arch

Architecture Restrictions

Not available on Intel® 64 architecture targeting the Intel® Xeon Phi™ coprocessor x100 product family (formerly code name Knights Corner), on IA-32 architecture targeting Intel® Graphics Technology, or on Intel® 64 architecture targeting Intel® Graphics Technology

Syntax

Linux and OS X:

None

Windows:

/arch:code

Arguments

code

Indicates to the compiler a feature set that it may target, including which instruction sets it may generate. Many of the following descriptions refer to Intel® Streaming SIMD Extensions (Intel® SSE) and Supplemental Streaming SIMD Extensions (SSSE). Possible values are:

CORE-AVX2	May generate Intel® Advanced Vector Extensions 2 (Intel® AVX2), Intel® AVX, SSE4.2, SSE4.1, SSE3, SSE2, SSE, and SSSE3 instructions.
CORE-AVX-I	May generate Float-16 conversion instructions and the RDRND instruction, Intel® Advanced Vector Extensions (Intel® AVX), Intel® SSE4.2, SSE4.1, SSE3, SSE2, SSE, and SSSE3 instructions.
AVX	May generate Intel® Advanced Vector Extensions (Intel® AVX), Intel® SSE4.2, SSE4.1, SSE3, SSE2, SSE, and SSSE3 instructions.
SSE4.2	May generate Intel® SSE4.2, SSE4.1, SSE3, SSE2, SSE, and SSSE3 instructions.
SSE4.1	May generate Intel® SSE4.1, SSE3, SSE2, SSE, and SSSE3 instructions.
SSSE3	May generate SSSE3 instructions and Intel® SSE3, SSE2, and SSE instructions.
SSE3	May generate Intel® SSE3, SSE2, and SSE instructions.
SSE2	May generate Intel® SSE2 and SSE instructions.
SSE	This option has been deprecated; it is now the same as specifying IA32.
IA32	Generates x86/x87 generic code that is compatible with IA-32 architecture. Disables any default extended instruction settings, and any previously set extended instruction settings. It also disables all feature-specific optimizations and instructions. This value is only available on IA-32 architecture.

Default

SSE2	The compiler may generate Intel® SSE2 and SSE instructions.

Description

This option tells the compiler which features it may target, including which instruction sets it may generate.

Code generated with these options should execute on any compatible, non-Intel processor with support for the corresponding instruction set.

Options /arch and /Qx are mutually exclusive. If both are specified, the compiler uses the last one specified and generates a warning.

If you specify both the /Qax and /arch options, the compiler will not generate Intel-specific instructions.

IDE Equivalent

Visual Studio: Code Generation > Enable Enhanced Instruction Set

Eclipse: None

Xcode: None

Alternate Options

Linux and OS X: -m

Windows: None