Optimizes application performance for systems using IA-64 architecture.
Windows: Optimization > Optimize For Intel® Processor
Linux: None
Mac OS X: None
IA-64 architecture
Linux and Mac OS X: | None |
Windows: | /G2 /G2-p9000 |
None
/G2-p9000 |
Performance is optimized for Dual-Core Intel® Itanium® 2 processor 9000 series. |
These options optimize application performance for a particular Intel® processor or family of processors. The compiler generates code that takes advantage of features of IA-64 architecture.
Option |
Description |
|---|---|
G2 |
Optimizes for Intel® Itanium® 2 processors. |
G2-p9000 |
Optimizes for Dual-Core Intel® Itanium® 2 processor 9000 series. This option affects the order of the generated instructions, but the generated instructions are limited to Intel® Itanium® 2 processor instructions unless the program specifies and executes intrinsics specific to the Dual-Core Intel® Itanium® 2 processor 9000 series. |
The resulting executable is backwards compatible and generated code is optimized for specific processors. For example, code generated with /G2-p9000 will run correctly on single-core Itanium® 2 processors, but it might not run as fast as if it had been generated using /G2.
/G2 |
Linux: -mtune=itanium2 Mac OS X: None Windows: None |
/G2-p9000 |
Linux: -mtune=itanium2-p9000, -mcpu=itanium2-p9000 (-mcpu is a deprecated option) Mac OS X: None Windows: None |
In the following example, the compiled binary of the source program prog.f is optimized for the Dual-Core Intel® Itanium® 2 processor 9000 series by default. The same binary will also run on single-core Itanium® 2 processors (unless the program specifies and executes intrinsics specific to the Dual-Core Intel® Itanium® 2 processor 9000 series). All lines in the code example are equivalent.
ifort prog.f
ifort /G2-p9000 prog.f
In the following example, the compiled binary is optimized for single-core Itanium® 2 processors:
ifort /G2 prog.f