core/vm: EIP-2315, JUMPSUB for the EVM (#20619)

* core/vm: implement EIP 2315, subroutines for the EVM

* core/vm: eip 2315 - lintfix + check jump dest validity + check ret stack size constraints

  logger: markdown-friendly traces, validate jumpdest, more testcase, correct opcodes

* core/vm: update subroutines acc to eip: disallow walk-into

* core/vm/eips: gas cost changes for subroutines

* core/vm: update opcodes for EIP-2315

* core/vm: define RETURNSUB as a 'jumping' operation + review concerns

Co-authored-by: Martin Holst Swende <martin@swende.se>

core/vm/eips.go

@@ -33,6 +33,8 @@ func EnableEIP(eipNum int, jt *JumpTable) error {
 		enable1884(jt)
 	case 1344:
 		enable1344(jt)
+	case 2315:
+		enable2315(jt)
 	default:
 		return fmt.Errorf("undefined eip %d", eipNum)
 	}
@@ -91,3 +93,34 @@ func enable2200(jt *JumpTable) {
 	jt[SLOAD].constantGas = params.SloadGasEIP2200
 	jt[SSTORE].dynamicGas = gasSStoreEIP2200
 }
+
+// enable2315 applies EIP-2315 (Simple Subroutines)
+// - Adds opcodes that jump to and return from subroutines
+func enable2315(jt *JumpTable) {
+	// New opcode
+	jt[BEGINSUB] = operation{
+		execute:     opBeginSub,
+		constantGas: GasQuickStep,
+		minStack:    minStack(0, 0),
+		maxStack:    maxStack(0, 0),
+		valid:       true,
+	}
+	// New opcode
+	jt[JUMPSUB] = operation{
+		execute:     opJumpSub,
+		constantGas: GasSlowStep,
+		minStack:    minStack(1, 0),
+		maxStack:    maxStack(1, 0),
+		jumps:       true,
+		valid:       true,
+	}
+	// New opcode
+	jt[RETURNSUB] = operation{
+		execute:     opReturnSub,
+		constantGas: GasFastStep,
+		minStack:    minStack(0, 0),
+		maxStack:    maxStack(0, 0),
+		valid:       true,
+		jumps:       true,
+	}
+}