[ARM/testsuite,6/7,ping] Force soft float in ARMv6-M and ARMv8-M Baseline options

Ping?

Best regards,

Thomas

On 28/10/16 10:49, Thomas Preudhomme wrote:
> On 22/09/16 16:47, Richard Earnshaw (lists) wrote:

>> On 22/09/16 15:51, Thomas Preudhomme wrote:

>>> Sorry, noticed an error in the patch. It was not caught during testing

>>> because GCC was built with --with-mode=thumb. Correct patch attached.

>>>

>>> Best regards,

>>>

>>> Thomas

>>>

>>> On 22/09/16 14:49, Thomas Preudhomme wrote:

>>>> Hi,

>>>>

>>>> ARMv6-M and ARMv8-M Baseline only support soft float ABI. Therefore, the

>>>> arm_arch_v8m_base add option should pass -mfloat-abi=soft, much like

>>>> -mthumb is

>>>> passed for architectures that only support Thumb instruction set. This

>>>> patch

>>>> adds -mfloat-abi=soft to both arm_arch_v6m and arm_arch_v8m_base add

>>>> options.

>>>> Patch is in attachment.

>>>>

>>>> ChangeLog entry is as follows:

>>>>

>>>> *** gcc/testsuite/ChangeLog ***

>>>>

>>>> 2016-07-15  Thomas Preud'homme  <thomas.preudhomme@arm.com>

>>>>

>>>>         * lib/target-supports.exp (add_options_for_arm_arch_v6m): Add

>>>>         -mfloat-abi=soft option.

>>>>         (add_options_for_arm_arch_v8m_base): Likewise.

>>>>

>>>>

>>>> Is this ok for trunk?

>>>>

>>>> Best regards,

>>>>

>>>> Thomas

>>>

>>> 6_softfloat_testing_v6m_v8m_baseline.patch

>>>

>>>

>>> diff --git a/gcc/testsuite/lib/target-supports.exp

>>> b/gcc/testsuite/lib/target-supports.exp

>>> index

>>> 0dabea0850124947a7fe333e0b94c4077434f278..b5d72f1283be6a6e4736a1d20936e169c1384398

>>> 100644

>>> --- a/gcc/testsuite/lib/target-supports.exp

>>> +++ b/gcc/testsuite/lib/target-supports.exp

>>> @@ -3540,24 +3540,25 @@ proc check_effective_target_arm_fp16_hw { } {

>>>  # Usage: /* { dg-require-effective-target arm_arch_v5_ok } */

>>>  #        /* { dg-add-options arm_arch_v5 } */

>>>  #     /* { dg-require-effective-target arm_arch_v5_multilib } */

>>> -foreach { armfunc armflag armdef } { v4 "-march=armv4 -marm" __ARM_ARCH_4__

>>> -                     v4t "-march=armv4t" __ARM_ARCH_4T__

>>> -                     v5 "-march=armv5 -marm" __ARM_ARCH_5__

>>> -                     v5t "-march=armv5t" __ARM_ARCH_5T__

>>> -                     v5te "-march=armv5te" __ARM_ARCH_5TE__

>>> -                     v6 "-march=armv6" __ARM_ARCH_6__

>>> -                     v6k "-march=armv6k" __ARM_ARCH_6K__

>>> -                     v6t2 "-march=armv6t2" __ARM_ARCH_6T2__

>>> -                     v6z "-march=armv6z" __ARM_ARCH_6Z__

>>> -                     v6m "-march=armv6-m -mthumb" __ARM_ARCH_6M__

>>> -                     v7a "-march=armv7-a" __ARM_ARCH_7A__

>>> -                     v7r "-march=armv7-r" __ARM_ARCH_7R__

>>> -                     v7m "-march=armv7-m -mthumb" __ARM_ARCH_7M__

>>> -                     v7em "-march=armv7e-m -mthumb" __ARM_ARCH_7EM__

>>> -                     v8a "-march=armv8-a" __ARM_ARCH_8A__

>>> -                     v8_1a "-march=armv8.1a" __ARM_ARCH_8A__

>>> -                     v8m_base "-march=armv8-m.base -mthumb"

>>> __ARM_ARCH_8M_BASE__

>>> -                     v8m_main "-march=armv8-m.main -mthumb"

>>> __ARM_ARCH_8M_MAIN__ } {

>>> +foreach { armfunc armflag armdef } {

>>> +    v4 "-march=armv4 -marm" __ARM_ARCH_4__

>>> +    v4t "-march=armv4t" __ARM_ARCH_4T__

>>> +    v5 "-march=armv5 -marm" __ARM_ARCH_5__

>>> +    v5t "-march=armv5t" __ARM_ARCH_5T__

>>> +    v5te "-march=armv5te" __ARM_ARCH_5TE__

>>> +    v6 "-march=armv6" __ARM_ARCH_6__

>>> +    v6k "-march=armv6k" __ARM_ARCH_6K__

>>> +    v6t2 "-march=armv6t2" __ARM_ARCH_6T2__

>>> +    v6z "-march=armv6z" __ARM_ARCH_6Z__

>>> +    v6m "-march=armv6-m -mthumb -mfloat-abi=soft" __ARM_ARCH_6M__

>>> +    v7a "-march=armv7-a" __ARM_ARCH_7A__

>>> +    v7r "-march=armv7-r" __ARM_ARCH_7R__

>>> +    v7m "-march=armv7-m -mthumb" __ARM_ARCH_7M__

>>> +    v7em "-march=armv7e-m -mthumb" __ARM_ARCH_7EM__

>>> +    v8a "-march=armv8-a" __ARM_ARCH_8A__

>>> +    v8_1a "-march=armv8.1a" __ARM_ARCH_8A__

>>> +    v8m_base "-march=armv8-m.base -mthumb -mfloat-abi=soft"

>>> __ARM_ARCH_8M_BASE__

>>> +    v8m_main "-march=armv8-m.main -mthumb" __ARM_ARCH_8M_MAIN__ } {

>>>      eval [string map [list FUNC $armfunc FLAG $armflag DEF $armdef ] {

>>>      proc check_effective_target_arm_arch_FUNC_ok { } {

>>>          if { [ string match "*-marm*" "FLAG" ] &&

>>>

>>

>> I think if you're going to do this you need to also check that changing

>> the ABI in this way isn't incompatible with other aspects of how the

>> user has invoked dejagnu.

>

> The reason this patch was made is that without it dg-require-effective-target

> arm_arch_v8m_base_ok evaluates to true for an arm-none-linux-gnueabihf toolchain

> but then any testcase containing a function for such a target (such as the

> atomic-op-* in gcc.target/arm) will error out because ARMv8-M Baseline does not

> support hard float ABI.

>

> I see 2 ways to fix this:

>

> 1) the approach taken in this patch, ie saying that to select ARMv8-M baseline

> architecture you need the right -march, -mthumb but also the right float ABI.

>

> Note that the comment at the top of that procedure says:

> # Creates a series of routines that return 1 if the given architecture

> # can be selected and a routine to give the flags to select that architecture

>

> 2) Add a function to the assembly that is used to test support for the

> architecture.

>

> The reason I favor the first one is that it enables more test while the second

> test would just skip ARMv6-M and ARMv8-M Baseline tests for

> arm-none-linux-gnueabihf toolchains.

>

> Is this patch ok for trunk?

>

> Best regards,

>

> Thomas