[CIR] Follow-up to floating-point upstream change

Fix the opening comment on some newly added files.

Add asserts that the Clang types `float` and `double` are IEEE 32-bit
and 64-bit.

Author: dkolsen-pgi

clang/include/clang/CIR/Interfaces/CIRFPTypeInterface.td

@@ -1,10 +1,14 @@
-//===- CIRFPTypeInterface.td - CIR FP Interface Definitions -----*- C++ -*-===//
+//===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
+//
+// Defines the interface to generically handle CIR floating-point types.
+//
+//===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_INCLUDE_CLANG_CIR_INTERFACES_CIRFPTYPEINTERFACE_TD
 #define LLVM_CLANG_INCLUDE_CLANG_CIR_INTERFACES_CIRFPTYPEINTERFACE_TD

clang/lib/CIR/CodeGen/CIRGenTypes.cpp

@@ -30,7 +30,7 @@ bool CIRGenTypes::isFuncParamTypeConvertible(clang::QualType type) {
   // certain circumstances have been reached.
   assert(!type->getAs<MemberPointerType>() && "NYI");
 
-  // If this isn't a tagged type, we can convert it!
+  // If this isn't a tag type, we can convert it.
   const TagType *tagType = type->getAs<TagType>();
   if (!tagType)
     return true;
@@ -171,9 +171,15 @@ mlir::Type CIRGenTypes::convertType(QualType type) {
       resultType = cgm.BFloat16Ty;
       break;
     case BuiltinType::Float:
+      assert(&astContext.getFloatTypeSemantics(type) ==
+                 &llvm::APFloat::IEEEsingle() &&
+             "ClangIR only supports float as IEEE 32-bit");
       resultType = cgm.FloatTy;
       break;
     case BuiltinType::Double:
+      assert(&astContext.getFloatTypeSemantics(type) ==
+                 &llvm::APFloat::IEEEdouble() &&
+             "ClangIR only supports double as IEEE 64-bit");
       resultType = cgm.DoubleTy;
       break;
     case BuiltinType::LongDouble:

clang/lib/CIR/Interfaces/CIRFPTypeInterface.cpp

@@ -1,10 +1,14 @@
-//====- CIRFPTypeInterface.cpp - Interface for floating-point types -------===//
+//===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
+//
+// Defines the interface to generically handle CIR floating-point types.
+//
+//===----------------------------------------------------------------------===//
 
 #include "clang/CIR/Interfaces/CIRFPTypeInterface.h"