fimf-arch-consistency,
Qimf-arch-consistency
Ensures that the math library functions
produce consistent results across different microarchitectural implementations
of the same architecture.
Syntax
Linux:
-fimf-arch-consistency
=
value
[
:
funclist
]
Windows:
/Qimf-arch-consistency
:
value
[
:
funclist
]
Arguments
- value
- Is one of the logical values "true" or "false".
- funclist
- Is an optional list of one or more math library functions to which the attribute should be applied. If you specify more than one function, they must be separated with commas.Precision-specific variants like sin and sinf are considered different functions, so you would need to use-fimf-arch-consistency=true:sin,sinf(or/Qimf-arch-consistency:true:sin,sinf) to specify consistent results for both the single-precision and double-precision sine functions.You also can specify the symbol /f to denote single-precision divides, symbol / to denote double-precision divides, symbol /l to denote extended-precision divides, and symbol /q to denote quad-precision divides. For example you can specify-fimf-arch-consistency=true:/or/Qimf-arch-consistency:true:/.
Default
- false
- Implementations of some math library functions may produce slightly different results on implementations of the same architecture.
Description
This option ensures that the math library functions produce consistent
results across different microarchitectural implementations of the same
architecture (for example, across different microarchitectural implementations
of IA-32 architecture). Consistency is only guaranteed for a single binary.
Consistency is not guaranteed across different architectures. For example,
consistency is not guaranteed across IA-32 architecture and Intel® 64
architecture.
If you need to define the accuracy for a math function of a certain
precision, specify the function name of the precision that you need. For
example:
Linux
If you want double precision, you can specify :sin; if you want single
precision, you can specify :sinf, as in
-fimf-arch-consistency=true:sin
or
-fimf-arch-consistency=false:sqrtf
.
Windows
If you want double precision, you can specify :sin; if you want single
precision, you can specify :sinf, as in
/Qimf-arch-consistency:true:sin
or
/Qimf-arch-consistency:false:sqrtf
.
If you do not specify any function names, then the setting applies to all
functions (and to all precisions). However, as soon as you specify an
individual function name, the setting applies only to the function of
corresponding precision. So, for example, sinf applies only to the
single-precision sine function, sin applies only to the double-precision sine
function, sinl applies only to the extended-precision sine function, etc.
The
-fimf-arch-consistency
(Linux*)
and
/Qimf-arch-consistency
(Windows*) option may decrease run-time
performance, but the option will provide bit-wise consistent results on all
Intel® processors and compatible, non-Intel processors, regardless of
micro-architecture. This option may not provide bit-wise consistent results
between different architectures.
Many routines in libraries LIBM (Math Library) and SVML (Short Vector Math
Library) are more highly optimized for Intel® microprocessors than for
non-Intel microprocessors.
This option only applies to host compilation. When
offloading is enabled, it does not impact device-specific compilation.
Product and Performance Information
|
|---|
Performance varies by use, configuration and other factors. Learn more at
www.Intel.com/PerformanceIndex.
Notice revision #20201201
|
IDE Equivalent
None
Alternate Options
None