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Selecting the target CPU at compile time
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About trapping integer division-by-zero errors wit
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About trapping software floating-point division-by
Identification of software floating-point division
Software floating-point division-by-zero debugging
New language features of C99
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// comments in C99 and C90
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Hexadecimal floating-point numbers in C99
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__func__ predefined identifier in C99
inline functions in C99
long long data type in C99 and C90
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Additional <math.h> library functions in C99
Complex numbers in C99
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Extended integer types and functions in <inttyp
<fenv.h> floating-point environment access i
<stdio.h> snprintf family of functions in C9
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<wchar.h> wide character I/O functions in C9
How to prevent uninitialized data from being initi
Compiler Diagnostic Messages
Using the Inline and Embedded Assemblers of the AR
Compiler User Guide
Selecting the target CPU at compile time
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| Home > Compiler Coding Practices > Selecting the target CPU at compile time | |||
Each new version of the ARM architecture typically supports extra instructions, extra modes of operation, pipeline differences, and register renaming. You can often significantly improve the performance of your C or C++ code by selecting the appropriate target processor at compile time.
To specify a target processor at compile time:
Decide whether the compiled program is to run on a specific ARM architecture-based processor or on different ARM processors.
Obtain the name, or names, of the target processors recognized by the compiler using the following compiler command-line option:
--cpu=list
If the compiled program is to run on a specific ARM architecture-based processor, having obtained the name of the processor with the
--cpu=listoption, select the target processor using the--cpu=compiler command-line option. For example, to compile code to run on a Cortex-M3 processor:namearmcc --cpu=Cortex-M3 myprog.c
Alternatively, if the compiled program is to run on different ARM processors, choose the lowest common denominator architecture appropriate for the application and then specify that architecture in place of the processor name. For example, to compile code for processors supporting the ARMv6 architecture:
armcc --cpu=6 myprog.c
Selecting the target processor using the --cpu= command-line
option enables the compiler to make full use of instructions that
are supported by the processor, and also to perform processor-specific
optimizations such as instruction scheduling.name
--cpu=list lists all the processors and
architectures supported by the compiler.
See also- Reference
Compiler Reference:
| Copyright © 2007-2008, 2011-2012 ARM. All rights reserved. | ARM DUI 0375D |
| Non-Confidential | ID062912 |
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| Home > Compiler Coding Practices > Selecting the target CPU at compile time |
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