168d75effSDimitry Andric //===----- lib/aarch64/fp_mode.c - Floaing-point mode utilities ---*- C -*-===// 268d75effSDimitry Andric // 368d75effSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 468d75effSDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 568d75effSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 668d75effSDimitry Andric // 768d75effSDimitry Andric //===----------------------------------------------------------------------===// 868d75effSDimitry Andric 968d75effSDimitry Andric #include <stdint.h> 1068d75effSDimitry Andric 1168d75effSDimitry Andric #include "../fp_mode.h" 1268d75effSDimitry Andric 1368d75effSDimitry Andric #define AARCH64_TONEAREST 0x0 1468d75effSDimitry Andric #define AARCH64_UPWARD 0x1 1568d75effSDimitry Andric #define AARCH64_DOWNWARD 0x2 1668d75effSDimitry Andric #define AARCH64_TOWARDZERO 0x3 1768d75effSDimitry Andric #define AARCH64_RMODE_MASK (AARCH64_TONEAREST | AARCH64_UPWARD | \ 1868d75effSDimitry Andric AARCH64_DOWNWARD | AARCH64_TOWARDZERO) 1968d75effSDimitry Andric #define AARCH64_RMODE_SHIFT 22 2068d75effSDimitry Andric 2168d75effSDimitry Andric #define AARCH64_INEXACT 0x10 2268d75effSDimitry Andric 2368d75effSDimitry Andric #ifndef __ARM_FP 2468d75effSDimitry Andric // For soft float targets, allow changing rounding mode by overriding the weak 2568d75effSDimitry Andric // __aarch64_fe_default_rmode symbol. 26fe6060f1SDimitry Andric CRT_FE_ROUND_MODE __attribute__((weak)) __aarch64_fe_default_rmode = 27fe6060f1SDimitry Andric CRT_FE_TONEAREST; 2868d75effSDimitry Andric #endif 2968d75effSDimitry Andric __fe_getround(void)30*81ad6265SDimitry AndricCRT_FE_ROUND_MODE __fe_getround(void) { 3168d75effSDimitry Andric #ifdef __ARM_FP 3268d75effSDimitry Andric uint64_t fpcr; 3368d75effSDimitry Andric __asm__ __volatile__("mrs %0, fpcr" : "=r" (fpcr)); 3468d75effSDimitry Andric fpcr = fpcr >> AARCH64_RMODE_SHIFT & AARCH64_RMODE_MASK; 3568d75effSDimitry Andric switch (fpcr) { 3668d75effSDimitry Andric case AARCH64_UPWARD: 37fe6060f1SDimitry Andric return CRT_FE_UPWARD; 3868d75effSDimitry Andric case AARCH64_DOWNWARD: 39fe6060f1SDimitry Andric return CRT_FE_DOWNWARD; 4068d75effSDimitry Andric case AARCH64_TOWARDZERO: 41fe6060f1SDimitry Andric return CRT_FE_TOWARDZERO; 4268d75effSDimitry Andric case AARCH64_TONEAREST: 4368d75effSDimitry Andric default: 44fe6060f1SDimitry Andric return CRT_FE_TONEAREST; 4568d75effSDimitry Andric } 4668d75effSDimitry Andric #else 4768d75effSDimitry Andric return __aarch64_fe_default_rmode; 4868d75effSDimitry Andric #endif 4968d75effSDimitry Andric } 5068d75effSDimitry Andric __fe_raise_inexact(void)51*81ad6265SDimitry Andricint __fe_raise_inexact(void) { 5268d75effSDimitry Andric #ifdef __ARM_FP 5368d75effSDimitry Andric uint64_t fpsr; 5468d75effSDimitry Andric __asm__ __volatile__("mrs %0, fpsr" : "=r" (fpsr)); 5568d75effSDimitry Andric __asm__ __volatile__("msr fpsr, %0" : : "ri" (fpsr | AARCH64_INEXACT)); 5668d75effSDimitry Andric return 0; 5768d75effSDimitry Andric #else 5868d75effSDimitry Andric return 0; 5968d75effSDimitry Andric #endif 6068d75effSDimitry Andric } 61