Library Machregs

Require Import Coqlib.
Require Import Maps.
Require Import AST.

Machine registers
The following type defines the machine registers that can be referenced as locations. These include:
  • Integer registers that can be allocated to RTL pseudo-registers (Rxx).
  • Floating-point registers that can be allocated to RTL pseudo-registers (Fxx).
  • Two integer registers, not allocatable, reserved as temporaries for spilling and reloading (IT1, IT2).
  • Two float registers, not allocatable, reserved as temporaries for spilling and reloading (FT1, FT2).


The type mreg does not include special-purpose or reserved machine registers such as the stack pointer and the condition codes.

Inductive mreg: Type :=
  
Allocatable integer regs
  | R3: mreg | R4: mreg | R5: mreg | R6: mreg
  | R7: mreg | R8: mreg | R9: mreg | R10: mreg
  | R14: mreg | R15: mreg | R16: mreg
  | R17: mreg | R18: mreg | R19: mreg | R20: mreg
  | R21: mreg | R22: mreg | R23: mreg | R24: mreg
  | R25: mreg | R26: mreg | R27: mreg | R28: mreg
  | R29: mreg | R30: mreg | R31: mreg
  
Allocatable float regs
  | F1: mreg | F2: mreg | F3: mreg | F4: mreg
  | F5: mreg | F6: mreg | F7: mreg | F8: mreg
  | F9: mreg | F10: mreg | F14: mreg | F15: mreg
  | F16: mreg | F17: mreg | F18: mreg | F19: mreg
  | F20: mreg | F21: mreg | F22: mreg | F23: mreg
  | F24: mreg | F25: mreg | F26: mreg | F27: mreg
  | F28: mreg | F29: mreg | F30: mreg | F31: mreg
  
Integer temporaries
  | IT1: mreg | IT2: mreg   
Float temporaries
  | FT1: mreg | FT2: mreg | FT3: mreg .

Lemma mreg_eq: forall (r1 r2: mreg), {r1 = r2} + {r1 <> r2}.


Definition mreg_type (r: mreg): typ :=
  match r with
  | R3 => Tint | R4 => Tint | R5 => Tint | R6 => Tint
  | R7 => Tint | R8 => Tint | R9 => Tint | R10 => Tint
  | R14 => Tint | R15 => Tint | R16 => Tint
  | R17 => Tint | R18 => Tint | R19 => Tint | R20 => Tint
  | R21 => Tint | R22 => Tint | R23 => Tint | R24 => Tint
  | R25 => Tint | R26 => Tint | R27 => Tint | R28 => Tint
  | R29 => Tint | R30 => Tint | R31 => Tint
  | F1 => Tfloat | F2 => Tfloat | F3 => Tfloat | F4 => Tfloat
  | F5 => Tfloat | F6 => Tfloat | F7 => Tfloat | F8 => Tfloat
  | F9 => Tfloat | F10 => Tfloat | F14 => Tfloat | F15 => Tfloat
  | F16 => Tfloat | F17 => Tfloat | F18 => Tfloat | F19 => Tfloat
  | F20 => Tfloat | F21 => Tfloat | F22 => Tfloat | F23 => Tfloat
  | F24 => Tfloat | F25 => Tfloat | F26 => Tfloat | F27 => Tfloat
  | F28 => Tfloat | F29 => Tfloat | F30 => Tfloat | F31 => Tfloat
  | IT1 => Tint | IT2 => Tint
  | FT1 => Tfloat | FT2 => Tfloat | FT3 => Tfloat
  end.

Open Scope positive_scope.

Module IndexedMreg <: INDEXED_TYPE.
  Definition t := mreg.
  Definition eq := mreg_eq.
  Definition index (r: mreg): positive :=
    match r with
    | R3 => 1 | R4 => 2 | R5 => 3 | R6 => 4
    | R7 => 5 | R8 => 6 | R9 => 7 | R10 => 8
    | R14 => 9 | R15 => 10 | R16 => 11
    | R17 => 12 | R18 => 13 | R19 => 14 | R20 => 15
    | R21 => 16 | R22 => 17 | R23 => 18 | R24 => 19
    | R25 => 20 | R26 => 21 | R27 => 22 | R28 => 23
    | R29 => 24 | R30 => 25 | R31 => 26
    | F1 => 28 | F2 => 29 | F3 => 30 | F4 => 31
    | F5 => 32 | F6 => 33 | F7 => 34 | F8 => 35
    | F9 => 36 | F10 => 37 | F14 => 38 | F15 => 39
    | F16 => 40 | F17 => 41 | F18 => 42 | F19 => 43
    | F20 => 44 | F21 => 45 | F22 => 46 | F23 => 47
    | F24 => 48 | F25 => 49 | F26 => 50 | F27 => 51
    | F28 => 52 | F29 => 53 | F30 => 54 | F31 => 55
    | IT1 => 56 | IT2 => 57
    | FT1 => 58 | FT2 => 59 | FT3 => 60
    end.
  Lemma index_inj:
    forall r1 r2, index r1 = index r2 -> r1 = r2.
  
End IndexedMreg.