libm/riscv: Fix machine-specific sqrt build process

Like ARM, some RISC-V implementations have hardware sqrt. Support for
that can be detected at compile time, which the code did. However, the
filenames were incorrect so that both the risc-v specific and general
code were getting included in the resulting library.

Fix this by following the ARM model and #include'ing the general code
when the architecture-specific support is not available.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/newlib/libm/machine/riscv/ef_sqrt.c b/newlib/libm/machine/riscv/ef_sqrt.c
new file mode 100644
index 000000000..1f378f547
--- /dev/null
+++ b/newlib/libm/machine/riscv/ef_sqrt.c
@@ -0,0 +1,51 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright © 2020 Keith Packard
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. 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.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * 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 HOLDER 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 <math.h>
+#include "math_config.h"
+
+#if defined(__riscv_fsqrt) && __riscv_flen >= 32
+
+float
+__ieee754_sqrtf (float x)
+{
+	float result;
+	asm ("fsqrt.s %0, %1" : "=f" (result) : "f" (x));
+	return result;
+}
+
+#else
+#include "../../math/ef_sqrt.c"
+#endif