[cfe-commits] r49591 - in /cfe/trunk: clang.xcodeproj/project.pbxproj include/clang/Rewrite/DeltaTree.h lib/Rewrite/DeltaTree.cpp
Chris Lattner
sabre at nondot.org
Sat Apr 12 15:00:40 PDT 2008
Author: lattner
Date: Sat Apr 12 17:00:40 2008
New Revision: 49591
URL: http://llvm.org/viewvc/llvm-project?rev=49591&view=rev
Log:
move the DeltaTree implementation out of line, remove debugging printfs etc.
Added:
cfe/trunk/lib/Rewrite/DeltaTree.cpp
Modified:
cfe/trunk/clang.xcodeproj/project.pbxproj
cfe/trunk/include/clang/Rewrite/DeltaTree.h
Modified: cfe/trunk/clang.xcodeproj/project.pbxproj
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/clang.xcodeproj/project.pbxproj?rev=49591&r1=49590&r2=49591&view=diff
==============================================================================
--- cfe/trunk/clang.xcodeproj/project.pbxproj (original)
+++ cfe/trunk/clang.xcodeproj/project.pbxproj Sat Apr 12 17:00:40 2008
@@ -171,6 +171,7 @@
DEF2F0100C6CFED5000C4259 /* SemaChecking.cpp in Sources */ = {isa = PBXBuildFile; fileRef = DEF2F00F0C6CFED5000C4259 /* SemaChecking.cpp */; };
DEF7D9F70C9C8B1A0001F598 /* Rewriter.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = DEF7D9F60C9C8B1A0001F598 /* Rewriter.h */; };
DEF7D9F90C9C8B1D0001F598 /* Rewriter.cpp in Sources */ = {isa = PBXBuildFile; fileRef = DEF7D9F80C9C8B1D0001F598 /* Rewriter.cpp */; };
+ DEFFECA70DB1546600B4E7C3 /* DeltaTree.cpp in Sources */ = {isa = PBXBuildFile; fileRef = DEFFECA60DB1546600B4E7C3 /* DeltaTree.cpp */; };
F0226FD20C18084500141F42 /* TextDiagnosticPrinter.cpp in Sources */ = {isa = PBXBuildFile; fileRef = F0226FD00C18084500141F42 /* TextDiagnosticPrinter.cpp */; };
F0226FD30C18084500141F42 /* TextDiagnosticPrinter.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = F0226FD10C18084500141F42 /* TextDiagnosticPrinter.h */; };
/* End PBXBuildFile section */
@@ -458,6 +459,7 @@
DEF7D9F60C9C8B1A0001F598 /* Rewriter.h */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.c.h; name = Rewriter.h; path = clang/Rewrite/Rewriter.h; sourceTree = "<group>"; };
DEF7D9F80C9C8B1D0001F598 /* Rewriter.cpp */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.cpp.cpp; name = Rewriter.cpp; path = lib/Rewrite/Rewriter.cpp; sourceTree = "<group>"; };
DEFFECA30DB093D100B4E7C3 /* DeltaTree.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = DeltaTree.h; path = clang/Rewrite/DeltaTree.h; sourceTree = "<group>"; };
+ DEFFECA60DB1546600B4E7C3 /* DeltaTree.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = DeltaTree.cpp; path = lib/Rewrite/DeltaTree.cpp; sourceTree = "<group>"; };
F0226FD00C18084500141F42 /* TextDiagnosticPrinter.cpp */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.cpp.cpp; name = TextDiagnosticPrinter.cpp; path = Driver/TextDiagnosticPrinter.cpp; sourceTree = "<group>"; };
F0226FD10C18084500141F42 /* TextDiagnosticPrinter.h */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.c.h; name = TextDiagnosticPrinter.h; path = Driver/TextDiagnosticPrinter.h; sourceTree = "<group>"; };
/* End PBXFileReference section */
@@ -902,6 +904,7 @@
DEF7D9F50C9C8B0C0001F598 /* Rewrite */ = {
isa = PBXGroup;
children = (
+ DEFFECA60DB1546600B4E7C3 /* DeltaTree.cpp */,
72D16C1E0D9975C400E6DA4A /* HTMLRewrite.cpp */,
DEF7D9F80C9C8B1D0001F598 /* Rewriter.cpp */,
);
@@ -1061,6 +1064,7 @@
DECAB0950DA684C500E13CCB /* CGObjCEtoile.cpp in Sources */,
35EF67700DAD1D2C00B19414 /* SemaDeclCXX.cpp in Sources */,
352712510DAFE54700C76352 /* IdentifierResolver.cpp in Sources */,
+ DEFFECA70DB1546600B4E7C3 /* DeltaTree.cpp in Sources */,
);
runOnlyForDeploymentPostprocessing = 0;
};
Modified: cfe/trunk/include/clang/Rewrite/DeltaTree.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Rewrite/DeltaTree.h?rev=49591&r1=49590&r2=49591&view=diff
==============================================================================
--- cfe/trunk/include/clang/Rewrite/DeltaTree.h (original)
+++ cfe/trunk/include/clang/Rewrite/DeltaTree.h Sat Apr 12 17:00:40 2008
@@ -14,270 +14,8 @@
#ifndef CLANG_REWRITE_DELTATREE_H
#define CLANG_REWRITE_DELTATREE_H
-#include "llvm/Support/Casting.h"
-
namespace clang {
- using llvm::cast;
- using llvm::dyn_cast;
- class DeltaTreeInteriorNode;
-
- /// SourceDelta - As code in the original input buffer is added and deleted,
- /// SourceDelta records are used to keep track of how the input SourceLocation
- /// object is mapped into the output buffer.
- struct SourceDelta {
- unsigned FileLoc;
- int Delta;
-
- static SourceDelta get(unsigned Loc, int D) {
- SourceDelta Delta;
- Delta.FileLoc = Loc;
- Delta.Delta = D;
- return Delta;
- }
- };
-
- /// The DeltaTree class is a multiway search tree (BTree) structure with some
- /// fancy features. B-Trees are are generally more memory and cache efficient
- /// than binary trees, because they store multiple keys/values in each node.
- ///
- /// DeltaTree implements a key/value mapping from FileIndex to Delta, allowing
- /// fast lookup by FileIndex. However, an added (important) bonus is that it
- /// can also efficiently tell us the full accumulated delta for a specific
- /// file offset as well, without traversing the whole tree.
- ///
- /// The nodes of the tree are made up of instances of two classes:
- /// DeltaTreeNode and DeltaTreeInteriorNode. The later subclasses the
- /// former and adds children pointers. Each node knows the full delta of all
- /// entries (recursively) contained inside of it, which allows us to get the
- /// full delta implied by a whole subtree in constant time.
-
- /// DeltaTreeNode - The common part of all nodes.
- ///
- class DeltaTreeNode {
- friend class DeltaTreeInteriorNode;
-
- /// WidthFactor - This controls the number of K/V slots held in the BTree:
- /// how wide it is. Each level of the BTree is guaranteed to have at least
- /// WidthFactor-1 K/V pairs (unless the whole tree is less full than that)
- /// and may have at most 2*WidthFactor-1 K/V pairs.
- enum { WidthFactor = 8 };
-
- /// Values - This tracks the SourceDelta's currently in this node.
- ///
- SourceDelta Values[2*WidthFactor-1];
-
- /// NumValuesUsed - This tracks the number of values this node currently
- /// holds.
- unsigned char NumValuesUsed;
-
- /// IsLeaf - This is true if this is a leaf of the btree. If false, this is
- /// an interior node, and is actually an instance of DeltaTreeInteriorNode.
- bool IsLeaf;
-
- /// FullDelta - This is the full delta of all the values in this node and
- /// all children nodes.
- int FullDelta;
- public:
- DeltaTreeNode(bool isLeaf = true)
- : NumValuesUsed(0), IsLeaf(isLeaf), FullDelta(0) {}
-
- bool isLeaf() const { return IsLeaf; }
- int getFullDelta() const { return FullDelta; }
- bool isFull() const { return NumValuesUsed == 2*WidthFactor-1; }
-
- unsigned getNumValuesUsed() const { return NumValuesUsed; }
- const SourceDelta &getValue(unsigned i) const {
- assert(i < NumValuesUsed && "Invalid value #");
- return Values[i];
- }
- SourceDelta &getValue(unsigned i) {
- assert(i < NumValuesUsed && "Invalid value #");
- return Values[i];
- }
-
- /// AddDeltaNonFull - Add a delta to this tree and/or it's children, knowing
- /// that this node is not currently full.
- void AddDeltaNonFull(unsigned FileIndex, int Delta);
-
- /// RecomputeFullDeltaLocally - Recompute the FullDelta field by doing a
- /// local walk over our contained deltas.
- void RecomputeFullDeltaLocally();
-
- void Destroy();
-
- static inline bool classof(const DeltaTreeNode *) { return true; }
- };
-
- /// DeltaTreeInteriorNode - When isLeaf = false, a node has child pointers.
- /// This class tracks them.
- class DeltaTreeInteriorNode : public DeltaTreeNode {
- DeltaTreeNode *Children[2*WidthFactor];
- ~DeltaTreeInteriorNode() {
- for (unsigned i = 0, e = NumValuesUsed+1; i != e; ++i)
- Children[i]->Destroy();
- }
- friend class DeltaTreeNode;
- public:
- DeltaTreeInteriorNode() : DeltaTreeNode(false /*nonleaf*/) {}
-
- DeltaTreeInteriorNode(DeltaTreeNode *FirstChild)
- : DeltaTreeNode(false /*nonleaf*/) {
- FullDelta = FirstChild->FullDelta;
- Children[0] = FirstChild;
- }
-
- const DeltaTreeNode *getChild(unsigned i) const {
- assert(i < getNumValuesUsed()+1 && "Invalid child");
- return Children[i];
- }
- DeltaTreeNode *getChild(unsigned i) {
- assert(i < getNumValuesUsed()+1 && "Invalid child");
- return Children[i];
- }
-
- static inline bool classof(const DeltaTreeInteriorNode *) { return true; }
- static inline bool classof(const DeltaTreeNode *N) { return !N->isLeaf(); }
- private:
- void SplitChild(unsigned ChildNo);
- };
-
- /// Destroy - A 'virtual' destructor.
- inline void DeltaTreeNode::Destroy() {
- if (isLeaf())
- delete this;
- else
- delete cast<DeltaTreeInteriorNode>(this);
- }
-
- /// RecomputeFullDeltaLocally - Recompute the FullDelta field by doing a
- /// local walk over our contained deltas.
- inline void DeltaTreeNode::RecomputeFullDeltaLocally() {
- int NewFullDelta = 0;
- for (unsigned i = 0, e = getNumValuesUsed(); i != e; ++i)
- NewFullDelta += Values[i].Delta;
- if (DeltaTreeInteriorNode *IN = dyn_cast<DeltaTreeInteriorNode>(this))
- for (unsigned i = 0, e = getNumValuesUsed()+1; i != e; ++i)
- NewFullDelta += IN->getChild(i)->getFullDelta();
- FullDelta = NewFullDelta;
- }
-
-
- /// AddDeltaNonFull - Add a delta to this tree and/or it's children, knowing
- /// that this node is not currently full.
- inline void DeltaTreeNode::AddDeltaNonFull(unsigned FileIndex, int Delta) {
- assert(!isFull() && "AddDeltaNonFull on a full tree?");
-
- // Maintain full delta for this node.
- FullDelta += Delta;
-
- // Find the insertion point, the first delta whose index is >= FileIndex.
- unsigned i = 0, e = getNumValuesUsed();
- while (i != e && FileIndex > getValue(i).FileLoc)
- ++i;
-
- // If we found an a record for exactly this file index, just merge this
- // value into the preexisting record and finish early.
- if (i != e && getValue(i).FileLoc == FileIndex) {
- // NOTE: Delta could drop to zero here. This means that the next delta
- // entry is useless and could be removed. Supporting erases is
- // significantly more complex though, so we just leave an entry with
- // Delta=0 in the tree.
- Values[i].Delta += Delta;
- return;
- }
-
- if (DeltaTreeInteriorNode *IN = dyn_cast<DeltaTreeInteriorNode>(this)) {
- // Insertion into an interior node propagates the value down to a child.
- DeltaTreeNode *Child = IN->getChild(i);
-
- // If the child tree is full, split it, pulling an element up into our
- // node.
- if (Child->isFull()) {
- IN->SplitChild(i);
- SourceDelta &MedianVal = getValue(i);
-
- // If the median value we pulled up is exactly our insert position, add
- // the delta and return.
- if (MedianVal.FileLoc == FileIndex) {
- MedianVal.Delta += Delta;
- return;
- }
-
- // If the median value pulled up is less than our current search point,
- // include those deltas and search down the RHS now.
- if (MedianVal.FileLoc < FileIndex)
- Child = IN->getChild(i+1);
- }
-
- Child->AddDeltaNonFull(FileIndex, Delta);
- } else {
- // For an insertion into a non-full leaf node, just insert the value in
- // its sorted position. This requires moving later values over.
- if (i != e)
- memmove(&Values[i+1], &Values[i], sizeof(Values[0])*(e-i));
- Values[i] = SourceDelta::get(FileIndex, Delta);
- ++NumValuesUsed;
- }
- }
-
- /// SplitChild - At this point, we know that the current node is not full and
- /// that the specified child of this node is. Split the child in half at its
- /// median, propagating one value up into us. Child may be either an interior
- /// or leaf node.
- inline void DeltaTreeInteriorNode::SplitChild(unsigned ChildNo) {
- //printf("SplitChild: %p %d\n", (void*)this, ChildNo);
-
- DeltaTreeNode *Child = getChild(ChildNo);
- assert(!isFull() && Child->isFull() && "Inconsistent constraints");
-
- // Since the child is full, it contains 2*WidthFactor-1 values. We move
- // the first 'WidthFactor-1' values to the LHS child (which we leave in the
- // original child), propagate one value up into us, and move the last
- // 'WidthFactor-1' values into thew RHS child.
-
- // Create the new child node.
- DeltaTreeNode *NewNode;
- if (DeltaTreeInteriorNode *CIN = dyn_cast<DeltaTreeInteriorNode>(Child)) {
- // If the child is an interior node, also move over 'WidthFactor' grand
- // children into the new node.
- NewNode = new DeltaTreeInteriorNode();
- memcpy(&((DeltaTreeInteriorNode*)NewNode)->Children[0],
- &CIN->Children[WidthFactor],
- WidthFactor*sizeof(CIN->Children[0]));
- } else {
- // Just create the child node.
- NewNode = new DeltaTreeNode();
- }
-
- // Move over the last 'WidthFactor-1' values from Child to NewNode.
- memcpy(&NewNode->Values[0], &Child->Values[WidthFactor],
- (WidthFactor-1)*sizeof(Child->Values[0]));
-
- // Decrease the number of values in the two children.
- NewNode->NumValuesUsed = Child->NumValuesUsed = WidthFactor-1;
-
- // Recompute the two children's full delta. Our delta hasn't changed, but
- // their delta has.
- NewNode->RecomputeFullDeltaLocally();
- Child->RecomputeFullDeltaLocally();
-
- // Now that we have two nodes and a new element, insert the median value
- // into ourself by moving all the later values/children down, then inserting
- // the new one.
- if (getNumValuesUsed() != ChildNo)
- memmove(&Children[ChildNo+2], &Children[ChildNo+1],
- (getNumValuesUsed()-ChildNo)*sizeof(Children[0]));
- Children[ChildNo+1] = NewNode;
-
- if (getNumValuesUsed() != ChildNo)
- memmove(&Values[ChildNo+1], &Values[ChildNo],
- (getNumValuesUsed()-ChildNo)*sizeof(Values[0]));
- Values[ChildNo] = Child->Values[WidthFactor-1];
- ++NumValuesUsed;
- }
-
-
-
+
/// DeltaTree - a multiway search tree (BTree) structure with some fancy
/// features. B-Trees are are generally more memory and cache efficient than
/// binary trees, because they store multiple keys/values in each node. This
@@ -286,133 +24,25 @@
/// efficiently tell us the full accumulated delta for a specific file offset
/// as well, without traversing the whole tree.
class DeltaTree {
- DeltaTreeNode *Root;
+ void *Root; // "DeltaTreeNode *"
void operator=(const DeltaTree&); // DO NOT IMPLEMENT
public:
- DeltaTree() {
- Root = new DeltaTreeNode();
- }
- DeltaTree(const DeltaTree &RHS) {
- // Currently we only support copying when the RHS is empty.
- assert(RHS.empty() && "Can only copy empty tree");
- Root = new DeltaTreeNode();
- }
+ DeltaTree();
- ~DeltaTree() {
- Root->Destroy();
- }
-
- bool empty() const {
- return Root->getNumValuesUsed() == 0;
- }
+ // Note: Currently we only support copying when the RHS is empty.
+ DeltaTree(const DeltaTree &RHS);
+ ~DeltaTree();
/// getDeltaAt - Return the accumulated delta at the specified file offset.
/// This includes all insertions or delections that occurred *before* the
/// specified file index.
- int getDeltaAt(unsigned FileIndex) const {
- const DeltaTreeNode *Node = Root;
-
- int Result = 0;
-
- // Walk down the tree.
- while (1) {
- // For all nodes, include any local deltas before the specified file
- // index by summing them up directly. Keep track of how many were
- // included.
- unsigned NumValsGreater = 0;
- for (unsigned e = Node->getNumValuesUsed(); NumValsGreater != e;
- ++NumValsGreater) {
- const SourceDelta &Val = Node->getValue(NumValsGreater);
-
- if (Val.FileLoc >= FileIndex)
- break;
- Result += Val.Delta;
- }
-
- // If we have an interior node, include information about children and
- // recurse. Otherwise, if we have a leaf, we're done.
- const DeltaTreeInteriorNode *IN = dyn_cast<DeltaTreeInteriorNode>(Node);
- if (!IN) return Result;
-
- // Include any children to the left of the values we skipped, all of
- // their deltas should be included as well.
- for (unsigned i = 0; i != NumValsGreater; ++i)
- Result += IN->getChild(i)->getFullDelta();
-
- // If we found exactly the value we were looking for, break off the
- // search early. There is no need to search the RHS of the value for
- // partial results.
- if (NumValsGreater != Node->getNumValuesUsed() &&
- Node->getValue(NumValsGreater).FileLoc == FileIndex)
- return Result;
-
- // Otherwise, traverse down the tree. The selected subtree may be
- // partially included in the range.
- Node = IN->getChild(NumValsGreater);
- }
- // NOT REACHED.
- }
-
+ int getDeltaAt(unsigned FileIndex) const;
/// AddDelta - When a change is made that shifts around the text buffer,
/// this method is used to record that info. It inserts a delta of 'Delta'
/// into the current DeltaTree at offset FileIndex.
- void AddDelta(unsigned FileIndex, int Delta) {
- assert(Delta && "Adding a noop?");
- //printf("Add: %d %d\n", FileIndex, Delta);
- //if (FileIndex == 9251)
- //printf("Here\n");
-
- // If the root is full, create a new dummy (non-empty) interior node that
- // points to it, allowing the old root to be split.
- if (Root->isFull())
- Root = new DeltaTreeInteriorNode(Root);
-
- Root->AddDeltaNonFull(FileIndex, Delta);
-
- //VerifyTree(Root);
- }
-
- void VerifyTree(const DeltaTreeNode *N) const {
- const DeltaTreeInteriorNode *IN = dyn_cast<DeltaTreeInteriorNode>(N);
- if (IN == 0) {
- // Verify leaves, just ensure that FullDelta matches up and the elements
- // are in proper order.
- int FullDelta = 0;
- for (unsigned i = 0, e = N->getNumValuesUsed(); i != e; ++i) {
- if (i)
- assert(N->getValue(i-1).FileLoc < N->getValue(i).FileLoc);
- FullDelta += N->getValue(i).Delta;
- }
- assert(FullDelta == N->getFullDelta());
- return;
- }
-
- // Verify interior nodes: Ensure that FullDelta matches up and the
- // elements are in proper order and the children are in proper order.
- int FullDelta = 0;
- for (unsigned i = 0, e = IN->getNumValuesUsed(); i != e; ++i) {
- const SourceDelta &IVal = N->getValue(i);
- const DeltaTreeNode *IChild = IN->getChild(i);
- if (i)
- assert(IN->getValue(i-1).FileLoc < IVal.FileLoc);
- FullDelta += IVal.Delta;
- FullDelta += IChild->getFullDelta();
-
- // The largest value in child #i should be smaller than FileLoc.
- assert(IChild->getValue(IChild->getNumValuesUsed()-1).FileLoc <
- IVal.FileLoc);
-
- // The smallest value in child #i+1 should be larger than FileLoc.
- assert(IN->getChild(i+1)->getValue(0).FileLoc > IVal.FileLoc);
- VerifyTree(IChild);
- }
-
- FullDelta += IN->getChild(IN->getNumValuesUsed())->getFullDelta();
-
- assert(FullDelta == N->getFullDelta());
- }
+ void AddDelta(unsigned FileIndex, int Delta);
};
-} // end namespace llvm
+} // end namespace clang
#endif
Added: cfe/trunk/lib/Rewrite/DeltaTree.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Rewrite/DeltaTree.cpp?rev=49591&view=auto
==============================================================================
--- cfe/trunk/lib/Rewrite/DeltaTree.cpp (added)
+++ cfe/trunk/lib/Rewrite/DeltaTree.cpp Sat Apr 12 17:00:40 2008
@@ -0,0 +1,416 @@
+//===--- DeltaTree.cpp - B-Tree for Rewrite Delta tracking ----------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the DeltaTree and related classes.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Rewrite/DeltaTree.h"
+#include "llvm/Support/Casting.h"
+#include <cstring>
+using namespace clang;
+using llvm::cast;
+using llvm::dyn_cast;
+
+namespace {
+ struct SourceDelta;
+ class DeltaTreeNode;
+ class DeltaTreeInteriorNode;
+}
+
+/// The DeltaTree class is a multiway search tree (BTree) structure with some
+/// fancy features. B-Trees are are generally more memory and cache efficient
+/// than binary trees, because they store multiple keys/values in each node.
+///
+/// DeltaTree implements a key/value mapping from FileIndex to Delta, allowing
+/// fast lookup by FileIndex. However, an added (important) bonus is that it
+/// can also efficiently tell us the full accumulated delta for a specific
+/// file offset as well, without traversing the whole tree.
+///
+/// The nodes of the tree are made up of instances of two classes:
+/// DeltaTreeNode and DeltaTreeInteriorNode. The later subclasses the
+/// former and adds children pointers. Each node knows the full delta of all
+/// entries (recursively) contained inside of it, which allows us to get the
+/// full delta implied by a whole subtree in constant time.
+
+namespace {
+ /// SourceDelta - As code in the original input buffer is added and deleted,
+ /// SourceDelta records are used to keep track of how the input SourceLocation
+ /// object is mapped into the output buffer.
+ struct SourceDelta {
+ unsigned FileLoc;
+ int Delta;
+
+ static SourceDelta get(unsigned Loc, int D) {
+ SourceDelta Delta;
+ Delta.FileLoc = Loc;
+ Delta.Delta = D;
+ return Delta;
+ }
+ };
+} // end anonymous namespace
+
+namespace {
+ /// DeltaTreeNode - The common part of all nodes.
+ ///
+ class DeltaTreeNode {
+ friend class DeltaTreeInteriorNode;
+
+ /// WidthFactor - This controls the number of K/V slots held in the BTree:
+ /// how wide it is. Each level of the BTree is guaranteed to have at least
+ /// WidthFactor-1 K/V pairs (unless the whole tree is less full than that)
+ /// and may have at most 2*WidthFactor-1 K/V pairs.
+ enum { WidthFactor = 8 };
+
+ /// Values - This tracks the SourceDelta's currently in this node.
+ ///
+ SourceDelta Values[2*WidthFactor-1];
+
+ /// NumValuesUsed - This tracks the number of values this node currently
+ /// holds.
+ unsigned char NumValuesUsed;
+
+ /// IsLeaf - This is true if this is a leaf of the btree. If false, this is
+ /// an interior node, and is actually an instance of DeltaTreeInteriorNode.
+ bool IsLeaf;
+
+ /// FullDelta - This is the full delta of all the values in this node and
+ /// all children nodes.
+ int FullDelta;
+ public:
+ DeltaTreeNode(bool isLeaf = true)
+ : NumValuesUsed(0), IsLeaf(isLeaf), FullDelta(0) {}
+
+ bool isLeaf() const { return IsLeaf; }
+ int getFullDelta() const { return FullDelta; }
+ bool isFull() const { return NumValuesUsed == 2*WidthFactor-1; }
+
+ unsigned getNumValuesUsed() const { return NumValuesUsed; }
+ const SourceDelta &getValue(unsigned i) const {
+ assert(i < NumValuesUsed && "Invalid value #");
+ return Values[i];
+ }
+ SourceDelta &getValue(unsigned i) {
+ assert(i < NumValuesUsed && "Invalid value #");
+ return Values[i];
+ }
+
+ /// AddDeltaNonFull - Add a delta to this tree and/or it's children, knowing
+ /// that this node is not currently full.
+ void AddDeltaNonFull(unsigned FileIndex, int Delta);
+
+ /// RecomputeFullDeltaLocally - Recompute the FullDelta field by doing a
+ /// local walk over our contained deltas.
+ void RecomputeFullDeltaLocally();
+
+ void Destroy();
+
+ static inline bool classof(const DeltaTreeNode *) { return true; }
+ };
+} // end anonymous namespace
+
+namespace {
+ /// DeltaTreeInteriorNode - When isLeaf = false, a node has child pointers.
+ /// This class tracks them.
+ class DeltaTreeInteriorNode : public DeltaTreeNode {
+ DeltaTreeNode *Children[2*WidthFactor];
+ ~DeltaTreeInteriorNode() {
+ for (unsigned i = 0, e = NumValuesUsed+1; i != e; ++i)
+ Children[i]->Destroy();
+ }
+ friend class DeltaTreeNode;
+ public:
+ DeltaTreeInteriorNode() : DeltaTreeNode(false /*nonleaf*/) {}
+
+ DeltaTreeInteriorNode(DeltaTreeNode *FirstChild)
+ : DeltaTreeNode(false /*nonleaf*/) {
+ FullDelta = FirstChild->FullDelta;
+ Children[0] = FirstChild;
+ }
+
+ const DeltaTreeNode *getChild(unsigned i) const {
+ assert(i < getNumValuesUsed()+1 && "Invalid child");
+ return Children[i];
+ }
+ DeltaTreeNode *getChild(unsigned i) {
+ assert(i < getNumValuesUsed()+1 && "Invalid child");
+ return Children[i];
+ }
+
+ static inline bool classof(const DeltaTreeInteriorNode *) { return true; }
+ static inline bool classof(const DeltaTreeNode *N) { return !N->isLeaf(); }
+ private:
+ void SplitChild(unsigned ChildNo);
+ };
+}
+
+
+/// Destroy - A 'virtual' destructor.
+void DeltaTreeNode::Destroy() {
+ if (isLeaf())
+ delete this;
+ else
+ delete cast<DeltaTreeInteriorNode>(this);
+}
+
+/// RecomputeFullDeltaLocally - Recompute the FullDelta field by doing a
+/// local walk over our contained deltas.
+void DeltaTreeNode::RecomputeFullDeltaLocally() {
+ int NewFullDelta = 0;
+ for (unsigned i = 0, e = getNumValuesUsed(); i != e; ++i)
+ NewFullDelta += Values[i].Delta;
+ if (DeltaTreeInteriorNode *IN = dyn_cast<DeltaTreeInteriorNode>(this))
+ for (unsigned i = 0, e = getNumValuesUsed()+1; i != e; ++i)
+ NewFullDelta += IN->getChild(i)->getFullDelta();
+ FullDelta = NewFullDelta;
+}
+
+
+/// AddDeltaNonFull - Add a delta to this tree and/or it's children, knowing
+/// that this node is not currently full.
+void DeltaTreeNode::AddDeltaNonFull(unsigned FileIndex, int Delta) {
+ assert(!isFull() && "AddDeltaNonFull on a full tree?");
+
+ // Maintain full delta for this node.
+ FullDelta += Delta;
+
+ // Find the insertion point, the first delta whose index is >= FileIndex.
+ unsigned i = 0, e = getNumValuesUsed();
+ while (i != e && FileIndex > getValue(i).FileLoc)
+ ++i;
+
+ // If we found an a record for exactly this file index, just merge this
+ // value into the preexisting record and finish early.
+ if (i != e && getValue(i).FileLoc == FileIndex) {
+ // NOTE: Delta could drop to zero here. This means that the next delta
+ // entry is useless and could be removed. Supporting erases is
+ // significantly more complex though, so we just leave an entry with
+ // Delta=0 in the tree.
+ Values[i].Delta += Delta;
+ return;
+ }
+
+ if (DeltaTreeInteriorNode *IN = dyn_cast<DeltaTreeInteriorNode>(this)) {
+ // Insertion into an interior node propagates the value down to a child.
+ DeltaTreeNode *Child = IN->getChild(i);
+
+ // If the child tree is full, split it, pulling an element up into our
+ // node.
+ if (Child->isFull()) {
+ IN->SplitChild(i);
+ SourceDelta &MedianVal = getValue(i);
+
+ // If the median value we pulled up is exactly our insert position, add
+ // the delta and return.
+ if (MedianVal.FileLoc == FileIndex) {
+ MedianVal.Delta += Delta;
+ return;
+ }
+
+ // If the median value pulled up is less than our current search point,
+ // include those deltas and search down the RHS now.
+ if (MedianVal.FileLoc < FileIndex)
+ Child = IN->getChild(i+1);
+ }
+
+ Child->AddDeltaNonFull(FileIndex, Delta);
+ } else {
+ // For an insertion into a non-full leaf node, just insert the value in
+ // its sorted position. This requires moving later values over.
+ if (i != e)
+ memmove(&Values[i+1], &Values[i], sizeof(Values[0])*(e-i));
+ Values[i] = SourceDelta::get(FileIndex, Delta);
+ ++NumValuesUsed;
+ }
+}
+
+/// SplitChild - At this point, we know that the current node is not full and
+/// that the specified child of this node is. Split the child in half at its
+/// median, propagating one value up into us. Child may be either an interior
+/// or leaf node.
+void DeltaTreeInteriorNode::SplitChild(unsigned ChildNo) {
+ DeltaTreeNode *Child = getChild(ChildNo);
+ assert(!isFull() && Child->isFull() && "Inconsistent constraints");
+
+ // Since the child is full, it contains 2*WidthFactor-1 values. We move
+ // the first 'WidthFactor-1' values to the LHS child (which we leave in the
+ // original child), propagate one value up into us, and move the last
+ // 'WidthFactor-1' values into thew RHS child.
+
+ // Create the new child node.
+ DeltaTreeNode *NewNode;
+ if (DeltaTreeInteriorNode *CIN = dyn_cast<DeltaTreeInteriorNode>(Child)) {
+ // If the child is an interior node, also move over 'WidthFactor' grand
+ // children into the new node.
+ NewNode = new DeltaTreeInteriorNode();
+ memcpy(&((DeltaTreeInteriorNode*)NewNode)->Children[0],
+ &CIN->Children[WidthFactor],
+ WidthFactor*sizeof(CIN->Children[0]));
+ } else {
+ // Just create the child node.
+ NewNode = new DeltaTreeNode();
+ }
+
+ // Move over the last 'WidthFactor-1' values from Child to NewNode.
+ memcpy(&NewNode->Values[0], &Child->Values[WidthFactor],
+ (WidthFactor-1)*sizeof(Child->Values[0]));
+
+ // Decrease the number of values in the two children.
+ NewNode->NumValuesUsed = Child->NumValuesUsed = WidthFactor-1;
+
+ // Recompute the two children's full delta. Our delta hasn't changed, but
+ // their delta has.
+ NewNode->RecomputeFullDeltaLocally();
+ Child->RecomputeFullDeltaLocally();
+
+ // Now that we have two nodes and a new element, insert the median value
+ // into ourself by moving all the later values/children down, then inserting
+ // the new one.
+ if (getNumValuesUsed() != ChildNo)
+ memmove(&Children[ChildNo+2], &Children[ChildNo+1],
+ (getNumValuesUsed()-ChildNo)*sizeof(Children[0]));
+ Children[ChildNo+1] = NewNode;
+
+ if (getNumValuesUsed() != ChildNo)
+ memmove(&Values[ChildNo+1], &Values[ChildNo],
+ (getNumValuesUsed()-ChildNo)*sizeof(Values[0]));
+ Values[ChildNo] = Child->Values[WidthFactor-1];
+ ++NumValuesUsed;
+}
+
+
+//===----------------------------------------------------------------------===//
+// DeltaTree Implementation
+//===----------------------------------------------------------------------===//
+
+
+/// VerifyTree - Walk the btree performing assertions on various properties to
+/// verify consistency. This is useful for debugging new changes to the tree.
+static void VerifyTree(const DeltaTreeNode *N) {
+ const DeltaTreeInteriorNode *IN = dyn_cast<DeltaTreeInteriorNode>(N);
+ if (IN == 0) {
+ // Verify leaves, just ensure that FullDelta matches up and the elements
+ // are in proper order.
+ int FullDelta = 0;
+ for (unsigned i = 0, e = N->getNumValuesUsed(); i != e; ++i) {
+ if (i)
+ assert(N->getValue(i-1).FileLoc < N->getValue(i).FileLoc);
+ FullDelta += N->getValue(i).Delta;
+ }
+ assert(FullDelta == N->getFullDelta());
+ return;
+ }
+
+ // Verify interior nodes: Ensure that FullDelta matches up and the
+ // elements are in proper order and the children are in proper order.
+ int FullDelta = 0;
+ for (unsigned i = 0, e = IN->getNumValuesUsed(); i != e; ++i) {
+ const SourceDelta &IVal = N->getValue(i);
+ const DeltaTreeNode *IChild = IN->getChild(i);
+ if (i)
+ assert(IN->getValue(i-1).FileLoc < IVal.FileLoc);
+ FullDelta += IVal.Delta;
+ FullDelta += IChild->getFullDelta();
+
+ // The largest value in child #i should be smaller than FileLoc.
+ assert(IChild->getValue(IChild->getNumValuesUsed()-1).FileLoc <
+ IVal.FileLoc);
+
+ // The smallest value in child #i+1 should be larger than FileLoc.
+ assert(IN->getChild(i+1)->getValue(0).FileLoc > IVal.FileLoc);
+ VerifyTree(IChild);
+ }
+
+ FullDelta += IN->getChild(IN->getNumValuesUsed())->getFullDelta();
+
+ assert(FullDelta == N->getFullDelta());
+}
+
+static DeltaTreeNode *getRoot(void *Root) {
+ return (DeltaTreeNode*)Root;
+}
+
+DeltaTree::DeltaTree() {
+ Root = new DeltaTreeNode();
+}
+DeltaTree::DeltaTree(const DeltaTree &RHS) {
+ // Currently we only support copying when the RHS is empty.
+ assert(getRoot(RHS.Root)->getNumValuesUsed() == 0 &&
+ "Can only copy empty tree");
+ Root = new DeltaTreeNode();
+}
+
+DeltaTree::~DeltaTree() {
+ getRoot(Root)->Destroy();
+}
+
+/// getDeltaAt - Return the accumulated delta at the specified file offset.
+/// This includes all insertions or delections that occurred *before* the
+/// specified file index.
+int DeltaTree::getDeltaAt(unsigned FileIndex) const {
+ const DeltaTreeNode *Node = getRoot(Root);
+
+ int Result = 0;
+
+ // Walk down the tree.
+ while (1) {
+ // For all nodes, include any local deltas before the specified file
+ // index by summing them up directly. Keep track of how many were
+ // included.
+ unsigned NumValsGreater = 0;
+ for (unsigned e = Node->getNumValuesUsed(); NumValsGreater != e;
+ ++NumValsGreater) {
+ const SourceDelta &Val = Node->getValue(NumValsGreater);
+
+ if (Val.FileLoc >= FileIndex)
+ break;
+ Result += Val.Delta;
+ }
+
+ // If we have an interior node, include information about children and
+ // recurse. Otherwise, if we have a leaf, we're done.
+ const DeltaTreeInteriorNode *IN = dyn_cast<DeltaTreeInteriorNode>(Node);
+ if (!IN) return Result;
+
+ // Include any children to the left of the values we skipped, all of
+ // their deltas should be included as well.
+ for (unsigned i = 0; i != NumValsGreater; ++i)
+ Result += IN->getChild(i)->getFullDelta();
+
+ // If we found exactly the value we were looking for, break off the
+ // search early. There is no need to search the RHS of the value for
+ // partial results.
+ if (NumValsGreater != Node->getNumValuesUsed() &&
+ Node->getValue(NumValsGreater).FileLoc == FileIndex)
+ return Result;
+
+ // Otherwise, traverse down the tree. The selected subtree may be
+ // partially included in the range.
+ Node = IN->getChild(NumValsGreater);
+ }
+ // NOT REACHED.
+}
+
+
+/// AddDelta - When a change is made that shifts around the text buffer,
+/// this method is used to record that info. It inserts a delta of 'Delta'
+/// into the current DeltaTree at offset FileIndex.
+void DeltaTree::AddDelta(unsigned FileIndex, int Delta) {
+ assert(Delta && "Adding a noop?");
+
+ // If the root is full, create a new dummy (non-empty) interior node that
+ // points to it, allowing the old root to be split.
+ if (getRoot(Root)->isFull())
+ Root = new DeltaTreeInteriorNode(getRoot(Root));
+
+ getRoot(Root)->AddDeltaNonFull(FileIndex, Delta);
+
+ //VerifyTree(Root);
+}
+
More information about the cfe-commits
mailing list