Merge pull request 'Новая инструкция: rjmp' (#1) from rjmp into master

Reviewed-on: #1

src/execute.rs

@@ -89,6 +89,7 @@ pub fn execute(stack: &mut Stack, mut origin_stack: Option<&mut Stack>, mod_name
 
             // Labels
             "jmp"  => instructions::jmp::jmp(&mut stack.labels, &mut stack.program_counter, instruction.data),
+            "rjmp" => instructions::rjmp::rjmp(&mut stack.memory, &mut stack.labels, &mut stack.program_counter),
             "jnz"  => instructions::jnz::jnz(&mut stack.memory, &mut stack.labels, &mut stack.program_counter, instruction.data),
             "jz"   => instructions::jz::jz(&mut stack.memory, &mut stack.labels, &mut stack.program_counter, instruction.data),
             "kjnz" => instructions::kjnz::kjnz(&mut stack.memory, &mut stack.labels, &mut stack.program_counter, instruction.data),

src/instructions/mod.rs

@@ -39,3 +39,4 @@ pub mod print;
 pub mod println;
 pub mod insert;
 pub mod random;
+pub mod rjmp;

src/instructions/rjmp.rs

@@ -0,0 +1,9 @@
+use crate::{errors::RunError, stack::StackVec};
+
+pub fn rjmp(memory: &mut StackVec, labels: &mut [Option<i16>; 256], program_counter: &mut u16) {
+    let start = memory.pop() as usize;
+    let end   = memory.pop() as usize;
+    let rand  = fastrand::usize(start..end + 1);
+
+    *program_counter = (labels[rand].expect(&format!("{}", RunError::UnknownLabel(rand as u16))) - 1) as u16;
+}