Optimize memory consumption of constant propagation (onnx#530)

* Simplify recursion

Signed-off-by: Tung D. Le <[email protected]>

* Use plain type

Signed-off-by: Tung D. Le <[email protected]>

* Using template

Signed-off-by: Tung D. Le <[email protected]>

* Some special cases do not need computing access indices

Signed-off-by: Tung D. Le <[email protected]>

* revise

Signed-off-by: Tung D. Le <[email protected]>

* clang-format

Signed-off-by: Tung D. Le <[email protected]>

* Change function names

Signed-off-by: Tung D. Le <[email protected]>

* Edit comments

Signed-off-by: Tung D. Le <[email protected]>

* use reshape for unsqueeze

Signed-off-by: Tung D. Le <[email protected]>

* Manually allocate memory and use external files

Signed-off-by: Tung D. Le <[email protected]>

* comments

Signed-off-by: Tung D. Le <[email protected]>

* Undo cmake

Signed-off-by: Tung D. Le <[email protected]>

* use stdlib

Signed-off-by: Tung D. Le <[email protected]>

* format

Signed-off-by: Tung D. Le <[email protected]>

* Use double and int64_t in computation to avoid the precious loss

Signed-off-by: Tung D. Le <[email protected]>

* Minor changes

Signed-off-by: Tung D. Le <[email protected]>

* Simplify some code

Signed-off-by: Tung D. Le <[email protected]>

* Not using attribute in splitop

Signed-off-by: Tung D. Le <[email protected]>

* Revise checking dense constants

Signed-off-by: Tung D. Le <[email protected]>

* Remove all temporary files at the end of constprop

Signed-off-by: Tung D. Le <[email protected]>

* A flag to switch between using file and heap

Signed-off-by: Tung D. Le <[email protected]>

* Use memory only

Signed-off-by: Tung D. Le <[email protected]>

* Add comment

Signed-off-by: Tung D. Le <[email protected]>

* Explaination about the use of buffers

Signed-off-by: Tung D. Le <[email protected]>

* Clean up includes

Signed-off-by: Tung D. Le <[email protected]>

Co-authored-by: Kevin O'Brien <[email protected]>