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Dmitry Boulytchev 2018-03-07 10:13:34 +03:00
parent 06fb783c80
commit 0561c22217
1 changed files with 17 additions and 15 deletions
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30
src/X86.ml
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@ -13,8 +13,8 @@ let word_size = 4
type opnd =
| R of int (* hard register *)
| S of int (* a position on the hardware stack *)
| M of string (* named memory location *)
| L of int (* immediate operand *)
| M of string (* a named memory location *)
| L of int (* an immediate operand *)
(* For convenience we define the following synonyms for the registers: *)
let ebx = R 0
@ -28,15 +28,18 @@ let esp = R 7
(* Now x86 instruction (we do not need all of them): *)
type instr =
| Cltd
| Set of string * string
| IDiv of opnd
| Binop of string * opnd * opnd
| Mov of opnd * opnd
| Push of opnd
| Pop of opnd
| Ret
| Call of string
(* copies a value from the first to the second operand *) | Mov of opnd * opnd
(* makes a binary operation; note, the first operand *) | Binop of string * opnd * opnd
(* designates x86 operator, not the source language one *)
(* x86 integer division, see instruction set reference *) | IDiv of opnd
(* see instruction set reference *) | Cltd
(* sets a value from flags; the first operand is the *) | Set of string * string
(* suffix, which determines the value being set, the *)
(* the second --- (sub)register name *)
(* pushes the operand on the hardware stack *) | Push of opnd
(* pops from the hardware stack to the operand *) | Pop of opnd
(* call a function by a name *) | Call of string
(* returns from a function *) | Ret
(* Instruction printer *)
let show instr =
@ -74,7 +77,7 @@ open SM
compile : env -> prg -> env * instr list
Take an environment, a stack machine program, and returns a pair --- updated environment and the list
Take an environment, a stack machine program, and returns a pair --- the updated environment and the list
of x86 instructions
*)
let compile env code =
@ -131,7 +134,7 @@ let compile env code =
| "<" | "<=" | "==" | "!=" | ">=" | ">" ->
(match x with
| M _ | S _ ->
[Binop ("^" , eax, eax);
[Binop ("^", eax, eax);
Mov (x, edx);
Binop ("cmp", edx, y);
Set (suffix op, "%al");
@ -185,7 +188,6 @@ let compile env code =
(* A set of strings *)
module S = Set.Make (String)
(* Environment implementation *)
class env =
object (self)