[PATCH] arm: respect both __ARM_ARCH_6KZ__ and __ARM_ARCH_6ZK__ macros

[PATCH] arm: respect both __ARM_ARCH_6KZ__ and __ARM_ARCH_6ZK__ macros

[Andre McCurdy]

6KZ is the correct form, 6ZK is a gcc specific historical typo.
Respect both for the widest compatibility with clang and older
versions of gcc.

Signed-off-by: Andre McCurdy <armccurdy@gmail.com>
---
 arch/arm/atomic_arch.h  | 2 +-
 arch/arm/pthread_arch.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/atomic_arch.h b/arch/arm/atomic_arch.h
index c5c56f8..d1d09d8 100644
--- a/arch/arm/atomic_arch.h
+++ b/arch/arm/atomic_arch.h
@@ -7,7 +7,7 @@
 extern uintptr_t __attribute__((__visibility__("hidden")))
 	__a_cas_ptr, __a_barrier_ptr;
 
-#if ((__ARM_ARCH_6__ || __ARM_ARCH_6K__ || __ARM_ARCH_6ZK__) && !__thumb__) \
+#if ((__ARM_ARCH_6__ || __ARM_ARCH_6K__ || __ARM_ARCH_6KZ__ || __ARM_ARCH_6ZK__) && !__thumb__) \
  || __ARM_ARCH_7A__ || __ARM_ARCH_7R__ ||  __ARM_ARCH >= 7
 
 #define a_ll a_ll
diff --git a/arch/arm/pthread_arch.h b/arch/arm/pthread_arch.h
index 197752e..6657e19 100644
--- a/arch/arm/pthread_arch.h
+++ b/arch/arm/pthread_arch.h
@@ -1,4 +1,4 @@
-#if ((__ARM_ARCH_6K__ || __ARM_ARCH_6ZK__) && !__thumb__) \
+#if ((__ARM_ARCH_6K__ || __ARM_ARCH_6KZ__ || __ARM_ARCH_6ZK__) && !__thumb__) \
  || __ARM_ARCH_7A__ || __ARM_ARCH_7R__ || __ARM_ARCH >= 7
 
 static inline pthread_t __pthread_self()
-- 
1.9.1

Re: [PATCH] arm: respect both __ARM_ARCH_6KZ__ and __ARM_ARCH_6ZK__ macros

[Rich Felker]

On Wed, Nov 29, 2017 at 09:57:55PM -0800, Andre McCurdy wrote:
> 6KZ is the correct form, 6ZK is a gcc specific historical typo.
> Respect both for the widest compatibility with clang and older
> versions of gcc.

Probably ok, but is it needed? Ideally we would just use
__ARM_ARCH>=N, but old gcc lacked __ARM_ARCH, thus necessitating all
the awful cases.

Rich


> Signed-off-by: Andre McCurdy <armccurdy@gmail.com>
> ---
>  arch/arm/atomic_arch.h  | 2 +-
>  arch/arm/pthread_arch.h | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/atomic_arch.h b/arch/arm/atomic_arch.h
> index c5c56f8..d1d09d8 100644
> --- a/arch/arm/atomic_arch.h
> +++ b/arch/arm/atomic_arch.h
> @@ -7,7 +7,7 @@
>  extern uintptr_t __attribute__((__visibility__("hidden")))
>  	__a_cas_ptr, __a_barrier_ptr;
>  
> -#if ((__ARM_ARCH_6__ || __ARM_ARCH_6K__ || __ARM_ARCH_6ZK__) && !__thumb__) \
> +#if ((__ARM_ARCH_6__ || __ARM_ARCH_6K__ || __ARM_ARCH_6KZ__ || __ARM_ARCH_6ZK__) && !__thumb__) \
>   || __ARM_ARCH_7A__ || __ARM_ARCH_7R__ ||  __ARM_ARCH >= 7
>  
>  #define a_ll a_ll
> diff --git a/arch/arm/pthread_arch.h b/arch/arm/pthread_arch.h
> index 197752e..6657e19 100644
> --- a/arch/arm/pthread_arch.h
> +++ b/arch/arm/pthread_arch.h
> @@ -1,4 +1,4 @@
> -#if ((__ARM_ARCH_6K__ || __ARM_ARCH_6ZK__) && !__thumb__) \
> +#if ((__ARM_ARCH_6K__ || __ARM_ARCH_6KZ__ || __ARM_ARCH_6ZK__) && !__thumb__) \
>   || __ARM_ARCH_7A__ || __ARM_ARCH_7R__ || __ARM_ARCH >= 7
>  
>  static inline pthread_t __pthread_self()
> -- 
> 1.9.1

Re: [PATCH] arm: respect both __ARM_ARCH_6KZ__ and __ARM_ARCH_6ZK__ macros

[Andre McCurdy]

On Wed, Nov 29, 2017 at 10:01 PM, Rich Felker <dalias@libc.org> wrote:
> On Wed, Nov 29, 2017 at 09:57:55PM -0800, Andre McCurdy wrote:
>> 6KZ is the correct form, 6ZK is a gcc specific historical typo.
>> Respect both for the widest compatibility with clang and older
>> versions of gcc.
>
> Probably ok, but is it needed?

As far as I know, __ARM_ARCH_6ZK__ is gcc specific and clang only ever
defines __ARM_ARCH_6KZ__. Older versions of gcc only define
__ARM_ARCH_6ZK__ and newer versions of gcc define both
__ARM_ARCH_6KZ__ and __ARM_ARCH_6ZK__.

> Ideally we would just use
> __ARM_ARCH>=N, but old gcc lacked __ARM_ARCH, thus necessitating all
> the awful cases.

In atomic_arch.h, replacing the current ARMv6 tests with __ARM_ARCH >=
6 would be OK (if we could rely on __ARM_ARCH).

For pthread_arch.h, there are ARMv6 cores which lack the c13
coprocessor thread and process ID registers so __ARM_ARCH >= 6
wouldn't be fine grained enough.

Re: [PATCH] arm: respect both __ARM_ARCH_6KZ__ and __ARM_ARCH_6ZK__ macros

[Rich Felker]

On Wed, Nov 29, 2017 at 11:20:48PM -0800, Andre McCurdy wrote:
> On Wed, Nov 29, 2017 at 10:01 PM, Rich Felker <dalias@libc.org> wrote:
> > On Wed, Nov 29, 2017 at 09:57:55PM -0800, Andre McCurdy wrote:
> >> 6KZ is the correct form, 6ZK is a gcc specific historical typo.
> >> Respect both for the widest compatibility with clang and older
> >> versions of gcc.
> >
> > Probably ok, but is it needed?
> 
> As far as I know, __ARM_ARCH_6ZK__ is gcc specific and clang only ever
> defines __ARM_ARCH_6KZ__. Older versions of gcc only define
> __ARM_ARCH_6ZK__ and newer versions of gcc define both
> __ARM_ARCH_6KZ__ and __ARM_ARCH_6ZK__.
> 
> > Ideally we would just use
> > __ARM_ARCH>=N, but old gcc lacked __ARM_ARCH, thus necessitating all
> > the awful cases.
> 
> In atomic_arch.h, replacing the current ARMv6 tests with __ARM_ARCH >=
> 6 would be OK (if we could rely on __ARM_ARCH).
> 
> For pthread_arch.h, there are ARMv6 cores which lack the c13
> coprocessor thread and process ID registers so __ARM_ARCH >= 6
> wouldn't be fine grained enough.

I see. That's the core issue here -- that it's needed to choose the
right (or at least optimal) thread pointer access method for v6 vs
v6kz.

Rich