[clang] [CIR] Upstream cir.call with scalar arguments (PR #136810)

[Sirui Mu via cfe-commits]

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@@ -18,22 +18,118 @@
 using namespace clang;
 using namespace clang::CIRGen;
 
-CIRGenFunctionInfo *CIRGenFunctionInfo::create(CanQualType resultType) {
-  void *buffer = operator new(totalSizeToAlloc<ArgInfo>(1));
+CIRGenFunctionInfo *
+CIRGenFunctionInfo::create(CanQualType resultType,
+                           llvm::ArrayRef<CanQualType> argTypes) {
+  void *buffer = operator new(totalSizeToAlloc<ArgInfo>(argTypes.size() + 1));
 
   CIRGenFunctionInfo *fi = new (buffer) CIRGenFunctionInfo();
+  fi->numArgs = argTypes.size();
   fi->getArgsBuffer()[0].type = resultType;
+  for (unsigned i = 0; i < argTypes.size(); ++i)
+    fi->getArgsBuffer()[i + 1].type = argTypes[i];
 
   return fi;
 }
 
+namespace {
+
+/// Encapsulates information about the way function arguments from
+/// CIRGenFunctionInfo should be passed to actual CIR function.
+class ClangToCIRArgMapping {
+  static constexpr unsigned invalidIndex = ~0U;
+  unsigned totalNumCIRArgs;
+
+  /// Arguments of CIR function corresponding to single Clang argument.
+  struct CIRArgs {
+    // Argument is expanded to CIR arguments at positions
+    // [FirstArgIndex, FirstArgIndex + NumberOfArgs).
+    unsigned firstArgIndex = 0;
+    unsigned numberOfArgs = 0;
+
+    CIRArgs() : firstArgIndex(invalidIndex), numberOfArgs(0) {}
+  };
+
+  SmallVector<CIRArgs, 8> argInfo;
+
+public:
+  ClangToCIRArgMapping(const ASTContext &astContext,
+                       const CIRGenFunctionInfo &funcInfo)
+      : totalNumCIRArgs(0), argInfo(funcInfo.arg_size()) {
+    construct(astContext, funcInfo);
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Lancern wrote:

I'm not sure the exact reason, the incubator has it and I'm following the incubator. The `construct` function only has a single caller. I updated the code and inlined the `construct` function.

https://github.com/llvm/llvm-project/pull/136810