Revert r166223 and the subsequent commits that depend on it, r166230 & r166235.

This seems to have introduced assertion hit when building compiler-rt.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166245 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 70 insertions, 68 deletions

diff --git a/include/clang/Driver/Arg.h b/include/clang/Driver/Arg.h
index bd4fa872ea..70f0741520 100644
--- a/include/clang/Driver/Arg.h
+++ b/include/clang/Driver/Arg.h
@@ -15,8 +15,6 @@
 #ifndef CLANG_DRIVER_ARG_H_
 #define CLANG_DRIVER_ARG_H_
 
-#include "clang/Driver/Option.h"
-
 #include "Util.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
@@ -25,6 +23,7 @@
 namespace clang {
 namespace driver {
   class ArgList;
+  class Option;
 
   /// \brief A concrete instance of a particular driver option.
   ///
@@ -39,7 +38,7 @@ namespace driver {
 
   private:
     /// \brief The option this argument is an instance of.
-    const Option Opt;
+    const Option *Opt;
 
     /// \brief The argument this argument was derived from (during tool chain
     /// argument translation), if any.
@@ -61,14 +60,14 @@ namespace driver {
     SmallVector<const char *, 2> Values;
 
   public:
-    Arg(const Option Opt, unsigned Index, const Arg *BaseArg = 0);
-    Arg(const Option Opt, unsigned Index,
+    Arg(const Option *Opt, unsigned Index, const Arg *BaseArg = 0);
+    Arg(const Option *Opt, unsigned Index,
         const char *Value0, const Arg *BaseArg = 0);
-    Arg(const Option Opt, unsigned Index,
+    Arg(const Option *Opt, unsigned Index,
         const char *Value0, const char *Value1, const Arg *BaseArg = 0);
     ~Arg();
 
-    const Option getOption() const { return Opt; }
+    const Option &getOption() const { return *Opt; }
     unsigned getIndex() const { return Index; }
 
     /// \brief Return the base argument which generated this arg.
diff --git a/include/clang/Driver/ArgList.h b/include/clang/Driver/ArgList.h
index 72ed7bf586..b2570b01dd 100644
--- a/include/clang/Driver/ArgList.h
+++ b/include/clang/Driver/ArgList.h
@@ -11,7 +11,6 @@
 #define CLANG_DRIVER_ARGLIST_H_
 
 #include "clang/Basic/LLVM.h"
-#include "clang/Driver/Option.h"
 #include "clang/Driver/OptSpecifier.h"
 #include "clang/Driver/Util.h"
 #include "llvm/ADT/SmallVector.h"
@@ -375,14 +374,14 @@ namespace driver {
 
     /// AddFlagArg - Construct a new FlagArg for the given option \p Id and
     /// append it to the argument list.
-    void AddFlagArg(const Arg *BaseArg, const Option Opt) {
+    void AddFlagArg(const Arg *BaseArg, const Option *Opt) {
       append(MakeFlagArg(BaseArg, Opt));
     }
 
     /// AddPositionalArg - Construct a new Positional arg for the given option
     /// \p Id, with the provided \p Value and append it to the argument
     /// list.
-    void AddPositionalArg(const Arg *BaseArg, const Option Opt,
+    void AddPositionalArg(const Arg *BaseArg, const Option *Opt,
                           StringRef Value) {
       append(MakePositionalArg(BaseArg, Opt, Value));
     }
@@ -391,7 +390,7 @@ namespace driver {
     /// AddSeparateArg - Construct a new Positional arg for the given option
     /// \p Id, with the provided \p Value and append it to the argument
     /// list.
-    void AddSeparateArg(const Arg *BaseArg, const Option Opt,
+    void AddSeparateArg(const Arg *BaseArg, const Option *Opt,
                         StringRef Value) {
       append(MakeSeparateArg(BaseArg, Opt, Value));
     }
@@ -399,28 +398,28 @@ namespace driver {
 
     /// AddJoinedArg - Construct a new Positional arg for the given option
     /// \p Id, with the provided \p Value and append it to the argument list.
-    void AddJoinedArg(const Arg *BaseArg, const Option Opt,
+    void AddJoinedArg(const Arg *BaseArg, const Option *Opt,
                       StringRef Value) {
       append(MakeJoinedArg(BaseArg, Opt, Value));
     }
 
 
     /// MakeFlagArg - Construct a new FlagArg for the given option \p Id.
-    Arg *MakeFlagArg(const Arg *BaseArg, const Option Opt) const;
+    Arg *MakeFlagArg(const Arg *BaseArg, const Option *Opt) const;
 
     /// MakePositionalArg - Construct a new Positional arg for the
     /// given option \p Id, with the provided \p Value.
-    Arg *MakePositionalArg(const Arg *BaseArg, const Option Opt,
+    Arg *MakePositionalArg(const Arg *BaseArg, const Option *Opt,
                            StringRef Value) const;
 
     /// MakeSeparateArg - Construct a new Positional arg for the
     /// given option \p Id, with the provided \p Value.
-    Arg *MakeSeparateArg(const Arg *BaseArg, const Option Opt,
+    Arg *MakeSeparateArg(const Arg *BaseArg, const Option *Opt,
                          StringRef Value) const;
 
     /// MakeJoinedArg - Construct a new Positional arg for the
     /// given option \p Id, with the provided \p Value.
-    Arg *MakeJoinedArg(const Arg *BaseArg, const Option Opt,
+    Arg *MakeJoinedArg(const Arg *BaseArg, const Option *Opt,
                        StringRef Value) const;
 
     /// @}
diff --git a/include/clang/Driver/OptTable.h b/include/clang/Driver/OptTable.h
index 678d967659..ea7e57b12b 100644
--- a/include/clang/Driver/OptTable.h
+++ b/include/clang/Driver/OptTable.h
@@ -47,6 +47,15 @@ namespace driver {
     const Info *OptionInfos;
     unsigned NumOptionInfos;
 
+    /// \brief The lazily constructed options table, indexed by option::ID - 1.
+    mutable Option **Options;
+
+    /// \brief Prebound input option instance.
+    const Option *TheInputOption;
+
+    /// \brief Prebound unknown option instance.
+    const Option *TheUnknownOption;
+
     /// The index of the first option which can be parsed (i.e., is not a
     /// special option like 'input' or 'unknown', and is not an option group).
     unsigned FirstSearchableIndex;
@@ -58,6 +67,8 @@ namespace driver {
       return OptionInfos[id - 1];
     }
 
+    Option *CreateOption(unsigned id) const;
+
   protected:
     OptTable(const Info *_OptionInfos, unsigned _NumOptionInfos);
   public:
@@ -70,7 +81,17 @@ namespace driver {
     /// if necessary.
     ///
     /// \return The option, or null for the INVALID option id.
-    const Option getOption(OptSpecifier Opt) const;
+    const Option *getOption(OptSpecifier Opt) const {
+      unsigned id = Opt.getID();
+      if (id == 0)
+        return 0;
+
+      assert((unsigned) (id - 1) < getNumOptions() && "Invalid ID.");
+      Option *&Entry = Options[id - 1];
+      if (!Entry)
+        Entry = CreateOption(id);
+      return Entry;
+    }
 
     /// \brief Lookup the name of the given option.
     const char *getOptionName(OptSpecifier id) const {
diff --git a/include/clang/Driver/Option.h b/include/clang/Driver/Option.h
index 11e417149d..6fc8bef5da 100644
--- a/include/clang/Driver/Option.h
+++ b/include/clang/Driver/Option.h
@@ -21,20 +21,15 @@ namespace driver {
   class ArgList;
 
 namespace options {
-  /// Base flags for all options. Custom flags may be added after.
   enum DriverFlag {
-    HelpHidden       = (1 << 0),
-    RenderAsInput    = (1 << 1),
-    RenderJoined     = (1 << 2),
-    RenderSeparate   = (1 << 3)
-  };
-
-  /// Flags specifically for clang options.
-  enum ClangFlags {
-    DriverOption     = (1 << 4),
-    LinkerInput      = (1 << 5),
-    NoArgumentUnused = (1 << 6),
-    NoForward        = (1 << 7),
+    DriverOption     = (1 << 0),
+    HelpHidden       = (1 << 1),
+    LinkerInput      = (1 << 2),
+    NoArgumentUnused = (1 << 3),
+    NoForward        = (1 << 4),
+    RenderAsInput    = (1 << 5),
+    RenderJoined     = (1 << 6),
+    RenderSeparate   = (1 << 7),
     Unsupported      = (1 << 8),
     CC1Option        = (1 << 9)
   };
@@ -73,7 +68,7 @@ namespace options {
       RenderValuesStyle
     };
 
-  protected:
+  private:
     const OptTable::Info *Info;
     const OptTable *Owner;
 
@@ -81,38 +76,17 @@ namespace options {
     Option(const OptTable::Info *Info, const OptTable *Owner);
     ~Option();
 
-    bool isValid() const {
-      return Info != 0;
-    }
-
-    unsigned getID() const {
-      assert(Info && "Must have a valid info!");
-      return Info->ID;
-    }
-
-    OptionClass getKind() const {
-      assert(Info && "Must have a valid info!");
-      return OptionClass(Info->Kind);
-    }
-
-    StringRef getName() const {
-      assert(Info && "Must have a valid info!");
-      return Info->Name;
-    }
+    unsigned getID() const { return Info->ID; }
+    OptionClass getKind() const { return OptionClass(Info->Kind); }
+    StringRef getName() const { return Info->Name; }
+    const Option *getGroup() const { return Owner->getOption(Info->GroupID); }
+    const Option *getAlias() const { return Owner->getOption(Info->AliasID); }
 
-    const Option getGroup() const {
-      assert(Info && "Must have a valid info!");
-      assert(Owner && "Must have a valid owner!");
-      return Owner->getOption(Info->GroupID);
-    }
+    unsigned getNumArgs() const { return Info->Param; }
 
-    const Option getAlias() const {
-      assert(Info && "Must have a valid info!");
-      assert(Owner && "Must have a valid owner!");
-      return Owner->getOption(Info->AliasID);
-    }
+    bool isUnsupported() const { return Info->Flags & options::Unsupported; }
 
-    unsigned getNumArgs() const { return Info->Param; }
+    bool isLinkerInput() const { return Info->Flags & options::LinkerInput; }
 
     bool hasNoOptAsInput() const { return Info->Flags & options::RenderAsInput;}
 
@@ -140,23 +114,32 @@ namespace options {
       llvm_unreachable("Unexpected kind!");
     }
 
-    /// Test if this option has the flag \a Val.
-    bool hasFlag(unsigned Val) const {
-      return Info->Flags & Val;
+    bool isDriverOption() const { return Info->Flags & options::DriverOption; }
+
+    bool hasNoArgumentUnused() const {
+      return Info->Flags & options::NoArgumentUnused;
+    }
+
+    bool hasNoForward() const { return Info->Flags & options::NoForward; }
+
+    bool isCC1Option() const { return Info->Flags & options::CC1Option; }
+
+    bool hasForwardToGCC() const {
+      return !hasNoForward() && !isDriverOption() && !isLinkerInput();
     }
 
     /// getUnaliasedOption - Return the final option this option
     /// aliases (itself, if the option has no alias).
-    const Option getUnaliasedOption() const {
-      const Option Alias = getAlias();
-      if (Alias.isValid()) return Alias.getUnaliasedOption();
-      return *this;
+    const Option *getUnaliasedOption() const {
+      const Option *Alias = getAlias();
+      if (Alias) return Alias->getUnaliasedOption();
+      return this;
     }
 
     /// getRenderName - Return the name to use when rendering this
     /// option.
     StringRef getRenderName() const {
-      return getUnaliasedOption().getName();
+      return getUnaliasedOption()->getName();
     }
 
     /// matches - Predicate for whether this option is part of the