[Fixed Point Arithmetic] Addition of the remaining fixed point types and their saturated equivalents

This diff includes changes for the remaining _Fract and _Sat fixed point types.

```
signed short _Fract s_short_fract;
signed _Fract s_fract;
signed long _Fract s_long_fract;
unsigned short _Fract u_short_fract;
unsigned _Fract u_fract;
unsigned long _Fract u_long_fract;

// Aliased fixed point types
short _Accum short_accum;
_Accum accum;
long _Accum long_accum;
short _Fract short_fract;
_Fract fract;
long _Fract long_fract;

// Saturated fixed point types
_Sat signed short _Accum sat_s_short_accum;
_Sat signed _Accum sat_s_accum;
_Sat signed long _Accum sat_s_long_accum;
_Sat unsigned short _Accum sat_u_short_accum;
_Sat unsigned _Accum sat_u_accum;
_Sat unsigned long _Accum sat_u_long_accum;
_Sat signed short _Fract sat_s_short_fract;
_Sat signed _Fract sat_s_fract;
_Sat signed long _Fract sat_s_long_fract;
_Sat unsigned short _Fract sat_u_short_fract;
_Sat unsigned _Fract sat_u_fract;
_Sat unsigned long _Fract sat_u_long_fract;

// Aliased saturated fixed point types
_Sat short _Accum sat_short_accum;
_Sat _Accum sat_accum;
_Sat long _Accum sat_long_accum;
_Sat short _Fract sat_short_fract;
_Sat _Fract sat_fract;
_Sat long _Fract sat_long_fract;
```

This diff only allows for declaration of these fixed point types. Assignment and other operations done on fixed point types according to http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1169.pdf will be added in future patches.

Differential Revision: https://reviews.llvm.org/D46911

llvm-svn: 334718

1 files changed, 32 insertions, 3 deletions

diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 2b9c4afaaf1..9e4669a8720 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -2876,6 +2876,17 @@ Parser::DiagnoseMissingSemiAfterTagDefinition(DeclSpec &DS, AccessSpecifier AS,
   return false;
 }
 
+// Choose the apprpriate diagnostic error for why fixed point types are
+// disabled, set the previous specifier, and mark as invalid.
+static void SetupFixedPointError(const LangOptions &LangOpts,
+                                 const char *&PrevSpec, unsigned &DiagID,
+                                 bool &isInvalid) {
+  assert(!LangOpts.FixedPoint);
+  DiagID = diag::err_fixed_point_not_enabled;
+  PrevSpec = "";  // Not used by diagnostic
+  isInvalid = true;
+}
+
 /// ParseDeclarationSpecifiers
 ///       declaration-specifiers: [C99 6.7]
 ///         storage-class-specifier declaration-specifiers[opt]
@@ -3582,14 +3593,27 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       break;
     case tok::kw__Accum:
       if (!getLangOpts().FixedPoint) {
-        DiagID = diag::err_fixed_point_not_enabled;
-        PrevSpec = "";  // Not used by diagnostic
-        isInvalid = true;
+        SetupFixedPointError(getLangOpts(), PrevSpec, DiagID, isInvalid);
       } else {
         isInvalid = DS.SetTypeSpecType(DeclSpec::TST_accum, Loc, PrevSpec,
                                        DiagID, Policy);
       }
       break;
+    case tok::kw__Fract:
+      if (!getLangOpts().FixedPoint) {
+        SetupFixedPointError(getLangOpts(), PrevSpec, DiagID, isInvalid);
+      } else {
+        isInvalid = DS.SetTypeSpecType(DeclSpec::TST_fract, Loc, PrevSpec,
+                                       DiagID, Policy);
+      }
+      break;
+    case tok::kw__Sat:
+      if (!getLangOpts().FixedPoint) {
+        SetupFixedPointError(getLangOpts(), PrevSpec, DiagID, isInvalid);
+      } else {
+        isInvalid = DS.SetTypeSpecSat(Loc, PrevSpec, DiagID);
+      }
+      break;
     case tok::kw___float128:
       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_float128, Loc, PrevSpec,
                                      DiagID, Policy);
@@ -4617,6 +4641,7 @@ bool Parser::isKnownToBeTypeSpecifier(const Token &Tok) const {
   case tok::kw_float:
   case tok::kw_double:
   case tok::kw__Accum:
+  case tok::kw__Fract:
   case tok::kw__Float16:
   case tok::kw___float128:
   case tok::kw_bool:
@@ -4695,6 +4720,7 @@ bool Parser::isTypeSpecifierQualifier() {
   case tok::kw_float:
   case tok::kw_double:
   case tok::kw__Accum:
+  case tok::kw__Fract:
   case tok::kw__Float16:
   case tok::kw___float128:
   case tok::kw_bool:
@@ -4718,6 +4744,7 @@ bool Parser::isTypeSpecifierQualifier() {
   case tok::kw_const:
   case tok::kw_volatile:
   case tok::kw_restrict:
+  case tok::kw__Sat:
 
     // Debugger support.
   case tok::kw___unknown_anytype:
@@ -4854,6 +4881,7 @@ bool Parser::isDeclarationSpecifier(bool DisambiguatingWithExpression) {
   case tok::kw_float:
   case tok::kw_double:
   case tok::kw__Accum:
+  case tok::kw__Fract:
   case tok::kw__Float16:
   case tok::kw___float128:
   case tok::kw_bool:
@@ -4875,6 +4903,7 @@ bool Parser::isDeclarationSpecifier(bool DisambiguatingWithExpression) {
   case tok::kw_const:
   case tok::kw_volatile:
   case tok::kw_restrict:
+  case tok::kw__Sat:
 
     // function-specifier
   case tok::kw_inline: