[clang] [SPIRV] Add -spirv option to DXC driver (PR #65989)

[Natalie Chouinard via cfe-commits]

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@@ -2,8 +2,8 @@
 
 // Supported targets
 //
-// RUN: %clang -target dxil-unknown-shadermodel6.2-pixel %s -S -o /dev/null 2>&1 | FileCheck --check-prefix=CHECK-VALID %s
-// RUN: %clang -target spirv-unknown-shadermodel6.2-library %s -S -o /dev/null 2>&1 | FileCheck --check-prefix=CHECK-VALID %s
+// RUN: %clang -target dxil-unknown-shadermodel6.2-compute %s -S -o /dev/null 2>&1 | FileCheck --allow-empty --check-prefix=CHECK-VALID %s
+// RUN: %clang -target spirv-unknown-shadermodel6.2-compute %s -S -o /dev/null 2>&1 | FileCheck --allow-empty --check-prefix=CHECK-VALID %s
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sudonatalie wrote:

Since we still have some unanswered questions about our triple requirements, I left the sys portion as-is for now and added a TODO and https://github.com/llvm/llvm-project/issues/70051 to track. If we want to require it to be `unkown` we should do that in a separate patch, but I don't think it would add value now.

https://github.com/llvm/llvm-project/pull/65989