From 3f8d9d58c59fdbe27301d0e18bfd426a5f2edf19 Mon Sep 17 00:00:00 2001 From: Wilco Dijkstra Date: Fri, 9 Feb 2018 16:59:23 +0000 Subject: [AArch64] Use builtins for fpcr/fpsr Since GCC has support for accessing FPSR/FPCR, use them when possible so that the asm instructions can be removed eventually. Although GCC 5 supports the builtins, it has an optimization bug, so use them from GCC 6 onwards. * sysdeps/aarch64/fpu/fpu_control.h: Use builtins for accessing FPCR/FPSR. --- ChangeLog | 5 +++++ sysdeps/aarch64/fpu/fpu_control.h | 15 +++++++++++---- 2 files changed, 16 insertions(+), 4 deletions(-) diff --git a/ChangeLog b/ChangeLog index 041f38ef6d..385e8667b8 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2018-02-09 Wilco Dijkstra + + * sysdeps/aarch64/fpu/fpu_control.h: Use builtins for accessing + FPCR/FPSR. + 2018-02-09 Rical Jasan * manual/creature.texi: Convert references to gcc.info to gcc. diff --git a/sysdeps/aarch64/fpu/fpu_control.h b/sysdeps/aarch64/fpu/fpu_control.h index 570e3dca78..d0cc5afc9f 100644 --- a/sysdeps/aarch64/fpu/fpu_control.h +++ b/sysdeps/aarch64/fpu/fpu_control.h @@ -21,17 +21,24 @@ /* Macros for accessing the FPCR and FPSR. */ -#define _FPU_GETCW(fpcr) \ +#if __GNUC_PREREQ (6,0) +# define _FPU_GETCW(fpcr) (fpcr = __builtin_aarch64_get_fpcr ()) +# define _FPU_SETCW(fpcr) __builtin_aarch64_set_fpcr (fpcr) +# define _FPU_GETFPSR(fpsr) (fpsr = __builtin_aarch64_get_fpsr ()) +# define _FPU_SETFPSR(fpsr) __builtin_aarch64_set_fpsr (fpsr) +#else +# define _FPU_GETCW(fpcr) \ __asm__ __volatile__ ("mrs %0, fpcr" : "=r" (fpcr)) -#define _FPU_SETCW(fpcr) \ +# define _FPU_SETCW(fpcr) \ __asm__ __volatile__ ("msr fpcr, %0" : : "r" (fpcr)) -#define _FPU_GETFPSR(fpsr) \ +# define _FPU_GETFPSR(fpsr) \ __asm__ __volatile__ ("mrs %0, fpsr" : "=r" (fpsr)) -#define _FPU_SETFPSR(fpsr) \ +# define _FPU_SETFPSR(fpsr) \ __asm__ __volatile__ ("msr fpsr, %0" : : "r" (fpsr)) +#endif /* Reserved bits should be preserved when modifying register contents. These two masks indicate which bits in each of FPCR and -- cgit v1.2.3