hbitmap: add hbitmap_merge

We add a bitmap merge operation to assist in error cases
where we wish to combine two bitmaps together.

This is algorithmically O(bits) provided HBITMAP_LEVELS remains
constant. For a full bitmap on a 64bit machine:
sum(bits/64^k, k, 0, HBITMAP_LEVELS) ~= 1.01587 * bits

We may be able to improve running speed for particularly sparse
bitmaps by using iterators, but the running time for dense maps
will be worse.

We present the simpler solution first, and we can refine it later
if needed.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-8-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2 files changed
tree: 32499b1555c9e8130a1990392d7ba58eeafb8a84
  1. audio/
  2. backends/
  3. block/
  4. bsd-user/
  5. default-configs/
  6. disas/
  7. docs/
  8. fpu/
  9. fsdev/
  10. gdb-xml/
  11. hw/
  12. include/
  13. libcacard/
  14. libdecnumber/
  15. linux-headers/
  16. linux-user/
  17. migration/
  18. net/
  19. pc-bios/
  20. po/
  21. qapi/
  22. qga/
  23. qobject/
  24. qom/
  25. roms/
  26. scripts/
  27. slirp/
  28. stubs/
  29. sysconfigs/
  30. target-alpha/
  31. target-arm/
  32. target-cris/
  33. target-i386/
  34. target-lm32/
  35. target-m68k/
  36. target-microblaze/
  37. target-mips/
  38. target-moxie/
  39. target-openrisc/
  40. target-ppc/
  41. target-s390x/
  42. target-sh4/
  43. target-sparc/
  44. target-tricore/
  45. target-unicore32/
  46. target-xtensa/
  47. tcg/
  48. tests/
  49. trace/
  50. ui/
  51. util/
  52. .exrc
  53. .gitignore
  54. .gitmodules
  55. .mailmap
  56. .travis.yml
  57. accel.c
  58. aio-posix.c
  59. aio-win32.c
  60. arch_init.c
  61. async.c
  62. balloon.c
  63. block.c
  64. blockdev-nbd.c
  65. blockdev.c
  66. blockjob.c
  67. bootdevice.c
  68. bt-host.c
  69. bt-vhci.c
  70. Changelog
  71. CODING_STYLE
  72. configure
  73. COPYING
  74. COPYING.LIB
  75. coroutine-gthread.c
  76. coroutine-sigaltstack.c
  77. coroutine-ucontext.c
  78. coroutine-win32.c
  79. cpu-exec.c
  80. cpus.c
  81. cputlb.c
  82. device-hotplug.c
  83. device_tree.c
  84. disas.c
  85. dma-helpers.c
  86. dump.c
  87. exec.c
  88. gdbstub.c
  89. HACKING
  90. hmp-commands.hx
  91. hmp.c
  92. hmp.h
  93. iohandler.c
  94. ioport.c
  95. iothread.c
  96. kvm-all.c
  97. kvm-stub.c
  98. LICENSE
  99. main-loop.c
  100. MAINTAINERS
  101. Makefile
  102. Makefile.objs
  103. Makefile.target
  104. memory.c
  105. memory_mapping.c
  106. module-common.c
  107. monitor.c
  108. nbd.c
  109. numa.c
  110. os-posix.c
  111. os-win32.c
  112. page_cache.c
  113. qapi-schema.json
  114. qdev-monitor.c
  115. qdict-test-data.txt
  116. qemu-bridge-helper.c
  117. qemu-char.c
  118. qemu-coroutine-io.c
  119. qemu-coroutine-lock.c
  120. qemu-coroutine-sleep.c
  121. qemu-coroutine.c
  122. qemu-doc.texi
  123. qemu-img-cmds.hx
  124. qemu-img.c
  125. qemu-img.texi
  126. qemu-io-cmds.c
  127. qemu-io.c
  128. qemu-log.c
  129. qemu-nbd.c
  130. qemu-nbd.texi
  131. qemu-options-wrapper.h
  132. qemu-options.h
  133. qemu-options.hx
  134. qemu-seccomp.c
  135. qemu-tech.texi
  136. qemu-timer.c
  137. qemu.nsi
  138. qemu.sasl
  139. qjson.c
  140. qmp-commands.hx
  141. qmp.c
  142. qtest.c
  143. README
  144. rules.mak
  145. savevm.c
  146. softmmu_template.h
  147. spice-qemu-char.c
  148. tcg-runtime.c
  149. tci.c
  150. thread-pool.c
  151. thunk.c
  152. tpm.c
  153. trace-events
  154. translate-all.c
  155. translate-all.h
  156. user-exec.c
  157. VERSION
  158. version.rc
  159. vl.c
  160. xen-common-stub.c
  161. xen-common.c
  162. xen-hvm-stub.c
  163. xen-hvm.c
  164. xen-mapcache.c