Add a enum to specify target scheduling preference: SchedulingForLatency or

SchedulingForRegPressure. Added corresponding methods to set / get the value.

llvm-svn: 25598

include/llvm/Target/TargetLowering.h

@@ -70,6 +70,11 @@ public:
     ZeroOrNegativeOneSetCCResult,  // SetCC returns a sign extended result.
   };
 
+  enum SchedPreference {
+    SchedulingForLatency,          // Scheduling for shortest total latency.
+    SchedulingForRegPressure,      // Scheduling for lowest register pressure.
+  };
+
   TargetLowering(TargetMachine &TM);
   virtual ~TargetLowering();
 
@@ -102,6 +107,11 @@ public:
   /// result register.
   SetCCResultValue getSetCCResultContents() const { return SetCCResultContents;}
 
+  /// getSchedulingPreference - Return target scheduling preference.
+  SchedPreference getSchedulingPreference() const {
+    return SchedPreferenceInfo;
+  }
+
   /// getRegClassFor - Return the register class that should be used for the
   /// specified value type.  This may only be called on legal types.
   TargetRegisterClass *getRegClassFor(MVT::ValueType VT) const {
@@ -261,6 +271,11 @@ protected:
   /// setcc operation in a register.
   void setSetCCResultContents(SetCCResultValue Ty) { SetCCResultContents = Ty; }
 
+  /// setSchedulingPreference - Specify the target scheduling preference.
+  void setSchedulingPreference(SchedPreference Pref) {
+    SchedPreferenceInfo = Pref;
+  }
+
   /// setShiftAmountFlavor - Describe how the target handles out of range shift
   /// amounts.
   void setShiftAmountFlavor(OutOfRangeShiftAmount OORSA) {
@@ -453,6 +468,10 @@ private:
   /// SetCCResultContents - Information about the contents of the high-bits in
   /// the result of a setcc comparison operation.
   SetCCResultValue SetCCResultContents;
+
+  /// SchedPreferenceInfo - The target scheduling preference: shortest possible
+  /// total cycles or lowest register usage.
+  SchedPreference SchedPreferenceInfo;
   
   /// UseUnderscoreSetJmpLongJmp - This target prefers to use _setjmp and
   /// _longjmp to implement llvm.setjmp/llvm.longjmp.  Defaults to false.