Add RETD opcode (#19)

fuel-asm/src/opcode.rs

@@ -552,6 +552,31 @@ pub enum Opcode {
  /// 1. `$pc = $pc + 4` (advance program counter from where we called)
  RET(RegisterId),
 
+ /// Return from context with data
+ ///
+ /// | Operation | ```returndata($rA, $rB);```
+ /// | Syntax | `retd $rA, $rB`
+ /// | Encoding | `0x00 rA rB - -`
+ ///
+ /// If current context is external, cease VM execution and return `MEM[$rA, $rB]`.
+ ///
+ /// Returns from contract call, popping the call frame. Before popping:
+ ///
+ /// 1. Return the unused forwarded gas to the caller:
+ /// - `$cgas = $cgas + $fp->$cgas` (add remaining context gas from
+ /// previous context to current remaining context gas)
+ ///
+ /// Then pop the call frame and restoring registers _except_ `$ggas` and
+ /// `$cgas`. Afterwards, set the following registers:
+ ///
+ /// Set the return value:
+ ///
+ /// 1. `$ret = $rA`
+ /// 1. `$retl = $rB`
+ ///
+ /// 1. `$pc = $pc + 4` (advance program counter from where we called)
+ RETD(RegisterId, RegisterId),
+
  /// Extend the current call frame's stack by an immediate value.
  ///
  /// | Operation | ```$sp = $sp + imm```
@@ -1271,6 +1296,7 @@ impl Opcode {
  OpcodeRepr::JI => Opcode::JI(imm24),
  OpcodeRepr::JNEI => Opcode::JNEI(ra, rb, imm12),
  OpcodeRepr::RET => Opcode::RET(ra),
+ OpcodeRepr::RETD => Opcode::RETD(ra, rb),
  OpcodeRepr::CFEI => Opcode::CFEI(imm24),
  OpcodeRepr::CFSI => Opcode::CFSI(imm24),
  OpcodeRepr::LB => Opcode::LB(ra, rb, imm12),
@@ -1375,6 +1401,7 @@ impl Opcode {
  Self::JI(_) => [None; 4],
  Self::JNEI(ra, rb, _) => [Some(*ra), Some(*rb), None, None],
  Self::RET(ra) => [Some(*ra), None, None, None],
+ Self::RETD(ra, rb) => [Some(*ra), Some(*rb), None, None],
  Self::CFEI(_) => [None; 4],
  Self::CFSI(_) => [None; 4],
  Self::LB(ra, rb, _) => [Some(*ra), Some(*rb), None, None],
@@ -1648,6 +1675,9 @@ impl From<Opcode> for u32 {
  | (imm12 as u32)
  }
  Opcode::RET(ra) => ((OpcodeRepr::RET as u32) << 24) | ((ra as u32) << 18),
+ Opcode::RETD(ra, rb) => {
+ ((OpcodeRepr::RETD as u32) << 24) | ((ra as u32) << 18) | ((rb as u32) << 12)
+ }
  Opcode::CFEI(imm24) => ((OpcodeRepr::CFEI as u32) << 24) | (imm24 as u32),
  Opcode::CFSI(imm24) => ((OpcodeRepr::CFSI as u32) << 24) | (imm24 as u32),
  Opcode::LB(ra, rb, imm12) => {

fuel-asm/src/opcode/consts.rs

@@ -35,6 +35,7 @@ pub enum OpcodeRepr {
  JI = 0x32,
  JNEI = 0x33,
  RET = 0x34,
+ RETD = 0x35,
  CFEI = 0x40,
  CFSI = 0x41,
  LB = 0x42,
@@ -124,6 +125,7 @@ impl OpcodeRepr {
  0x32 => Self::JI,
  0x33 => Self::JNEI,
  0x34 => Self::RET,
+ 0x35 => Self::RETD,
  0x40 => Self::CFEI,
  0x41 => Self::CFSI,
  0x42 => Self::LB,

fuel-asm/tests/encoding.rs

@@ -43,6 +43,7 @@ fn opcode() {
  Opcode::JI(imm24),
  Opcode::JNEI(r, r, imm12),
  Opcode::RET(r),
+ Opcode::RETD(r, r),
  Opcode::CFEI(imm24),
  Opcode::CFSI(imm24),
  Opcode::LB(r, r, imm12),