AST representation for user-defined literals, plus just enough of semantic

analysis to make the AST representation testable. They are represented by a
new UserDefinedLiteral AST node, which is a sugared CallExpr. All semantic
properties, including full CodeGen support, are achieved for free by this
representation.

UserDefinedLiterals can never be dependent, so no custom instantiation
behavior is required. They are mangled as if they were direct calls to the
underlying literal operator. This matches g++'s apparent behavior (but not its
actual mangling, which is broken for literal-operator-ids).

User-defined *string* literals are now fully-operational, but the semantic
analysis is quite hacky and needs more work. No other forms of user-defined
literal are created yet, but the AST support for them is present.

This patch committed after midnight because we had already hit the quota for
new kinds of literal yesterday.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@152211 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 33 insertions, 0 deletions

diff --git a/lib/AST/ExprCXX.cpp b/lib/AST/ExprCXX.cpp
index dc559f0940..039d70cfc5 100644
--- a/lib/AST/ExprCXX.cpp
+++ b/lib/AST/ExprCXX.cpp
@@ -624,6 +624,39 @@ CXXFunctionalCastExpr::CreateEmpty(ASTContext &C, unsigned PathSize) {
   return new (Buffer) CXXFunctionalCastExpr(EmptyShell(), PathSize);
 }
 
+UserDefinedLiteral::LiteralOperatorKind
+UserDefinedLiteral::getLiteralOperatorKind() const {
+  if (getNumArgs() == 0)
+    return LOK_Template;
+  if (getNumArgs() == 2)
+    return LOK_String;
+
+  assert(getNumArgs() == 1 && "unexpected #args in literal operator call");
+  QualType ParamTy =
+    cast<FunctionDecl>(getCalleeDecl())->getParamDecl(0)->getType();
+  if (ParamTy->isPointerType())
+    return LOK_Raw;
+  if (ParamTy->isAnyCharacterType())
+    return LOK_Character;
+  if (ParamTy->isIntegerType())
+    return LOK_Integer;
+  if (ParamTy->isFloatingType())
+    return LOK_Floating;
+
+  llvm_unreachable("unknown kind of literal operator");
+}
+
+Expr *UserDefinedLiteral::getCookedLiteral() {
+#ifndef NDEBUG
+  LiteralOperatorKind LOK = getLiteralOperatorKind();
+  assert(LOK != LOK_Template && LOK != LOK_Raw && "not a cooked literal");
+#endif
+  return getArg(0);
+}
+
+const IdentifierInfo *UserDefinedLiteral::getUDSuffix() const {
+  return cast<FunctionDecl>(getCalleeDecl())->getLiteralIdentifier();
+}
 
 CXXDefaultArgExpr *
 CXXDefaultArgExpr::Create(ASTContext &C, SourceLocation Loc,