diff options
Diffstat (limited to 'lib/Transforms/IPO/Inliner.cpp')
-rw-r--r-- | lib/Transforms/IPO/Inliner.cpp | 70 |
1 files changed, 60 insertions, 10 deletions
diff --git a/lib/Transforms/IPO/Inliner.cpp b/lib/Transforms/IPO/Inliner.cpp index e97fb834f8..9087ab23bb 100644 --- a/lib/Transforms/IPO/Inliner.cpp +++ b/lib/Transforms/IPO/Inliner.cpp @@ -13,7 +13,6 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "inline" #include "llvm/Transforms/IPO/InlinerPass.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/Statistic.h" @@ -21,6 +20,7 @@ #include "llvm/Analysis/InlineCost.h" #include "llvm/IR/CallSite.h" #include "llvm/IR/DataLayout.h" +#include "llvm/IR/DiagnosticInfo.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/IntrinsicInst.h" #include "llvm/IR/Module.h" @@ -32,6 +32,8 @@ #include "llvm/Transforms/Utils/Local.h" using namespace llvm; +#define DEBUG_TYPE "inline" + STATISTIC(NumInlined, "Number of functions inlined"); STATISTIC(NumCallsDeleted, "Number of call sites deleted, not inlined"); STATISTIC(NumDeleted, "Number of functions deleted because all callers found"); @@ -183,7 +185,7 @@ static bool InlineCallIfPossible(CallSite CS, InlineFunctionInfo &IFI, // canonicalized to be an allocation *of* an array), or allocations whose // type is not itself an array (because we're afraid of pessimizing SRoA). ArrayType *ATy = dyn_cast<ArrayType>(AI->getAllocatedType()); - if (ATy == 0 || AI->isArrayAllocation()) + if (!ATy || AI->isArrayAllocation()) continue; // Get the list of all available allocas for this array type. @@ -239,7 +241,7 @@ static bool InlineCallIfPossible(CallSite CS, InlineFunctionInfo &IFI, AI->eraseFromParent(); MergedAwayAlloca = true; ++NumMergedAllocas; - IFI.StaticAllocas[AllocaNo] = 0; + IFI.StaticAllocas[AllocaNo] = nullptr; break; } @@ -288,12 +290,24 @@ unsigned Inliner::getInlineThreshold(CallSite CS) const { bool ColdCallee = Callee && !Callee->isDeclaration() && Callee->getAttributes().hasAttribute(AttributeSet::FunctionIndex, Attribute::Cold); - if (ColdCallee && ColdThreshold < thres) + // Command line argument for InlineLimit will override the default + // ColdThreshold. If we have -inline-threshold but no -inlinecold-threshold, + // do not use the default cold threshold even if it is smaller. + if ((InlineLimit.getNumOccurrences() == 0 || + ColdThreshold.getNumOccurrences() > 0) && ColdCallee && + ColdThreshold < thres) thres = ColdThreshold; return thres; } +static void emitAnalysis(CallSite CS, const Twine &Msg) { + Function *Caller = CS.getCaller(); + LLVMContext &Ctx = Caller->getContext(); + DebugLoc DLoc = CS.getInstruction()->getDebugLoc(); + emitOptimizationRemarkAnalysis(Ctx, DEBUG_TYPE, *Caller, DLoc, Msg); +} + /// shouldInline - Return true if the inliner should attempt to inline /// at the given CallSite. bool Inliner::shouldInline(CallSite CS) { @@ -302,12 +316,16 @@ bool Inliner::shouldInline(CallSite CS) { if (IC.isAlways()) { DEBUG(dbgs() << " Inlining: cost=always" << ", Call: " << *CS.getInstruction() << "\n"); + emitAnalysis(CS, Twine(CS.getCalledFunction()->getName()) + + " should always be inlined (cost=always)"); return true; } if (IC.isNever()) { DEBUG(dbgs() << " NOT Inlining: cost=never" << ", Call: " << *CS.getInstruction() << "\n"); + emitAnalysis(CS, Twine(CS.getCalledFunction()->getName() + + " should never be inlined (cost=never)")); return false; } @@ -316,6 +334,10 @@ bool Inliner::shouldInline(CallSite CS) { DEBUG(dbgs() << " NOT Inlining: cost=" << IC.getCost() << ", thres=" << (IC.getCostDelta() + IC.getCost()) << ", Call: " << *CS.getInstruction() << "\n"); + emitAnalysis(CS, Twine(CS.getCalledFunction()->getName() + + " too costly to inline (cost=") + + Twine(IC.getCost()) + ", threshold=" + + Twine(IC.getCostDelta() + IC.getCost()) + ")"); return false; } @@ -383,6 +405,11 @@ bool Inliner::shouldInline(CallSite CS) { DEBUG(dbgs() << " NOT Inlining: " << *CS.getInstruction() << " Cost = " << IC.getCost() << ", outer Cost = " << TotalSecondaryCost << '\n'); + emitAnalysis( + CS, Twine("Not inlining. Cost of inlining " + + CS.getCalledFunction()->getName() + + " increases the cost of inlining " + + CS.getCaller()->getName() + " in other contexts")); return false; } } @@ -390,6 +417,10 @@ bool Inliner::shouldInline(CallSite CS) { DEBUG(dbgs() << " Inlining: cost=" << IC.getCost() << ", thres=" << (IC.getCostDelta() + IC.getCost()) << ", Call: " << *CS.getInstruction() << '\n'); + emitAnalysis( + CS, CS.getCalledFunction()->getName() + Twine(" can be inlined into ") + + CS.getCaller()->getName() + " with cost=" + Twine(IC.getCost()) + + " (threshold=" + Twine(IC.getCostDelta() + IC.getCost()) + ")"); return true; } @@ -410,7 +441,7 @@ static bool InlineHistoryIncludes(Function *F, int InlineHistoryID, bool Inliner::runOnSCC(CallGraphSCC &SCC) { CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph(); DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>(); - const DataLayout *DL = DLP ? &DLP->getDataLayout() : 0; + const DataLayout *DL = DLP ? &DLP->getDataLayout() : nullptr; const TargetLibraryInfo *TLI = getAnalysisIfAvailable<TargetLibraryInfo>(); SmallPtrSet<Function*, 8> SCCFunctions; @@ -499,7 +530,7 @@ bool Inliner::runOnSCC(CallGraphSCC &SCC) { ++NumCallsDeleted; } else { // We can only inline direct calls to non-declarations. - if (Callee == 0 || Callee->isDeclaration()) continue; + if (!Callee || Callee->isDeclaration()) continue; // If this call site was obtained by inlining another function, verify // that the include path for the function did not include the callee @@ -511,18 +542,37 @@ bool Inliner::runOnSCC(CallGraphSCC &SCC) { InlineHistoryIncludes(Callee, InlineHistoryID, InlineHistory)) continue; - + LLVMContext &CallerCtx = Caller->getContext(); + + // Get DebugLoc to report. CS will be invalid after Inliner. + DebugLoc DLoc = CS.getInstruction()->getDebugLoc(); + // If the policy determines that we should inline this function, // try to do so. - if (!shouldInline(CS)) + if (!shouldInline(CS)) { + emitOptimizationRemarkMissed(CallerCtx, DEBUG_TYPE, *Caller, DLoc, + Twine(Callee->getName() + + " will not be inlined into " + + Caller->getName())); continue; + } // Attempt to inline the function. if (!InlineCallIfPossible(CS, InlineInfo, InlinedArrayAllocas, - InlineHistoryID, InsertLifetime, DL)) + InlineHistoryID, InsertLifetime, DL)) { + emitOptimizationRemarkMissed(CallerCtx, DEBUG_TYPE, *Caller, DLoc, + Twine(Callee->getName() + + " will not be inlined into " + + Caller->getName())); continue; + } ++NumInlined; - + + // Report the inline decision. + emitOptimizationRemark( + CallerCtx, DEBUG_TYPE, *Caller, DLoc, + Twine(Callee->getName() + " inlined into " + Caller->getName())); + // If inlining this function gave us any new call sites, throw them // onto our worklist to process. They are useful inline candidates. if (!InlineInfo.InlinedCalls.empty()) { |