Like is_contiguous, but more dynamic shape-friendly. Returns uncertain false instead of throwing 
data-dependent errors for tensors with unbacked sizes or strides that can be either contiguous or not.

The property is cached, meaning that if some runtime assertions are added that can be used to infer that the
 tensor is always contiguous after caching, this can still return false. 

This should be used in places where the contiguity check is not material or when there is a general path even
if less performant that  can be taken (for example, clone path in reshape or contiguous call).


[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]

…e c++ sym_is_contiguous"


When we compute contiguity for a tensor with dynamic shapes we first:
1) Try to compute it without guarding. 
2) If all shapes hinted, compute it with potentially adding guards. 
3) if any input is not hinted, compute it symbolically.

sym_is_contiguous return a SymBool that is then either evaluated or guard_or_false can be called
on it to avoid data dependent errors.  

ex:
 bool is_contiguous = input.sym_is_contiguous().guard_or_false(__FILE__, __LINE__);
is_contiguous_or_false is a helper function that does that. 
 
In this PR I only handle default contiguity, will follow up with changes for other formats like  channel_last .
We use this patter in this PR for several locations to avoid DDEs.
Differential Revision: [D77183032](https://our.internmc.facebook.com/intern/diff/D77183032)

cc jgong5 mingfeima XiaobingSuper sanchitintel ashokei jingxu10 jerryzh168 voznesenskym penguinwu EikanWang Guobing-Chen zhuhaozhe blzheng wenzhe-nrv jiayisunx ipiszy chenyang78 kadeng muchulee8 amjames chauhang aakhundov

[ghstack-poisoned]