Added object file format spec

This is a WIP.

doc/object_format.md

@@ -0,0 +1,55 @@
+# Linker file format
+
+```C
+
+struct object_file {
+    uint64_t    magic;   // ".oo-bin"
+    uint64_t    version; // 1
+    uint64_t    architecture; // AMD64(0)
+    uint64_t    offsets_offset;
+
+    struct offsets {
+        uint64_t strings;
+        uint64_t sections;
+        uint64_t symbols;
+        uint64_t relocations;
+    } offsets;
+
+    struct string_table {
+        uint64_t size;
+        uint8_t data[static size];
+    } strings;
+
+    struct section_table {
+        uint32_t count;
+        struct section_entry {
+            uint32_t name;
+            uint64_t offset;
+            uint64_t size_on_disk;
+            uint64_t size_in_memory;
+            uint64_t flags;
+        } sections[static count];
+    } sections;
+
+    struct symbol_table {
+        uint32_t count;
+        struct symbol_entry {
+            uint32_t name;
+            uint8_t  kind;  // IMPORT(0) | EXPORT(1) | LOCAL(2)
+            uint32_t section;
+            uint64_t offset;
+        } symbols[static count];
+    } symbols;
+
+    struct relocation_table {
+        uint32_t count;
+        struct relocation_entry {
+            uint32_t section;
+            uint64_t offset;
+            uint8_t  size;
+            uint32_t symbol;
+            uint8_t  kind;  // ABSOLUTE(0) | RELATIVE(1)
+        } relocations[static count];
+    } relocations;
+};
+```

src/ast.c

@@ -162,46 +162,26 @@ const char *ast_node_id_to_cstr(node_id_t id) {
     __builtin_unreachable();
 }
 
-/**
- * @brief Helper function to print a single AST node with indentation
- *
- * @param node The node to print
- * @param indent Current indentation level
- */
 static void ast_node_print_internal(ast_node_t *node, int indent) {
     if (node == NULL) {
         return;
     }
 
-    // Print indentation
     for (int i = 0; i < indent; i++) {
         printf("  ");
     }
-
-    // Print node type
     printf("%s", ast_node_id_to_cstr(node->id));
 
-    // Print token value if available
     if (node->token_entry && node->token_entry->token.value) {
         printf(" \"%s\"", node->token_entry->token.value);
     }
     printf("\n");
 
-    // Recursively print all children with increased indentation
     for (size_t i = 0; i < node->len; i++) {
         ast_node_print_internal(node->children[i], indent + 1);
     }
 }
 
-/**
- * @brief Prints an AST starting from the given node
- *
- * Prints a representation of the AST with indentation to show structure.
- * Each node's type is shown, and if a node has an associated token value,
- * that value is printed in quotes.
- *
- * @param node The root node of the AST to print
- */
 void ast_node_print(ast_node_t *node) {
     ast_node_print_internal(node, 0);
 }

src/ast.h

@@ -106,7 +106,15 @@ void ast_node_free(ast_node_t *node);
  */
 error_t *ast_node_add_child(ast_node_t *node, ast_node_t *child);
 
-const char *ast_node_id_to_cstr(node_id_t id);
+/**
+ * @brief Prints an AST starting from the given node
+ *
+ * Prints a representation of the AST with indentation to show structure.
+ * Each node's type is shown, and if a node has an associated token value,
+ * that value is printed in quotes.
+ *
+ * @param node The root node of the AST to print
+ */
 void ast_node_print(ast_node_t *node);
 
 #endif // INCLUDE_SRC_AST_H_

src/main.c

@@ -1,6 +1,6 @@
 #include "error.h"
 #include "lexer.h"
-#include "parser.h"
+#include "parser/parser.h"
 #include "tokenlist.h"
 
 #include <limits.h>

src/parser.c

@@ -1,53 +0,0 @@
-#include "parser.h"
-#include "ast.h"
-#include "lexer.h"
-#include "parser_combinators.h"
-#include "parser_primitives.h"
-#include "parser_util.h"
-#include "tokenlist.h"
-
-parse_result_t parse_number(tokenlist_entry_t *current) {
-    parser_t parsers[] = {parse_octal, parse_decimal, parse_hexadecimal,
-                          parse_binary, nullptr};
-    return parse_any(current, parsers);
-}
-
-parse_result_t parse_operand(tokenlist_entry_t *current) {
-    // FIXME: not the correct set of parsers
-    parser_t parsers[] = {parse_register, parse_number, nullptr};
-    return parse_any(current, parsers);
-}
-
-parse_result_t parse_operands(tokenlist_entry_t *current) {
-    return parse_list(current, NODE_OPERANDS, true, TOKEN_COMMA, parse_operand);
-}
-
-parse_result_t parse_label(tokenlist_entry_t *current) {
-    parser_t parsers[] = {parse_identifier, parse_colon, nullptr};
-    return parse_consecutive(current, NODE_LABEL, parsers);
-}
-
-parse_result_t parse_section_directive(tokenlist_entry_t *current) {
-    parser_t parsers[] = {parse_section, parse_identifier, nullptr};
-    return parse_consecutive(current, NODE_SECTION_DIRECTIVE, parsers);
-}
-
-parse_result_t parse_directive(tokenlist_entry_t *current) {
-    parser_t parsers[] = {parse_dot, parse_section_directive, nullptr};
-    return parse_consecutive(current, NODE_DIRECTIVE, parsers);
-}
-
-parse_result_t parse_instruction(tokenlist_entry_t *current) {
-    parser_t parsers[] = {parse_identifier, parse_operands, nullptr};
-    return parse_consecutive(current, NODE_INSTRUCTION, parsers);
-}
-
-parse_result_t parse_statement(tokenlist_entry_t *current) {
-    parser_t parsers[] = {parse_label, parse_directive, parse_instruction,
-                          nullptr};
-    return parse_any(current, parsers);
-}
-
-parse_result_t parse(tokenlist_entry_t *current) {
-    return parse_many(current, NODE_PROGRAM, true, parse_statement);
-}

src/parser.h

@@ -1,11 +0,0 @@
-#ifndef INCLUDE_SRC_PARSER_H_
-#define INCLUDE_SRC_PARSER_H_
-
-#include "ast.h"
-#include "error.h"
-#include "parser_util.h"
-#include "tokenlist.h"
-
-parse_result_t parse(tokenlist_entry_t *current);
-
-#endif // INCLUDE_SRC_PARSER_H_

src/parser/combinators.c

@@ -1,4 +1,4 @@
-#include "parser_combinators.h"
+#include "combinators.h"
 
 // Parse a list of the given parser delimited by the given token id. Does not
 // store the delimiters in the parent node

src/parser/combinators.h

@@ -1,4 +1,7 @@
-#include "parser_util.h"
+#ifndef INCLUDE_PARSER_COMBINATORS_H_
+#define INCLUDE_PARSER_COMBINATORS_H_
+
+#include "util.h"
 
 typedef parse_result_t (*parser_t)(tokenlist_entry_t *);
 
@@ -18,3 +21,5 @@ parse_result_t parse_list(tokenlist_entry_t *current, node_id_t id,
 // wraps the parsed nodes in a new parent node.
 parse_result_t parse_consecutive(tokenlist_entry_t *current, node_id_t id,
                                  parser_t parsers[]);
+
+#endif // INCLUDE_PARSER_COMBINATORS_H_

src/parser/parser.c

@@ -0,0 +1,140 @@
+#include "parser.h"
+#include "../ast.h"
+#include "../lexer.h"
+#include "../tokenlist.h"
+#include "combinators.h"
+#include "primitives.h"
+#include "util.h"
+
+parse_result_t parse_number(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_octal, parse_decimal, parse_hexadecimal,
+                          parse_binary, nullptr};
+    parse_result_t result = parse_any(current, parsers);
+    return parse_result_wrap(NODE_NUMBER, result);
+}
+
+parse_result_t parse_plus_or_minus(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_plus, parse_minus, nullptr};
+    return parse_any(current, parsers);
+}
+
+parse_result_t parse_register_index(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_plus, parse_register, parse_asterisk,
+                          parse_number, nullptr};
+    return parse_consecutive(current, NODE_REGISTER_INDEX, parsers);
+}
+
+parse_result_t parse_register_offset(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_plus_or_minus, parse_number, nullptr};
+    return parse_consecutive(current, NODE_REGISTER_OFFSET, parsers);
+}
+
+parse_result_t parse_register_expression(tokenlist_entry_t *current) {
+    parse_result_t result;
+
+    ast_node_t *expr;
+    error_t *err = ast_node_alloc(&expr);
+    if (err)
+        return parse_error(err);
+    expr->id = NODE_REGISTER_EXPRESSION;
+
+    // <register>
+    result = parse_register(current);
+    if (result.err) {
+        ast_node_free(expr);
+        return result;
+    }
+    err = ast_node_add_child(expr, result.node);
+    if (err) {
+        ast_node_free(result.node);
+        ast_node_free(expr);
+        return parse_error(err);
+    }
+    current = result.next;
+
+    // <register_index>?
+    result = parse_register_index(current);
+    if (result.err) {
+        error_free(result.err);
+    } else {
+        err = ast_node_add_child(expr, result.node);
+        if (err) {
+            ast_node_free(result.node);
+            ast_node_free(expr);
+            return parse_error(err);
+        }
+        current = result.next;
+    }
+
+    // <register_offset>?
+    result = parse_register_offset(current);
+    if (result.err) {
+        error_free(result.err);
+    } else {
+        err = ast_node_add_child(expr, result.node);
+        if (err) {
+            ast_node_free(result.node);
+            ast_node_free(expr);
+            return parse_error(err);
+        }
+        current = result.next;
+    }
+    return parse_success(expr, current);
+}
+
+parse_result_t parse_immediate(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_number, parse_identifier, nullptr};
+    parse_result_t result = parse_any(current, parsers);
+    return parse_result_wrap(NODE_IMMEDIATE, result);
+}
+
+parse_result_t parse_memory_expression(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_register_expression, parse_identifier, nullptr};
+    return parse_any(current, parsers);
+}
+
+parse_result_t parse_memory(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_lbracket, parse_memory_expression,
+                          parse_rbracket, nullptr};
+    return parse_consecutive(current, NODE_MEMORY, parsers);
+}
+
+parse_result_t parse_operand(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_register, parse_memory, parse_immediate,
+                          nullptr};
+    return parse_any(current, parsers);
+}
+
+parse_result_t parse_operands(tokenlist_entry_t *current) {
+    return parse_list(current, NODE_OPERANDS, true, TOKEN_COMMA, parse_operand);
+}
+
+parse_result_t parse_label(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_identifier, parse_colon, nullptr};
+    return parse_consecutive(current, NODE_LABEL, parsers);
+}
+
+parse_result_t parse_section_directive(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_section, parse_identifier, nullptr};
+    return parse_consecutive(current, NODE_SECTION_DIRECTIVE, parsers);
+}
+
+parse_result_t parse_directive(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_dot, parse_section_directive, nullptr};
+    return parse_consecutive(current, NODE_DIRECTIVE, parsers);
+}
+
+parse_result_t parse_instruction(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_identifier, parse_operands, nullptr};
+    return parse_consecutive(current, NODE_INSTRUCTION, parsers);
+}
+
+parse_result_t parse_statement(tokenlist_entry_t *current) {
+    parser_t parsers[] = {parse_label, parse_directive, parse_instruction,
+                          nullptr};
+    return parse_any(current, parsers);
+}
+
+parse_result_t parse(tokenlist_entry_t *current) {
+    return parse_many(current, NODE_PROGRAM, true, parse_statement);
+}

src/parser/parser.h

@@ -0,0 +1,9 @@
+#ifndef INCLUDE_PARSER_PARSER_H_
+#define INCLUDE_PARSER_PARSER_H_
+
+#include "../tokenlist.h"
+#include "util.h"
+
+parse_result_t parse(tokenlist_entry_t *current);
+
+#endif // INCLUDE_PARSER_PARSER_H_

src/parser/primitives.c

@@ -1,5 +1,5 @@
-#include "parser_primitives.h"
+#include "primitives.h"
-#include "ast.h"
+#include "../ast.h"
 #include <string.h>
 
 parse_result_t parse_identifier(tokenlist_entry_t *current) {
@@ -62,6 +62,11 @@ parse_result_t parse_dot(tokenlist_entry_t *current) {
     return parse_token(current, TOKEN_DOT, NODE_DOT, nullptr);
 }
 
+parse_result_t parse_label_reference(tokenlist_entry_t *current) {
+    return parse_token(current, TOKEN_IDENTIFIER, NODE_LABEL_REFERENCE,
+                       nullptr);
+}
+
 const char *registers[] = {
     // 64-bit registers
     "rax", "rcx", "rdx", "rbx", "rsp", "rbp", "rsi", "rdi", "r8", "r9", "r10",
@@ -75,6 +80,7 @@ const char *registers[] = {
     // 8-bit low registers
     "al", "cl", "dl", "bl", "spl", "bpl", "sil", "dil", "r8b", "r9b", "r10b",
     "r11b", "r12b", "r13b", "r14b", "r15b", nullptr};
+
 bool is_register_token(lexer_token_t *token) {
     for (size_t i = 0; registers[i] != nullptr; ++i)
         if (strcmp(token->value, registers[i]) == 0)

src/parser/primitives.h

@@ -1,7 +1,7 @@
-#ifndef INCLUDE_SRC_PARSER_PRIMITIVES_H_
+#ifndef INCLUDE_PARSER_PRIMITIVES_H_
-#define INCLUDE_SRC_PARSER_PRIMITIVES_H_
+#define INCLUDE_PARSER_PRIMITIVES_H_
 
-#include "parser_util.h"
+#include "util.h"
 
 parse_result_t parse_identifier(tokenlist_entry_t *current);
 parse_result_t parse_decimal(tokenlist_entry_t *current);
@@ -18,6 +18,7 @@ parse_result_t parse_plus(tokenlist_entry_t *current);
 parse_result_t parse_minus(tokenlist_entry_t *current);
 parse_result_t parse_asterisk(tokenlist_entry_t *current);
 parse_result_t parse_dot(tokenlist_entry_t *current);
+parse_result_t parse_label_reference(tokenlist_entry_t *current);
 
 /* These are "primitives" with a different name and some extra validation on top
  * for example, register is just an identifier but it only matches a limited set
@@ -26,4 +27,4 @@ parse_result_t parse_dot(tokenlist_entry_t *current);
 parse_result_t parse_register(tokenlist_entry_t *current);
 parse_result_t parse_section(tokenlist_entry_t *current);
 
-#endif // INCLUDE_SRC_PARSER_PRIMITIVES_H_
+#endif // INCLUDE_PARSER_PRIMITIVES_H_

src/parser/util.c

@@ -1,5 +1,5 @@
-#include "parser_util.h"
+#include "util.h"
-#include "tokenlist.h"
+#include "../tokenlist.h"
 
 error_t *err_parse_no_match =
     &(error_t){.message = "parsing failed to find the correct token sequence"};
@@ -33,3 +33,24 @@ parse_result_t parse_token(tokenlist_entry_t *current,
 
     return parse_success(node, current->next);
 }
+
+parse_result_t parse_result_wrap(node_id_t id, parse_result_t result) {
+    if (result.err)
+        return result;
+
+    ast_node_t *node;
+    error_t *err = ast_node_alloc(&node);
+    if (err) {
+        ast_node_free(result.node);
+        return parse_error(err);
+    }
+    node->id = id;
+
+    err = ast_node_add_child(node, result.node);
+    if (err) {
+        ast_node_free(result.node);
+        return parse_error(err);
+    }
+
+    return parse_success(node, result.next);
+}

src/parser/util.h

@@ -1,9 +1,9 @@
-#ifndef INCLUDE_SRC_PARSER_UTIL_H_
+#ifndef INCLUDE_PARSER_UTIL_H_
-#define INCLUDE_SRC_PARSER_UTIL_H_
+#define INCLUDE_PARSER_UTIL_H_
 
-#include "ast.h"
+#include "../ast.h"
-#include "error.h"
+#include "../error.h"
-#include "tokenlist.h"
+#include "../tokenlist.h"
 
 typedef struct parse_result {
     error_t *err;
@@ -19,9 +19,8 @@ parse_result_t parse_success(ast_node_t *ast, tokenlist_entry_t *next);
 parse_result_t parse_token(tokenlist_entry_t *current,
                            lexer_token_id_t token_id, node_id_t ast_id,
                            token_validator_t is_valid);
-
+parse_result_t parse_result_wrap(node_id_t id, parse_result_t result);
-tokenlist_entry_t *skip_insignificant(tokenlist_entry_t *);
 
 extern error_t *err_parse_no_match;
 
-#endif // INCLUDE_SRC_PARSER_UTIL_H_
+#endif // INCLUDE_PARSER_UTIL_H_

tests/input/valid.asm

@@ -1,8 +1,17 @@
 .section text
 
+; Small valid code snippet that should contain all different AST nodes
+
 _start:
     mov eax, ebx
-    mov eax, 555            ; move 555 into eax
+    lea eax, [eax + ebx * 4 + 8]
+    lea eax, [eax + 8]
+    lea eax, [eax + ebx * 8]
+    lea eax, [esp - 24]
+    lea eax, [eax + ebx * 4 - 8]
+    lea eax, [_start]
+    mov eax, _start
+    mov eax, 555
     push 0o777
     xor eax, 0xDEADBEEF
     and ecx, 0o770