neoneo-go/pkg/compiler/debug.go
Evgenii Stratonikov 5d3da26e1e compiler: support sequence points in debug info
Sequence points is a way to map a specific instruction offset
from a compiled contract to a text span in a source file.

This commit implements mapping only for `return` statements.
Further improvements are straight-forward.
2020-04-06 15:30:07 +03:00

256 lines
6.5 KiB
Go

package compiler
import (
"encoding/json"
"errors"
"fmt"
"go/ast"
"go/types"
"strconv"
"strings"
)
// DebugInfo represents smart-contract debug information.
type DebugInfo struct {
EntryPoint string `json:"entrypoint"`
Documents []string `json:"documents"`
Methods []MethodDebugInfo `json:"methods"`
Events []EventDebugInfo `json:"events"`
}
// MethodDebugInfo represents smart-contract's method debug information.
type MethodDebugInfo struct {
ID string `json:"id"`
// Name is the name of the method together with the namespace it belongs to.
Name DebugMethodName `json:"name"`
// Range is the range of smart-contract's opcodes corresponding to the method.
Range DebugRange `json:"range"`
// Parameters is a list of method's parameters.
Parameters []DebugParam `json:"params"`
// ReturnType is method's return type.
ReturnType string `json:"return-type"`
Variables []string `json:"variables"`
// SeqPoints is a map between source lines and byte-code instruction offsets.
SeqPoints []DebugSeqPoint `json:"sequence-points"`
}
// DebugMethodName is a combination of a namespace and name.
type DebugMethodName struct {
Namespace string
Name string
}
// EventDebugInfo represents smart-contract's event debug information.
type EventDebugInfo struct {
ID string `json:"id"`
// Name is a human-readable event name in a format "{namespace}-{name}".
Name string `json:"name"`
Parameters []DebugParam `json:"parameters"`
}
// DebugSeqPoint represents break-point for debugger.
type DebugSeqPoint struct {
// Opcode is an opcode's address.
Opcode int
// Document is an index of file where sequence point occurs.
Document int
// StartLine is the first line of the break-pointed statement.
StartLine int
// StartCol is the first column of the break-pointed statement.
StartCol int
// EndLine is the last line of the break-pointed statement.
EndLine int
// EndCol is the last column of the break-pointed statement.
EndCol int
}
// DebugRange represents method's section in bytecode.
type DebugRange struct {
Start uint16
End uint16
}
// DebugParam represents variables's name and type.
type DebugParam struct {
Name string
Type string
}
func (c *codegen) saveSequencePoint(n ast.Node) {
fset := c.buildInfo.program.Fset
start := fset.Position(n.Pos())
end := fset.Position(n.End())
c.sequencePoints[c.scope.name] = append(c.sequencePoints[c.scope.name], DebugSeqPoint{
Opcode: c.prog.Len(),
StartLine: start.Line,
StartCol: start.Offset,
EndLine: end.Line,
EndCol: end.Offset,
})
}
func (c *codegen) emitDebugInfo() *DebugInfo {
d := &DebugInfo{
EntryPoint: mainIdent,
Events: []EventDebugInfo{},
}
for name, scope := range c.funcs {
m := c.methodInfoFromScope(name, scope)
if m.Range.Start == m.Range.End {
continue
}
d.Methods = append(d.Methods, *m)
}
return d
}
func (c *codegen) methodInfoFromScope(name string, scope *funcScope) *MethodDebugInfo {
ps := scope.decl.Type.Params
params := make([]DebugParam, 0, ps.NumFields())
for i := range params {
for j := range ps.List[i].Names {
params = append(params, DebugParam{
Name: ps.List[i].Names[j].Name,
Type: c.scTypeFromExpr(ps.List[i].Type),
})
}
}
return &MethodDebugInfo{
ID: name,
Name: DebugMethodName{Name: name},
Range: scope.rng,
Parameters: params,
ReturnType: c.scReturnTypeFromScope(scope),
SeqPoints: c.sequencePoints[name],
}
}
func (c *codegen) scReturnTypeFromScope(scope *funcScope) string {
results := scope.decl.Type.Results
switch results.NumFields() {
case 0:
return "Void"
case 1:
return c.scTypeFromExpr(results.List[0].Type)
default:
// multiple return values are not supported in debugger
return "Any"
}
}
func (c *codegen) scTypeFromExpr(typ ast.Expr) string {
switch t := c.typeInfo.Types[typ].Type.(type) {
case *types.Basic:
info := t.Info()
switch {
case info&types.IsInteger != 0:
return "Integer"
case info&types.IsBoolean != 0:
return "Boolean"
case info&types.IsString != 0:
return "String"
default:
return "Any"
}
case *types.Map:
return "Map"
case *types.Struct:
return "Struct"
case *types.Slice:
if isByteArrayType(t) {
return "ByteArray"
}
return "Array"
default:
return "Any"
}
}
// MarshalJSON implements json.Marshaler interface.
func (d *DebugRange) MarshalJSON() ([]byte, error) {
return []byte(`"` + strconv.FormatUint(uint64(d.Start), 10) + `-` +
strconv.FormatUint(uint64(d.End), 10) + `"`), nil
}
// UnmarshalJSON implements json.Unmarshaler interface.
func (d *DebugRange) UnmarshalJSON(data []byte) error {
startS, endS, err := parsePairJSON(data, "-")
if err != nil {
return err
}
start, err := strconv.ParseUint(startS, 10, 16)
if err != nil {
return err
}
end, err := strconv.ParseUint(endS, 10, 16)
if err != nil {
return err
}
d.Start = uint16(start)
d.End = uint16(end)
return nil
}
// MarshalJSON implements json.Marshaler interface.
func (d *DebugParam) MarshalJSON() ([]byte, error) {
return []byte(`"` + d.Name + `,` + d.Type + `"`), nil
}
// UnmarshalJSON implements json.Unmarshaler interface.
func (d *DebugParam) UnmarshalJSON(data []byte) error {
startS, endS, err := parsePairJSON(data, ",")
if err != nil {
return err
}
d.Name = startS
d.Type = endS
return nil
}
// MarshalJSON implements json.Marshaler interface.
func (d *DebugMethodName) MarshalJSON() ([]byte, error) {
return []byte(`"` + d.Namespace + `,` + d.Name + `"`), nil
}
// UnmarshalJSON implements json.Unmarshaler interface.
func (d *DebugMethodName) UnmarshalJSON(data []byte) error {
startS, endS, err := parsePairJSON(data, ",")
if err != nil {
return err
}
d.Namespace = startS
d.Name = endS
return nil
}
// MarshalJSON implements json.Marshaler interface.
func (d *DebugSeqPoint) MarshalJSON() ([]byte, error) {
s := fmt.Sprintf("%d[%d]%d:%d-%d:%d", d.Opcode, d.Document,
d.StartLine, d.StartCol, d.EndLine, d.EndCol)
return []byte(`"` + s + `"`), nil
}
// UnmarshalJSON implements json.Unmarshaler interface.
func (d *DebugSeqPoint) UnmarshalJSON(data []byte) error {
_, err := fmt.Sscanf(string(data), `"%d[%d]%d:%d-%d:%d"`,
&d.Opcode, &d.Document, &d.StartLine, &d.StartCol, &d.EndLine, &d.EndCol)
return err
}
func parsePairJSON(data []byte, sep string) (string, string, error) {
var s string
if err := json.Unmarshal(data, &s); err != nil {
return "", "", err
}
ss := strings.SplitN(s, sep, 2)
if len(ss) != 2 {
return "", "", errors.New("invalid range format")
}
return ss[0], ss[1], nil
}