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#include <stdio.h>
#include <inttypes.h>
#include "../deps/ejit/include/ejit/ejit.h"
static struct ejit_func *compile(const char *program)
{
struct ejit_func *func = ejit_create_func(EJIT_INT32, 0, NULL);
if (!func) {
fprintf(stderr, "failed allocating func\n");
return NULL;
}
/* initialize accumulator */
ejit_movi(func, EJIT_GPR(0), 0);
/* load constant 2 into register for multiplication/division since ejit
* doesn't have muli/divi instructions */
ejit_movi(func, EJIT_GPR(1), 2);
char c = 0;
while ((c = *program++))
switch (c) {
case '+': ejit_addi(func, EJIT_GPR(0), EJIT_GPR(0), 1); break;
case '-': ejit_subi(func, EJIT_GPR(0), EJIT_GPR(0), 1); break;
case '*': ejit_mulr(func, EJIT_GPR(0), EJIT_GPR(0), EJIT_GPR(1)); break;
case '/': ejit_divr(func, EJIT_GPR(0), EJIT_GPR(0), EJIT_GPR(1)); break;
default: break;
}
/* return accumulator */
ejit_retr(func, EJIT_GPR(0));
/* we use GPRs 0 and 1, so 2 in total, no FPRs, and we don't use 64 bit
* values (explicitly at least) */
ejit_compile_func(func, 2, 0, false);
return func;
}
static int32_t run(struct ejit_func *func)
{
return ejit_run_func(func, 0, NULL);
}
static void destroy(struct ejit_func *func)
{
ejit_destroy_func(func);
}
int main()
{
const char *program = "+ + * - /";
struct ejit_func *func = compile(program);
if (!func) {
fprintf(stderr, "failed to compile program\n");
return -1;
}
int32_t result = run(func);
printf("%" PRIi32 "\n", result);
destroy(func);
}
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