Combining Processor Optimization and Auto CPU Dispatch (IA-32 only)

The following table shows how to combine processor target and dispatch options to compile programs with different optimizations and exclusions. See Processor Legend below table.

Optimize exclusively for...	...without excluding...
Optimize exclusively for...	A	B	C	D	E	F
A	-tpp5	-tpp5	-tpp5	-tpp5	-tpp5	-tpp5
B	N-A	-tpp5 -xM	-tpp5	-tpp5 -xM	-tpp5 -xM	-tpp5 -xM
C	N-A	N-A	-tpp6 -xi	-tpp6 -xi	-tpp6 -xi	-tpp6 -xi
D	N-A	N-A	N-A	-tpp6 -xiM	-tpp6 -xiM	-tpp6 -xiM
E	N-A	N-A	N-A	N-A	-tpp6 -xK	-tpp6 -xK
F	N-A	N-A	N-A	N-A	N-A	-tpp7 -xW

Processor Legend

A - Intel® Pentium® processors
B - Intel Pentium processors with MMX(TM) technology
C - Intel Pentium Pro processors
D - Intel Pentium II processors
E - Intel Pentium III processors
F - Intel Pentium 4 processors, Intel® Xeon(TM) processors, and Intel® Pentium® M processors

Example

If you wanted your program to

Always require the MMX(TM) technology extensions
Use Pentium Pro processor extensions when the processor it is run on offers it
Not use them when it does not

use the following command line options:

prompt>icc -xM -axi prog.c

In this example, -xM restricts the application to running on Pentium processors with MMX(TM) technology or later processors. If you wanted the program to run on earlier generations of IA-32 processors as well, you would use the following command line:

prompt>icc -axiM prog.c

This compilation generates optimized code for processors that support both the i and M extensions, but the compiled program will run on any IA-32 processor.