit integers of b from the eight signed 16-bit integers of a using saturating arithmetic.

R0

R1

...

R15

SignedSaturate (a0 - b0)

SignedSaturate (a1 - b1)

...

SignedSaturate (a7 - b7)

_mm_subs_epu8

__m128i _mm_subs_epu8(__m128i a, __m128i b);

Subtracts the 16 unsigned 8-bit integers of b from the 16 unsigned 8-bit integers of a using saturating arithmetic.

R0

R1

...

R15

UnsignedSaturate (a0 - b0)

UnsignedSaturate (a1 - b1)

...

UnsignedSaturate (a15 - b15)

_mm_subs_epu16

__m128i _mm_subs_epu16(__m128i a, __m128i b);

Subtracts the eight unsigned 16-bit integers of b from the eight unsigned 16-bit integers of a using saturating arithmetic.

R0

R1

...

R7

UnsignedSaturate (a0 - b0)

UnsignedSaturate (a1 - b1)

...

UnsignedSaturate (a7 - b7)