[PATCH] Add preliminary Alpha support

Clang Frontend
1

Signed-off-by: Matt Turner <mattst88@gmail.com>

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Signed-off-by: Matt Turner <mattst88@gmail.com>
---
So LLVM's Alpha backend works, somewhat. It generates code that segfaults at
any optimization level except -O0, but this is a start at reviving it.

The patch looks good, but I haven't looked at clang stuff for quite a
while. Others can comment more here.

Things I'm unsure about:
DescriptionString - I think everything is natually aligned, but the MIPS
desc string I looked at specified 32-bit alignment for 8 and 16-bit units.

   getDefaultFeatures \- This seems to be where ISA additions should be created,
   or something, but I see &#39;FIXME: This should not be here\.&#39; in other arch&#39;s
   code\. So, what goes here?

If your assumption is correct, then probably nothing. I took 21164
support out a few years ago, so only 21264 features are supported.

   getTargetDefines \- I don&#39;t know what this function does\. Sets what the
   preprocessor is supposed to define? gcc defines \_\_alpha\_\_ and some other
   things dependent on features supported\. Should these things be defined here?

   getTargetBuiltins \- No idea what this is\.

I would assume things like:
__builtin_alpha_mskwh
__builtin_alpha_minub8

   validateAsmConstraint \- I think this is for validating inline assembly inputs
   and outputs? If so, this shouldn&#39;t be a problem\.

Yes. I think you should only need to check INT/FP ness to validate most asm.

   getClobbers \- Must be for inline assembly\. The only relevant comments I see
   in other code is &#39;// FIXME: Is this really right?&#39;, so not terribly helpful\.

There shouldn't be hidden clobbers, so this doesn't seem too bad.

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Thanks for the review. Since there don't seem to be any NAKs, can we
commit this and I'll send follow-up patches to fill out things like
validateAsmConstraint?

Thanks,
Matt

4

Feel free to commit this.

-Eli

5

Great. What do I have to do to get commit access?

Thanks,
Matt

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http://llvm.org/docs/DeveloperPolicy.html#commitaccess

  - Doug