Replace ref by literal

[hbrunie]

Replacing PsyIR Reference by PsyIR Literal when it is easy to do so.
Same file, same subroutine, or subroutine contained in module.
Build a param_table with symbol name and Literal, then go through psyir references and symbol_table array type shapes to look for ref with name contained in param_table.

Issues:

• it seems that initial value will always be a literal, is this expected behavior? If so I can remove a test raise error not triggered yet.
• I might have found a bug: `character(len=4), parameter :: x = "toto" is not parsed a a is_constant.

[arporter]

• it seems that initial value will always be a literal, is this expected behavior? If so I can remove a test raise error not triggered yet.

Thanks Hugo. I'm pretty sure we allow any PSyIR expression as an initial value?

[hbrunie]

• it seems that initial value will always be a literal, is this expected behavior? If so I can remove a test raise error not triggered yet.

Thanks Hugo. I'm pretty sure we allow any PSyIR expression as an initial value?

Thanks. I made a test showing the current limit of this MR with respect to non-literal initial value (for example a binary operation).

But I don't understand why
character (len=4), parameter :: x ="toto" does not make a constant symbol with initial_value being

[arporter]

But I don't understand why
character (len=4), parameter :: x ="toto" does not make a constant symbol with initial_value being

I think that's because we don't support the len=xxx specification on a character declaration.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.88%. Comparing base (2d1f953) to head (5387311).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2828   +/-   ##
=======================================
  Coverage   99.88%   99.88%           
=======================================
  Files         357      358    +1     
  Lines       49742    49806   +64     
=======================================
+ Hits        49686    49750   +64     
  Misses         56       56           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[hbrunie]

But I don't understand why
character (len=4), parameter :: x ="toto" does not make a constant symbol with initial_value being

I think that's because we don't support the len=xxx specification on a character declaration.

That's ok. I don't deal with "complex" right hand side for now. If this is not a Literal, the parameter is just ignored.