Intel 64 and IA-32 Architectures Software Developers Manual Volume 1, Basic Architecture

4-12 Vol. 1

DATA TYPES

4.6.2 128-Bit Packed SIMD Data Types

The 128-bit packed SIMD data types were introduced into the IA-32 architecture in

the SSE extensions and used with SSE2, SSE3 and SSSE3 extensions. They are oper-

ated on primarily in the 128-bit XMM registers and memory. The fundamental 128-bit

packed data types are packed bytes, packed words, packed doublewords, and packed

quadwords (see Figure 4-8). When performing SIMD operations on these funda-

mental data types in XMM registers, these data types are interpreted as containing

packed or scalar single-precision floating-point or double-precision floating-point

values, or as containing packed byte, word, doubleword, or quadword integer values.

Figure 4-8. 128-Bit Packed SIMD Data Types

0127

Packed Words

Packed Bytes

Packed Doublewords

Packed Word Integers

Packed Byte Integers

Packed Doubleword Integers

Fundamental 128-Bit Packed SIMD Data Types

128-Bit Packed Floating-Point and Integer Data Types

Packed Quadwords

0127

Packed Quadword Integers

Packed Single Precision

Floating Point

Packed Double Precision

Floating Point