[PATCH] D37448: Fix cast assertion on MS inline assembly with vector spills (PR34021)

[Reid Kleckner via Phabricator via cfe-commits]

rnk added a comment.

I think this is a reasonable stop-gap fix since the code isn't trying to return EAX:EDX or XMM0 from the inline asm blob. This affects any function that contains inline asm and returns a vector, which is potentially a lot of stuff.



================
Comment at: test/CodeGen/pr34021.c:2
+// RUN: %clang_cc1 -fms-extensions %s -triple=i686-unknown-unknown -emit-llvm -o -
+// RUN: %clang_cc1 -fms-extensions %s -triple=x86_64-unknown-unknown -emit-llvm -o -
+// REQUIRES: asserts
----------------
Please FileCheck the IR. We should see a pattern like this:
```
define <4 x float> @rep()
  %retval = alloca <4 x float>
  call i64 inlineasm sideeffect {{.*}}
  store {{.*}}, <4 x float>* %retval
  %v = load {{.*}}, <4 x float>* %res
  store <4 x float> %v, <4 x float>* %retval
  %rv = load <4 x float>* %retval
  ret <4 x float> %rv
```

That IR pattern makes it clear that the store of the asm output is immediately killed by the store of `res` to `retval`.


Repository:
  rL LLVM

https://reviews.llvm.org/D37448