Stage two of getting CFE top correct.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@39734 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Parse/DeclSpec.cpp b/Parse/DeclSpec.cpp
new file mode 100644
index 0000000..117ff12
--- /dev/null
+++ b/Parse/DeclSpec.cpp
@@ -0,0 +1,285 @@
+//===--- SemaDeclSpec.cpp - Declaration Specifier Semantic Analysis -------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Chris Lattner and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file implements semantic analysis for declaration specifiers.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Parse/DeclSpec.h"
+#include "clang/Basic/LangOptions.h"
+#include "clang/Basic/SourceLocation.h"
+using namespace clang;
+
+/// getParsedSpecifiers - Return a bitmask of which flavors of specifiers this
+///
+unsigned DeclSpec::getParsedSpecifiers() const {
+  unsigned Res = 0;
+  if (StorageClassSpec != SCS_unspecified ||
+      SCS_thread_specified)
+    Res |= PQ_StorageClassSpecifier;
+  
+  if (TypeQualifiers != TQ_unspecified)
+    Res |= PQ_TypeQualifier;
+  
+  if (hasTypeSpecifier())
+    Res |= PQ_TypeSpecifier;
+  
+  if (FS_inline_specified)
+    Res |= PQ_FunctionSpecifier;
+  return Res;
+}
+
+const char *DeclSpec::getSpecifierName(DeclSpec::SCS S) {
+  switch (S) {
+  default: assert(0 && "Unknown typespec!");
+  case DeclSpec::SCS_unspecified: return "unspecified";
+  case DeclSpec::SCS_typedef:     return "typedef";
+  case DeclSpec::SCS_extern:      return "extern";
+  case DeclSpec::SCS_static:      return "static";
+  case DeclSpec::SCS_auto:        return "auto";
+  case DeclSpec::SCS_register:    return "register";
+  }
+}
+
+static bool BadSpecifier(DeclSpec::SCS S, const char *&PrevSpec) {
+  PrevSpec = DeclSpec::getSpecifierName(S);
+  return true;
+}
+
+static bool BadSpecifier(DeclSpec::TSW W, const char *&PrevSpec) {
+  switch (W) {
+  case DeclSpec::TSW_unspecified: PrevSpec = "unspecified"; break;
+  case DeclSpec::TSW_short:       PrevSpec = "short"; break;
+  case DeclSpec::TSW_long:        PrevSpec = "long"; break;
+  case DeclSpec::TSW_longlong:    PrevSpec = "long long"; break;
+  }
+  return true;
+}
+
+static bool BadSpecifier(DeclSpec::TSC C, const char *&PrevSpec) {
+  switch (C) {
+  case DeclSpec::TSC_unspecified: PrevSpec = "unspecified"; break;
+  case DeclSpec::TSC_imaginary:   PrevSpec = "imaginary"; break;
+  case DeclSpec::TSC_complex:     PrevSpec = "complex"; break;
+  }
+  return true;
+}
+
+
+static bool BadSpecifier(DeclSpec::TSS S, const char *&PrevSpec) {
+  switch (S) {
+  case DeclSpec::TSS_unspecified: PrevSpec = "unspecified"; break;
+  case DeclSpec::TSS_signed:      PrevSpec = "signed"; break;
+  case DeclSpec::TSS_unsigned:    PrevSpec = "unsigned"; break;
+  }
+  return true;
+}
+
+const char *DeclSpec::getSpecifierName(DeclSpec::TST T) {
+  switch (T) {
+  default: assert(0 && "Unknown typespec!");
+  case DeclSpec::TST_unspecified: return "unspecified";
+  case DeclSpec::TST_void:        return "void";
+  case DeclSpec::TST_char:        return "char";
+  case DeclSpec::TST_int:         return "int";
+  case DeclSpec::TST_float:       return "float";
+  case DeclSpec::TST_double:      return "double";
+  case DeclSpec::TST_bool:        return "_Bool";
+  case DeclSpec::TST_decimal32:   return "_Decimal32";
+  case DeclSpec::TST_decimal64:   return "_Decimal64";
+  case DeclSpec::TST_decimal128:  return "_Decimal128";
+  case DeclSpec::TST_enum:        return "enum";
+  case DeclSpec::TST_union:       return "union";
+  case DeclSpec::TST_struct:      return "struct";
+  case DeclSpec::TST_typedef:     return "typedef";
+  }
+}
+
+static bool BadSpecifier(DeclSpec::TST T, const char *&PrevSpec) {
+  PrevSpec = DeclSpec::getSpecifierName(T);
+  return true;
+}
+
+static bool BadSpecifier(DeclSpec::TQ T, const char *&PrevSpec) {
+  switch (T) {
+  case DeclSpec::TQ_unspecified: PrevSpec = "unspecified"; break;
+  case DeclSpec::TQ_const:       PrevSpec = "const"; break;
+  case DeclSpec::TQ_restrict:    PrevSpec = "restrict"; break;
+  case DeclSpec::TQ_volatile:    PrevSpec = "volatile"; break;
+  }
+  return true;
+}
+
+bool DeclSpec::SetStorageClassSpec(SCS S, SourceLocation Loc,
+                                   const char *&PrevSpec) {
+  if (StorageClassSpec != SCS_unspecified)
+    return BadSpecifier(StorageClassSpec, PrevSpec);
+  StorageClassSpec = S;
+  StorageClassSpecLoc = Loc;
+  return false;
+}
+
+bool DeclSpec::SetStorageClassSpecThread(SourceLocation Loc, 
+                                         const char *&PrevSpec) {
+  if (SCS_thread_specified) {
+    PrevSpec = "__thread";
+    return true;
+  }
+  SCS_thread_specified = true;
+  SCS_threadLoc = Loc;
+  return false;
+}
+
+
+/// These methods set the specified attribute of the DeclSpec, but return true
+/// and ignore the request if invalid (e.g. "extern" then "auto" is
+/// specified).
+bool DeclSpec::SetTypeSpecWidth(TSW W, SourceLocation Loc,
+                                const char *&PrevSpec) {
+  if (TypeSpecWidth != TSW_unspecified &&
+      // Allow turning long -> long long.
+      (W != TSW_longlong || TypeSpecWidth != TSW_long))
+    return BadSpecifier(TypeSpecWidth, PrevSpec);
+  TypeSpecWidth = W;
+  TSWLoc = Loc;
+  return false;
+}
+
+bool DeclSpec::SetTypeSpecComplex(TSC C, SourceLocation Loc, 
+                                  const char *&PrevSpec) {
+  if (TypeSpecComplex != TSC_unspecified)
+    return BadSpecifier(TypeSpecComplex, PrevSpec);
+  TypeSpecComplex = C;
+  TSCLoc = Loc;
+  return false;
+}
+
+bool DeclSpec::SetTypeSpecSign(TSS S, SourceLocation Loc, 
+                               const char *&PrevSpec) {
+  if (TypeSpecSign != TSS_unspecified)
+    return BadSpecifier(TypeSpecSign, PrevSpec);
+  TypeSpecSign = S;
+  TSSLoc = Loc;
+  return false;
+}
+
+bool DeclSpec::SetTypeSpecType(TST T, SourceLocation Loc,
+                               const char *&PrevSpec, void *Rep) {
+  if (TypeSpecType != TST_unspecified)
+    return BadSpecifier(TypeSpecType, PrevSpec);
+  TypeSpecType = T;
+  TypeRep = Rep;
+  TSTLoc = Loc;
+  return false;
+}
+
+bool DeclSpec::SetTypeQual(TQ T, SourceLocation Loc, const char *&PrevSpec,
+                           const LangOptions &Lang) {
+  // Duplicates turn into warnings pre-C99.
+  if ((TypeQualifiers & T) && !Lang.C99)
+    return BadSpecifier(T, PrevSpec);
+  TypeQualifiers |= T;
+  
+  switch (T) {
+  default: assert(0 && "Unknown type qualifier!");
+  case TQ_const:    TQ_constLoc = Loc; break;
+  case TQ_restrict: TQ_restrictLoc = Loc; break;
+  case TQ_volatile: TQ_volatileLoc = Loc; break;
+  }
+  return false;
+}
+
+bool DeclSpec::SetFunctionSpecInline(SourceLocation Loc, const char *&PrevSpec){
+  // 'inline inline' is ok.
+  FS_inline_specified = true;
+  FS_inlineLoc = Loc;
+  return false;
+}
+
+
+/// Finish - This does final analysis of the declspec, rejecting things like
+/// "_Imaginary" (lacking an FP type).  This returns a diagnostic to issue or
+/// diag::NUM_DIAGNOSTICS if there is no error.  After calling this method,
+/// DeclSpec is guaranteed self-consistent, even if an error occurred.
+void DeclSpec::Finish(Diagnostic &D, const LangOptions &Lang) {
+  // Check the type specifier components first.
+
+  // signed/unsigned are only valid with int/char.
+  if (TypeSpecSign != TSS_unspecified) {
+    if (TypeSpecType == TST_unspecified)
+      TypeSpecType = TST_int; // unsigned -> unsigned int, signed -> signed int.
+    else if (TypeSpecType != TST_int && TypeSpecType != TST_char) {
+      Diag(D, TSSLoc, diag::err_invalid_sign_spec,
+           getSpecifierName(TypeSpecType));
+      // signed double -> double.
+      TypeSpecSign = TSS_unspecified;
+    }
+  }
+
+  // Validate the width of the type.
+  switch (TypeSpecWidth) {
+  case TSW_unspecified: break;
+  case TSW_short:    // short int
+  case TSW_longlong: // long long int
+    if (TypeSpecType == TST_unspecified)
+      TypeSpecType = TST_int; // short -> short int, long long -> long long int.
+    else if (TypeSpecType != TST_int) {
+      Diag(D, TSWLoc,
+           TypeSpecWidth == TSW_short ? diag::err_invalid_short_spec
+                                      : diag::err_invalid_longlong_spec,
+           getSpecifierName(TypeSpecType));
+      TypeSpecType = TST_int;
+    }
+    break;
+  case TSW_long:  // long double, long int
+    if (TypeSpecType == TST_unspecified)
+      TypeSpecType = TST_int;  // long -> long int.
+    else if (TypeSpecType != TST_int && TypeSpecType != TST_double) {
+      Diag(D, TSWLoc, diag::err_invalid_long_spec,
+           getSpecifierName(TypeSpecType));
+      TypeSpecType = TST_int;
+    }
+    break;
+  }
+  
+  // TODO: if the implementation does not implement _Complex or _Imaginary,
+  // disallow their use.  Need information about the backend.
+  if (TypeSpecComplex != TSC_unspecified) {
+    if (TypeSpecType == TST_unspecified) {
+      Diag(D, TSCLoc, diag::ext_plain_complex);
+      TypeSpecType = TST_double;   // _Complex -> _Complex double.
+    } else if (TypeSpecType == TST_int || TypeSpecType == TST_char) {
+      // Note that this intentionally doesn't include _Complex _Bool.
+      Diag(D, TSTLoc, diag::ext_integer_complex);
+    } else if (TypeSpecType != TST_float && TypeSpecType != TST_double) {
+      Diag(D, TSCLoc, diag::err_invalid_complex_spec, 
+           getSpecifierName(TypeSpecType));
+      TypeSpecComplex = TSC_unspecified;
+    }
+  }
+  
+  // Verify __thread.
+  if (SCS_thread_specified) {
+    if (StorageClassSpec == SCS_unspecified) {
+      StorageClassSpec = SCS_extern; // '__thread int' -> 'extern __thread int'
+    } else if (StorageClassSpec != SCS_extern &&
+               StorageClassSpec != SCS_static) {
+      Diag(D, getStorageClassSpecLoc(), diag::err_invalid_thread_spec,
+           getSpecifierName(StorageClassSpec));
+      SCS_thread_specified = false;
+    }
+  }
+
+  // Okay, now we can infer the real type.
+  // TODO: infer real type.
+  
+  // TODO: return "auto function" and other bad things based on the real type.
+  
+  // 'data definition has no type or storage class'?
+}