1cf5933a716e7eb6bd5ff49aa62f3e76379ebaf51Chris Lattner//===- Inliner.cpp - Code common to all inliners --------------------------===// 2fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman// 3b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// The LLVM Compiler Infrastructure 4b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// 54ee451de366474b9c228b4e5fa573795a715216dChris Lattner// This file is distributed under the University of Illinois Open Source 64ee451de366474b9c228b4e5fa573795a715216dChris Lattner// License. See LICENSE.TXT for details. 7fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman// 8b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell//===----------------------------------------------------------------------===// 9237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner// 10befa499d45ffcc32bd9902518aec18589464e47cChris Lattner// This file implements the mechanics required to implement inlining without 11befa499d45ffcc32bd9902518aec18589464e47cChris Lattner// missing any calls and updating the call graph. The decisions of which calls 12befa499d45ffcc32bd9902518aec18589464e47cChris Lattner// are profitable to inline are implemented elsewhere. 13237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner// 14237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner//===----------------------------------------------------------------------===// 15237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner 1686453c52ba02e743d29c08456e51006500041456Chris Lattner#define DEBUG_TYPE "inline" 17d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/Transforms/IPO/InlinerPass.h" 18d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/ADT/SmallPtrSet.h" 19d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/ADT/Statistic.h" 20237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner#include "llvm/Analysis/CallGraph.h" 21e4aeec003f82a5263ffb168e175e6fca8b6f681dDan Gohman#include "llvm/Analysis/InlineCost.h" 220b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/DataLayout.h" 230b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/Instructions.h" 240b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/IntrinsicInst.h" 250b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/Module.h" 264ff4141a9ee9ce705f2a709f3372acaf58d86ea3Chris Lattner#include "llvm/Support/CallSite.h" 27551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#include "llvm/Support/CommandLine.h" 28551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#include "llvm/Support/Debug.h" 29ce63ffb52f249b62cdf2d250c128007b13f27e71Daniel Dunbar#include "llvm/Support/raw_ostream.h" 30d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/Target/TargetLibraryInfo.h" 31d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/Transforms/Utils/Cloning.h" 32d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/Transforms/Utils/Local.h" 33a51bcb50b0c74adc741361824ef81dbefb715c53Chris Lattnerusing namespace llvm; 34d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 3586453c52ba02e743d29c08456e51006500041456Chris LattnerSTATISTIC(NumInlined, "Number of functions inlined"); 3683f66fe6144c2041f1f7897f7015b0e2e68faad3Chris LattnerSTATISTIC(NumCallsDeleted, "Number of call sites deleted, not inlined"); 3786453c52ba02e743d29c08456e51006500041456Chris LattnerSTATISTIC(NumDeleted, "Number of functions deleted because all callers found"); 38199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris LattnerSTATISTIC(NumMergedAllocas, "Number of allocas merged together"); 3986453c52ba02e743d29c08456e51006500041456Chris Lattner 40d9b0b025612992a0b724eeca8bdf10b1d7a5c355Benjamin Kramer// This weirdly named statistic tracks the number of times that, when attempting 41d6fc26217e194372cabe4ef9e2514beac511a943Chandler Carruth// to inline a function A into B, we analyze the callers of B in order to see 42d6fc26217e194372cabe4ef9e2514beac511a943Chandler Carruth// if those would be more profitable and blocked inline steps. 43d6fc26217e194372cabe4ef9e2514beac511a943Chandler CarruthSTATISTIC(NumCallerCallersAnalyzed, "Number of caller-callers analyzed"); 44d6fc26217e194372cabe4ef9e2514beac511a943Chandler Carruth 45844731a7f1909f55935e3514c9e713a62d67662eDan Gohmanstatic cl::opt<int> 46f9c3b228e5579e0d2a9cd05a2191fe17b4c58b23Jakob Stoklund OlesenInlineLimit("inline-threshold", cl::Hidden, cl::init(225), cl::ZeroOrMore, 47f9c3b228e5579e0d2a9cd05a2191fe17b4c58b23Jakob Stoklund Olesen cl::desc("Control the amount of inlining to perform (default = 225)")); 48237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner 49f0907fe59093753fe5a9e8fe5adc399dbdc94627Jakob Stoklund Olesenstatic cl::opt<int> 50f0907fe59093753fe5a9e8fe5adc399dbdc94627Jakob Stoklund OlesenHintThreshold("inlinehint-threshold", cl::Hidden, cl::init(325), 51f0907fe59093753fe5a9e8fe5adc399dbdc94627Jakob Stoklund Olesen cl::desc("Threshold for inlining functions with inline hint")); 52570a4a5d9ca31f276a67502d1e0533d59d331feaJakob Stoklund Olesen 53570a4a5d9ca31f276a67502d1e0533d59d331feaJakob Stoklund Olesen// Threshold to use when optsize is specified (and there is no -inline-limit). 54570a4a5d9ca31f276a67502d1e0533d59d331feaJakob Stoklund Olesenconst int OptSizeThreshold = 75; 55570a4a5d9ca31f276a67502d1e0533d59d331feaJakob Stoklund Olesen 5690c579de5a383cee278acc3f7e7b9d0a656e6a35Owen AndersonInliner::Inliner(char &ID) 57fa086f1f00a8b75ab2e2208bd7a028e62f9854dbChad Rosier : CallGraphSCCPass(ID), InlineThreshold(InlineLimit), InsertLifetime(true) {} 58237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner 59fa086f1f00a8b75ab2e2208bd7a028e62f9854dbChad RosierInliner::Inliner(char &ID, int Threshold, bool InsertLifetime) 60930f5efac0f76aa9e3772d9a36757f18b3573112Jakob Stoklund Olesen : CallGraphSCCPass(ID), InlineThreshold(InlineLimit.getNumOccurrences() > 0 ? 61fa086f1f00a8b75ab2e2208bd7a028e62f9854dbChad Rosier InlineLimit : Threshold), 62fa086f1f00a8b75ab2e2208bd7a028e62f9854dbChad Rosier InsertLifetime(InsertLifetime) {} 63120d053e3ba810b44047fbcb719824bed5673ca9Chris Lattner 64ff2dad312883e5da91fb9f4e3619b7d095867f3bChris Lattner/// getAnalysisUsage - For this class, we declare that we require and preserve 65ff2dad312883e5da91fb9f4e3619b7d095867f3bChris Lattner/// the call graph. If the derived class implements this method, it should 66ff2dad312883e5da91fb9f4e3619b7d095867f3bChris Lattner/// always explicitly call the implementation here. 677ccc2f7a7859a72ce73e6d8dc4242c6dd7984c45Chandler Carruthvoid Inliner::getAnalysisUsage(AnalysisUsage &AU) const { 687ccc2f7a7859a72ce73e6d8dc4242c6dd7984c45Chandler Carruth CallGraphSCCPass::getAnalysisUsage(AU); 69ff2dad312883e5da91fb9f4e3619b7d095867f3bChris Lattner} 70ff2dad312883e5da91fb9f4e3619b7d095867f3bChris Lattner 71199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 72db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattnertypedef DenseMap<ArrayType*, std::vector<AllocaInst*> > 73199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris LattnerInlinedArrayAllocasTy; 74199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 75114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling/// \brief If the inlined function had a higher stack protection level than the 76114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling/// calling function, then bump up the caller's stack protection level. 77114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendlingstatic void AdjustCallerSSPLevel(Function *Caller, Function *Callee) { 78114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling // If upgrading the SSP attribute, clear out the old SSP Attributes first. 79114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling // Having multiple SSP attributes doesn't actually hurt, but it adds useless 80114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling // clutter to the IR. 81114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling AttrBuilder B; 82114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling B.addAttribute(Attribute::StackProtect) 83114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling .addAttribute(Attribute::StackProtectStrong); 84114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling AttributeSet OldSSPAttr = AttributeSet::get(Caller->getContext(), 85114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling AttributeSet::FunctionIndex, 86114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling B); 87114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling AttributeSet CallerAttr = Caller->getAttributes(), 88114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling CalleeAttr = Callee->getAttributes(); 89114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling 90114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling if (CalleeAttr.hasAttribute(AttributeSet::FunctionIndex, 91114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Attribute::StackProtectReq)) { 92114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Caller->removeAttributes(AttributeSet::FunctionIndex, OldSSPAttr); 93114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Caller->addFnAttr(Attribute::StackProtectReq); 94114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling } else if (CalleeAttr.hasAttribute(AttributeSet::FunctionIndex, 95114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Attribute::StackProtectStrong) && 96114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling !CallerAttr.hasAttribute(AttributeSet::FunctionIndex, 97114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Attribute::StackProtectReq)) { 98114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Caller->removeAttributes(AttributeSet::FunctionIndex, OldSSPAttr); 99114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Caller->addFnAttr(Attribute::StackProtectStrong); 100114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling } else if (CalleeAttr.hasAttribute(AttributeSet::FunctionIndex, 101114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Attribute::StackProtect) && 102114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling !CallerAttr.hasAttribute(AttributeSet::FunctionIndex, 103114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Attribute::StackProtectReq) && 104114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling !CallerAttr.hasAttribute(AttributeSet::FunctionIndex, 105114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Attribute::StackProtectStrong)) 106114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling Caller->addFnAttr(Attribute::StackProtect); 107114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling} 108114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling 109199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner/// InlineCallIfPossible - If it is possible to inline the specified call site, 110199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner/// do so and update the CallGraph for this operation. 111199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner/// 112199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner/// This function also does some basic book-keeping to update the IR. The 113cc0a0299d96676e0a51e9b8f5bf617d8025f09a7Chris Lattner/// InlinedArrayAllocas map keeps track of any allocas that are already 114cc0a0299d96676e0a51e9b8f5bf617d8025f09a7Chris Lattner/// available from other functions inlined into the caller. If we are able to 115cc0a0299d96676e0a51e9b8f5bf617d8025f09a7Chris Lattner/// inline this call site we attempt to reuse already available allocas or add 116cc0a0299d96676e0a51e9b8f5bf617d8025f09a7Chris Lattner/// any new allocas to the set if not possible. 11760915146f4d35e12f10dcdaa155596fac79184daChris Lattnerstatic bool InlineCallIfPossible(CallSite CS, InlineFunctionInfo &IFI, 1186c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner InlinedArrayAllocasTy &InlinedArrayAllocas, 1195a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel int InlineHistory, bool InsertLifetime, 1205a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel const DataLayout *TD) { 121befa499d45ffcc32bd9902518aec18589464e47cChris Lattner Function *Callee = CS.getCalledFunction(); 12266c75aaa028683c389c55b377ee2411b61081677Bill Wendling Function *Caller = CS.getCaller(); 12366c75aaa028683c389c55b377ee2411b61081677Bill Wendling 124199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Try to inline the function. Get the list of static allocas that were 125199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // inlined. 126fa086f1f00a8b75ab2e2208bd7a028e62f9854dbChad Rosier if (!InlineFunction(CS, IFI, InsertLifetime)) 12712f0babca4459c253675700e1d707652d5b6ba17Chris Lattner return false; 128fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 129114baee1fa017daefad2339c77b45b9ca3d79a41Bill Wendling AdjustCallerSSPLevel(Caller, Callee); 1308c1604e7d617622cb391f1c679ddf70ea03baedcBill Wendling 131199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Look at all of the allocas that we inlined through this call site. If we 132199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // have already inlined other allocas through other calls into this function, 133199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // then we know that they have disjoint lifetimes and that we can merge them. 134199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // 135199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // There are many heuristics possible for merging these allocas, and the 136199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // different options have different tradeoffs. One thing that we *really* 137199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // don't want to hurt is SRoA: once inlining happens, often allocas are no 138199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // longer address taken and so they can be promoted. 139199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // 140199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Our "solution" for that is to only merge allocas whose outermost type is an 141199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // array type. These are usually not promoted because someone is using a 142199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // variable index into them. These are also often the most important ones to 143199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // merge. 144199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // 145199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // A better solution would be to have real memory lifetime markers in the IR 146199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // and not have the inliner do any merging of allocas at all. This would 147199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // allow the backend to do proper stack slot coloring of all allocas that 148199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // *actually make it to the backend*, which is really what we want. 149199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // 150199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Because we don't have this information, we do this simple and useful hack. 151199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // 152199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner SmallPtrSet<AllocaInst*, 16> UsedAllocas; 153199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 1546c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // When processing our SCC, check to see if CS was inlined from some other 1556c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // call site. For example, if we're processing "A" in this code: 1566c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // A() { B() } 1576c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // B() { x = alloca ... C() } 1586c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // C() { y = alloca ... } 1596c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // Assume that C was not inlined into B initially, and so we're processing A 1606c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // and decide to inline B into A. Doing this makes an alloca available for 1616c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // reuse and makes a callsite (C) available for inlining. When we process 1626c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // the C call site we don't want to do any alloca merging between X and Y 1636c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // because their scopes are not disjoint. We could make this smarter by 1646c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // keeping track of the inline history for each alloca in the 1656c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner // InlinedArrayAllocas but this isn't likely to be a significant win. 1666c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner if (InlineHistory != -1) // Only do merging for top-level call sites in SCC. 1676c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner return true; 1686c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner 169199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Loop over all the allocas we have so far and see if they can be merged with 170199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // a previously inlined alloca. If not, remember that we had it. 17160915146f4d35e12f10dcdaa155596fac79184daChris Lattner for (unsigned AllocaNo = 0, e = IFI.StaticAllocas.size(); 172199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner AllocaNo != e; ++AllocaNo) { 17360915146f4d35e12f10dcdaa155596fac79184daChris Lattner AllocaInst *AI = IFI.StaticAllocas[AllocaNo]; 174199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 175199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Don't bother trying to merge array allocations (they will usually be 176199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // canonicalized to be an allocation *of* an array), or allocations whose 177199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // type is not itself an array (because we're afraid of pessimizing SRoA). 178db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner ArrayType *ATy = dyn_cast<ArrayType>(AI->getAllocatedType()); 179199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner if (ATy == 0 || AI->isArrayAllocation()) 180199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner continue; 181199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 182199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Get the list of all available allocas for this array type. 183199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner std::vector<AllocaInst*> &AllocasForType = InlinedArrayAllocas[ATy]; 184199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 185199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Loop over the allocas in AllocasForType to see if we can reuse one. Note 186199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // that we have to be careful not to reuse the same "available" alloca for 187199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // multiple different allocas that we just inlined, we use the 'UsedAllocas' 188199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // set to keep track of which "available" allocas are being used by this 189199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // function. Also, AllocasForType can be empty of course! 190199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner bool MergedAwayAlloca = false; 191199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner for (unsigned i = 0, e = AllocasForType.size(); i != e; ++i) { 192199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner AllocaInst *AvailableAlloca = AllocasForType[i]; 1935a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel 1945a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel unsigned Align1 = AI->getAlignment(), 1955a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel Align2 = AvailableAlloca->getAlignment(); 1965a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel // If we don't have data layout information, and only one alloca is using 1975a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel // the target default, then we can't safely merge them because we can't 1985a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel // pick the greater alignment. 1995a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel if (!TD && (!Align1 || !Align2) && Align1 != Align2) 2005a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel continue; 201199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 202199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // The available alloca has to be in the right function, not in some other 203199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // function in this SCC. 204199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner if (AvailableAlloca->getParent() != AI->getParent()) 205199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner continue; 206199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 207199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // If the inlined function already uses this alloca then we can't reuse 208199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // it. 209199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner if (!UsedAllocas.insert(AvailableAlloca)) 210199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner continue; 211199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 212199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Otherwise, we *can* reuse it, RAUW AI into AvailableAlloca and declare 213199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // success! 2147d32b8032d7ec2472b994aab2ac3459e8d47c496Chris Lattner DEBUG(dbgs() << " ***MERGED ALLOCA: " << *AI << "\n\t\tINTO: " 2157d32b8032d7ec2472b994aab2ac3459e8d47c496Chris Lattner << *AvailableAlloca << '\n'); 216199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 217199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner AI->replaceAllUsesWith(AvailableAlloca); 2185a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel 21986f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel if (Align1 != Align2) { 22086f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel if (!Align1 || !Align2) { 22186f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel assert(TD && "DataLayout required to compare default alignments"); 22286f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel unsigned TypeAlign = TD->getABITypeAlignment(AI->getAllocatedType()); 22386f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel 22486f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel Align1 = Align1 ? Align1 : TypeAlign; 22586f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel Align2 = Align2 ? Align2 : TypeAlign; 22686f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel } 22786f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel 22886f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel if (Align1 > Align2) 22986f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel AvailableAlloca->setAlignment(AI->getAlignment()); 23086f4f6526b18765cdb78bee593e1354bc9f55085Hal Finkel } 2315a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel 232199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner AI->eraseFromParent(); 233199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner MergedAwayAlloca = true; 234199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner ++NumMergedAllocas; 2357d32b8032d7ec2472b994aab2ac3459e8d47c496Chris Lattner IFI.StaticAllocas[AllocaNo] = 0; 236199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner break; 237199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner } 238fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 239199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // If we already nuked the alloca, we're done with it. 240199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner if (MergedAwayAlloca) 241199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner continue; 2427d32b8032d7ec2472b994aab2ac3459e8d47c496Chris Lattner 243199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // If we were unable to merge away the alloca either because there are no 244199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // allocas of the right type available or because we reused them all 245199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // already, remember that this alloca came from an inlined function and mark 246199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // it used so we don't reuse it for other allocas from this inline 247199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // operation. 248199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner AllocasForType.push_back(AI); 249199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner UsedAllocas.insert(AI); 250befa499d45ffcc32bd9902518aec18589464e47cChris Lattner } 251199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 252befa499d45ffcc32bd9902518aec18589464e47cChris Lattner return true; 253237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner} 254f8526cb711ec96cd2d5aff30da57f65ae8e5b7b8Jakob Stoklund Olesen 255570a4a5d9ca31f276a67502d1e0533d59d331feaJakob Stoklund Olesenunsigned Inliner::getInlineThreshold(CallSite CS) const { 256ab767213fdfc219384e26b8073783cb883974dcdPatrik Hägglund int thres = InlineThreshold; // -inline-threshold or else selected by 257ab767213fdfc219384e26b8073783cb883974dcdPatrik Hägglund // overall opt level 258570a4a5d9ca31f276a67502d1e0533d59d331feaJakob Stoklund Olesen 259ab767213fdfc219384e26b8073783cb883974dcdPatrik Hägglund // If -inline-threshold is not given, listen to the optsize attribute when it 260ab767213fdfc219384e26b8073783cb883974dcdPatrik Hägglund // would decrease the threshold. 261570a4a5d9ca31f276a67502d1e0533d59d331feaJakob Stoklund Olesen Function *Caller = CS.getCaller(); 262ab767213fdfc219384e26b8073783cb883974dcdPatrik Hägglund bool OptSize = Caller && !Caller->isDeclaration() && 263831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling Caller->getAttributes().hasAttribute(AttributeSet::FunctionIndex, 264831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling Attribute::OptimizeForSize); 265aa8405811ed9ad84e5afb70dac04ebfbae519316Nadav Rotem if (!(InlineLimit.getNumOccurrences() > 0) && OptSize && 266aa8405811ed9ad84e5afb70dac04ebfbae519316Nadav Rotem OptSizeThreshold < thres) 267f0907fe59093753fe5a9e8fe5adc399dbdc94627Jakob Stoklund Olesen thres = OptSizeThreshold; 268f0907fe59093753fe5a9e8fe5adc399dbdc94627Jakob Stoklund Olesen 269fcc934322bc6e0b89df8fbcdde59145f5af1179aQuentin Colombet // Listen to the inlinehint attribute when it would increase the threshold 270fcc934322bc6e0b89df8fbcdde59145f5af1179aQuentin Colombet // and the caller does not need to minimize its size. 271f0907fe59093753fe5a9e8fe5adc399dbdc94627Jakob Stoklund Olesen Function *Callee = CS.getCalledFunction(); 272ab767213fdfc219384e26b8073783cb883974dcdPatrik Hägglund bool InlineHint = Callee && !Callee->isDeclaration() && 273831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling Callee->getAttributes().hasAttribute(AttributeSet::FunctionIndex, 274831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling Attribute::InlineHint); 275fcc934322bc6e0b89df8fbcdde59145f5af1179aQuentin Colombet if (InlineHint && HintThreshold > thres 276831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling && !Caller->getAttributes().hasAttribute(AttributeSet::FunctionIndex, 277831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling Attribute::MinSize)) 278f0907fe59093753fe5a9e8fe5adc399dbdc94627Jakob Stoklund Olesen thres = HintThreshold; 279570a4a5d9ca31f276a67502d1e0533d59d331feaJakob Stoklund Olesen 280f0907fe59093753fe5a9e8fe5adc399dbdc94627Jakob Stoklund Olesen return thres; 281f8526cb711ec96cd2d5aff30da57f65ae8e5b7b8Jakob Stoklund Olesen} 282f8526cb711ec96cd2d5aff30da57f65ae8e5b7b8Jakob Stoklund Olesen 2831a99dbfe3b70c83d3f3e4648b5868c04697cd77cDaniel Dunbar/// shouldInline - Return true if the inliner should attempt to inline 2841a99dbfe3b70c83d3f3e4648b5868c04697cd77cDaniel Dunbar/// at the given CallSite. 2851a99dbfe3b70c83d3f3e4648b5868c04697cd77cDaniel Dunbarbool Inliner::shouldInline(CallSite CS) { 286c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar InlineCost IC = getInlineCost(CS); 2871a99dbfe3b70c83d3f3e4648b5868c04697cd77cDaniel Dunbar 288c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar if (IC.isAlways()) { 289c0aa67950ae0f6e9611240d8f0e3ac49dc8195c0David Greene DEBUG(dbgs() << " Inlining: cost=always" 29084a832f9272ed7f1a47c3e019c770b62e373cc6cBill Wendling << ", Call: " << *CS.getInstruction() << "\n"); 291c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar return true; 292c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar } 293c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar 294c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar if (IC.isNever()) { 295c0aa67950ae0f6e9611240d8f0e3ac49dc8195c0David Greene DEBUG(dbgs() << " NOT Inlining: cost=never" 29684a832f9272ed7f1a47c3e019c770b62e373cc6cBill Wendling << ", Call: " << *CS.getInstruction() << "\n"); 297c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar return false; 298c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar } 299c5e1ec47c719806fcc882470595960512edc7441Daniel Dunbar 300e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen Function *Caller = CS.getCaller(); 301f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth if (!IC) { 302f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth DEBUG(dbgs() << " NOT Inlining: cost=" << IC.getCost() 303f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth << ", thres=" << (IC.getCostDelta() + IC.getCost()) 30484a832f9272ed7f1a47c3e019c770b62e373cc6cBill Wendling << ", Call: " << *CS.getInstruction() << "\n"); 3051a99dbfe3b70c83d3f3e4648b5868c04697cd77cDaniel Dunbar return false; 3061a99dbfe3b70c83d3f3e4648b5868c04697cd77cDaniel Dunbar } 307135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 308b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // Try to detect the case where the current inlining candidate caller (call 309b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // it B) is a static or linkonce-ODR function and is an inlining candidate 310b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // elsewhere, and the current candidate callee (call it C) is large enough 311b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // that inlining it into B would make B too big to inline later. In these 312b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // circumstances it may be best not to inline C into B, but to inline B into 313b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // its callers. 314b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // 315b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // This only applies to static and linkonce-ODR functions because those are 316b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // expected to be available for inlining in the translation units where they 317b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // are used. Thus we will always have the opportunity to make local inlining 318b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // decisions. Importantly the linkonce-ODR linkage covers inline functions 319b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth // and templates in C++. 320f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth // 321f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth // FIXME: All of this logic should be sunk into getInlineCost. It relies on 322f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth // the internal implementation of the inline cost metrics rather than 323f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth // treating them as truly abstract units etc. 324b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth if (Caller->hasLocalLinkage() || 325b16117c368ad4e6d004ac912549b2c6ed06731a5Chandler Carruth Caller->getLinkage() == GlobalValue::LinkOnceODRLinkage) { 326e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen int TotalSecondaryCost = 0; 327f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth // The candidate cost to be imposed upon the current function. 328f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth int CandidateCost = IC.getCost() - (InlineConstants::CallPenalty + 1); 329c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen // This bool tracks what happens if we do NOT inline C into B. 330dacffb6679ff99fec4cc9c54f4257d2913870d01Chandler Carruth bool callerWillBeRemoved = Caller->hasLocalLinkage(); 331c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen // This bool tracks what happens if we DO inline C into B. 332c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen bool inliningPreventsSomeOuterInline = false; 333e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen for (Value::use_iterator I = Caller->use_begin(), E =Caller->use_end(); 334e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen I != E; ++I) { 3357d3056b16038a6a09c452c0dfcc3c8f4e421506aGabor Greif CallSite CS2(*I); 336e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen 337e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen // If this isn't a call to Caller (it could be some other sort 338c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen // of reference) skip it. Such references will prevent the caller 339c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen // from being removed. 340c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen if (!CS2 || CS2.getCalledFunction() != Caller) { 341c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen callerWillBeRemoved = false; 342e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen continue; 343c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen } 344e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen 345e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen InlineCost IC2 = getInlineCost(CS2); 346d6fc26217e194372cabe4ef9e2514beac511a943Chandler Carruth ++NumCallerCallersAnalyzed; 347f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth if (!IC2) { 348c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen callerWillBeRemoved = false; 349f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth continue; 350f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth } 351f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth if (IC2.isAlways()) 352e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen continue; 353e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen 354f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth // See if inlining or original callsite would erase the cost delta of 355f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth // this callsite. We subtract off the penalty for the call instruction, 356f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth // which we would be deleting. 357f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth if (IC2.getCostDelta() <= CandidateCost) { 358c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen inliningPreventsSomeOuterInline = true; 359f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth TotalSecondaryCost += IC2.getCost(); 360e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen } 361e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen } 362e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen // If all outer calls to Caller would get inlined, the cost for the last 363e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen // one is set very low by getInlineCost, in anticipation that Caller will 364e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen // be removed entirely. We did not account for this above unless there 365e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen // is only one caller of Caller. 366c84e3c0c03a0dab7aea7047e7b8e38051542f7e4Dale Johannesen if (callerWillBeRemoved && Caller->use_begin() != Caller->use_end()) 367bdb984bc2757114bc706026603ed40d7f508c4c1Dale Johannesen TotalSecondaryCost += InlineConstants::LastCallToStaticBonus; 368e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen 369f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth if (inliningPreventsSomeOuterInline && TotalSecondaryCost < IC.getCost()) { 370f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth DEBUG(dbgs() << " NOT Inlining: " << *CS.getInstruction() << 371f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth " Cost = " << IC.getCost() << 372e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen ", outer Cost = " << TotalSecondaryCost << '\n'); 373e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen return false; 374e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen } 375e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen } 376e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen 377f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth DEBUG(dbgs() << " Inlining: cost=" << IC.getCost() 378f2286b0152f0b942e82d8e809186e5cc0d247131Chandler Carruth << ", thres=" << (IC.getCostDelta() + IC.getCost()) 379e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen << ", Call: " << *CS.getInstruction() << '\n'); 380135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner return true; 3811a99dbfe3b70c83d3f3e4648b5868c04697cd77cDaniel Dunbar} 382237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner 383159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner/// InlineHistoryIncludes - Return true if the specified inline history ID 384159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner/// indicates an inline history that includes the specified function. 385159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattnerstatic bool InlineHistoryIncludes(Function *F, int InlineHistoryID, 386159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner const SmallVectorImpl<std::pair<Function*, int> > &InlineHistory) { 387159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner while (InlineHistoryID != -1) { 388159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner assert(unsigned(InlineHistoryID) < InlineHistory.size() && 389159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner "Invalid inline history ID"); 390159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner if (InlineHistory[InlineHistoryID].first == F) 391159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner return true; 392159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner InlineHistoryID = InlineHistory[InlineHistoryID].second; 393159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner } 394159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner return false; 395159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner} 396159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner 3972decb22222cac46bb1d9163e7b89d7e5be8ef65fChris Lattnerbool Inliner::runOnSCC(CallGraphSCC &SCC) { 398237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner CallGraph &CG = getAnalysis<CallGraph>(); 3993574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD = getAnalysisIfAvailable<DataLayout>(); 4008e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer const TargetLibraryInfo *TLI = getAnalysisIfAvailable<TargetLibraryInfo>(); 401237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner 40216581bf931c0ccf2f8993397acfa4e1d509a68dcDale Johannesen SmallPtrSet<Function*, 8> SCCFunctions; 403c0aa67950ae0f6e9611240d8f0e3ac49dc8195c0David Greene DEBUG(dbgs() << "Inliner visiting SCC:"); 4042decb22222cac46bb1d9163e7b89d7e5be8ef65fChris Lattner for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { 4052decb22222cac46bb1d9163e7b89d7e5be8ef65fChris Lattner Function *F = (*I)->getFunction(); 406befa499d45ffcc32bd9902518aec18589464e47cChris Lattner if (F) SCCFunctions.insert(F); 407c0aa67950ae0f6e9611240d8f0e3ac49dc8195c0David Greene DEBUG(dbgs() << " " << (F ? F->getName() : "INDIRECTNODE")); 408237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner } 409237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner 410befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // Scan through and identify all call sites ahead of time so that we only 411befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // inline call sites in the original functions, not call sites that result 412befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // from inlining other functions. 413159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner SmallVector<std::pair<CallSite, int>, 16> CallSites; 414159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner 415159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // When inlining a callee produces new call sites, we want to keep track of 416159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // the fact that they were inlined from the callee. This allows us to avoid 417159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // infinite inlining in some obscure cases. To represent this, we use an 418159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // index into the InlineHistory vector. 419159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner SmallVector<std::pair<Function*, int>, 8> InlineHistory; 420befa499d45ffcc32bd9902518aec18589464e47cChris Lattner 4212decb22222cac46bb1d9163e7b89d7e5be8ef65fChris Lattner for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { 4222decb22222cac46bb1d9163e7b89d7e5be8ef65fChris Lattner Function *F = (*I)->getFunction(); 423135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (!F) continue; 424135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 425135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) 426135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) { 4277d3056b16038a6a09c452c0dfcc3c8f4e421506aGabor Greif CallSite CS(cast<Value>(I)); 428e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen // If this isn't a call, or it is a call to an intrinsic, it can 429d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner // never be inlined. 4307d3056b16038a6a09c452c0dfcc3c8f4e421506aGabor Greif if (!CS || isa<IntrinsicInst>(I)) 431135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 432135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 433d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner // If this is a direct call to an external function, we can never inline 434d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner // it. If it is an indirect call, inlining may resolve it to be a 435d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner // direct call, so we keep it. 436d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner if (CS.getCalledFunction() && CS.getCalledFunction()->isDeclaration()) 437d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner continue; 438d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner 439159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner CallSites.push_back(std::make_pair(CS, -1)); 440135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 441135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 442237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner 443c0aa67950ae0f6e9611240d8f0e3ac49dc8195c0David Greene DEBUG(dbgs() << ": " << CallSites.size() << " call sites.\n"); 444fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 4454471136e4db67f5b6cf064cb3b0a7668f15bfe6cChris Lattner // If there are no calls in this function, exit early. 4464471136e4db67f5b6cf064cb3b0a7668f15bfe6cChris Lattner if (CallSites.empty()) 4474471136e4db67f5b6cf064cb3b0a7668f15bfe6cChris Lattner return false; 4484471136e4db67f5b6cf064cb3b0a7668f15bfe6cChris Lattner 449befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // Now that we have all of the call sites, move the ones to functions in the 450befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // current SCC to the end of the list. 451befa499d45ffcc32bd9902518aec18589464e47cChris Lattner unsigned FirstCallInSCC = CallSites.size(); 452befa499d45ffcc32bd9902518aec18589464e47cChris Lattner for (unsigned i = 0; i < FirstCallInSCC; ++i) 453159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner if (Function *F = CallSites[i].first.getCalledFunction()) 454befa499d45ffcc32bd9902518aec18589464e47cChris Lattner if (SCCFunctions.count(F)) 455befa499d45ffcc32bd9902518aec18589464e47cChris Lattner std::swap(CallSites[i--], CallSites[--FirstCallInSCC]); 456fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 457199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 458199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner InlinedArrayAllocasTy InlinedArrayAllocas; 45960915146f4d35e12f10dcdaa155596fac79184daChris Lattner InlineFunctionInfo InlineInfo(&CG, TD); 460199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 461befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // Now that we have all of the call sites, loop over them and inline them if 462befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // it looks profitable to do so. 463befa499d45ffcc32bd9902518aec18589464e47cChris Lattner bool Changed = false; 464befa499d45ffcc32bd9902518aec18589464e47cChris Lattner bool LocalChange; 465befa499d45ffcc32bd9902518aec18589464e47cChris Lattner do { 466befa499d45ffcc32bd9902518aec18589464e47cChris Lattner LocalChange = false; 467befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // Iterate over the outer loop because inlining functions can cause indirect 468befa499d45ffcc32bd9902518aec18589464e47cChris Lattner // calls to become direct calls. 469135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (unsigned CSi = 0; CSi != CallSites.size(); ++CSi) { 470159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner CallSite CS = CallSites[CSi].first; 471199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 472dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner Function *Caller = CS.getCaller(); 473199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner Function *Callee = CS.getCalledFunction(); 474dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner 475dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // If this call site is dead and it is to a readonly function, we should 476dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // just delete the call instead of trying to inline it, regardless of 477dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // size. This happens because IPSCCP propagates the result out of the 478dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // call and then we're left with the dead call. 4798e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer if (isInstructionTriviallyDead(CS.getInstruction(), TLI)) { 480c0aa67950ae0f6e9611240d8f0e3ac49dc8195c0David Greene DEBUG(dbgs() << " -> Deleting dead call: " 481dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner << *CS.getInstruction() << "\n"); 482dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // Update the call graph by deleting the edge from Callee to Caller. 483dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner CG[Caller]->removeCallEdgeFor(CS); 484dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner CS.getInstruction()->eraseFromParent(); 485dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner ++NumCallsDeleted; 486dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner } else { 487dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // We can only inline direct calls to non-declarations. 488dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner if (Callee == 0 || Callee->isDeclaration()) continue; 489135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 490f0193ed8decb2e78d8d5ec4a4eaeed8f3036bf6eEric Christopher // If this call site was obtained by inlining another function, verify 491159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // that the include path for the function did not include the callee 4927d32b8032d7ec2472b994aab2ac3459e8d47c496Chris Lattner // itself. If so, we'd be recursively inlining the same function, 493159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // which would provide the same callsites, which would cause us to 494159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // infinitely inline. 495159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner int InlineHistoryID = CallSites[CSi].second; 496159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner if (InlineHistoryID != -1 && 497159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner InlineHistoryIncludes(Callee, InlineHistoryID, InlineHistory)) 498159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner continue; 499159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner 500159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner 501dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // If the policy determines that we should inline this function, 502dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // try to do so. 503dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner if (!shouldInline(CS)) 504dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner continue; 505e91b9a3b59688023e20cee8441179300b87c844eDale Johannesen 506fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner // Attempt to inline the function. 5076c3ee0f3c9684e588c8852d90c891d6354175c9eChris Lattner if (!InlineCallIfPossible(CS, InlineInfo, InlinedArrayAllocas, 5085a5ebb7f9fa7fa82c0c466a36a90e5c18bb13073Hal Finkel InlineHistoryID, InsertLifetime, TD)) 509dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner continue; 510dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner ++NumInlined; 511159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner 5120ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner // If inlining this function gave us any new call sites, throw them 513fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner // onto our worklist to process. They are useful inline candidates. 5140ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner if (!InlineInfo.InlinedCalls.empty()) { 515159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // Create a new inline history entry for this, so that we remember 516159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner // that these new callsites came about due to inlining Callee. 517159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner int NewHistoryID = InlineHistory.size(); 518159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner InlineHistory.push_back(std::make_pair(Callee, InlineHistoryID)); 519159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner 5200ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner for (unsigned i = 0, e = InlineInfo.InlinedCalls.size(); 521159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner i != e; ++i) { 5220ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner Value *Ptr = InlineInfo.InlinedCalls[i]; 523d54f9a4c3bcdb247ea4aa311251c19242b03be63Chandler Carruth CallSites.push_back(std::make_pair(CallSite(Ptr), NewHistoryID)); 524159528702aed7222cb30c3e8b55287e4ca8068cfChris Lattner } 525076863225ce070345ff7048f48b3550e00598a10Chris Lattner } 526dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner } 527135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 528dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // If we inlined or deleted the last possible call site to the function, 529dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner // delete the function body now. 530dbab4dc942e0c3286415908762de71a9447f9dfaChris Lattner if (Callee && Callee->use_empty() && Callee->hasLocalLinkage() && 531d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner // TODO: Can remove if in SCC now. 532b374b90e81d0ce6b5d02041ba4f7b15a945b38d8Chris Lattner !SCCFunctions.count(Callee) && 533d43d5e832f756c9d2c0c8ff4d2f51807a27cab8dChris Lattner 534b374b90e81d0ce6b5d02041ba4f7b15a945b38d8Chris Lattner // The function may be apparently dead, but if there are indirect 535b374b90e81d0ce6b5d02041ba4f7b15a945b38d8Chris Lattner // callgraph references to the node, we cannot delete it yet, this 536b374b90e81d0ce6b5d02041ba4f7b15a945b38d8Chris Lattner // could invalidate the CGSCC iterator. 537b374b90e81d0ce6b5d02041ba4f7b15a945b38d8Chris Lattner CG[Callee]->getNumReferences() == 0) { 538c0aa67950ae0f6e9611240d8f0e3ac49dc8195c0David Greene DEBUG(dbgs() << " -> Deleting dead function: " 539199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner << Callee->getName() << "\n"); 540199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner CallGraphNode *CalleeNode = CG[Callee]; 541199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 542199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Remove any call graph edges from the callee to its callees. 543199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner CalleeNode->removeAllCalledFunctions(); 544199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner 545199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner // Removing the node for callee from the call graph and delete it. 546199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner delete CG.removeFunctionFromModule(CalleeNode); 547199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner ++NumDeleted; 548199ba42cbf56b2fc9c708edb4f08f97dd99ddd49Chris Lattner } 549135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 550135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Remove this call site from the list. If possible, use 551135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // swap/pop_back for efficiency, but do not use it if doing so would 552135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // move a call site to a function in this SCC before the 553135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // 'FirstCallInSCC' barrier. 5542decb22222cac46bb1d9163e7b89d7e5be8ef65fChris Lattner if (SCC.isSingular()) { 555c29df3cac735bc85d16e4ef3186cb50e41bec7bbBenjamin Kramer CallSites[CSi] = CallSites.back(); 556135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CallSites.pop_back(); 557135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } else { 558135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CallSites.erase(CallSites.begin()+CSi); 559237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner } 560135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner --CSi; 561135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 562135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner Changed = true; 563135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner LocalChange = true; 564135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 565befa499d45ffcc32bd9902518aec18589464e47cChris Lattner } while (LocalChange); 566237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner 567775cbdd51a3b33dd5eb343689f65ab5cc8ac7118Chris Lattner return Changed; 568237ef567f6764f24a47c63121cc0a599ddc8f56dChris Lattner} 569d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 57068d57e7ae80044401efd889270a12c71b3efb9abChris Lattner// doFinalization - Remove now-dead linkonce functions at the end of 57168d57e7ae80044401efd889270a12c71b3efb9abChris Lattner// processing to avoid breaking the SCC traversal. 57268d57e7ae80044401efd889270a12c71b3efb9abChris Lattnerbool Inliner::doFinalization(CallGraph &CG) { 573b7c6bf1e073088635951435acedff793add1cefdDevang Patel return removeDeadFunctions(CG); 574b7c6bf1e073088635951435acedff793add1cefdDevang Patel} 575b7c6bf1e073088635951435acedff793add1cefdDevang Patel 576135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// removeDeadFunctions - Remove dead functions that are not included in 577135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// DNR (Do Not Remove) list. 578f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruthbool Inliner::removeDeadFunctions(CallGraph &CG, bool AlwaysInlineOnly) { 579f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth SmallVector<CallGraphNode*, 16> FunctionsToRemove; 5803e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner 5813e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner // Scan for all of the functions, looking for ones that should now be removed 5823e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner // from the program. Insert the dead ones in the FunctionsToRemove set. 5833e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner for (CallGraph::iterator I = CG.begin(), E = CG.end(); I != E; ++I) { 5843e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner CallGraphNode *CGN = I->second; 585135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner Function *F = CGN->getFunction(); 586f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth if (!F || F->isDeclaration()) 587f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth continue; 588f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth 589f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth // Handle the case when this function is called and we only want to care 590f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth // about always-inline functions. This is a bit of a hack to share code 591f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth // between here and the InlineAlways pass. 5926765834754cbb3cb0f15b4b15e98c5e73fa50066Bill Wendling if (AlwaysInlineOnly && 593831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling !F->getAttributes().hasAttribute(AttributeSet::FunctionIndex, 594831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling Attribute::AlwaysInline)) 595f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth continue; 596f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth 597135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // If the only remaining users of the function are dead constants, remove 598135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // them. 599135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner F->removeDeadConstantUsers(); 600135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 601c66330504c3f433430a28cd7f7f981e555c51bceEli Friedman if (!F->isDefTriviallyDead()) 602135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 603135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 604135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Remove any call graph edges from the function to its callees. 605135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CGN->removeAllCalledFunctions(); 606135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 607135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Remove any edges from the external node to the function's call graph 608135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // node. These edges might have been made irrelegant due to 609135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // optimization of the program. 610135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CG.getExternalCallingNode()->removeAnyCallEdgeTo(CGN); 611fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 612135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Removing the node for callee from the call graph and delete it. 613f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth FunctionsToRemove.push_back(CGN); 61468d57e7ae80044401efd889270a12c71b3efb9abChris Lattner } 615f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth if (FunctionsToRemove.empty()) 616f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth return false; 6173e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner 6183e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner // Now that we know which functions to delete, do so. We didn't want to do 6193e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner // this inline, because that would invalidate our CallGraph::iterator 6203e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner // objects. :( 621135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // 622f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth // Note that it doesn't matter that we are iterating over a non-stable order 623135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // here to do this, it doesn't matter which order the functions are deleted 624135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // in. 625dafe48e230916ce0de4228d81dece732159994f1Chandler Carruth array_pod_sort(FunctionsToRemove.begin(), FunctionsToRemove.end()); 626f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth FunctionsToRemove.erase(std::unique(FunctionsToRemove.begin(), 627f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth FunctionsToRemove.end()), 628f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth FunctionsToRemove.end()); 629f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth for (SmallVectorImpl<CallGraphNode *>::iterator I = FunctionsToRemove.begin(), 630f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth E = FunctionsToRemove.end(); 631f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth I != E; ++I) { 6323e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner delete CG.removeFunctionFromModule(*I); 6333e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner ++NumDeleted; 6343e1358a9fa1ebd3f51c94eb69da55d693895fe7cChris Lattner } 635f91f5af802bd4487c49ee17cd0d3e46c6456263eChandler Carruth return true; 63668d57e7ae80044401efd889270a12c71b3efb9abChris Lattner} 637