[PATCH] tests/tcg: Replace -mpower8-vector with -mvsx

[PATCH] tests/tcg: Replace -mpower8-vector with -mvsx

[Ilya Leoshkevich]

[1] deprecated -mpower8-vector, resulting in:

    powerpc64-linux-gnu-gcc: warning: switch '-mpower8-vector' is no longer supported
    qemu/tests/tcg/ppc64/vsx_f2i_nan.c:4:15: error: expected ';' before 'float'
        4 | typedef vector float vsx_float32_vec_t;
          |               ^~~~~~

Similar to how this was done for the GCC testcases, replace
-mpower8-vector with -mvsx.

[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109987

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 tests/tcg/ppc64/Makefile.target | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/tests/tcg/ppc64/Makefile.target b/tests/tcg/ppc64/Makefile.target
index 1940886c737..d1b00d2bf09 100644
--- a/tests/tcg/ppc64/Makefile.target
+++ b/tests/tcg/ppc64/Makefile.target
@@ -6,7 +6,7 @@ VPATH += $(SRC_PATH)/tests/tcg/ppc64
 
 config-cc.mak: Makefile
 	$(quiet-@)( \
-	    $(call cc-option,-mpower8-vector,   CROSS_CC_HAS_POWER8_VECTOR); \
+	    $(call cc-option,-mvsx,             CROSS_CC_HAS_VSX); \
 	    $(call cc-option,-mpower10,         CROSS_CC_HAS_POWER10)) 3> config-cc.mak
 
 -include config-cc.mak
@@ -23,15 +23,15 @@ run-threadcount: threadcount
 run-plugin-threadcount-with-%:
 	$(call skip-test, $<, "BROKEN (flaky with clang) ")
 
-ifneq ($(CROSS_CC_HAS_POWER8_VECTOR),)
+ifneq ($(CROSS_CC_HAS_VSX),)
 PPC64_TESTS=bcdsub non_signalling_xscv
 endif
-$(PPC64_TESTS): CFLAGS += -mpower8-vector
+$(PPC64_TESTS): CFLAGS += -mvsx
 
-ifneq ($(CROSS_CC_HAS_POWER8_VECTOR),)
+ifneq ($(CROSS_CC_HAS_VSX),)
 PPC64_TESTS += vsx_f2i_nan
 endif
-vsx_f2i_nan: CFLAGS += -mpower8-vector -I$(SRC_PATH)/include
+vsx_f2i_nan: CFLAGS += -mvsx -I$(SRC_PATH)/include
 
 PPC64_TESTS += mtfsf
 PPC64_TESTS += mffsce
-- 
2.47.0

Re: [PATCH] tests/tcg: Replace -mpower8-vector with -mvsx

[Richard Henderson]

On 10/21/24 07:27, Ilya Leoshkevich wrote:
> [1] deprecated -mpower8-vector, resulting in:
> 
>      powerpc64-linux-gnu-gcc: warning: switch '-mpower8-vector' is no longer supported
>      qemu/tests/tcg/ppc64/vsx_f2i_nan.c:4:15: error: expected ';' before 'float'
>          4 | typedef vector float vsx_float32_vec_t;
>            |               ^~~~~~
> 
> Similar to how this was done for the GCC testcases, replace
> -mpower8-vector with -mvsx.
> 
> [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109987
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   tests/tcg/ppc64/Makefile.target | 10 +++++-----
>   1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/tests/tcg/ppc64/Makefile.target b/tests/tcg/ppc64/Makefile.target
> index 1940886c737..d1b00d2bf09 100644
> --- a/tests/tcg/ppc64/Makefile.target
> +++ b/tests/tcg/ppc64/Makefile.target
> @@ -6,7 +6,7 @@ VPATH += $(SRC_PATH)/tests/tcg/ppc64
>   
>   config-cc.mak: Makefile
>   	$(quiet-@)( \
> -	    $(call cc-option,-mpower8-vector,   CROSS_CC_HAS_POWER8_VECTOR); \
> +	    $(call cc-option,-mvsx,             CROSS_CC_HAS_VSX); \
>   	    $(call cc-option,-mpower10,         CROSS_CC_HAS_POWER10)) 3> config-cc.mak

I don't think this is quite right.
I think you need -mpower8 to get OPTION_MASK_P8_VECTOR set.

> +ifneq ($(CROSS_CC_HAS_VSX),)
>   PPC64_TESTS=bcdsub non_signalling_xscv

bcdsub is not in the base VSX instruction set, for instance.


r~

Re: [PATCH] tests/tcg: Replace -mpower8-vector with -mvsx

[Ilya Leoshkevich]

On Mon, 2024-10-21 at 19:59 -0700, Richard Henderson wrote:
> On 10/21/24 07:27, Ilya Leoshkevich wrote:
> > [1] deprecated -mpower8-vector, resulting in:
> > 
> >      powerpc64-linux-gnu-gcc: warning: switch '-mpower8-vector' is
> > no longer supported
> >      qemu/tests/tcg/ppc64/vsx_f2i_nan.c:4:15: error: expected ';'
> > before 'float'
> >          4 | typedef vector float vsx_float32_vec_t;
> >            |               ^~~~~~
> > 
> > Similar to how this was done for the GCC testcases, replace
> > -mpower8-vector with -mvsx.
> > 
> > [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109987
> > 
> > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> > ---
> >   tests/tcg/ppc64/Makefile.target | 10 +++++-----
> >   1 file changed, 5 insertions(+), 5 deletions(-)
> > 
> > diff --git a/tests/tcg/ppc64/Makefile.target
> > b/tests/tcg/ppc64/Makefile.target
> > index 1940886c737..d1b00d2bf09 100644
> > --- a/tests/tcg/ppc64/Makefile.target
> > +++ b/tests/tcg/ppc64/Makefile.target
> > @@ -6,7 +6,7 @@ VPATH += $(SRC_PATH)/tests/tcg/ppc64
> >   
> >   config-cc.mak: Makefile
> >   	$(quiet-@)( \
> > -	    $(call cc-option,-mpower8-vector,  
> > CROSS_CC_HAS_POWER8_VECTOR); \
> > +	    $(call cc-option,-mvsx,             CROSS_CC_HAS_VSX);
> > \
> >   	    $(call cc-option,-mpower10,        
> > CROSS_CC_HAS_POWER10)) 3> config-cc.mak
> 
> I don't think this is quite right.
> I think you need -mpower8 to get OPTION_MASK_P8_VECTOR set.

Do you mean -mcpu=power8? -mpower8 is a GAS option.

> 
> > +ifneq ($(CROSS_CC_HAS_VSX),)
> >   PPC64_TESTS=bcdsub non_signalling_xscv
> 
> bcdsub is not in the base VSX instruction set, for instance.
> 
> 
> r~

I was confused why -mvsx works in practice, so I spent some time and
managed to create a "hostile" gcc build, in which this is now a
problem, using:

    ./configure --target=powerpc64-linux-gnu --enable-checking \
                --disable-bootstrap \
                --with-as="$(which powerpc64-linux-gnu-as)"

The issue is masked by two things:

- GCC passes "-many" to GAS. GCC commit e154242724b0 ("[RS6000] Don't
  pass -many to the assembler") stops --enable-checking builds from
  doing this.

- binutils has the following line:

  /* The minimum supported cpu for 64-bit little-endian is power8.  */
  ppc_cpu |= ppc_parse_cpu (ppc_cpu, &sticky, "power8");

  so one needs to use the big-endian toolchain to see the problem.


I'll send a v2.

Re: [PATCH] tests/tcg: Replace -mpower8-vector with -mvsx

[Richard Henderson]

On 10/23/24 05:17, Ilya Leoshkevich wrote:
> On Mon, 2024-10-21 at 19:59 -0700, Richard Henderson wrote:
>> On 10/21/24 07:27, Ilya Leoshkevich wrote:
>>> [1] deprecated -mpower8-vector, resulting in:
>>>
>>>       powerpc64-linux-gnu-gcc: warning: switch '-mpower8-vector' is
>>> no longer supported
>>>       qemu/tests/tcg/ppc64/vsx_f2i_nan.c:4:15: error: expected ';'
>>> before 'float'
>>>           4 | typedef vector float vsx_float32_vec_t;
>>>             |               ^~~~~~
>>>
>>> Similar to how this was done for the GCC testcases, replace
>>> -mpower8-vector with -mvsx.
>>>
>>> [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109987
>>>
>>> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
>>> ---
>>>    tests/tcg/ppc64/Makefile.target | 10 +++++-----
>>>    1 file changed, 5 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/tests/tcg/ppc64/Makefile.target
>>> b/tests/tcg/ppc64/Makefile.target
>>> index 1940886c737..d1b00d2bf09 100644
>>> --- a/tests/tcg/ppc64/Makefile.target
>>> +++ b/tests/tcg/ppc64/Makefile.target
>>> @@ -6,7 +6,7 @@ VPATH += $(SRC_PATH)/tests/tcg/ppc64
>>>    
>>>    config-cc.mak: Makefile
>>>    	$(quiet-@)( \
>>> -	    $(call cc-option,-mpower8-vector,
>>> CROSS_CC_HAS_POWER8_VECTOR); \
>>> +	    $(call cc-option,-mvsx,             CROSS_CC_HAS_VSX);
>>> \
>>>    	    $(call cc-option,-mpower10,
>>> CROSS_CC_HAS_POWER10)) 3> config-cc.mak
>>
>> I don't think this is quite right.
>> I think you need -mpower8 to get OPTION_MASK_P8_VECTOR set.
> 
> Do you mean -mcpu=power8? -mpower8 is a GAS option.

It looks like I do, yes.
Also in that vein, -mpower10 has been marked WarnRemoved in gcc trunk.


> I was confused why -mvsx works in practice, so I spent some time and
> managed to create a "hostile" gcc build, in which this is now a
> problem, using:
> 
>      ./configure --target=powerpc64-linux-gnu --enable-checking \
>                  --disable-bootstrap \
>                  --with-as="$(which powerpc64-linux-gnu-as)"
> 
> The issue is masked by two things:
> 
> - GCC passes "-many" to GAS. GCC commit e154242724b0 ("[RS6000] Don't
>    pass -many to the assembler") stops --enable-checking builds from
>    doing this.
> 
> - binutils has the following line:
> 
>    /* The minimum supported cpu for 64-bit little-endian is power8.  */
>    ppc_cpu |= ppc_parse_cpu (ppc_cpu, &sticky, "power8");
> 
>    so one needs to use the big-endian toolchain to see the problem.

Ah hah!  Good sleuthing.


r~