diff options
Diffstat (limited to 'lib/builtins/aarch64/fp_mode.c')
-rw-r--r-- | lib/builtins/aarch64/fp_mode.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/lib/builtins/aarch64/fp_mode.c b/lib/builtins/aarch64/fp_mode.c new file mode 100644 index 000000000..5a413689d --- /dev/null +++ b/lib/builtins/aarch64/fp_mode.c @@ -0,0 +1,59 @@ +//===----- lib/aarch64/fp_mode.c - Floaing-point mode utilities ---*- C -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include <stdint.h> + +#include "../fp_mode.h" + +#define AARCH64_TONEAREST 0x0 +#define AARCH64_UPWARD 0x1 +#define AARCH64_DOWNWARD 0x2 +#define AARCH64_TOWARDZERO 0x3 +#define AARCH64_RMODE_MASK (AARCH64_TONEAREST | AARCH64_UPWARD | \ + AARCH64_DOWNWARD | AARCH64_TOWARDZERO) +#define AARCH64_RMODE_SHIFT 22 + +#define AARCH64_INEXACT 0x10 + +#ifndef __ARM_FP +// For soft float targets, allow changing rounding mode by overriding the weak +// __aarch64_fe_default_rmode symbol. +FE_ROUND_MODE __attribute__((weak)) __aarch64_fe_default_rmode = FE_TONEAREST; +#endif + +FE_ROUND_MODE __fe_getround() { +#ifdef __ARM_FP + uint64_t fpcr; + __asm__ __volatile__("mrs %0, fpcr" : "=r" (fpcr)); + fpcr = fpcr >> AARCH64_RMODE_SHIFT & AARCH64_RMODE_MASK; + switch (fpcr) { + case AARCH64_UPWARD: + return FE_UPWARD; + case AARCH64_DOWNWARD: + return FE_DOWNWARD; + case AARCH64_TOWARDZERO: + return FE_TOWARDZERO; + case AARCH64_TONEAREST: + default: + return FE_TONEAREST; + } +#else + return __aarch64_fe_default_rmode; +#endif +} + +int __fe_raise_inexact() { +#ifdef __ARM_FP + uint64_t fpsr; + __asm__ __volatile__("mrs %0, fpsr" : "=r" (fpsr)); + __asm__ __volatile__("msr fpsr, %0" : : "ri" (fpsr | AARCH64_INEXACT)); + return 0; +#else + return 0; +#endif +} |