Fix SRet for thiscall in i686-pc-win32

[Timur Iskhodzhanov]

Hi Aaron, Anton,

Can you please review the attached patch?

With this patch and some Clang-only changes, all my llvm.org/PR13676
compatibility tests pass fine. That said, this is likely all we need
to do in LLVM to fix PR13676, at least to the best of my knowledge.

This patch substitutes r151123 by Aaron which I find wrong - the
incorrect expectations in test/CodeGen/X86/thiscall-struct-return.ll
led to a wrong solution, also the test used a wrong triple.

As I wrote my own test before realizing there is a test from r151123
[1], and I find my test to work with thiscall better (e.g. it uses
conventional method mangling rather that Itanium mangling and has
better/more expectations), I've decided to delete Aaron's test.

Please note that my recent commit r178291 makes sure that EAX has the
right value when we leave a thiscall method.

[1] it was passing regardless of initial
CCIfSubtarget<"isTargetWindows(), ..." change due to a wrong triple. I
later removed the CCIfSubtarget condition...

Anton,
Am I right that there's no thiscall in gcc/MinGW?
If there is, I can put CCIfSubtarget<"isTargetWindows()", ..." back.

Thanks,
Timur
-------------- next part --------------
A non-text attachment was scrubbed...
Name: bug_13676_llvm.patch
Type: application/octet-stream
Size: 4065 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20130328/4f7896da/attachment.obj>