Add emission for functions

Able to execute "hello, world" program.

Some segmentation faults in specific test steps.

Executables not exiting on their own.

5 files changed, 96 insertions, 65 deletions

diff --git a/src/cljcc/compiler.clj b/src/cljcc/compiler.clj
index b0e5770..c1af6de 100644
--- a/src/cljcc/compiler.clj
+++ b/src/cljcc/compiler.clj
@@ -394,7 +394,7 @@
          flatten
          (remove nil?))))
 
-(defn- tacky-function->assembly-function [{:keys [type identifier parameters instructions] :as function-definition}]
+(defn- tacky-function->assembly-function [{:keys [type identifier parameters instructions]}]
   (let [parameter-instructions (parameters->assembly-instructions parameters)
         body-instructions (->> instructions
                                (keep tacky-inst->assembly-inst)
diff --git a/src/cljcc/driver.clj b/src/cljcc/driver.clj
index 8485574..14b9e18 100644
--- a/src/cljcc/driver.clj
+++ b/src/cljcc/driver.clj
@@ -9,7 +9,8 @@
    [clojure.pprint :as pp]
    [cljcc.log :as log]
    [cljcc.util :refer [get-os handle-sh mac-aarch64? make-file-name]]
-   [cljcc.parser :as p]))
+   [cljcc.parser :as p]
+   [clojure.string :as str]))
 
 (defn- validate-os []
   (let [os (get-os)]
@@ -44,7 +45,9 @@
         assembly-out-file-path (make-file-name directory (remove-extension filename) "s")
         _ (println assembly-output)
         _ (spit assembly-out-file-path assembly-output)
-        output-file (str directory "/" file-without-ext)
+        output-file (if (:generate-object-file options)
+                      (str directory "/" (str file-without-ext ".o"))
+                      (str directory "/" file-without-ext))
         output (if (:generate-object-file options)
                  (handle-sh "gcc" "-c" assembly-file "-o" output-file)
                  (handle-sh "gcc" assembly-file "-o" output-file))]
diff --git a/src/cljcc/emit.clj b/src/cljcc/emit.clj
index 8a12d76..1d8c51a 100644
--- a/src/cljcc/emit.clj
+++ b/src/cljcc/emit.clj
@@ -3,7 +3,8 @@
             [cljcc.util :refer [get-os]]
             [cljcc.compiler :as c]
             [clojure.string :as str]
-            [clojure.pprint :as pp]))
+            [clojure.pprint :as pp]
+            [cljcc.symbols :as symbols]))
 
 (defn- handle-label [identifier]
   (condp = (get-os)
@@ -11,6 +12,19 @@
     :linux (str ".L" identifier)
     (throw (ex-info "Error in generating label." {}))))
 
+
+(defn- handle-function-name [name]
+  (if (= :mac (get-os))
+    (str "_" name)
+    name))
+
+(defn- handle-current-translation-unit [name]
+  (if (= :mac (get-os))
+    (handle-function-name name)
+    (if (contains? @symbols/symbols name)
+      name
+      (str name "@PLT"))))
+
 ;;;; Operand Emit
 
 (defn- imm-opernad-emit [operand _opts]
@@ -19,24 +33,48 @@
 (defn- stack-operand-emit [operand _opts]
   (format "%d(%%rbp)" (:value operand)))
 
-(defn- register-operand [operand opts]
-  (if (contains? opts :byte-1)
-    (condp = (:register operand)
-      :ax "%al"
-      :dx "%dl"
-      :r10 "%r10b"
-      :r11 "%r11b"
-      :cx "%cl"
-      :cl "%cl"
-      (throw (AssertionError. (str "Invalid register operand: " operand))))
-    (condp = (:register operand)
-      :ax "%eax"
-      :dx "%edx"
-      :r10 "%r10d"
-      :r11 "%r11d"
-      :cx "%ecx"
-      :cl "%cl"
-      (throw (AssertionError. (str "Invalid register operand: " operand))))))
+(defn- register-operand [{:keys [register] :as operand} {register-width :register-width :or {register-width :4-byte}}]
+  (let [register->width->output {:ax {:8-byte "%rax"
+                                      :4-byte "%eax"
+                                      :1-byte "%al"}
+
+                                 :dx {:8-byte "%rdx"
+                                      :4-byte "%edx"
+                                      :1-byte "%dl"}
+
+                                 :cx {:8-byte "%rcx"
+                                      :4-byte "%ecx"
+                                      :1-byte "%cl"}
+
+                                 :di {:8-byte "%rdi"
+                                      :4-byte "%edi"
+                                      :1-byte "%dil"}
+
+                                 :si {:8-byte "%rsi"
+                                      :4-byte "%esi"
+                                      :1-byte "%sil"}
+
+                                 :r8 {:8-byte "%r8"
+                                      :4-byte "%r8d"
+                                      :1-byte "%r8b"}
+
+                                 :r9 {:8-byte "%r9"
+                                      :4-byte "%r9d"
+                                      :1-byte "%r9b"}
+
+                                 :r10 {:8-byte "%r10"
+                                       :4-byte "%r10d"
+                                       :1-byte "%r10b"}
+
+                                 :r11 {:8-byte "%r11"
+                                       :4-byte "%r11d"
+                                       :1-byte "%r11b"}
+
+                                 :cl {:4-byte "%cl"
+                                      :1-byte "%cl"}}]
+    (if-let [out (get-in register->width->output [register register-width])]
+      out
+      (throw (AssertionError. (str "Invalid register operand register width " operand " " register-width))))))
 
 (def operand-emitters
   "Map of assembly operands to operand emitters."
@@ -74,7 +112,7 @@
 
 (defn- setcc-instruction-emit [instruction]
   (let [cc (name (:cond-code instruction))
-        operand (operand-emit (:operand instruction) {:byte-1 true})]
+        operand (operand-emit (:operand instruction) {:register-width :1-byte})]
     [(format "    set%s        %s" cc operand)]))
 
 (defn- label-instruction-emit [instruction]
@@ -118,6 +156,15 @@
 (defn- allocate-stack-instruction-emit [instruction]
   [(format "    subq        $%d, %%rsp" (:value instruction))])
 
+(defn- deallocate-stack-instruction-emit [instruction]
+  [(format "    addq        $%d, %%rsp" (:value instruction))])
+
+(defn- push-instruction-emit [instruction]
+  [(format "    pushq       %s" (operand-emit (:operand instruction) {:register-width :8-byte}))])
+
+(defn- call-instruction-emit [instruction]
+  [(format "    call        %s" (handle-current-translation-unit (:identifier instruction)))])
+
 (def instruction-emitters
   "Map of assembly instructions to function emitters."
   {:mov #'mov-instruction-emit
@@ -131,19 +178,17 @@
    :jmpcc #'jmpcc-instruction-emit
    :label #'label-instruction-emit
    :cmp #'cmp-instruction-emit
-   :allocate-stack #'allocate-stack-instruction-emit})
+   :allocate-stack #'allocate-stack-instruction-emit
+   :deallocate-stack #'deallocate-stack-instruction-emit
+   :push #'push-instruction-emit
+   :call #'call-instruction-emit})
 
 (defn instruction-emit [instruction]
   (if-let [[_ instruction-emit-fn] (find instruction-emitters (:op instruction))]
     (instruction-emit-fn instruction)
     (throw (AssertionError. (str "Invalid instruction: " instruction)))))
 
-(defn- handle-function-name [name]
-  (if (= :mac (get-os))
-    (str "_" name)
-    name))
-
-(defn function-emit [f]
+(defn function-definition-emit [f]
   (let [name (handle-function-name (:identifier f))
         globl (format "    .globl %s", name)
         name-line (format "%s:" name)
@@ -156,7 +201,7 @@
 
 (def emitters-top-level
   "Map of assembly top level constructs to their emitters."
-  {:function #'function-emit})
+  {:declaration #'function-definition-emit})
 
 (defn emit-top-level [assembly-ast]
   (if-let [[_ emit-fn] (find emitters-top-level (:op assembly-ast))]
@@ -179,39 +224,10 @@
 
 (comment
 
-  (def ex "int main(void) {return 2;}")
-
-  (mov-instruction-emit
-   {:op :mov
-    :src {:operand :imm :value 1}
-    :dst {:operand :stack :value -4}})
-
-  (c/generate-assembly
-   "int main(void) {
-     return ~(-(~(-1)));
-    }")
-
-  (pp/pprint
-   (c/generate-assembly
-    "int main(void) {
-     return ~(-(~(-1)));
-    }"))
-
-  (println
    (emit
     (c/generate-assembly
      "int main(void) {
-       return 1 + 2 == 4 + 5;
-    }")))
-
-  (println
-   (emit
-    (c/generate-assembly
-     "int main(void) {
-       return 6;
-    }")))
-
-  (-> ex
-      p/parse)
+     return ~(-(~(-1)));
+    }"))
 
   ())
diff --git a/src/cljcc/symbols.clj b/src/cljcc/symbols.clj
new file mode 100644
index 0000000..1afbe47
--- /dev/null
+++ b/src/cljcc/symbols.clj
@@ -0,0 +1,10 @@
+(ns cljcc.symbols)
+
+(def symbols
+  "Holds global symbol table.
+
+  Maps identifiers to their types."
+  (atom {}))
+
+(defn reset-symbols [new-symbols]
+  (reset! symbols new-symbols))
diff --git a/src/cljcc/tacky.clj b/src/cljcc/tacky.clj
index 5451f78..1b339d9 100644
--- a/src/cljcc/tacky.clj
+++ b/src/cljcc/tacky.clj
@@ -4,7 +4,8 @@
    [cljcc.lexer :as l]
    [cljcc.util :as u]
    [cljcc.parser :as p]
-   [cljcc.analyzer :as a]))
+   [cljcc.analyzer :as a]
+   [cljcc.symbols :as symbols]))
 
 (defn- variable
   ([]
@@ -379,8 +380,9 @@
         (dissoc :body)
         (assoc :instructions instructions))))
 
-(defn tacky-generate [{ast :block}]
-  (let [defined? (fn [x] (seq (:body x)))]
+(defn tacky-generate [{ast :block symbols :decl-name->symbol}]
+  (let [_ (symbols/reset-symbols symbols)
+        defined? (fn [x] (or (= (:identifier x) "main") (seq (:body x))))]
    (->> ast
        (filter defined?)
        (map function-definition->tacky-function))))