Add assembly generation for unary operators

Adding assembly generation

New opcodes, operands

1 files changed, 47 insertions, 0 deletions

diff --git a/src/cljcc/emit.clj b/src/cljcc/emit.clj
new file mode 100644
index 0000000..3cd4f00
--- /dev/null
+++ b/src/cljcc/emit.clj
@@ -0,0 +1,47 @@
+(ns cljcc.emit
+  (:require [cljcc.parser :as p]
+            [cljcc.util :refer [get-os]]
+            [clojure.string :as str]))
+
+(defn handle-function-name [name]
+  (if (= :mac (get-os))
+    (str "_" name)
+    name))
+
+(defn emit-instruction
+  ([inst]
+   (str "    " (symbol inst)))
+  ([inst src dst]
+   (str "    " (symbol inst) "    " "$" src ", %" (symbol dst))))
+
+(defn statement-fn [stmt]
+  (condp = (:op stmt)
+    :ret (emit-instruction :ret)
+    :movl (emit-instruction (:op stmt) (:src stmt) (:dst stmt))))
+
+(defn emit-function-assembly [fn-ast]
+  (let [name (handle-function-name (:identifier fn-ast))
+        globl-line (str "    .globl " name)
+        fn-start-line (str name ":")
+        body-statements (map statement-fn (:body fn-ast))]
+    (flatten [globl-line fn-start-line body-statements])))
+
+(def linux-assembly-end ".section .note.GNU-stack,\"\",@progbits")
+
+(defn emit-assembly [ast]
+  (let [fn-assembly (emit-function-assembly (first ast))]
+    (if (= :linux (get-os))
+      (concat fn-assembly [linux-assembly-end])
+      fn-assembly)))
+
+(defn join-assembly [assembly-lines]
+  (str/join "\n" assembly-lines))
+
+(comment
+
+  (def ex "int main(void) {return 2;}")
+
+  (-> ex
+      p/parse)
+
+  ())