Added hypotf and hypotl implementations

Author: ZERICO2005

src/libc/hypot.c

@@ -0,0 +1,35 @@
+#include <math.h>
+#include <stdint.h>
+
+typedef union F32_pun {
+    float flt;
+    uint32_t bin;
+} F32_pun;
+
+float hypotf(float arg_x, float arg_y) {
+    F32_pun x, y;
+    x.flt = fabsf(arg_x);
+    y.flt = fabsf(arg_y);
+    if (x.bin < y.bin) {
+        float temp = x.flt;
+        x.flt = y.flt;
+        y.flt = temp;
+    }
+    // x >= y, or x is NaN
+    if (isfinite(x.flt)) {
+        int expon;
+        // scale the arguments to prevent overflow/underflow
+        x.flt = frexpf(x.flt, &expon);
+        y.flt = ldexpf(y.flt, -expon);
+        float ret = sqrtf(x.flt * x.flt + y.flt * y.flt);
+        return ldexpf(ret, expon);
+    }
+    if (isinf(y.flt)) {
+        // return infinity, even if the other argument is NaN
+        return y.flt;
+    }
+    // x is infinity/NaN
+    return x.flt;
+}
+
+double hypot(double, double) __attribute__((alias("hypotf")));

src/libc/hypotf.c

@@ -0,0 +1,33 @@
+#include <math.h>
+#include <stdint.h>
+
+typedef union F64_pun {
+    long double flt;
+    uint64_t bin;
+} F64_pun;
+
+long double hypotl(long double arg_x, long double arg_y) {
+    F64_pun x, y;
+    x.flt = fabsl(arg_x);
+    y.flt = fabsl(arg_y);
+    if (x.bin < y.bin) {
+        long double temp = x.flt;
+        x.flt = y.flt;
+        y.flt = temp;
+    }
+    // x >= y, or x is NaN
+    if (isfinite(x.flt)) {
+        int expon;
+        // scale the arguments to prevent overflow/underflow
+        x.flt = frexpl(x.flt, &expon);
+        y.flt = ldexpl(y.flt, -expon);
+        long double ret = sqrtl(x.flt * x.flt + y.flt * y.flt);
+        return ldexpl(ret, expon);
+    }
+    if (isinf(y.flt)) {
+        // return infinity, even if the other argument is NaN
+        return y.flt;
+    }
+    // x is infinity/NaN
+    return x.flt;
+}