[clang] [llvm] Adding splitdouble HLSL function (PR #109331)

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,14 @@
+; RUN: opt -S -scalarizer -mtriple=spirv-vulkan-library %s 2>&1 | llc -verify-machineinstrs -O0 -mtriple=spirv-unknown-unknown -o - | FileCheck %s
+
+; SPIRV lowering for splitdouble should relly on the scalarizer.
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farzonl wrote:

This comment doesn't sound right. We don't currently use the scalarizer when targeting SPIRV. I don't understand why we would start for the split double case.

https://github.com/llvm/llvm-project/pull/109331