Re: [Qemu-devel] qemu aborts with temp_save: Assertion `s->temps[temp].val_type == 2 || s->temps[temp].fixed_reg' failed

[Max Filippov]

On Thu, Jul 11, 2013 at 6:35 AM, Max Filippov <address@hidden> wrote:
> Hi Peter,
>
> I suddenly found qemu built with debug enabled aborting with an assertion on 
> one of xtensa tests:
>
> qemu-system-xtensa -M sim -cpu dc232b -nographic -semihosting  -kernel 
> ./test_sr.tst
> QEMU 1.4.50 monitor - type 'help' for more information
> (qemu) QEMU 1.4.50 monitor - type 'help' for more information
> (qemu) qemu-system-xtensa: tcg/tcg.c:1673: temp_save: Assertion 
> `s->temps[temp].val_type == 2 || s->temps[temp].fixed_reg' failed.

Déjà vu:

commit e5138db510efb61523be92c225d8c65eb985fff0
Author: Aurelien Jarno <address@hidden>
Date:   Sat Nov 24 11:53:55 2012 +0100

    tcg: mark local temps as MEM in dead_temp()

    In dead_temp, local temps should always be marked as back to memory,
    even if they have not been allocated (i.e. they are discared before
    cross a basic block).

    It fixes the following assertion in target-xtensa:

        qemu-system-xtensa: tcg/tcg.c:1665: temp_save: Assertion
`s->temps[temp].val_type == 2 || s->temps[temp].fixed_reg' failed.
        Aborted

> This happens in the mainline as well, bisection points to the following 
> commit:
>
> commit 378df4b23753a11be650af7664ca76bc75cb9f01
> Author: Peter Maydell <address@hidden>
> Date:   Fri Feb 22 18:10:03 2013 +0000
>
>     Handle CPU interrupts by inline checking of a flag
>
>
> I have the following traces when it happens, any idea of what could go wrong?
>
> OP:
>  ld_i32 loc0,env,$0xffffffffffffffc8
>  movi_i32 tmp1,$0x0
>  brcond_i32 loc0,tmp1,ne,$0x0
>  ---- 0xd0000fde
>
>  ---- 0xd0000fe0
>  movi_i32 tmp1,$0xd0000fe0
>  movi_i32 tmp2,$0x1
>  movi_i32 tmp3,$0x2
>  movi_i64 tmp4,$advance_ccount
>  call tmp4,$0x0,$0,env,tmp3
>  movi_i64 tmp4,$window_check
>  call tmp4,$0x0,$0,env,tmp1,tmp2
>  movi_i32 ar4,$0x0
>
>  ---- 0xd0000fe2
>  movi_i32 tmp1,$0xd00003f0
>  qemu_ld32 ar2,tmp1,$0x0
>
>  ---- 0xd0000fe5
>  movi_i32 tmp1,$0xd0000470
>  qemu_ld32 ar3,tmp1,$0x0
>
>  ---- 0xd0000fe8
>  mov_i32 tmp1,ar2
>  qemu_st32 ar3,tmp1,$0x0
>
>  ---- 0xd0000fea
>  movi_i32 tmp1,$0xd0000fea
>  movi_i32 tmp2,$0x0
>  movi_i32 tmp3,$0x4
>  movi_i64 tmp4,$advance_ccount
>  call tmp4,$0x0,$0,env,tmp3
>  movi_i64 tmp4,$exception_cause
>  call tmp4,$0x0,$0,env,tmp1,tmp2
>  mov_i32 env,ar4
>  set_label $0x0
>  exit_tb $0x7fffed6373b3
>
> qemu-system-xtensa: tcg/tcg.c:1673: temp_save: Assertion 
> `s->temps[temp].val_type == 2 || s->temps[temp].fixed_reg' failed.
>
> Program received signal SIGABRT, Aborted.
> [Switching to Thread 0x7fffed633700 (LWP 29011)]
> 0x00007ffff545bc55 in raise () from /lib64/libc.so.6
> ...
> (gdb) bt
> #0  temp_save (s=0x55555624a2a0 <tcg_ctx>, temp=6, allocated_regs=16400) at 
> tcg/tcg.c:1673
> #1  0x0000555555730fd6 in save_globals (s=0x55555624a2a0 <tcg_ctx>, 
> allocated_regs=16400) at tcg/tcg.c:1688
> #2  0x00005555557311b9 in tcg_reg_alloc_bb_end (s=0x55555624a2a0 <tcg_ctx>, 
> allocated_regs=16400) at tcg/tcg.c:1731
> #3  0x0000555555732e5d in tcg_gen_code_common (s=0x55555624a2a0 <tcg_ctx>, 
> gen_code_buf=0x7fffef240150 <code_gen_buffer+49488> "A\213nȉ\254$\200",
> search_pc=-1) at tcg/tcg.c:2300
> #4  0x0000555555733029 in tcg_gen_code (s=0x55555624a2a0 <tcg_ctx>, 
> gen_code_buf=0x7fffef240150 <code_gen_buffer+49488> "A\213nȉ\254$\200") at
> tcg/tcg.c:2356
> #5  0x0000555555733d3d in cpu_xtensa_gen_code (env=0x5555562b43c0, 
> tb=0x7fffed6373b0, gen_code_size_ptr=0x7fffed632a70) at translate-all.c:175
> #6  0x00005555557351cf in tb_gen_code (env=0x5555562b43c0, pc=3489664990, 
> cs_base=0, flags=0, cflags=0) at translate-all.c:958
> #7  0x00005555556c8216 in tb_find_slow (env=0x5555562b43c0, pc=3489664990, 
> cs_base=0, flags=0) at cpu-exec.c:141
> #8  0x00005555556c839d in tb_find_fast (env=0x5555562b43c0) at cpu-exec.c:168
> #9  0x00005555556c8722 in cpu_xtensa_exec (env=0x5555562b43c0) at 
> cpu-exec.c:583
> #10 0x00005555556cb719 in tcg_cpu_exec (env=0x5555562b43c0) at cpus.c:1117
> #11 0x00005555556cb850 in tcg_exec_all () at cpus.c:1150
> #12 0x00005555556cab40 in qemu_tcg_cpu_thread_fn (arg=0x5555562b42b0) at 
> cpus.c:843
> #13 0x00007ffff64d0d15 in start_thread () from /lib64/libpthread.so.0
> #14 0x00007ffff551853d in clone () from /lib64/libc.so.6
> (gdb) f 4
> #4  0x0000555555730f85 in temp_save (s=0x55555624a2a0 <tcg_ctx>, temp=6, 
> allocated_regs=16400) at tcg/tcg.c:1673
> 1673        assert(s->temps[temp].val_type == TEMP_VAL_MEM || 
> s->temps[temp].fixed_reg);
> (gdb) p s->temps[temp]
> $2 = {
>   base_type = TCG_TYPE_I32,
>   type = TCG_TYPE_I32,
>   val_type = 1,
>   reg = 5,
>   val = 0,
>   mem_reg = 14,
>   mem_offset = 24,
>   fixed_reg = 0,
>   mem_coherent = 1,
>   mem_allocated = 1,
>   temp_local = 0,
>   temp_allocated = 0,
>   next_free_temp = 0,
>   name = 0x5555557826e0 "ar4"
> }
>
> --
> Thanks.
> -- Max



-- 
Thanks.
-- Max