DataLayout::getTypeSizeInBits may get error result when input type is !cir.long_double<!cir.f80>

[PikachuHyA]

I am refactoring the code in #1033 by replacing the manually implemented switch-case statements with DataLayout::getTypeSizeInBits.

During this process, I noticed that DataLayout::getTypeSizeInBits(!cir.long_double<!cir.f80>) returns 16 bits when I expected it to return 80 bits. This discrepancy is causing the test cases to fail.

For reference, you can find the relevant code in ClangIR

clangir/clang/lib/CIR/Dialect/IR/CIRTypes.cpp

Lines 749 to 754 in fca6e2c

	llvm::TypeSize
	FP80Type::getTypeSizeInBits(const mlir::DataLayout &dataLayout,
	mlir::DataLayoutEntryListRef params) const {
	return llvm::TypeSize::getFixed(16);
	}

and the LLVM IR code

clangir/llvm/include/llvm/IR/DataLayout.h

Lines 622 to 674 in fca6e2c

	// The implementation of this method is provided inline as it is particularly
	// well suited to constant folding when called on a specific Type subclass.
	inline TypeSize DataLayout::getTypeSizeInBits(Type *Ty) const {
	assert(Ty->isSized() && "Cannot getTypeInfo() on a type that is unsized!");
	switch (Ty->getTypeID()) {
	case Type::LabelTyID:
	return TypeSize::getFixed(getPointerSizeInBits(0));
	case Type::PointerTyID:
	return TypeSize::getFixed(
	getPointerSizeInBits(Ty->getPointerAddressSpace()));
	case Type::ArrayTyID: {
	ArrayType *ATy = cast<ArrayType>(Ty);
	return ATy->getNumElements() *
	getTypeAllocSizeInBits(ATy->getElementType());
	}
	case Type::StructTyID:
	// Get the layout annotation... which is lazily created on demand.
	return getStructLayout(cast<StructType>(Ty))->getSizeInBits();
	case Type::IntegerTyID:
	return TypeSize::getFixed(Ty->getIntegerBitWidth());
	case Type::HalfTyID:
	case Type::BFloatTyID:
	return TypeSize::getFixed(16);
	case Type::FloatTyID:
	return TypeSize::getFixed(32);
	case Type::DoubleTyID:
	return TypeSize::getFixed(64);
	case Type::PPC_FP128TyID:
	case Type::FP128TyID:
	return TypeSize::getFixed(128);
	case Type::X86_AMXTyID:
	return TypeSize::getFixed(8192);
	// In memory objects this is always aligned to a higher boundary, but
	// only 80 bits contain information.
	case Type::X86_FP80TyID:
	return TypeSize::getFixed(80);
	case Type::FixedVectorTyID:
	case Type::ScalableVectorTyID: {
	VectorType *VTy = cast<VectorType>(Ty);
	auto EltCnt = VTy->getElementCount();
	uint64_t MinBits = EltCnt.getKnownMinValue() *
	getTypeSizeInBits(VTy->getElementType()).getFixedValue();
	return TypeSize(MinBits, EltCnt.isScalable());
	}
	case Type::TargetExtTyID: {
	Type *LayoutTy = cast<TargetExtType>(Ty)->getLayoutType();
	return getTypeSizeInBits(LayoutTy);
	}
	default:
	llvm_unreachable("DataLayout::getTypeSizeInBits(): Unsupported type");
	}
	}

For additional context, please see #536 .

[PikachuHyA]

cc @Lancern

[PikachuHyA]

FP128

clangir/clang/lib/CIR/Dialect/IR/CIRTypes.cpp

Lines 770 to 774 in fca6e2c

	llvm::TypeSize
	FP128Type::getTypeSizeInBits(const mlir::DataLayout &dataLayout,
	mlir::DataLayoutEntryListRef params) const {
	return llvm::TypeSize::getFixed(16);
	}

see #966