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Localize definedSymbols
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@DQNEO
DQNEO committed Jul 9, 2023
1 parent 1319917 commit e12f109
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Showing 2 changed files with 33 additions and 36 deletions.
4 changes: 2 additions & 2 deletions encoder.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -925,7 +925,7 @@ func encode(s *Stmt) *Instruction {
return instr
}

func encodeData(s *Stmt, dataAddr uintptr) []byte {
func encodeData(s *Stmt, dataAddr uintptr, labeledSymbols map[string]*symbolDefinition) []byte {
defer func() {
if x := recover(); x != nil {
panic(fmt.Sprintf("%s\n[encoder] %s at %s:%d\n\necho '%s' |./encode as",
Expand All @@ -935,7 +935,7 @@ func encodeData(s *Stmt, dataAddr uintptr) []byte {
}()

if s.labelSymbol != "" {
definedSymbols[s.labelSymbol].address = dataAddr
labeledSymbols[s.labelSymbol].address = dataAddr
}
if s.keySymbol == "" {
return nil
Expand Down
65 changes: 31 additions & 34 deletions main.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -296,8 +296,6 @@ type symbolDefinition struct {
instr *Instruction
}

var definedSymbols = make(map[string]*symbolDefinition)

const STT_SECTION = 0x03

func isDataSymbolUsed(definedSymbols map[string]*symbolDefinition, relaTextUsers []*relaTextUser, relaDataUsers []*relaDataUser) bool {
Expand All @@ -321,7 +319,7 @@ func isDataSymbolUsed(definedSymbols map[string]*symbolDefinition, relaTextUsers
return false
}

func buildSymbolTable(addData bool, globalSymbols map[string]bool, symbolsInLexicalOrder []string) (uint32, []uint8, map[string]int) {
func buildSymbolTable(addData bool, globalSymbols map[string]bool, symbolsInLexicalOrder []string, labeledSymbols map[string]*symbolDefinition) (uint32, []uint8, map[string]int) {
//debugf("# Building symbol table ....\n")

var symbolIndex = make(map[string]int)
Expand Down Expand Up @@ -355,7 +353,7 @@ func buildSymbolTable(addData bool, globalSymbols map[string]bool, symbolsInLexi
continue
}
isGlobal := globalSymbols[sym]
_, isDefined := definedSymbols[sym]
_, isDefined := labeledSymbols[sym]
if !isDefined {
isGlobal = true
}
Expand Down Expand Up @@ -385,7 +383,7 @@ func buildSymbolTable(addData bool, globalSymbols map[string]bool, symbolsInLexi

for _, symname := range allSymbolsForElf {
isGlobal := globalSymbols[symname]
sym, isDefined := definedSymbols[symname]
sym, isDefined := labeledSymbols[symname]
var addr uintptr
var shndx uint16
if isDefined {
Expand Down Expand Up @@ -472,10 +470,10 @@ func assert(bol bool, errorMsg string) {
}
}

func resolveVariableLengthInstrs(instrs []*Instruction) []*Instruction {
func resolveVariableLengthInstrs(instrs []*Instruction, labeledSymbols map[string]*symbolDefinition) []*Instruction {
var todos []*Instruction
for _, vr := range instrs {
sym, ok := definedSymbols[vr.varcode.trgtSymbol]
sym, ok := labeledSymbols[vr.varcode.trgtSymbol]
if !ok {
continue
}
Expand Down Expand Up @@ -514,7 +512,7 @@ func resolveVariableLengthInstrs(instrs []*Instruction) []*Instruction {
return todos
}

func encodeAllText(ss []*Stmt) []byte {
func encodeAllText(ss []*Stmt, labeledSymbols map[string]*symbolDefinition) []byte {
var insts []*Instruction
var index int
var first *Instruction
Expand All @@ -527,7 +525,7 @@ func encodeAllText(ss []*Stmt) []byte {
instr := encode(s)
if s.labelSymbol != "" {
instr.symbolDefinition = s.labelSymbol
definedSymbols[s.labelSymbol].instr = instr
labeledSymbols[s.labelSymbol].instr = instr
}
insts = append(insts, instr)
instr.index = index
Expand All @@ -542,7 +540,7 @@ func encodeAllText(ss []*Stmt) []byte {

// Optimize instructions length
for len(variableInstrs) > 0 {
variableInstrs = resolveVariableLengthInstrs(variableInstrs)
variableInstrs = resolveVariableLengthInstrs(variableInstrs, labeledSymbols)
}

var unresolvedCallTargets []*callTarget
Expand Down Expand Up @@ -571,7 +569,7 @@ func encodeAllText(ss []*Stmt) []byte {
// no neeed to resolve. keep zeros.
} else {
if appearedSymbolDefs[call.trgtSymbol] {
tryToSetAddrToCallTarget(call, allText)
tryToSetAddrToCallTarget(call, allText, labeledSymbols)
} else {
//debugf("the target symbol '%s' has not appeared. Keep call target zero\n", call.trgtSymbol)
unresolvedCallTargets = append(unresolvedCallTargets, call)
Expand All @@ -581,14 +579,14 @@ func encodeAllText(ss []*Stmt) []byte {
}

for _, call := range unresolvedCallTargets {
tryToSetAddrToCallTarget(call, allText)
tryToSetAddrToCallTarget(call, allText, labeledSymbols)
}

return allText
}

func tryToSetAddrToCallTarget(call *callTarget, allText []byte) {
callee, ok := definedSymbols[call.trgtSymbol]
func tryToSetAddrToCallTarget(call *callTarget, allText []byte, labeledSymbols map[string]*symbolDefinition) {
callee, ok := labeledSymbols[call.trgtSymbol]
if ok {
diff := callee.instr.addr - call.caller.next.addr
placeToEmbed := call.caller.addr + call.offset
Expand All @@ -604,11 +602,11 @@ func tryToSetAddrToCallTarget(call *callTarget, allText []byte) {

}

func encodeAllData(ss []*Stmt) []byte {
func encodeAllData(ss []*Stmt, labeledSymbols map[string]*symbolDefinition) []byte {
var dataAddr uintptr
var allData []byte
for _, s := range ss {
buf := encodeData(s, dataAddr)
buf := encodeData(s, dataAddr, labeledSymbols)
dataAddr += uintptr(len(buf))
allData = append(allData, buf...)
}
Expand Down Expand Up @@ -643,13 +641,13 @@ func main() {
}

stmts, symbolsInLexicalOrder := ParseFiles(inFiles)
textStmts, dataStmts := analyzeStatements(stmts)
s_text.contents = encodeAllText(textStmts)
s_data.contents = encodeAllData(dataStmts)
textStmts, dataStmts, labeledSymbols := analyzeStatements(stmts)
s_text.contents = encodeAllText(textStmts, labeledSymbols)
s_data.contents = encodeAllData(dataStmts, labeledSymbols)

hasRelaText := len(relaTextUsers) > 0
hasRelaData := len(relaDataUsers) > 0
hasSymbols := len(definedSymbols) > 0
hasSymbols := len(labeledSymbols) > 0

sectionHeaders := buildSectionHeaders(hasRelaText, hasRelaData, hasSymbols)

Expand All @@ -668,18 +666,18 @@ func main() {

var symbolIndex map[string]int

if len(definedSymbols) > 0 {
dataSymbolUsed := isDataSymbolUsed(definedSymbols, relaTextUsers, relaDataUsers)
s_symtab.header.sh_info, s_symtab.contents, symbolIndex = buildSymbolTable(dataSymbolUsed, globalSymbols, symbolsInLexicalOrder)
if len(labeledSymbols) > 0 {
dataSymbolUsed := isDataSymbolUsed(labeledSymbols, relaTextUsers, relaDataUsers)
s_symtab.header.sh_info, s_symtab.contents, symbolIndex = buildSymbolTable(dataSymbolUsed, globalSymbols, symbolsInLexicalOrder, labeledSymbols)
}

//debugf("[main] building sections ...\n")
sectionNames := makeSectionNames(hasRelaText, hasRelaData, hasSymbols)
s_shstrtab.contents = makeShStrTab(sectionNames)
resolveShNames(s_shstrtab.contents, sectionHeaders[1:])

s_rela_text.contents = buildRelaTextBody(symbolIndex)
s_rela_data.contents = buildRelaDataBody(symbolIndex)
s_rela_text.contents = buildRelaTextBody(symbolIndex, labeledSymbols)
s_rela_data.contents = buildRelaDataBody(symbolIndex, labeledSymbols)

sectionInBodyOrder := sortSectionsForBody(hasRelaText, hasRelaData, hasSymbols)
assert(len(sectionInBodyOrder) == len(sectionHeaders)-1, "sections len unmatch")
Expand All @@ -688,16 +686,15 @@ func main() {
elfFile.writeTo(w)
}

func analyzeStatements(stmts []*Stmt) ([]*Stmt, []*Stmt) {

func analyzeStatements(stmts []*Stmt) ([]*Stmt, []*Stmt, map[string]*symbolDefinition) {
var labeledSymbols = make(map[string]*symbolDefinition)
var textStmts []*Stmt
var dataStmts []*Stmt

var currentSection = ".text"
for _, s := range stmts {

if s.labelSymbol != "" {
definedSymbols[s.labelSymbol] = &symbolDefinition{
labeledSymbols[s.labelSymbol] = &symbolDefinition{
name: s.labelSymbol,
section: currentSection,
}
Expand All @@ -722,15 +719,15 @@ func analyzeStatements(stmts []*Stmt) ([]*Stmt, []*Stmt) {
textStmts = append(textStmts, s)
}
}
return textStmts, dataStmts
return textStmts, dataStmts, labeledSymbols
}

func buildRelaTextBody(symbolIndex map[string]int) []byte {
func buildRelaTextBody(symbolIndex map[string]int, labeledSymbols map[string]*symbolDefinition) []byte {
var contents []byte

for _, ru := range relaTextUsers {
//debugf("checking relaTextUsers %s\n" , ru.uses)
sym, defined := definedSymbols[ru.uses]
sym, defined := labeledSymbols[ru.uses]
var addr int64
if defined {
// local functions do not need rela text
Expand Down Expand Up @@ -772,11 +769,11 @@ func buildRelaTextBody(symbolIndex map[string]int) []byte {
return contents
}

func buildRelaDataBody(symbolIndex map[string]int) []byte {
func buildRelaDataBody(symbolIndex map[string]int, labeledSymbols map[string]*symbolDefinition) []byte {
var contents []byte
for _, ru := range relaDataUsers {
//debugf("checking relaDataUsers %s\n", ru.uses)
sym, defined := definedSymbols[ru.uses]
sym, defined := labeledSymbols[ru.uses]
if !defined {
panic("label not found")
}
Expand Down

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