# PetscSSEIsEnabled
Determines if Intel Streaming SIMD Extensions (SSE) to the x86 instruction set can be used.  Some operating systems do not allow the use of these instructions despite hardware availability. 
## Synopsis
```
#include "petscsys.h" 
static PetscBool petsc_sse_local_is_untested  = PETSC_TRUE;
static PetscBool petsc_sse_enabled_local      = PETSC_FALSE;
static PetscBool petsc_sse_global_is_untested = PETSC_TRUE;
static PetscBool petsc_sse_enabled_global     = PETSC_FALSE;
PetscErrorCode   PetscSSEIsEnabled(MPI_Comm comm, PetscBool *lflag, PetscBool *gflag)
```
Collective


## Input Parameter

- ***comm -*** the MPI Communicator



## Output Parameters

- ***lflag -*** Local Flag:  `PETSC_TRUE` if enabled in this process
- ***gflag -*** Global Flag: `PETSC_TRUE` if enabled for all processes in comm



## Note
NULL can be specified for lflag or gflag if either of these values are not desired.


## Options Database Keys

- ***-disable_sse -*** Disable use of hand tuned Intel SSE implementations




## Level
developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/utils/sseenabled.c.html#PetscSSEIsEnabled">src/sys/utils/sseenabled.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/sys/utils/sseenabled.c)


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[Index of all manual pages](/docs/manualpages/singleindex.md)  
