875 lines
		
	
	
		
			30 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			875 lines
		
	
	
		
			30 KiB
		
	
	
	
		
			C++
		
	
	
	
//===--- RDFGraph.h -------------------------------------------------------===//
 | 
						|
//
 | 
						|
//                     The LLVM Compiler Infrastructure
 | 
						|
//
 | 
						|
// This file is distributed under the University of Illinois Open Source
 | 
						|
// License. See LICENSE.TXT for details.
 | 
						|
//
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
//
 | 
						|
// Target-independent, SSA-based data flow graph for register data flow (RDF)
 | 
						|
// for a non-SSA program representation (e.g. post-RA machine code).
 | 
						|
//
 | 
						|
//
 | 
						|
// *** Introduction
 | 
						|
//
 | 
						|
// The RDF graph is a collection of nodes, each of which denotes some element
 | 
						|
// of the program. There are two main types of such elements: code and refe-
 | 
						|
// rences. Conceptually, "code" is something that represents the structure
 | 
						|
// of the program, e.g. basic block or a statement, while "reference" is an
 | 
						|
// instance of accessing a register, e.g. a definition or a use. Nodes are
 | 
						|
// connected with each other based on the structure of the program (such as
 | 
						|
// blocks, instructions, etc.), and based on the data flow (e.g. reaching
 | 
						|
// definitions, reached uses, etc.). The single-reaching-definition principle
 | 
						|
// of SSA is generally observed, although, due to the non-SSA representation
 | 
						|
// of the program, there are some differences between the graph and a "pure"
 | 
						|
// SSA representation.
 | 
						|
//
 | 
						|
//
 | 
						|
// *** Implementation remarks
 | 
						|
//
 | 
						|
// Since the graph can contain a large number of nodes, memory consumption
 | 
						|
// was one of the major design considerations. As a result, there is a single
 | 
						|
// base class NodeBase which defines all members used by all possible derived
 | 
						|
// classes. The members are arranged in a union, and a derived class cannot
 | 
						|
// add any data members of its own. Each derived class only defines the
 | 
						|
// functional interface, i.e. member functions. NodeBase must be a POD,
 | 
						|
// which implies that all of its members must also be PODs.
 | 
						|
// Since nodes need to be connected with other nodes, pointers have been
 | 
						|
// replaced with 32-bit identifiers: each node has an id of type NodeId.
 | 
						|
// There are mapping functions in the graph that translate between actual
 | 
						|
// memory addresses and the corresponding identifiers.
 | 
						|
// A node id of 0 is equivalent to nullptr.
 | 
						|
//
 | 
						|
//
 | 
						|
// *** Structure of the graph
 | 
						|
//
 | 
						|
// A code node is always a collection of other nodes. For example, a code
 | 
						|
// node corresponding to a basic block will contain code nodes corresponding
 | 
						|
// to instructions. In turn, a code node corresponding to an instruction will
 | 
						|
// contain a list of reference nodes that correspond to the definitions and
 | 
						|
// uses of registers in that instruction. The members are arranged into a
 | 
						|
// circular list, which is yet another consequence of the effort to save
 | 
						|
// memory: for each member node it should be possible to obtain its owner,
 | 
						|
// and it should be possible to access all other members. There are other
 | 
						|
// ways to accomplish that, but the circular list seemed the most natural.
 | 
						|
//
 | 
						|
// +- CodeNode -+
 | 
						|
// |            | <---------------------------------------------------+
 | 
						|
// +-+--------+-+                                                     |
 | 
						|
//   |FirstM  |LastM                                                  |
 | 
						|
//   |        +-------------------------------------+                 |
 | 
						|
//   |                                              |                 |
 | 
						|
//   V                                              V                 |
 | 
						|
//  +----------+ Next +----------+ Next       Next +----------+ Next  |
 | 
						|
//  |          |----->|          |-----> ... ----->|          |----->-+
 | 
						|
//  +- Member -+      +- Member -+                 +- Member -+
 | 
						|
//
 | 
						|
// The order of members is such that related reference nodes (see below)
 | 
						|
// should be contiguous on the member list.
 | 
						|
//
 | 
						|
// A reference node is a node that encapsulates an access to a register,
 | 
						|
// in other words, data flowing into or out of a register. There are two
 | 
						|
// major kinds of reference nodes: defs and uses. A def node will contain
 | 
						|
// the id of the first reached use, and the id of the first reached def.
 | 
						|
// Each def and use will contain the id of the reaching def, and also the
 | 
						|
// id of the next reached def (for def nodes) or use (for use nodes).
 | 
						|
// The "next node sharing the same reaching def" is denoted as "sibling".
 | 
						|
// In summary:
 | 
						|
// - Def node contains: reaching def, sibling, first reached def, and first
 | 
						|
// reached use.
 | 
						|
// - Use node contains: reaching def and sibling.
 | 
						|
//
 | 
						|
// +-- DefNode --+
 | 
						|
// | R2 = ...    | <---+--------------------+
 | 
						|
// ++---------+--+     |                    |
 | 
						|
//  |Reached  |Reached |                    |
 | 
						|
//  |Def      |Use     |                    |
 | 
						|
//  |         |        |Reaching            |Reaching
 | 
						|
//  |         V        |Def                 |Def
 | 
						|
//  |      +-- UseNode --+ Sib  +-- UseNode --+ Sib       Sib
 | 
						|
//  |      | ... = R2    |----->| ... = R2    |----> ... ----> 0
 | 
						|
//  |      +-------------+      +-------------+
 | 
						|
//  V
 | 
						|
// +-- DefNode --+ Sib
 | 
						|
// | R2 = ...    |----> ...
 | 
						|
// ++---------+--+
 | 
						|
//  |         |
 | 
						|
//  |         |
 | 
						|
// ...       ...
 | 
						|
//
 | 
						|
// To get a full picture, the circular lists connecting blocks within a
 | 
						|
// function, instructions within a block, etc. should be superimposed with
 | 
						|
// the def-def, def-use links shown above.
 | 
						|
// To illustrate this, consider a small example in a pseudo-assembly:
 | 
						|
// foo:
 | 
						|
//   add r2, r0, r1   ; r2 = r0+r1
 | 
						|
//   addi r0, r2, 1   ; r0 = r2+1
 | 
						|
//   ret r0           ; return value in r0
 | 
						|
//
 | 
						|
// The graph (in a format used by the debugging functions) would look like:
 | 
						|
//
 | 
						|
//   DFG dump:[
 | 
						|
//   f1: Function foo
 | 
						|
//   b2: === BB#0 === preds(0), succs(0):
 | 
						|
//   p3: phi [d4<r0>(,d12,u9):]
 | 
						|
//   p5: phi [d6<r1>(,,u10):]
 | 
						|
//   s7: add [d8<r2>(,,u13):, u9<r0>(d4):, u10<r1>(d6):]
 | 
						|
//   s11: addi [d12<r0>(d4,,u15):, u13<r2>(d8):]
 | 
						|
//   s14: ret [u15<r0>(d12):]
 | 
						|
//   ]
 | 
						|
//
 | 
						|
// The f1, b2, p3, etc. are node ids. The letter is prepended to indicate the
 | 
						|
// kind of the node (i.e. f - function, b - basic block, p - phi, s - state-
 | 
						|
// ment, d - def, u - use).
 | 
						|
// The format of a def node is:
 | 
						|
//   dN<R>(rd,d,u):sib,
 | 
						|
// where
 | 
						|
//   N   - numeric node id,
 | 
						|
//   R   - register being defined
 | 
						|
//   rd  - reaching def,
 | 
						|
//   d   - reached def,
 | 
						|
//   u   - reached use,
 | 
						|
//   sib - sibling.
 | 
						|
// The format of a use node is:
 | 
						|
//   uN<R>[!](rd):sib,
 | 
						|
// where
 | 
						|
//   N   - numeric node id,
 | 
						|
//   R   - register being used,
 | 
						|
//   rd  - reaching def,
 | 
						|
//   sib - sibling.
 | 
						|
// Possible annotations (usually preceding the node id):
 | 
						|
//   +   - preserving def,
 | 
						|
//   ~   - clobbering def,
 | 
						|
//   "   - shadow ref (follows the node id),
 | 
						|
//   !   - fixed register (appears after register name).
 | 
						|
//
 | 
						|
// The circular lists are not explicit in the dump.
 | 
						|
//
 | 
						|
//
 | 
						|
// *** Node attributes
 | 
						|
//
 | 
						|
// NodeBase has a member "Attrs", which is the primary way of determining
 | 
						|
// the node's characteristics. The fields in this member decide whether
 | 
						|
// the node is a code node or a reference node (i.e. node's "type"), then
 | 
						|
// within each type, the "kind" determines what specifically this node
 | 
						|
// represents. The remaining bits, "flags", contain additional information
 | 
						|
// that is even more detailed than the "kind".
 | 
						|
// CodeNode's kinds are:
 | 
						|
// - Phi:   Phi node, members are reference nodes.
 | 
						|
// - Stmt:  Statement, members are reference nodes.
 | 
						|
// - Block: Basic block, members are instruction nodes (i.e. Phi or Stmt).
 | 
						|
// - Func:  The whole function. The members are basic block nodes.
 | 
						|
// RefNode's kinds are:
 | 
						|
// - Use.
 | 
						|
// - Def.
 | 
						|
//
 | 
						|
// Meaning of flags:
 | 
						|
// - Preserving: applies only to defs. A preserving def is one that can
 | 
						|
//   preserve some of the original bits among those that are included in
 | 
						|
//   the register associated with that def. For example, if R0 is a 32-bit
 | 
						|
//   register, but a def can only change the lower 16 bits, then it will
 | 
						|
//   be marked as preserving.
 | 
						|
// - Shadow: a reference that has duplicates holding additional reaching
 | 
						|
//   defs (see more below).
 | 
						|
// - Clobbering: applied only to defs, indicates that the value generated
 | 
						|
//   by this def is unspecified. A typical example would be volatile registers
 | 
						|
//   after function calls.
 | 
						|
//
 | 
						|
//
 | 
						|
// *** Shadow references
 | 
						|
//
 | 
						|
// It may happen that a super-register can have two (or more) non-overlapping
 | 
						|
// sub-registers. When both of these sub-registers are defined and followed
 | 
						|
// by a use of the super-register, the use of the super-register will not
 | 
						|
// have a unique reaching def: both defs of the sub-registers need to be
 | 
						|
// accounted for. In such cases, a duplicate use of the super-register is
 | 
						|
// added and it points to the extra reaching def. Both uses are marked with
 | 
						|
// a flag "shadow". Example:
 | 
						|
// Assume t0 is a super-register of r0 and r1, r0 and r1 do not overlap:
 | 
						|
//   set r0, 1        ; r0 = 1
 | 
						|
//   set r1, 1        ; r1 = 1
 | 
						|
//   addi t1, t0, 1   ; t1 = t0+1
 | 
						|
//
 | 
						|
// The DFG:
 | 
						|
//   s1: set [d2<r0>(,,u9):]
 | 
						|
//   s3: set [d4<r1>(,,u10):]
 | 
						|
//   s5: addi [d6<t1>(,,):, u7"<t0>(d2):, u8"<t0>(d4):]
 | 
						|
//
 | 
						|
// The statement s5 has two use nodes for t0: u7" and u9". The quotation
 | 
						|
// mark " indicates that the node is a shadow.
 | 
						|
//
 | 
						|
#ifndef RDF_GRAPH_H
 | 
						|
#define RDF_GRAPH_H
 | 
						|
 | 
						|
#include "llvm/Support/Allocator.h"
 | 
						|
#include "llvm/Support/Debug.h"
 | 
						|
#include "llvm/Support/raw_ostream.h"
 | 
						|
#include "llvm/Support/Timer.h"
 | 
						|
 | 
						|
#include <functional>
 | 
						|
#include <map>
 | 
						|
#include <set>
 | 
						|
#include <unordered_map>
 | 
						|
#include <vector>
 | 
						|
 | 
						|
namespace llvm {
 | 
						|
  class MachineBasicBlock;
 | 
						|
  class MachineFunction;
 | 
						|
  class MachineInstr;
 | 
						|
  class MachineOperand;
 | 
						|
  class MachineDominanceFrontier;
 | 
						|
  class MachineDominatorTree;
 | 
						|
  class TargetInstrInfo;
 | 
						|
  class TargetRegisterInfo;
 | 
						|
 | 
						|
namespace rdf {
 | 
						|
  typedef uint32_t NodeId;
 | 
						|
 | 
						|
  struct NodeAttrs {
 | 
						|
    enum : uint16_t {
 | 
						|
      None          = 0x0000,   // Nothing
 | 
						|
 | 
						|
      // Types: 2 bits
 | 
						|
      TypeMask      = 0x0003,
 | 
						|
      Code          = 0x0001,   // 01, Container
 | 
						|
      Ref           = 0x0002,   // 10, Reference
 | 
						|
 | 
						|
      // Kind: 3 bits
 | 
						|
      KindMask      = 0x0007 << 2,
 | 
						|
      Def           = 0x0001 << 2,  // 001
 | 
						|
      Use           = 0x0002 << 2,  // 010
 | 
						|
      Phi           = 0x0003 << 2,  // 011
 | 
						|
      Stmt          = 0x0004 << 2,  // 100
 | 
						|
      Block         = 0x0005 << 2,  // 101
 | 
						|
      Func          = 0x0006 << 2,  // 110
 | 
						|
 | 
						|
      // Flags: 5 bits for now
 | 
						|
      FlagMask      = 0x001F << 5,
 | 
						|
      Shadow        = 0x0001 << 5,  // 00001, Has extra reaching defs.
 | 
						|
      Clobbering    = 0x0002 << 5,  // 00010, Produces unspecified values.
 | 
						|
      PhiRef        = 0x0004 << 5,  // 00100, Member of PhiNode.
 | 
						|
      Preserving    = 0x0008 << 5,  // 01000, Def can keep original bits.
 | 
						|
      Fixed         = 0x0010 << 5,  // 10000, Fixed register.
 | 
						|
    };
 | 
						|
 | 
						|
    static uint16_t type(uint16_t T)  { return T & TypeMask; }
 | 
						|
    static uint16_t kind(uint16_t T)  { return T & KindMask; }
 | 
						|
    static uint16_t flags(uint16_t T) { return T & FlagMask; }
 | 
						|
 | 
						|
    static uint16_t set_type(uint16_t A, uint16_t T) {
 | 
						|
      return (A & ~TypeMask) | T;
 | 
						|
    }
 | 
						|
    static uint16_t set_kind(uint16_t A, uint16_t K) {
 | 
						|
      return (A & ~KindMask) | K;
 | 
						|
    }
 | 
						|
    static uint16_t set_flags(uint16_t A, uint16_t F) {
 | 
						|
      return (A & ~FlagMask) | F;
 | 
						|
    }
 | 
						|
 | 
						|
    // Test if A contains B.
 | 
						|
    static bool contains(uint16_t A, uint16_t B) {
 | 
						|
      if (type(A) != Code)
 | 
						|
        return false;
 | 
						|
      uint16_t KB = kind(B);
 | 
						|
      switch (kind(A)) {
 | 
						|
        case Func:
 | 
						|
          return KB == Block;
 | 
						|
        case Block:
 | 
						|
          return KB == Phi || KB == Stmt;
 | 
						|
        case Phi:
 | 
						|
        case Stmt:
 | 
						|
          return type(B) == Ref;
 | 
						|
      }
 | 
						|
      return false;
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  struct BuildOptions {
 | 
						|
    enum : unsigned {
 | 
						|
      None          = 0x00,
 | 
						|
      KeepDeadPhis  = 0x01,   // Do not remove dead phis during build.
 | 
						|
    };
 | 
						|
  };
 | 
						|
 | 
						|
  template <typename T> struct NodeAddr {
 | 
						|
    NodeAddr() : Addr(nullptr), Id(0) {}
 | 
						|
    NodeAddr(T A, NodeId I) : Addr(A), Id(I) {}
 | 
						|
    NodeAddr(const NodeAddr&) = default;
 | 
						|
    NodeAddr &operator= (const NodeAddr&) = default;
 | 
						|
 | 
						|
    bool operator== (const NodeAddr<T> &NA) const {
 | 
						|
      assert((Addr == NA.Addr) == (Id == NA.Id));
 | 
						|
      return Addr == NA.Addr;
 | 
						|
    }
 | 
						|
    bool operator!= (const NodeAddr<T> &NA) const {
 | 
						|
      return !operator==(NA);
 | 
						|
    }
 | 
						|
    // Type cast (casting constructor). The reason for having this class
 | 
						|
    // instead of std::pair.
 | 
						|
    template <typename S> NodeAddr(const NodeAddr<S> &NA)
 | 
						|
      : Addr(static_cast<T>(NA.Addr)), Id(NA.Id) {}
 | 
						|
 | 
						|
    T Addr;
 | 
						|
    NodeId Id;
 | 
						|
  };
 | 
						|
 | 
						|
  struct NodeBase;
 | 
						|
 | 
						|
  // Fast memory allocation and translation between node id and node address.
 | 
						|
  // This is really the same idea as the one underlying the "bump pointer
 | 
						|
  // allocator", the difference being in the translation. A node id is
 | 
						|
  // composed of two components: the index of the block in which it was
 | 
						|
  // allocated, and the index within the block. With the default settings,
 | 
						|
  // where the number of nodes per block is 4096, the node id (minus 1) is:
 | 
						|
  //
 | 
						|
  // bit position:                11             0
 | 
						|
  // +----------------------------+--------------+
 | 
						|
  // | Index of the block         |Index in block|
 | 
						|
  // +----------------------------+--------------+
 | 
						|
  //
 | 
						|
  // The actual node id is the above plus 1, to avoid creating a node id of 0.
 | 
						|
  //
 | 
						|
  // This method significantly improved the build time, compared to using maps
 | 
						|
  // (std::unordered_map or DenseMap) to translate between pointers and ids.
 | 
						|
  struct NodeAllocator {
 | 
						|
    // Amount of storage for a single node.
 | 
						|
    enum { NodeMemSize = 32 };
 | 
						|
    NodeAllocator(uint32_t NPB = 4096)
 | 
						|
        : NodesPerBlock(NPB), BitsPerIndex(Log2_32(NPB)),
 | 
						|
          IndexMask((1 << BitsPerIndex)-1), ActiveEnd(nullptr) {
 | 
						|
      assert(isPowerOf2_32(NPB));
 | 
						|
    }
 | 
						|
    NodeBase *ptr(NodeId N) const {
 | 
						|
      uint32_t N1 = N-1;
 | 
						|
      uint32_t BlockN = N1 >> BitsPerIndex;
 | 
						|
      uint32_t Offset = (N1 & IndexMask) * NodeMemSize;
 | 
						|
      return reinterpret_cast<NodeBase*>(Blocks[BlockN]+Offset);
 | 
						|
    }
 | 
						|
    NodeId id(const NodeBase *P) const;
 | 
						|
    NodeAddr<NodeBase*> New();
 | 
						|
    void clear();
 | 
						|
 | 
						|
  private:
 | 
						|
    void startNewBlock();
 | 
						|
    bool needNewBlock();
 | 
						|
    uint32_t makeId(uint32_t Block, uint32_t Index) const {
 | 
						|
      // Add 1 to the id, to avoid the id of 0, which is treated as "null".
 | 
						|
      return ((Block << BitsPerIndex) | Index) + 1;
 | 
						|
    }
 | 
						|
 | 
						|
    const uint32_t NodesPerBlock;
 | 
						|
    const uint32_t BitsPerIndex;
 | 
						|
    const uint32_t IndexMask;
 | 
						|
    char *ActiveEnd;
 | 
						|
    std::vector<char*> Blocks;
 | 
						|
    typedef BumpPtrAllocatorImpl<MallocAllocator, 65536> AllocatorTy;
 | 
						|
    AllocatorTy MemPool;
 | 
						|
  };
 | 
						|
 | 
						|
  struct RegisterRef {
 | 
						|
    unsigned Reg, Sub;
 | 
						|
 | 
						|
    // No non-trivial constructors, since this will be a member of a union.
 | 
						|
    RegisterRef() = default;
 | 
						|
    RegisterRef(const RegisterRef &RR) = default;
 | 
						|
    RegisterRef &operator= (const RegisterRef &RR) = default;
 | 
						|
    bool operator== (const RegisterRef &RR) const {
 | 
						|
      return Reg == RR.Reg && Sub == RR.Sub;
 | 
						|
    }
 | 
						|
    bool operator!= (const RegisterRef &RR) const {
 | 
						|
      return !operator==(RR);
 | 
						|
    }
 | 
						|
    bool operator< (const RegisterRef &RR) const {
 | 
						|
      return Reg < RR.Reg || (Reg == RR.Reg && Sub < RR.Sub);
 | 
						|
    }
 | 
						|
  };
 | 
						|
  typedef std::set<RegisterRef> RegisterSet;
 | 
						|
 | 
						|
  struct RegisterAliasInfo {
 | 
						|
    RegisterAliasInfo(const TargetRegisterInfo &tri) : TRI(tri) {}
 | 
						|
    virtual ~RegisterAliasInfo() {}
 | 
						|
 | 
						|
    virtual std::vector<RegisterRef> getAliasSet(RegisterRef RR) const;
 | 
						|
    virtual bool alias(RegisterRef RA, RegisterRef RB) const;
 | 
						|
    virtual bool covers(RegisterRef RA, RegisterRef RB) const;
 | 
						|
    virtual bool covers(const RegisterSet &RRs, RegisterRef RR) const;
 | 
						|
 | 
						|
    const TargetRegisterInfo &TRI;
 | 
						|
  };
 | 
						|
 | 
						|
  struct TargetOperandInfo {
 | 
						|
    TargetOperandInfo(const TargetInstrInfo &tii) : TII(tii) {}
 | 
						|
    virtual ~TargetOperandInfo() {}
 | 
						|
    virtual bool isPreserving(const MachineInstr &In, unsigned OpNum) const;
 | 
						|
    virtual bool isClobbering(const MachineInstr &In, unsigned OpNum) const;
 | 
						|
    virtual bool isFixedReg(const MachineInstr &In, unsigned OpNum) const;
 | 
						|
 | 
						|
    const TargetInstrInfo &TII;
 | 
						|
  };
 | 
						|
 | 
						|
 | 
						|
  struct DataFlowGraph;
 | 
						|
 | 
						|
  struct NodeBase {
 | 
						|
  public:
 | 
						|
    // Make sure this is a POD.
 | 
						|
    NodeBase() = default;
 | 
						|
    uint16_t getType()  const { return NodeAttrs::type(Attrs); }
 | 
						|
    uint16_t getKind()  const { return NodeAttrs::kind(Attrs); }
 | 
						|
    uint16_t getFlags() const { return NodeAttrs::flags(Attrs); }
 | 
						|
    NodeId   getNext()  const { return Next; }
 | 
						|
 | 
						|
    uint16_t getAttrs() const { return Attrs; }
 | 
						|
    void setAttrs(uint16_t A) { Attrs = A; }
 | 
						|
    void setFlags(uint16_t F) { setAttrs(NodeAttrs::set_flags(getAttrs(), F)); }
 | 
						|
 | 
						|
    // Insert node NA after "this" in the circular chain.
 | 
						|
    void append(NodeAddr<NodeBase*> NA);
 | 
						|
    // Initialize all members to 0.
 | 
						|
    void init() { memset(this, 0, sizeof *this); }
 | 
						|
    void setNext(NodeId N) { Next = N; }
 | 
						|
 | 
						|
  protected:
 | 
						|
    uint16_t Attrs;
 | 
						|
    uint16_t Reserved;
 | 
						|
    NodeId Next;                // Id of the next node in the circular chain.
 | 
						|
    // Definitions of nested types. Using anonymous nested structs would make
 | 
						|
    // this class definition clearer, but unnamed structs are not a part of
 | 
						|
    // the standard.
 | 
						|
    struct Def_struct  {
 | 
						|
      NodeId DD, DU;          // Ids of the first reached def and use.
 | 
						|
    };
 | 
						|
    struct PhiU_struct  {
 | 
						|
      NodeId PredB;           // Id of the predecessor block for a phi use.
 | 
						|
    };
 | 
						|
    struct Code_struct {
 | 
						|
      void *CP;               // Pointer to the actual code.
 | 
						|
      NodeId FirstM, LastM;   // Id of the first member and last.
 | 
						|
    };
 | 
						|
    struct Ref_struct {
 | 
						|
      NodeId RD, Sib;         // Ids of the reaching def and the sibling.
 | 
						|
      union {
 | 
						|
        Def_struct Def;
 | 
						|
        PhiU_struct PhiU;
 | 
						|
      };
 | 
						|
      union {
 | 
						|
        MachineOperand *Op;   // Non-phi refs point to a machine operand.
 | 
						|
        RegisterRef RR;       // Phi refs store register info directly.
 | 
						|
      };
 | 
						|
    };
 | 
						|
 | 
						|
    // The actual payload.
 | 
						|
    union {
 | 
						|
      Ref_struct Ref;
 | 
						|
      Code_struct Code;
 | 
						|
    };
 | 
						|
  };
 | 
						|
  // The allocator allocates chunks of 32 bytes for each node. The fact that
 | 
						|
  // each node takes 32 bytes in memory is used for fast translation between
 | 
						|
  // the node id and the node address.
 | 
						|
  static_assert(sizeof(NodeBase) <= NodeAllocator::NodeMemSize,
 | 
						|
        "NodeBase must be at most NodeAllocator::NodeMemSize bytes");
 | 
						|
 | 
						|
  typedef std::vector<NodeAddr<NodeBase*>> NodeList;
 | 
						|
  typedef std::set<NodeId> NodeSet;
 | 
						|
 | 
						|
  struct RefNode : public NodeBase {
 | 
						|
    RefNode() = default;
 | 
						|
    RegisterRef getRegRef() const;
 | 
						|
    MachineOperand &getOp() {
 | 
						|
      assert(!(getFlags() & NodeAttrs::PhiRef));
 | 
						|
      return *Ref.Op;
 | 
						|
    }
 | 
						|
    void setRegRef(RegisterRef RR);
 | 
						|
    void setRegRef(MachineOperand *Op);
 | 
						|
    NodeId getReachingDef() const {
 | 
						|
      return Ref.RD;
 | 
						|
    }
 | 
						|
    void setReachingDef(NodeId RD) {
 | 
						|
      Ref.RD = RD;
 | 
						|
    }
 | 
						|
    NodeId getSibling() const {
 | 
						|
      return Ref.Sib;
 | 
						|
    }
 | 
						|
    void setSibling(NodeId Sib) {
 | 
						|
      Ref.Sib = Sib;
 | 
						|
    }
 | 
						|
    bool isUse() const {
 | 
						|
      assert(getType() == NodeAttrs::Ref);
 | 
						|
      return getKind() == NodeAttrs::Use;
 | 
						|
    }
 | 
						|
    bool isDef() const {
 | 
						|
      assert(getType() == NodeAttrs::Ref);
 | 
						|
      return getKind() == NodeAttrs::Def;
 | 
						|
    }
 | 
						|
 | 
						|
    template <typename Predicate>
 | 
						|
    NodeAddr<RefNode*> getNextRef(RegisterRef RR, Predicate P, bool NextOnly,
 | 
						|
        const DataFlowGraph &G);
 | 
						|
    NodeAddr<NodeBase*> getOwner(const DataFlowGraph &G);
 | 
						|
  };
 | 
						|
 | 
						|
  struct DefNode : public RefNode {
 | 
						|
    NodeId getReachedDef() const {
 | 
						|
      return Ref.Def.DD;
 | 
						|
    }
 | 
						|
    void setReachedDef(NodeId D) {
 | 
						|
      Ref.Def.DD = D;
 | 
						|
    }
 | 
						|
    NodeId getReachedUse() const {
 | 
						|
      return Ref.Def.DU;
 | 
						|
    }
 | 
						|
    void setReachedUse(NodeId U) {
 | 
						|
      Ref.Def.DU = U;
 | 
						|
    }
 | 
						|
 | 
						|
    void linkToDef(NodeId Self, NodeAddr<DefNode*> DA);
 | 
						|
  };
 | 
						|
 | 
						|
  struct UseNode : public RefNode {
 | 
						|
    void linkToDef(NodeId Self, NodeAddr<DefNode*> DA);
 | 
						|
  };
 | 
						|
 | 
						|
  struct PhiUseNode : public UseNode {
 | 
						|
    NodeId getPredecessor() const {
 | 
						|
      assert(getFlags() & NodeAttrs::PhiRef);
 | 
						|
      return Ref.PhiU.PredB;
 | 
						|
    }
 | 
						|
    void setPredecessor(NodeId B) {
 | 
						|
      assert(getFlags() & NodeAttrs::PhiRef);
 | 
						|
      Ref.PhiU.PredB = B;
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  struct CodeNode : public NodeBase {
 | 
						|
    template <typename T> T getCode() const {
 | 
						|
      return static_cast<T>(Code.CP);
 | 
						|
    }
 | 
						|
    void setCode(void *C) {
 | 
						|
      Code.CP = C;
 | 
						|
    }
 | 
						|
 | 
						|
    NodeAddr<NodeBase*> getFirstMember(const DataFlowGraph &G) const;
 | 
						|
    NodeAddr<NodeBase*> getLastMember(const DataFlowGraph &G) const;
 | 
						|
    void addMember(NodeAddr<NodeBase*> NA, const DataFlowGraph &G);
 | 
						|
    void addMemberAfter(NodeAddr<NodeBase*> MA, NodeAddr<NodeBase*> NA,
 | 
						|
        const DataFlowGraph &G);
 | 
						|
    void removeMember(NodeAddr<NodeBase*> NA, const DataFlowGraph &G);
 | 
						|
 | 
						|
    NodeList members(const DataFlowGraph &G) const;
 | 
						|
    template <typename Predicate>
 | 
						|
    NodeList members_if(Predicate P, const DataFlowGraph &G) const;
 | 
						|
  };
 | 
						|
 | 
						|
  struct InstrNode : public CodeNode {
 | 
						|
    NodeAddr<NodeBase*> getOwner(const DataFlowGraph &G);
 | 
						|
  };
 | 
						|
 | 
						|
  struct PhiNode : public InstrNode {
 | 
						|
    MachineInstr *getCode() const {
 | 
						|
      return nullptr;
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  struct StmtNode : public InstrNode {
 | 
						|
    MachineInstr *getCode() const {
 | 
						|
      return CodeNode::getCode<MachineInstr*>();
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  struct BlockNode : public CodeNode {
 | 
						|
    MachineBasicBlock *getCode() const {
 | 
						|
      return CodeNode::getCode<MachineBasicBlock*>();
 | 
						|
    }
 | 
						|
    void addPhi(NodeAddr<PhiNode*> PA, const DataFlowGraph &G);
 | 
						|
  };
 | 
						|
 | 
						|
  struct FuncNode : public CodeNode {
 | 
						|
    MachineFunction *getCode() const {
 | 
						|
      return CodeNode::getCode<MachineFunction*>();
 | 
						|
    }
 | 
						|
    NodeAddr<BlockNode*> findBlock(const MachineBasicBlock *BB,
 | 
						|
        const DataFlowGraph &G) const;
 | 
						|
    NodeAddr<BlockNode*> getEntryBlock(const DataFlowGraph &G);
 | 
						|
  };
 | 
						|
 | 
						|
  struct DataFlowGraph {
 | 
						|
    DataFlowGraph(MachineFunction &mf, const TargetInstrInfo &tii,
 | 
						|
        const TargetRegisterInfo &tri, const MachineDominatorTree &mdt,
 | 
						|
        const MachineDominanceFrontier &mdf, const RegisterAliasInfo &rai,
 | 
						|
        const TargetOperandInfo &toi);
 | 
						|
 | 
						|
    NodeBase *ptr(NodeId N) const;
 | 
						|
    template <typename T> T ptr(NodeId N) const {
 | 
						|
      return static_cast<T>(ptr(N));
 | 
						|
    }
 | 
						|
    NodeId id(const NodeBase *P) const;
 | 
						|
 | 
						|
    template <typename T> NodeAddr<T> addr(NodeId N) const {
 | 
						|
      return { ptr<T>(N), N };
 | 
						|
    }
 | 
						|
 | 
						|
    NodeAddr<FuncNode*> getFunc() const {
 | 
						|
      return Func;
 | 
						|
    }
 | 
						|
    MachineFunction &getMF() const {
 | 
						|
      return MF;
 | 
						|
    }
 | 
						|
    const TargetInstrInfo &getTII() const {
 | 
						|
      return TII;
 | 
						|
    }
 | 
						|
    const TargetRegisterInfo &getTRI() const {
 | 
						|
      return TRI;
 | 
						|
    }
 | 
						|
    const MachineDominatorTree &getDT() const {
 | 
						|
      return MDT;
 | 
						|
    }
 | 
						|
    const MachineDominanceFrontier &getDF() const {
 | 
						|
      return MDF;
 | 
						|
    }
 | 
						|
    const RegisterAliasInfo &getRAI() const {
 | 
						|
      return RAI;
 | 
						|
    }
 | 
						|
 | 
						|
    struct DefStack {
 | 
						|
      DefStack() = default;
 | 
						|
      bool empty() const { return Stack.empty() || top() == bottom(); }
 | 
						|
    private:
 | 
						|
      typedef NodeAddr<DefNode*> value_type;
 | 
						|
      struct Iterator {
 | 
						|
        typedef DefStack::value_type value_type;
 | 
						|
        Iterator &up() { Pos = DS.nextUp(Pos); return *this; }
 | 
						|
        Iterator &down() { Pos = DS.nextDown(Pos); return *this; }
 | 
						|
        value_type operator*() const {
 | 
						|
          assert(Pos >= 1);
 | 
						|
          return DS.Stack[Pos-1];
 | 
						|
        }
 | 
						|
        const value_type *operator->() const {
 | 
						|
          assert(Pos >= 1);
 | 
						|
          return &DS.Stack[Pos-1];
 | 
						|
        }
 | 
						|
        bool operator==(const Iterator &It) const { return Pos == It.Pos; }
 | 
						|
        bool operator!=(const Iterator &It) const { return Pos != It.Pos; }
 | 
						|
      private:
 | 
						|
        Iterator(const DefStack &S, bool Top);
 | 
						|
        // Pos-1 is the index in the StorageType object that corresponds to
 | 
						|
        // the top of the DefStack.
 | 
						|
        const DefStack &DS;
 | 
						|
        unsigned Pos;
 | 
						|
        friend struct DefStack;
 | 
						|
      };
 | 
						|
    public:
 | 
						|
      typedef Iterator iterator;
 | 
						|
      iterator top() const { return Iterator(*this, true); }
 | 
						|
      iterator bottom() const { return Iterator(*this, false); }
 | 
						|
      unsigned size() const;
 | 
						|
 | 
						|
      void push(NodeAddr<DefNode*> DA) { Stack.push_back(DA); }
 | 
						|
      void pop();
 | 
						|
      void start_block(NodeId N);
 | 
						|
      void clear_block(NodeId N);
 | 
						|
    private:
 | 
						|
      friend struct Iterator;
 | 
						|
      typedef std::vector<value_type> StorageType;
 | 
						|
      bool isDelimiter(const StorageType::value_type &P, NodeId N = 0) const {
 | 
						|
        return (P.Addr == nullptr) && (N == 0 || P.Id == N);
 | 
						|
      }
 | 
						|
      unsigned nextUp(unsigned P) const;
 | 
						|
      unsigned nextDown(unsigned P) const;
 | 
						|
      StorageType Stack;
 | 
						|
    };
 | 
						|
 | 
						|
    struct RegisterRefHasher {
 | 
						|
      unsigned operator() (RegisterRef RR) const {
 | 
						|
        return RR.Reg | (RR.Sub << 24);
 | 
						|
      }
 | 
						|
    };
 | 
						|
    // Make this std::unordered_map for speed of accessing elements.
 | 
						|
    typedef std::unordered_map<RegisterRef,DefStack,RegisterRefHasher>
 | 
						|
          DefStackMap;
 | 
						|
 | 
						|
    void build(unsigned Options = BuildOptions::None);
 | 
						|
    void pushDefs(NodeAddr<InstrNode*> IA, DefStackMap &DM);
 | 
						|
    void markBlock(NodeId B, DefStackMap &DefM);
 | 
						|
    void releaseBlock(NodeId B, DefStackMap &DefM);
 | 
						|
 | 
						|
    NodeAddr<RefNode*> getNextRelated(NodeAddr<InstrNode*> IA,
 | 
						|
        NodeAddr<RefNode*> RA) const;
 | 
						|
    NodeAddr<RefNode*> getNextImp(NodeAddr<InstrNode*> IA,
 | 
						|
        NodeAddr<RefNode*> RA, bool Create);
 | 
						|
    NodeAddr<RefNode*> getNextImp(NodeAddr<InstrNode*> IA,
 | 
						|
        NodeAddr<RefNode*> RA) const;
 | 
						|
    NodeAddr<RefNode*> getNextShadow(NodeAddr<InstrNode*> IA,
 | 
						|
        NodeAddr<RefNode*> RA, bool Create);
 | 
						|
    NodeAddr<RefNode*> getNextShadow(NodeAddr<InstrNode*> IA,
 | 
						|
        NodeAddr<RefNode*> RA) const;
 | 
						|
 | 
						|
    NodeList getRelatedRefs(NodeAddr<InstrNode*> IA,
 | 
						|
        NodeAddr<RefNode*> RA) const;
 | 
						|
 | 
						|
    void unlinkUse(NodeAddr<UseNode*> UA, bool RemoveFromOwner) {
 | 
						|
      unlinkUseDF(UA);
 | 
						|
      if (RemoveFromOwner)
 | 
						|
        removeFromOwner(UA);
 | 
						|
    }
 | 
						|
    void unlinkDef(NodeAddr<DefNode*> DA, bool RemoveFromOwner) {
 | 
						|
      unlinkDefDF(DA);
 | 
						|
      if (RemoveFromOwner)
 | 
						|
        removeFromOwner(DA);
 | 
						|
    }
 | 
						|
 | 
						|
    // Some useful filters.
 | 
						|
    template <uint16_t Kind>
 | 
						|
    static bool IsRef(const NodeAddr<NodeBase*> BA) {
 | 
						|
      return BA.Addr->getType() == NodeAttrs::Ref &&
 | 
						|
             BA.Addr->getKind() == Kind;
 | 
						|
    }
 | 
						|
    template <uint16_t Kind>
 | 
						|
    static bool IsCode(const NodeAddr<NodeBase*> BA) {
 | 
						|
      return BA.Addr->getType() == NodeAttrs::Code &&
 | 
						|
             BA.Addr->getKind() == Kind;
 | 
						|
    }
 | 
						|
    static bool IsDef(const NodeAddr<NodeBase*> BA) {
 | 
						|
      return BA.Addr->getType() == NodeAttrs::Ref &&
 | 
						|
             BA.Addr->getKind() == NodeAttrs::Def;
 | 
						|
    }
 | 
						|
    static bool IsUse(const NodeAddr<NodeBase*> BA) {
 | 
						|
      return BA.Addr->getType() == NodeAttrs::Ref &&
 | 
						|
             BA.Addr->getKind() == NodeAttrs::Use;
 | 
						|
    }
 | 
						|
    static bool IsPhi(const NodeAddr<NodeBase*> BA) {
 | 
						|
      return BA.Addr->getType() == NodeAttrs::Code &&
 | 
						|
             BA.Addr->getKind() == NodeAttrs::Phi;
 | 
						|
    }
 | 
						|
 | 
						|
  private:
 | 
						|
    void reset();
 | 
						|
 | 
						|
    NodeAddr<NodeBase*> newNode(uint16_t Attrs);
 | 
						|
    NodeAddr<NodeBase*> cloneNode(const NodeAddr<NodeBase*> B);
 | 
						|
    NodeAddr<UseNode*> newUse(NodeAddr<InstrNode*> Owner,
 | 
						|
        MachineOperand &Op, uint16_t Flags = NodeAttrs::None);
 | 
						|
    NodeAddr<PhiUseNode*> newPhiUse(NodeAddr<PhiNode*> Owner,
 | 
						|
        RegisterRef RR, NodeAddr<BlockNode*> PredB,
 | 
						|
        uint16_t Flags = NodeAttrs::PhiRef);
 | 
						|
    NodeAddr<DefNode*> newDef(NodeAddr<InstrNode*> Owner,
 | 
						|
        MachineOperand &Op, uint16_t Flags = NodeAttrs::None);
 | 
						|
    NodeAddr<DefNode*> newDef(NodeAddr<InstrNode*> Owner,
 | 
						|
        RegisterRef RR, uint16_t Flags = NodeAttrs::PhiRef);
 | 
						|
    NodeAddr<PhiNode*> newPhi(NodeAddr<BlockNode*> Owner);
 | 
						|
    NodeAddr<StmtNode*> newStmt(NodeAddr<BlockNode*> Owner,
 | 
						|
        MachineInstr *MI);
 | 
						|
    NodeAddr<BlockNode*> newBlock(NodeAddr<FuncNode*> Owner,
 | 
						|
        MachineBasicBlock *BB);
 | 
						|
    NodeAddr<FuncNode*> newFunc(MachineFunction *MF);
 | 
						|
 | 
						|
    template <typename Predicate>
 | 
						|
    std::pair<NodeAddr<RefNode*>,NodeAddr<RefNode*>>
 | 
						|
    locateNextRef(NodeAddr<InstrNode*> IA, NodeAddr<RefNode*> RA,
 | 
						|
        Predicate P) const;
 | 
						|
 | 
						|
    typedef std::map<NodeId,RegisterSet> BlockRefsMap;
 | 
						|
 | 
						|
    void buildStmt(NodeAddr<BlockNode*> BA, MachineInstr &In);
 | 
						|
    void buildBlockRefs(NodeAddr<BlockNode*> BA, BlockRefsMap &RefM);
 | 
						|
    void recordDefsForDF(BlockRefsMap &PhiM, BlockRefsMap &RefM,
 | 
						|
        NodeAddr<BlockNode*> BA);
 | 
						|
    void buildPhis(BlockRefsMap &PhiM, BlockRefsMap &RefM,
 | 
						|
        NodeAddr<BlockNode*> BA);
 | 
						|
    void removeUnusedPhis();
 | 
						|
 | 
						|
    template <typename T> void linkRefUp(NodeAddr<InstrNode*> IA,
 | 
						|
        NodeAddr<T> TA, DefStack &DS);
 | 
						|
    void linkStmtRefs(DefStackMap &DefM, NodeAddr<StmtNode*> SA);
 | 
						|
    void linkBlockRefs(DefStackMap &DefM, NodeAddr<BlockNode*> BA);
 | 
						|
 | 
						|
    void unlinkUseDF(NodeAddr<UseNode*> UA);
 | 
						|
    void unlinkDefDF(NodeAddr<DefNode*> DA);
 | 
						|
    void removeFromOwner(NodeAddr<RefNode*> RA) {
 | 
						|
      NodeAddr<InstrNode*> IA = RA.Addr->getOwner(*this);
 | 
						|
      IA.Addr->removeMember(RA, *this);
 | 
						|
    }
 | 
						|
 | 
						|
    NodeAddr<BlockNode*> findBlock(MachineBasicBlock *BB) {
 | 
						|
      return BlockNodes[BB];
 | 
						|
    }
 | 
						|
 | 
						|
    TimerGroup TimeG;
 | 
						|
    NodeAddr<FuncNode*> Func;
 | 
						|
    NodeAllocator Memory;
 | 
						|
    // Local map:  MachineBasicBlock -> NodeAddr<BlockNode*>
 | 
						|
    std::map<MachineBasicBlock*,NodeAddr<BlockNode*>> BlockNodes;
 | 
						|
 | 
						|
    MachineFunction &MF;
 | 
						|
    const TargetInstrInfo &TII;
 | 
						|
    const TargetRegisterInfo &TRI;
 | 
						|
    const MachineDominatorTree &MDT;
 | 
						|
    const MachineDominanceFrontier &MDF;
 | 
						|
    const RegisterAliasInfo &RAI;
 | 
						|
    const TargetOperandInfo &TOI;
 | 
						|
  };  // struct DataFlowGraph
 | 
						|
 | 
						|
  template <typename Predicate>
 | 
						|
  NodeAddr<RefNode*> RefNode::getNextRef(RegisterRef RR, Predicate P,
 | 
						|
        bool NextOnly, const DataFlowGraph &G) {
 | 
						|
    // Get the "Next" reference in the circular list that references RR and
 | 
						|
    // satisfies predicate "Pred".
 | 
						|
    auto NA = G.addr<NodeBase*>(getNext());
 | 
						|
 | 
						|
    while (NA.Addr != this) {
 | 
						|
      if (NA.Addr->getType() == NodeAttrs::Ref) {
 | 
						|
        NodeAddr<RefNode*> RA = NA;
 | 
						|
        if (RA.Addr->getRegRef() == RR && P(NA))
 | 
						|
          return NA;
 | 
						|
        if (NextOnly)
 | 
						|
          break;
 | 
						|
        NA = G.addr<NodeBase*>(NA.Addr->getNext());
 | 
						|
      } else {
 | 
						|
        // We've hit the beginning of the chain.
 | 
						|
        assert(NA.Addr->getType() == NodeAttrs::Code);
 | 
						|
        NodeAddr<CodeNode*> CA = NA;
 | 
						|
        NA = CA.Addr->getFirstMember(G);
 | 
						|
      }
 | 
						|
    }
 | 
						|
    // Return the equivalent of "nullptr" if such a node was not found.
 | 
						|
    return NodeAddr<RefNode*>();
 | 
						|
  }
 | 
						|
 | 
						|
  template <typename Predicate>
 | 
						|
  NodeList CodeNode::members_if(Predicate P, const DataFlowGraph &G) const {
 | 
						|
    NodeList MM;
 | 
						|
    auto M = getFirstMember(G);
 | 
						|
    if (M.Id == 0)
 | 
						|
      return MM;
 | 
						|
 | 
						|
    while (M.Addr != this) {
 | 
						|
      if (P(M))
 | 
						|
        MM.push_back(M);
 | 
						|
      M = G.addr<NodeBase*>(M.Addr->getNext());
 | 
						|
    }
 | 
						|
    return MM;
 | 
						|
  }
 | 
						|
 | 
						|
 | 
						|
  template <typename T> struct Print;
 | 
						|
  template <typename T>
 | 
						|
  raw_ostream &operator<< (raw_ostream &OS, const Print<T> &P);
 | 
						|
 | 
						|
  template <typename T>
 | 
						|
  struct Print {
 | 
						|
    Print(const T &x, const DataFlowGraph &g) : Obj(x), G(g) {}
 | 
						|
    const T &Obj;
 | 
						|
    const DataFlowGraph &G;
 | 
						|
  };
 | 
						|
 | 
						|
  template <typename T>
 | 
						|
  struct PrintNode : Print<NodeAddr<T>> {
 | 
						|
    PrintNode(const NodeAddr<T> &x, const DataFlowGraph &g)
 | 
						|
      : Print<NodeAddr<T>>(x, g) {}
 | 
						|
  };
 | 
						|
} // namespace rdf
 | 
						|
} // namespace llvm
 | 
						|
 | 
						|
#endif // RDF_GRAPH_H
 |