HalpMmAllocCtxAlloc

__int64 __fastcall HalpMmAllocCtxAlloc(__int64 a1, __int64 a2){
  __int64 v2; 
  unsigned __int64 v3; 
  unsigned __int64 v4; 
  unsigned __int64 v5; 
  RTL_BITMAP *v6; 
  unsigned __int8 v7; 
  unsigned __int64 v8; 
  unsigned int SizeOfBitMap; 
  unsigned int v10; 
  unsigned int *Buffer; 
  unsigned int v12; 
  unsigned int v13; 
  __int64 v14; 
  int v15; 
  unsigned int v16; 
  unsigned int v17; 
  __int64 v18; 
  unsigned __int64 *v19; 
  __int64 v20; 
  unsigned __int64 v21; 
  unsigned __int64 v22; 
  int v23; 
  unsigned __int64 v24; 
  unsigned int v25; 
  bool v26; 
  unsigned int v27; 
  unsigned int v28; 
  __int64 v29; 
  __int64 v30; 
  __int64 *v31; 
  __int64 v32; 
  UINT64 v34; 
  char v35; 
  unsigned int v36; 
  bool v37; 
  bool v38; 
  __int64 v39; 
  unsigned int v40; 
  __int64 v41; 
  unsigned __int64 v42; 
  __int64 v43; 
  int v44; 
  unsigned int v45; 
  unsigned __int64 *v46; 
  __int64 v47; 
  __int64 v48; 
  int v49; 
  unsigned __int64 *v50; 
  __int64 v51; 
  unsigned int v52; 
  unsigned __int64 v53; 
  unsigned __int64 v54; 
  int v55; 
  __int64 v56; 
  __int64 v57; 
  __int64 v58; 
  int i; 
  __int64 v60; 
  unsigned int v61; 
  v2 = 0i64;
  if( !a2 )
    KeBugCheckEx(0xACu, 0i64, 0xA0A0ui64, (ULONG_PTR)"minkernel\\hals\\lib\\mm\\memory.c", 0xC04ui64);
  v3 = (a2 + 15) & 0xFFFFFFFFFFFFFFF0ui64;
  v4 = v3 + 16;
  if( v3 >= 0x1000 )
    v4 = (a2 + 15) & 0xFFFFFFFFFFFFFFF0ui64;
  v5 = v4 >> 4;
  if( v4 >= 0x1000 )
  {
    v4 = (v4 + 4095) & 0xFFFFFFFFFFFFF000ui64;
    v6 = (RTL_BITMAP *)HalpMmAllocCtxAllocBuffer(4096i64, v4);
    if( !v6 )
      return v2;
LABEL_29:
    v29 = 0i64;
    KeAcquireSpinLockRaiseToDpc(&qword_140C4B790, v34);
    LOBYTE(v8) = v35;
    goto LABEL_22;
  }
  KeAcquireSpinLockRaiseToDpc(&qword_140C4B790, a2);
  v6 = (RTL_BITMAP *)HalpNPPoolAllocCtx;
  v8 = v7;
  while( 1 )
  {
    if( v6 == (RTL_BITMAP *)&HalpNPPoolAllocCtx )
    {
      KxReleaseSpinLock(&qword_140C4B790);
      __writecr8(v8);
      v6 = (RTL_BITMAP *)HalpMmAllocCtxAllocBuffer(v57, 0x4000ui64);
      if( !v6 )
        return v2;
      goto LABEL_29;
    }
    SizeOfBitMap = v6[2].SizeOfBitMap;
    Buffer = v6[2].Buffer;
    v10 = (unsigned int)v6[1].Buffer;
    v12 = v10 < SizeOfBitMap ? v10 : 0;
    v13 = SizeOfBitMap - 1;
    if( !(_DWORD)v5 )
    {
      v28 = v12 & 0xFFFFFFF8;
      goto LABEL_21;
    }
    v14 = (__int64)v6[2].Buffer & 4;
    v58 = v14;
    v15 = v14 != 0 ? 0x20 : 0;
    for( i = v15; ; v15 = i )
    {
      v16 = v15 + v13;
      v17 = v15 + v12;
      v18 = (__int64)Buffer - (v14 != 0 ? 4 : 0);
      v60 = v18;
      if( v13 - v12 + 1 >= (unsigned int)v5 )
        break;
      v27 = -1;
LABEL_33:
      if( !v12 )
        goto LABEL_20;
      Buffer = v6[2].Buffer;
      v36 = v5 + v10;
      v12 = 0;
      if( (unsigned int)v5 + v10 > SizeOfBitMap )
        v36 = SizeOfBitMap;
      v13 = v36 - 1;
    }
    v19 = (unsigned __int64 *)(v18 + 8 * ((unsigned __int64)v17 >> 6));
    v20 = ((1i64 << (v17 & 0x3F)) - 1) | *v19;
    v61 = v16 - v5 + 1;
    v21 = (unsigned __int64)v61 >> 6;
    v22 = v18 + 8 * v21;
    if( (unsigned int)v5 > 0x7F )
    {
      v42 = v22 + 8;
      if( (v61 & 0x3F) == 0 )
        v42 = v18 + 8 * v21;
      if( v20 )
      {
        if( *++v19 )
        {
          v45 = v61;
          goto LABEL_65;
        }
        v38 = !_BitScanReverse64((unsigned __int64 *)&v43, v20);
        if( v38 )
          v44 = 64;
        else
          v44 = 63 - v43;
      }
      else
      {
        v44 = 0;
      }
      v45 = v61;
LABEL_61:
      v27 = ((unsigned int)(((__int64)v19 - v18) >> 3) << 6) - v44;
      if( v27 > v45 )
        goto LABEL_31;
      v46 = &v19[(unsigned int)(v5 - v44) >> 6];
      while( ++v19 != v46 )
      {
        if( *v19 )
          goto LABEL_65;
      }
      if( (((_BYTE)v5 - (_BYTE)v44) & 0x3F) != 0 )
      {
        v38 = !_BitScanForward64((unsigned __int64 *)&v48, *v19);
        if( v38 )
          LODWORD(v48) = 64;
        if( (unsigned int)v48 < (((_BYTE)v5 - (_BYTE)v44) & 0x3Fu) )
        {
LABEL_65:
          while( (unsigned __int64)v19 <= v42 )
          {
            if( !*++v19 )
            {
              v38 = !_BitScanReverse64((unsigned __int64 *)&v47, *(v19 - 1));
              if( v38 )
                v44 = 64;
              else
                v44 = 63 - v47;
              goto LABEL_61;
            }
          }
          goto LABEL_31;
        }
      }
    }
    else
    {
      v23 = 64;
      if( (unsigned int)v5 >= 0x40 )
      {
        do
        {
LABEL_40:
          v37 = v20 < 0;
          do
          {
            if( v37 )
            {
              if( (unsigned __int64)++v19 > v22 )
                goto LABEL_31;
              v20 = *v19;
              goto LABEL_40;
            }
            v38 = !_BitScanReverse64((unsigned __int64 *)&v39, v20);
            if( !v38 )
              v23 = 63 - v39;
            v27 = (((unsigned int)(((__int64)v19 - v18) >> 3) + 1) << 6) - v23;
            if( v27 > v61 )
              goto LABEL_31;
            v40 = v5 - v23;
            if( (_DWORD)v5 == v23 )
              goto LABEL_18;
            ++v19;
            v23 = 64;
            v20 = *v19;
            if( v40 < 0x40 )
              goto LABEL_50;
            v37 = v20 < 0;
          }
          while( v20 );
          v40 -= 64;
          if( !v40 )
            break;
          v20 = *++v19;
LABEL_50:
          v38 = !_BitScanForward64((unsigned __int64 *)&v41, v20);
          if( v38 )
            LODWORD(v41) = 64;
        }
        while( (unsigned int)v41 < v40 );
      }
      else
      {
        if( (unsigned int)v5 > 1 )
        {
          v49 = 0;
          v50 = (unsigned __int64 *)(v18 + 8 * ((unsigned __int64)v16 >> 6));
          while( v20 != -1 )
          {
LABEL_79:
            v38 = !_BitScanForward64((unsigned __int64 *)&v51, v20);
            if( v38 )
              LODWORD(v51) = 64;
            if( v49 + (int)v51 >= (unsigned int)v5 )
            {
              v55 = -v49;
LABEL_86:
              v27 = ((unsigned int)(((__int64)v19 - v60) >> 3) << 6) + v55;
              v26 = v27 <= v61;
              goto LABEL_17;
            }
            v52 = v4 >> 4;
            v53 = ~v20;
            while( 1 )
            {
              v53 &= v53 >> (v52 >> 1);
              if( !v53 )
                break;
              v52 -= v52 >> 1;
              if( v52 <= 1 )
              {
                _BitScanForward64(&v54, v53);
                v55 = v54;
                goto LABEL_86;
              }
            }
            if( v19 == v50 )
              goto LABEL_31;
            v38 = !_BitScanReverse64((unsigned __int64 *)&v56, v20);
            if( v38 )
              v49 = 64;
            else
              v49 = 63 - v56;
            v20 = *++v19;
          }
          while( (unsigned __int64)++v19 <= v22 )
          {
            v20 = *v19;
            if( *v19 != -1i64 )
            {
              v49 = 0;
              goto LABEL_79;
            }
          }
LABEL_31:
          v27 = -1;
LABEL_32:
          v10 = (unsigned int)v6[1].Buffer;
          v14 = v58;
          SizeOfBitMap = v6[2].SizeOfBitMap;
          goto LABEL_33;
        }
        while( v20 == -1 )
        {
          if( (unsigned __int64)++v19 > v22 )
            goto LABEL_31;
          v20 = *v19;
        }
        _BitScanForward64(&v24, ~v20);
        v25 = v24 + ((unsigned int)(((__int64)v19 - v18) >> 3) << 6);
        v26 = v25 <= v61;
        v27 = v25;
LABEL_17:
        if( !v26 )
          goto LABEL_31;
      }
    }
LABEL_18:
    if( v27 == -1 )
      goto LABEL_32;
    v27 -= i;
LABEL_20:
    v28 = v27;
LABEL_21:
    v29 = v28;
    if( v28 != 0xFFFFFFFFi64 )
      break;
    v6 = *(RTL_BITMAP **)&v6->SizeOfBitMap;
  }
LABEL_22:
  RtlSetBits(v6 + 2, (unsigned int)v29, (unsigned int)v5);
  LODWORD(v6[1].Buffer) = v5 + v29;
  v30 = *(_QWORD *)&v6->SizeOfBitMap;
  v31 = (__int64 *)v6->Buffer;
  if( *(RTL_BITMAP **)(*(_QWORD *)&v6->SizeOfBitMap + 8i64) != v6
    || (RTL_BITMAP *)*v31 != v6
    || (*v31 = v30,
        *(_QWORD *)(v30 + 8) = v31,
        v32 = HalpNPPoolAllocCtx,
        *(__int64 **)(HalpNPPoolAllocCtx + 8) != &HalpNPPoolAllocCtx) )
  {
    __fastfail(3u);
  }
  *(_QWORD *)&v6->SizeOfBitMap = HalpNPPoolAllocCtx;
  v6->Buffer = (unsigned int *)&HalpNPPoolAllocCtx;
  *(_QWORD *)(v32 + 8) = v6;
  HalpNPPoolAllocCtx = (__int64)v6;
  KxReleaseSpinLock(&qword_140C4B790);
  __writecr8((unsigned __int8)v8);
  v2 = *(_QWORD *)&v6[1].SizeOfBitMap + 16 * v29;
  if( v4 >= 0x1000 )
  {
    HIDWORD(v6[1].Buffer) = v5;
  }
  else
  {
    *(_QWORD *)v2 = v6;
    *(_DWORD *)(v2 + 8) = v5;
    v2 += 16i64;
  }
  return v2;
}

Referenced by: