-//===- InlineCost.cpp - Cost analysis for inliner ---------------*- C++ -*-===//
+//===- InlineCost.h - Cost analysis for inliner -----------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
#include <cassert>
#include <climits>
-#include <map>
#include <vector>
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/ValueMap.h"
+#include "llvm/Analysis/CodeMetrics.h"
namespace llvm {
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;
-
- /// NumCalls - Keep track of the number of calls to 'big' functions.
- unsigned NumCalls;
-
- /// 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), NumCalls(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 InstrCost = 5;
public:
unsigned ConstantWeight;
unsigned AllocaWeight;
+ unsigned ConstantBonus;
- ArgInfo(unsigned CWeight, unsigned AWeight)
- : ConstantWeight(CWeight), AllocaWeight(AWeight) {}
+ ArgInfo(unsigned CWeight, unsigned AWeight, unsigned CBonus)
+ : ConstantWeight(CWeight), AllocaWeight(AWeight), ConstantBonus(CBonus)
+ {}
};
struct FunctionInfo {
/// 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);
+
+ /// NeverInline - Returns true if the function should never be
+ /// inlined into any caller.
+ bool NeverInline();
};
- std::map<const Function *, FunctionInfo> CachedFunctionInfo;
+ // The Function* for a function can be changed (by ArgumentPromotion);
+ // the ValueMap will update itself when this happens.
+ ValueMap<const Function *, FunctionInfo> CachedFunctionInfo;
public:
///
InlineCost getInlineCost(CallSite CS,
SmallPtrSet<const Function *, 16> &NeverInline);
+ /// getCalledFunction - The heuristic used to determine if we should inline
+ /// the function call or not. The callee is explicitly specified, to allow
+ /// you to calculate the cost of inlining a function via a pointer. The
+ /// result assumes that the inlined version will always be used. You should
+ /// weight it yourself in cases where this callee will not always be called.
+ InlineCost getInlineCost(CallSite CS,
+ Function *Callee,
+ SmallPtrSet<const Function *, 16> &NeverInline);
+
+ /// getSpecializationBonus - The heuristic used to determine the per-call
+ /// performance boost for using a specialization of Callee with argument
+ /// SpecializedArgNos replaced by a constant.
+ int getSpecializationBonus(Function *Callee,
+ SmallVectorImpl<unsigned> &SpecializedArgNo);
+
+ /// getSpecializationCost - The heuristic used to determine the code-size
+ /// impact of creating a specialized version of Callee with argument
+ /// SpecializedArgNo replaced by a constant.
+ InlineCost getSpecializationCost(Function *Callee,
+ SmallVectorImpl<unsigned> &SpecializedArgNo);
/// getInlineFudgeFactor - Return a > 1.0 factor if the inliner should use a
/// higher threshold to determine if the function call should be inlined.
/// has been inlined. If Callee is NULL it means a dead call has been
/// eliminated.
void growCachedCostInfo(Function* Caller, Function* Callee);
+
+ /// clear - empty the cache of inline costs
+ void clear();
};
+
+ /// callIsSmall - If a call is likely to lower to a single target instruction,
+ /// or is otherwise deemed small return true.
+ bool callIsSmall(const Function *Callee);
}
#endif