task: using a runbook

tutorial/index.md

@@ -264,3 +264,19 @@ trying out the next one.)
 Runbooks are a handy tool for working with computers. In a runbook you write
 instructions to your future self or for others you're working with. They're
 instructions for programming people, not computers.
+
+## Task 7: variables in registers, variables in memory (again)
+
+Go back to your program in Task 5. Replace the first statement declaring
+variable `x`:
+```
+var x: int
+```
+
+so it looks like this:
+```
+var x/edx: int <- copy 0
+```
+
+Run `translate` (or `translate_emulated`) as usual. Use your runbook from Task
+6 to address the errors that arise.

tutorial/task7-solution.mu

@@ -0,0 +1,18 @@
+fn foo -> _/eax: int {
+  var x/edx: int <- copy 0
+  # statement 1: store 3 in x
+  x <- copy 3
+  # statement 2: define a new variable 'y' in register eax and store 4 in it
+  var y/eax: int <- copy 4
+  # statement 3: add y to x, storing the result in x
+  x <- add y
+  return x
+}
+
+fn test-foo {
+  var result/eax: int <- foo
+  check-ints-equal result, 7, "F - foo should return 7, but didn't"
+}
+
+fn main {
+}

tutorial/task7.mu

@@ -0,0 +1,18 @@
+fn foo -> _/eax: int {
+  var x/edx: int <- copy 0
+  # statement 1: store 3 in x
+  copy-to x, 3
+  # statement 2: define a new variable 'y' in register eax and store 4 in it
+  var y/eax: int <- copy 4
+  # statement 3: add y to x, storing the result in x
+  add-to x, y
+  return x
+}
+
+fn test-foo {
+  var result/eax: int <- foo
+  check-ints-equal result, 7, "F - foo should return 7, but didn't"
+}
+
+fn main {
+}