Compute feature bits at time of MCSubtargetInfo initialization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134606 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 29 insertions, 19 deletions

diff --git a/include/llvm/MC/MCSubtargetInfo.h b/include/llvm/MC/MCSubtargetInfo.h
index d855271227..610a4da9d2 100644
--- a/include/llvm/MC/MCSubtargetInfo.h
+++ b/include/llvm/MC/MCSubtargetInfo.h
@@ -34,30 +34,29 @@ class MCSubtargetInfo {
   const unsigned *ForwardingPathes;    // Forwarding pathes
   unsigned NumFeatures;                // Number of processor features
   unsigned NumProcs;                   // Number of processors
-    
+  unsigned FeatureBits;                // Feature bits for current CPU
+
 public:
-  void InitMCSubtargetInfo(const SubtargetFeatureKV *PF,
+  void InitMCSubtargetInfo(StringRef CPU, StringRef FS,
+                           const SubtargetFeatureKV *PF,
                            const SubtargetFeatureKV *PD,
                            const SubtargetInfoKV *PI, const InstrStage *IS,
                            const unsigned *OC, const unsigned *FP,
-                           unsigned NF, unsigned NP) {
-    ProcFeatures = PF;
-    ProcDesc = PD;
-    ProcItins = PI;
-    Stages = IS;
-    OperandCycles = OC;
-    ForwardingPathes = FP;
-    NumFeatures = NF;
-    NumProcs = NP;
+                           unsigned NF, unsigned NP);
+
+  /// getFeatureBits - Get the feature bits.
+  ///
+  uint64_t getFeatureBits() const {
+    return FeatureBits;
   }
 
+  /// ReInitMCSubtargetInfo - Change CPU (and optionally supplemented with
+  /// feature string), recompute and return feature bits.
+  uint64_t ReInitMCSubtargetInfo(StringRef CPU, StringRef FS);
+
   /// getInstrItineraryForCPU - Get scheduling itinerary of a CPU.
   ///
   InstrItineraryData getInstrItineraryForCPU(StringRef CPU) const;
-
-  /// getFeatureBits - Get the feature bits for a CPU (optionally supplemented
-  /// with feature string).
-  uint64_t getFeatureBits(StringRef CPU, StringRef FS) const;
 };
 
 } // End llvm namespace
diff --git a/include/llvm/Target/TargetRegistry.h b/include/llvm/Target/TargetRegistry.h
index 4c7783559a..efc4438014 100644
--- a/include/llvm/Target/TargetRegistry.h
+++ b/include/llvm/Target/TargetRegistry.h
@@ -70,7 +70,9 @@ namespace llvm {
                                           StringRef TT);
     typedef MCInstrInfo *(*MCInstrInfoCtorFnTy)(void);
     typedef MCRegisterInfo *(*MCRegInfoCtorFnTy)(void);
-    typedef MCSubtargetInfo *(*MCSubtargetInfoCtorFnTy)(void);
+    typedef MCSubtargetInfo *(*MCSubtargetInfoCtorFnTy)(StringRef TT,
+                                                        StringRef CPU,
+                                                        StringRef Features);
     typedef TargetMachine *(*TargetMachineCtorTy)(const Target &T,
                                                   const std::string &TT,
                                                   const std::string &CPU,
@@ -269,10 +271,18 @@ namespace llvm {
 
     /// createMCSubtargetInfo - Create a MCSubtargetInfo implementation.
     ///
-    MCSubtargetInfo *createMCSubtargetInfo() const {
+    /// \arg Triple - This argument is used to determine the target machine
+    /// feature set; it should always be provided. Generally this should be
+    /// either the target triple from the module, or the target triple of the
+    /// host if that does not exist.
+    /// \arg CPU - This specifies the name of the target CPU.
+    /// \arg Features - This specifies the string representation of the
+    /// additional target features.
+    MCSubtargetInfo *createMCSubtargetInfo(StringRef Triple, StringRef CPU,
+                                           StringRef Features) const {
       if (!MCSubtargetInfoCtorFn)
         return 0;
-      return MCSubtargetInfoCtorFn();
+      return MCSubtargetInfoCtorFn(Triple, CPU, Features);
     }
 
     /// createTargetMachine - Create a target specific machine implementation
@@ -824,7 +834,8 @@ namespace llvm {
       TargetRegistry::RegisterMCSubtargetInfo(T, &Allocator);
     }
   private:
-    static MCSubtargetInfo *Allocator() {
+    static MCSubtargetInfo *Allocator(StringRef TT, StringRef CPU,
+                                      StringRef FS) {
       return new MCSubtargetInfoImpl();
     }
   };