rename SimplifyCompare -> SimplifyCmpInst and split it into

Simplify[IF]Cmp pieces.  Add some predicates to CmpInst to 
determine whether a predicate is fp or int.

llvm-svn: 86624

include/llvm/Analysis/InstructionSimplify.h

@@ -20,11 +20,24 @@ namespace llvm {
   class Value;
   class TargetData;
   
-  /// SimplifyCompare - Given operands for a CmpInst, see if we can
+  /// SimplifyICmpInst - Given operands for an ICmpInst, see if we can
   /// fold the result.  If not, this returns null.
-  Value *SimplifyCompare(unsigned Predicate, Value *LHS, Value *RHS,
+  Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
                          const TargetData *TD = 0);
   
+  /// SimplifyFCmpInst - Given operands for an FCmpInst, see if we can
+  /// fold the result.  If not, this returns null.
+  Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
+                         const TargetData *TD = 0);
+  
+
+  //=== Helper functions for higher up the class hierarchy.
+  
+  
+  /// SimplifyCmpInst - Given operands for a CmpInst, see if we can
+  /// fold the result.  If not, this returns null.
+  Value *SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
+                         const TargetData *TD = 0);
   
   /// SimplifyBinOp - Given operands for a BinaryOperator, see if we can
   /// fold the result.  If not, this returns null.

include/llvm/InstrTypes.h

@@ -658,7 +658,7 @@ public:
   /// @brief Create a CmpInst
   static CmpInst *Create(OtherOps Op, unsigned short predicate, Value *S1,
                          Value *S2, const Twine &Name, BasicBlock *InsertAtEnd);
-
+  
   /// @brief Get the opcode casted to the right type
   OtherOps getOpcode() const {
     return static_cast<OtherOps>(Instruction::getOpcode());
@@ -670,6 +670,18 @@ public:
   /// @brief Set the predicate for this instruction to the specified value.
   void setPredicate(Predicate P) { SubclassData = P; }
 
+  static bool isFPPredicate(Predicate P) {
+    return P >= FIRST_FCMP_PREDICATE && P <= LAST_FCMP_PREDICATE;
+  }
+  
+  static bool isIntPredicate(Predicate P) {
+    return P >= FIRST_ICMP_PREDICATE && P <= LAST_ICMP_PREDICATE;
+  }
+  
+  bool isFPPredicate() const { return isFPPredicate(getPredicate()); }
+  bool isIntPredicate() const { return isIntPredicate(getPredicate()); }
+  
+  
   /// For example, EQ -> NE, UGT -> ULE, SLT -> SGE,
   ///              OEQ -> UNE, UGT -> OLE, OLT -> UGE, etc.
   /// @returns the inverse predicate for the instruction's current predicate.

lib/Analysis/InstructionSimplify.cpp

@@ -32,11 +32,12 @@ Value *llvm::SimplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS,
 }
 
 
-/// SimplifyCompare - Given operands for a CmpInst, see if we can
-/// fold the result.
-Value *llvm::SimplifyCompare(unsigned Predicate, Value *LHS, Value *RHS,
-                             const TargetData *TD) {
+/// SimplifyICmpInst - Given operands for an ICmpInst, see if we can
+/// fold the result.  If not, this returns null.
+Value *llvm::SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
+                              const TargetData *TD) {
   CmpInst::Predicate Pred = (CmpInst::Predicate)Predicate;
+  assert(CmpInst::isIntPredicate(Pred) && "Not an integer compare!");
   
   if (Constant *CLHS = dyn_cast<Constant>(LHS))
     if (Constant *CRHS = dyn_cast<Constant>(RHS))
@@ -44,12 +45,36 @@ Value *llvm::SimplifyCompare(unsigned Predicate, Value *LHS, Value *RHS,
   
   // If this is an integer compare and the LHS and RHS are the same, fold it.
   if (LHS == RHS)
-    if (isa<IntegerType>(LHS->getType()) || isa<PointerType>(LHS->getType())) {
-      if (ICmpInst::isTrueWhenEqual(Pred))
-        return ConstantInt::getTrue(LHS->getContext());
-      else
-        return ConstantInt::getFalse(LHS->getContext());
-    }
+    if (ICmpInst::isTrueWhenEqual(Pred))
+      return ConstantInt::getTrue(LHS->getContext());
+    else
+      return ConstantInt::getFalse(LHS->getContext());
+
   return 0;
 }
 
+/// SimplifyFCmpInst - Given operands for an FCmpInst, see if we can
+/// fold the result.  If not, this returns null.
+Value *llvm::SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
+                              const TargetData *TD) {
+  CmpInst::Predicate Pred = (CmpInst::Predicate)Predicate;
+  assert(CmpInst::isFPPredicate(Pred) && "Not an FP compare!");
+
+  if (Constant *CLHS = dyn_cast<Constant>(LHS))
+    if (Constant *CRHS = dyn_cast<Constant>(RHS))
+      return ConstantFoldCompareInstOperands(Pred, CLHS, CRHS, TD);
+  
+  return 0;
+}
+
+
+
+/// SimplifyCmpInst - Given operands for a CmpInst, see if we can
+/// fold the result.
+Value *llvm::SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
+                             const TargetData *TD) {
+  if (CmpInst::isIntPredicate((CmpInst::Predicate)Predicate))
+    return SimplifyICmpInst(Predicate, LHS, RHS, TD);
+  return SimplifyFCmpInst(Predicate, LHS, RHS, TD);
+}
+

lib/Transforms/Scalar/InstructionCombining.cpp

@@ -42,6 +42,7 @@
 #include "llvm/GlobalVariable.h"
 #include "llvm/Operator.h"
 #include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/Target/TargetData.h"

lib/Transforms/Scalar/JumpThreading.cpp

@@ -354,7 +354,7 @@ ComputeValueKnownInPredecessors(Value *V, BasicBlock *BB,PredValueInfo &Result){
         Value *LHS = PN->getIncomingValue(i);
         Value *RHS = Cmp->getOperand(1)->DoPHITranslation(BB, PredBB);
         
-        Value *Res = SimplifyCompare(Cmp->getPredicate(), LHS, RHS);
+        Value *Res = SimplifyCmpInst(Cmp->getPredicate(), LHS, RHS);
         if (Res == 0) continue;
         
         if (isa<UndefValue>(Res))