[clang] [CIR] cir.call with scalar return type (PR #135552)

[Erich Keane via cfe-commits]

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@@ -18,9 +18,12 @@
 using namespace clang;
 using namespace clang::CIRGen;
 
-CIRGenFunctionInfo *CIRGenFunctionInfo::create() {
-  // For now we just create an empty CIRGenFunctionInfo.
-  CIRGenFunctionInfo *fi = new CIRGenFunctionInfo();
+CIRGenFunctionInfo *CIRGenFunctionInfo::create(CanQualType resultType) {
+  void *buffer = operator new(totalSizeToAlloc<ArgInfo>(1));
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erichkeane wrote:

This is REALLY strange to be calling global-operator-new directly, and we probably don't want to.

Additionally, we use allocators in the 'context' somewhere, so I suspect that MLIRContext has an allocator?  

THOUGH It looks from `https://mlir.llvm.org/doxygen/IR_2Operation_8cpp_source.html#l00082` that mlir might be calling `malloc`, which is curious.

What is our allocation story for MLIR/CIR?

https://github.com/llvm/llvm-project/pull/135552