[GLUTEN-7866][CH] Fallback for unsupported regex in re2

[exmy]

What changes were proposed in this pull request?

(Fixes: #7866)

How was this patch tested?

add ut

[github-actions]

#7866

[github-actions]

Run Gluten Clickhouse CI on x86

[github-actions]

Run Gluten Clickhouse CI on x86

[PHILO-HE]

@exmy, I'm not familiar with CH backend code. In velox backend, we have a validation function on native side (see below link). In its implementation, RE2 tries to compile literal regex pattern, and then some known unsupported or incompatible cases are filter out even though compiling can pass. Can this handling be a reference to you to fix your issues?

https://github.com/apache/incubator-gluten/blob/main/cpp/velox/utils/Common.cc#L55

[exmy]

@exmy, I'm not familiar with CH backend code. In velox backend, we have a validation function on native side (see below link). In its implementation, RE2 tries to compile literal regex pattern, and then some known unsupported or incompatible cases are filter out even though compiling can pass. Can this handling be a reference to you to fix your issues?

https://github.com/apache/incubator-gluten/blob/main/cpp/velox/utils/Common.cc#L55

Thanks for advice! It's indeed a better way to validate on native side, but ch backend currently does not support it. Maybe this way wil be adopted later as well.

BTW, I noticed it seems missing validate for split expression in https://github.com/apache/incubator-gluten/blob/main/cpp/velox/substrait/SubstraitToVeloxPlanValidator.cc#L56. The second parameter for split is also a regex string.

[PHILO-HE]

BTW, I noticed it seems missing validate for split expression in https://github.com/apache/incubator-gluten/blob/main/cpp/velox/substrait/SubstraitToVeloxPlanValidator.cc#L56. The second parameter for split is also a regex string.

@exmy, thanks for letting me know this! Currently, this function's implementation is not fully ready in Velox. I have created an issue to track this: #7872.