| /* ----------------------------------------------------------------------- * |
| * |
| * Copyright 1996-2009 The NASM Authors - All Rights Reserved |
| * See the file AUTHORS included with the NASM distribution for |
| * the specific copyright holders. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following |
| * conditions are met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following |
| * disclaimer in the documentation and/or other materials provided |
| * with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
| * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
| * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
| * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, |
| * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| * ----------------------------------------------------------------------- */ |
| |
| /* |
| * sync.c the Netwide Disassembler synchronisation processing module |
| */ |
| |
| #include "compiler.h" |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <limits.h> |
| |
| #include "nasmlib.h" |
| #include "sync.h" |
| |
| #define SYNC_MAX_SHIFT 31 |
| #define SYNC_MAX_SIZE (1U << SYNC_MAX_SHIFT) |
| |
| /* initial # of sync points (*must* be power of two)*/ |
| #define SYNC_INITIAL_CHUNK (1U << 12) |
| |
| /* |
| * This lot manages the current set of sync points by means of a |
| * heap (priority queue) structure. |
| */ |
| |
| static struct Sync { |
| uint64_t pos; |
| uint32_t length; |
| } *synx; |
| |
| static uint32_t max_synx, nsynx; |
| |
| static inline void swap_sync(uint32_t dst, uint32_t src) |
| { |
| struct Sync t = synx[dst]; |
| synx[dst] = synx[src]; |
| synx[src] = t; |
| } |
| |
| void init_sync(void) |
| { |
| max_synx = SYNC_INITIAL_CHUNK; |
| synx = nasm_malloc((max_synx + 1) * sizeof(*synx)); |
| nsynx = 0; |
| } |
| |
| void add_sync(uint64_t pos, uint32_t length) |
| { |
| uint32_t i; |
| |
| if (nsynx >= max_synx) { |
| if (max_synx >= SYNC_MAX_SIZE) /* too many sync points! */ |
| return; |
| max_synx = (max_synx << 1); |
| synx = nasm_realloc(synx, (max_synx + 1) * sizeof(*synx)); |
| } |
| |
| nsynx++; |
| synx[nsynx].pos = pos; |
| synx[nsynx].length = length; |
| |
| for (i = nsynx; i > 1; i /= 2) { |
| if (synx[i / 2].pos > synx[i].pos) |
| swap_sync(i / 2, i); |
| } |
| } |
| |
| uint64_t next_sync(uint64_t position, uint32_t *length) |
| { |
| while (nsynx > 0 && synx[1].pos + synx[1].length <= position) { |
| uint32_t i, j; |
| |
| swap_sync(nsynx, 1); |
| nsynx--; |
| |
| i = 1; |
| while (i * 2 <= nsynx) { |
| j = i * 2; |
| if (synx[j].pos < synx[i].pos && |
| (j + 1 > nsynx || synx[j + 1].pos > synx[j].pos)) { |
| swap_sync(j, i); |
| i = j; |
| } else if (j + 1 <= nsynx && synx[j + 1].pos < synx[i].pos) { |
| swap_sync(j + 1, i); |
| i = j + 1; |
| } else |
| break; |
| } |
| } |
| |
| if (nsynx > 0) { |
| if (length) |
| *length = synx[1].length; |
| return synx[1].pos; |
| } else { |
| if (length) |
| *length = 0L; |
| return 0; |
| } |
| } |