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#include <stdarg.h>
extern long time();
extern long insn();
extern char *malloc();
extern void *memcpy(char *dest, const char *src, int n);
extern char *strcpy(char *dest, const char *src);
extern int strcmp(const char *s1, const char *s2);
extern int printf(const char *format, ...);
extern int scanf(const char *format, ...);
char heap_memory[1024];
int heap_memory_used = 0;
long time()
{
int cycles;
asm("rdcycle %0" : "=r"(cycles));
// printf("[time() -> %d]", cycles);
return cycles;
}
long insn()
{
int insns;
asm("rdinstret %0" : "=r"(insns));
// printf("[insn() -> %d]", insns);
return insns;
}
char *malloc(int size)
{
char *p = heap_memory + heap_memory_used;
// printf("[malloc(%d) -> %d (%d..%d)]", size, (int)p, heap_memory_used, heap_memory_used + size);
heap_memory_used += size;
if (heap_memory_used > 1024)
asm("sbreak");
return p;
}
#if 0
void *memcpy(char *dest, const char *src, int n)
{
while (n--)
*(dest++) = *(src++);
}
#else
/* copy&paste from disassembled libc */
asm (
" .global memcpy; "
" memcpy: xor a5,a1,a0; "
" slli a4,a5,0x1e; "
" add a7,a0,a2; "
" bnez a4,.M1; "
" li a5,3; "
" bleu a2,a5,.M2; "
" slli a5,a0,0x1e; "
" bnez a5,.M3; "
" andi a6,a7,-4; "
" addi a5,a6,-32; "
" mv a4,a0; "
" bltu a0,a5,.M4; "
" .M9: mv a3,a1; "
" mv a5,a4; "
" bleu a6,a4,.M5; "
" .M6: lw a2,0(a3); "
" addi a5,a5,4; "
" addi a3,a3,4; "
" sw a2,-4(a5); "
" bltu a5,a6,.M6; "
" not a5,a4; "
" add a6,a5,a6; "
" andi a6,a6,-4; "
" addi a6,a6,4; "
" add a4,a4,a6; "
" add a1,a1,a6; "
" .M5: bltu a4,a7,.M7; "
" .M11: ret; "
" .M3: mv a4,a0; "
" .M8: lbu a5,0(a1); "
" addi a4,a4,1; "
" addi a1,a1,1; "
" sb a5,-1(a4); "
" slli a5,a4,0x1e; "
" bnez a5,.M8; "
" andi a6,a7,-4; "
" addi a5,a6,-32; "
" bleu a5,a4,.M9; "
" .M4: lw t6,0(a1); "
" lw t5,4(a1); "
" lw t4,8(a1); "
" lw t3,12(a1); "
" lw t2,16(a1); "
" lw t1,20(a1); "
" lw t0,24(a1); "
" lw a2,28(a1); "
" addi a1,a1,36; "
" addi a4,a4,36; "
" lw a3,-4(a1); "
" sw t6,-36(a4); "
" sw t5,-32(a4); "
" sw t4,-28(a4); "
" sw t3,-24(a4); "
" sw t2,-20(a4); "
" sw t1,-16(a4); "
" sw t0,-12(a4); "
" sw a2,-8(a4); "
" sw a3,-4(a4); "
" bltu a4,a5,.M4; "
" j .M9; "
" .M1: mv a4,a0; "
" bleu a7,a0,.M10; "
" .M7: lbu a5,0(a1); "
" addi a4,a4,1; "
" addi a1,a1,1; "
" sb a5,-1(a4); "
" bltu a4,a7,.M7; "
" .M12: ret; "
" .M2: mv a4,a0; "
" bleu a7,a0,.M11; "
" lbu a5,0(a1); "
" addi a4,a4,1; "
" addi a1,a1,1; "
" sb a5,-1(a4); "
" bltu a4,a7,.M7; "
" j .M12; "
" .M10: ret; "
);
#endif
#if 0
char *strcpy(char *dest, const char *src)
{
char *ret = dest;
// printf("[strcpy()]");
do
*(dest++) = *src;
while (*(src++));
return ret;
}
#else
/* copy&paste from disassembled libc */
asm (
" .global strcpy; "
" strcpy: or a5,a0,a1; "
" slli a4,a5,0x1e; "
" bnez a4,.S1; "
" lw a4,0(a1); "
" lui a3,0x7f7f8; "
" addi a3,a3,-129; "
" and a5,a4,a3; "
" add a5,a5,a3; "
" or a7,a4,a3; "
" or a7,a7,a5; "
" li a5,-1; "
" mv a2,a0; "
" bne a7,a5,.S2; "
" .S3: addi a2,a2,4; "
" addi a1,a1,4; "
" sw a4,-4(a2); "
" lw a4,0(a1); "
" and a5,a4,a3; "
" or a6,a4,a3; "
" add a5,a5,a3; "
" or a5,a6,a5; "
" beq a5,a7,.S3; "
" .S2: lbu a5,0(a1); "
" lbu a4,1(a1); "
" lbu a3,2(a1); "
" sb a5,0(a2); "
" beqz a5,.S4; "
" sb a4,1(a2); "
" beqz a4,.S4; "
" sb a3,2(a2); "
" bnez a3,.S5; "
" .S4: ret; "
" .S5: sb zero,3(a2); "
" ret; "
" .S1: mv a5,a0; "
" .S6: lbu a4,0(a1); "
" addi a5,a5,1; "
" addi a1,a1,1; "
" sb a4,-1(a5); "
" bnez a4,.S6; "
" ret; "
);
#endif
#if 0
int strcmp(const char *s1, const char *s2)
{
// printf("[strcmp()]");
while (1) {
if (*s1 == 0 && *s2 == 0)
return 0;
if (*s1 < *s2)
return -1;
if (*s1 > *s2)
return +1;
s1++, s2++;
}
}
#else
/* copy&paste from disassembled libc */
asm (
" .global strcmp; "
" strcmp: or a4,a0,a1; "
" li t2,-1; "
" andi a4,a4,3; "
" bnez a4,.K1; "
" lui t3,0x7f7f8; "
" addi t3,t3,-129; "
" .K6: lw a2,0(a0); "
" lw a3,0(a1); "
" and t0,a2,t3; "
" or t1,a2,t3; "
" add t0,t0,t3; "
" or t0,t0,t1; "
" bne t0,t2,.K2; "
" bne a2,a3,.K3; "
" lw a2,4(a0); "
" lw a3,4(a1); "
" and t0,a2,t3; "
" or t1,a2,t3; "
" add t0,t0,t3; "
" or t0,t0,t1; "
" bne t0,t2,.K4; "
" bne a2,a3,.K3; "
" lw a2,8(a0); "
" lw a3,8(a1); "
" and t0,a2,t3; "
" or t1,a2,t3; "
" add t0,t0,t3; "
" or t0,t0,t1; "
" bne t0,t2,.K5; "
" addi a0,a0,12; "
" addi a1,a1,12; "
" beq a2,a3,.K6; "
" .K3: slli a4,a2,0x10; "
" slli a5,a3,0x10; "
" bne a4,a5,.K7; "
" srli a4,a2,0x10; "
" srli a5,a3,0x10; "
" sub a0,a4,a5; "
" andi a1,a0,255; "
" bnez a1,.K8; "
" ret; "
" .K7: srli a4,a4,0x10; "
" srli a5,a5,0x10; "
" sub a0,a4,a5; "
" andi a1,a0,255; "
" bnez a1,.K8; "
" ret; "
" .K8: andi a4,a4,255; "
" andi a5,a5,255; "
" sub a0,a4,a5; "
" ret; "
" .K1: lbu a2,0(a0); "
" lbu a3,0(a1); "
" addi a0,a0,1; "
" addi a1,a1,1; "
" bne a2,a3,.K9; "
" bnez a2,.K1; "
" .K9: sub a0,a2,a3; "
" ret; "
" .K4: addi a0,a0,4; "
" addi a1,a1,4; "
" .K2: bne a2,a3,.K1; "
" li a0,0; "
" ret; "
" .K5: addi a0,a0,8; "
" addi a1,a1,8; "
" bne a2,a3,.K1; "
" li a0,0; "
" ret; "
);
#endif
static void printf_c(int c)
{
*((volatile int*)0x10000000) = c;
}
static void printf_s(char *p)
{
while (*p)
*((volatile int*)0x10000000) = *(p++);
}
static void printf_d(int val)
{
char buffer[32];
char *p = buffer;
if (val < 0) {
printf_c('-');
val = -val;
}
while (val || p == buffer) {
*(p++) = '0' + val % 10;
val = val / 10;
}
while (p != buffer)
printf_c(*(--p));
}
int printf(const char *format, ...)
{
int i;
va_list ap;
va_start(ap, format);
for (i = 0; format[i]; i++)
if (format[i] == '%') {
while (format[++i]) {
if (format[i] == 'c') {
printf_c(va_arg(ap,int));
break;
}
if (format[i] == 's') {
printf_s(va_arg(ap,char*));
break;
}
if (format[i] == 'd') {
printf_d(va_arg(ap,int));
break;
}
}
} else
printf_c(format[i]);
va_end(ap);
}
int scanf(const char *format, ...)
{
// printf("[scanf(\"%s\")]\n", format);
va_list ap;
va_start(ap, format);
*va_arg(ap,int*) = 100;
va_end(ap);
return 0;
}
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