X-Git-Url: http://git.joshuawise.com/snipe.git/blobdiff_plain/0a24e44d4e9f82f8d3d83de8e58c83c8cf2868b6..HEAD:/codegen/codegen.sml?ds=sidebyside

diff --git a/codegen/codegen.sml b/codegen/codegen.sml
index 9b99ef7..18ac4af 100644
--- a/codegen/codegen.sml
+++ b/codegen/codegen.sml
@@ -1,4 +1,4 @@
-(* L2 Compiler
+(* L3 Compiler
  * Assembly code generator for fake x86 assembly
  * Author: Joshua Wise <jwise@andrew.cmu.edu>
  * Author: Chris Lu <czl@andrew.cmu.edu>
@@ -12,175 +12,455 @@ end
 structure Codegen :> CODEGEN = 
 struct
   structure T = Tree
+  structure TU = TreeUtils
   structure X = x86
+  structure Tm = Temp
+
+  (* hasfixed : T.exp -> bool
+   * true iff the given expression has an hasfixed.
+   *)
+  fun hasfixed (T.BINOP(T.DIV, _, _)) = true
+    | hasfixed (T.BINOP(T.MOD, _, _)) = true
+    | hasfixed (T.BINOP(T.LSH, _, _)) = true
+    | hasfixed (T.BINOP(T.RSH, _, _)) = true
+    | hasfixed (T.CALL _) = true
+    | hasfixed (T.BINOP(_, a, b)) = (hasfixed a) orelse (hasfixed b)
+    | hasfixed (T.UNOP (_, a)) = hasfixed a
+    | hasfixed (T.ALLOC(_)) = true
+    | hasfixed (T.MEMORY (m,s)) = hasfixed m
+    | hasfixed (T.STMVAR _) = true
+    | hasfixed _ = false
+
+  fun offshit a b 0w4 d = [X.LEA(d, (X.REL((a, Tm.Quad), (b, Tm.Quad), 0w4), Tm.Quad))]
+    | offshit a b 0w8 d = [X.LEA(d, (X.REL((a, Tm.Quad), (b, Tm.Quad), 0w8), Tm.Quad))]
+    | offshit a b n d   = [X.IMUL((b, Tm.Long), (X.CONST n, Tm.Long)), X.MOV(d, (a, Tm.Quad)), X.ADD(d, (b, Tm.Quad))]
+
+  fun binophit_c d oper e c = let val (i, s) = munch_exp d e in (i @ [oper ((d,s), (X.CONST c, s))], s) end
+  and binophit_t d oper e t =
+    let
+      val (i, s) = munch_exp d e
+      val ts = Tm.size t
+      val rs = if Tm.cmpsize (s, ts) = GREATER then s else ts
+    in
+      (i @ [oper ((d, rs), (X.TEMP t, rs))], rs)
+    end
+  and binophit d oper e1 e2 =
+    let
+      val t = X.TEMP (Tm.new "add" Tm.Long)
+      val (i1, s1) = munch_exp d e1
+      val (i2, s2) = munch_exp t e2
+(*      val _ = print ("s1 = " ^ Tm.sfx s1 ^ ", s2 = " ^ Tm.sfx s2 ^ ", ") *)
+      val rs = if Tm.cmpsize (s1, s2) = GREATER then s1 else s2
+(*      val _ = print ("rs = " ^ Tm.sfx rs ^ " from " ^ TU.Print.pp_exp e1 ^ " and " ^ TU.Print.pp_exp e2 ^ "\n") *)
+    in
+      (i1 @ i2 @ [oper ((d,rs), (t,rs))], rs)
+    end
+  and cmphit d a = let val (insns, pos, neg) = munch_cond a in (insns @ [X.SETcc (pos, (d, Tm.Byte)), X.MOVZB((d, Tm.Long), (d, Tm.Byte))], Tm.Long) end
 
   (* munch_exp : prex86oper -> T.exp -> prex86insn list *)
   (* munch_exp d e
    * generates instructions to achieve d <- e
    * d must be TEMP(t) or REG(r)
    *)
-  fun munch_exp d (T.CONST(n)) = [X.MOVL(d, X.CONST n)]
-    | munch_exp d (T.TEMP(t)) = [X.MOVL(d, X.TEMP t)]
-    | munch_exp d (T.BINOP(T.ADD, e1, T.CONST n)) = (munch_exp d e1) @ [X.ADDL(d, X.CONST n)]
-    | munch_exp d (T.BINOP(T.ADD, T.CONST n, e1)) = (munch_exp d e1) @ [X.ADDL(d, X.CONST n)]
-    | munch_exp d (T.BINOP(T.ADD, e1, e2)) =
-        let
-          val t1 = Temp.new ()
-        in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @ [X.ADDL(d, X.TEMP t1)]
-        end
-    | munch_exp d (T.BINOP(T.SUB, T.CONST 0w0, e1)) = (munch_exp d e1) @ [X.NEG d]
-    | munch_exp d (T.BINOP(T.SUB, e1, T.CONST(n))) = (munch_exp d e1) @ [X.SUBL(d, X.CONST n)]
-    | munch_exp d (T.BINOP(T.SUB, e1, e2)) =
-        let val
-          t1 = Temp.new ()
-        in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @ [X.SUBL(d, X.TEMP t1)]
-        end
-    | munch_exp d (T.BINOP(T.MUL, T.TEMP t, T.CONST n)) = [X.IMUL3(d, X.TEMP t, n)]
-    | munch_exp d (T.BINOP(T.MUL, T.CONST n, T.TEMP t)) = [X.IMUL3(d, X.TEMP t, n)]
-    | munch_exp d (T.BINOP(T.MUL, e1, T.CONST n)) = (munch_exp d e1) @ [X.IMUL(d, X.CONST n)]
-    | munch_exp d (T.BINOP(T.MUL, T.CONST n, e1)) = (munch_exp d e1) @ [X.IMUL(d, X.CONST n)]
-    | munch_exp d (T.BINOP(T.MUL, e1, e2)) =
+  and munch_exp d (T.CONST n) = ([X.MOV((d, Tm.Long), (X.CONST n, Tm.Long))], Tm.Long)
+    | munch_exp d (T.NULLPTR) = ([X.MOV((d, Tm.Quad), (X.CONST 0w0, Tm.Quad))], Tm.Quad)
+    | munch_exp d (T.TEMP(t)) = ([X.MOV((d, Tm.size t), (X.TEMP t, Tm.size t))], Tm.size t)
+    | munch_exp d (T.ARG(0, sz)) = ([X.MOV((d, sz), (X.REG X.EDI, sz))], sz)
+    | munch_exp d (T.ARG(1, sz)) = ([X.MOV((d, sz), (X.REG X.ESI, sz))], sz)
+    | munch_exp d (T.ARG(2, sz)) = ([X.MOV((d, sz), (X.REG X.EDX, sz))], sz)
+    | munch_exp d (T.ARG(3, sz)) = ([X.MOV((d, sz), (X.REG X.ECX, sz))], sz)
+    | munch_exp d (T.ARG(4, sz)) = ([X.MOV((d, sz), (X.REG X.R8D, sz))], sz)
+    | munch_exp d (T.ARG(5, sz)) = ([X.MOV((d, sz), (X.REG X.R9D, sz))], sz)
+    | munch_exp d (T.ARG(t, sz)) = ([X.MOV((d, sz), (X.STACKARG (t - 6), sz))], sz)
+    | munch_exp d (T.CALL(name, l, rsz)) = (* Scary demons live here. *)
         let
-          val t1 = Temp.new ()
+          val nargs = length l
+          val nstack = if (nargs <= 6)
+                       then 0
+                       else nargs - 6
+          val stackb = nstack * 8
+          fun argdest 1 = X.REG X.EDI
+            | argdest 2 = X.REG X.ESI
+            | argdest 3 = X.REG X.EDX
+            | argdest 4 = X.REG X.ECX
+            | argdest 5 = X.REG X.R8D
+            | argdest 6 = X.REG X.R9D
+            | argdest n = X.REL ((X.REG X.RSP, Tm.Quad), (X.CONST (Word32.fromInt (~(stackb - 8 * (n - 7)))), Tm.Quad), 0w1)
+
+          val dests = List.tabulate (nargs, fn x => argdest (x+1))
+          val (exps,_) = ListPair.unzip l
+          val hf = List.map hasfixed exps
+          val (d_hf, l_hf) = ListPair.unzip (ListPair.foldr
+            (fn (a,b,c) => if b then a::c else c)
+            nil
+            (ListPair.zip (dests,l), hf)
+          )
+          val (d_nohf, l_nohf) = ListPair.unzip (ListPair.foldr
+            (fn (a,b,c) => if b then c else a::c)
+            nil
+            (ListPair.zip (dests,l), hf)
+          )
+          val temps = List.map (fn (_, sz) => Temp.new ("arg") sz (* xxx? *)) l_hf
+          val (argevals_hf,_) = ListPair.unzip (List.map
+            (fn (t,(exp,_)) => munch_exp (X.TEMP t) exp)
+            (ListPair.zip (temps, l_hf)))
+          val argpushes = List.map
+            (fn (dest, t) => [X.MOV ((dest, Tm.size t), (X.TEMP t, Tm.size t))])
+            (ListPair.zip (d_hf, temps))
+          val (argevals_nohf,_) = ListPair.unzip (List.map
+            (fn (d,(exp,sz)) => munch_exp d exp)
+            (ListPair.zip (d_nohf, l_nohf)))
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @ [X.IMUL(d, X.TEMP t1)]
+          (List.concat argevals_hf @ 
+           List.concat argpushes @
+           List.concat argevals_nohf @
+           [ X.SUB ((X.REG X.RSP, Tm.Quad), (X.CONST (Word32.fromInt stackb), Tm.Quad)),
+             X.CALL (name, nargs),
+             X.ADD ((X.REG X.RSP, Tm.Quad), (X.CONST (Word32.fromInt stackb), Tm.Quad)),
+             X.MOV ((d, rsz), (X.REG X.EAX, rsz))], rsz)      (* Finally! *)
         end
+    | munch_exp d (T.BINOP(T.ADD, e1, T.CONST n)) = binophit_c d X.ADD e1 n
+    | munch_exp d (T.BINOP(T.ADD, T.CONST n, e1)) = binophit_c d X.ADD e1 n
+    | munch_exp d (T.BINOP(T.ADD, e1, T.TEMP t)) = binophit_t d X.ADD e1 t
+    | munch_exp d (T.BINOP(T.ADD, T.TEMP t, e1)) = binophit_t d X.ADD e1 t
+    | munch_exp d (T.BINOP(T.ADD, e1, e2)) = binophit d X.ADD e1 e2
+
+    | munch_exp d (T.BINOP(T.SUB, e1, T.CONST n)) = binophit_c d X.SUB e1 n
+    | munch_exp d (T.BINOP(T.SUB, e1, T.TEMP t)) = binophit_t d X.SUB e1 t
+    | munch_exp d (T.BINOP(T.SUB, e1, e2)) = binophit d X.SUB e1 e2
+    | munch_exp d (T.BINOP(T.MUL, T.TEMP t, T.CONST n)) = let val s = Tm.size t in ([X.IMUL3((d,s), (X.TEMP t,s), n)], Tm.size t) end
+    | munch_exp d (T.BINOP(T.MUL, T.CONST n, T.TEMP t)) = let val s = Tm.size t in ([X.IMUL3((d,s), (X.TEMP t,s), n)], Tm.size t) end
+    | munch_exp d (T.BINOP(T.MUL, e1, T.CONST n)) = binophit_c d X.IMUL e1 n
+    | munch_exp d (T.BINOP(T.MUL, T.CONST n, e1)) = binophit_c d X.IMUL e1 n
+    | munch_exp d (T.BINOP(T.MUL, e1, e2)) = binophit d X.IMUL e1 e2
     | munch_exp d (T.BINOP(T.DIV, e1, e2)) =
         let
-          val t1 = Temp.new ()
+          val t1 = X.TEMP (Temp.new ("div") Tm.Long)
+          val (i1, s1) = munch_exp t1 e1
+          val (i2, s2) = munch_exp d e2
         in
-          (munch_exp (X.TEMP t1) e1) @ (munch_exp d e2) @
-          [X.MOVL (X.REG X.EAX, X.TEMP t1), X.CLTD, X.IDIVL d, X.MOVL (d, X.REG X.EAX)]
+          (i1 @ i2 @ [X.MOV ((X.REG X.EAX, s1), (t1, s1)), X.CLTD, X.IDIV (d, s2), X.MOV ((d, s2), (X.REG X.EAX, s2))], Tm.Long)
         end
     | munch_exp d (T.BINOP(T.MOD, e1, e2)) =
         let
-          val t1 = Temp.new ()
+          val t1 = X.TEMP (Temp.new ("div") Tm.Long)
+          val (i1, s1) = munch_exp t1 e1
+          val (i2, s2) = munch_exp d e2
         in
-          (munch_exp (X.TEMP t1) e1) @ (munch_exp d e2) @
-          [X.MOVL (X.REG X.EAX, X.TEMP t1), X.CLTD, X.IDIVL d, X.MOVL (d, X.REG X.EDX)]
+          (i1 @ i2 @ [X.MOV ((X.REG X.EAX, s1), (t1, s1)), X.CLTD, X.IDIV (d, s2), X.MOV ((d, s2), (X.REG X.EDX, s2))], Tm.Long)
         end
-    | munch_exp d (T.BINOP(T.LSH, e1, T.CONST n)) = (munch_exp d e1) @ [X.SALL (d, X.CONST n)]
-    | munch_exp d (T.BINOP(T.LSH, e1, e2)) =
+    | munch_exp d (T.BINOP(T.LSH, e1, T.CONST n)) = let val (i,s) = munch_exp d e1 in (i @ [X.SAL ((d,s), (X.CONST (n mod 0w32),s))],s) end
+    | munch_exp d (T.BINOP(T.LSH, e1, T.TEMP t)) =
         let
-          val t1 = Temp.new()
-        in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @
-          [X.MOVL (X.REG X.ECX, X.TEMP t1), X.SALL (d, X.REG X.ECX)]
+          val (i,s) = munch_exp d e1
+        in 
+          (i @ [X.MOV ((X.REG X.ECX, s), (X.TEMP t, s)), X.SAL ((d,s), (X.REG X.ECX, Tm.Byte))], s)
         end
-    | munch_exp d (T.BINOP(T.RSH, e1, T.CONST n)) = (munch_exp d e1) @ [X.SARL (d, X.CONST n)]
-    | munch_exp d (T.BINOP(T.RSH, e1, e2)) =
+    | munch_exp d (T.BINOP(T.LSH, e1, e2)) =
         let
-          val t1 = Temp.new()
+          val t = X.TEMP (Temp.new ("lsh") Tm.Long)
+          val (i1, s1) = munch_exp d e1
+          val (i2, s2) = munch_exp t e2
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @
-          [X.MOVL (X.REG X.ECX, X.TEMP t1), X.SARL (d, X.REG X.ECX)]
+          (i1 @ i2 @ [X.MOV ((X.REG X.ECX, s1), (t, s1)), X.SAL ((d, s2), (X.REG X.ECX, Tm.Byte))], s2)
         end
-    | munch_exp d (T.BINOP(T.LOGOR, e1, e2)) =
+    | munch_exp d (T.BINOP(T.RSH, e1, T.CONST n)) = let val (i,s) = munch_exp d e1 in (i @ [X.SAR ((d,s), (X.CONST (n mod 0w32),s))],s) end
+    | munch_exp d (T.BINOP(T.RSH, e1, T.TEMP t)) =
         let
-          val l1 = Label.new()
-        in
-          (munch_exp d e1) @ [X.CMPL (d, X.CONST(0w0)), X.JNE l1] @ (munch_exp d e2) @ [X.CMPL (d, X.CONST(0w0)), X.LABEL l1, X.SETNE d, X.MOVZBL(d,d)]
+          val (i,s) = munch_exp d e1
+        in 
+          (i @ [X.MOV ((X.REG X.ECX, s), (X.TEMP t, s)), X.SAR ((d,s), (X.REG X.ECX, Tm.Byte))], s)
         end
-    | munch_exp d (T.BINOP(T.LOGAND, e1, e2)) =
+    | munch_exp d (T.BINOP(T.RSH, e1, e2)) =
         let
-          val l1 = Label.new()
+          val t = X.TEMP (Temp.new ("lsh") Tm.Long)
+          val (i1, s1) = munch_exp d e1
+          val (i2, s2) = munch_exp t e2
         in
-          (munch_exp d e1) @ [X.CMPL (d, X.CONST(0w0)), X.JE l1] @ (munch_exp d e2) @ [X.CMPL (d, X.CONST(0w0)), X.LABEL l1, X.SETNE d, X.MOVZBL(d,d)]
+          (i1 @ i2 @ [X.MOV ((X.REG X.ECX, s1), (t, s1)), X.SAR ((d, s2), (X.REG X.ECX, Tm.Byte))], s2)
         end
-    | munch_exp d (T.BINOP(T.BITAND, e1, e2)) =
+    | munch_exp d (T.BINOP(T.BITAND, T.CONST n, e1)) = binophit_c d X.AND e1 n
+    | munch_exp d (T.BINOP(T.BITAND, e1, T.CONST n)) = binophit_c d X.AND e1 n
+    | munch_exp d (T.BINOP(T.BITAND, T.TEMP t, e1)) = binophit_t d X.AND e1 t
+    | munch_exp d (T.BINOP(T.BITAND, e1, T.TEMP t)) = binophit_t d X.AND e1 t
+    | munch_exp d (T.BINOP(T.BITAND, e1, e2)) = binophit d X.AND e1 e2
+
+    | munch_exp d (T.BINOP(T.BITOR, T.CONST n, e1)) = binophit_c d X.OR e1 n
+    | munch_exp d (T.BINOP(T.BITOR, e1, T.CONST n)) = binophit_c d X.OR e1 n
+    | munch_exp d (T.BINOP(T.BITOR, T.TEMP t, e1)) = binophit_t d X.OR e1 t
+    | munch_exp d (T.BINOP(T.BITOR, e1, T.TEMP t)) = binophit_t d X.OR e1 t
+    | munch_exp d (T.BINOP(T.BITOR, e1, e2)) = binophit d X.OR e1 e2
+
+    | munch_exp d (T.BINOP(T.BITXOR, T.CONST n, e1)) = binophit_c d X.XOR e1 n
+    | munch_exp d (T.BINOP(T.BITXOR, e1, T.CONST n)) = binophit_c d X.XOR e1 n
+    | munch_exp d (T.BINOP(T.BITXOR, T.TEMP t, e1)) = binophit_t d X.XOR e1 t
+    | munch_exp d (T.BINOP(T.BITXOR, e1, T.TEMP t)) = binophit_t d X.XOR e1 t
+    | munch_exp d (T.BINOP(T.BITXOR, e1, e2)) = binophit d X.XOR e1 e2
+
+    | munch_exp d (a as T.BINOP(T.LOGAND, e1, e2)) =
         let
-          val t1 = Temp.new ()
+          val (insn1, pos1, neg1) = munch_cond e1
+          val (insn2, pos2, neg2) = munch_cond e2
+          val t1 = (X.TEMP (Tm.new "logand 1" Tm.Byte), Tm.Byte)
+          val t2 = (X.TEMP (Tm.new "logand 2" Tm.Byte), Tm.Byte)
+          val l = Label.new ()
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @ [X.ANDL(d, X.TEMP t1)]
+          if (TU.effect e2 orelse (length insn2 > 10))
+          then ((insn1) @
+                [X.SETcc(pos1, t1), X.Jcc (neg1, l)] @
+                (insn2) @
+                [X.SETcc(pos2, t1), X.LABEL l, X.MOVZB((d, Tm.Long), t1)], Tm.Long)
+          else (insn1 @ [X.SETcc (pos1, t1)] @ insn2 @ [X.SETcc (pos2, t2), X.AND(t1,t2), X.MOVZB((d, Tm.Long), t1)], Tm.Long)
         end
-    | munch_exp d (T.BINOP(T.BITOR, e1, e2)) =
+    | munch_exp d (a as T.BINOP(T.LOGOR, e1, e2)) =
         let
-          val t1 = Temp.new ()
+          val (insn1, pos1, neg1) = munch_cond e1
+          val (insn2, pos2, neg2) = munch_cond e2
+          val t1 = (X.TEMP (Tm.new "logand 1" Tm.Byte), Tm.Byte)
+          val t2 = (X.TEMP (Tm.new "logand 2" Tm.Byte), Tm.Byte)
+          val l = Label.new ()
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @ [X.ORL(d, X.TEMP t1)]
+          if (TU.effect e2 orelse (length insn2 > 10))
+          then ((insn1) @
+                [X.SETcc(pos1, t1), X.Jcc (pos1, l)] @
+                (insn2) @
+                [X.SETcc(pos2, t1), X.LABEL l, X.MOVZB((d, Tm.Long), t1)], Tm.Long)
+          else (insn1 @ [X.SETcc (pos1, t1)] @ insn2 @ [X.SETcc (pos2, t2), X.OR(t1,t2), X.MOVZB((d, Tm.Long), t1)], Tm.Long)
         end
-    | munch_exp d (T.BINOP(T.BITXOR, e1, e2)) =
+    | munch_exp d (a as T.BINOP(T.EQ, _, _)) = cmphit d a
+    | munch_exp d (a as T.BINOP(T.NEQ, _, _)) = cmphit d a
+    | munch_exp d (a as T.BINOP(T.LE, _, _)) = cmphit d a
+    | munch_exp d (a as T.BINOP(T.LT, _, _)) = cmphit d a
+    | munch_exp d (a as T.BINOP(T.GE, _, _)) = cmphit d a
+    | munch_exp d (a as T.BINOP(T.GT, _, _)) = cmphit d a
+    | munch_exp d (a as T.BINOP(T.BE, _, _)) = cmphit d a
+
+    | munch_exp d (T.UNOP(T.NEG, e1)) = let val (i, s) = munch_exp d e1 in (i @ [X.NEG (d, Tm.Long)], s) end
+    | munch_exp d (T.UNOP(T.BITNOT, e1)) = let val (i, s) = munch_exp d e1 in (i @ [X.NOT (d, Tm.Long)], s) end
+    | munch_exp d (T.UNOP(T.BANG, e)) = 
         let
-          val t1 = Temp.new ()
+          val (insns, pos, neg) = munch_cond e
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @ [X.XORL(d, X.TEMP t1)]
+          (insns @ [X.SETcc (neg, (d, Tm.Byte)), X.MOVZB((d, Tm.Long), (d, Tm.Byte))], Tm.Long)
         end
-    | munch_exp d (T.BINOP(T.NEQ, e1, e2)) =
+    | munch_exp d (T.MEMORY (e1,s)) =
         let
-          val t1 = Temp.new ()
+          val a = X.TEMP (Temp.new "addr" Tm.Quad)
+          val (i, s') = munch_exp a e1
+          val _ = if s' = Tm.Quad then () else raise ErrorMsg.InternalError "memory fuxed."
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @
-          [X.CMPL(d, X.TEMP t1), X.SETNE(d), X.MOVZBL(d, d)]
+          (i @ [X.MOV ((d,s), (X.REL ((a, Tm.Quad), (X.CONST 0w0, Tm.Quad), 0w1), s))], s)
         end
-    | munch_exp d (T.BINOP(T.EQ, e1, e2)) =
+    | munch_exp d (T.ALLOC(exp)) =
+        
         let
-          val t1 = Temp.new ()
+          val t1 = Temp.new "alloc" Tm.Long
+          val l1 = Label.new()
+          val (einsn, _) = munch_exp (X.TEMP t1) exp
+          val (insns, _) = munch_exp d (T.CALL (Symbol.symbol "calloc", [(T.TEMP t1, Tm.Long), (T.CONST 0w1, Tm.Long)], Tm.Quad))
+          val rd = (d, Tm.Quad)
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @
-          [X.CMPL(d, X.TEMP t1), X.SETE(d), X.MOVZBL(d, d)]
+          (einsn @ insns, Tm.Quad)
         end
-    | munch_exp d (T.BINOP(T.LE, e1, e2)) =
+(*    | munch_exp d (T.COND(c, T.CONST n1, T.CONST n2)) = let val (i,p,n) = munch_cond c in ((X.MOV (d, X.CONST n1))::i) @ [X.CMOVcc (p, d, X.CONST n2)] end *)
+    | munch_exp d (T.COND(c,e1,e2)) =
         let
-          val t1 = Temp.new ()
+          val (insns, pos, neg) = munch_cond c
+          val l1 = Label.new()
+          val l2 = Label.new()
+          val (i1, s1) = munch_exp d e1
+          val (i2, s2) = munch_exp d e2
+(*          val _ = print ("cond: size " ^ Tm.sfx s1 ^ " from " ^ TU.Print.pp_exp e1 ^ ", " ^ Tm.sfx s2 ^ " from " ^ TU.Print.pp_exp e2 ^ "\n") *)
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @
-          [X.CMPL(d, X.TEMP t1), X.SETLE(d), X.MOVZBL(d, d)]
+          (insns @ [X.Jcc(neg, l1)] @ i1 @ [X.JMP l2, X.LABEL l1] @ i2 @ [X.LABEL l2], if s1 = s2 then s1 else raise ErrorMsg.InternalError "condfuxed.")
         end
-    | munch_exp d (T.BINOP(T.LT, e1, e2)) =
+    | munch_exp d (T.STMVAR (sl, e)) = let val (i, s) = munch_exp d e in (List.concat (map munch_stm sl) @ i, s) end
+
+  and condhit_tc t c (pos, neg) = ([X.CMP((X.TEMP t, Tm.size t), (X.CONST c, Tm.size t))], pos, neg)
+  and condhit_c e c (pos, neg) =
+    let
+      val t = X.TEMP (Temp.new "consthit" Tm.Long)
+      val (i,s) = munch_exp t e
+    in
+      (i @ [X.CMP ((t,s), (X.CONST c,s))], pos, neg)
+    end
+  and condhit_t e t (pos, neg) =
+    let
+      val t' = X.TEMP (Temp.new "consthit" Tm.Long)
+      val (i,s) = munch_exp t' e
+    in
+      (i @ [X.CMP ((t',s), (X.TEMP t,s))], pos, neg)
+    end
+  and condhit e1 e2 (pos, neg) =
+    let
+      val t1 = X.TEMP (Temp.new ("var neq 1") Tm.Long)
+      val t2 = X.TEMP (Temp.new ("var neq 2") Tm.Long)
+      val (i1, s1) = munch_exp t1 e1
+      val (i2, s2) = munch_exp t2 e2
+    in
+      (i1 @ i2 @ [X.CMP((t1,s1),(t2,s2))], pos, neg)
+    end
+
+  (* munch_cond : T.exp -> X.insn list * X.cond * X.cond
+   * munch_cond stm generates code to set flags, and then returns a conditional
+   * to test if the expression was true and for if it was false.
+   *)
+  and munch_cond (T.UNOP (T.BANG, e)) =
         let
-          val t1 = Temp.new ()
+          val (insns, pos, neg) = munch_cond e
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @
-          [X.CMPL(d, X.TEMP t1), X.SETL(d), X.MOVZBL(d, d)]
+          (insns, neg, pos)
         end
-    | munch_exp d (T.BINOP(T.GE, e1, e2)) =
+    | munch_cond (T.BINOP(T.NEQ, T.TEMP t, T.CONST n)) = condhit_tc t n (X.NE, X.E)
+    | munch_cond (T.BINOP(T.NEQ, T.CONST n, T.TEMP t)) = condhit_tc t n (X.NE, X.E)
+    | munch_cond (T.BINOP(T.NEQ, T.CONST n, e1)) = condhit_c e1 n (X.NE, X.E)
+    | munch_cond (T.BINOP(T.NEQ, e1, T.CONST n)) = condhit_c e1 n (X.NE, X.E)
+    | munch_cond (T.BINOP(T.NEQ, T.TEMP t, e1)) = condhit_t e1 t (X.NE, X.E)
+    | munch_cond (T.BINOP(T.NEQ, e1, T.TEMP t)) = condhit_t e1 t (X.NE, X.E)
+    | munch_cond (T.BINOP(T.NEQ, e1, e2)) = condhit e1 e2 (X.NE, X.E)
+
+    | munch_cond (T.BINOP(T.EQ, T.TEMP t, T.CONST n)) = condhit_tc t n (X.E, X.NE)
+    | munch_cond (T.BINOP(T.EQ, T.CONST n, T.TEMP t)) = condhit_tc t n (X.E, X.NE)
+    | munch_cond (T.BINOP(T.EQ, T.CONST n, e1)) = condhit_c e1 n (X.E, X.NE)
+    | munch_cond (T.BINOP(T.EQ, e1, T.CONST n)) = condhit_c e1 n (X.E, X.NE)
+    | munch_cond (T.BINOP(T.EQ, T.TEMP t, e1)) = condhit_t e1 t (X.E, X.NE)
+    | munch_cond (T.BINOP(T.EQ, e1, T.TEMP t)) = condhit_t e1 t (X.E, X.NE)
+    | munch_cond (T.BINOP(T.EQ, e1, e2)) = condhit e1 e2 (X.E, X.NE)
+
+    | munch_cond (T.BINOP(T.LE, T.TEMP t, T.CONST n)) = condhit_tc t n (X.LE, X.G)
+    | munch_cond (T.BINOP(T.LE, T.CONST n, T.TEMP t)) = condhit_tc t n (X.GE, X.L)
+    | munch_cond (T.BINOP(T.LE, T.CONST n, e1)) = condhit_c e1 n (X.GE, X.L)
+    | munch_cond (T.BINOP(T.LE, e1, T.CONST n)) = condhit_c e1 n (X.LE, X.G)
+    | munch_cond (T.BINOP(T.LE, T.TEMP t, e1)) = condhit_t e1 t (X.GE, X.L)
+    | munch_cond (T.BINOP(T.LE, e1, T.TEMP t)) = condhit_t e1 t (X.LE, X.G)
+    | munch_cond (T.BINOP(T.LE, e1, e2)) = condhit e1 e2 (X.LE, X.G)
+
+    | munch_cond (T.BINOP(T.LT, T.TEMP t, T.CONST n)) = condhit_tc t n (X.L, X.GE)
+    | munch_cond (T.BINOP(T.LT, T.CONST n, T.TEMP t)) = condhit_tc t n (X.G, X.LE)
+    | munch_cond (T.BINOP(T.LT, T.CONST n, e1)) = condhit_c e1 n (X.G, X.LE)
+    | munch_cond (T.BINOP(T.LT, e1, T.CONST n)) = condhit_c e1 n (X.L, X.GE)
+    | munch_cond (T.BINOP(T.LT, T.TEMP t, e1)) = condhit_t e1 t (X.G, X.LE)
+    | munch_cond (T.BINOP(T.LT, e1, T.TEMP t)) = condhit_t e1 t (X.L, X.GE)
+    | munch_cond (T.BINOP(T.LT, e1, e2)) = condhit e1 e2 (X.L, X.GE)
+
+    | munch_cond (T.BINOP(T.GT, T.TEMP t, T.CONST n)) = condhit_tc t n (X.G, X.LE)
+    | munch_cond (T.BINOP(T.GT, T.CONST n, T.TEMP t)) = condhit_tc t n (X.L, X.GE)
+    | munch_cond (T.BINOP(T.GT, T.CONST n, e1)) = condhit_c e1 n (X.L, X.GE)
+    | munch_cond (T.BINOP(T.GT, e1, T.CONST n)) = condhit_c e1 n (X.G, X.LE)
+    | munch_cond (T.BINOP(T.GT, T.TEMP t, e1)) = condhit_t e1 t (X.L, X.GE)
+    | munch_cond (T.BINOP(T.GT, e1, T.TEMP t)) = condhit_t e1 t (X.G, X.LE)
+    | munch_cond (T.BINOP(T.GT, e1, e2)) = condhit e1 e2 (X.G, X.LE)
+
+    | munch_cond (T.BINOP(T.GE, T.TEMP t, T.CONST n)) = condhit_tc t n (X.GE, X.L)
+    | munch_cond (T.BINOP(T.GE, T.CONST n, T.TEMP t)) = condhit_tc t n (X.LE, X.G)
+    | munch_cond (T.BINOP(T.GE, T.CONST n, e1)) = condhit_c e1 n (X.LE, X.G)
+    | munch_cond (T.BINOP(T.GE, e1, T.CONST n)) = condhit_c e1 n (X.GE, X.L)
+    | munch_cond (T.BINOP(T.GE, T.TEMP t, e1)) = condhit_t e1 t (X.LE, X.G)
+    | munch_cond (T.BINOP(T.GE, e1, T.TEMP t)) = condhit_t e1 t (X.GE, X.L)
+    | munch_cond (T.BINOP(T.GE, e1, e2)) = condhit e1 e2 (X.GE, X.L)
+
+    | munch_cond (T.BINOP(T.BE, T.TEMP t, T.CONST n)) = condhit_tc t n (X.BE, X.A)
+    | munch_cond (T.BINOP(T.BE, T.CONST n, T.TEMP t)) = condhit_tc t n (X.AE, X.B)
+    | munch_cond (T.BINOP(T.BE, T.CONST n, e1)) = condhit_c e1 n (X.AE, X.B)
+    | munch_cond (T.BINOP(T.BE, e1, T.CONST n)) = condhit_c e1 n (X.BE, X.A)
+    | munch_cond (T.BINOP(T.BE, T.TEMP t, e1)) = condhit_t e1 t (X.AE, X.B)
+    | munch_cond (T.BINOP(T.BE, e1, T.TEMP t)) = condhit_t e1 t (X.BE, X.A)
+    | munch_cond (T.BINOP(T.BE, e1, e2)) = condhit e1 e2 (X.BE, X.A)
+
+    | munch_cond (T.BINOP(T.LOGOR, e1, e2)) =
         let
-          val t1 = Temp.new ()
+          val (insn1, pos1, neg1) = munch_cond e1
+          val (insn2, pos2, neg2) = munch_cond e2
+          val t1 = (X.TEMP (Temp.new("logor c 1") Tm.Byte), Tm.Byte)
+          val t2 = (X.TEMP (Temp.new("logor c 2") Tm.Byte), Tm.Byte)
+          val l = Label.new ()
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @
-          [X.CMPL(d, X.TEMP t1), X.SETGE(d), X.MOVZBL(d, d)]
+          if (TU.effect e2 orelse (length insn2 > 10))
+          then ((insn1) @
+                [X.SETcc (pos1, t1), X.Jcc (pos1, l)] @
+                (insn2) @
+                [X.SETcc (pos2, t1), X.LABEL l, X.TEST(t1, t1)],
+                X.NE, X.E)
+          else (insn1 @ [X.SETcc (pos1, t1)] @ insn2 @ [X.SETcc (pos2, t2), X.OR(t1, t2)], X.NE, X.E)
         end
-    | munch_exp d (T.BINOP(T.GT, e1, e2)) =
+    | munch_cond (T.BINOP(T.LOGAND, e1, e2)) =
         let
-          val t1 = Temp.new ()
+          val (insn1, pos1, neg1) = munch_cond e1
+          val (insn2, pos2, neg2) = munch_cond e2
+          val t1 = (X.TEMP (Temp.new("logand c 1") Tm.Byte), Tm.Byte)
+          val t2 = (X.TEMP (Temp.new("logand c 2") Tm.Byte), Tm.Byte)
+          val l = Label.new ()
         in
-          (munch_exp d e1) @ (munch_exp (X.TEMP t1) e2) @
-          [X.CMPL(d, X.TEMP t1), X.SETG(d), X.MOVZBL(d, d)]
+          if (TU.effect e2 orelse (length insn2 > 10))
+          then ((insn1) @
+                [X.SETcc (pos1, t1), X.Jcc (neg1, l)] @
+                (insn2) @
+                [X.SETcc (pos2, t1), X.LABEL l, X.TEST(t1, t1)],
+                X.NE, X.E)
+          else (insn1 @ [X.SETcc (pos1, t1)] @ insn2 @ [X.SETcc (pos2, t2), X.AND(t1, t2)], X.NE, X.E)
         end
-    | munch_exp d (T.UNOP(T.NEG, e1)) = (munch_exp d e1) @ [X.NEG d]
-    | munch_exp d (T.UNOP(T.BITNOT, e1)) = (munch_exp d e1) @ [X.NOTL d]
-    | munch_exp d (T.UNOP(T.BANG, e1)) = (munch_exp d e1) @
-                                         [X.TEST(d,d), X.SETE(d), X.MOVZBL(d, d)]
+    | munch_cond e =
+      let
+        val t = X.TEMP (Temp.new ("munch c") Tm.Long)
+        val (i, s) = munch_exp t e
+      in
+        (i @ [ X.TEST ((t,s),(t,s)) ], X.NE, X.E)
+      end
+
+  (* munch_lval : T.exp -> (X.insn list * X.operand)
+   * Takes an expression that has been typechecked as being a valid lvalue, and then returns an instruction list and an operand to store your shit in.
+   *)
+  and munch_lval (T.TEMP t) = ([], (X.TEMP t, Tm.size t))
+    | munch_lval (T.MEMORY (m,s)) = 
+      let
+        val t = X.TEMP (Tm.new "lv addr" Tm.Quad)
+        val (i,s') = munch_exp t m
+      in
+        (i, (X.REL ((t, Tm.Quad), (X.CONST 0w0, Tm.Quad), 0w1), s))
+      end
+    | munch_lval _ = raise ErrorMsg.InternalError "That wasn't really a valid lvalue..."
 
   (* munch_stm : T.stm -> X.insn list *)
   (* munch_stm stm generates code to execute stm *)
-  fun munch_stm (T.MOVE(T.TEMP(t1), e2)) =
+  and munch_stm (T.MOVE (T.TEMP t1, T.TEMP t2)) = if Tm.size t1 = Tm.size t2 then [X.MOV((X.TEMP t1, Tm.size t1), (X.TEMP t2, Tm.size t2))]
+                                                                             else raise ErrorMsg.InternalError "temp to temp move fuxed."
+    | munch_stm (T.MOVE (T.TEMP t, T.CONST n)) = if Tm.size t = Tm.Long then [X.MOV((X.TEMP t, Tm.size t), (X.CONST n, Tm.size t))]
+                                                                        else raise ErrorMsg.InternalError "const to temp move fuxed."
+    | munch_stm (T.MOVE (T.TEMP t, a as T.ARG (an, sz))) =
+        let
+          val (i, s) = munch_exp (X.TEMP t) a
+        in
+          if s = Tm.size t
+          then i
+          else raise ErrorMsg.InternalError "arg to tmp fuxed."
+        end
+    | munch_stm (T.MOVE (T.TEMP t, a as T.CALL _)) = let val (i, _) = munch_exp (X.TEMP t) a in i end
+    | munch_stm (T.MOVE (a, e2)) =
         let
-          val t = Temp.new ()
+          val t = X.TEMP (Temp.new ("assign") Tm.Long)
+          val (m, (r,s1)) = munch_lval a
+          val (i, s2) = munch_exp t e2
+(*          val _ = print ("move: size " ^ Tm.sfx s2 ^ " from " ^ TU.Print.pp_exp e2 ^ ", " ^ Tm.sfx s1 ^ " from " ^ TU.Print.pp_exp a ^ "\n") *)
+          val _ = if s1 = s2 then () else raise ErrorMsg.InternalError "move generic fuxed."
         in
-          munch_exp (X.TEMP t) e2
-          @ [X.MOVL(X.TEMP t1, X.TEMP t)]
+          m @ i @ [X.MOV((r,s1), (t,s2))]
         end
-    | munch_stm (T.MOVE(_, _)) =
-        raise ErrorMsg.InternalError "Incorrect first operand for T.MOVE?"
-    | munch_stm (T.RETURN(e)) =
+    | munch_stm (T.RETURN(e, sz)) =
         let
-          val t = Temp.new ()
+          val t = X.TEMP (Temp.new ("retval") sz)
+          val (i, s) = munch_exp t e
         in
-          munch_exp (X.TEMP t) e
-          @ [X.MOVL(X.REG X.EAX, X.TEMP t), X.RET]
+          i @ [X.MOV((X.REG X.EAX, sz), (t, if sz = s then sz else raise ErrorMsg.InternalError "retfuxed.")), X.RET]
         end
-    | munch_stm (T.LABEL(l)) = [X.LABEL l]
-    | munch_stm (T.JUMP(l)) = [X.JMP l]
+    | munch_stm (T.LABEL l) = [X.LABEL l]
+    | munch_stm (T.JUMP l) = [X.JMP l]
     | munch_stm (T.JUMPIFN(e, l)) =
        let
-         val t = Temp.new ()
+         val (insns, pos, neg) = munch_cond e 
        in
-         munch_exp (X.TEMP t) e
-         @ [X.TEST(X.TEMP t, X.TEMP t), X.JE l]
+         insns @ [X.Jcc (neg, l)]
        end
+    | munch_stm (T.EFFECT exp) = let val t = X.TEMP (Temp.new "throwaway" Tm.Quad) val (i, _) = munch_exp t exp in i end
 
   fun codegen nil = nil
     | codegen (stm::stms) = munch_stm stm @ codegen stms