neoneo-go/pkg/compiler/inline.go
Roman Khimov b57dd2cad6 compiler: properly inline methods, use receiver
Notice that this doesn't differentiate between (*T) and (T) receivers always
treating them as is. But we have the same problem with arguments now and the
number of inlined calls is limited, usually we want this behavior.
2022-07-07 15:10:29 +03:00

250 lines
6.5 KiB
Go

package compiler
import (
"fmt"
"go/ast"
"go/constant"
"go/types"
"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm/emit"
"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
)
// inlineCall inlines call of n for function represented by f.
// Call `f(a,b)` for definition `func f(x,y int)` is translated to block:
// {
// x := a
// y := b
// <inline body of f directly>
// }
func (c *codegen) inlineCall(f *funcScope, n *ast.CallExpr) {
labelSz := len(c.labelList)
offSz := len(c.inlineLabelOffsets)
c.inlineLabelOffsets = append(c.inlineLabelOffsets, labelSz)
defer func() {
c.inlineLabelOffsets = c.inlineLabelOffsets[:offSz]
c.labelList = c.labelList[:labelSz]
}()
pkg := c.packageCache[f.pkg.Path()]
sig := c.typeOf(n.Fun).(*types.Signature)
c.processStdlibCall(f, n.Args)
// When inlined call is used during global initialization
// there is no func scope, thus this if.
if c.scope == nil {
c.scope = &funcScope{}
c.scope.vars.newScope()
defer func() {
if cnt := c.scope.vars.localsCnt; cnt > c.globalInlineCount {
c.globalInlineCount = cnt
}
c.scope = nil
}()
}
// Arguments need to be walked with the current scope,
// while stored in the new.
oldScope := c.scope.vars.locals
c.scope.vars.newScope()
newScope := make([]map[string]varInfo, len(c.scope.vars.locals))
copy(newScope, c.scope.vars.locals)
defer c.scope.vars.dropScope()
if f.decl.Recv != nil {
c.scope.vars.locals = newScope
name := f.decl.Recv.List[0].Names[0].Name
c.scope.vars.addAlias(name, -1, unspecifiedVarIndex, &varContext{
importMap: c.importMap,
expr: f.selector,
scope: oldScope,
})
}
hasVarArgs := !n.Ellipsis.IsValid()
needPack := sig.Variadic() && hasVarArgs
for i := range n.Args {
c.scope.vars.locals = oldScope
// true if normal arg or var arg is `slice...`
needStore := i < sig.Params().Len()-1 || !sig.Variadic() || !hasVarArgs
if !needStore {
break
}
name := sig.Params().At(i).Name()
if !c.hasCalls(n.Args[i]) {
// If argument contains no calls, we save context and traverse the expression
// when argument is emitted.
c.scope.vars.locals = newScope
c.scope.vars.addAlias(name, -1, unspecifiedVarIndex, &varContext{
importMap: c.importMap,
expr: n.Args[i],
scope: oldScope,
})
continue
}
ast.Walk(c, n.Args[i])
c.scope.vars.locals = newScope
c.scope.newLocal(name)
c.emitStoreVar("", name)
}
if needPack {
// traverse variadic args and pack them
// if they are provided directly i.e. without `...`
c.scope.vars.locals = oldScope
for i := sig.Params().Len() - 1; i < len(n.Args); i++ {
ast.Walk(c, n.Args[i])
}
c.scope.vars.locals = newScope
c.packVarArgs(n, sig)
name := sig.Params().At(sig.Params().Len() - 1).Name()
c.scope.newLocal(name)
c.emitStoreVar("", name)
}
c.pkgInfoInline = append(c.pkgInfoInline, pkg)
oldMap := c.importMap
oldDefers := c.scope.deferStack
c.scope.deferStack = nil
c.fillImportMap(f.file, pkg)
ast.Inspect(f.decl, c.scope.analyzeVoidCalls)
ast.Walk(c, f.decl.Body)
if c.scope.voidCalls[n] {
for i := 0; i < f.decl.Type.Results.NumFields(); i++ {
emit.Opcodes(c.prog.BinWriter, opcode.DROP)
}
}
c.processDefers()
c.scope.deferStack = oldDefers
c.importMap = oldMap
c.pkgInfoInline = c.pkgInfoInline[:len(c.pkgInfoInline)-1]
}
func (c *codegen) processStdlibCall(f *funcScope, args []ast.Expr) {
if f == nil {
return
}
if f.pkg.Path() == interopPrefix+"/runtime" && (f.name == "Notify" || f.name == "Log") {
c.processNotify(f, args)
}
if f.pkg.Path() == interopPrefix+"/contract" && f.name == "Call" {
c.processContractCall(f, args)
}
}
func (c *codegen) processNotify(f *funcScope, args []ast.Expr) {
if c.scope != nil && c.isVerifyFunc(c.scope.decl) &&
c.scope.pkg == c.mainPkg.Types && (c.buildInfo.options == nil || !c.buildInfo.options.NoEventsCheck) {
c.prog.Err = fmt.Errorf("runtime.%s is not allowed in `Verify`", f.name)
return
}
if f.name == "Log" {
return
}
// Sometimes event name is stored in a var.
// Skip in this case.
tv := c.typeAndValueOf(args[0])
if tv.Value == nil {
return
}
params := make([]string, 0, len(args[1:]))
for _, p := range args[1:] {
st, _, _ := c.scAndVMTypeFromExpr(p)
params = append(params, st.String())
}
name := constant.StringVal(tv.Value)
if len(name) > runtime.MaxEventNameLen {
c.prog.Err = fmt.Errorf("event name '%s' should be less than %d",
name, runtime.MaxEventNameLen)
return
}
c.emittedEvents[name] = append(c.emittedEvents[name], params)
}
func (c *codegen) processContractCall(f *funcScope, args []ast.Expr) {
var u util.Uint160
// For stdlib calls it is `interop.Hash160(constHash)`
// so we can determine hash at compile-time.
ce, ok := args[0].(*ast.CallExpr)
if ok && len(ce.Args) == 1 {
// Ensure this is a type conversion, not a simple invoke.
se, ok := ce.Fun.(*ast.SelectorExpr)
if ok {
name, _ := c.getFuncNameFromSelector(se)
if _, ok := c.funcs[name]; !ok {
value := c.typeAndValueOf(ce.Args[0]).Value
if value != nil {
s := constant.StringVal(value)
copy(u[:], s) // constant must be big-endian
}
}
}
}
value := c.typeAndValueOf(args[1]).Value
if value == nil {
return
}
method := constant.StringVal(value)
value = c.typeAndValueOf(args[2]).Value
if value == nil {
return
}
flag, _ := constant.Uint64Val(value)
c.appendInvokedContract(u, method, flag)
}
func (c *codegen) appendInvokedContract(u util.Uint160, method string, flag uint64) {
currLst := c.invokedContracts[u]
for _, m := range currLst {
if m == method {
return
}
}
if flag&uint64(callflag.WriteStates|callflag.AllowNotify) != 0 {
c.invokedContracts[u] = append(currLst, method)
}
}
// hasCalls returns true if expression contains any calls.
// We uses this as a rough heuristic to determine if expression calculation
// has any side-effects.
func (c *codegen) hasCalls(expr ast.Expr) bool {
var has bool
ast.Inspect(expr, func(n ast.Node) bool {
ce, ok := n.(*ast.CallExpr)
if !has && ok {
isFunc := true
fun, ok := ce.Fun.(*ast.Ident)
if ok {
_, isFunc = c.getFuncFromIdent(fun)
} else {
var sel *ast.SelectorExpr
sel, ok = ce.Fun.(*ast.SelectorExpr)
if ok {
name, _ := c.getFuncNameFromSelector(sel)
_, isFunc = c.funcs[name]
fun = sel.Sel
}
}
has = isFunc || fun.Obj != nil && (fun.Obj.Kind == ast.Var || fun.Obj.Kind == ast.Fun)
}
return !has
})
return has
}