1 files changed, 205 insertions, 0 deletions
diff --git a/src/common/int-util.h b/src/common/int-util.h
new file mode 100644
index 000000000..ad0ef60e0
--- /dev/null
+++ b/src/common/int-util.h
@@ -0,0 +1,205 @@
+// Copyright (c) 2012-2013 The Cryptonote developers
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#pragma once
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/param.h>
+
+#if defined(_MSC_VER)
+#include <stdlib.h>
+
+static inline uint32_t rol32(uint32_t x, int r) {
+  static_assert(sizeof(uint32_t) == sizeof(unsigned int), "this code assumes 32-bit integers");
+  return _rotl(x, r);
+}
+
+static inline uint64_t rol64(uint64_t x, int r) {
+  return _rotl64(x, r);
+}
+
+#else
+
+static inline uint32_t rol32(uint32_t x, int r) {
+  return (x << (r & 31)) | (x >> (-r & 31));
+}
+
+static inline uint64_t rol64(uint64_t x, int r) {
+  return (x << (r & 63)) | (x >> (-r & 63));
+}
+
+#endif
+
+inline uint64_t hi_dword(uint64_t val) {
+  return val >> 32;
+}
+
+inline uint64_t lo_dword(uint64_t val) {
+  return val & 0xFFFFFFFF;
+}
+
+inline uint64_t mul128(uint64_t multiplier, uint64_t multiplicand, uint64_t* product_hi) {
+  // multiplier   = ab = a * 2^32 + b
+  // multiplicand = cd = c * 2^32 + d
+  // ab * cd = a * c * 2^64 + (a * d + b * c) * 2^32 + b * d
+  uint64_t a = hi_dword(multiplier);
+  uint64_t b = lo_dword(multiplier);
+  uint64_t c = hi_dword(multiplicand);
+  uint64_t d = lo_dword(multiplicand);
+
+  uint64_t ac = a * c;
+  uint64_t ad = a * d;
+  uint64_t bc = b * c;
+  uint64_t bd = b * d;
+
+  uint64_t adbc = ad + bc;
+  uint64_t adbc_carry = adbc < ad ? 1 : 0;
+
+  // multiplier * multiplicand = product_hi * 2^64 + product_lo
+  uint64_t product_lo = bd + (adbc << 32);
+  uint64_t product_lo_carry = product_lo < bd ? 1 : 0;
+  *product_hi = ac + (adbc >> 32) + (adbc_carry << 32) + product_lo_carry;
+  assert(ac <= *product_hi);
+
+  return product_lo;
+}
+
+inline uint64_t div_with_reminder(uint64_t dividend, uint32_t divisor, uint32_t* remainder) {
+  dividend |= ((uint64_t)*remainder) << 32;
+  *remainder = dividend % divisor;
+  return dividend / divisor;
+}
+
+// Long division with 2^32 base
+inline uint32_t div128_32(uint64_t dividend_hi, uint64_t dividend_lo, uint32_t divisor, uint64_t* quotient_hi, uint64_t* quotient_lo) {
+  uint64_t dividend_dwords[4];
+  uint32_t remainder = 0;
+
+  dividend_dwords[3] = hi_dword(dividend_hi);
+  dividend_dwords[2] = lo_dword(dividend_hi);
+  dividend_dwords[1] = hi_dword(dividend_lo);
+  dividend_dwords[0] = lo_dword(dividend_lo);
+
+  *quotient_hi  = div_with_reminder(dividend_dwords[3], divisor, &remainder) << 32;
+  *quotient_hi |= div_with_reminder(dividend_dwords[2], divisor, &remainder);
+  *quotient_lo  = div_with_reminder(dividend_dwords[1], divisor, &remainder) << 32;
+  *quotient_lo |= div_with_reminder(dividend_dwords[0], divisor, &remainder);
+
+  return remainder;
+}
+
+#define IDENT32(x) ((uint32_t) (x))
+#define IDENT64(x) ((uint64_t) (x))
+
+#define SWAP32(x) ((((uint32_t) (x) & 0x000000ff) << 24) | \
+  (((uint32_t) (x) & 0x0000ff00) <<  8) | \
+  (((uint32_t) (x) & 0x00ff0000) >>  8) | \
+  (((uint32_t) (x) & 0xff000000) >> 24))
+#define SWAP64(x) ((((uint64_t) (x) & 0x00000000000000ff) << 56) | \
+  (((uint64_t) (x) & 0x000000000000ff00) << 40) | \
+  (((uint64_t) (x) & 0x0000000000ff0000) << 24) | \
+  (((uint64_t) (x) & 0x00000000ff000000) <<  8) | \
+  (((uint64_t) (x) & 0x000000ff00000000) >>  8) | \
+  (((uint64_t) (x) & 0x0000ff0000000000) >> 24) | \
+  (((uint64_t) (x) & 0x00ff000000000000) >> 40) | \
+  (((uint64_t) (x) & 0xff00000000000000) >> 56))
+
+static inline uint32_t ident32(uint32_t x) { return x; }
+static inline uint64_t ident64(uint64_t x) { return x; }
+
+static inline uint32_t swap32(uint32_t x) {
+  x = ((x & 0x00ff00ff) << 8) | ((x & 0xff00ff00) >> 8);
+  return (x << 16) | (x >> 16);
+}
+static inline uint64_t swap64(uint64_t x) {
+  x = ((x & 0x00ff00ff00ff00ff) <<  8) | ((x & 0xff00ff00ff00ff00) >>  8);
+  x = ((x & 0x0000ffff0000ffff) << 16) | ((x & 0xffff0000ffff0000) >> 16);
+  return (x << 32) | (x >> 32);
+}
+
+#if defined(__GNUC__)
+#define UNUSED __attribute__((unused))
+#else
+#define UNUSED
+#endif
+static inline void mem_inplace_ident(void *mem UNUSED, size_t n UNUSED) { }
+#undef UNUSED
+
+static inline void mem_inplace_swap32(void *mem, size_t n) {
+  size_t i;
+  for (i = 0; i < n; i++) {
+    ((uint32_t *) mem)[i] = swap32(((const uint32_t *) mem)[i]);
+  }
+}
+static inline void mem_inplace_swap64(void *mem, size_t n) {
+  size_t i;
+  for (i = 0; i < n; i++) {
+    ((uint64_t *) mem)[i] = swap64(((const uint64_t *) mem)[i]);
+  }
+}
+
+static inline void memcpy_ident32(void *dst, const void *src, size_t n) {
+  memcpy(dst, src, 4 * n);
+}
+static inline void memcpy_ident64(void *dst, const void *src, size_t n) {
+  memcpy(dst, src, 8 * n);
+}
+
+static inline void memcpy_swap32(void *dst, const void *src, size_t n) {
+  size_t i;
+  for (i = 0; i < n; i++) {
+    ((uint32_t *) dst)[i] = swap32(((const uint32_t *) src)[i]);
+  }
+}
+static inline void memcpy_swap64(void *dst, const void *src, size_t n) {
+  size_t i;
+  for (i = 0; i < n; i++) {
+    ((uint64_t *) dst)[i] = swap64(((const uint64_t *) src)[i]);
+  }
+}
+
+#if !defined(BYTE_ORDER) || !defined(LITTLE_ENDIAN) || !defined(BIG_ENDIAN)
+static_assert(false, "BYTE_ORDER is undefined. Perhaps, GNU extensions are not enabled");
+#endif
+
+#if BYTE_ORDER == LITTLE_ENDIAN
+#define SWAP32LE IDENT32
+#define SWAP32BE SWAP32
+#define swap32le ident32
+#define swap32be swap32
+#define mem_inplace_swap32le mem_inplace_ident
+#define mem_inplace_swap32be mem_inplace_swap32
+#define memcpy_swap32le memcpy_ident32
+#define memcpy_swap32be memcpy_swap32
+#define SWAP64LE IDENT64
+#define SWAP64BE SWAP64
+#define swap64le ident64
+#define swap64be swap64
+#define mem_inplace_swap64le mem_inplace_ident
+#define mem_inplace_swap64be mem_inplace_swap64
+#define memcpy_swap64le memcpy_ident64
+#define memcpy_swap64be memcpy_swap64
+#endif
+
+#if BYTE_ORDER == BIG_ENDIAN
+#define SWAP32BE IDENT32
+#define SWAP32LE SWAP32
+#define swap32be ident32
+#define swap32le swap32
+#define mem_inplace_swap32be mem_inplace_ident
+#define mem_inplace_swap32le mem_inplace_swap32
+#define memcpy_swap32be memcpy_ident32
+#define memcpy_swap32le memcpy_swap32
+#define SWAP64BE IDENT64
+#define SWAP64LE SWAP64
+#define swap64be ident64
+#define swap64le swap64
+#define mem_inplace_swap64be mem_inplace_ident
+#define mem_inplace_swap64le mem_inplace_swap64
+#define memcpy_swap64be memcpy_ident64
+#define memcpy_swap64le memcpy_swap64
+#endif