[clang] [HLSL] Emit lifetime.start before copy-in for inout parameters (PR #191917)

[Alexandre Isoard via cfe-commits]

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@@ -0,0 +1,36 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library -O3 -disable-llvm-passes -emit-llvm -finclude-default-header -o - %s | FileCheck %s
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isoard-amd wrote:

The problem is that we need `-O` > 1 to generate the lifetime intrinsics (see `CodeGenFunction.cpp` → `shouldEmitLifetimeMarkers`).

https://github.com/llvm/llvm-project/pull/191917