Changeset 516e780 in mainline for uspace/lib/math/generic/__signbit.c

Timestamp:

2018-08-31T11:55:41Z (6 years ago)

Author:

GitHub <noreply@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

fa86fff

Parents:

7f7d642

git-author:

Jiří Zárevúcky <zarevucky.jiri@…> (2018-08-31 11:55:41)

git-committer:

GitHub <noreply@…> (2018-08-31 11:55:41)

Message:

Strip down libmath. (#45)

libmath is mostly unused (except for trunc(), sin() and cos()), and most functions in it are either very imprecise or downright broken. Additionally, it is implemented in manner that conflicts with C standard. Instead of trying to fix all the shortcomings while maintaining unused functionality, I'm opting to simply remove most of it and only keep the parts that are currently necessary.

Later readdition of the removed functions is possible, but there needs to be a reliable way to evaluate their quality first.

File:

• uspace/lib/math/generic/__signbit.c (moved) (moved from uspace/lib/math/generic/tan.c ) (2 diffs)

uspace/lib/math/generic/__signbit.c

@@ -1 +1 @@
 /*
- * Copyright (c) 2015 Jiri Svoboda
+ * Copyright (c) 2018 CZ.NIC, z.s.p.o.
  * All rights reserved.
  *
@@ -27 +27 @@
  */
 
-/** @addtogroup libmath
- * @{
+#include <math.h>
+#include <stdarg.h>
+
+/**
+ * Fallback symbol used when code including <math.h> is compiled with something
+ * other than GCC or Clang. The function itself must be built with GCC or Clang.
  */
-/** @file
- */
+int __signbit(size_t sz, ...)
+{
+        va_list ap;
+        va_start(ap, sz);
 
-#include <math.h>
-#include <tan.h>
+        int result;
 
-/** Tangent (32-bit floating point)
- *
- * Compute tangent value.
- *
- * @param arg Tangent argument.
- *
- * @return Tangent value.
- *
- */
-float32_t float32_tan(float32_t arg)
-{
-        return sin_f32(arg) / cos_f32(arg);
+        switch (sz) {
+        case 4:
+                result = signbit(va_arg(ap, double));
+                break;
+        case 8:
+                result = signbit(va_arg(ap, double));
+                break;
+        default:
+                result = signbit(va_arg(ap, long double));
+                break;
+        }
+
+        va_end(ap);
+        return result;
 }
 
-/** Sine (64-bit floating point)
- *
- * Compute sine value.
- *
- * @param arg Sine argument.
- *
- * @return Sine value.
- *
- */
-float64_t float64_tan(float64_t arg)
-{
-        return sin_f64(arg) / cos_f64(arg);
-}
-
-
-/** @}
- */