riscv64: fenv implementation.
Signed-off-by: Mao Han <han_mao@linux.alibaba.com>
Signed-off-by: Xia Lifang <lifang_xia@linux.alibaba.com>
Signed-off-by: Chen Guoyin <chenguoyin.cgy@linux.alibaba.com>
Signed-off-by: Wang Chen <wangchen20@iscas.ac.cn>
Signed-off-by: Lu Xufan <luxufan@iscas.ac.cn>
Test: treehugger
Change-Id: I0f0227cd4cb5e78aba1a749f8d8fce296a024dfb
diff --git a/libm/riscv64/fenv.c b/libm/riscv64/fenv.c
new file mode 100644
index 0000000..f16e5a9
--- /dev/null
+++ b/libm/riscv64/fenv.c
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <fenv.h>
+#include <stdint.h>
+
+const fenv_t __fe_dfl_env = 0;
+
+int fegetenv(fenv_t* envp) {
+ __asm__ __volatile__("frcsr %0" : "=r"(*envp));
+ return 0;
+}
+
+int fesetenv(const fenv_t* envp) {
+ fenv_t env;
+ fegetenv(&env);
+ if (*envp != env) {
+ __asm__ __volatile__("fscsr %z0" : : "r"(*envp));
+ }
+ return 0;
+}
+
+int feclearexcept(int excepts) {
+ __asm__ __volatile__("csrc fflags, %0" : : "r"(excepts & FE_ALL_EXCEPT));
+ return 0;
+}
+
+int fegetexceptflag(fexcept_t* flagp, int excepts) {
+ *flagp = fetestexcept(excepts & FE_ALL_EXCEPT);
+ return 0;
+}
+
+int fesetexceptflag(const fexcept_t* flagp, int excepts) {
+ feclearexcept((~*flagp) & excepts);
+ feraiseexcept(*flagp & excepts);
+ return 0;
+}
+
+int feraiseexcept(int excepts) {
+ __asm__ __volatile__("csrs fflags, %0" : : "r"(excepts));
+ return 0;
+}
+
+int fetestexcept(int excepts) {
+ int flags;
+ __asm__ __volatile__("frflags %0" : "=r"(flags));
+ return flags & excepts;
+}
+
+int fegetround(void) {
+ int rm;
+ __asm__ __volatile__("frrm %0" : "=r"(rm));
+ return rm;
+}
+
+int fesetround(int round) {
+ if (round < FE_TONEAREST || round > FE_UPWARD) return -1;
+ __asm__ __volatile__("fsrm %z0" : : "r"(round));
+ return 0;
+}
+
+int feholdexcept(fenv_t* envp) {
+ fegetenv(envp);
+ feclearexcept(FE_ALL_EXCEPT);
+ return 0;
+}
+
+int feupdateenv(const fenv_t* envp) {
+ int excepts = fetestexcept(FE_ALL_EXCEPT);
+ fesetenv(envp);
+ feraiseexcept(excepts);
+ return 0;
+}
+
+int feenableexcept(int mask __unused) {
+ return -1;
+}
+
+int fedisableexcept(int mask __unused) {
+ return 0;
+}
+
+int fegetexcept(void) {
+ return 0;
+}