tcg: fix register allocation with two aliased dead inputs

For TCG ops with two outputs registers (add2, sub2, div2, div2u), when
the same input temp is used for the two inputs aliased to the two
outputs, and when these inputs are both dead, the register allocation
code wrongly assigned the same register to the same output.

This happens for example with sub2 t1, t2, t3, t3, t4, t5, when t3 is
not used anymore after the TCG op.  In that case the same register is
used for t1, t2 and t3.

The fix is to look for already allocated aliased input when allocating
a dead aliased input and check that the register is not already
used.

Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Message-Id: <1433447228-29425-2-git-send-email-aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
1 file changed
tree: c85f3366cdd2a5bc1e5710f3af2428f838a75ed9
  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. target-alpha/
  30. target-arm/
  31. target-cris/
  32. target-i386/
  33. target-lm32/
  34. target-m68k/
  35. target-microblaze/
  36. target-mips/
  37. target-moxie/
  38. target-openrisc/
  39. target-ppc/
  40. target-s390x/
  41. target-sh4/
  42. target-sparc/
  43. target-tricore/
  44. target-unicore32/
  45. target-xtensa/
  46. tcg/
  47. tests/
  48. trace/
  49. ui/
  50. util/
  51. .exrc
  52. .gitignore
  53. .gitmodules
  54. .mailmap
  55. .travis.yml
  56. accel.c
  57. aio-posix.c
  58. aio-win32.c
  59. arch_init.c
  60. async.c
  61. balloon.c
  62. block.c
  63. blockdev-nbd.c
  64. blockdev.c
  65. blockjob.c
  66. bootdevice.c
  67. bt-host.c
  68. bt-vhci.c
  69. Changelog
  70. CODING_STYLE
  71. configure
  72. COPYING
  73. COPYING.LIB
  74. coroutine-gthread.c
  75. coroutine-sigaltstack.c
  76. coroutine-ucontext.c
  77. coroutine-win32.c
  78. cpu-exec.c
  79. cpus.c
  80. cputlb.c
  81. device-hotplug.c
  82. device_tree.c
  83. disas.c
  84. dma-helpers.c
  85. dump.c
  86. exec.c
  87. gdbstub.c
  88. HACKING
  89. hmp-commands.hx
  90. hmp.c
  91. hmp.h
  92. iohandler.c
  93. ioport.c
  94. iothread.c
  95. kvm-all.c
  96. kvm-stub.c
  97. LICENSE
  98. main-loop.c
  99. MAINTAINERS
  100. Makefile
  101. Makefile.objs
  102. Makefile.target
  103. memory.c
  104. memory_mapping.c
  105. module-common.c
  106. monitor.c
  107. nbd.c
  108. numa.c
  109. os-posix.c
  110. os-win32.c
  111. page_cache.c
  112. qapi-schema.json
  113. qdev-monitor.c
  114. qdict-test-data.txt
  115. qemu-bridge-helper.c
  116. qemu-char.c
  117. qemu-coroutine-io.c
  118. qemu-coroutine-lock.c
  119. qemu-coroutine-sleep.c
  120. qemu-coroutine.c
  121. qemu-doc.texi
  122. qemu-img-cmds.hx
  123. qemu-img.c
  124. qemu-img.texi
  125. qemu-io-cmds.c
  126. qemu-io.c
  127. qemu-log.c
  128. qemu-nbd.c
  129. qemu-nbd.texi
  130. qemu-options-wrapper.h
  131. qemu-options.h
  132. qemu-options.hx
  133. qemu-seccomp.c
  134. qemu-tech.texi
  135. qemu-timer.c
  136. qemu.nsi
  137. qemu.sasl
  138. qjson.c
  139. qmp-commands.hx
  140. qmp.c
  141. qtest.c
  142. README
  143. rules.mak
  144. savevm.c
  145. softmmu_template.h
  146. spice-qemu-char.c
  147. tcg-runtime.c
  148. tci.c
  149. thread-pool.c
  150. thunk.c
  151. tpm.c
  152. trace-events
  153. translate-all.c
  154. translate-all.h
  155. user-exec.c
  156. VERSION
  157. version.rc
  158. vl.c
  159. xen-common-stub.c
  160. xen-common.c
  161. xen-hvm-stub.c
  162. xen-hvm.c
  163. xen-mapcache.c