Type::isSignedInteger() and isUnsignedInteger() did not properly account for

'char', which varies based on the target.

Instead of spreading target knowledge throughout the compiler, bifurcate char
into Char_S and Char_U, and have ASTContext create the right one based on the
target, when it starts up.

llvm-svn: 39577

clang/AST/ASTContext.cpp

@@ -110,7 +110,10 @@ void ASTContext::InitBuiltinTypes() {
   // C99 6.2.5p2.
   InitBuiltinType(BoolTy,              BuiltinType::Bool);
   // C99 6.2.5p3.
-  InitBuiltinType(CharTy,              BuiltinType::Char);
+  if (Target.isCharSigned(SourceLocation()))
+    InitBuiltinType(CharTy,            BuiltinType::Char_S);
+  else
+    InitBuiltinType(CharTy,            BuiltinType::Char_U);
   // C99 6.2.5p4.
   InitBuiltinType(SignedCharTy,        BuiltinType::SChar);
   InitBuiltinType(ShortTy,             BuiltinType::Short);
@@ -347,7 +350,8 @@ unsigned ASTContext::getIntegerBitwidth(QualType T, SourceLocation Loc) {
   switch (BT->getKind()) {
   default: assert(0 && "getIntegerBitwidth(): not a built-in integer");
   case BuiltinType::Bool:      return Target.getBoolWidth(Loc);
-  case BuiltinType::Char:
+  case BuiltinType::Char_S:
+  case BuiltinType::Char_U:
   case BuiltinType::SChar:
   case BuiltinType::UChar:     return Target.getCharWidth(Loc);
   case BuiltinType::Short:
@@ -375,7 +379,8 @@ static int getIntegerRank(QualType t) {
     assert(0 && "getIntegerRank(): not a built-in integer");
   case BuiltinType::Bool:
     return 1;
-  case BuiltinType::Char:
+  case BuiltinType::Char_S:
+  case BuiltinType::Char_U:
   case BuiltinType::SChar:
   case BuiltinType::UChar:
     return 2;
@@ -448,6 +453,8 @@ QualType ASTContext::maxFloatingType(QualType lt, QualType rt) {
 // maxIntegerType - Returns the highest ranked integer type. Handles 3 case:
 // unsigned/unsigned, signed/signed, signed/unsigned. C99 6.3.1.8p1.
 QualType ASTContext::maxIntegerType(QualType lhs, QualType rhs) {
+  if (lhs == rhs) return lhs;
+  
   bool t1Unsigned = lhs->isUnsignedIntegerType();
   bool t2Unsigned = rhs->isUnsignedIntegerType();
   

clang/AST/Type.cpp

@@ -15,6 +15,7 @@
 #include "clang/AST/Type.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/Expr.h"
+#include "clang/Basic/TargetInfo.h"
 #include "llvm/Support/Streams.h"
 
 using namespace llvm;
@@ -235,16 +236,18 @@ bool Type::isIntegerType() const {
 }
 
 bool Type::isSignedIntegerType() const {
-  if (const BuiltinType *BT = dyn_cast<BuiltinType>(CanonicalType))
-    return BT->getKind() >= BuiltinType::SChar &&
+  if (const BuiltinType *BT = dyn_cast<BuiltinType>(CanonicalType)) {
+    return BT->getKind() >= BuiltinType::Char_S &&
            BT->getKind() <= BuiltinType::LongLong;
+  }
   return false;
 }
 
 bool Type::isUnsignedIntegerType() const {
-  if (const BuiltinType *BT = dyn_cast<BuiltinType>(CanonicalType))
-    return BT->getKind() >= BuiltinType::UChar &&
+  if (const BuiltinType *BT = dyn_cast<BuiltinType>(CanonicalType)) {
+    return BT->getKind() >= BuiltinType::Bool &&
            BT->getKind() <= BuiltinType::ULongLong;
+  }
   return false;
 }
 
@@ -343,20 +346,20 @@ bool Type::isIncompleteType() const {
 }
 
 bool Type::isPromotableIntegerType() const {
-  if (const BuiltinType *BT = dyn_cast<BuiltinType>(CanonicalType)) {
-    switch (BT->getKind()) {
-      case BuiltinType::Bool:
-      case BuiltinType::Char:
-      case BuiltinType::SChar:
-      case BuiltinType::UChar:
-      case BuiltinType::Short:
-      case BuiltinType::UShort:
-        return true;
-      default: 
-        return false;
-    }
+  const BuiltinType *BT = dyn_cast<BuiltinType>(CanonicalType);
+  if (!BT) return false;
+  switch (BT->getKind()) {
+  case BuiltinType::Bool:
+  case BuiltinType::Char_S:
+  case BuiltinType::Char_U:
+  case BuiltinType::SChar:
+  case BuiltinType::UChar:
+  case BuiltinType::Short:
+  case BuiltinType::UShort:
+    return true;
+  default: 
+    return false;
   }
-  return false;
 }
 
 const char *BuiltinType::getName() const {
@@ -364,7 +367,8 @@ const char *BuiltinType::getName() const {
   default: assert(0 && "Unknown builtin type!");
   case Void:              return "void";
   case Bool:              return "_Bool";
-  case Char:              return "char";
+  case Char_S:            return "char";
+  case Char_U:            return "char";
   case SChar:             return "signed char";
   case Short:             return "short";
   case Int:               return "int";

clang/CodeGen/CGExpr.cpp

@@ -37,7 +37,8 @@ Value *CodeGenFunction::EvaluateScalarValueToBool(ExprResult Val, QualType Ty) {
       assert(Result->getType() == llvm::Type::Int1Ty &&
              "Unexpected bool value type!");
       return Result;
-    case BuiltinType::Char:
+    case BuiltinType::Char_S:
+    case BuiltinType::Char_U:
     case BuiltinType::SChar:
     case BuiltinType::UChar:
     case BuiltinType::Short:
@@ -190,8 +191,6 @@ ExprResult CodeGenFunction::EmitExprWithUsualUnaryConversions(const Expr *E,
     // FIXME: this probably isn't right, pending clarification from Steve.
     llvm::Value *Val = EmitExpr(E).getVal();
     
-    // FIXME: this doesn't handle 'char'!.
-    
     // If the input is a signed integer, sign extend to the destination.
     if (ResTy->isSignedIntegerType()) {
       Val = Builder.CreateSExt(Val, LLVMIntTy, "promote");

clang/CodeGen/CodeGenFunction.cpp

@@ -51,7 +51,8 @@ const llvm::Type *CodeGenFunction::ConvertType(QualType T, SourceLocation Loc) {
     case BuiltinType::Void:
       // LLVM void type can only be used as the result of a function call.  Just
       // map to the same as char.
-    case BuiltinType::Char:
+    case BuiltinType::Char_S:
+    case BuiltinType::Char_U:
     case BuiltinType::SChar:
     case BuiltinType::UChar:
       return IntegerType::get(Target.getCharWidth(Loc));

clang/include/clang/AST/Type.h

@@ -233,8 +233,14 @@ public:
   
   /// More type predicates useful for type checking/promotion
   bool isPromotableIntegerType() const; // C99 6.3.1.1p2
-  bool isSignedIntegerType() const;     // C99 6.2.5p4
-  bool isUnsignedIntegerType() const;   // C99 6.2.5p6
+
+  /// isSignedIntegerType - Return true if this is an integer type that is
+  /// signed, according to C99 6.2.5p4.
+  bool isSignedIntegerType() const;
+
+  /// isUnsignedIntegerType - Return true if this is an integer type that is
+  /// unsigned, according to C99 6.2.5p6. Note that this returns true for _Bool.
+  bool isUnsignedIntegerType() const;
   
   /// isConstantSizeType - Return true if this is not a variable sized type,
   /// according to the rules of C99 6.7.5p3.  If Loc is non-null, it is set to
@@ -262,9 +268,23 @@ public:
 class BuiltinType : public Type {
 public:
   enum Kind {
-    Void, Bool, Char,
-    SChar,  Short,  Int,  Long,  LongLong,
-    UChar, UShort, UInt, ULong, ULongLong,
+    Void,
+    
+    Bool,     // This is bool and/or _Bool.
+    Char_U,   // This is 'char' for targets where char is unsigned.
+    UChar,    // This is explicitly qualified unsigned char.
+    UShort,
+    UInt,
+    ULong,
+    ULongLong,
+    
+    Char_S,   // This is 'char' for targets where char is signed.
+    SChar,    // This is explicitly qualified signed char.
+    Short,
+    Int,
+    Long,
+    LongLong,
+    
     Float, Double, LongDouble,
     FloatComplex, DoubleComplex, LongDoubleComplex
   };