[flang-commits] [flang] [flang] Add struct passing target rewrite hooks and partial X86-64 impl (PR #74829)

[Tom Eccles via flang-commits]

================
@@ -58,6 +59,62 @@ static void typeTodo(const llvm::fltSemantics *sem, mlir::Location loc,
   }
 }
 
+/// Return the size of alignment of FIR types.
+/// TODO: consider moving this to a DataLayoutTypeInterface implementation
+/// for FIR types. It should first be ensured that it is OK to open the gate of
+/// target dependent type size inquiries in lowering. It would also not be
+/// straightforward given the need for a kind map that would need to be
+/// converted in terms of mlir::DataLayoutEntryKey.
+static std::pair<std::uint64_t, unsigned short>
+getSizeAndAlignment(mlir::Location loc, mlir::Type ty,
+                    const mlir::DataLayout &dl,
+                    const fir::KindMapping &kindMap) {
+  if (mlir::isa<mlir::IntegerType, mlir::FloatType, mlir::ComplexType>(ty)) {
+    llvm::TypeSize size = dl.getTypeSize(ty);
+    unsigned short alignment = dl.getTypeABIAlignment(ty);
+    return {size, alignment};
+  }
+  if (auto firCmplx = mlir::dyn_cast<fir::ComplexType>(ty)) {
+    auto [floatSize, floatAlign] =
+        getSizeAndAlignment(loc, firCmplx.getEleType(kindMap), dl, kindMap);
+    return {llvm::alignTo(floatSize, floatAlign) + floatSize, floatAlign};
+  }
+  if (auto real = mlir::dyn_cast<fir::RealType>(ty))
+    return getSizeAndAlignment(loc, real.getFloatType(kindMap), dl, kindMap);
+
+  if (auto seqTy = mlir::dyn_cast<fir::SequenceType>(ty)) {
+    auto [eleSize, eleAlign] =
+        getSizeAndAlignment(loc, seqTy.getEleTy(), dl, kindMap);
+
+    std::uint64_t size =
+        llvm::alignTo(eleSize, eleAlign) * seqTy.getConstantArraySize();
+    return {size, eleAlign};
+  }
+  if (auto recTy = mlir::dyn_cast<fir::RecordType>(ty)) {
+    std::uint64_t size = 0;
+    unsigned short align = 8;
+    for (auto component : recTy.getTypeList()) {
+      auto [compSize, compAlign] =
+          getSizeAndAlignment(loc, component.second, dl, kindMap);
+      size =
+          llvm::alignTo(size, compAlign) + llvm::alignTo(compSize, compAlign);
+      align = std::max(align, compAlign);
+    }
+    return {size, align};
+  }
+  if (auto logical = mlir::dyn_cast<fir::LogicalType>(ty)) {
+    mlir::Type intTy = mlir::IntegerType::get(
+        logical.getContext(), kindMap.getLogicalBitsize(logical.getFKind()));
+    return getSizeAndAlignment(loc, intTy, dl, kindMap);
+  }
+  if (auto logical = mlir::dyn_cast<fir::CharacterType>(ty)) {
+    mlir::Type intTy = mlir::IntegerType::get(
+        logical.getContext(), kindMap.getLogicalBitsize(logical.getFKind()));
----------------
tblah wrote:

```suggestion
  if (auto character = mlir::dyn_cast<fir::CharacterType>(ty)) {
    mlir::Type intTy = mlir::IntegerType::get(
        character.getContext(), kindMap.getLogicalBitsize(character.getFKind()));
```

https://github.com/llvm/llvm-project/pull/74829