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diff --git a/include/llvm/Analysis/InlineCost.h b/include/llvm/Analysis/InlineCost.h
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+//===- InlineCost.cpp - Cost analysis for inliner ---------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements heuristics for inlining decisions.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_INLINECOST_H
+#define LLVM_ANALYSIS_INLINECOST_H
+
+#include <cassert>
+#include <climits>
+#include <map>
+#include <vector>
+
+namespace llvm {
+
+  class Value;
+  class Function;
+  class BasicBlock;
+  class CallSite;
+  template<class PtrType, unsigned SmallSize>
+  class SmallPtrSet;
+
+  // CodeMetrics - Calculate size and a few similar metrics for a set of
+  // basic blocks.
+  struct CodeMetrics {
+    /// NeverInline - True if this callee should never be inlined into a
+    /// caller.
+    bool NeverInline;
+    
+    /// usesDynamicAlloca - True if this function calls alloca (in the C sense).
+    bool usesDynamicAlloca;
+
+    /// NumInsts, NumBlocks - Keep track of how large each function is, which
+    /// is used to estimate the code size cost of inlining it.
+    unsigned NumInsts, NumBlocks;
+
+    /// NumVectorInsts - Keep track of how many instructions produce vector
+    /// values.  The inliner is being more aggressive with inlining vector
+    /// kernels.
+    unsigned NumVectorInsts;
+    
+    /// NumRets - Keep track of how many Ret instructions the block contains.
+    unsigned NumRets;
+
+    CodeMetrics() : NeverInline(false), usesDynamicAlloca(false), NumInsts(0),
+                    NumBlocks(0), NumVectorInsts(0), NumRets(0) {}
+    
+    /// analyzeBasicBlock - Add information about the specified basic block
+    /// to the current structure.
+    void analyzeBasicBlock(const BasicBlock *BB);
+
+    /// analyzeFunction - Add information about the specified function
+    /// to the current structure.
+    void analyzeFunction(Function *F);
+  };
+
+  namespace InlineConstants {
+    // Various magic constants used to adjust heuristics.
+    const int CallPenalty = 5;
+    const int LastCallToStaticBonus = -15000;
+    const int ColdccPenalty = 2000;
+    const int NoreturnPenalty = 10000;
+  }
+
+  /// InlineCost - Represent the cost of inlining a function. This
+  /// supports special values for functions which should "always" or
+  /// "never" be inlined. Otherwise, the cost represents a unitless
+  /// amount; smaller values increase the likelyhood of the function
+  /// being inlined.
+  class InlineCost {
+    enum Kind {
+      Value,
+      Always,
+      Never
+    };
+
+    // This is a do-it-yourself implementation of
+    //   int Cost : 30;
+    //   unsigned Type : 2;
+    // We used to use bitfields, but they were sometimes miscompiled (PR3822).
+    enum { TYPE_BITS = 2 };
+    enum { COST_BITS = unsigned(sizeof(unsigned)) * CHAR_BIT - TYPE_BITS };
+    unsigned TypedCost; // int Cost : COST_BITS; unsigned Type : TYPE_BITS;
+
+    Kind getType() const {
+      return Kind(TypedCost >> COST_BITS);
+    }
+
+    int getCost() const {
+      // Sign-extend the bottom COST_BITS bits.
+      return (int(TypedCost << TYPE_BITS)) >> TYPE_BITS;
+    }
+
+    InlineCost(int C, int T) {
+      TypedCost = (unsigned(C << TYPE_BITS) >> TYPE_BITS) | (T << COST_BITS);
+      assert(getCost() == C && "Cost exceeds InlineCost precision");
+    }
+  public:
+    static InlineCost get(int Cost) { return InlineCost(Cost, Value); }
+    static InlineCost getAlways() { return InlineCost(0, Always); }
+    static InlineCost getNever() { return InlineCost(0, Never); }
+
+    bool isVariable() const { return getType() == Value; }
+    bool isAlways() const { return getType() == Always; }
+    bool isNever() const { return getType() == Never; }
+
+    /// getValue() - Return a "variable" inline cost's amount. It is
+    /// an error to call this on an "always" or "never" InlineCost.
+    int getValue() const {
+      assert(getType() == Value && "Invalid access of InlineCost");
+      return getCost();
+    }
+  };
+  
+  /// InlineCostAnalyzer - Cost analyzer used by inliner.
+  class InlineCostAnalyzer {
+    struct ArgInfo {
+    public:
+      unsigned ConstantWeight;
+      unsigned AllocaWeight;
+      
+      ArgInfo(unsigned CWeight, unsigned AWeight)
+        : ConstantWeight(CWeight), AllocaWeight(AWeight) {}
+    };
+    
+    struct FunctionInfo {
+      CodeMetrics Metrics;
+
+      /// ArgumentWeights - Each formal argument of the function is inspected to
+      /// see if it is used in any contexts where making it a constant or alloca
+      /// would reduce the code size.  If so, we add some value to the argument
+      /// entry here.
+      std::vector<ArgInfo> ArgumentWeights;
+    
+      /// CountCodeReductionForConstant - Figure out an approximation for how
+      /// many instructions will be constant folded if the specified value is
+      /// constant.
+      unsigned CountCodeReductionForConstant(Value *V);
+    
+      /// CountCodeReductionForAlloca - Figure out an approximation of how much
+      /// smaller the function will be if it is inlined into a context where an
+      /// argument becomes an alloca.
+      ///
+      unsigned CountCodeReductionForAlloca(Value *V);
+
+      /// analyzeFunction - Add information about the specified function
+      /// to the current structure.
+      void analyzeFunction(Function *F);
+    };
+
+    std::map<const Function *, FunctionInfo> CachedFunctionInfo;
+
+  public:
+
+    /// getInlineCost - The heuristic used to determine if we should inline the
+    /// function call or not.
+    ///
+    InlineCost getInlineCost(CallSite CS,
+                             SmallPtrSet<const Function *, 16> &NeverInline);
+
+    /// getInlineFudgeFactor - Return a > 1.0 factor if the inliner should use a
+    /// higher threshold to determine if the function call should be inlined.
+    float getInlineFudgeFactor(CallSite CS);
+
+    /// resetCachedFunctionInfo - erase any cached cost info for this function.
+    void resetCachedCostInfo(Function* Caller) {
+      CachedFunctionInfo[Caller] = FunctionInfo();
+    }
+  };
+}
+
+#endif