ARM: Disable safepoints in JITted code

[Pavel Tisnovsky]

Andrew,

thanks for info. I'll add this patch to the IcedTea I'm (still!) building.

Pavel

Andrew Haley wrote:
> JIT safepoints cause odd crashes.  This patch temporarily disables
> them until I debug the problem.
> 
> Andrew.
> 
> 
> 2011-12-22  Andrew Haley  <aph at redhat.com>
> 
>         * arm_port/hotspot/src/cpu/zero/vm/thumb2.cpp (Thumb2_Safepoint):
>         Disable.
> 
> diff -r cf80d2049346 -r e937f2726d70 arm_port/hotspot/src/cpu/zero/vm/thumb2.cpp
> --- a/arm_port/hotspot/src/cpu/zero/vm/thumb2.cpp       Tue Dec 20 13:49:11 2011 -0500
> +++ b/arm_port/hotspot/src/cpu/zero/vm/thumb2.cpp       Thu Dec 22 16:47:21 2011 +0000
> @@ -4344,6 +4344,8 @@
>  // Helper_SafePoint.
>  void Thumb2_Safepoint(Thumb2_Info *jinfo, int stackdepth)
>  {
> +#if 0  // Causes maysterious segfaults
> +  Thumb2_Flush(jinfo);
>    int r_tmp = Thumb2_Tmp(jinfo, 0);
>    mov_imm(jinfo->codebuf, r_tmp, (u32)SafepointSynchronize::address_of_state());
>    ldr_imm(jinfo->codebuf, r_tmp, r_tmp, 0, 0, 0);
> @@ -4355,6 +4357,7 @@
>    Thumb2_restore_locals(jinfo, stackdepth);
>      bcc_patch(jinfo->codebuf, COND_NE, loc);
>    }
> +#endif
>  }
> 
>  int Thumb2_Branch(Thumb2_Info *jinfo, unsigned bci, unsigned cond, int stackdepth)
>