From d982368bec9638619a6dfcaf9242896661695353 Mon Sep 17 00:00:00 2001 From: Elliot Saba Date: Sun, 15 Jan 2017 14:42:28 -0800 Subject: [PATCH] Fix `arm` floating-point status register code * Use an actual compiler definition to determine whether we have a floating-point unit or not. * Use a modern (VFPU) assembly instruction to get/set the fpsr * If we don't have an fpsr, at least zero out the return value --- include/openlibm_fenv_arm.h | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/include/openlibm_fenv_arm.h b/include/openlibm_fenv_arm.h index 8ada694..ff1946f 100644 --- a/include/openlibm_fenv_arm.h +++ b/include/openlibm_fenv_arm.h @@ -69,11 +69,13 @@ extern const fenv_t __fe_dfl_env; #if defined(__aarch64__) #define __rfs(__fpsr) __asm __volatile("mrs %0,fpsr" : "=r" (*(__fpsr))) #define __wfs(__fpsr) __asm __volatile("msr fpsr,%0" : : "r" (__fpsr)) -#elif defined(ARM_HARD_FLOAT) -#define __rfs(__fpsr) __asm __volatile("rfs %0" : "=r" (*(__fpsr))) -#define __wfs(__fpsr) __asm __volatile("wfs %0" : : "r" (__fpsr)) +/* Test for hardware support for ARM floating point operations, explicitly +checking for float and double support, see "ARM C Language Extensions", 6.5.1 */ +#elif defined(__ARM_FP) && (__ARM_FP & 0x0C) != 0 +#define __rfs(__fpsr) __asm __volatile("vmrs %0,fpscr" : "=&r" (*(__fpsr))) +#define __wfs(__fpsr) __asm __volatile("vmsr fpscr,%0" : : "r" (__fpsr)) #else -#define __rfs(__fpsr) +#define __rfs(__fpsr) (*(__fpsr) = 0) #define __wfs(__fpsr) #endif