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Symbol names with more than two '.'s could be defined as constants

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Dot-only names could also trip an assertion in `make develop`
when used as labels
This commit is contained in:
Rangi42
2025-12-04 14:07:06 -05:00
committed by Rangi
parent ad3188f038
commit 752e2b3620
13 changed files with 78 additions and 7 deletions
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8
src/asm/lexer.cpp
View File

@@ -1295,7 +1295,7 @@ static Token readIdentifier(char firstChar, bool raw) {
}
// Label scopes `.` and `..` are the only nonlocal identifiers that start with a dot
if (identifier.find_first_not_of('.') == identifier.npos) {
if (sym_IsDotScope(identifier)) {
tokenType = T_(SYMBOL);
}
@@ -1939,11 +1939,12 @@ static Token yylex_NORMAL() {
// `token` is either a `SYMBOL` or a `LOCAL`, and both have a `std::string` value.
assume(std::holds_alternative<std::string>(token.value));
std::string const &identifier = std::get<std::string>(token.value);
// Raw symbols and local symbols cannot be string expansions
if (!raw && token.type == T_(SYMBOL) && lexerState->expandStrings) {
// Attempt string expansion
if (Symbol const *sym = sym_FindExactSymbol(std::get<std::string>(token.value));
if (Symbol const *sym = sym_FindExactSymbol(identifier);
sym && sym->type == SYM_EQUS) {
beginExpansion(sym->getEqus(), sym->name);
continue; // Restart, reading from the new buffer
@@ -1954,6 +1955,7 @@ static Token yylex_NORMAL() {
// - label definitions (which are followed by a ':' and use the token `LABEL`)
// - quiet macro invocations (which are followed by a '?' and use the token `QMACRO`)
// - regular macro invocations (which use the token `SYMBOL`)
// - label scopes "." and ".." (which use the token `SYMBOL` no matter what)
//
// If we had one `IDENTIFIER` token, the parser would need to perform "lookahead" to
// determine which rule applies. But since macros need to enter "raw" mode to parse
@@ -1964,7 +1966,7 @@ static Token yylex_NORMAL() {
// one to lex depending on the character *immediately* following the identifier.
// Thus "name:" is a label definition, and "name?" is a quiet macro invocation, but
// "name :" and "name ?" and just "name" are all regular macro invocations.
if (token.type == T_(SYMBOL)) {
if (token.type == T_(SYMBOL) && !sym_IsDotScope(identifier)) {
c = peek();
token.type = c == ':' ? T_(LABEL) : c == '?' ? T_(QMACRO) : T_(SYMBOL);
}

12
src/asm/symbol.cpp
View File

@@ -53,6 +53,12 @@ bool sym_IsPC(Symbol const *sym) {
return sym == PCSymbol;
}
bool sym_IsDotScope(std::string const &symName) {
// Label scopes `.` and `..` are the only nonlocal identifiers that start with a dot.
// Three or more dots are considered a nonsensical local label.
return symName == "." || symName == "..";
}
void sym_ForEach(void (*callback)(Symbol &)) {
for (auto &it : symbols) {
callback(it.second);
@@ -215,8 +221,8 @@ static void redefinedError(Symbol const &sym) {
static void assumeAlreadyExpanded(std::string const &symName) {
// Either the symbol name is `Global.local` or entirely '.'s (for scopes `.` and `..`),
// but cannot be unqualified `.local`
assume(!symName.starts_with('.') || symName.find_first_not_of('.') == symName.npos);
// but cannot be unqualified `.local` or more than two '.'s
assume(!symName.starts_with('.') || sym_IsDotScope(symName));
}
static Symbol &createSymbol(std::string const &symName) {
@@ -253,7 +259,7 @@ static bool isAutoScoped(std::string const &symName) {
}
// Label scopes `.` and `..` are the only nonlocal identifiers that start with a dot
if (dotPos == 0 && symName.find_first_not_of('.') == symName.npos) {
if (sym_IsDotScope(symName)) {
return false;
}