[llvm] [DXIL][Analysis] Collect Function properties in Metadata Analysis (PR #105728)

[Justin Bogner via llvm-commits]

================
@@ -33,15 +38,54 @@ static ModuleMetadataInfo collectMetadataInfo(Module &M) {
     MMDAI.ValidatorVersion =
         VersionTuple(MajorMD->getZExtValue(), MinorMD->getZExtValue());
   }
+
+  // For all HLSL Shader functions
+  for (auto &F : M.functions()) {
+    if (!F.hasFnAttribute("hlsl.shader"))
+      continue;
+
+    EntryProperties EFP{};
+    // Get "hlsl.shader" attribute
+    Attribute EntryAttr = F.getFnAttribute("hlsl.shader");
+    assert(EntryAttr.isValid() &&
+           "Invalid value specified for HLSL function attribute hlsl.shader");
+    StringRef EntryProfile = EntryAttr.getValueAsString();
+    Triple T("", "", "", EntryProfile);
+    EFP.ShaderStage = T.getEnvironment();
+    // Get numthreads attribute value, if one exists
+    StringRef NumThreadsStr =
+        F.getFnAttribute("hlsl.numthreads").getValueAsString();
+    if (!NumThreadsStr.empty()) {
+      SmallVector<StringRef> NumThreadsVec;
+      NumThreadsStr.split(NumThreadsVec, ',');
+      assert(NumThreadsVec.size() == 3 && "Invalid numthreads specified");
+      // Read in the three component values of numthreads
+      if (!llvm::to_integer(NumThreadsVec[0], EFP.NumThreadsX, 10))
+        assert(false && "Failed to parse X component of numthreads");
----------------
bogner wrote:

`if (x) assert(false)` is generally discouraged. It doesn't make much difference, but it's probably better 
```c++
    [[maybe_unused]] bool Success =
        llvm::to_integer(NumThreadsVec[0], EFP.NumThreadsX, 10);
    assert(Success&& "Failed to parse X component of numthreads");
```


https://github.com/llvm/llvm-project/pull/105728