Re: [Tinycc-devel] Regression on ARM

[Thomas Preud'homme]

On Wed, 21 Nov 2012 10:03:58 +0400, Kirill Smelkov wrote:
> On Tue, Nov 20, 2012 at 03:29:26PM +0100, address@hidden wrote:
> > Another regression is due to the unconditional activation of btest
> > in the list of tests to run. Indeed, there is no bound checking on
> > arm (and also C67 and il). This test should thus be run only for
> > architecture supporting it.
>
> Sorry, my fault, that was late at night. Does the following patch 
> fixes
> btest issue for you?
>
> ---- 8< ----
> From: Kirill Smelkov <address@hidden>
> Date: Wed, 21 Nov 2012 09:47:23 +0400
> Subject: [PATCH] tests: btest should only run on targets supporting 
> bcheck
>
> After 40a54c43 (Repair bounds-checking runtime), and in particular
> 5d648485 (Now btest pass!) `make test` was broken on ARCH != i386,
> because I've changed btest to unconditionally run on all arches.
>
> But bounds-checking itself is only supported on i386 and oops...
>
> My fault, fix it.

No need to blame yourself, this line is not necessary. Besides, this 
information can be extracted from git log/blame.

> Reported-by: Thomas Preud'homme <address@hidden>
> ---
>  tests/Makefile | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/tests/Makefile b/tests/Makefile
> index af1fdb8..ca581b0 100644
> --- a/tests/Makefile
> +++ b/tests/Makefile
> @@ -11,12 +11,16 @@ TESTS = libtest \
>                 test2 \
>                 test3 \
>                 speedtest \
> -               btest \
>                 weaktest
>
>                 # test4 # this test does not seem to work on any platform
>                 # asmtest # this test does not seem to work on any platform
>
> +# bounds-checking is supported only on i386
> +ifeq ($(ARCH),i386)
> +    TESTS += btest
> +endif
> +
>  # these should work too
>  # TESTS += test1 test2 speedtest btest weaktest

> --
> 1.8.0.289.g7a667bc

Yep it works but shouldn't you use the same filter-out method to be 
consistent with other disabled tests?

> > There was a test regression on ARM recently which I managed to
> > pinpoint to commit b2a02961b4407ca76db5a66ca5ae855cbfba4e8e. All I
> > can tell so far is that it's related to the addition of the test
> > builtin_frame_address_test.
>
> Thanks for the report.
>
> I'm new to arm - will try to setup arm cross-compiler toolchain and 
> see
> what is going on there, but that will probably take time. In the
> meantime, I'm having problem to build tcc arm cross compiler on i386:

I can maybe fix it myself if you have problem setting up your 
environment.

>     gcc -o arm-fpa-tcc tcc.c -DONE_SOURCE -DTCC_TARGET_ARM  -Wall -g
> -O2 -fno-strict-aliasing -Wno-pointer-sign -Wno-sign-compare
> -Wno-unused-result -mpreferred-stack-boundary=2 -march=i386
> -falign-functions=0 -m32 -lm -ldl
>     In file included from libtcc.c:50:0,
>                      from tcc.c:22:
>     arm-gen.c: In function ‘gfunc_call’:
>     arm-gen.c:1058:7: warning: implicit declaration of function
> ‘vfpr’ [-Wimplicit-function-declaration]
>     In file included from libtcc.c:42:0,
>                      from tcc.c:22:
>     tccpp.c: In function ‘macro_subst’:
>     tccpp.c:2806:12: warning: ‘*((void *)&cval+4)’ is used
> uninitialized in this function [-Wuninitialized]
>     /tmp/ccWBLnLc.o: In function `gfunc_call':
>     /home/kirr/src/tools/tinycc/arm-gen.c:1058: undefined reference 
> to `vfpr'
>     /home/kirr/src/tools/tinycc/arm-gen.c:1058: undefined reference 
> to `vfpr'
>     collect2: error: ld returned 1 exit status
>     Makefile:194: recipe for target 'arm-fpa-tcc' failed
>     make: *** [arm-fpa-tcc] Error 1
>
>
> could you please fix it, or tell me what is the workaround, so I 
> could
> try fixing tcc while working on cross-version of it?

Yes sure, I'm sorry. I broke build without vfp. I always tested with 
VFP in my tests.

> Also, while I'm studying how to setup arm toolchain, what is `objdump 
> -d`
> output on arm for gcc and tcc for the next source?
>
> ---- 8< ----
> void *bfa0()
> {
>     return __builtin_frame_address(0);
> }
>
> void *bfa1()
> {
>     return __builtin_frame_address(1);
> }
>
> void *bfa2()
> {
>     return __builtin_frame_address(2);
> }
> ---- 8< ----

*** tcc ***

00000000 <bfa0>:
   0:   e1a0c00d        mov     ip, sp
   4:   e92d5800        push    {fp, ip, lr}
   8:   e28db00c        add     fp, sp, #12
   c:   e1a00000        nop                     ; (mov r0, r0)
  10:   e28b0000        add     r0, fp, #0
  14:   e1a00000        nop                     ; (mov r0, r0)
  18:   e91ba800        ldmdb   fp, {fp, sp, pc}

0000001c <bfa1>:
  1c:   e1a0c00d        mov     ip, sp
  20:   e92d5800        push    {fp, ip, lr}
  24:   e28db00c        add     fp, sp, #12
  28:   e1a00000        nop                     ; (mov r0, r0)
  2c:   e59b0000        ldr     r0, [fp]
  30:   e1a00000        nop                     ; (mov r0, r0)
  34:   e91ba800        ldmdb   fp, {fp, sp, pc}

00000038 <bfa2>:
  38:   e1a0c00d        mov     ip, sp
  3c:   e92d5800        push    {fp, ip, lr}
  40:   e28db00c        add     fp, sp, #12
  44:   e24bd010        sub     sp, fp, #16
  48:   e59b0000        ldr     r0, [fp]
  4c:   e50b0010        str     r0, [fp, #-16]
  50:   e51be010        ldr     lr, [fp, #-16]
  54:   e59e0000        ldr     r0, [lr]
  58:   e1a00000        nop                     ; (mov r0, r0)
  5c:   e91ba800        ldmdb   fp, {fp, sp, pc}

*** gcc ***

00000000 <bfa0>:
   0:   b480            push    {r7}
   2:   af00            add     r7, sp, #0
   4:   463b            mov     r3, r7
   6:   4618            mov     r0, r3
   8:   46bd            mov     sp, r7
   a:   bc80            pop     {r7}
   c:   4770            bx      lr
   e:   bf00            nop

00000010 <bfa1>:
  10:   b480            push    {r7}
  12:   af00            add     r7, sp, #0
  14:   683b            ldr     r3, [r7, #0]
  16:   4618            mov     r0, r3
  18:   46bd            mov     sp, r7
  1a:   bc80            pop     {r7}
  1c:   4770            bx      lr
  1e:   bf00            nop

00000020 <bfa2>:
  20:   b480            push    {r7}
  22:   af00            add     r7, sp, #0
  24:   683b            ldr     r3, [r7, #0]
  26:   681b            ldr     r3, [r3, #0]
  28:   4618            mov     r0, r3
  2a:   46bd            mov     sp, r7
  2c:   bc80            pop     {r7}
  2e:   4770            bx      lr

> By the way, what arm variant I should test against - it seems there 
> are
> many? Another question: maybe you know, what is the most convenient 
> way
> to setup arm cross-toolchain on Debian GNU/Linux on i386?

The bug I experienced was with the hardfloat variant (that is, 
TCC_ARM_HARDFLOAT, TCC_ARM_EABI and TCC_ARM_VFP must be defined). Maybe 
the bug also happens on EABI but I can't tell for sure since I haven't 
tried.

> Thanks,
> Kirill

Thank to you :)

Thomas