[clang] [HLSL] Don't invoke `dxv` from `clang-dxc` for text output (PR #135876)

[Damyan Pepper via cfe-commits]

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@@ -309,6 +309,9 @@ HLSLToolChain::TranslateArgs(const DerivedArgList &Args, StringRef BoundArch,
 }
 
 bool HLSLToolChain::requiresValidation(DerivedArgList &Args) const {
+  if (!Args.hasArg(options::OPT_dxc_Fo))
+    return false;
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damyanp wrote:

Doesn't this happen for most of our tests?  I thought we'd want validation to generally always be running?

https://github.com/llvm/llvm-project/pull/135876