TTI: Honour cost model for estimating cost of vector-intrinsic and calls.

[oota-llvm.git] / include / llvm / CodeGen / BasicTTIImpl.h

diff --git a/include/llvm/CodeGen/BasicTTIImpl.h b/include/llvm/CodeGen/BasicTTIImpl.h
index 61664327244faabe1b43240e11553e6ee9ac1602..4b80c4824922f528b9899597ca7c13a8d366c4af 100644 (file)
--- a/include/llvm/CodeGen/BasicTTIImpl.h
+++ b/include/llvm/CodeGen/BasicTTIImpl.h
@@ -21,6 +21,7 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Target/TargetLowering.h"
 #include "llvm/Target/TargetSubtargetInfo.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
 
 namespace llvm {
 
@@ -145,11 +146,37 @@ public:
     return getTLI()->isTruncateFree(Ty1, Ty2);
   }
 
+  bool isProfitableToHoist(Instruction *I) {
+    return getTLI()->isProfitableToHoist(I);
+  }
+
   bool isTypeLegal(Type *Ty) {
     EVT VT = getTLI()->getValueType(Ty);
     return getTLI()->isTypeLegal(VT);
   }
 
+  unsigned getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
+                            ArrayRef<const Value *> Arguments) {
+    return BaseT::getIntrinsicCost(IID, RetTy, Arguments);
+  }
+
+  unsigned getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
+                            ArrayRef<Type *> ParamTys) {
+    if (IID == Intrinsic::cttz) {
+      if (getTLI()->isCheapToSpeculateCttz())
+        return TargetTransformInfo::TCC_Basic;
+      return TargetTransformInfo::TCC_Expensive;
+    }
+
+    if (IID == Intrinsic::ctlz) {
+       if (getTLI()->isCheapToSpeculateCtlz())
+        return TargetTransformInfo::TCC_Basic;
+      return TargetTransformInfo::TCC_Expensive;
+    }
+
+    return BaseT::getIntrinsicCost(IID, RetTy, ParamTys);
+  }
+
   unsigned getJumpBufAlignment() { return getTLI()->getJumpBufAlignment(); }
 
   unsigned getJumpBufSize() { return getTLI()->getJumpBufSize(); }
@@ -167,6 +194,31 @@ public:
            TLI->isOperationLegalOrCustom(ISD::FSQRT, VT);
   }
 
+  unsigned getFPOpCost(Type *Ty) {
+    // By default, FP instructions are no more expensive since they are
+    // implemented in HW.  Target specific TTI can override this.
+    return TargetTransformInfo::TCC_Basic;
+  }
+
+  unsigned getOperationCost(unsigned Opcode, Type *Ty, Type *OpTy) {
+    const TargetLoweringBase *TLI = getTLI();
+    switch (Opcode) {
+    default: break;
+    case Instruction::Trunc: {
+      if (TLI->isTruncateFree(OpTy, Ty))
+        return TargetTransformInfo::TCC_Free;
+      return TargetTransformInfo::TCC_Basic;
+    }
+    case Instruction::ZExt: {
+      if (TLI->isZExtFree(OpTy, Ty))
+        return TargetTransformInfo::TCC_Free;
+      return TargetTransformInfo::TCC_Basic;
+    }
+    }
+
+    return BaseT::getOperationCost(Opcode, Ty, OpTy);
+  }
+
   void getUnrollingPreferences(Loop *L, TTI::UnrollingPreferences &UP) {
     // This unrolling functionality is target independent, but to provide some
     // motivation for its intended use, for x86:
@@ -476,18 +528,29 @@ public:
       // Assume that we need to scalarize this intrinsic.
       unsigned ScalarizationCost = 0;
       unsigned ScalarCalls = 1;
+      Type *ScalarRetTy = RetTy;
       if (RetTy->isVectorTy()) {
         ScalarizationCost = getScalarizationOverhead(RetTy, true, false);
         ScalarCalls = std::max(ScalarCalls, RetTy->getVectorNumElements());
+        ScalarRetTy = RetTy->getScalarType();
       }
+      SmallVector<Type *, 4> ScalarTys;
       for (unsigned i = 0, ie = Tys.size(); i != ie; ++i) {
-        if (Tys[i]->isVectorTy()) {
-          ScalarizationCost += getScalarizationOverhead(Tys[i], false, true);
-          ScalarCalls = std::max(ScalarCalls, RetTy->getVectorNumElements());
+        Type *Ty = Tys[i];
+        if (Ty->isVectorTy()) {
+          ScalarizationCost += getScalarizationOverhead(Ty, false, true);
+          ScalarCalls = std::max(ScalarCalls, Ty->getVectorNumElements());
+          Ty = Ty->getScalarType();
         }
+        ScalarTys.push_back(Ty);
       }
+      if (ScalarCalls == 1)
+        return 1; // Return cost of a scalar intrinsic. Assume it to be cheap.
 
-      return ScalarCalls + ScalarizationCost;
+      unsigned ScalarCost = static_cast<T *>(this)->getIntrinsicInstrCost(
+          IID, ScalarRetTy, ScalarTys);
+
+      return ScalarCalls * ScalarCost + ScalarizationCost;
     }
     // Look for intrinsics that can be lowered directly or turned into a scalar
     // intrinsic call.
@@ -597,16 +660,45 @@ public:
     // this will emit a costly libcall, adding call overhead and spills. Make it
     // very expensive.
     if (RetTy->isVectorTy()) {
-      unsigned Num = RetTy->getVectorNumElements();
-      unsigned Cost = static_cast<T *>(this)->getIntrinsicInstrCost(
-          IID, RetTy->getScalarType(), Tys);
-      return 10 * Cost * Num;
+      unsigned ScalarizationCost = getScalarizationOverhead(RetTy, true, false);
+      unsigned ScalarCalls = RetTy->getVectorNumElements();
+      SmallVector<Type *, 4> ScalarTys;
+      for (unsigned i = 0, ie = Tys.size(); i != ie; ++i) {
+        Type *Ty = Tys[i];
+        if (Ty->isVectorTy())
+          Ty = Ty->getScalarType();
+        ScalarTys.push_back(Ty);
+      }
+      unsigned ScalarCost = static_cast<T *>(this)->getIntrinsicInstrCost(
+          IID, RetTy->getScalarType(), ScalarTys);
+      for (unsigned i = 0, ie = Tys.size(); i != ie; ++i) {
+        if (Tys[i]->isVectorTy()) {
+          ScalarizationCost += getScalarizationOverhead(Tys[i], false, true);
+          ScalarCalls = std::max(ScalarCalls, Tys[i]->getVectorNumElements());
+        }
+      }
+
+      return ScalarCalls * ScalarCost + ScalarizationCost;
     }
 
     // This is going to be turned into a library call, make it expensive.
     return 10;
   }
 
+  /// \brief Compute a cost of the given call instruction.
+  ///
+  /// Compute the cost of calling function F with return type RetTy and
+  /// argument types Tys. F might be nullptr, in this case the cost of an
+  /// arbitrary call with the specified signature will be returned.
+  /// This is used, for instance,  when we estimate call of a vector
+  /// counterpart of the given function.
+  /// \param F Called function, might be nullptr.
+  /// \param RetTy,Tys Return value and argument types.
+  /// \returns The cost of Call instruction.
+  unsigned getCallInstrCost(Function *F, Type *RetTy, ArrayRef<Type *> Tys) {
+    return 10;
+  }
+
   unsigned getNumberOfParts(Type *Tp) {
     std::pair<unsigned, MVT> LT = getTLI()->getTypeLegalizationCost(Tp);
     return LT.first;