fw/memcpy.c (c89d999) - mips_sys · BlinkenArea

memcpy.c

#include "memcpy.h"

/**
 * @brief copy memory
 * @param[in] dest pointer to destination buffer
 * @param[in] src pointer to source data
 * @param[in] sz size of data to copy
 */
void memcpy(void *dest, const void *src, unsigned int sz)
{
  unsigned int *dest4;
  const unsigned int *src4;
  unsigned int sz4;
  unsigned char *dest1;
  const unsigned char *src1;

// word aligned memory addresses -> fast copy
  if (((unsigned int)dest & 3) == 0 && ((unsigned int)src & 3) == 0) {
    dest4 = dest;
    src4 = src;
    sz4 = sz >> 2;
    for ( ; sz4 > 0; --sz4)
      *dest4++ = *src4++;
    // there might still be a few bytes to copy now
    dest = dest4;
    src = src4;
    sz &= 3;
  }

// safe and slow fallback: copy byte-wise
  dest1 = dest;
  src1 = src;
  for ( ; sz > 0; --sz)
    *dest1++ = *src1++;
}

/**
 * @brief set memory to fixed value
 * @param[in] dest pointer to destination buffer
 * @param[in] val fixed value to fill memory with
 * @param[in] sz size of memory to fill
 */
void memset(void *dest, int val, unsigned int sz)
{
  unsigned char val1;
  unsigned int *dest4;
  unsigned int val4;
  unsigned int sz4;
  unsigned char *dest1;

val1 = val;

// word aligned memory address -> fast fill
  if (((unsigned int)dest & 3) == 0) {
    dest4 = dest;
    val4 = val1;
    val4 |= val4 << 8;
    val4 |= val4 << 16;
    sz4 = sz >> 2;
    for ( ; sz4 > 0; --sz4)
      *dest4++ = val4;
    // there might still be a few bytes to fill now
    dest = dest4;
    sz &= 3;
  }

// safe and slow fallback: fill byte-wise
  dest1 = dest;
  for ( ; sz > 0; --sz)
    *dest1++ = val1;
}

mips_sys

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