# [GT4Py] ITIR pass to replace invalid identifiers

###### tags: `cycle 18` <!-- Change to the current cycle number -->

- Shaped by: Edoardo
- Appetite (FTEs, weeks): 2
- Developers: <!-- Filled in at the betting table unless someone is specifically required here -->

## Problem
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The ITIR pass for Static Single Assignment (SSA) needs to generate unique identifiers. It currently uses the unicode symbol "ᐞ", to append a suffix for each unique access. This symbol will then appear in the ITIR, which will be parsed by different backends.
The problem is that this symbol is not available in the target language of some backends (e.g. C/C++).

Another source of the same problem could be that user-written code has valid identifiers in Python, but not in a backend.

## Appetite
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## Solution
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The proposal is to implement an ITIR pass that will replace all invalid symbols. At this aim, we should come up with a scheme that maps the invalid Python identifiers to a more common character set and reuse that pass across all backends.

## Rabbit holes
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## No-gos
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