Load and recognize a minimal set of instructions

1 files changed, 11 insertions, 4 deletions

diff --git a/src/memory.rs b/src/memory.rs
index 854b0ea..3409ed4 100644
--- a/src/memory.rs
+++ b/src/memory.rs
@@ -1,21 +1,28 @@
 use isa::{Instruction};
+use binary::{Binary};
 
 pub struct Memory {
     memory: Vec<u32>,
 }
 
 impl Memory {
-    pub fn new(size: usize) -> Memory {
+    pub fn new(size: usize, binary: Binary) -> Memory {
+        let mut memory = binary.words.clone();
+        if size > memory.len() {
+            let remainder = size - memory.len();
+            memory.reserve(remainder);
+        }
         Memory {
-            memory: Vec::with_capacity(size),
+            memory: memory,
         }
     }
 
     pub fn read_word(&self, address: usize) -> Option<u32> {
-        self.memory.get(address).map(Clone::clone)
+        // memory is word-addressed but addresses are byte-addressed
+        self.memory.get(address / 4).map(Clone::clone)
     }
 
     pub fn read_instruction(&self, pc: usize) -> Option<Instruction> {
-        self.memory.get(pc).map(Clone::clone).map(Instruction::new)
+        self.memory.get(pc / 4).map(Clone::clone).map(Instruction::new)
     }
 }