713 lines
17 KiB
C
Executable File
713 lines
17 KiB
C
Executable File
/* Ppmd7.c -- PPMdH codec
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2017-04-03 : Igor Pavlov : Public domain
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This code is based on PPMd var.H (2001): Dmitry Shkarin : Public domain */
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#include "Precomp.h"
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#include <string.h>
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#include "Ppmd7.h"
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const Byte PPMD7_kExpEscape[16] = { 25, 14, 9, 7, 5, 5, 4, 4, 4, 3, 3, 3, 2, 2, 2, 2 };
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static const UInt16 kInitBinEsc[] = { 0x3CDD, 0x1F3F, 0x59BF, 0x48F3, 0x64A1, 0x5ABC, 0x6632, 0x6051};
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#define MAX_FREQ 124
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#define UNIT_SIZE 12
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#define U2B(nu) ((UInt32)(nu) * UNIT_SIZE)
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#define U2I(nu) (p->Units2Indx[(size_t)(nu) - 1])
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#define I2U(indx) (p->Indx2Units[indx])
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#ifdef PPMD_32BIT
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#define REF(ptr) (ptr)
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#else
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#define REF(ptr) ((UInt32)((Byte *)(ptr) - (p)->Base))
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#endif
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#define STATS_REF(ptr) ((CPpmd_State_Ref)REF(ptr))
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#define CTX(ref) ((CPpmd7_Context *)Ppmd7_GetContext(p, ref))
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#define STATS(ctx) Ppmd7_GetStats(p, ctx)
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#define ONE_STATE(ctx) Ppmd7Context_OneState(ctx)
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#define SUFFIX(ctx) CTX((ctx)->Suffix)
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typedef CPpmd7_Context * CTX_PTR;
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struct CPpmd7_Node_;
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typedef
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#ifdef PPMD_32BIT
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struct CPpmd7_Node_ *
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#else
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UInt32
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#endif
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CPpmd7_Node_Ref;
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typedef struct CPpmd7_Node_
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{
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UInt16 Stamp; /* must be at offset 0 as CPpmd7_Context::NumStats. Stamp=0 means free */
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UInt16 NU;
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CPpmd7_Node_Ref Next; /* must be at offset >= 4 */
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CPpmd7_Node_Ref Prev;
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} CPpmd7_Node;
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#ifdef PPMD_32BIT
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#define NODE(ptr) (ptr)
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#else
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#define NODE(offs) ((CPpmd7_Node *)(p->Base + (offs)))
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#endif
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void Ppmd7_Construct(CPpmd7 *p)
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{
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unsigned i, k, m;
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p->Base = 0;
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for (i = 0, k = 0; i < PPMD_NUM_INDEXES; i++)
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{
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unsigned step = (i >= 12 ? 4 : (i >> 2) + 1);
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do { p->Units2Indx[k++] = (Byte)i; } while (--step);
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p->Indx2Units[i] = (Byte)k;
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}
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p->NS2BSIndx[0] = (0 << 1);
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p->NS2BSIndx[1] = (1 << 1);
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memset(p->NS2BSIndx + 2, (2 << 1), 9);
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memset(p->NS2BSIndx + 11, (3 << 1), 256 - 11);
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for (i = 0; i < 3; i++)
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p->NS2Indx[i] = (Byte)i;
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for (m = i, k = 1; i < 256; i++)
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{
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p->NS2Indx[i] = (Byte)m;
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if (--k == 0)
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k = (++m) - 2;
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}
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memset(p->HB2Flag, 0, 0x40);
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memset(p->HB2Flag + 0x40, 8, 0x100 - 0x40);
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}
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void Ppmd7_Free(CPpmd7 *p, ISzAllocPtr alloc)
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{
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ISzAlloc_Free(alloc, p->Base);
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p->Size = 0;
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p->Base = 0;
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}
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Bool Ppmd7_Alloc(CPpmd7 *p, UInt32 size, ISzAllocPtr alloc)
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{
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if (!p->Base || p->Size != size)
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{
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size_t size2;
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Ppmd7_Free(p, alloc);
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size2 = 0
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#ifndef PPMD_32BIT
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+ UNIT_SIZE
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#endif
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;
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p->AlignOffset =
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#ifdef PPMD_32BIT
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(4 - size) & 3;
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#else
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4 - (size & 3);
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#endif
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if ((p->Base = (Byte *)ISzAlloc_Alloc(alloc, p->AlignOffset + size + size2)) == 0)
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return False;
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p->Size = size;
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}
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return True;
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}
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static void InsertNode(CPpmd7 *p, void *node, unsigned indx)
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{
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*((CPpmd_Void_Ref *)node) = p->FreeList[indx];
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p->FreeList[indx] = REF(node);
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}
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static void *RemoveNode(CPpmd7 *p, unsigned indx)
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{
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CPpmd_Void_Ref *node = (CPpmd_Void_Ref *)Ppmd7_GetPtr(p, p->FreeList[indx]);
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p->FreeList[indx] = *node;
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return node;
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}
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static void SplitBlock(CPpmd7 *p, void *ptr, unsigned oldIndx, unsigned newIndx)
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{
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unsigned i, nu = I2U(oldIndx) - I2U(newIndx);
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ptr = (Byte *)ptr + U2B(I2U(newIndx));
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if (I2U(i = U2I(nu)) != nu)
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{
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unsigned k = I2U(--i);
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InsertNode(p, ((Byte *)ptr) + U2B(k), nu - k - 1);
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}
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InsertNode(p, ptr, i);
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}
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static void GlueFreeBlocks(CPpmd7 *p)
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{
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#ifdef PPMD_32BIT
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CPpmd7_Node headItem;
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CPpmd7_Node_Ref head = &headItem;
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#else
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CPpmd7_Node_Ref head = p->AlignOffset + p->Size;
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#endif
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CPpmd7_Node_Ref n = head;
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unsigned i;
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p->GlueCount = 255;
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/* create doubly-linked list of free blocks */
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for (i = 0; i < PPMD_NUM_INDEXES; i++)
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{
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UInt16 nu = I2U(i);
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CPpmd7_Node_Ref next = (CPpmd7_Node_Ref)p->FreeList[i];
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p->FreeList[i] = 0;
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while (next != 0)
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{
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CPpmd7_Node *node = NODE(next);
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node->Next = n;
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n = NODE(n)->Prev = next;
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next = *(const CPpmd7_Node_Ref *)node;
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node->Stamp = 0;
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node->NU = (UInt16)nu;
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}
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}
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NODE(head)->Stamp = 1;
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NODE(head)->Next = n;
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NODE(n)->Prev = head;
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if (p->LoUnit != p->HiUnit)
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((CPpmd7_Node *)p->LoUnit)->Stamp = 1;
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/* Glue free blocks */
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while (n != head)
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{
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CPpmd7_Node *node = NODE(n);
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UInt32 nu = (UInt32)node->NU;
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for (;;)
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{
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CPpmd7_Node *node2 = NODE(n) + nu;
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nu += node2->NU;
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if (node2->Stamp != 0 || nu >= 0x10000)
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break;
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NODE(node2->Prev)->Next = node2->Next;
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NODE(node2->Next)->Prev = node2->Prev;
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node->NU = (UInt16)nu;
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}
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n = node->Next;
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}
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/* Fill lists of free blocks */
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for (n = NODE(head)->Next; n != head;)
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{
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CPpmd7_Node *node = NODE(n);
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unsigned nu;
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CPpmd7_Node_Ref next = node->Next;
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for (nu = node->NU; nu > 128; nu -= 128, node += 128)
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InsertNode(p, node, PPMD_NUM_INDEXES - 1);
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if (I2U(i = U2I(nu)) != nu)
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{
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unsigned k = I2U(--i);
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InsertNode(p, node + k, nu - k - 1);
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}
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InsertNode(p, node, i);
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n = next;
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}
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}
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static void *AllocUnitsRare(CPpmd7 *p, unsigned indx)
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{
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unsigned i;
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void *retVal;
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if (p->GlueCount == 0)
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{
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GlueFreeBlocks(p);
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if (p->FreeList[indx] != 0)
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return RemoveNode(p, indx);
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}
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i = indx;
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do
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{
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if (++i == PPMD_NUM_INDEXES)
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{
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UInt32 numBytes = U2B(I2U(indx));
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p->GlueCount--;
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return ((UInt32)(p->UnitsStart - p->Text) > numBytes) ? (p->UnitsStart -= numBytes) : (NULL);
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}
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}
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while (p->FreeList[i] == 0);
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retVal = RemoveNode(p, i);
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SplitBlock(p, retVal, i, indx);
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return retVal;
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}
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static void *AllocUnits(CPpmd7 *p, unsigned indx)
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{
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UInt32 numBytes;
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if (p->FreeList[indx] != 0)
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return RemoveNode(p, indx);
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numBytes = U2B(I2U(indx));
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if (numBytes <= (UInt32)(p->HiUnit - p->LoUnit))
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{
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void *retVal = p->LoUnit;
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p->LoUnit += numBytes;
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return retVal;
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}
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return AllocUnitsRare(p, indx);
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}
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#define MyMem12Cpy(dest, src, num) \
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{ UInt32 *d = (UInt32 *)dest; const UInt32 *s = (const UInt32 *)src; UInt32 n = num; \
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do { d[0] = s[0]; d[1] = s[1]; d[2] = s[2]; s += 3; d += 3; } while (--n); }
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static void *ShrinkUnits(CPpmd7 *p, void *oldPtr, unsigned oldNU, unsigned newNU)
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{
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unsigned i0 = U2I(oldNU);
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unsigned i1 = U2I(newNU);
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if (i0 == i1)
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return oldPtr;
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if (p->FreeList[i1] != 0)
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{
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void *ptr = RemoveNode(p, i1);
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MyMem12Cpy(ptr, oldPtr, newNU);
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InsertNode(p, oldPtr, i0);
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return ptr;
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}
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SplitBlock(p, oldPtr, i0, i1);
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return oldPtr;
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}
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#define SUCCESSOR(p) ((CPpmd_Void_Ref)((p)->SuccessorLow | ((UInt32)(p)->SuccessorHigh << 16)))
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static void SetSuccessor(CPpmd_State *p, CPpmd_Void_Ref v)
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{
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(p)->SuccessorLow = (UInt16)((UInt32)(v) & 0xFFFF);
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(p)->SuccessorHigh = (UInt16)(((UInt32)(v) >> 16) & 0xFFFF);
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}
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static void RestartModel(CPpmd7 *p)
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{
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unsigned i, k, m;
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memset(p->FreeList, 0, sizeof(p->FreeList));
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p->Text = p->Base + p->AlignOffset;
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p->HiUnit = p->Text + p->Size;
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p->LoUnit = p->UnitsStart = p->HiUnit - p->Size / 8 / UNIT_SIZE * 7 * UNIT_SIZE;
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p->GlueCount = 0;
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p->OrderFall = p->MaxOrder;
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p->RunLength = p->InitRL = -(Int32)((p->MaxOrder < 12) ? p->MaxOrder : 12) - 1;
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p->PrevSuccess = 0;
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p->MinContext = p->MaxContext = (CTX_PTR)(p->HiUnit -= UNIT_SIZE); /* AllocContext(p); */
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p->MinContext->Suffix = 0;
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p->MinContext->NumStats = 256;
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p->MinContext->SummFreq = 256 + 1;
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p->FoundState = (CPpmd_State *)p->LoUnit; /* AllocUnits(p, PPMD_NUM_INDEXES - 1); */
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p->LoUnit += U2B(256 / 2);
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p->MinContext->Stats = REF(p->FoundState);
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for (i = 0; i < 256; i++)
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{
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CPpmd_State *s = &p->FoundState[i];
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s->Symbol = (Byte)i;
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s->Freq = 1;
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SetSuccessor(s, 0);
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}
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for (i = 0; i < 128; i++)
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for (k = 0; k < 8; k++)
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{
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UInt16 *dest = p->BinSumm[i] + k;
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UInt16 val = (UInt16)(PPMD_BIN_SCALE - kInitBinEsc[k] / (i + 2));
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for (m = 0; m < 64; m += 8)
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dest[m] = val;
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}
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for (i = 0; i < 25; i++)
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for (k = 0; k < 16; k++)
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{
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CPpmd_See *s = &p->See[i][k];
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s->Summ = (UInt16)((5 * i + 10) << (s->Shift = PPMD_PERIOD_BITS - 4));
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s->Count = 4;
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}
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}
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void Ppmd7_Init(CPpmd7 *p, unsigned maxOrder)
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{
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p->MaxOrder = maxOrder;
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RestartModel(p);
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p->DummySee.Shift = PPMD_PERIOD_BITS;
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p->DummySee.Summ = 0; /* unused */
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p->DummySee.Count = 64; /* unused */
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}
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static CTX_PTR CreateSuccessors(CPpmd7 *p, Bool skip)
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{
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CPpmd_State upState;
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CTX_PTR c = p->MinContext;
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CPpmd_Byte_Ref upBranch = (CPpmd_Byte_Ref)SUCCESSOR(p->FoundState);
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CPpmd_State *ps[PPMD7_MAX_ORDER];
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unsigned numPs = 0;
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if (!skip)
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ps[numPs++] = p->FoundState;
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while (c->Suffix)
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{
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CPpmd_Void_Ref successor;
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CPpmd_State *s;
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c = SUFFIX(c);
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if (c->NumStats != 1)
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{
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for (s = STATS(c); s->Symbol != p->FoundState->Symbol; s++);
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}
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else
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s = ONE_STATE(c);
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successor = SUCCESSOR(s);
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if (successor != upBranch)
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{
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c = CTX(successor);
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if (numPs == 0)
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return c;
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break;
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}
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ps[numPs++] = s;
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}
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upState.Symbol = *(const Byte *)Ppmd7_GetPtr(p, upBranch);
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SetSuccessor(&upState, upBranch + 1);
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if (c->NumStats == 1)
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upState.Freq = ONE_STATE(c)->Freq;
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else
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{
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UInt32 cf, s0;
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CPpmd_State *s;
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for (s = STATS(c); s->Symbol != upState.Symbol; s++);
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cf = s->Freq - 1;
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s0 = c->SummFreq - c->NumStats - cf;
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upState.Freq = (Byte)(1 + ((2 * cf <= s0) ? (5 * cf > s0) : ((2 * cf + 3 * s0 - 1) / (2 * s0))));
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}
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do
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{
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/* Create Child */
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CTX_PTR c1; /* = AllocContext(p); */
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if (p->HiUnit != p->LoUnit)
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c1 = (CTX_PTR)(p->HiUnit -= UNIT_SIZE);
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else if (p->FreeList[0] != 0)
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c1 = (CTX_PTR)RemoveNode(p, 0);
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else
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{
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c1 = (CTX_PTR)AllocUnitsRare(p, 0);
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if (!c1)
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return NULL;
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}
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c1->NumStats = 1;
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*ONE_STATE(c1) = upState;
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c1->Suffix = REF(c);
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SetSuccessor(ps[--numPs], REF(c1));
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c = c1;
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}
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while (numPs != 0);
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return c;
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}
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static void SwapStates(CPpmd_State *t1, CPpmd_State *t2)
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{
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CPpmd_State tmp = *t1;
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*t1 = *t2;
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*t2 = tmp;
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}
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static void UpdateModel(CPpmd7 *p)
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{
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CPpmd_Void_Ref successor, fSuccessor = SUCCESSOR(p->FoundState);
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CTX_PTR c;
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unsigned s0, ns;
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if (p->FoundState->Freq < MAX_FREQ / 4 && p->MinContext->Suffix != 0)
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{
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c = SUFFIX(p->MinContext);
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if (c->NumStats == 1)
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{
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CPpmd_State *s = ONE_STATE(c);
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if (s->Freq < 32)
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s->Freq++;
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}
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else
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{
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CPpmd_State *s = STATS(c);
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if (s->Symbol != p->FoundState->Symbol)
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{
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do { s++; } while (s->Symbol != p->FoundState->Symbol);
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if (s[0].Freq >= s[-1].Freq)
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{
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SwapStates(&s[0], &s[-1]);
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s--;
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}
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}
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if (s->Freq < MAX_FREQ - 9)
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{
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s->Freq += 2;
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c->SummFreq += 2;
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}
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}
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}
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if (p->OrderFall == 0)
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{
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p->MinContext = p->MaxContext = CreateSuccessors(p, True);
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if (p->MinContext == 0)
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{
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RestartModel(p);
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return;
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}
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SetSuccessor(p->FoundState, REF(p->MinContext));
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return;
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}
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*p->Text++ = p->FoundState->Symbol;
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successor = REF(p->Text);
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if (p->Text >= p->UnitsStart)
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{
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RestartModel(p);
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return;
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}
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if (fSuccessor)
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{
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if (fSuccessor <= successor)
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{
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CTX_PTR cs = CreateSuccessors(p, False);
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if (cs == NULL)
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{
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RestartModel(p);
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return;
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}
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fSuccessor = REF(cs);
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}
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if (--p->OrderFall == 0)
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{
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successor = fSuccessor;
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p->Text -= (p->MaxContext != p->MinContext);
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}
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}
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else
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{
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SetSuccessor(p->FoundState, successor);
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fSuccessor = REF(p->MinContext);
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|
}
|
|
|
|
s0 = p->MinContext->SummFreq - (ns = p->MinContext->NumStats) - (p->FoundState->Freq - 1);
|
|
|
|
for (c = p->MaxContext; c != p->MinContext; c = SUFFIX(c))
|
|
{
|
|
unsigned ns1;
|
|
UInt32 cf, sf;
|
|
if ((ns1 = c->NumStats) != 1)
|
|
{
|
|
if ((ns1 & 1) == 0)
|
|
{
|
|
/* Expand for one UNIT */
|
|
unsigned oldNU = ns1 >> 1;
|
|
unsigned i = U2I(oldNU);
|
|
if (i != U2I((size_t)oldNU + 1))
|
|
{
|
|
void *ptr = AllocUnits(p, i + 1);
|
|
void *oldPtr;
|
|
if (!ptr)
|
|
{
|
|
RestartModel(p);
|
|
return;
|
|
}
|
|
oldPtr = STATS(c);
|
|
MyMem12Cpy(ptr, oldPtr, oldNU);
|
|
InsertNode(p, oldPtr, i);
|
|
c->Stats = STATS_REF(ptr);
|
|
}
|
|
}
|
|
c->SummFreq = (UInt16)(c->SummFreq + (2 * ns1 < ns) + 2 * ((4 * ns1 <= ns) & (c->SummFreq <= 8 * ns1)));
|
|
}
|
|
else
|
|
{
|
|
CPpmd_State *s = (CPpmd_State*)AllocUnits(p, 0);
|
|
if (!s)
|
|
{
|
|
RestartModel(p);
|
|
return;
|
|
}
|
|
*s = *ONE_STATE(c);
|
|
c->Stats = REF(s);
|
|
if (s->Freq < MAX_FREQ / 4 - 1)
|
|
s->Freq <<= 1;
|
|
else
|
|
s->Freq = MAX_FREQ - 4;
|
|
c->SummFreq = (UInt16)(s->Freq + p->InitEsc + (ns > 3));
|
|
}
|
|
cf = 2 * (UInt32)p->FoundState->Freq * (c->SummFreq + 6);
|
|
sf = (UInt32)s0 + c->SummFreq;
|
|
if (cf < 6 * sf)
|
|
{
|
|
cf = 1 + (cf > sf) + (cf >= 4 * sf);
|
|
c->SummFreq += 3;
|
|
}
|
|
else
|
|
{
|
|
cf = 4 + (cf >= 9 * sf) + (cf >= 12 * sf) + (cf >= 15 * sf);
|
|
c->SummFreq = (UInt16)(c->SummFreq + cf);
|
|
}
|
|
{
|
|
CPpmd_State *s = STATS(c) + ns1;
|
|
SetSuccessor(s, successor);
|
|
s->Symbol = p->FoundState->Symbol;
|
|
s->Freq = (Byte)cf;
|
|
c->NumStats = (UInt16)(ns1 + 1);
|
|
}
|
|
}
|
|
p->MaxContext = p->MinContext = CTX(fSuccessor);
|
|
}
|
|
|
|
static void Rescale(CPpmd7 *p)
|
|
{
|
|
unsigned i, adder, sumFreq, escFreq;
|
|
CPpmd_State *stats = STATS(p->MinContext);
|
|
CPpmd_State *s = p->FoundState;
|
|
{
|
|
CPpmd_State tmp = *s;
|
|
for (; s != stats; s--)
|
|
s[0] = s[-1];
|
|
*s = tmp;
|
|
}
|
|
escFreq = p->MinContext->SummFreq - s->Freq;
|
|
s->Freq += 4;
|
|
adder = (p->OrderFall != 0);
|
|
s->Freq = (Byte)((s->Freq + adder) >> 1);
|
|
sumFreq = s->Freq;
|
|
|
|
i = p->MinContext->NumStats - 1;
|
|
do
|
|
{
|
|
escFreq -= (++s)->Freq;
|
|
s->Freq = (Byte)((s->Freq + adder) >> 1);
|
|
sumFreq += s->Freq;
|
|
if (s[0].Freq > s[-1].Freq)
|
|
{
|
|
CPpmd_State *s1 = s;
|
|
CPpmd_State tmp = *s1;
|
|
do
|
|
s1[0] = s1[-1];
|
|
while (--s1 != stats && tmp.Freq > s1[-1].Freq);
|
|
*s1 = tmp;
|
|
}
|
|
}
|
|
while (--i);
|
|
|
|
if (s->Freq == 0)
|
|
{
|
|
unsigned numStats = p->MinContext->NumStats;
|
|
unsigned n0, n1;
|
|
do { i++; } while ((--s)->Freq == 0);
|
|
escFreq += i;
|
|
p->MinContext->NumStats = (UInt16)(p->MinContext->NumStats - i);
|
|
if (p->MinContext->NumStats == 1)
|
|
{
|
|
CPpmd_State tmp = *stats;
|
|
do
|
|
{
|
|
tmp.Freq = (Byte)(tmp.Freq - (tmp.Freq >> 1));
|
|
escFreq >>= 1;
|
|
}
|
|
while (escFreq > 1);
|
|
InsertNode(p, stats, U2I(((numStats + 1) >> 1)));
|
|
*(p->FoundState = ONE_STATE(p->MinContext)) = tmp;
|
|
return;
|
|
}
|
|
n0 = (numStats + 1) >> 1;
|
|
n1 = (p->MinContext->NumStats + 1) >> 1;
|
|
if (n0 != n1)
|
|
p->MinContext->Stats = STATS_REF(ShrinkUnits(p, stats, n0, n1));
|
|
}
|
|
p->MinContext->SummFreq = (UInt16)(sumFreq + escFreq - (escFreq >> 1));
|
|
p->FoundState = STATS(p->MinContext);
|
|
}
|
|
|
|
CPpmd_See *Ppmd7_MakeEscFreq(CPpmd7 *p, unsigned numMasked, UInt32 *escFreq)
|
|
{
|
|
CPpmd_See *see;
|
|
unsigned nonMasked = p->MinContext->NumStats - numMasked;
|
|
if (p->MinContext->NumStats != 256)
|
|
{
|
|
see = p->See[(unsigned)p->NS2Indx[(size_t)nonMasked - 1]] +
|
|
(nonMasked < (unsigned)SUFFIX(p->MinContext)->NumStats - p->MinContext->NumStats) +
|
|
2 * (unsigned)(p->MinContext->SummFreq < 11 * p->MinContext->NumStats) +
|
|
4 * (unsigned)(numMasked > nonMasked) +
|
|
p->HiBitsFlag;
|
|
{
|
|
unsigned r = (see->Summ >> see->Shift);
|
|
see->Summ = (UInt16)(see->Summ - r);
|
|
*escFreq = r + (r == 0);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
see = &p->DummySee;
|
|
*escFreq = 1;
|
|
}
|
|
return see;
|
|
}
|
|
|
|
static void NextContext(CPpmd7 *p)
|
|
{
|
|
CTX_PTR c = CTX(SUCCESSOR(p->FoundState));
|
|
if (p->OrderFall == 0 && (Byte *)c > p->Text)
|
|
p->MinContext = p->MaxContext = c;
|
|
else
|
|
UpdateModel(p);
|
|
}
|
|
|
|
void Ppmd7_Update1(CPpmd7 *p)
|
|
{
|
|
CPpmd_State *s = p->FoundState;
|
|
s->Freq += 4;
|
|
p->MinContext->SummFreq += 4;
|
|
if (s[0].Freq > s[-1].Freq)
|
|
{
|
|
SwapStates(&s[0], &s[-1]);
|
|
p->FoundState = --s;
|
|
if (s->Freq > MAX_FREQ)
|
|
Rescale(p);
|
|
}
|
|
NextContext(p);
|
|
}
|
|
|
|
void Ppmd7_Update1_0(CPpmd7 *p)
|
|
{
|
|
p->PrevSuccess = (2 * p->FoundState->Freq > p->MinContext->SummFreq);
|
|
p->RunLength += p->PrevSuccess;
|
|
p->MinContext->SummFreq += 4;
|
|
if ((p->FoundState->Freq += 4) > MAX_FREQ)
|
|
Rescale(p);
|
|
NextContext(p);
|
|
}
|
|
|
|
void Ppmd7_UpdateBin(CPpmd7 *p)
|
|
{
|
|
p->FoundState->Freq = (Byte)(p->FoundState->Freq + (p->FoundState->Freq < 128 ? 1: 0));
|
|
p->PrevSuccess = 1;
|
|
p->RunLength++;
|
|
NextContext(p);
|
|
}
|
|
|
|
void Ppmd7_Update2(CPpmd7 *p)
|
|
{
|
|
p->MinContext->SummFreq += 4;
|
|
if ((p->FoundState->Freq += 4) > MAX_FREQ)
|
|
Rescale(p);
|
|
p->RunLength = p->InitRL;
|
|
UpdateModel(p);
|
|
}
|