slicc: support for local variable declarations in action blocks

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Submitter:	Tony Gutierrez
Repository:	gem5
Branch:	default
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Description

Changeset 10855:e73aade25474
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slicc: support for local variable declarations in action blocks

Testing Done

Can you give examples for how this will be used and why it's needed?

Brad Beckmann May 13, 2015, 5:01 p.m. (May 13, 2015, 5:01 p.m.)

I cannot provide the exact example, but one could imagine a situtation where an action wants to collect an integer count from multiple structures before deciding what message to enqueue. Using local variables avoids having to construct a very long conditional test and in general leads to cleaner code within actions.

Ship It!

I think it is not just enabling local variables for action blocks.  
My understanding is that this patch allows declaration of local 
variables without initialization.  My question is would you not 
know the initial value or some default value in each case.

Brad Beckmann May 19, 2015, 10:41 a.m. (May 19, 2015, 10:41 a.m.)

You could make that argument independent of SLICC, yet many programming languages allow such local variable declarations. This feature simply allows SLICC to do the same.

Brad Beckmann May 20, 2015, 11:56 a.m. (May 20, 2015, 11:56 a.m.)

On Tues, 5/19 Nilay wrote via email "I agree with you. But I think you can declare local variables even now, whether initialized or uninitialized. This change would prevent the warning from getting printed when the variable is not initialized. So, the patch description is misleading."

Would it help if we updated the patch description to say:

slicc: remove unitialized local variable warnings in action blocks

You have a pending review.

Review Board 2.0.15

This change has been marked as submitted.

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Status: Closed (submitted)