diff options
| author | Yann E. MORIN <yann.morin.1998@anciens.enib.fr> | 2011-01-09 01:45:09 +0100 |
|---|---|---|
| committer | Khem Raj <raj.khem@gmail.com> | 2011-06-11 00:12:22 -0700 |
| commit | 7a246fda8e3bd2067d44e01c30c8ce761dad39a8 (patch) | |
| tree | dfff27e27af92783d8f81176ad24717e4fbdf0d2 | |
| parent | 3862c65a05983b2b18cb7884a124a905828f7a18 (diff) | |
ARM: detect BX availibility at build time
The "use BX" option is now a suggestion that BX be used if available.
Use a macro to detect if BX is available at build time. If so, and
the user requested it be used, then use it. Otherwise, error out.
Macro courtesy Khem RAJ:
http://lists.uclibc.org/pipermail/uclibc/2009-April/042301.html
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Cc: Khem Raj <raj.khem@gmail.com>
Cc: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
Cc: Carmelo AMOROSO <carmelo.amoroso@st.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
| -rw-r--r-- | extra/Configs/Config.arm | 4 | ||||
| -rw-r--r-- | libc/sysdeps/linux/arm/bits/arm_asm.h | 9 |
2 files changed, 11 insertions, 2 deletions
diff --git a/extra/Configs/Config.arm b/extra/Configs/Config.arm index 4ab7da0d1..0bb2971a9 100644 --- a/extra/Configs/Config.arm +++ b/extra/Configs/Config.arm @@ -33,4 +33,6 @@ config COMPILE_IN_THUMB_MODE config USE_BX bool "Use BX in function return" help - Use BX instruction for THUMB aware architectures. + Say 'y' to use BX to return from functions on your thumb-aware + processor. Say 'y' if you need to use interworking. Say 'n' if not. + It is safe to say 'y' even if you're not doing interworking. diff --git a/libc/sysdeps/linux/arm/bits/arm_asm.h b/libc/sysdeps/linux/arm/bits/arm_asm.h index 1d87df6eb..921c9a3c9 100644 --- a/libc/sysdeps/linux/arm/bits/arm_asm.h +++ b/libc/sysdeps/linux/arm/bits/arm_asm.h @@ -24,5 +24,12 @@ #define THUMB1_ONLY 1 #endif -#endif /* _ARM_ASM_H */ +#if defined(__USE_BX__) +# if ( defined (__ARM_ARCH_2__) || defined (__ARM_ARCH_3__) \ + || defined (__ARM_ARCH_3M__) || defined (__ARM_ARCH_4__) \ + ) +# error Use of BX was requested, but is not available on the target processor. +# endif /* ARCH level */ +#endif /* __USE_BX__ */ +#endif /* _ARM_ASM_H */ |