[Qemu-commits] [qemu/qemu] 240ce2: target-mips: fix branch in likely delay slot tcg a...

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/qemu/qemu
  Commit: 240ce26a0533a6e5ee472789fbfbd9f7f939197e
      
https://github.com/qemu/qemu/commit/240ce26a0533a6e5ee472789fbfbd9f7f939197e
  Author: James Hogan <address@hidden>
  Date:   2013-07-28 (Sun, 28 Jul 2013)

  Changed paths:
    M target-mips/translate.c

  Log Message:
  -----------
  target-mips: fix branch in likely delay slot tcg assert

When a branch delay slot contains another branch instruction, the code
generated raises an exception, however since is_branch==1,
handle_delay_slot() doesn't get called immediately. This means
ctx->bstate isn't set to BS_BRANCH, and the decoder continues decoding
until a non-branch instruction is found.

If the first branch was a branch likely instruction then each
instruction after it generates code for the unlikely case, to go to the
next tb starting after the delay slot. This results in multiple goto_tb
tcg ops being generated with the same exit number. When debug is enabled
this hits:

tcg-op.h:2589: tcg_gen_goto_tb: Assertion `(tcg_ctx.goto_tb_issue_mask & (1 << 
idx)) == 0' failed.

This is fixed by removing is_branch entirely, and calling
handle_delay_slot() if (ctx.hflags & MIPS_HFLAG_BMASK) was set prior to
the current instruction being decoded. This still prevents
handle_delay_slot() being called immediately after a branch but allows
it to still be called after a branch within a delay slot.

Signed-off-by: James Hogan <address@hidden>
Signed-off-by: Yongbok Kim <address@hidden>
Signed-off-by: Aurelien Jarno <address@hidden>


  Commit: cba5cb67becd66f8eae4177c4f95756f3f9bb77a
      
https://github.com/qemu/qemu/commit/cba5cb67becd66f8eae4177c4f95756f3f9bb77a
  Author: Andreas Färber <address@hidden>
  Date:   2013-07-28 (Sun, 28 Jul 2013)

  Changed paths:
    M hw/mips/mips_malta.c

  Log Message:
  -----------
  mips_malta: QOM cast cleanup

Signed-off-by: Andreas Färber <address@hidden>
Signed-off-by: Aurelien Jarno <address@hidden>


Compare: https://github.com/qemu/qemu/compare/4877866ee4fb...cba5cb67becd