stack pointer and memsize

src/main.c

@@ -51,7 +51,7 @@ int main(int argc, char** argv){
 	}
 
 	trv_cpu cpu;
-	cpu.mem = malloc(mem_size);
+	cpu.mem = malloc(cpu.mem_size = mem_size);
 
 	//file handling
 	FILE* file = fopen(file_path, "rb");

src/tinyriscv.h

@@ -12,7 +12,7 @@ typedef int16_t i16;
 typedef int32_t i32;
 
 typedef struct{
-	u32 regs[32], pc;
+	u32 regs[32], pc, mem_size;
 	u8* mem;
 }trv_cpu;
 
@@ -174,6 +174,7 @@ void trv_step(trv_cpu* cpu){
 }
 
 void trv_init(trv_cpu* cpu){
+	cpu->regs[2] = trv_MEM_OFFSET + cpu->mem_size;
 	cpu->pc = trv_MEM_OFFSET;
 }