-//===- CodeMetrics.h - Measures the weight of a function---------*- C++ -*-===//
+//===- CodeMetrics.h - Code cost measurements -------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
//
-// This file implements various weight measurements for a function, helping
-// the Inliner and PartialSpecialization decide whether to duplicate its
-// contents.
+// This file implements various weight measurements for code, helping
+// the Inliner and other passes decide whether to duplicate its contents.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_CODEMETRICS_H
#define LLVM_ANALYSIS_CODEMETRICS_H
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/IR/CallSite.h"
+
namespace llvm {
- // 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;
-
- // True if this function contains a call to setjmp or _setjmp
- bool callsSetJmp;
-
- // True if this function calls itself
- bool isRecursive;
-
- // True if this function contains one or more indirect branches
- bool containsIndirectBr;
-
- /// 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;
-
- /// NumBBInsts - Keeps track of basic block code size estimates.
- DenseMap<const BasicBlock *, unsigned> NumBBInsts;
-
- /// NumCalls - Keep track of the number of calls to 'big' functions.
- unsigned NumCalls;
-
- /// NumInlineCandidates - Keep track of the number of calls to internal
- /// functions with only a single caller. These are likely targets for
- /// future inlining, likely exposed by interleaved devirtualization.
- unsigned NumInlineCandidates;
-
- /// 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() : callsSetJmp(false), isRecursive(false),
- containsIndirectBr(false), usesDynamicAlloca(false),
- NumInsts(0), NumBlocks(0), NumCalls(0),
- NumInlineCandidates(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);
-
- /// 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);
- };
+class AssumptionCache;
+class BasicBlock;
+class Loop;
+class Function;
+class Instruction;
+class DataLayout;
+class TargetTransformInfo;
+class Value;
+
+/// \brief Check whether a call will lower to something small.
+///
+/// This tests checks whether this callsite will lower to something
+/// significantly cheaper than a traditional call, often a single
+/// instruction. Note that if isInstructionFree(CS.getInstruction()) would
+/// return true, so will this function.
+bool callIsSmall(ImmutableCallSite CS);
+
+/// \brief Utility to calculate the size and a few similar metrics for a set
+/// of basic blocks.
+struct CodeMetrics {
+ /// \brief True if this function contains a call to setjmp or other functions
+ /// with attribute "returns twice" without having the attribute itself.
+ bool exposesReturnsTwice;
+
+ /// \brief True if this function calls itself.
+ bool isRecursive;
+
+ /// \brief True if this function cannot be duplicated.
+ ///
+ /// True if this function contains one or more indirect branches, or it contains
+ /// one or more 'noduplicate' instructions.
+ bool notDuplicatable;
+
+ /// \brief True if this function calls alloca (in the C sense).
+ bool usesDynamicAlloca;
+
+ /// \brief Number of instructions in the analyzed blocks.
+ unsigned NumInsts;
+
+ /// \brief Number of analyzed blocks.
+ unsigned NumBlocks;
+
+ /// \brief Keeps track of basic block code size estimates.
+ DenseMap<const BasicBlock *, unsigned> NumBBInsts;
+
+ /// \brief Keep track of the number of calls to 'big' functions.
+ unsigned NumCalls;
+
+ /// \brief The number of calls to internal functions with a single caller.
+ ///
+ /// These are likely targets for future inlining, likely exposed by
+ /// interleaved devirtualization.
+ unsigned NumInlineCandidates;
+
+ /// \brief How many instructions produce vector values.
+ ///
+ /// The inliner is more aggressive with inlining vector kernels.
+ unsigned NumVectorInsts;
+
+ /// \brief How many 'ret' instructions the blocks contain.
+ unsigned NumRets;
+
+ CodeMetrics()
+ : exposesReturnsTwice(false), isRecursive(false), notDuplicatable(false),
+ usesDynamicAlloca(false), NumInsts(0), NumBlocks(0), NumCalls(0),
+ NumInlineCandidates(0), NumVectorInsts(0), NumRets(0) {}
+
+ /// \brief Add information about a block to the current state.
+ void analyzeBasicBlock(const BasicBlock *BB, const TargetTransformInfo &TTI,
+ SmallPtrSetImpl<const Value*> &EphValues);
+
+ /// \brief Collect a loop's ephemeral values (those used only by an assume
+ /// or similar intrinsics in the loop).
+ static void collectEphemeralValues(const Loop *L, AssumptionCache *AC,
+ SmallPtrSetImpl<const Value *> &EphValues);
+
+ /// \brief Collect a functions's ephemeral values (those used only by an
+ /// assume or similar intrinsics in the function).
+ static void collectEphemeralValues(const Function *L, AssumptionCache *AC,
+ SmallPtrSetImpl<const Value *> &EphValues);
+};
+
}
#endif
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