core/vm: fixes due to rebase and removed hardcoded fork schedule in genspec

core/vm/gascosts.go

@@ -84,8 +84,8 @@ func (g *GasBudget) Charge(cost GasCosts) (GasBudget, bool) {
 	return prior, ok
 }
 
-// chargeRegularOnly deducts a regular-only cost.
-func (g *GasBudget) chargeRegularOnly(r uint64) error {
+// ChargeRegularOnly deducts a regular-only cost.
+func (g *GasBudget) ChargeRegularOnly(r uint64) error {
 	if g.RegularGas < r {
 		return ErrOutOfGas
 	}

core/vm/gen/gen.go

@@ -113,7 +113,7 @@ func (g *generator) p(format string, args ...any) {
 // parseHandlers parses instructions.go, eips.go, stack.go, gascosts.go and
 // interpreter.go. It returns the top-level opXxx handlers by name, the
 // //gen:inline *Stack helper methods, and the gas/memory helper functions
-// (chargeRegularOnly, computeMemorySize, chargeDynamicGas) whose bodies are
+// (ChargeRegularOnly, computeMemorySize, chargeDynamicGas) whose bodies are
 // spliced into the generated dispatch (all by name).
 func parseHandlers(vmDir string) (fset *token.FileSet, opcodeHandlers, stackHelpers, gasHelpers map[string]*ast.FuncDecl) {
 	fset = token.NewFileSet()
@@ -132,7 +132,7 @@ func parseHandlers(vmDir string) (fset *token.FileSet, opcodeHandlers, stackHelp
 				continue
 			}
 			switch {
-			case fn.Name.Name == "chargeRegularOnly" || fn.Name.Name == "computeMemorySize" || fn.Name.Name == "chargeDynamicGas" || fn.Name.Name == "chargeVerkleCodeChunkGas": // spliced gas/memory helpers
+			case fn.Name.Name == "ChargeRegularOnly" || fn.Name.Name == "computeMemorySize" || fn.Name.Name == "chargeDynamicGas" || fn.Name.Name == "chargeVerkleCodeChunkGas": // spliced gas/memory helpers
 				gasHelpers[fn.Name.Name] = fn
 			case fn.Recv == nil: // top-level opXxx handler
 				opcodeHandlers[fn.Name.Name] = fn
@@ -627,7 +627,7 @@ func (g *generator) generateStackChecks(minExpr, maxExpr any, under, over bool)
 }
 
 // generateStaticGas returns the static-gas charge, spliced call-free from the
-// chargeRegularOnly body for amount: a constant on the inlined and
+// ChargeRegularOnly body for amount: a constant on the inlined and
 // direct-call paths, operation.constantGas in the table path. The receiver maps
 // to contract.Gas and the method's single uint64 parameter to amount, substituted
 // textually on word boundaries (which cannot touch fields like RegularGas). Its
@@ -635,13 +635,13 @@ func (g *generator) generateStackChecks(minExpr, maxExpr any, under, over bool)
 // is dropped so the opcode falls through to its remaining steps (see
 // rewriteGasReturns).
 func (g *generator) generateStaticGas(amount any) string {
-	fn := g.gasHelpers["chargeRegularOnly"]
+	fn := g.gasHelpers["ChargeRegularOnly"]
 	if fn == nil {
-		fatalf("no chargeRegularOnly gas helper to inline")
+		fatalf("no ChargeRegularOnly gas helper to inline")
 	}
 	names := paramNames(fn)
 	if len(names) != 1 {
-		fatalf("chargeRegularOnly takes %d params, want 1", len(names))
+		fatalf("ChargeRegularOnly takes %d params, want 1", len(names))
 	}
 	src := g.renderAst(fn.Body.List)
 	src = regexp.MustCompile(`\b`+recvName(fn)+`\b`).ReplaceAllString(src, "contract.Gas")

core/vm/genspec.go

@@ -22,6 +22,8 @@ import (
 	"reflect"
 	"runtime"
 	"strings"
+
+	"github.com/ethereum/go-ethereum/params"
 )
 
 // This file exposes the interpreter's opcode metadata to the code generator in
@@ -56,35 +58,13 @@ type GenFork struct {
 	Ops       [256]GenOp
 }
 
-// genForkOrder is the canonical fork progression for code generation, oldest to
-// newest, each paired with the params.Rules field that activates it.
-//
-// Petersburg is omitted: it shares Constantinople's opcode set and only changes
-// SSTORE dynamic gas, which flows through the shared gas function. Verkle/UBT is
-// omitted: over its Shanghai base it adds no new opcodes (it only swaps gas and
-// execute on existing opcodes), which the generated switch picks up from the
-// active table at runtime.
-var genForkOrder = []struct {
-	name string
-	rule string
-	set  *JumpTable
-}{
-	{"Frontier", "", &frontierInstructionSet},
-	{"Homestead", "IsHomestead", &homesteadInstructionSet},
-	{"TangerineWhistle", "IsEIP150", &tangerineWhistleInstructionSet},
-	{"SpuriousDragon", "IsEIP158", &spuriousDragonInstructionSet},
-	{"Byzantium", "IsByzantium", &byzantiumInstructionSet},
-	{"Constantinople", "IsConstantinople", &constantinopleInstructionSet},
-	{"Istanbul", "IsIstanbul", &istanbulInstructionSet},
-	{"Berlin", "IsBerlin", &berlinInstructionSet},
-	{"London", "IsLondon", &londonInstructionSet},
-	{"Merge", "IsMerge", &mergeInstructionSet},
-	{"Shanghai", "IsShanghai", &shanghaiInstructionSet},
-	{"Cancun", "IsCancun", &cancunInstructionSet},
-	{"Prague", "IsPrague", &pragueInstructionSet},
-	{"Osaka", "IsOsaka", &osakaInstructionSet},
-	{"Amsterdam", "IsAmsterdam", &amsterdamInstructionSet},
-}
+// codegenSkippedForks are forks in geth's fork schedule that the generator does
+// not give a lane. Verkle/UBT is the only one: over its Shanghai base it adds no
+// opcodes, it only swaps gas and execute functions on existing ones (enable4762),
+// which the generated switch picks up from the active table at runtime. Emitting
+// a lane for it would trip the generator's fork-stability check (an inlined op's
+// execute function is not allowed to vary by fork).
+var codegenSkippedForks = map[string]bool{"IsUBT": true}
 
 // genFnName returns the FuncForPC name of a jump-table function value with the
 // package path stripped (e.g. "gasKeccak256"), or "" if nil. An aliased var
@@ -108,28 +88,75 @@ func genFnName(fn any) string {
 }
 
 // GenForks returns per-fork opcode metadata for the interpreter code generator
-// (core/vm/gen). It is exported solely for that purpose.
+// (core/vm/gen), one entry per fork that changes the opcode table, oldest to
+// newest. It derives the progression from params.Rules and LookupInstructionSet
+// (in params.Rules declaration order, which is chronological) so new forks are
+// picked up without restating a list here.
 func GenForks() []GenFork {
-	out := make([]GenFork, len(genForkOrder))
-	for i, f := range genForkOrder {
-		gf := GenFork{Name: f.name, RuleField: f.rule}
-		for code := range 256 {
-			op := f.set[code]
-			if op == nil || op.undefined {
-				continue
-			}
-			gf.Ops[code] = GenOp{
-				Name:         OpCode(code).String(),
-				Defined:      true,
-				ConstantGas:  op.constantGas,
-				MinStack:     op.minStack,
-				MaxStack:     op.maxStack,
-				ExecuteFn:    genFnName(op.execute),
-				DynamicGasFn: genFnName(op.dynamicGas),
-				MemorySizeFn: genFnName(op.memorySize),
-			}
+	// Frontier is always active and carries no rule gate.
+	frontier, _ := LookupInstructionSet(params.Rules{})
+	out := []GenFork{genFork("Frontier", "", &frontier)}
+
+	rt := reflect.TypeOf(params.Rules{})
+	for i := range rt.NumField() {
+		field := rt.Field(i)
+		if field.Type.Kind() != reflect.Bool || codegenSkippedForks[field.Name] {
+			continue
 		}
-		out[i] = gf
+		// Activate only this field so the fork resolves to the table it gates.
+		var rules params.Rules
+		reflect.ValueOf(&rules).Elem().Field(i).SetBool(true)
+		set, _ := LookupInstructionSet(rules)
+		if sameOps(&set, &frontier) {
+			continue // this rule does not change the opcode table
+		}
+		out = append(out, genFork(strings.TrimPrefix(field.Name, "Is"), field.Name, &set))
 	}
 	return out
 }
+
+// genFork extracts the generator-facing per-opcode metadata from one fork's
+// instruction set.
+func genFork(name, rule string, set *JumpTable) GenFork {
+	gf := GenFork{Name: name, RuleField: rule}
+	for code := range 256 {
+		op := set[code]
+		if op == nil || op.undefined {
+			continue
+		}
+		gf.Ops[code] = GenOp{
+			Name:         OpCode(code).String(),
+			Defined:      true,
+			ConstantGas:  op.constantGas,
+			MinStack:     op.minStack,
+			MaxStack:     op.maxStack,
+			ExecuteFn:    genFnName(op.execute),
+			DynamicGasFn: genFnName(op.dynamicGas),
+			MemorySizeFn: genFnName(op.memorySize),
+		}
+	}
+	return gf
+}
+
+// sameOps reports whether two instruction sets carry identical per-opcode static
+// metadata: which slots are defined, and their static gas and stack bounds. It
+// is used to tell whether a fork actually changes the opcode table. Handler,
+// dynamic-gas and memory-size functions are ignored (they cannot be compared for
+// equality and are reached through the table at runtime).
+func sameOps(a, b *JumpTable) bool {
+	for code := range 256 {
+		oa, ob := a[code], b[code]
+		undefA := oa == nil || oa.undefined
+		undefB := ob == nil || ob.undefined
+		if undefA != undefB {
+			return false
+		}
+		if undefA {
+			continue
+		}
+		if oa.constantGas != ob.constantGas || oa.minStack != ob.minStack || oa.maxStack != ob.maxStack {
+			return false
+		}
+	}
+	return true
+}

core/vm/interpreter.go

@@ -209,7 +209,7 @@ func (evm *EVM) execTraced(scope *ScopeContext) (ret []byte, err error) {
 			return nil, &ErrStackOverflow{stackLen: sLen, limit: operation.maxStack}
 		}
 		// for tracing: this gas consumption event is emitted below in the debug section.
-		if err := contract.Gas.chargeRegularOnly(cost); err != nil {
+		if err := contract.Gas.ChargeRegularOnly(cost); err != nil {
 			return nil, err
 		}
 
@@ -287,7 +287,7 @@ func (contract *Contract) chargeDynamicGas(operation *operation, evm *EVM, stack
 	// A regular-only deduction when there is no state gas, otherwise the full
 	// multidimensional charge through the reservoir.
 	if dynamicCost.StateGas == 0 {
-		if cerr := contract.Gas.chargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
+		if cerr := contract.Gas.ChargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
 			return dynamicCost, cerr
 		}
 	} else if !contract.Gas.charge(dynamicCost) {

core/vm/interpreter_gen.go

@@ -601,7 +601,7 @@ mainLoop:
 				break mainLoop
 			}
 			if dynamicCost.StateGas == 0 {
-				if cerr := contract.Gas.chargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
+				if cerr := contract.Gas.ChargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
 					res, err = nil, cerr
 					break mainLoop
 				}
@@ -664,7 +664,7 @@ mainLoop:
 				break mainLoop
 			}
 			if dynamicCost.StateGas == 0 {
-				if cerr := contract.Gas.chargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
+				if cerr := contract.Gas.ChargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
 					res, err = nil, cerr
 					break mainLoop
 				}
@@ -712,7 +712,7 @@ mainLoop:
 				break mainLoop
 			}
 			if dynamicCost.StateGas == 0 {
-				if cerr := contract.Gas.chargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
+				if cerr := contract.Gas.ChargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
 					res, err = nil, cerr
 					break mainLoop
 				}
@@ -760,7 +760,7 @@ mainLoop:
 				break mainLoop
 			}
 			if dynamicCost.StateGas == 0 {
-				if cerr := contract.Gas.chargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
+				if cerr := contract.Gas.ChargeRegularOnly(dynamicCost.RegularGas); cerr != nil {
 					res, err = nil, cerr
 					break mainLoop
 				}