From 1ac3c0262f16076b289a61535d924cac38bd1bee Mon Sep 17 00:00:00 2001
From: Sylvie <35663410+Rangi42@users.noreply.github.com>
Date: Fri, 1 Mar 2024 13:11:45 -0500
Subject: [PATCH] Refactor structs to use methods instead of functions (#1322)

---
 include/asm/format.hpp  |  21 +++--
 include/asm/fstack.hpp  |   3 +-
 include/asm/macro.hpp   |  12 ++-
 include/asm/rpn.hpp     |  25 ++---
 include/asm/section.hpp |   5 +-
 include/asm/symbol.hpp  |  67 ++++---------
 include/link/main.hpp   |  22 ++---
 src/asm/format.cpp      | 203 +++++++++++++++++++---------------------
 src/asm/fstack.cpp      |  50 +++++-----
 src/asm/lexer.cpp       |  30 +++---
 src/asm/macro.cpp       |  46 +++------
 src/asm/output.cpp      |   8 +-
 src/asm/parser.y        |  55 ++++++-----
 src/asm/rpn.cpp         | 136 +++++++++++++--------------
 src/asm/section.cpp     |  54 +++++------
 src/asm/symbol.cpp      |  47 +++++-----
 src/link/main.cpp       |  22 ++---
 src/link/symbol.cpp     |   4 +-
 18 files changed, 364 insertions(+), 446 deletions(-)

diff --git a/include/asm/format.hpp b/include/asm/format.hpp
index ee57437c..85521eb8 100644
--- a/include/asm/format.hpp
+++ b/include/asm/format.hpp
@@ -15,7 +15,7 @@ enum FormatState {
 	FORMAT_INVALID, // got unexpected character
 };
 
-struct FormatSpec {
+class FormatSpec {
 	enum FormatState state;
 	int sign;
 	bool prefix;
@@ -26,15 +26,16 @@ struct FormatSpec {
 	size_t fracWidth;
 	int type;
 	bool valid;
+
+public:
+	bool isEmpty() const { return !state; }
+	bool isValid() const { return valid || state == FORMAT_DONE; }
+	bool isFinished() const { return state >= FORMAT_DONE;}
+
+	void useCharacter(int c);
+	void finishCharacters();
+	void printString(char *buf, size_t bufLen, char const *value);
+	void printNumber(char *buf, size_t bufLen, uint32_t value);
 };
 
-FormatSpec fmt_NewSpec();
-bool fmt_IsEmpty(FormatSpec const *fmt);
-bool fmt_IsValid(FormatSpec const *fmt);
-bool fmt_IsFinished(FormatSpec const *fmt);
-void fmt_UseCharacter(FormatSpec *fmt, int c);
-void fmt_FinishCharacters(FormatSpec *fmt);
-void fmt_PrintString(char *buf, size_t bufLen, FormatSpec const *fmt, char const *value);
-void fmt_PrintNumber(char *buf, size_t bufLen, FormatSpec const *fmt, uint32_t value);
-
 #endif // RGBDS_FORMAT_SPEC_H
diff --git a/include/asm/fstack.hpp b/include/asm/fstack.hpp
index c0e66587..7fa6a4f4 100644
--- a/include/asm/fstack.hpp
+++ b/include/asm/fstack.hpp
@@ -36,6 +36,8 @@ struct FileStackNode {
 	// File name for files, file::macro name for macros
 	std::string &name();
 	std::string const &name() const;
+
+	void dump(uint32_t curLineNo) const;
 };
 
 #define DEFAULT_MAX_DEPTH 64
@@ -43,7 +45,6 @@ extern size_t maxRecursionDepth;
 
 struct MacroArgs;
 
-void fstk_Dump(FileStackNode const *node, uint32_t lineNo);
 void fstk_DumpCurrent();
 FileStackNode *fstk_GetFileStack();
 // The lifetime of the returned chars is until reaching the end of that file
diff --git a/include/asm/macro.hpp b/include/asm/macro.hpp
index 7f330738..67b74fb6 100644
--- a/include/asm/macro.hpp
+++ b/include/asm/macro.hpp
@@ -5,18 +5,22 @@
 
 #include <stdint.h>
 #include <stdlib.h>
+#include <vector>
 
 #include "asm/warning.hpp"
 
 #include "helpers.hpp"
 
-struct MacroArgs;
+struct MacroArgs {
+	unsigned int shift;
+	std::vector<char *> args;
+
+	void append(char *s);
+	void clear();
+};
 
 MacroArgs *macro_GetCurrentArgs();
-MacroArgs *macro_NewArgs();
-void macro_AppendArg(MacroArgs *args, char *s);
 void macro_UseNewArgs(MacroArgs *args);
-void macro_FreeArgs(MacroArgs *args);
 char const *macro_GetArg(uint32_t i);
 char const *macro_GetAllArgs();
 
diff --git a/include/asm/rpn.hpp b/include/asm/rpn.hpp
index 0f1b24e5..225d9a75 100644
--- a/include/asm/rpn.hpp
+++ b/include/asm/rpn.hpp
@@ -13,29 +13,19 @@ struct Symbol;
 struct Expression {
 	int32_t val; // If the expression's value is known, it's here
 	std::string *reason; // Why the expression is not known, if it isn't
-	bool isKnown; // Whether the expression's value is known
-	bool isSymbol; // Whether the expression represents a symbol
+	bool isKnown; // Whether the expression's value is known at assembly time
+	bool isSymbol; // Whether the expression represents a symbol suitable for const diffing
 	std::vector<uint8_t> *rpn; // Bytes serializing the RPN expression
 	uint32_t rpnPatchSize; // Size the expression will take in the object file
+
+	int32_t getConstVal() const;
+	Symbol const *symbolOf() const;
+	bool isDiffConstant(Symbol const *symName) const;
 };
 
-// Determines if an expression is known at assembly time
-static inline bool rpn_isKnown(Expression const *expr)
-{
-	return expr->isKnown;
-}
-
-// Determines if an expression is a symbol suitable for const diffing
-static inline bool rpn_isSymbol(const Expression *expr)
-{
-	return expr->isSymbol;
-}
-
 void rpn_Symbol(Expression *expr, char const *symName);
 void rpn_Number(Expression *expr, uint32_t i);
 void rpn_LOGNOT(Expression *expr, const Expression *src);
-Symbol const *rpn_SymbolOf(Expression const *expr);
-bool rpn_IsDiffConstant(Expression const *src, Symbol const *symName);
 void rpn_BinaryOp(enum RPNCommand op, Expression *expr, const Expression *src1, const Expression *src2);
 void rpn_HIGH(Expression *expr, const Expression *src);
 void rpn_LOW(Expression *expr, const Expression *src);
@@ -49,10 +39,11 @@ void rpn_SizeOfSection(Expression *expr, char const *sectionName);
 void rpn_StartOfSection(Expression *expr, char const *sectionName);
 void rpn_SizeOfSectionType(Expression *expr, enum SectionType type);
 void rpn_StartOfSectionType(Expression *expr, enum SectionType type);
+
 void rpn_Free(Expression *expr);
+
 void rpn_CheckHRAM(Expression *expr, const Expression *src);
 void rpn_CheckRST(Expression *expr, const Expression *src);
 void rpn_CheckNBit(Expression const *expr, uint8_t n);
-int32_t rpn_GetConstVal(Expression const *expr);
 
 #endif // RGBDS_ASM_RPN_H
diff --git a/include/asm/section.hpp b/include/asm/section.hpp
index 4ed6c9c6..4862cac1 100644
--- a/include/asm/section.hpp
+++ b/include/asm/section.hpp
@@ -8,7 +8,6 @@
 #include <vector>
 
 #include "linkdefs.hpp"
-#include "platform.hpp" // NONNULL
 
 extern uint8_t fillByte;
 
@@ -39,6 +38,8 @@ struct Section {
 	uint16_t alignOfs;
 	std::deque<Patch> patches;
 	std::vector<uint8_t> data;
+
+	bool isSizeKnown() const;
 };
 
 struct SectionSpec {
@@ -85,6 +86,4 @@ void sect_EndSection();
 void sect_PushSection();
 void sect_PopSection();
 
-bool sect_IsSizeKnown(Section const NONNULL(name));
-
 #endif // RGBDS_SECTION_H
diff --git a/include/asm/symbol.hpp b/include/asm/symbol.hpp
index 63d81d01..dc1c353e 100644
--- a/include/asm/symbol.hpp
+++ b/include/asm/symbol.hpp
@@ -29,6 +29,9 @@ struct strValue {
 	char *value;
 };
 
+struct Symbol; // For the `sym_IsPC` forward declaration
+bool sym_IsPC(Symbol const *sym); // For the inline `getSection` method
+
 struct Symbol {
 	char name[MAXSYMLEN + 1];
 	enum SymbolType type;
@@ -40,7 +43,7 @@ struct Symbol {
 
 	bool hasCallback;
 	union {
-		// If sym_IsNumeric
+		// If isNumeric()
 		int32_t value;
 		int32_t (*numCallback)(); // If hasCallback
 		// For SYM_MACRO
@@ -51,61 +54,28 @@ struct Symbol {
 	};
 
 	uint32_t ID; // ID of the symbol in the object file (-1 if none)
-};
 
-bool sym_IsPC(Symbol const *sym);
+	bool isDefined() const { return type != SYM_REF; }
+	bool isNumeric() const { return type == SYM_LABEL || type == SYM_EQU || type == SYM_VAR; }
+	bool isLabel() const { return type == SYM_LABEL || type == SYM_REF; }
 
-static inline bool sym_IsDefined(Symbol const *sym)
-{
-	return sym->type != SYM_REF;
-}
-
-static inline Section *sym_GetSection(Symbol const *sym)
-{
-	return sym_IsPC(sym) ? sect_GetSymbolSection() : sym->section;
-}
-
-static inline bool sym_IsConstant(Symbol const *sym)
-{
-	if (sym->type == SYM_LABEL) {
-		Section const *sect = sym_GetSection(sym);
-
-		return sect && sect->org != (uint32_t)-1;
+	bool isConstant() const {
+		if (type == SYM_LABEL) {
+			Section const *sect = getSection();
+			return sect && sect->org != (uint32_t)-1;
+		}
+		return type == SYM_EQU || type == SYM_VAR;
 	}
-	return sym->type == SYM_EQU || sym->type == SYM_VAR;
-}
 
-static inline bool sym_IsNumeric(Symbol const *sym)
-{
-	return sym->type == SYM_LABEL || sym->type == SYM_EQU || sym->type == SYM_VAR;
-}
+	Section *getSection() const { return sym_IsPC(this) ? sect_GetSymbolSection() : section; }
 
-static inline bool sym_IsLabel(Symbol const *sym)
-{
-	return sym->type == SYM_LABEL || sym->type == SYM_REF;
-}
-
-static inline bool sym_IsLocal(Symbol const *sym)
-{
-	return sym_IsLabel(sym) && strchr(sym->name, '.');
-}
-
-static inline bool sym_IsExported(Symbol const *sym)
-{
-	return sym->isExported;
-}
-
-// Get a string equate's value
-static inline char const *sym_GetStringValue(Symbol const *sym)
-{
-	if (sym->hasCallback)
-		return sym->strCallback();
-	return sym->equs.value;
-}
+	int32_t getValue() const;
+	uint32_t getConstantValue() const;
+	char const *getStringValue() const { return hasCallback ? strCallback() : equs.value; }
+};
 
 void sym_ForEach(void (*func)(Symbol *));
 
-int32_t sym_GetValue(Symbol const *sym);
 void sym_SetExportAll(bool set);
 Symbol *sym_AddLocalLabel(char const *symName);
 Symbol *sym_AddLabel(char const *symName);
@@ -116,7 +86,6 @@ Symbol *sym_AddEqu(char const *symName, int32_t value);
 Symbol *sym_RedefEqu(char const *symName, int32_t value);
 Symbol *sym_AddVar(char const *symName, int32_t value);
 uint32_t sym_GetPCValue();
-uint32_t sym_GetConstantSymValue(Symbol const *sym);
 uint32_t sym_GetConstantValue(char const *symName);
 // Find a symbol by exact name, bypassing expansion checks
 Symbol *sym_FindExactSymbol(char const *symName);
diff --git a/include/link/main.hpp b/include/link/main.hpp
index 65c897ff..e48567ab 100644
--- a/include/link/main.hpp
+++ b/include/link/main.hpp
@@ -30,6 +30,12 @@ extern bool beVerbose;
 extern bool isWRAM0Mode;
 extern bool disablePadding;
 
+// Helper macro for printing verbose-mode messages
+#define verbosePrint(...) do { \
+	if (beVerbose) \
+		fprintf(stderr, __VA_ARGS__); \
+} while (0)
+
 struct FileStackNode {
 	FileStackNode *parent;
 	// Line at which the parent context was exited; meaningless for the root level
@@ -48,24 +54,12 @@ struct FileStackNode {
 	// File name for files, file::macro name for macros
 	std::string &name();
 	std::string const &name() const;
+
+	std::string const *dumpFileStack() const;
 };
 
-// Helper macro for printing verbose-mode messages
-#define verbosePrint(...)   do { \
-					if (beVerbose) \
-						fprintf(stderr, __VA_ARGS__); \
-				} while (0)
-
-/*
- * Dump a file stack to stderr
- * @param node The leaf node to dump the context of
- */
-std::string const *dumpFileStack(FileStackNode const *node);
-
 void warning(FileStackNode const *where, uint32_t lineNo, char const *fmt, ...) format_(printf, 3, 4);
-
 void error(FileStackNode const *where, uint32_t lineNo, char const *fmt, ...) format_(printf, 3, 4);
-
 [[noreturn]] void fatal(FileStackNode const *where, uint32_t lineNo, char const *fmt, ...) format_(printf, 3, 4);
 
 #endif // RGBDS_LINK_MAIN_H
diff --git a/src/asm/format.cpp b/src/asm/format.cpp
index 258c15b2..c60e27af 100644
--- a/src/asm/format.cpp
+++ b/src/asm/format.cpp
@@ -12,63 +12,41 @@
 #include "asm/format.hpp"
 #include "asm/warning.hpp"
 
-FormatSpec fmt_NewSpec()
+void FormatSpec::useCharacter(int c)
 {
-	FormatSpec fmt = {};
-
-	return fmt;
-}
-
-bool fmt_IsEmpty(FormatSpec const *fmt)
-{
-	return !fmt->state;
-}
-
-bool fmt_IsValid(FormatSpec const *fmt)
-{
-	return fmt->valid || fmt->state == FORMAT_DONE;
-}
-
-bool fmt_IsFinished(FormatSpec const *fmt)
-{
-	return fmt->state >= FORMAT_DONE;
-}
-
-void fmt_UseCharacter(FormatSpec *fmt, int c)
-{
-	if (fmt->state == FORMAT_INVALID)
+	if (state == FORMAT_INVALID)
 		return;
 
 	switch (c) {
 	// sign
 	case ' ':
 	case '+':
-		if (fmt->state > FORMAT_SIGN)
+		if (state > FORMAT_SIGN)
 			goto invalid;
-		fmt->state = FORMAT_PREFIX;
-		fmt->sign = c;
+		state = FORMAT_PREFIX;
+		sign = c;
 		break;
 
 	// prefix
 	case '#':
-		if (fmt->state > FORMAT_PREFIX)
+		if (state > FORMAT_PREFIX)
 			goto invalid;
-		fmt->state = FORMAT_ALIGN;
-		fmt->prefix = true;
+		state = FORMAT_ALIGN;
+		prefix = true;
 		break;
 
 	// align
 	case '-':
-		if (fmt->state > FORMAT_ALIGN)
+		if (state > FORMAT_ALIGN)
 			goto invalid;
-		fmt->state = FORMAT_WIDTH;
-		fmt->alignLeft = true;
+		state = FORMAT_WIDTH;
+		alignLeft = true;
 		break;
 
 	// pad and width
 	case '0':
-		if (fmt->state < FORMAT_WIDTH)
-			fmt->padZero = true;
+		if (state < FORMAT_WIDTH)
+			padZero = true;
 		// fallthrough
 	case '1':
 	case '2':
@@ -79,23 +57,23 @@ void fmt_UseCharacter(FormatSpec *fmt, int c)
 	case '7':
 	case '8':
 	case '9':
-		if (fmt->state < FORMAT_WIDTH) {
-			fmt->state = FORMAT_WIDTH;
-			fmt->width = c - '0';
-		} else if (fmt->state == FORMAT_WIDTH) {
-			fmt->width = fmt->width * 10 + (c - '0');
-		} else if (fmt->state == FORMAT_FRAC) {
-			fmt->fracWidth = fmt->fracWidth * 10 + (c - '0');
+		if (state < FORMAT_WIDTH) {
+			state = FORMAT_WIDTH;
+			width = c - '0';
+		} else if (state == FORMAT_WIDTH) {
+			width = width * 10 + (c - '0');
+		} else if (state == FORMAT_FRAC) {
+			fracWidth = fracWidth * 10 + (c - '0');
 		} else {
 			goto invalid;
 		}
 		break;
 
 	case '.':
-		if (fmt->state > FORMAT_WIDTH)
+		if (state > FORMAT_WIDTH)
 			goto invalid;
-		fmt->state = FORMAT_FRAC;
-		fmt->hasFrac = true;
+		state = FORMAT_FRAC;
+		hasFrac = true;
 		break;
 
 	// type
@@ -107,41 +85,46 @@ void fmt_UseCharacter(FormatSpec *fmt, int c)
 	case 'o':
 	case 'f':
 	case 's':
-		if (fmt->state >= FORMAT_DONE)
+		if (state >= FORMAT_DONE)
 			goto invalid;
-		fmt->state = FORMAT_DONE;
-		fmt->valid = true;
-		fmt->type = c;
+		state = FORMAT_DONE;
+		valid = true;
+		type = c;
 		break;
 
 	default:
 invalid:
-		fmt->state = FORMAT_INVALID;
-		fmt->valid = false;
+		state = FORMAT_INVALID;
+		valid = false;
 	}
 }
 
-void fmt_FinishCharacters(FormatSpec *fmt)
+void FormatSpec::finishCharacters()
 {
-	if (!fmt_IsValid(fmt))
-		fmt->state = FORMAT_INVALID;
+	if (!isValid())
+		state = FORMAT_INVALID;
 }
 
-void fmt_PrintString(char *buf, size_t bufLen, FormatSpec const *fmt, char const *value)
+void FormatSpec::printString(char *buf, size_t bufLen, char const *value)
 {
-	if (fmt->sign)
-		error("Formatting string with sign flag '%c'\n", fmt->sign);
-	if (fmt->prefix)
+	if (isEmpty()) {
+		// No format was specified
+		type = 's';
+	}
+
+	if (sign)
+		error("Formatting string with sign flag '%c'\n", sign);
+	if (prefix)
 		error("Formatting string with prefix flag '#'\n");
-	if (fmt->padZero)
+	if (padZero)
 		error("Formatting string with padding flag '0'\n");
-	if (fmt->hasFrac)
+	if (hasFrac)
 		error("Formatting string with fractional width\n");
-	if (fmt->type != 's')
-		error("Formatting string as type '%c'\n", fmt->type);
+	if (type != 's')
+		error("Formatting string as type '%c'\n", type);
 
 	size_t len = strlen(value);
-	size_t totalLen = fmt->width > len ? fmt->width : len;
+	size_t totalLen = width > len ? width : len;
 
 	if (totalLen > bufLen - 1) { // bufLen includes terminator
 		error("Formatted string value too long\n");
@@ -153,7 +136,7 @@ void fmt_PrintString(char *buf, size_t bufLen, FormatSpec const *fmt, char const
 
 	size_t padLen = totalLen - len;
 
-	if (fmt->alignLeft) {
+	if (alignLeft) {
 		memcpy(buf, value, len);
 		for (size_t i = len; i < totalLen; i++)
 			buf[i] = ' ';
@@ -166,37 +149,42 @@ void fmt_PrintString(char *buf, size_t bufLen, FormatSpec const *fmt, char const
 	buf[totalLen] = '\0';
 }
 
-void fmt_PrintNumber(char *buf, size_t bufLen, FormatSpec const *fmt, uint32_t value)
+void FormatSpec::printNumber(char *buf, size_t bufLen, uint32_t value)
 {
-	if (fmt->type != 'X' && fmt->type != 'x' && fmt->type != 'b' && fmt->type != 'o'
-	    && fmt->prefix)
-		error("Formatting type '%c' with prefix flag '#'\n", fmt->type);
-	if (fmt->type != 'f' && fmt->hasFrac)
-		error("Formatting type '%c' with fractional width\n", fmt->type);
-	if (fmt->type == 's')
+	if (isEmpty()) {
+		// No format was specified; default to uppercase $hex
+		type = 'X';
+		prefix = true;
+	}
+
+	if (type != 'X' && type != 'x' && type != 'b' && type != 'o' && prefix)
+		error("Formatting type '%c' with prefix flag '#'\n", type);
+	if (type != 'f' && hasFrac)
+		error("Formatting type '%c' with fractional width\n", type);
+	if (type == 's')
 		error("Formatting number as type 's'\n");
 
-	char sign = fmt->sign; // 0 or ' ' or '+'
+	char signChar = sign; // 0 or ' ' or '+'
 
-	if (fmt->type == 'd' || fmt->type == 'f') {
+	if (type == 'd' || type == 'f') {
 		int32_t v = value;
 
 		if (v < 0 && v != INT32_MIN) {
-			sign = '-';
+			signChar = '-';
 			value = -v;
 		}
 	}
 
-	char prefix = !fmt->prefix ? 0
-		: fmt->type == 'X' ? '$'
-		: fmt->type == 'x' ? '$'
-		: fmt->type == 'b' ? '%'
-		: fmt->type == 'o' ? '&'
+	char prefixChar = !prefix ? 0
+		: type == 'X' ? '$'
+		: type == 'x' ? '$'
+		: type == 'b' ? '%'
+		: type == 'o' ? '&'
 		: 0;
 
 	char valueBuf[262]; // Max 5 digits + decimal + 255 fraction digits + terminator
 
-	if (fmt->type == 'b') {
+	if (type == 'b') {
 		// Special case for binary
 		char *ptr = valueBuf;
 
@@ -216,34 +204,33 @@ void fmt_PrintNumber(char *buf, size_t bufLen, FormatSpec const *fmt, uint32_t v
 			valueBuf[i] = valueBuf[j];
 			valueBuf[j] = c;
 		}
-	} else if (fmt->type == 'f') {
+	} else if (type == 'f') {
 		// Special case for fixed-point
 
 		// Default fractional width (C++'s is 6 for "%f"; here 5 is enough for Q16.16)
-		size_t fracWidth = fmt->hasFrac ? fmt->fracWidth : 5;
+		size_t cappedFracWidth = hasFrac ? fracWidth : 5;
 
-		if (fracWidth > 255) {
-			error("Fractional width %zu too long, limiting to 255\n",
-			      fracWidth);
-			fracWidth = 255;
+		if (cappedFracWidth > 255) {
+			error("Fractional width %zu too long, limiting to 255\n", cappedFracWidth);
+			cappedFracWidth = 255;
 		}
 
-		snprintf(valueBuf, sizeof(valueBuf), "%.*f", (int)fracWidth,
+		snprintf(valueBuf, sizeof(valueBuf), "%.*f", (int)cappedFracWidth,
 			 value / fix_PrecisionFactor());
 	} else {
-		char const *spec = fmt->type == 'd' ? "%" PRId32
-				 : fmt->type == 'u' ? "%" PRIu32
-				 : fmt->type == 'X' ? "%" PRIX32
-				 : fmt->type == 'x' ? "%" PRIx32
-				 : fmt->type == 'o' ? "%" PRIo32
+		char const *spec = type == 'd' ? "%" PRId32
+				 : type == 'u' ? "%" PRIu32
+				 : type == 'X' ? "%" PRIX32
+				 : type == 'x' ? "%" PRIx32
+				 : type == 'o' ? "%" PRIo32
 				 : "%" PRId32;
 
 		snprintf(valueBuf, sizeof(valueBuf), spec, value);
 	}
 
 	size_t len = strlen(valueBuf);
-	size_t numLen = (sign != 0) + (prefix != 0) + len;
-	size_t totalLen = fmt->width > numLen ? fmt->width : numLen;
+	size_t numLen = (signChar != 0) + (prefixChar != 0) + len;
+	size_t totalLen = width > numLen ? width : numLen;
 
 	if (totalLen > bufLen - 1) { // bufLen includes terminator
 		error("Formatted numeric value too long\n");
@@ -258,31 +245,31 @@ void fmt_PrintNumber(char *buf, size_t bufLen, FormatSpec const *fmt, uint32_t v
 	size_t padLen = totalLen - numLen;
 	size_t pos = 0;
 
-	if (fmt->alignLeft) {
-		if (sign)
-			buf[pos++] = sign;
-		if (prefix)
-			buf[pos++] = prefix;
+	if (alignLeft) {
+		if (signChar)
+			buf[pos++] = signChar;
+		if (prefixChar)
+			buf[pos++] = prefixChar;
 		memcpy(buf + pos, valueBuf, len);
 		for (size_t i = pos + len; i < totalLen; i++)
 			buf[i] = ' ';
 	} else {
-		if (fmt->padZero) {
+		if (padZero) {
 			// sign, then prefix, then zero padding
-			if (sign)
-				buf[pos++] = sign;
-			if (prefix)
-				buf[pos++] = prefix;
+			if (signChar)
+				buf[pos++] = signChar;
+			if (prefixChar)
+				buf[pos++] = prefixChar;
 			for (size_t i = 0; i < padLen; i++)
 				buf[pos++] = '0';
 		} else {
 			// space padding, then sign, then prefix
 			for (size_t i = 0; i < padLen; i++)
 				buf[pos++] = ' ';
-			if (sign)
-				buf[pos++] = sign;
-			if (prefix)
-				buf[pos++] = prefix;
+			if (signChar)
+				buf[pos++] = signChar;
+			if (prefixChar)
+				buf[pos++] = prefixChar;
 		}
 		memcpy(buf + pos, valueBuf, len);
 	}
diff --git a/src/asm/fstack.cpp b/src/asm/fstack.cpp
index e395543e..fab459c9 100644
--- a/src/asm/fstack.cpp
+++ b/src/asm/fstack.cpp
@@ -42,6 +42,26 @@ static std::vector<std::string> includePaths = { "" };
 
 static const char *preIncludeName;
 
+std::vector<uint32_t> &FileStackNode::iters() {
+	assert(std::holds_alternative<std::vector<uint32_t>>(data));
+	return std::get<std::vector<uint32_t>>(data);
+}
+
+std::vector<uint32_t> const &FileStackNode::iters() const {
+	assert(std::holds_alternative<std::vector<uint32_t>>(data));
+	return std::get<std::vector<uint32_t>>(data);
+}
+
+std::string &FileStackNode::name() {
+	assert(std::holds_alternative<std::string>(data));
+	return std::get<std::string>(data);
+}
+
+std::string const &FileStackNode::name() const {
+	assert(std::holds_alternative<std::string>(data));
+	return std::get<std::string>(data);
+}
+
 static const char *dumpNodeAndParents(FileStackNode const *node)
 {
 	char const *name;
@@ -66,30 +86,10 @@ static const char *dumpNodeAndParents(FileStackNode const *node)
 	return name;
 }
 
-std::vector<uint32_t> &FileStackNode::iters() {
-	assert(std::holds_alternative<std::vector<uint32_t>>(data));
-	return std::get<std::vector<uint32_t>>(data);
-}
-
-std::vector<uint32_t> const &FileStackNode::iters() const {
-	assert(std::holds_alternative<std::vector<uint32_t>>(data));
-	return std::get<std::vector<uint32_t>>(data);
-}
-
-std::string &FileStackNode::name() {
-	assert(std::holds_alternative<std::string>(data));
-	return std::get<std::string>(data);
-}
-
-std::string const &FileStackNode::name() const {
-	assert(std::holds_alternative<std::string>(data));
-	return std::get<std::string>(data);
-}
-
-void fstk_Dump(FileStackNode const *node, uint32_t lineNo)
+void FileStackNode::dump(uint32_t curLineNo) const
 {
-	dumpNodeAndParents(node);
-	fprintf(stderr, "(%" PRIu32 ")", lineNo);
+	dumpNodeAndParents(this);
+	fprintf(stderr, "(%" PRIu32 ")", curLineNo);
 }
 
 void fstk_DumpCurrent()
@@ -98,7 +98,7 @@ void fstk_DumpCurrent()
 		fputs("at top level", stderr);
 		return;
 	}
-	fstk_Dump(contextStack.top().fileInfo, lexer_GetLineNo());
+	contextStack.top().fileInfo->dump(lexer_GetLineNo());
 }
 
 FileStackNode *fstk_GetFileStack()
@@ -240,7 +240,7 @@ bool yywrap()
 	lexer_CleanupState(oldContext.lexerState);
 	// Restore args if a macro (not REPT) saved them
 	if (oldContext.fileInfo->type == NODE_MACRO) {
-		macro_FreeArgs(macro_GetCurrentArgs());
+		macro_GetCurrentArgs()->clear();
 		macro_UseNewArgs(contextStack.top().macroArgs);
 	}
 	// Free the file stack node
diff --git a/src/asm/lexer.cpp b/src/asm/lexer.cpp
index bb1be518..4496aeaf 100644
--- a/src/asm/lexer.cpp
+++ b/src/asm/lexer.cpp
@@ -579,12 +579,12 @@ static uint32_t readBracketedMacroArgNum()
 			error("Bracketed symbol \"%s\" does not exist\n", symName);
 			num = 0;
 			symbolError = true;
-		} else if (!sym_IsNumeric(sym)) {
+		} else if (!sym->isNumeric()) {
 			error("Bracketed symbol \"%s\" is not numeric\n", symName);
 			num = 0;
 			symbolError = true;
 		} else {
-			num = sym_GetConstantSymValue(sym);
+			num = sym->getConstantValue();
 		}
 	} else {
 		empty = true;
@@ -1184,7 +1184,7 @@ static char const *readInterpolation(size_t depth)
 
 	char symName[MAXSYMLEN + 1];
 	size_t i = 0;
-	FormatSpec fmt = fmt_NewSpec();
+	FormatSpec fmt{};
 	bool disableInterpolation = lexerState->disableInterpolation;
 
 	// In a context where `lexerState->disableInterpolation` is true, `peek` will expand
@@ -1208,7 +1208,7 @@ static char const *readInterpolation(size_t depth)
 		} else if (c == '}') {
 			shiftChar();
 			break;
-		} else if (c == ':' && !fmt_IsFinished(&fmt)) { // Format spec, only once
+		} else if (c == ':' && !fmt.isFinished()) { // Format spec, only once
 			shiftChar();
 			if (i == sizeof(symName)) {
 				warning(WARNING_LONG_STR, "Format spec too long, got truncated\n");
@@ -1216,9 +1216,9 @@ static char const *readInterpolation(size_t depth)
 			}
 			symName[i] = '\0';
 			for (size_t j = 0; j < i; j++)
-				fmt_UseCharacter(&fmt, symName[j]);
-			fmt_FinishCharacters(&fmt);
-			if (!fmt_IsValid(&fmt))
+				fmt.useCharacter(symName[j]);
+			fmt.finishCharacters();
+			if (!fmt.isValid())
 				error("Invalid format spec '%s'\n", symName);
 			i = 0; // Now that format has been set, restart at beginning of string
 		} else {
@@ -1244,18 +1244,10 @@ static char const *readInterpolation(size_t depth)
 	if (!sym) {
 		error("Interpolated symbol \"%s\" does not exist\n", symName);
 	} else if (sym->type == SYM_EQUS) {
-		if (fmt_IsEmpty(&fmt))
-			// No format was specified
-			fmt.type = 's';
-		fmt_PrintString(buf, sizeof(buf), &fmt, sym_GetStringValue(sym));
+		fmt.printString(buf, sizeof(buf), sym->getStringValue());
 		return buf;
-	} else if (sym_IsNumeric(sym)) {
-		if (fmt_IsEmpty(&fmt)) {
-			// No format was specified; default to uppercase $hex
-			fmt.type = 'X';
-			fmt.prefix = true;
-		}
-		fmt_PrintNumber(buf, sizeof(buf), &fmt, sym_GetConstantSymValue(sym));
+	} else if (sym->isNumeric()) {
+		fmt.printNumber(buf, sizeof(buf), sym->getConstantValue());
 		return buf;
 	} else {
 		error("Only numerical and string symbols can be interpolated\n");
@@ -1884,7 +1876,7 @@ static int yylex_NORMAL()
 					Symbol const *sym = sym_FindExactSymbol(yylval.symName);
 
 					if (sym && sym->type == SYM_EQUS) {
-						char const *s = sym_GetStringValue(sym);
+						char const *s = sym->getStringValue();
 
 						assert(s);
 						if (s[0])
diff --git a/src/asm/macro.cpp b/src/asm/macro.cpp
index 9f7f7f38..4b0aa867 100644
--- a/src/asm/macro.cpp
+++ b/src/asm/macro.cpp
@@ -13,11 +13,6 @@
 
 #define MAXMACROARGS 99999
 
-struct MacroArgs {
-	unsigned int shift;
-	std::vector<char *> args;
-};
-
 static MacroArgs *macroArgs = nullptr;
 static uint32_t uniqueID = 0;
 static uint32_t maxUniqueID = 0;
@@ -27,42 +22,31 @@ static uint32_t maxUniqueID = 0;
 static char uniqueIDBuf[] = "_u4294967295"; // UINT32_MAX
 static char *uniqueIDPtr = nullptr;
 
+void MacroArgs::append(char *s)
+{
+	if (s[0] == '\0')
+		warning(WARNING_EMPTY_MACRO_ARG, "Empty macro argument\n");
+	if (args.size() == MAXMACROARGS)
+		error("A maximum of " EXPAND_AND_STR(MAXMACROARGS) " arguments is allowed\n");
+	args.push_back(s);
+}
+
+void MacroArgs::clear()
+{
+	for (char *arg : args)
+		free(arg);
+}
+
 MacroArgs *macro_GetCurrentArgs()
 {
 	return macroArgs;
 }
 
-MacroArgs *macro_NewArgs()
-{
-	MacroArgs *args = new(std::nothrow) MacroArgs();
-
-	if (!args)
-		fatalerror("Unable to register macro arguments: %s\n", strerror(errno));
-
-	args->shift = 0;
-	return args;
-}
-
-void macro_AppendArg(MacroArgs *args, char *s)
-{
-	if (s[0] == '\0')
-		warning(WARNING_EMPTY_MACRO_ARG, "Empty macro argument\n");
-	if (args->args.size() == MAXMACROARGS)
-		error("A maximum of " EXPAND_AND_STR(MAXMACROARGS) " arguments is allowed\n");
-	args->args.push_back(s);
-}
-
 void macro_UseNewArgs(MacroArgs *args)
 {
 	macroArgs = args;
 }
 
-void macro_FreeArgs(MacroArgs *args)
-{
-	for (char *arg : args->args)
-		free(arg);
-}
-
 char const *macro_GetArg(uint32_t i)
 {
 	if (!macroArgs)
diff --git a/src/asm/output.cpp b/src/asm/output.cpp
index d721e8e4..d5df428f 100644
--- a/src/asm/output.cpp
+++ b/src/asm/output.cpp
@@ -142,7 +142,7 @@ static void writesection(Section const &sect, FILE *f)
 static void writesymbol(Symbol const *sym, FILE *f)
 {
 	putstring(sym->name, f);
-	if (!sym_IsDefined(sym)) {
+	if (!sym->isDefined()) {
 		putc(SYMTYPE_IMPORT, f);
 	} else {
 		assert(sym->src->ID != (uint32_t)-1);
@@ -150,7 +150,7 @@ static void writesymbol(Symbol const *sym, FILE *f)
 		putc(sym->isExported ? SYMTYPE_EXPORT : SYMTYPE_LOCAL, f);
 		putlong(sym->src->ID, f);
 		putlong(sym->fileLine, f);
-		putlong(getSectIDIfAny(sym_GetSection(sym)), f);
+		putlong(getSectIDIfAny(sym->getSection()), f);
 		putlong(sym->value, f);
 	}
 }
@@ -203,7 +203,7 @@ static void writerpn(std::vector<uint8_t> &rpnexpr, const std::vector<uint8_t> &
 
 			// The symbol name is always written expanded
 			sym = sym_FindExactSymbol(symName);
-			if (sym_IsConstant(sym)) {
+			if (sym->isConstant()) {
 				writebyte(RPN_CONST);
 				value = sym_GetConstantValue(symName);
 			} else {
@@ -280,7 +280,7 @@ static void initpatch(Patch &patch, uint32_t type, Expression const *expr, uint3
 	patch.pcSection = sect_GetSymbolSection();
 	patch.pcOffset = sect_GetSymbolOffset();
 
-	if (rpn_isKnown(expr)) {
+	if (expr->isKnown) {
 		// If the RPN expr's value is known, output a constant directly
 		patch.rpn.resize(5);
 		patch.rpn[0] = RPN_CONST;
diff --git a/src/asm/parser.y b/src/asm/parser.y
index b86cefaf..2c2f8771 100644
--- a/src/asm/parser.y
+++ b/src/asm/parser.y
@@ -71,7 +71,7 @@
 			   char const *rep);
 	static void initStrFmtArgList(StrFmtArgList *args);
 	static void freeStrFmtArgList(StrFmtArgList *args);
-	static void strfmt(char *dest, size_t destLen, char const *fmt,
+	static void strfmt(char *dest, size_t destLen, char const *spec,
 			   std::vector<std::variant<uint32_t, char *>> &args);
 	static void compoundAssignment(const char *symName, enum RPNCommand op, int32_t constValue);
 	static void initDsArgList(std::vector<Expression> *&args);
@@ -503,10 +503,14 @@ macro		: T_ID {
 ;
 
 macroargs	: %empty {
-			$$ = macro_NewArgs();
+			$$ = new(std::nothrow) MacroArgs();
+			if (!$$)
+				fatalerror("Failed to allocate memory for macro arguments: %s\n",
+					   strerror(errno));
+			$$->shift = 0;
 		}
 		| macroargs T_STRING {
-			macro_AppendArg($$, strdup($2));
+			$$->append(strdup($2));
 		}
 ;
 
@@ -705,7 +709,7 @@ assert_type	: %empty { $$ = ASSERT_ERROR; }
 ;
 
 assert		: T_POP_ASSERT assert_type relocexpr {
-			if (!rpn_isKnown(&$3)) {
+			if (!$3.isKnown) {
 				out_CreateAssert($2, &$3, "", sect_GetOutputOffset());
 			} else if ($3.val == 0) {
 				failAssert($2);
@@ -713,7 +717,7 @@ assert		: T_POP_ASSERT assert_type relocexpr {
 			rpn_Free(&$3);
 		}
 		| T_POP_ASSERT assert_type relocexpr T_COMMA string {
-			if (!rpn_isKnown(&$3)) {
+			if (!$3.isKnown) {
 				out_CreateAssert($2, &$3, $5, sect_GetOutputOffset());
 			} else if ($3.val == 0) {
 				failAssertMsg($2, $5);
@@ -1256,13 +1260,13 @@ uconst		: const {
 		}
 ;
 
-const		: relocexpr { $$ = rpn_GetConstVal(&$1); }
+const		: relocexpr { $$ = $1.getConstVal(); }
 ;
 
-const_no_str	: relocexpr_no_str { $$ = rpn_GetConstVal(&$1); }
+const_no_str	: relocexpr_no_str { $$ = $1.getConstVal(); }
 ;
 
-const_8bit	: reloc_8bit { $$ = rpn_GetConstVal(&$1); }
+const_8bit	: reloc_8bit { $$ = $1.getConstVal(); }
 ;
 
 opt_q_arg	: %empty { $$ = fix_Precision(); }
@@ -1319,7 +1323,7 @@ string		: T_STRING
 
 			if (!sym)
 				fatalerror("Unknown symbol \"%s\"\n", $3);
-			Section const *section = sym_GetSection(sym);
+			Section const *section = sym->getSection();
 
 			if (!section)
 				fatalerror("\"%s\" does not belong to any section\n", sym->name);
@@ -1605,7 +1609,7 @@ z80_ldio	: T_Z80_LDH T_MODE_A T_COMMA op_mem_ind {
 
 c_ind		: T_LBRACK T_MODE_C T_RBRACK
 		| T_LBRACK relocexpr T_OP_ADD T_MODE_C T_RBRACK {
-			if (!rpn_isKnown(&$2) || $2.val != 0xFF00)
+			if (!$2.isKnown || $2.val != 0xFF00)
 				error("Expected constant expression equal to $FF00 for \"$ff00+c\"\n");
 		}
 ;
@@ -1642,7 +1646,7 @@ z80_ld_mem	: T_Z80_LD op_mem_ind T_COMMA T_MODE_SP {
 			sect_RelWord(&$2, 1);
 		}
 		| T_Z80_LD op_mem_ind T_COMMA T_MODE_A {
-			if (optimizeLoads && rpn_isKnown(&$2)
+			if (optimizeLoads && $2.isKnown
 			 && $2.val >= 0xFF00) {
 				if (warnOnLdOpt) {
 					warnOnLdOpt = false;
@@ -1695,8 +1699,7 @@ z80_ld_a	: T_Z80_LD reg_r T_COMMA c_ind {
 		}
 		| T_Z80_LD reg_r T_COMMA op_mem_ind {
 			if ($2 == REG_A) {
-				if (optimizeLoads && rpn_isKnown(&$4)
-				 && $4.val >= 0xFF00) {
+				if (optimizeLoads && $4.isKnown && $4.val >= 0xFF00) {
 					if (warnOnLdOpt) {
 						warnOnLdOpt = false;
 						warning(WARNING_OBSOLETE,
@@ -1795,7 +1798,7 @@ z80_rrca	: T_Z80_RRCA { sect_AbsByte(0x0F); }
 
 z80_rst		: T_Z80_RST reloc_8bit {
 			rpn_CheckRST(&$2, &$2);
-			if (!rpn_isKnown(&$2))
+			if (!$2.isKnown)
 				sect_RelByte(&$2, 0);
 			else
 				sect_AbsByte(0xC7 | $2.val);
@@ -2197,14 +2200,14 @@ static void freeStrFmtArgList(StrFmtArgList *args)
 	delete args->args;
 }
 
-static void strfmt(char *dest, size_t destLen, char const *fmt,
+static void strfmt(char *dest, size_t destLen, char const *spec,
 		   std::vector<std::variant<uint32_t, char *>> &args)
 {
 	size_t a = 0;
 	size_t i = 0;
 
 	while (i < destLen) {
-		int c = *fmt++;
+		int c = *spec++;
 
 		if (c == '\0') {
 			break;
@@ -2213,27 +2216,27 @@ static void strfmt(char *dest, size_t destLen, char const *fmt,
 			continue;
 		}
 
-		c = *fmt++;
+		c = *spec++;
 
 		if (c == '%') {
 			dest[i++] = c;
 			continue;
 		}
 
-		FormatSpec spec = fmt_NewSpec();
+		FormatSpec fmt{};
 
 		while (c != '\0') {
-			fmt_UseCharacter(&spec, c);
-			if (fmt_IsFinished(&spec))
+			fmt.useCharacter(c);
+			if (fmt.isFinished())
 				break;
-			c = *fmt++;
+			c = *spec++;
 		}
 
-		if (fmt_IsEmpty(&spec)) {
+		if (fmt.isEmpty()) {
 			error("STRFMT: Illegal '%%' at end of format string\n");
 			dest[i++] = '%';
 			break;
-		} else if (!fmt_IsValid(&spec)) {
+		} else if (!fmt.isValid()) {
 			error("STRFMT: Invalid format spec for argument %zu\n", a + 1);
 			dest[i++] = '%';
 			a++;
@@ -2249,8 +2252,8 @@ static void strfmt(char *dest, size_t destLen, char const *fmt,
 		static char buf[MAXSTRLEN + 1];
 
 		std::visit(Visitor{
-			[&](uint32_t num) { fmt_PrintNumber(buf, sizeof(buf), &spec, num); },
-			[&](char *str) { fmt_PrintString(buf, sizeof(buf), &spec, str); },
+			[&](uint32_t num) { fmt.printNumber(buf, sizeof(buf), num); },
+			[&](char *str) { fmt.printString(buf, sizeof(buf), str); },
 		}, arg);
 
 		i += snprintf(&dest[i], destLen - i, "%s", buf);
@@ -2277,7 +2280,7 @@ static void compoundAssignment(const char *symName, enum RPNCommand op, int32_t
 	rpn_Symbol(&oldExpr, symName);
 	rpn_Number(&constExpr, constValue);
 	rpn_BinaryOp(op, &newExpr, &oldExpr, &constExpr);
-	newValue = rpn_GetConstVal(&newExpr);
+	newValue = newExpr.getConstVal();
 	sym_AddVar(symName, newValue);
 }
 
diff --git a/src/asm/rpn.cpp b/src/asm/rpn.cpp
index 59a7bfcf..64f33089 100644
--- a/src/asm/rpn.cpp
+++ b/src/asm/rpn.cpp
@@ -21,6 +21,16 @@
 
 #include "opmath.hpp"
 
+// Init a RPN expression
+static void initExpression(Expression *expr)
+{
+	expr->reason = nullptr;
+	expr->isKnown = true;
+	expr->isSymbol = false;
+	expr->rpn = nullptr;
+	expr->rpnPatchSize = 0;
+}
+
 // Makes an expression "not known", also setting its error message
 template<typename... Ts>
 static void makeUnknown(Expression *expr, Ts ...parts)
@@ -46,28 +56,18 @@ static uint8_t *reserveSpace(Expression *expr, uint32_t size)
 	return &(*expr->rpn)[curSize];
 }
 
-// Init a RPN expression
-static void rpn_Init(Expression *expr)
-{
-	expr->reason = nullptr;
-	expr->isKnown = true;
-	expr->isSymbol = false;
-	expr->rpn = nullptr;
-	expr->rpnPatchSize = 0;
-}
-
 // Free the RPN expression
 void rpn_Free(Expression *expr)
 {
 	delete expr->rpn;
 	delete expr->reason;
-	rpn_Init(expr);
+	initExpression(expr);
 }
 
 // Add symbols, constants and operators to expression
 void rpn_Number(Expression *expr, uint32_t i)
 {
-	rpn_Init(expr);
+	initExpression(expr);
 	expr->val = i;
 }
 
@@ -78,8 +78,8 @@ void rpn_Symbol(Expression *expr, char const *symName)
 	if (sym_IsPC(sym) && !sect_GetSymbolSection()) {
 		error("PC has no value outside a section\n");
 		rpn_Number(expr, 0);
-	} else if (!sym || !sym_IsConstant(sym)) {
-		rpn_Init(expr);
+	} else if (!sym || !sym->isConstant()) {
+		initExpression(expr);
 		expr->isSymbol = true;
 
 		if (sym_IsPC(sym))
@@ -100,7 +100,7 @@ void rpn_Symbol(Expression *expr, char const *symName)
 
 void rpn_BankSelf(Expression *expr)
 {
-	rpn_Init(expr);
+	initExpression(expr);
 
 	if (!currentSection) {
 		error("PC has no bank outside a section\n");
@@ -124,22 +124,23 @@ void rpn_BankSymbol(Expression *expr, char const *symName)
 		return;
 	}
 
-	rpn_Init(expr);
-	if (sym && !sym_IsLabel(sym)) {
+	initExpression(expr);
+	if (sym && !sym->isLabel()) {
 		error("BANK argument must be a label\n");
 	} else {
 		sym = sym_Ref(symName);
 		assert(sym); // If the symbol didn't exist, it should have been created
 
-		if (sym_GetSection(sym) && sym_GetSection(sym)->bank != (uint32_t)-1) {
+		if (sym->getSection() && sym->getSection()->bank != (uint32_t)-1) {
 			// Symbol's section is known and bank is fixed
-			expr->val = sym_GetSection(sym)->bank;
+			expr->val = sym->getSection()->bank;
 		} else {
 			makeUnknown(expr, "\"", symName, "\"'s bank is not known");
 			expr->rpnPatchSize += 5; // opcode + 4-byte sect ID
 
 			size_t nameLen = strlen(sym->name) + 1; // Room for NUL!
 			uint8_t *ptr = reserveSpace(expr, nameLen + 1);
+
 			*ptr++ = RPN_BANK_SYM;
 			memcpy(ptr, sym->name, nameLen);
 		}
@@ -148,7 +149,7 @@ void rpn_BankSymbol(Expression *expr, char const *symName)
 
 void rpn_BankSection(Expression *expr, char const *sectionName)
 {
-	rpn_Init(expr);
+	initExpression(expr);
 
 	Section *section = sect_FindSectionByName(sectionName);
 
@@ -168,11 +169,11 @@ void rpn_BankSection(Expression *expr, char const *sectionName)
 
 void rpn_SizeOfSection(Expression *expr, char const *sectionName)
 {
-	rpn_Init(expr);
+	initExpression(expr);
 
 	Section *section = sect_FindSectionByName(sectionName);
 
-	if (section && sect_IsSizeKnown(section)) {
+	if (section && section->isSizeKnown()) {
 		expr->val = section->size;
 	} else {
 		makeUnknown(expr, "Section \"", sectionName, "\"'s size is not known");
@@ -188,7 +189,7 @@ void rpn_SizeOfSection(Expression *expr, char const *sectionName)
 
 void rpn_StartOfSection(Expression *expr, char const *sectionName)
 {
-	rpn_Init(expr);
+	initExpression(expr);
 
 	Section *section = sect_FindSectionByName(sectionName);
 
@@ -208,7 +209,7 @@ void rpn_StartOfSection(Expression *expr, char const *sectionName)
 
 void rpn_SizeOfSectionType(Expression *expr, enum SectionType type)
 {
-	rpn_Init(expr);
+	initExpression(expr);
 	makeUnknown(expr, "Section type's size is not known");
 
 	uint8_t *ptr = reserveSpace(expr, 2);
@@ -220,7 +221,7 @@ void rpn_SizeOfSectionType(Expression *expr, enum SectionType type)
 
 void rpn_StartOfSectionType(Expression *expr, enum SectionType type)
 {
-	rpn_Init(expr);
+	initExpression(expr);
 	makeUnknown(expr, "Section type's start is not known");
 
 	uint8_t *ptr = reserveSpace(expr, 2);
@@ -235,7 +236,7 @@ void rpn_CheckHRAM(Expression *expr, const Expression *src)
 	*expr = *src;
 	expr->isSymbol = false;
 
-	if (!rpn_isKnown(expr)) {
+	if (!expr->isKnown) {
 		expr->rpnPatchSize++;
 		*reserveSpace(expr, 1) = RPN_HRAM;
 	} else if (expr->val >= 0xFF00 && expr->val <= 0xFFFF) {
@@ -250,7 +251,7 @@ void rpn_CheckRST(Expression *expr, const Expression *src)
 {
 	*expr = *src;
 
-	if (rpn_isKnown(expr)) {
+	if (expr->isKnown) {
 		// A valid RST address must be masked with 0x38
 		if (expr->val & ~0x38)
 			error("Invalid address $%" PRIx32 " for RST\n", expr->val);
@@ -268,7 +269,7 @@ void rpn_CheckNBit(Expression const *expr, uint8_t n)
 	assert(n != 0); // That doesn't make sense
 	assert(n < CHAR_BIT * sizeof(int)); // Otherwise `1 << n` is UB
 
-	if (rpn_isKnown(expr)) {
+	if (expr->isKnown) {
 		int32_t val = expr->val;
 
 		if (val < -(1 << n) || val >= 1 << n)
@@ -278,13 +279,13 @@ void rpn_CheckNBit(Expression const *expr, uint8_t n)
 	}
 }
 
-int32_t rpn_GetConstVal(Expression const *expr)
+int32_t Expression::getConstVal() const
 {
-	if (!rpn_isKnown(expr)) {
-		error("Expected constant expression: %s\n", expr->reason->c_str());
+	if (!isKnown) {
+		error("Expected constant expression: %s\n", reason->c_str());
 		return 0;
 	}
-	return expr->val;
+	return val;
 }
 
 void rpn_LOGNOT(Expression *expr, const Expression *src)
@@ -292,7 +293,7 @@ void rpn_LOGNOT(Expression *expr, const Expression *src)
 	*expr = *src;
 	expr->isSymbol = false;
 
-	if (rpn_isKnown(expr)) {
+	if (expr->isKnown) {
 		expr->val = !expr->val;
 	} else {
 		expr->rpnPatchSize++;
@@ -300,31 +301,26 @@ void rpn_LOGNOT(Expression *expr, const Expression *src)
 	}
 }
 
-Symbol const *rpn_SymbolOf(Expression const *expr)
+Symbol const *Expression::symbolOf() const
 {
-	if (!rpn_isSymbol(expr))
+	if (!isSymbol)
 		return nullptr;
-	return sym_FindScopedSymbol((char const *)&(*expr->rpn)[1]);
+	return sym_FindScopedSymbol((char const *)&(*rpn)[1]);
 }
 
-bool rpn_IsDiffConstant(Expression const *src, Symbol const *sym)
+bool Expression::isDiffConstant(Symbol const *sym) const
 {
 	// Check if both expressions only refer to a single symbol
-	Symbol const *sym1 = rpn_SymbolOf(src);
+	Symbol const *sym1 = symbolOf();
 
 	if (!sym1 || !sym || sym1->type != SYM_LABEL || sym->type != SYM_LABEL)
 		return false;
 
-	Section const *section1 = sym_GetSection(sym1);
-	Section const *section2 = sym_GetSection(sym);
+	Section const *section1 = sym1->getSection();
+	Section const *section2 = sym->getSection();
 	return section1 && (section1 == section2);
 }
 
-static bool isDiffConstant(Expression const *src1, Expression const *src2)
-{
-	return rpn_IsDiffConstant(src1, rpn_SymbolOf(src2));
-}
-
 /*
  * Attempts to compute a constant binary AND from non-constant operands
  * This is possible if one operand is a symbol belonging to an `ALIGN[N]` section, and the other is
@@ -334,33 +330,33 @@ static bool isDiffConstant(Expression const *src1, Expression const *src2)
  */
 static int32_t tryConstMask(Expression const *lhs, Expression const *rhs)
 {
-	Symbol const *sym = rpn_SymbolOf(lhs);
+	Symbol const *sym = lhs->symbolOf();
 	Expression const *expr = rhs;
 
-	if (!sym || !sym_GetSection(sym)) {
+	if (!sym || !sym->getSection()) {
 		// If the lhs isn't a symbol, try again the other way around
-		sym = rpn_SymbolOf(rhs);
+		sym = rhs->symbolOf();
 		expr = lhs;
 
-		if (!sym || !sym_GetSection(sym))
+		if (!sym || !sym->getSection())
 			return -1;
 	}
-	assert(sym_IsNumeric(sym));
+	assert(sym->isNumeric());
 
-	if (!rpn_isKnown(expr))
+	if (!expr->isKnown)
 		return -1;
 	// We can now safely use `expr->val`
-	Section const *sect = sym_GetSection(sym);
+	Section const *sect = sym->getSection();
 	int32_t unknownBits = (1 << 16) - (1 << sect->align); // The max alignment is 16
 
 	// The mask must ignore all unknown bits
 	if ((expr->val & unknownBits) != 0)
 		return -1;
 
-	// `sym_GetValue()` attempts to add the section's address,
-	// but that's "-1" because the section is floating (otherwise we wouldn't be here)
+	// `sym->getValue()` attempts to add the section's address, but that's "-1"
+	// because the section is floating (otherwise we wouldn't be here)
 	assert(sect->org == (uint32_t)-1);
-	int32_t symbolOfs = sym_GetValue(sym) + 1;
+	int32_t symbolOfs = sym->getValue() + 1;
 
 	return (symbolOfs + sect->alignOfs) & ~unknownBits;
 }
@@ -371,9 +367,9 @@ void rpn_BinaryOp(enum RPNCommand op, Expression *expr, const Expression *src1,
 	int32_t constMaskVal;
 
 	// First, check if the expression is known
-	expr->isKnown = rpn_isKnown(src1) && rpn_isKnown(src2);
-	if (rpn_isKnown(expr)) {
-		rpn_Init(expr); // Init the expression to something sane
+	expr->isKnown = src1->isKnown && src2->isKnown;
+	if (expr->isKnown) {
+		initExpression(expr); // Init the expression to something sane
 
 		// If both expressions are known, just compute the value
 		uint32_t uleft = src1->val, uright = src2->val;
@@ -509,11 +505,11 @@ void rpn_BinaryOp(enum RPNCommand op, Expression *expr, const Expression *src1,
 			fatalerror("%d is not a binary operator\n", op);
 		}
 
-	} else if (op == RPN_SUB && isDiffConstant(src1, src2)) {
-		Symbol const *symbol1 = rpn_SymbolOf(src1);
-		Symbol const *symbol2 = rpn_SymbolOf(src2);
+	} else if (op == RPN_SUB && src1->isDiffConstant(src2->symbolOf())) {
+		Symbol const *symbol1 = src1->symbolOf();
+		Symbol const *symbol2 = src2->symbolOf();
 
-		expr->val = sym_GetValue(symbol1) - sym_GetValue(symbol2);
+		expr->val = symbol1->getValue() - symbol2->getValue();
 		expr->isKnown = true;
 	} else if (op == RPN_AND && (constMaskVal = tryConstMask(src1, src2)) != -1) {
 		expr->val = constMaskVal;
@@ -522,7 +518,7 @@ void rpn_BinaryOp(enum RPNCommand op, Expression *expr, const Expression *src1,
 		// If it's not known, start computing the RPN expression
 
 		// Convert the left-hand expression if it's constant
-		if (rpn_isKnown(src1)) {
+		if (src1->isKnown) {
 			uint32_t lval = src1->val;
 			uint8_t bytes[] = {RPN_CONST, (uint8_t)lval, (uint8_t)(lval >> 8),
 					   (uint8_t)(lval >> 16), (uint8_t)(lval >> 24)};
@@ -550,7 +546,7 @@ void rpn_BinaryOp(enum RPNCommand op, Expression *expr, const Expression *src1,
 		uint32_t rval = src2->val;
 		uint8_t bytes[] = {RPN_CONST, (uint8_t)rval, (uint8_t)(rval >> 8),
 				   (uint8_t)(rval >> 16), (uint8_t)(rval >> 24)};
-		if (rpn_isKnown(src2)) {
+		if (src2->isKnown) {
 			ptr = bytes;
 			len = sizeof(bytes);
 			patchSize = sizeof(bytes);
@@ -577,7 +573,7 @@ void rpn_HIGH(Expression *expr, const Expression *src)
 	*expr = *src;
 	expr->isSymbol = false;
 
-	if (rpn_isKnown(expr)) {
+	if (expr->isKnown) {
 		expr->val = (uint32_t)expr->val >> 8 & 0xFF;
 	} else {
 		uint8_t bytes[] = {RPN_CONST,    8, 0, 0, 0, RPN_SHR,
@@ -592,7 +588,7 @@ void rpn_LOW(Expression *expr, const Expression *src)
 	*expr = *src;
 	expr->isSymbol = false;
 
-	if (rpn_isKnown(expr)) {
+	if (expr->isKnown) {
 		expr->val = expr->val & 0xFF;
 	} else {
 		uint8_t bytes[] = {RPN_CONST, 0xFF, 0, 0, 0, RPN_AND};
@@ -604,8 +600,8 @@ void rpn_LOW(Expression *expr, const Expression *src)
 
 void rpn_ISCONST(Expression *expr, const Expression *src)
 {
-	rpn_Init(expr);
-	expr->val = rpn_isKnown(src);
+	initExpression(expr);
+	expr->val = src->isKnown;
 	expr->isKnown = true;
 	expr->isSymbol = false;
 }
@@ -615,7 +611,7 @@ void rpn_NEG(Expression *expr, const Expression *src)
 	*expr = *src;
 	expr->isSymbol = false;
 
-	if (rpn_isKnown(expr)) {
+	if (expr->isKnown) {
 		expr->val = -(uint32_t)expr->val;
 	} else {
 		expr->rpnPatchSize++;
@@ -628,7 +624,7 @@ void rpn_NOT(Expression *expr, const Expression *src)
 	*expr = *src;
 	expr->isSymbol = false;
 
-	if (rpn_isKnown(expr)) {
+	if (expr->isKnown) {
 		expr->val = ~expr->val;
 	} else {
 		expr->rpnPatchSize++;
diff --git a/src/asm/section.cpp b/src/asm/section.cpp
index 352c4b1d..770af789 100644
--- a/src/asm/section.cpp
+++ b/src/asm/section.cpp
@@ -250,7 +250,7 @@ static void mergeSections(Section *sect, enum SectionType type, uint32_t org, ui
 
 		case SECTION_NORMAL:
 			fail("Section already defined previously at ");
-			fstk_Dump(sect->src, sect->fileLine);
+			sect->src->dump(sect->fileLine);
 			putc('\n', stderr);
 			break;
 		}
@@ -375,6 +375,25 @@ static void changeSection()
 	sym_SetCurrentSymbolScope(nullptr);
 }
 
+bool Section::isSizeKnown() const
+{
+	// SECTION UNION and SECTION FRAGMENT can still grow
+	if (modifier != SECTION_NORMAL)
+		return false;
+
+	// The current section (or current load section if within one) is still growing
+	if (this == currentSection || this == currentLoadSection)
+		return false;
+
+	// Any section on the stack is still growing
+	for (SectionStackEntry &entry : sectionStack) {
+		if (entry.section && !strcmp(name, entry.section->name))
+			return false;
+	}
+
+	return true;
+}
+
 // Set the current section by name and type
 void sect_NewSection(char const *name, enum SectionType type, uint32_t org,
 		     SectionSpec const *attribs, enum SectionModifier mod)
@@ -675,7 +694,7 @@ void sect_RelByte(Expression *expr, uint32_t pcShift)
 	if (!reserveSpace(1))
 		return;
 
-	if (!rpn_isKnown(expr)) {
+	if (!expr->isKnown) {
 		createPatch(PATCHTYPE_BYTE, expr, pcShift);
 		writebyte(0);
 	} else {
@@ -696,7 +715,7 @@ void sect_RelBytes(uint32_t n, std::vector<Expression> &exprs)
 	for (uint32_t i = 0; i < n; i++) {
 		Expression &expr = exprs[i % exprs.size()];
 
-		if (!rpn_isKnown(&expr)) {
+		if (!expr.isKnown) {
 			createPatch(PATCHTYPE_BYTE, &expr, i);
 			writebyte(0);
 		} else {
@@ -717,7 +736,7 @@ void sect_RelWord(Expression *expr, uint32_t pcShift)
 	if (!reserveSpace(2))
 		return;
 
-	if (!rpn_isKnown(expr)) {
+	if (!expr->isKnown) {
 		createPatch(PATCHTYPE_WORD, expr, pcShift);
 		writeword(0);
 	} else {
@@ -735,7 +754,7 @@ void sect_RelLong(Expression *expr, uint32_t pcShift)
 	if (!reserveSpace(2))
 		return;
 
-	if (!rpn_isKnown(expr)) {
+	if (!expr->isKnown) {
 		createPatch(PATCHTYPE_LONG, expr, pcShift);
 		writelong(0);
 	} else {
@@ -754,11 +773,11 @@ void sect_PCRelByte(Expression *expr, uint32_t pcShift)
 		return;
 	Symbol const *pc = sym_GetPC();
 
-	if (!rpn_IsDiffConstant(expr, pc)) {
+	if (!expr->isDiffConstant(pc)) {
 		createPatch(PATCHTYPE_JR, expr, pcShift);
 		writebyte(0);
 	} else {
-		Symbol const *sym = rpn_SymbolOf(expr);
+		Symbol const *sym = expr->symbolOf();
 		// The offset wraps (jump from ROM to HRAM, for example)
 		int16_t offset;
 
@@ -766,7 +785,7 @@ void sect_PCRelByte(Expression *expr, uint32_t pcShift)
 		if (sym == pc)
 			offset = -2; // PC as operand to `jr` is lower than reference PC by 2
 		else
-			offset = sym_GetValue(sym) - (sym_GetValue(pc) + 1);
+			offset = sym->getValue() - (pc->getValue() + 1);
 
 		if (offset < -128 || offset > 127) {
 			error("jr target out of reach (expected -129 < %" PRId16 " < 128)\n",
@@ -973,22 +992,3 @@ void sect_EndSection()
 	currentSection = nullptr;
 	sym_SetCurrentSymbolScope(nullptr);
 }
-
-bool sect_IsSizeKnown(Section const NONNULL(sect))
-{
-	// SECTION UNION and SECTION FRAGMENT can still grow
-	if (sect->modifier != SECTION_NORMAL)
-		return false;
-
-	// The current section (or current load section if within one) is still growing
-	if (sect == currentSection || sect == currentLoadSection)
-		return false;
-
-	// Any section on the stack is still growing
-	for (SectionStackEntry &entry : sectionStack) {
-		if (entry.section && !strcmp(sect->name, entry.section->name))
-			return false;
-	}
-
-	return true;
-}
diff --git a/src/asm/symbol.cpp b/src/asm/symbol.cpp
index d82eaf7e..ca280333 100644
--- a/src/asm/symbol.cpp
+++ b/src/asm/symbol.cpp
@@ -66,22 +66,22 @@ static int32_t CallbackPC()
 }
 
 // Get the value field of a symbol
-int32_t sym_GetValue(Symbol const *sym)
+int32_t Symbol::getValue() const
 {
-	if (sym_IsNumeric(sym) && sym->hasCallback)
-		return sym->numCallback();
+	if (isNumeric() && hasCallback)
+		return numCallback();
 
-	if (sym->type == SYM_LABEL)
+	if (type == SYM_LABEL)
 		// TODO: do not use section's org directly
-		return sym->value + sym_GetSection(sym)->org;
+		return value + getSection()->org;
 
-	return sym->value;
+	return value;
 }
 
 static void dumpFilename(Symbol const *sym)
 {
 	if (sym->src)
-		fstk_Dump(sym->src, sym->fileLine);
+		sym->src->dump(sym->fileLine);
 	else if (sym->fileLine == 0)
 		fputs("<command-line>", stderr);
 	else
@@ -178,7 +178,7 @@ Symbol *sym_FindScopedValidSymbol(char const *symName)
 	Symbol *sym = sym_FindScopedSymbol(symName);
 
 	// `@` has no value outside a section
-	if (sym == PCSymbol && !sect_GetSymbolSection()) {
+	if (sym_IsPC(sym) && !sect_GetSymbolSection()) {
 		return nullptr;
 	}
 	// `_NARG` has no value outside a macro
@@ -235,28 +235,25 @@ uint32_t sym_GetPCValue()
 }
 
 // Return a constant symbol's value, assuming it's defined
-uint32_t sym_GetConstantSymValue(Symbol const *sym)
+uint32_t Symbol::getConstantValue() const
 {
-	if (sym == PCSymbol)
+	if (sym_IsPC(this))
 		return sym_GetPCValue();
-	else if (!sym_IsConstant(sym))
-		error("\"%s\" does not have a constant value\n", sym->name);
-	else
-		return sym_GetValue(sym);
 
+	if (isConstant())
+		return getValue();
+
+	error("\"%s\" does not have a constant value\n", name);
 	return 0;
 }
 
 // Return a constant symbol's value
 uint32_t sym_GetConstantValue(char const *symName)
 {
-	Symbol const *sym = sym_FindScopedSymbol(symName);
-
-	if (!sym)
-		error("'%s' not defined\n", symName);
-	else
-		return sym_GetConstantSymValue(sym);
+	if (Symbol const *sym = sym_FindScopedSymbol(symName); sym)
+		return sym->getConstantValue();
 
+	error("'%s' not defined\n", symName);
 	return 0;
 }
 
@@ -283,7 +280,7 @@ static Symbol *createNonrelocSymbol(char const *symName, bool numeric)
 
 	if (!sym) {
 		sym = createsymbol(symName);
-	} else if (sym_IsDefined(sym)) {
+	} else if (sym->isDefined()) {
 		error("'%s' already defined at ", symName);
 		dumpFilename(sym);
 		putc('\n', stderr);
@@ -320,7 +317,7 @@ Symbol *sym_RedefEqu(char const *symName, int32_t value)
 	if (!sym)
 		return sym_AddEqu(symName, value);
 
-	if (sym_IsDefined(sym) && sym->type != SYM_EQU) {
+	if (sym->isDefined() && sym->type != SYM_EQU) {
 		error("'%s' already defined as non-EQU at ", symName);
 		dumpFilename(sym);
 		putc('\n', stderr);
@@ -368,7 +365,7 @@ Symbol *sym_RedefString(char const *symName, char const *value)
 		return sym_AddString(symName, value);
 
 	if (sym->type != SYM_EQUS) {
-		if (sym_IsDefined(sym))
+		if (sym->isDefined())
 			error("'%s' already defined as non-EQUS at ", symName);
 		else
 			error("'%s' already referenced at ", symName);
@@ -395,7 +392,7 @@ Symbol *sym_AddVar(char const *symName, int32_t value)
 
 	if (!sym) {
 		sym = createsymbol(symName);
-	} else if (sym_IsDefined(sym) && sym->type != SYM_VAR) {
+	} else if (sym->isDefined() && sym->type != SYM_VAR) {
 		error("'%s' already defined as %s at ",
 		      symName, sym->type == SYM_LABEL ? "label" : "constant");
 		dumpFilename(sym);
@@ -423,7 +420,7 @@ static Symbol *addLabel(char const *symName)
 
 	if (!sym) {
 		sym = createsymbol(symName);
-	} else if (sym_IsDefined(sym)) {
+	} else if (sym->isDefined()) {
 		error("'%s' already defined at ", symName);
 		dumpFilename(sym);
 		putc('\n', stderr);
diff --git a/src/link/main.cpp b/src/link/main.cpp
index 4c9f2e46..5a95c69e 100644
--- a/src/link/main.cpp
+++ b/src/link/main.cpp
@@ -72,23 +72,23 @@ std::string const &FileStackNode::name() const {
 }
 
 // Helper function to dump a file stack to stderr
-std::string const *dumpFileStack(FileStackNode const *node)
+std::string const *FileStackNode::dumpFileStack() const
 {
 	std::string const *lastName;
 
-	if (node->parent) {
-		lastName = dumpFileStack(node->parent);
+	if (parent) {
+		lastName = parent->dumpFileStack();
 		// REPT nodes use their parent's name
-		if (node->type != NODE_REPT)
-			lastName = &node->name();
-		fprintf(stderr, "(%" PRIu32 ") -> %s", node->lineNo, lastName->c_str());
-		if (node->type == NODE_REPT) {
-			for (uint32_t iter : node->iters())
+		if (type != NODE_REPT)
+			lastName = &name();
+		fprintf(stderr, "(%" PRIu32 ") -> %s", lineNo, lastName->c_str());
+		if (type == NODE_REPT) {
+			for (uint32_t iter : iters())
 				fprintf(stderr, "::REPT~%" PRIu32, iter);
 		}
 	} else {
-		assert(node->type != NODE_REPT);
-		lastName = &node->name();
+		assert(type != NODE_REPT);
+		lastName = &name();
 		fputs(lastName->c_str(), stderr);
 	}
 
@@ -101,7 +101,7 @@ void printDiag(char const *fmt, va_list args, char const *type,
 	fputs(type, stderr);
 	fputs(": ", stderr);
 	if (where) {
-		dumpFileStack(where);
+		where->dumpFileStack();
 		fprintf(stderr, "(%" PRIu32 "): ", lineNo);
 	}
 	vfprintf(stderr, fmt, args);
diff --git a/src/link/symbol.cpp b/src/link/symbol.cpp
index 5934faa4..a9971fd8 100644
--- a/src/link/symbol.cpp
+++ b/src/link/symbol.cpp
@@ -18,9 +18,9 @@ void sym_AddSymbol(Symbol *symbol)
 	// Check if the symbol already exists
 	if (Symbol *other = sym_GetSymbol(symbol->name); other) {
 		fprintf(stderr, "error: \"%s\" both in %s from ", symbol->name.c_str(), symbol->objFileName);
-		dumpFileStack(symbol->src);
+		symbol->src->dumpFileStack();
 		fprintf(stderr, "(%" PRIu32 ") and in %s from ", symbol->lineNo, other->objFileName);
-		dumpFileStack(other->src);
+		other->src->dumpFileStack();
 		fprintf(stderr, "(%" PRIu32 ")\n", other->lineNo);
 		exit(1);
 	}