[llvm] r297081 - [Outliner] Fixed Asan bot failure in r296418
Jessica Paquette via llvm-commits
llvm-commits at lists.llvm.org
Mon Mar 6 13:31:18 PST 2017
Author: paquette
Date: Mon Mar 6 15:31:18 2017
New Revision: 297081
URL: http://llvm.org/viewvc/llvm-project?rev=297081&view=rev
Log:
[Outliner] Fixed Asan bot failure in r296418
Fixed the asan bot failure which led to the last commit of the outliner being reverted.
The change is in lib/CodeGen/MachineOutliner.cpp in the SuffixTree's constructor. LeafVector
is no longer initialized using reserve but just a standard constructor.
Added:
llvm/trunk/lib/CodeGen/MachineOutliner.cpp
llvm/trunk/test/CodeGen/X86/machine-outliner-debuginfo.ll
llvm/trunk/test/CodeGen/X86/machine-outliner.ll
Modified:
llvm/trunk/include/llvm/CodeGen/Passes.h
llvm/trunk/include/llvm/InitializePasses.h
llvm/trunk/include/llvm/Target/TargetInstrInfo.h
llvm/trunk/lib/CodeGen/CMakeLists.txt
llvm/trunk/lib/CodeGen/CodeGen.cpp
llvm/trunk/lib/CodeGen/TargetPassConfig.cpp
llvm/trunk/lib/Target/X86/X86InstrInfo.cpp
llvm/trunk/lib/Target/X86/X86InstrInfo.h
Modified: llvm/trunk/include/llvm/CodeGen/Passes.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/Passes.h?rev=297081&r1=297080&r2=297081&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/Passes.h (original)
+++ llvm/trunk/include/llvm/CodeGen/Passes.h Mon Mar 6 15:31:18 2017
@@ -405,6 +405,11 @@ namespace llvm {
/// This pass combine basic blocks guarded by the same branch.
extern char &BranchCoalescingID;
+
+ /// This pass performs outlining on machine instructions directly before
+ /// printing assembly.
+ ModulePass *createMachineOutlinerPass();
+
} // End llvm namespace
/// Target machine pass initializer for passes with dependencies. Use with
Modified: llvm/trunk/include/llvm/InitializePasses.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/InitializePasses.h?rev=297081&r1=297080&r2=297081&view=diff
==============================================================================
--- llvm/trunk/include/llvm/InitializePasses.h (original)
+++ llvm/trunk/include/llvm/InitializePasses.h Mon Mar 6 15:31:18 2017
@@ -237,6 +237,7 @@ void initializeMachineLICMPass(PassRegis
void initializeMachineLoopInfoPass(PassRegistry&);
void initializeMachineModuleInfoPass(PassRegistry&);
void initializeMachineOptimizationRemarkEmitterPassPass(PassRegistry&);
+void initializeMachineOutlinerPass(PassRegistry&);
void initializeMachinePipelinerPass(PassRegistry&);
void initializeMachinePostDominatorTreePass(PassRegistry&);
void initializeMachineRegionInfoPassPass(PassRegistry&);
Modified: llvm/trunk/include/llvm/Target/TargetInstrInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetInstrInfo.h?rev=297081&r1=297080&r2=297081&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Target/TargetInstrInfo.h (original)
+++ llvm/trunk/include/llvm/Target/TargetInstrInfo.h Mon Mar 6 15:31:18 2017
@@ -1508,6 +1508,63 @@ public:
return false;
}
+ /// \brief Return how many instructions would be saved by outlining a
+ /// sequence containing \p SequenceSize instructions that appears
+ /// \p Occurrences times in a module.
+ virtual unsigned getOutliningBenefit(size_t SequenceSize, size_t Occurrences)
+ const {
+ llvm_unreachable(
+ "Target didn't implement TargetInstrInfo::getOutliningBenefit!");
+ }
+
+ /// Represents how an instruction should be mapped by the outliner.
+ /// \p Legal instructions are those which are safe to outline.
+ /// \p Illegal instructions are those which cannot be outlined.
+ /// \p Invisible instructions are instructions which can be outlined, but
+ /// shouldn't actually impact the outlining result.
+ enum MachineOutlinerInstrType {Legal, Illegal, Invisible};
+
+ /// Return true if the instruction is legal to outline.
+ virtual MachineOutlinerInstrType getOutliningType(MachineInstr &MI) const {
+ llvm_unreachable(
+ "Target didn't implement TargetInstrInfo::getOutliningType!");
+ }
+
+ /// Insert a custom epilogue for outlined functions.
+ /// This may be empty, in which case no epilogue or return statement will be
+ /// emitted.
+ virtual void insertOutlinerEpilogue(MachineBasicBlock &MBB,
+ MachineFunction &MF) const {
+ llvm_unreachable(
+ "Target didn't implement TargetInstrInfo::insertOutlinerEpilogue!");
+ }
+
+ /// Insert a call to an outlined function into the program.
+ /// Returns an iterator to the spot where we inserted the call. This must be
+ /// implemented by the target.
+ virtual MachineBasicBlock::iterator
+ insertOutlinedCall(Module &M, MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &It, MachineFunction &MF)
+ const {
+ llvm_unreachable(
+ "Target didn't implement TargetInstrInfo::insertOutlinedCall!");
+ }
+
+ /// Insert a custom prologue for outlined functions.
+ /// This may be empty, in which case no prologue will be emitted.
+ virtual void insertOutlinerPrologue(MachineBasicBlock &MBB,
+ MachineFunction &MF) const {
+ llvm_unreachable(
+ "Target didn't implement TargetInstrInfo::insertOutlinerPrologue!");
+ }
+
+ /// Return true if the function can safely be outlined from.
+ /// By default, this means that the function has no red zone.
+ virtual bool isFunctionSafeToOutlineFrom(MachineFunction &F) const {
+ llvm_unreachable("Target didn't implement "
+ "TargetInstrInfo::isFunctionSafeToOutlineFrom!");
+ }
+
private:
unsigned CallFrameSetupOpcode, CallFrameDestroyOpcode;
unsigned CatchRetOpcode;
Modified: llvm/trunk/lib/CodeGen/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/CMakeLists.txt?rev=297081&r1=297080&r2=297081&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/CMakeLists.txt (original)
+++ llvm/trunk/lib/CodeGen/CMakeLists.txt Mon Mar 6 15:31:18 2017
@@ -75,6 +75,7 @@ add_llvm_library(LLVMCodeGen
MachineModuleInfo.cpp
MachineModuleInfoImpls.cpp
MachineOptimizationRemarkEmitter.cpp
+ MachineOutliner.cpp
MachinePassRegistry.cpp
MachinePipeliner.cpp
MachinePostDominators.cpp
Modified: llvm/trunk/lib/CodeGen/CodeGen.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/CodeGen.cpp?rev=297081&r1=297080&r2=297081&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/CodeGen.cpp (original)
+++ llvm/trunk/lib/CodeGen/CodeGen.cpp Mon Mar 6 15:31:18 2017
@@ -58,6 +58,7 @@ void llvm::initializeCodeGen(PassRegistr
initializeMachineLoopInfoPass(Registry);
initializeMachineModuleInfoPass(Registry);
initializeMachineOptimizationRemarkEmitterPassPass(Registry);
+ initializeMachineOutlinerPass(Registry);
initializeMachinePipelinerPass(Registry);
initializeMachinePostDominatorTreePass(Registry);
initializeMachineRegionInfoPassPass(Registry);
Added: llvm/trunk/lib/CodeGen/MachineOutliner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/MachineOutliner.cpp?rev=297081&view=auto
==============================================================================
--- llvm/trunk/lib/CodeGen/MachineOutliner.cpp (added)
+++ llvm/trunk/lib/CodeGen/MachineOutliner.cpp Mon Mar 6 15:31:18 2017
@@ -0,0 +1,1399 @@
+//===---- MachineOutliner.cpp - Outline instructions -----------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Replaces repeated sequences of instructions with function calls.
+///
+/// This works by placing every instruction from every basic block in a
+/// suffix tree, and repeatedly querying that tree for repeated sequences of
+/// instructions. If a sequence of instructions appears often, then it ought
+/// to be beneficial to pull out into a function.
+///
+/// This was originally presented at the 2016 LLVM Developers' Meeting in the
+/// talk "Reducing Code Size Using Outlining". For a high-level overview of
+/// how this pass works, the talk is available on YouTube at
+///
+/// https://www.youtube.com/watch?v=yorld-WSOeU
+///
+/// The slides for the talk are available at
+///
+/// http://www.llvm.org/devmtg/2016-11/Slides/Paquette-Outliner.pdf
+///
+/// The talk provides an overview of how the outliner finds candidates and
+/// ultimately outlines them. It describes how the main data structure for this
+/// pass, the suffix tree, is queried and purged for candidates. It also gives
+/// a simplified suffix tree construction algorithm for suffix trees based off
+/// of the algorithm actually used here, Ukkonen's algorithm.
+///
+/// For the original RFC for this pass, please see
+///
+/// http://lists.llvm.org/pipermail/llvm-dev/2016-August/104170.html
+///
+/// For more information on the suffix tree data structure, please see
+/// https://www.cs.helsinki.fi/u/ukkonen/SuffixT1withFigs.pdf
+///
+//===----------------------------------------------------------------------===//
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
+#include <functional>
+#include <map>
+#include <sstream>
+#include <tuple>
+#include <vector>
+
+#define DEBUG_TYPE "machine-outliner"
+
+using namespace llvm;
+
+STATISTIC(NumOutlined, "Number of candidates outlined");
+STATISTIC(FunctionsCreated, "Number of functions created");
+
+namespace {
+
+/// Represents an undefined index in the suffix tree.
+const size_t EmptyIdx = -1;
+
+/// A node in a suffix tree which represents a substring or suffix.
+///
+/// Each node has either no children or at least two children, with the root
+/// being a exception in the empty tree.
+///
+/// Children are represented as a map between unsigned integers and nodes. If
+/// a node N has a child M on unsigned integer k, then the mapping represented
+/// by N is a proper prefix of the mapping represented by M. Note that this,
+/// although similar to a trie is somewhat different: each node stores a full
+/// substring of the full mapping rather than a single character state.
+///
+/// Each internal node contains a pointer to the internal node representing
+/// the same string, but with the first character chopped off. This is stored
+/// in \p Link. Each leaf node stores the start index of its respective
+/// suffix in \p SuffixIdx.
+struct SuffixTreeNode {
+
+ /// The children of this node.
+ ///
+ /// A child existing on an unsigned integer implies that from the mapping
+ /// represented by the current node, there is a way to reach another
+ /// mapping by tacking that character on the end of the current string.
+ DenseMap<unsigned, SuffixTreeNode *> Children;
+
+ /// A flag set to false if the node has been pruned from the tree.
+ bool IsInTree = true;
+
+ /// The start index of this node's substring in the main string.
+ size_t StartIdx = EmptyIdx;
+
+ /// The end index of this node's substring in the main string.
+ ///
+ /// Every leaf node must have its \p EndIdx incremented at the end of every
+ /// step in the construction algorithm. To avoid having to update O(N)
+ /// nodes individually at the end of every step, the end index is stored
+ /// as a pointer.
+ size_t *EndIdx = nullptr;
+
+ /// For leaves, the start index of the suffix represented by this node.
+ ///
+ /// For all other nodes, this is ignored.
+ size_t SuffixIdx = EmptyIdx;
+
+ /// \brief For internal nodes, a pointer to the internal node representing
+ /// the same sequence with the first character chopped off.
+ ///
+ /// This has two major purposes in the suffix tree. The first is as a
+ /// shortcut in Ukkonen's construction algorithm. One of the things that
+ /// Ukkonen's algorithm does to achieve linear-time construction is
+ /// keep track of which node the next insert should be at. This makes each
+ /// insert O(1), and there are a total of O(N) inserts. The suffix link
+ /// helps with inserting children of internal nodes.
+ ///
+ /// Say we add a child to an internal node with associated mapping S. The
+ /// next insertion must be at the node representing S - its first character.
+ /// This is given by the way that we iteratively build the tree in Ukkonen's
+ /// algorithm. The main idea is to look at the suffixes of each prefix in the
+ /// string, starting with the longest suffix of the prefix, and ending with
+ /// the shortest. Therefore, if we keep pointers between such nodes, we can
+ /// move to the next insertion point in O(1) time. If we don't, then we'd
+ /// have to query from the root, which takes O(N) time. This would make the
+ /// construction algorithm O(N^2) rather than O(N).
+ ///
+ /// The suffix link is also used during the tree pruning process to let us
+ /// quickly throw out a bunch of potential overlaps. Say we have a sequence
+ /// S we want to outline. Then each of its suffixes contribute to at least
+ /// one overlapping case. Therefore, we can follow the suffix links
+ /// starting at the node associated with S to the root and "delete" those
+ /// nodes, save for the root. For each candidate, this removes
+ /// O(|candidate|) overlaps from the search space. We don't actually
+ /// completely invalidate these nodes though; doing that is far too
+ /// aggressive. Consider the following pathological string:
+ ///
+ /// 1 2 3 1 2 3 2 3 2 3 2 3 2 3 2 3 2 3
+ ///
+ /// If we, for the sake of example, outlined 1 2 3, then we would throw
+ /// out all instances of 2 3. This isn't desirable. To get around this,
+ /// when we visit a link node, we decrement its occurrence count by the
+ /// number of sequences we outlined in the current step. In the pathological
+ /// example, the 2 3 node would have an occurrence count of 8, while the
+ /// 1 2 3 node would have an occurrence count of 2. Thus, the 2 3 node
+ /// would survive to the next round allowing us to outline the extra
+ /// instances of 2 3.
+ SuffixTreeNode *Link = nullptr;
+
+ /// The parent of this node. Every node except for the root has a parent.
+ SuffixTreeNode *Parent = nullptr;
+
+ /// The number of times this node's string appears in the tree.
+ ///
+ /// This is equal to the number of leaf children of the string. It represents
+ /// the number of suffixes that the node's string is a prefix of.
+ size_t OccurrenceCount = 0;
+
+ /// Returns true if this node is a leaf.
+ bool isLeaf() const { return SuffixIdx != EmptyIdx; }
+
+ /// Returns true if this node is the root of its owning \p SuffixTree.
+ bool isRoot() const { return StartIdx == EmptyIdx; }
+
+ /// Return the number of elements in the substring associated with this node.
+ size_t size() const {
+
+ // Is it the root? If so, it's the empty string so return 0.
+ if (isRoot())
+ return 0;
+
+ assert(*EndIdx != EmptyIdx && "EndIdx is undefined!");
+
+ // Size = the number of elements in the string.
+ // For example, [0 1 2 3] has length 4, not 3. 3-0 = 3, so we have 3-0+1.
+ return *EndIdx - StartIdx + 1;
+ }
+
+ SuffixTreeNode(size_t StartIdx, size_t *EndIdx, SuffixTreeNode *Link,
+ SuffixTreeNode *Parent)
+ : StartIdx(StartIdx), EndIdx(EndIdx), Link(Link), Parent(Parent) {}
+
+ SuffixTreeNode() {}
+};
+
+/// A data structure for fast substring queries.
+///
+/// Suffix trees represent the suffixes of their input strings in their leaves.
+/// A suffix tree is a type of compressed trie structure where each node
+/// represents an entire substring rather than a single character. Each leaf
+/// of the tree is a suffix.
+///
+/// A suffix tree can be seen as a type of state machine where each state is a
+/// substring of the full string. The tree is structured so that, for a string
+/// of length N, there are exactly N leaves in the tree. This structure allows
+/// us to quickly find repeated substrings of the input string.
+///
+/// In this implementation, a "string" is a vector of unsigned integers.
+/// These integers may result from hashing some data type. A suffix tree can
+/// contain 1 or many strings, which can then be queried as one large string.
+///
+/// The suffix tree is implemented using Ukkonen's algorithm for linear-time
+/// suffix tree construction. Ukkonen's algorithm is explained in more detail
+/// in the paper by Esko Ukkonen "On-line construction of suffix trees. The
+/// paper is available at
+///
+/// https://www.cs.helsinki.fi/u/ukkonen/SuffixT1withFigs.pdf
+class SuffixTree {
+private:
+ /// Each element is an integer representing an instruction in the module.
+ ArrayRef<unsigned> Str;
+
+ /// Maintains each node in the tree.
+ BumpPtrAllocator NodeAllocator;
+
+ /// The root of the suffix tree.
+ ///
+ /// The root represents the empty string. It is maintained by the
+ /// \p NodeAllocator like every other node in the tree.
+ SuffixTreeNode *Root = nullptr;
+
+ /// Stores each leaf in the tree for better pruning.
+ std::vector<SuffixTreeNode *> LeafVector;
+
+ /// Maintains the end indices of the internal nodes in the tree.
+ ///
+ /// Each internal node is guaranteed to never have its end index change
+ /// during the construction algorithm; however, leaves must be updated at
+ /// every step. Therefore, we need to store leaf end indices by reference
+ /// to avoid updating O(N) leaves at every step of construction. Thus,
+ /// every internal node must be allocated its own end index.
+ BumpPtrAllocator InternalEndIdxAllocator;
+
+ /// The end index of each leaf in the tree.
+ size_t LeafEndIdx = -1;
+
+ /// \brief Helper struct which keeps track of the next insertion point in
+ /// Ukkonen's algorithm.
+ struct ActiveState {
+ /// The next node to insert at.
+ SuffixTreeNode *Node;
+
+ /// The index of the first character in the substring currently being added.
+ size_t Idx = EmptyIdx;
+
+ /// The length of the substring we have to add at the current step.
+ size_t Len = 0;
+ };
+
+ /// \brief The point the next insertion will take place at in the
+ /// construction algorithm.
+ ActiveState Active;
+
+ /// Allocate a leaf node and add it to the tree.
+ ///
+ /// \param Parent The parent of this node.
+ /// \param StartIdx The start index of this node's associated string.
+ /// \param Edge The label on the edge leaving \p Parent to this node.
+ ///
+ /// \returns A pointer to the allocated leaf node.
+ SuffixTreeNode *insertLeaf(SuffixTreeNode &Parent, size_t StartIdx,
+ unsigned Edge) {
+
+ assert(StartIdx <= LeafEndIdx && "String can't start after it ends!");
+
+ SuffixTreeNode *N = new (NodeAllocator) SuffixTreeNode(StartIdx,
+ &LeafEndIdx,
+ nullptr,
+ &Parent);
+ Parent.Children[Edge] = N;
+
+ return N;
+ }
+
+ /// Allocate an internal node and add it to the tree.
+ ///
+ /// \param Parent The parent of this node. Only null when allocating the root.
+ /// \param StartIdx The start index of this node's associated string.
+ /// \param EndIdx The end index of this node's associated string.
+ /// \param Edge The label on the edge leaving \p Parent to this node.
+ ///
+ /// \returns A pointer to the allocated internal node.
+ SuffixTreeNode *insertInternalNode(SuffixTreeNode *Parent, size_t StartIdx,
+ size_t EndIdx, unsigned Edge) {
+
+ assert(StartIdx <= EndIdx && "String can't start after it ends!");
+ assert(!(!Parent && StartIdx != EmptyIdx) &&
+ "Non-root internal nodes must have parents!");
+
+ size_t *E = new (InternalEndIdxAllocator) size_t(EndIdx);
+ SuffixTreeNode *N = new (NodeAllocator) SuffixTreeNode(StartIdx,
+ E,
+ Root,
+ Parent);
+ if (Parent)
+ Parent->Children[Edge] = N;
+
+ return N;
+ }
+
+ /// \brief Set the suffix indices of the leaves to the start indices of their
+ /// respective suffixes. Also stores each leaf in \p LeafVector at its
+ /// respective suffix index.
+ ///
+ /// \param[in] CurrNode The node currently being visited.
+ /// \param CurrIdx The current index of the string being visited.
+ void setSuffixIndices(SuffixTreeNode &CurrNode, size_t CurrIdx) {
+
+ bool IsLeaf = CurrNode.Children.size() == 0 && !CurrNode.isRoot();
+
+ // Traverse the tree depth-first.
+ for (auto &ChildPair : CurrNode.Children) {
+ assert(ChildPair.second && "Node had a null child!");
+ setSuffixIndices(*ChildPair.second,
+ CurrIdx + ChildPair.second->size());
+ }
+
+ // Is this node a leaf?
+ if (IsLeaf) {
+ // If yes, give it a suffix index and bump its parent's occurrence count.
+ CurrNode.SuffixIdx = Str.size() - CurrIdx;
+ assert(CurrNode.Parent && "CurrNode had no parent!");
+ CurrNode.Parent->OccurrenceCount++;
+
+ // Store the leaf in the leaf vector for pruning later.
+ LeafVector[CurrNode.SuffixIdx] = &CurrNode;
+ }
+ }
+
+ /// \brief Construct the suffix tree for the prefix of the input ending at
+ /// \p EndIdx.
+ ///
+ /// Used to construct the full suffix tree iteratively. At the end of each
+ /// step, the constructed suffix tree is either a valid suffix tree, or a
+ /// suffix tree with implicit suffixes. At the end of the final step, the
+ /// suffix tree is a valid tree.
+ ///
+ /// \param EndIdx The end index of the current prefix in the main string.
+ /// \param SuffixesToAdd The number of suffixes that must be added
+ /// to complete the suffix tree at the current phase.
+ ///
+ /// \returns The number of suffixes that have not been added at the end of
+ /// this step.
+ unsigned extend(size_t EndIdx, size_t SuffixesToAdd) {
+ SuffixTreeNode *NeedsLink = nullptr;
+
+ while (SuffixesToAdd > 0) {
+
+ // Are we waiting to add anything other than just the last character?
+ if (Active.Len == 0) {
+ // If not, then say the active index is the end index.
+ Active.Idx = EndIdx;
+ }
+
+ assert(Active.Idx <= EndIdx && "Start index can't be after end index!");
+
+ // The first character in the current substring we're looking at.
+ unsigned FirstChar = Str[Active.Idx];
+
+ // Have we inserted anything starting with FirstChar at the current node?
+ if (Active.Node->Children.count(FirstChar) == 0) {
+ // If not, then we can just insert a leaf and move too the next step.
+ insertLeaf(*Active.Node, EndIdx, FirstChar);
+
+ // The active node is an internal node, and we visited it, so it must
+ // need a link if it doesn't have one.
+ if (NeedsLink) {
+ NeedsLink->Link = Active.Node;
+ NeedsLink = nullptr;
+ }
+ } else {
+ // There's a match with FirstChar, so look for the point in the tree to
+ // insert a new node.
+ SuffixTreeNode *NextNode = Active.Node->Children[FirstChar];
+
+ size_t SubstringLen = NextNode->size();
+
+ // Is the current suffix we're trying to insert longer than the size of
+ // the child we want to move to?
+ if (Active.Len >= SubstringLen) {
+ // If yes, then consume the characters we've seen and move to the next
+ // node.
+ Active.Idx += SubstringLen;
+ Active.Len -= SubstringLen;
+ Active.Node = NextNode;
+ continue;
+ }
+
+ // Otherwise, the suffix we're trying to insert must be contained in the
+ // next node we want to move to.
+ unsigned LastChar = Str[EndIdx];
+
+ // Is the string we're trying to insert a substring of the next node?
+ if (Str[NextNode->StartIdx + Active.Len] == LastChar) {
+ // If yes, then we're done for this step. Remember our insertion point
+ // and move to the next end index. At this point, we have an implicit
+ // suffix tree.
+ if (NeedsLink && !Active.Node->isRoot()) {
+ NeedsLink->Link = Active.Node;
+ NeedsLink = nullptr;
+ }
+
+ Active.Len++;
+ break;
+ }
+
+ // The string we're trying to insert isn't a substring of the next node,
+ // but matches up to a point. Split the node.
+ //
+ // For example, say we ended our search at a node n and we're trying to
+ // insert ABD. Then we'll create a new node s for AB, reduce n to just
+ // representing C, and insert a new leaf node l to represent d. This
+ // allows us to ensure that if n was a leaf, it remains a leaf.
+ //
+ // | ABC ---split---> | AB
+ // n s
+ // C / \ D
+ // n l
+
+ // The node s from the diagram
+ SuffixTreeNode *SplitNode =
+ insertInternalNode(Active.Node,
+ NextNode->StartIdx,
+ NextNode->StartIdx + Active.Len - 1,
+ FirstChar);
+
+ // Insert the new node representing the new substring into the tree as
+ // a child of the split node. This is the node l from the diagram.
+ insertLeaf(*SplitNode, EndIdx, LastChar);
+
+ // Make the old node a child of the split node and update its start
+ // index. This is the node n from the diagram.
+ NextNode->StartIdx += Active.Len;
+ NextNode->Parent = SplitNode;
+ SplitNode->Children[Str[NextNode->StartIdx]] = NextNode;
+
+ // SplitNode is an internal node, update the suffix link.
+ if (NeedsLink)
+ NeedsLink->Link = SplitNode;
+
+ NeedsLink = SplitNode;
+ }
+
+ // We've added something new to the tree, so there's one less suffix to
+ // add.
+ SuffixesToAdd--;
+
+ if (Active.Node->isRoot()) {
+ if (Active.Len > 0) {
+ Active.Len--;
+ Active.Idx = EndIdx - SuffixesToAdd + 1;
+ }
+ } else {
+ // Start the next phase at the next smallest suffix.
+ Active.Node = Active.Node->Link;
+ }
+ }
+
+ return SuffixesToAdd;
+ }
+
+ /// \brief Return the start index and length of a string which maximizes a
+ /// benefit function by traversing the tree depth-first.
+ ///
+ /// Helper function for \p bestRepeatedSubstring.
+ ///
+ /// \param CurrNode The node currently being visited.
+ /// \param CurrLen Length of the current string.
+ /// \param[out] BestLen Length of the most beneficial substring.
+ /// \param[out] MaxBenefit Benefit of the most beneficial substring.
+ /// \param[out] BestStartIdx Start index of the most beneficial substring.
+ /// \param BenefitFn The function the query should return a maximum string
+ /// for.
+ void findBest(SuffixTreeNode &CurrNode, size_t CurrLen, size_t &BestLen,
+ size_t &MaxBenefit, size_t &BestStartIdx,
+ const std::function<unsigned(SuffixTreeNode &, size_t CurrLen)>
+ &BenefitFn) {
+
+ if (!CurrNode.IsInTree)
+ return;
+
+ // Can we traverse further down the tree?
+ if (!CurrNode.isLeaf()) {
+ // If yes, continue the traversal.
+ for (auto &ChildPair : CurrNode.Children) {
+ if (ChildPair.second && ChildPair.second->IsInTree)
+ findBest(*ChildPair.second, CurrLen + ChildPair.second->size(),
+ BestLen, MaxBenefit, BestStartIdx, BenefitFn);
+ }
+ } else {
+ // We hit a leaf.
+ size_t StringLen = CurrLen - CurrNode.size();
+ unsigned Benefit = BenefitFn(CurrNode, StringLen);
+
+ // Did we do better than in the last step?
+ if (Benefit <= MaxBenefit)
+ return;
+
+ // We did better, so update the best string.
+ MaxBenefit = Benefit;
+ BestStartIdx = CurrNode.SuffixIdx;
+ BestLen = StringLen;
+ }
+ }
+
+public:
+
+ /// \brief Return a substring of the tree with maximum benefit if such a
+ /// substring exists.
+ ///
+ /// Clears the input vector and fills it with a maximum substring or empty.
+ ///
+ /// \param[in,out] Best The most beneficial substring in the tree. Empty
+ /// if it does not exist.
+ /// \param BenefitFn The function the query should return a maximum string
+ /// for.
+ void bestRepeatedSubstring(std::vector<unsigned> &Best,
+ const std::function<unsigned(SuffixTreeNode &, size_t CurrLen)>
+ &BenefitFn) {
+ Best.clear();
+ size_t Length = 0; // Becomes the length of the best substring.
+ size_t Benefit = 0; // Becomes the benefit of the best substring.
+ size_t StartIdx = 0; // Becomes the start index of the best substring.
+ findBest(*Root, 0, Length, Benefit, StartIdx, BenefitFn);
+
+ for (size_t Idx = 0; Idx < Length; Idx++)
+ Best.push_back(Str[Idx + StartIdx]);
+ }
+
+ /// Perform a depth-first search for \p QueryString on the suffix tree.
+ ///
+ /// \param QueryString The string to search for.
+ /// \param CurrIdx The current index in \p QueryString that is being matched
+ /// against.
+ /// \param CurrNode The suffix tree node being searched in.
+ ///
+ /// \returns A \p SuffixTreeNode that \p QueryString appears in if such a
+ /// node exists, and \p nullptr otherwise.
+ SuffixTreeNode *findString(const std::vector<unsigned> &QueryString,
+ size_t &CurrIdx, SuffixTreeNode *CurrNode) {
+
+ // The search ended at a nonexistent or pruned node. Quit.
+ if (!CurrNode || !CurrNode->IsInTree)
+ return nullptr;
+
+ unsigned Edge = QueryString[CurrIdx]; // The edge we want to move on.
+ SuffixTreeNode *NextNode = CurrNode->Children[Edge]; // Next node in query.
+
+ if (CurrNode->isRoot()) {
+ // If we're at the root we have to check if there's a child, and move to
+ // that child. Don't consume the character since \p Root represents the
+ // empty string.
+ if (NextNode && NextNode->IsInTree)
+ return findString(QueryString, CurrIdx, NextNode);
+ return nullptr;
+ }
+
+ size_t StrIdx = CurrNode->StartIdx;
+ size_t MaxIdx = QueryString.size();
+ bool ContinueSearching = false;
+
+ // Match as far as possible into the string. If there's a mismatch, quit.
+ for (; CurrIdx < MaxIdx; CurrIdx++, StrIdx++) {
+ Edge = QueryString[CurrIdx];
+
+ // We matched perfectly, but still have a remainder to search.
+ if (StrIdx > *(CurrNode->EndIdx)) {
+ ContinueSearching = true;
+ break;
+ }
+
+ if (Edge != Str[StrIdx])
+ return nullptr;
+ }
+
+ NextNode = CurrNode->Children[Edge];
+
+ // Move to the node which matches what we're looking for and continue
+ // searching.
+ if (ContinueSearching)
+ return findString(QueryString, CurrIdx, NextNode);
+
+ // We matched perfectly so we're done.
+ return CurrNode;
+ }
+
+ /// \brief Remove a node from a tree and all nodes representing proper
+ /// suffixes of that node's string.
+ ///
+ /// This is used in the outlining algorithm to reduce the number of
+ /// overlapping candidates
+ ///
+ /// \param N The suffix tree node to start pruning from.
+ /// \param Len The length of the string to be pruned.
+ ///
+ /// \returns True if this candidate didn't overlap with a previously chosen
+ /// candidate.
+ bool prune(SuffixTreeNode *N, size_t Len) {
+
+ bool NoOverlap = true;
+ std::vector<unsigned> IndicesToPrune;
+
+ // Look at each of N's children.
+ for (auto &ChildPair : N->Children) {
+ SuffixTreeNode *M = ChildPair.second;
+
+ // Is this a leaf child?
+ if (M && M->IsInTree && M->isLeaf()) {
+ // Save each leaf child's suffix indices and remove them from the tree.
+ IndicesToPrune.push_back(M->SuffixIdx);
+ M->IsInTree = false;
+ }
+ }
+
+ // Remove each suffix we have to prune from the tree. Each of these will be
+ // I + some offset for I in IndicesToPrune and some offset < Len.
+ unsigned Offset = 1;
+ for (unsigned CurrentSuffix = 1; CurrentSuffix < Len; CurrentSuffix++) {
+ for (unsigned I : IndicesToPrune) {
+
+ unsigned PruneIdx = I + Offset;
+
+ // Is this index actually in the string?
+ if (PruneIdx < LeafVector.size()) {
+ // If yes, we have to try and prune it.
+ // Was the current leaf already pruned by another candidate?
+ if (LeafVector[PruneIdx]->IsInTree) {
+ // If not, prune it.
+ LeafVector[PruneIdx]->IsInTree = false;
+ } else {
+ // If yes, signify that we've found an overlap, but keep pruning.
+ NoOverlap = false;
+ }
+
+ // Update the parent of the current leaf's occurrence count.
+ SuffixTreeNode *Parent = LeafVector[PruneIdx]->Parent;
+
+ // Is the parent still in the tree?
+ if (Parent->OccurrenceCount > 0) {
+ Parent->OccurrenceCount--;
+ Parent->IsInTree = (Parent->OccurrenceCount > 1);
+ }
+ }
+ }
+
+ // Move to the next character in the string.
+ Offset++;
+ }
+
+ // We know we can never outline anything which starts one index back from
+ // the indices we want to outline. This is because our minimum outlining
+ // length is always 2.
+ for (unsigned I : IndicesToPrune) {
+ if (I > 0) {
+
+ unsigned PruneIdx = I-1;
+ SuffixTreeNode *Parent = LeafVector[PruneIdx]->Parent;
+
+ // Was the leaf one index back from I already pruned?
+ if (LeafVector[PruneIdx]->IsInTree) {
+ // If not, prune it.
+ LeafVector[PruneIdx]->IsInTree = false;
+ } else {
+ // If yes, signify that we've found an overlap, but keep pruning.
+ NoOverlap = false;
+ }
+
+ // Update the parent of the current leaf's occurrence count.
+ if (Parent->OccurrenceCount > 0) {
+ Parent->OccurrenceCount--;
+ Parent->IsInTree = (Parent->OccurrenceCount > 1);
+ }
+ }
+ }
+
+ // Finally, remove N from the tree and set its occurrence count to 0.
+ N->IsInTree = false;
+ N->OccurrenceCount = 0;
+
+ return NoOverlap;
+ }
+
+ /// \brief Find each occurrence of of a string in \p QueryString and prune
+ /// their nodes.
+ ///
+ /// \param QueryString The string to search for.
+ /// \param[out] Occurrences The start indices of each occurrence.
+ ///
+ /// \returns Whether or not the occurrence overlaps with a previous candidate.
+ bool findOccurrencesAndPrune(const std::vector<unsigned> &QueryString,
+ std::vector<size_t> &Occurrences) {
+ size_t Dummy = 0;
+ SuffixTreeNode *N = findString(QueryString, Dummy, Root);
+
+ if (!N || !N->IsInTree)
+ return false;
+
+ // If this is an internal node, occurrences are the number of leaf children
+ // of the node.
+ for (auto &ChildPair : N->Children) {
+ SuffixTreeNode *M = ChildPair.second;
+
+ // Is it a leaf? If so, we have an occurrence.
+ if (M && M->IsInTree && M->isLeaf())
+ Occurrences.push_back(M->SuffixIdx);
+ }
+
+ // If we're in a leaf, then this node is the only occurrence.
+ if (N->isLeaf())
+ Occurrences.push_back(N->SuffixIdx);
+
+ return prune(N, QueryString.size());
+ }
+
+ /// Construct a suffix tree from a sequence of unsigned integers.
+ ///
+ /// \param Str The string to construct the suffix tree for.
+ SuffixTree(const std::vector<unsigned> &Str) : Str(Str) {
+ Root = insertInternalNode(nullptr, EmptyIdx, EmptyIdx, 0);
+ Root->IsInTree = true;
+ Active.Node = Root;
+ LeafVector = std::vector<SuffixTreeNode*>(Str.size());
+
+ // Keep track of the number of suffixes we have to add of the current
+ // prefix.
+ size_t SuffixesToAdd = 0;
+ Active.Node = Root;
+
+ // Construct the suffix tree iteratively on each prefix of the string.
+ // PfxEndIdx is the end index of the current prefix.
+ // End is one past the last element in the string.
+ for (size_t PfxEndIdx = 0, End = Str.size(); PfxEndIdx < End; PfxEndIdx++) {
+ SuffixesToAdd++;
+ LeafEndIdx = PfxEndIdx; // Extend each of the leaves.
+ SuffixesToAdd = extend(PfxEndIdx, SuffixesToAdd);
+ }
+
+ // Set the suffix indices of each leaf.
+ assert(Root && "Root node can't be nullptr!");
+ setSuffixIndices(*Root, 0);
+ }
+};
+
+/// \brief An individual sequence of instructions to be replaced with a call to
+/// an outlined function.
+struct Candidate {
+
+ /// Set to false if the candidate overlapped with another candidate.
+ bool InCandidateList = true;
+
+ /// The start index of this \p Candidate.
+ size_t StartIdx;
+
+ /// The number of instructions in this \p Candidate.
+ size_t Len;
+
+ /// The index of this \p Candidate's \p OutlinedFunction in the list of
+ /// \p OutlinedFunctions.
+ size_t FunctionIdx;
+
+ Candidate(size_t StartIdx, size_t Len, size_t FunctionIdx)
+ : StartIdx(StartIdx), Len(Len), FunctionIdx(FunctionIdx) {}
+
+ Candidate() {}
+
+ /// \brief Used to ensure that \p Candidates are outlined in an order that
+ /// preserves the start and end indices of other \p Candidates.
+ bool operator<(const Candidate &RHS) const { return StartIdx > RHS.StartIdx; }
+};
+
+/// \brief The information necessary to create an outlined function for some
+/// class of candidate.
+struct OutlinedFunction {
+
+ /// The actual outlined function created.
+ /// This is initialized after we go through and create the actual function.
+ MachineFunction *MF = nullptr;
+
+ /// A number assigned to this function which appears at the end of its name.
+ size_t Name;
+
+ /// The number of times that this function has appeared.
+ size_t OccurrenceCount = 0;
+
+ /// \brief The sequence of integers corresponding to the instructions in this
+ /// function.
+ std::vector<unsigned> Sequence;
+
+ /// The number of instructions this function would save.
+ unsigned Benefit = 0;
+
+ OutlinedFunction(size_t Name, size_t OccurrenceCount,
+ const std::vector<unsigned> &Sequence,
+ unsigned Benefit)
+ : Name(Name), OccurrenceCount(OccurrenceCount), Sequence(Sequence),
+ Benefit(Benefit)
+ {}
+};
+
+/// \brief Maps \p MachineInstrs to unsigned integers and stores the mappings.
+struct InstructionMapper {
+
+ /// \brief The next available integer to assign to a \p MachineInstr that
+ /// cannot be outlined.
+ ///
+ /// Set to -3 for compatability with \p DenseMapInfo<unsigned>.
+ unsigned IllegalInstrNumber = -3;
+
+ /// \brief The next available integer to assign to a \p MachineInstr that can
+ /// be outlined.
+ unsigned LegalInstrNumber = 0;
+
+ /// Correspondence from \p MachineInstrs to unsigned integers.
+ DenseMap<MachineInstr *, unsigned, MachineInstrExpressionTrait>
+ InstructionIntegerMap;
+
+ /// Corresponcence from unsigned integers to \p MachineInstrs.
+ /// Inverse of \p InstructionIntegerMap.
+ DenseMap<unsigned, MachineInstr *> IntegerInstructionMap;
+
+ /// The vector of unsigned integers that the module is mapped to.
+ std::vector<unsigned> UnsignedVec;
+
+ /// \brief Stores the location of the instruction associated with the integer
+ /// at index i in \p UnsignedVec for each index i.
+ std::vector<MachineBasicBlock::iterator> InstrList;
+
+ /// \brief Maps \p *It to a legal integer.
+ ///
+ /// Updates \p InstrList, \p UnsignedVec, \p InstructionIntegerMap,
+ /// \p IntegerInstructionMap, and \p LegalInstrNumber.
+ ///
+ /// \returns The integer that \p *It was mapped to.
+ unsigned mapToLegalUnsigned(MachineBasicBlock::iterator &It) {
+
+ // Get the integer for this instruction or give it the current
+ // LegalInstrNumber.
+ InstrList.push_back(It);
+ MachineInstr &MI = *It;
+ bool WasInserted;
+ DenseMap<MachineInstr *, unsigned, MachineInstrExpressionTrait>::iterator
+ ResultIt;
+ std::tie(ResultIt, WasInserted) =
+ InstructionIntegerMap.insert(std::make_pair(&MI, LegalInstrNumber));
+ unsigned MINumber = ResultIt->second;
+
+ // There was an insertion.
+ if (WasInserted) {
+ LegalInstrNumber++;
+ IntegerInstructionMap.insert(std::make_pair(MINumber, &MI));
+ }
+
+ UnsignedVec.push_back(MINumber);
+
+ // Make sure we don't overflow or use any integers reserved by the DenseMap.
+ if (LegalInstrNumber >= IllegalInstrNumber)
+ report_fatal_error("Instruction mapping overflow!");
+
+ assert(LegalInstrNumber != DenseMapInfo<unsigned>::getEmptyKey()
+ && "Tried to assign DenseMap tombstone or empty key to instruction.");
+ assert(LegalInstrNumber != DenseMapInfo<unsigned>::getTombstoneKey()
+ && "Tried to assign DenseMap tombstone or empty key to instruction.");
+
+ return MINumber;
+ }
+
+ /// Maps \p *It to an illegal integer.
+ ///
+ /// Updates \p InstrList, \p UnsignedVec, and \p IllegalInstrNumber.
+ ///
+ /// \returns The integer that \p *It was mapped to.
+ unsigned mapToIllegalUnsigned(MachineBasicBlock::iterator &It) {
+ unsigned MINumber = IllegalInstrNumber;
+
+ InstrList.push_back(It);
+ UnsignedVec.push_back(IllegalInstrNumber);
+ IllegalInstrNumber--;
+
+ assert(LegalInstrNumber < IllegalInstrNumber &&
+ "Instruction mapping overflow!");
+
+ assert(IllegalInstrNumber !=
+ DenseMapInfo<unsigned>::getEmptyKey() &&
+ "IllegalInstrNumber cannot be DenseMap tombstone or empty key!");
+
+ assert(IllegalInstrNumber !=
+ DenseMapInfo<unsigned>::getTombstoneKey() &&
+ "IllegalInstrNumber cannot be DenseMap tombstone or empty key!");
+
+ return MINumber;
+ }
+
+ /// \brief Transforms a \p MachineBasicBlock into a \p vector of \p unsigneds
+ /// and appends it to \p UnsignedVec and \p InstrList.
+ ///
+ /// Two instructions are assigned the same integer if they are identical.
+ /// If an instruction is deemed unsafe to outline, then it will be assigned an
+ /// unique integer. The resulting mapping is placed into a suffix tree and
+ /// queried for candidates.
+ ///
+ /// \param MBB The \p MachineBasicBlock to be translated into integers.
+ /// \param TRI \p TargetRegisterInfo for the module.
+ /// \param TII \p TargetInstrInfo for the module.
+ void convertToUnsignedVec(MachineBasicBlock &MBB,
+ const TargetRegisterInfo &TRI,
+ const TargetInstrInfo &TII) {
+ for (MachineBasicBlock::iterator It = MBB.begin(), Et = MBB.end(); It != Et;
+ It++) {
+
+ // Keep track of where this instruction is in the module.
+ switch(TII.getOutliningType(*It)) {
+ case TargetInstrInfo::MachineOutlinerInstrType::Illegal:
+ mapToIllegalUnsigned(It);
+ break;
+
+ case TargetInstrInfo::MachineOutlinerInstrType::Legal:
+ mapToLegalUnsigned(It);
+ break;
+
+ case TargetInstrInfo::MachineOutlinerInstrType::Invisible:
+ break;
+ }
+ }
+
+ // After we're done every insertion, uniquely terminate this part of the
+ // "string". This makes sure we won't match across basic block or function
+ // boundaries since the "end" is encoded uniquely and thus appears in no
+ // repeated substring.
+ InstrList.push_back(MBB.end());
+ UnsignedVec.push_back(IllegalInstrNumber);
+ IllegalInstrNumber--;
+ }
+
+ InstructionMapper() {
+ // Make sure that the implementation of DenseMapInfo<unsigned> hasn't
+ // changed.
+ assert(DenseMapInfo<unsigned>::getEmptyKey() == (unsigned)-1 &&
+ "DenseMapInfo<unsigned>'s empty key isn't -1!");
+ assert(DenseMapInfo<unsigned>::getTombstoneKey() == (unsigned)-2 &&
+ "DenseMapInfo<unsigned>'s tombstone key isn't -2!");
+ }
+};
+
+/// \brief An interprocedural pass which finds repeated sequences of
+/// instructions and replaces them with calls to functions.
+///
+/// Each instruction is mapped to an unsigned integer and placed in a string.
+/// The resulting mapping is then placed in a \p SuffixTree. The \p SuffixTree
+/// is then repeatedly queried for repeated sequences of instructions. Each
+/// non-overlapping repeated sequence is then placed in its own
+/// \p MachineFunction and each instance is then replaced with a call to that
+/// function.
+struct MachineOutliner : public ModulePass {
+
+ static char ID;
+
+ StringRef getPassName() const override { return "Machine Outliner"; }
+
+ void getAnalysisUsage(AnalysisUsage &AU) const override {
+ AU.addRequired<MachineModuleInfo>();
+ AU.addPreserved<MachineModuleInfo>();
+ AU.setPreservesAll();
+ ModulePass::getAnalysisUsage(AU);
+ }
+
+ MachineOutliner() : ModulePass(ID) {
+ initializeMachineOutlinerPass(*PassRegistry::getPassRegistry());
+ }
+
+ /// \brief Replace the sequences of instructions represented by the
+ /// \p Candidates in \p CandidateList with calls to \p MachineFunctions
+ /// described in \p FunctionList.
+ ///
+ /// \param M The module we are outlining from.
+ /// \param CandidateList A list of candidates to be outlined.
+ /// \param FunctionList A list of functions to be inserted into the module.
+ /// \param Mapper Contains the instruction mappings for the module.
+ bool outline(Module &M, const ArrayRef<Candidate> &CandidateList,
+ std::vector<OutlinedFunction> &FunctionList,
+ InstructionMapper &Mapper);
+
+ /// Creates a function for \p OF and inserts it into the module.
+ MachineFunction *createOutlinedFunction(Module &M, const OutlinedFunction &OF,
+ InstructionMapper &Mapper);
+
+ /// Find potential outlining candidates and store them in \p CandidateList.
+ ///
+ /// For each type of potential candidate, also build an \p OutlinedFunction
+ /// struct containing the information to build the function for that
+ /// candidate.
+ ///
+ /// \param[out] CandidateList Filled with outlining candidates for the module.
+ /// \param[out] FunctionList Filled with functions corresponding to each type
+ /// of \p Candidate.
+ /// \param ST The suffix tree for the module.
+ /// \param TII TargetInstrInfo for the module.
+ ///
+ /// \returns The length of the longest candidate found. 0 if there are none.
+ unsigned buildCandidateList(std::vector<Candidate> &CandidateList,
+ std::vector<OutlinedFunction> &FunctionList,
+ SuffixTree &ST, const TargetInstrInfo &TII);
+
+ /// \brief Remove any overlapping candidates that weren't handled by the
+ /// suffix tree's pruning method.
+ ///
+ /// Pruning from the suffix tree doesn't necessarily remove all overlaps.
+ /// If a short candidate is chosen for outlining, then a longer candidate
+ /// which has that short candidate as a suffix is chosen, the tree's pruning
+ /// method will not find it. Thus, we need to prune before outlining as well.
+ ///
+ /// \param[in,out] CandidateList A list of outlining candidates.
+ /// \param[in,out] FunctionList A list of functions to be outlined.
+ /// \param MaxCandidateLen The length of the longest candidate.
+ /// \param TII TargetInstrInfo for the module.
+ void pruneOverlaps(std::vector<Candidate> &CandidateList,
+ std::vector<OutlinedFunction> &FunctionList,
+ unsigned MaxCandidateLen,
+ const TargetInstrInfo &TII);
+
+ /// Construct a suffix tree on the instructions in \p M and outline repeated
+ /// strings from that tree.
+ bool runOnModule(Module &M) override;
+};
+
+} // Anonymous namespace.
+
+char MachineOutliner::ID = 0;
+
+namespace llvm {
+ModulePass *createMachineOutlinerPass() { return new MachineOutliner(); }
+}
+
+INITIALIZE_PASS(MachineOutliner, "machine-outliner",
+ "Machine Function Outliner", false, false)
+
+void MachineOutliner::pruneOverlaps(std::vector<Candidate> &CandidateList,
+ std::vector<OutlinedFunction> &FunctionList,
+ unsigned MaxCandidateLen,
+ const TargetInstrInfo &TII) {
+
+ // Check for overlaps in the range. This is O(n^2) worst case, but we can
+ // alleviate that somewhat by bounding our search space using the start
+ // index of our first candidate and the maximum distance an overlapping
+ // candidate could have from the first candidate.
+ for (auto It = CandidateList.begin(), Et = CandidateList.end(); It != Et;
+ It++) {
+ Candidate &C1 = *It;
+ OutlinedFunction &F1 = FunctionList[C1.FunctionIdx];
+
+ // If we removed this candidate, skip it.
+ if (!C1.InCandidateList)
+ continue;
+
+ // If the candidate's function isn't good to outline anymore, then
+ // remove the candidate and skip it.
+ if (F1.OccurrenceCount < 2 || F1.Benefit < 1) {
+ C1.InCandidateList = false;
+ continue;
+ }
+
+ // The minimum start index of any candidate that could overlap with this
+ // one.
+ unsigned FarthestPossibleIdx = 0;
+
+ // Either the index is 0, or it's at most MaxCandidateLen indices away.
+ if (C1.StartIdx > MaxCandidateLen)
+ FarthestPossibleIdx = C1.StartIdx - MaxCandidateLen;
+
+ // Compare against the other candidates in the list.
+ // This is at most MaxCandidateLen/2 other candidates.
+ // This is because each candidate has to be at least 2 indices away.
+ // = O(n * MaxCandidateLen/2) comparisons
+ //
+ // On average, the maximum length of a candidate is quite small; a fraction
+ // of the total module length in terms of instructions. If the maximum
+ // candidate length is large, then there are fewer possible candidates to
+ // compare against in the first place.
+ for (auto Sit = It + 1; Sit != Et; Sit++) {
+ Candidate &C2 = *Sit;
+ OutlinedFunction &F2 = FunctionList[C2.FunctionIdx];
+
+ // Is this candidate too far away to overlap?
+ // NOTE: This will be true in
+ // O(max(FarthestPossibleIdx/2, #Candidates remaining)) steps
+ // for every candidate.
+ if (C2.StartIdx < FarthestPossibleIdx)
+ break;
+
+ // Did we already remove this candidate in a previous step?
+ if (!C2.InCandidateList)
+ continue;
+
+ // Is the function beneficial to outline?
+ if (F2.OccurrenceCount < 2 || F2.Benefit < 1) {
+ // If not, remove this candidate and move to the next one.
+ C2.InCandidateList = false;
+ continue;
+ }
+
+ size_t C2End = C2.StartIdx + C2.Len - 1;
+
+ // Do C1 and C2 overlap?
+ //
+ // Not overlapping:
+ // High indices... [C1End ... C1Start][C2End ... C2Start] ...Low indices
+ //
+ // We sorted our candidate list so C2Start <= C1Start. We know that
+ // C2End > C2Start since each candidate has length >= 2. Therefore, all we
+ // have to check is C2End < C2Start to see if we overlap.
+ if (C2End < C1.StartIdx)
+ continue;
+
+ // C2 overlaps with C1. Because we pruned the tree already, the only way
+ // this can happen is if C1 is a proper suffix of C2. Thus, we must have
+ // found C1 first during our query, so it must have benefit greater or
+ // equal to C2. Greedily pick C1 as the candidate to keep and toss out C2.
+ DEBUG (
+ size_t C1End = C1.StartIdx + C1.Len - 1;
+ dbgs() << "- Found an overlap to purge.\n";
+ dbgs() << "--- C1 :[" << C1.StartIdx << ", " << C1End << "]\n";
+ dbgs() << "--- C2 :[" << C2.StartIdx << ", " << C2End << "]\n";
+ );
+
+ // Update the function's occurrence count and benefit to reflec that C2
+ // is being removed.
+ F2.OccurrenceCount--;
+ F2.Benefit = TII.getOutliningBenefit(F2.Sequence.size(),
+ F2.OccurrenceCount
+ );
+
+ // Mark C2 as not in the list.
+ C2.InCandidateList = false;
+
+ DEBUG (
+ dbgs() << "- Removed C2. \n";
+ dbgs() << "--- Num fns left for C2: " << F2.OccurrenceCount << "\n";
+ dbgs() << "--- C2's benefit: " << F2.Benefit << "\n";
+ );
+ }
+ }
+}
+
+unsigned
+MachineOutliner::buildCandidateList(std::vector<Candidate> &CandidateList,
+ std::vector<OutlinedFunction> &FunctionList,
+ SuffixTree &ST,
+ const TargetInstrInfo &TII) {
+
+ std::vector<unsigned> CandidateSequence; // Current outlining candidate.
+ unsigned MaxCandidateLen = 0; // Length of the longest candidate.
+
+ // Function for maximizing query in the suffix tree.
+ // This allows us to define more fine-grained types of things to outline in
+ // the target without putting target-specific info in the suffix tree.
+ auto BenefitFn = [&TII](const SuffixTreeNode &Curr, size_t StringLen) {
+
+ // Any leaf whose parent is the root only has one occurrence.
+ if (Curr.Parent->isRoot())
+ return 0u;
+
+ // Anything with length < 2 will never be beneficial on any target.
+ if (StringLen < 2)
+ return 0u;
+
+ size_t Occurrences = Curr.Parent->OccurrenceCount;
+
+ // Anything with fewer than 2 occurrences will never be beneficial on any
+ // target.
+ if (Occurrences < 2)
+ return 0u;
+
+ return TII.getOutliningBenefit(StringLen, Occurrences);
+ };
+
+ // Repeatedly query the suffix tree for the substring that maximizes
+ // BenefitFn. Find the occurrences of that string, prune the tree, and store
+ // each occurrence as a candidate.
+ for (ST.bestRepeatedSubstring(CandidateSequence, BenefitFn);
+ CandidateSequence.size() > 1;
+ ST.bestRepeatedSubstring(CandidateSequence, BenefitFn)) {
+
+ std::vector<size_t> Occurrences;
+
+ bool GotNonOverlappingCandidate =
+ ST.findOccurrencesAndPrune(CandidateSequence, Occurrences);
+
+ // Is the candidate we found known to overlap with something we already
+ // outlined?
+ if (!GotNonOverlappingCandidate)
+ continue;
+
+ // Is this candidate the longest so far?
+ if (CandidateSequence.size() > MaxCandidateLen)
+ MaxCandidateLen = CandidateSequence.size();
+
+ // Keep track of the benefit of outlining this candidate in its
+ // OutlinedFunction.
+ unsigned FnBenefit = TII.getOutliningBenefit(CandidateSequence.size(),
+ Occurrences.size()
+ );
+
+ assert(FnBenefit > 0 && "Function cannot be unbeneficial!");
+
+ // Save an OutlinedFunction for this candidate.
+ FunctionList.emplace_back(
+ FunctionList.size(), // Number of this function.
+ Occurrences.size(), // Number of occurrences.
+ CandidateSequence, // Sequence to outline.
+ FnBenefit // Instructions saved by outlining this function.
+ );
+
+ // Save each of the occurrences of the candidate so we can outline them.
+ for (size_t &Occ : Occurrences)
+ CandidateList.emplace_back(
+ Occ, // Starting idx in that MBB.
+ CandidateSequence.size(), // Candidate length.
+ FunctionList.size() - 1 // Idx of the corresponding function.
+ );
+
+ FunctionsCreated++;
+ }
+
+ // Sort the candidates in decending order. This will simplify the outlining
+ // process when we have to remove the candidates from the mapping by
+ // allowing us to cut them out without keeping track of an offset.
+ std::stable_sort(CandidateList.begin(), CandidateList.end());
+
+ return MaxCandidateLen;
+}
+
+MachineFunction *
+MachineOutliner::createOutlinedFunction(Module &M, const OutlinedFunction &OF,
+ InstructionMapper &Mapper) {
+
+ // Create the function name. This should be unique. For now, just hash the
+ // module name and include it in the function name plus the number of this
+ // function.
+ std::ostringstream NameStream;
+ NameStream << "OUTLINED_FUNCTION" << "_" << OF.Name;
+
+ // Create the function using an IR-level function.
+ LLVMContext &C = M.getContext();
+ Function *F = dyn_cast<Function>(
+ M.getOrInsertFunction(NameStream.str(), Type::getVoidTy(C), NULL));
+ assert(F && "Function was null!");
+
+ // NOTE: If this is linkonceodr, then we can take advantage of linker deduping
+ // which gives us better results when we outline from linkonceodr functions.
+ F->setLinkage(GlobalValue::PrivateLinkage);
+ F->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
+
+ BasicBlock *EntryBB = BasicBlock::Create(C, "entry", F);
+ IRBuilder<> Builder(EntryBB);
+ Builder.CreateRetVoid();
+
+ MachineModuleInfo &MMI = getAnalysis<MachineModuleInfo>();
+ MachineFunction &MF = MMI.getMachineFunction(*F);
+ MachineBasicBlock &MBB = *MF.CreateMachineBasicBlock();
+ const TargetSubtargetInfo &STI = MF.getSubtarget();
+ const TargetInstrInfo &TII = *STI.getInstrInfo();
+
+ // Insert the new function into the module.
+ MF.insert(MF.begin(), &MBB);
+
+ TII.insertOutlinerPrologue(MBB, MF);
+
+ // Copy over the instructions for the function using the integer mappings in
+ // its sequence.
+ for (unsigned Str : OF.Sequence) {
+ MachineInstr *NewMI =
+ MF.CloneMachineInstr(Mapper.IntegerInstructionMap.find(Str)->second);
+ NewMI->dropMemRefs();
+
+ // Don't keep debug information for outlined instructions.
+ // FIXME: This means outlined functions are currently undebuggable.
+ NewMI->setDebugLoc(DebugLoc());
+ MBB.insert(MBB.end(), NewMI);
+ }
+
+ TII.insertOutlinerEpilogue(MBB, MF);
+
+ return &MF;
+}
+
+bool MachineOutliner::outline(Module &M,
+ const ArrayRef<Candidate> &CandidateList,
+ std::vector<OutlinedFunction> &FunctionList,
+ InstructionMapper &Mapper) {
+
+ bool OutlinedSomething = false;
+
+ // Replace the candidates with calls to their respective outlined functions.
+ for (const Candidate &C : CandidateList) {
+
+ // Was the candidate removed during pruneOverlaps?
+ if (!C.InCandidateList)
+ continue;
+
+ // If not, then look at its OutlinedFunction.
+ OutlinedFunction &OF = FunctionList[C.FunctionIdx];
+
+ // Was its OutlinedFunction made unbeneficial during pruneOverlaps?
+ if (OF.OccurrenceCount < 2 || OF.Benefit < 1)
+ continue;
+
+ // If not, then outline it.
+ assert(C.StartIdx < Mapper.InstrList.size() && "Candidate out of bounds!");
+ MachineBasicBlock *MBB = (*Mapper.InstrList[C.StartIdx]).getParent();
+ MachineBasicBlock::iterator StartIt = Mapper.InstrList[C.StartIdx];
+ unsigned EndIdx = C.StartIdx + C.Len - 1;
+
+ assert(EndIdx < Mapper.InstrList.size() && "Candidate out of bounds!");
+ MachineBasicBlock::iterator EndIt = Mapper.InstrList[EndIdx];
+ assert(EndIt != MBB->end() && "EndIt out of bounds!");
+
+ EndIt++; // Erase needs one past the end index.
+
+ // Does this candidate have a function yet?
+ if (!OF.MF)
+ OF.MF = createOutlinedFunction(M, OF, Mapper);
+
+ MachineFunction *MF = OF.MF;
+ const TargetSubtargetInfo &STI = MF->getSubtarget();
+ const TargetInstrInfo &TII = *STI.getInstrInfo();
+
+ // Insert a call to the new function and erase the old sequence.
+ TII.insertOutlinedCall(M, *MBB, StartIt, *MF);
+ StartIt = Mapper.InstrList[C.StartIdx];
+ MBB->erase(StartIt, EndIt);
+
+ OutlinedSomething = true;
+
+ // Statistics.
+ NumOutlined++;
+ }
+
+ DEBUG (
+ dbgs() << "OutlinedSomething = " << OutlinedSomething << "\n";
+ );
+
+ return OutlinedSomething;
+}
+
+bool MachineOutliner::runOnModule(Module &M) {
+
+ // Is there anything in the module at all?
+ if (M.empty())
+ return false;
+
+ MachineModuleInfo &MMI = getAnalysis<MachineModuleInfo>();
+ const TargetSubtargetInfo &STI = MMI.getMachineFunction(*M.begin())
+ .getSubtarget();
+ const TargetRegisterInfo *TRI = STI.getRegisterInfo();
+ const TargetInstrInfo *TII = STI.getInstrInfo();
+
+ InstructionMapper Mapper;
+
+ // Build instruction mappings for each function in the module.
+ for (Function &F : M) {
+ MachineFunction &MF = MMI.getMachineFunction(F);
+
+ // Is the function empty? Safe to outline from?
+ if (F.empty() || !TII->isFunctionSafeToOutlineFrom(MF))
+ continue;
+
+ // If it is, look at each MachineBasicBlock in the function.
+ for (MachineBasicBlock &MBB : MF) {
+
+ // Is there anything in MBB?
+ if (MBB.empty())
+ continue;
+
+ // If yes, map it.
+ Mapper.convertToUnsignedVec(MBB, *TRI, *TII);
+ }
+ }
+
+ // Construct a suffix tree, use it to find candidates, and then outline them.
+ SuffixTree ST(Mapper.UnsignedVec);
+ std::vector<Candidate> CandidateList;
+ std::vector<OutlinedFunction> FunctionList;
+
+ unsigned MaxCandidateLen =
+ buildCandidateList(CandidateList, FunctionList, ST, *TII);
+
+ pruneOverlaps(CandidateList, FunctionList, MaxCandidateLen, *TII);
+ return outline(M, CandidateList, FunctionList, Mapper);
+}
Modified: llvm/trunk/lib/CodeGen/TargetPassConfig.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/TargetPassConfig.cpp?rev=297081&r1=297080&r2=297081&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/TargetPassConfig.cpp (original)
+++ llvm/trunk/lib/CodeGen/TargetPassConfig.cpp Mon Mar 6 15:31:18 2017
@@ -92,6 +92,9 @@ static cl::opt<bool> VerifyMachineCode("
cl::desc("Verify generated machine code"),
cl::init(false),
cl::ZeroOrMore);
+static cl::opt<bool> EnableMachineOutliner("enable-machine-outliner",
+ cl::Hidden,
+ cl::desc("Enable machine outliner"));
static cl::opt<std::string>
PrintMachineInstrs("print-machineinstrs", cl::ValueOptional,
@@ -674,6 +677,9 @@ void TargetPassConfig::addMachinePasses(
addPass(&XRayInstrumentationID, false);
addPass(&PatchableFunctionID, false);
+ if (EnableMachineOutliner)
+ PM->add(createMachineOutlinerPass());
+
AddingMachinePasses = false;
}
Modified: llvm/trunk/lib/Target/X86/X86InstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrInfo.cpp?rev=297081&r1=297080&r2=297081&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86InstrInfo.cpp Mon Mar 6 15:31:18 2017
@@ -10383,3 +10383,83 @@ namespace {
char LDTLSCleanup::ID = 0;
FunctionPass*
llvm::createCleanupLocalDynamicTLSPass() { return new LDTLSCleanup(); }
+
+unsigned X86InstrInfo::getOutliningBenefit(size_t SequenceSize,
+ size_t Occurrences) const {
+ unsigned NotOutlinedSize = SequenceSize * Occurrences;
+
+ // Sequence appears once in outlined function (Sequence.size())
+ // One return instruction (+1)
+ // One call per occurrence (Occurrences)
+ unsigned OutlinedSize = (SequenceSize + 1) + Occurrences;
+
+ // Return the number of instructions saved by outlining this sequence.
+ return NotOutlinedSize > OutlinedSize ? NotOutlinedSize - OutlinedSize : 0;
+}
+
+bool X86InstrInfo::isFunctionSafeToOutlineFrom(MachineFunction &MF) const {
+ return MF.getFunction()->hasFnAttribute(Attribute::NoRedZone);
+}
+
+X86GenInstrInfo::MachineOutlinerInstrType
+X86InstrInfo::getOutliningType(MachineInstr &MI) const {
+
+ // Don't outline returns or basic block terminators.
+ if (MI.isReturn() || MI.isTerminator())
+ return MachineOutlinerInstrType::Illegal;
+
+ // Don't outline anything that modifies or reads from the stack pointer.
+ //
+ // FIXME: There are instructions which are being manually built without
+ // explicit uses/defs so we also have to check the MCInstrDesc. We should be
+ // able to remove the extra checks once those are fixed up. For example,
+ // sometimes we might get something like %RAX<def> = POP64r 1. This won't be
+ // caught by modifiesRegister or readsRegister even though the instruction
+ // really ought to be formed so that modifiesRegister/readsRegister would
+ // catch it.
+ if (MI.modifiesRegister(X86::RSP, &RI) || MI.readsRegister(X86::RSP, &RI) ||
+ MI.getDesc().hasImplicitUseOfPhysReg(X86::RSP) ||
+ MI.getDesc().hasImplicitDefOfPhysReg(X86::RSP))
+ return MachineOutlinerInstrType::Illegal;
+
+ if (MI.readsRegister(X86::RIP, &RI) ||
+ MI.getDesc().hasImplicitUseOfPhysReg(X86::RIP) ||
+ MI.getDesc().hasImplicitDefOfPhysReg(X86::RIP))
+ return MachineOutlinerInstrType::Illegal;
+
+ if (MI.isPosition())
+ return MachineOutlinerInstrType::Illegal;
+
+ for (const MachineOperand &MOP : MI.operands())
+ if (MOP.isCPI() || MOP.isJTI() || MOP.isCFIIndex() || MOP.isFI() ||
+ MOP.isTargetIndex())
+ return MachineOutlinerInstrType::Illegal;
+
+ // Don't allow debug values to impact outlining type.
+ if (MI.isDebugValue() || MI.isIndirectDebugValue())
+ return MachineOutlinerInstrType::Invisible;
+
+ return MachineOutlinerInstrType::Legal;
+}
+
+void X86InstrInfo::insertOutlinerEpilogue(MachineBasicBlock &MBB,
+ MachineFunction &MF) const {
+
+ MachineInstr *retq = BuildMI(MF, DebugLoc(), get(X86::RETQ));
+ MBB.insert(MBB.end(), retq);
+}
+
+void X86InstrInfo::insertOutlinerPrologue(MachineBasicBlock &MBB,
+ MachineFunction &MF) const {
+ return;
+}
+
+MachineBasicBlock::iterator
+X86InstrInfo::insertOutlinedCall(Module &M, MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &It,
+ MachineFunction &MF) const {
+ It = MBB.insert(It,
+ BuildMI(MF, DebugLoc(), get(X86::CALL64pcrel32))
+ .addGlobalAddress(M.getNamedValue(MF.getName())));
+ return It;
+}
Modified: llvm/trunk/lib/Target/X86/X86InstrInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrInfo.h?rev=297081&r1=297080&r2=297081&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrInfo.h (original)
+++ llvm/trunk/lib/Target/X86/X86InstrInfo.h Mon Mar 6 15:31:18 2017
@@ -545,6 +545,25 @@ public:
bool isTailCall(const MachineInstr &Inst) const override;
+ unsigned getOutliningBenefit(size_t SequenceSize,
+ size_t Occurrences) const override;
+
+ bool isFunctionSafeToOutlineFrom(MachineFunction &MF) const override;
+
+ llvm::X86GenInstrInfo::MachineOutlinerInstrType
+ getOutliningType(MachineInstr &MI) const override;
+
+ void insertOutlinerEpilogue(MachineBasicBlock &MBB,
+ MachineFunction &MF) const override;
+
+ void insertOutlinerPrologue(MachineBasicBlock &MBB,
+ MachineFunction &MF) const override;
+
+ MachineBasicBlock::iterator
+ insertOutlinedCall(Module &M, MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &It,
+ MachineFunction &MF) const override;
+
protected:
/// Commutes the operands in the given instruction by changing the operands
/// order and/or changing the instruction's opcode and/or the immediate value
Added: llvm/trunk/test/CodeGen/X86/machine-outliner-debuginfo.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/machine-outliner-debuginfo.ll?rev=297081&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/machine-outliner-debuginfo.ll (added)
+++ llvm/trunk/test/CodeGen/X86/machine-outliner-debuginfo.ll Mon Mar 6 15:31:18 2017
@@ -0,0 +1,75 @@
+; RUN: llc -enable-machine-outliner -mtriple=x86_64-apple-darwin < %s | FileCheck %s
+
+ at x = global i32 0, align 4, !dbg !0
+
+define i32 @main() #0 !dbg !11 {
+ ; CHECK-LABEL: _main:
+ %1 = alloca i32, align 4
+ %2 = alloca i32, align 4
+ %3 = alloca i32, align 4
+ %4 = alloca i32, align 4
+ %5 = alloca i32, align 4
+ ; There is a debug value in the middle of this section, make sure debug values are ignored.
+ ; CHECK: callq l_OUTLINED_FUNCTION_0
+ store i32 1, i32* %2, align 4
+ store i32 2, i32* %3, align 4
+ store i32 3, i32* %4, align 4
+ call void @llvm.dbg.value(metadata i32 10, i64 0, metadata !15, metadata !16), !dbg !17
+ store i32 4, i32* %5, align 4
+ store i32 0, i32* @x, align 4, !dbg !24
+ ; This is the same sequence of instructions without a debug value. It should be outlined
+ ; in the same way.
+ ; CHECK: callq l_OUTLINED_FUNCTION_0
+ store i32 1, i32* %2, align 4
+ store i32 2, i32* %3, align 4
+ store i32 3, i32* %4, align 4
+ store i32 4, i32* %5, align 4
+ store i32 1, i32* @x, align 4, !dbg !14
+ ret i32 0, !dbg !25
+}
+
+; CHECK-LABEL: l_OUTLINED_FUNCTION_0:
+; CHECK-NOT: .loc {{[0-9]+}} {{[0-9]+}} {{[0-9]+}} {{^(is_stmt)}}
+; CHECK-NOT: ##DEBUG_VALUE: main:{{[a-z]}} <- {{[0-9]+}}
+; CHECK: movl $1, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $2, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $3, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $4, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: retq
+
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
+
+declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1
+
+attributes #0 = { noredzone nounwind ssp uwtable "no-frame-pointer-elim"="true" }
+
+!llvm.dbg.cu = !{!2}
+!llvm.module.flags = !{!7, !8, !9}
+!llvm.ident = !{!10}
+
+!0 = !DIGlobalVariableExpression(var: !1)
+!1 = distinct !DIGlobalVariable(name: "x", scope: !2, file: !3, line: 2, type: !6, isLocal: false, isDefinition: true)
+!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang version 5.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5)
+!3 = !DIFile(filename: "debug-test.c", directory: "dir")
+!4 = !{}
+!5 = !{!0}
+!6 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!7 = !{i32 2, !"Dwarf Version", i32 4}
+!8 = !{i32 2, !"Debug Info Version", i32 3}
+!9 = !{i32 1, !"PIC Level", i32 2}
+!10 = !{!"clang version 5.0.0"}
+!11 = distinct !DISubprogram(name: "main", scope: !3, file: !3, line: 4, type: !12, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: false, unit: !2, variables: !4)
+!12 = !DISubroutineType(types: !13)
+!13 = !{!6}
+!14 = !DILocation(line: 7, column: 4, scope: !11)
+!15 = !DILocalVariable(name: "a", scope: !11, file: !3, line: 5, type: !6)
+!16 = !DIExpression()
+!17 = !DILocation(line: 5, column: 6, scope: !11)
+!18 = !DILocalVariable(name: "b", scope: !11, file: !3, line: 5, type: !6)
+!19 = !DILocation(line: 5, column: 9, scope: !11)
+!20 = !DILocalVariable(name: "c", scope: !11, file: !3, line: 5, type: !6)
+!21 = !DILocation(line: 5, column: 12, scope: !11)
+!22 = !DILocalVariable(name: "d", scope: !11, file: !3, line: 5, type: !6)
+!23 = !DILocation(line: 5, column: 15, scope: !11)
+!24 = !DILocation(line: 14, column: 4, scope: !11)
+!25 = !DILocation(line: 21, column: 2, scope: !11)
Added: llvm/trunk/test/CodeGen/X86/machine-outliner.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/machine-outliner.ll?rev=297081&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/machine-outliner.ll (added)
+++ llvm/trunk/test/CodeGen/X86/machine-outliner.ll Mon Mar 6 15:31:18 2017
@@ -0,0 +1,110 @@
+; RUN: llc -enable-machine-outliner -mtriple=x86_64-apple-darwin < %s | FileCheck %s
+
+ at x = global i32 0, align 4
+
+define i32 @check_boundaries() #0 {
+ ; CHECK-LABEL: _check_boundaries:
+ %1 = alloca i32, align 4
+ %2 = alloca i32, align 4
+ %3 = alloca i32, align 4
+ %4 = alloca i32, align 4
+ %5 = alloca i32, align 4
+ store i32 0, i32* %1, align 4
+ store i32 0, i32* %2, align 4
+ %6 = load i32, i32* %2, align 4
+ %7 = icmp ne i32 %6, 0
+ br i1 %7, label %9, label %8
+
+ ; CHECK: callq l_OUTLINED_FUNCTION_1
+ ; CHECK: cmpl $0, -{{[0-9]+}}(%rbp)
+ store i32 1, i32* %2, align 4
+ store i32 2, i32* %3, align 4
+ store i32 3, i32* %4, align 4
+ store i32 4, i32* %5, align 4
+ br label %10
+
+ store i32 1, i32* %4, align 4
+ br label %10
+
+ %11 = load i32, i32* %2, align 4
+ %12 = icmp ne i32 %11, 0
+ br i1 %12, label %14, label %13
+
+ ; CHECK: callq l_OUTLINED_FUNCTION_1
+ store i32 1, i32* %2, align 4
+ store i32 2, i32* %3, align 4
+ store i32 3, i32* %4, align 4
+ store i32 4, i32* %5, align 4
+ br label %15
+
+ store i32 1, i32* %4, align 4
+ br label %15
+
+ ret i32 0
+}
+
+define i32 @empty_1() #0 {
+ ; CHECK-LABEL: _empty_1:
+ ; CHECK-NOT: callq l_OUTLINED_FUNCTION_{{[0-9]+}}
+ ret i32 1
+}
+
+define i32 @empty_2() #0 {
+ ; CHECK-LABEL: _empty_2
+ ; CHECK-NOT: callq l_OUTLINED_FUNCTION_{{[0-9]+}}
+ ret i32 1
+}
+
+define i32 @no_empty_outlining() #0 {
+ ; CHECK-LABEL: _no_empty_outlining:
+ %1 = alloca i32, align 4
+ store i32 0, i32* %1, align 4
+ ; CHECK-NOT: callq l_OUTLINED_FUNCTION_{{[0-9]+}}
+ %2 = call i32 @empty_1() #1
+ %3 = call i32 @empty_2() #1
+ %4 = call i32 @empty_1() #1
+ %5 = call i32 @empty_2() #1
+ %6 = call i32 @empty_1() #1
+ %7 = call i32 @empty_2() #1
+ ret i32 0
+}
+
+define i32 @main() #0 {
+ ; CHECK-LABEL: _main:
+ %1 = alloca i32, align 4
+ %2 = alloca i32, align 4
+ %3 = alloca i32, align 4
+ %4 = alloca i32, align 4
+ %5 = alloca i32, align 4
+
+ store i32 0, i32* %1, align 4
+ store i32 0, i32* @x, align 4
+ ; CHECK: callq l_OUTLINED_FUNCTION_0
+ store i32 1, i32* %2, align 4
+ store i32 2, i32* %3, align 4
+ store i32 3, i32* %4, align 4
+ store i32 4, i32* %5, align 4
+ store i32 1, i32* @x, align 4
+ ; CHECK: callq l_OUTLINED_FUNCTION_0
+ store i32 1, i32* %2, align 4
+ store i32 2, i32* %3, align 4
+ store i32 3, i32* %4, align 4
+ store i32 4, i32* %5, align 4
+ ret i32 0
+}
+
+attributes #0 = { noredzone nounwind ssp uwtable "no-frame-pointer-elim"="true" }
+
+; CHECK-LABEL: l_OUTLINED_FUNCTION_0:
+; CHECK: movl $1, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $2, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $3, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $4, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: retq
+
+; CHECK-LABEL: l_OUTLINED_FUNCTION_1:
+; CHECK: movl $1, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $2, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $3, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: movl $4, -{{[0-9]+}}(%rbp)
+; CHECK-NEXT: retq
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