Question about Gimple FE

[Diego Novillo]

On 04/02/15 11:59, xue yinsong wrote:
> I suppose our goal is to translate the dumped program back to
> the C source code (otherwise we can simply retain the gotos and
> labels since they are already `valid’ in C). In this case we have to
> convert the gotos back to if-elses and whiles. As long as
> CFG informations are given, it’s possible to get rid of these gotos.

Not quite. The output of the debug dumpers is not really meant to be fed 
back to the compiler. They are debug dumps only. They do not contain 
enough information for code generation or analysis.

Gimple needs a text form that can be manually or automatically 
generated. This form needs to represent the complete state of the IL 
needed to continue codegen/analysis/optimization.

Ideally, one would be able to generate gimple at any arbitrary point in 
the compilation pipeline, and also inject gimple at any arbitrary point. 
This way, we can generate tests that exercise exactly one pass in the 
compiler (which means, it should be able to execute exactly one analysis 
or transformation pass, but that's another issue).

Whether the debug dumpers end up using the gimple generation routines is 
another question. I think in the long term, it will make sense to have 
the debug dumpers generate output in the same syntax expected by the 
gimple parser, however.


Diego.