Add exess from git@gitlab.com:drobilla/exess.git 4638b1f

1 files changed, 72 insertions, 0 deletions

diff --git a/subprojects/exess/src/int_math.h b/subprojects/exess/src/int_math.h
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+++ b/subprojects/exess/src/int_math.h
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+/*
+  Copyright 2019-2021 David Robillard <d@drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#ifndef EXESS_INTMATH_H
+#define EXESS_INTMATH_H
+
+#include "attributes.h"
+
+#include <stdint.h>
+
+static const int uint64_digits10 = 19;
+
+static const uint64_t POW10[] = {1ull,
+                                 10ull,
+                                 100ull,
+                                 1000ull,
+                                 10000ull,
+                                 100000ull,
+                                 1000000ull,
+                                 10000000ull,
+                                 100000000ull,
+                                 1000000000ull,
+                                 10000000000ull,
+                                 100000000000ull,
+                                 1000000000000ull,
+                                 10000000000000ull,
+                                 100000000000000ull,
+                                 1000000000000000ull,
+                                 10000000000000000ull,
+                                 100000000000000000ull,
+                                 1000000000000000000ull,
+                                 10000000000000000000ull};
+
+/// Return the number of leading zeros in `i`
+EXESS_I_CONST_FUNC
+unsigned
+exess_clz32(uint32_t i);
+
+/// Return the number of leading zeros in `i`
+EXESS_I_CONST_FUNC
+unsigned
+exess_clz64(uint64_t i);
+
+/// Return the log base 2 of `i`
+EXESS_I_CONST_FUNC
+uint64_t
+exess_ilog2(uint64_t i);
+
+/// Return the log base 10 of `i`
+EXESS_I_CONST_FUNC
+uint64_t
+exess_ilog10(uint64_t i);
+
+/// Return the number of decimal digits required to represent `i`
+EXESS_I_CONST_FUNC
+uint8_t
+exess_num_digits(uint64_t i);
+
+#endif // EXESS_INTMATH_H