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#define FASTLED_INTERNAL
#include <stdint.h>
#define RAND16_SEED 1337
uint16_t rand16seed = RAND16_SEED;
// memset8, memcpy8, memmove8:
// optimized avr replacements for the standard "C" library
// routines memset, memcpy, and memmove.
//
// There are two techniques that make these routines
// faster than the standard avr-libc routines.
// First, the loops are unrolled 2X, meaning that
// the average loop overhead is cut in half.
// And second, the compare-and-branch at the bottom
// of each loop decrements the low byte of the
// counter, and if the carry is clear, it branches
// back up immediately. Only if the low byte math
// causes carry do we bother to decrement the high
// byte and check that result for carry as well.
// Results for a 100-byte buffer are 20-40% faster
// than standard avr-libc, at a cost of a few extra
// bytes of code.
#if defined(__AVR__)
//__attribute__ ((noinline))
void * memset8 ( void * ptr, uint8_t val, uint16_t num )
{
asm volatile(
" movw r26, %[ptr] \n\t"
" sbrs %A[num], 0 \n\t"
" rjmp Lseteven_%= \n\t"
" rjmp Lsetodd_%= \n\t"
"Lsetloop_%=: \n\t"
" st X+, %[val] \n\t"
"Lsetodd_%=: \n\t"
" st X+, %[val] \n\t"
"Lseteven_%=: \n\t"
" subi %A[num], 2 \n\t"
" brcc Lsetloop_%= \n\t"
" sbci %B[num], 0 \n\t"
" brcc Lsetloop_%= \n\t"
: [num] "+r" (num)
: [ptr] "r" (ptr),
[val] "r" (val)
: "memory"
);
return ptr;
}
//__attribute__ ((noinline))
void * memcpy8 ( void * dst, const void* src, uint16_t num )
{
asm volatile(
" movw r30, %[src] \n\t"
" movw r26, %[dst] \n\t"
" sbrs %A[num], 0 \n\t"
" rjmp Lcpyeven_%= \n\t"
" rjmp Lcpyodd_%= \n\t"
"Lcpyloop_%=: \n\t"
" ld __tmp_reg__, Z+ \n\t"
" st X+, __tmp_reg__ \n\t"
"Lcpyodd_%=: \n\t"
" ld __tmp_reg__, Z+ \n\t"
" st X+, __tmp_reg__ \n\t"
"Lcpyeven_%=: \n\t"
" subi %A[num], 2 \n\t"
" brcc Lcpyloop_%= \n\t"
" sbci %B[num], 0 \n\t"
" brcc Lcpyloop_%= \n\t"
: [num] "+r" (num)
: [src] "r" (src),
[dst] "r" (dst)
: "memory"
);
return dst;
}
//__attribute__ ((noinline))
void * memmove8 ( void * dst, const void* src, uint16_t num )
{
if( src > dst) {
// if src > dst then we can use the forward-stepping memcpy8
return memcpy8( dst, src, num);
} else {
// if src < dst then we have to step backward:
dst = (char*)dst + num;
src = (char*)src + num;
asm volatile(
" movw r30, %[src] \n\t"
" movw r26, %[dst] \n\t"
" sbrs %A[num], 0 \n\t"
" rjmp Lmoveven_%= \n\t"
" rjmp Lmovodd_%= \n\t"
"Lmovloop_%=: \n\t"
" ld __tmp_reg__, -Z \n\t"
" st -X, __tmp_reg__ \n\t"
"Lmovodd_%=: \n\t"
" ld __tmp_reg__, -Z \n\t"
" st -X, __tmp_reg__ \n\t"
"Lmoveven_%=: \n\t"
" subi %A[num], 2 \n\t"
" brcc Lmovloop_%= \n\t"
" sbci %B[num], 0 \n\t"
" brcc Lmovloop_%= \n\t"
: [num] "+r" (num)
: [src] "r" (src),
[dst] "r" (dst)
: "memory"
);
return dst;
}
}
#endif /* AVR */
#if 0
// TEST / VERIFICATION CODE ONLY BELOW THIS POINT
#include <Arduino.h>
#include "lib8tion.h"
void test1abs( int8_t i)
{
Serial.print("abs("); Serial.print(i); Serial.print(") = ");
int8_t j = abs8(i);
Serial.print(j); Serial.println(" ");
}
void testabs()
{
delay(5000);
for( int8_t q = -128; q != 127; q++) {
test1abs(q);
}
for(;;){};
}
void testmul8()
{
delay(5000);
byte r, c;
Serial.println("mul8:");
for( r = 0; r <= 20; r += 1) {
Serial.print(r); Serial.print(" : ");
for( c = 0; c <= 20; c += 1) {
byte t;
t = mul8( r, c);
Serial.print(t); Serial.print(' ');
}
Serial.println(' ');
}
Serial.println("done.");
for(;;){};
}
void testscale8()
{
delay(5000);
byte r, c;
Serial.println("scale8:");
for( r = 0; r <= 240; r += 10) {
Serial.print(r); Serial.print(" : ");
for( c = 0; c <= 240; c += 10) {
byte t;
t = scale8( r, c);
Serial.print(t); Serial.print(' ');
}
Serial.println(' ');
}
Serial.println(' ');
Serial.println("scale8_video:");
for( r = 0; r <= 100; r += 4) {
Serial.print(r); Serial.print(" : ");
for( c = 0; c <= 100; c += 4) {
byte t;
t = scale8_video( r, c);
Serial.print(t); Serial.print(' ');
}
Serial.println(' ');
}
Serial.println("done.");
for(;;){};
}
void testqadd8()
{
delay(5000);
byte r, c;
for( r = 0; r <= 240; r += 10) {
Serial.print(r); Serial.print(" : ");
for( c = 0; c <= 240; c += 10) {
byte t;
t = qadd8( r, c);
Serial.print(t); Serial.print(' ');
}
Serial.println(' ');
}
Serial.println("done.");
for(;;){};
}
void testnscale8x3()
{
delay(5000);
byte r, g, b, sc;
for( byte z = 0; z < 10; z++) {
r = random8(); g = random8(); b = random8(); sc = random8();
Serial.print("nscale8x3_video( ");
Serial.print(r); Serial.print(", ");
Serial.print(g); Serial.print(", ");
Serial.print(b); Serial.print(", ");
Serial.print(sc); Serial.print(") = [ ");
nscale8x3_video( r, g, b, sc);
Serial.print(r); Serial.print(", ");
Serial.print(g); Serial.print(", ");
Serial.print(b); Serial.print("]");
Serial.println(' ');
}
Serial.println("done.");
for(;;){};
}
#endif
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