[compiler-rt] [llvm] [cmake] Refactor DIA SDK detection into FindDIASDK module (PR #160354)

[Saleem Abdulrasool via llvm-commits]

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@@ -0,0 +1,74 @@
+# Finds the Microsoft DIA SDK and sets DIASDK_FOUND and related variables.
+#
+# This module is intended to be used both internally by LLVM's build system and
+# by consuming projects when loading LLVMConfig.cmake.
+#
+# LLVM_WINSYSROOT may be set for locating the DIA SDK.
+#
+# If successful, the following variables will be defined:
+#   DIASDK_FOUND
+#   DIASDK_INCLUDE_DIR
+#   DIASDK_LIBRARIES
+#
+# Additionally, the following import target will be defined:
+#   DIASDK::Diaguids
+
+if(NOT WIN32)
+  set(DIASDK_FOUND FALSE)
+  return()
+endif()
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compnerd wrote:

I don't think that conditional on `MSVC` is correct, this is not dependent on the MSVC generator nor the MSVC compiler, but rather if we are building for Windows. That said, the guard here is just avoid the unnecessary stats, which is a nice touch.

https://github.com/llvm/llvm-project/pull/160354