include and global works

asm/main.c

@@ -18,6 +18,12 @@ typedef struct {
     const char* output_file;
 } Args;
 
+typedef struct {
+    char* ident;
+    Loc loc;
+    uint16_t ip;
+} GlobalSym;
+
 static inline Args parse_args(int argc, char** argv);
 static inline char* read_text_file(const char* filename);
 static inline int include_file(IdentResolver* resolver,
@@ -60,22 +66,37 @@ int main(int argc, char** argv)
     PLine** lines = malloc(sizeof(PLine*) * lines_capacity);
     size_t lines_size = 0;
 
+    size_t global_symbols_capacity = 8;
+    GlobalSym* global_symbols
+        = malloc(sizeof(GlobalSym) * global_symbols_capacity);
+    size_t global_symbols_size = 0;
+
     while (!parser_done(&parser)) {
-        if (lines_size + 1 > lines_capacity) {
-            lines_capacity += 2;
-            lines = realloc(lines, sizeof(PLine*) * lines_capacity);
-        }
         PStmt* stmt = parser_next_stmt(&parser);
         if (!stmt) {
             continue;
         }
         switch (stmt->ty) {
             case PStmtTy_Line:
+                if (lines_size + 1 > lines_capacity) {
+                    lines_capacity *= 2;
+                    lines = realloc(lines, sizeof(PLine*) * lines_capacity);
+                }
                 lines[lines_size++] = stmt->line;
                 // NOTE: Shallow free.
                 free(stmt);
                 break;
             case PStmtTy_Global:
+                if (global_symbols_size + 1 > global_symbols_capacity) {
+                    global_symbols_capacity *= 2;
+                    global_symbols = realloc(global_symbols,
+                        sizeof(GlobalSym) * global_symbols_capacity);
+                }
+                global_symbols[global_symbols_size++] = (GlobalSym) {
+                    .ident = asm_strdup(stmt->ident),
+                    .loc = stmt->loc,
+                    .ip = 0,
+                };
                 pstmt_free(stmt);
                 break;
             case PStmtTy_Extern:
@@ -85,8 +106,17 @@ int main(int argc, char** argv)
                 const IdentResol* existing
                     = ident_resolver_resolve(&resolver, stmt->ident);
                 if (existing != NULL) {
-                    REPORTF_ERROR("redefinition of constant '%s'", stmt->ident);
+                    REPORTF_ERROR(
+                        "redefinition of identifier '%s'", stmt->ident);
                     reporter_print_loc(&rep, stmt->loc);
+                    const char* filename = rep.filename;
+                    if (existing->ty == IdentResolTy_Const) {
+                        filename = existing->src_filename;
+                    }
+                    REPORTF_INFO(
+                        "previous definition of '%s' here", existing->ident);
+                    reporter_print_loc(&rep, existing->loc);
+                    rep.filename = filename;
                     errors_occured = true;
                     pstmt_free(stmt);
                     continue;
@@ -134,6 +164,24 @@ int main(int argc, char** argv)
         ip += size;
     }
 
+    for (size_t i = 0; i < global_symbols_size; ++i) {
+        const IdentResol* res
+            = ident_resolver_resolve(&resolver, global_symbols[i].ident);
+        if (res == NULL) {
+            REPORTF_ERROR("undefined global '%s'", global_symbols[i].ident);
+            REPORTF_INFO("'%s' declared global here", global_symbols[i].ident);
+            reporter_print_loc(&rep, global_symbols[i].loc);
+            continue;
+        } else if (res->ty != IdentResolTy_Label) {
+            REPORTF_ERROR("'%s' cannot be declared global", res->ident);
+            reporter_print_loc(&rep, res->loc);
+            REPORTF_INFO("'%s' declared global here", global_symbols[i].ident);
+            reporter_print_loc(&rep, global_symbols[i].loc);
+            continue;
+        }
+        global_symbols[i].ip = res->ip;
+    }
+
     if (errors_occured) {
         fprintf(stderr, "nothing written. stopping...\n");
         res = -1;
@@ -188,6 +236,10 @@ leave_free_chunk:
     for (size_t i = 0; i < lines_size; ++i) {
         pline_free(lines[i]);
     }
+    for (size_t i = 0; i < global_symbols_size; ++i) {
+        free(global_symbols[i].ident);
+    }
+    free(global_symbols);
     free(lines);
     free(input_text);
     ident_resolver_destroy(&resolver);
@@ -270,8 +322,23 @@ static inline int include_file(IdentResolver* resolver,
                 const IdentResol* existing
                     = ident_resolver_resolve(resolver, stmt->ident);
                 if (existing != NULL) {
-                    REPORTF_ERROR("redefinition of constant '%s'", stmt->ident);
+                    if (existing->ty == IdentResolTy_Const
+                        && strcmp(existing->src_filename, filepath) == 0) {
+                        // Same file included multiple times.
+                        pstmt_free(stmt);
+                        continue;
+                    }
+                    REPORTF_ERROR(
+                        "redefinition of identifier '%s'", stmt->ident);
                     reporter_print_loc(&rep, stmt->loc);
+                    const char* filename = rep.filename;
+                    if (existing->ty == IdentResolTy_Const) {
+                        filename = existing->src_filename;
+                    }
+                    REPORTF_INFO(
+                        "previous definition of '%s' here", existing->ident);
+                    reporter_print_loc(&rep, existing->loc);
+                    rep.filename = filename;
                     errors_occured = true;
                     pstmt_free(stmt);
                     continue;
@@ -372,7 +439,7 @@ static inline void use_labels(IdentResolver* resolver, PLabel* label)
         return;
     use_labels(resolver, label->next);
     const IdentResol* existing = ident_resolver_resolve(resolver, label->ident);
-    if (existing->ty == IdentResolTy_Label) {
+    if (existing && existing->ty == IdentResolTy_Label) {
         resolver->current_parent = existing;
     }
 }

asm/report.c

@@ -4,6 +4,12 @@
 void print_report_loc(
     const char* filename, const char* text, size_t text_len, Loc loc)
 {
+    const char* displacement_spaces
+        = "                                                                "
+          "                                                                "
+          "                                                                "
+          "                                                                ";
+
     size_t line_start = loc.idx;
     while (line_start > 0 && text[line_start] != '\n') {
         line_start -= 1;
@@ -20,8 +26,8 @@ void print_report_loc(
 
     fprintf(stderr,
         "    \x1b[96m--> ./%s:%d:%d\n     "
-        "\x1b[37m|\n\x1b[96m%5d\x1b[37m|%.*s\n     "
+        "\x1b[37m|\n\x1b[96m%5d\x1b[37m|\x1b[0m%.*s\n     "
-        "|%*c\x1b[1;91m^\x1b[0m\n",
+        "\x1b[37m|%.*s\x1b[1;91m^\x1b[0m\n",
         filename,
         loc.line,
         loc.col,
@@ -29,7 +35,7 @@ void print_report_loc(
         line_len,
         line,
         loc.col - 1,
-        ' ');
+        displacement_spaces);
 }
 
 void reporter_print_loc(Reporter* rep, Loc loc)

kern/main.asm

@@ -1,6 +1,10 @@
 
 include "arch.asm"
 
+
+global start
+extern other
+
 start:
     ; rsp points *at* the top element
     mov rbp, 2048
@@ -15,6 +19,8 @@ start:
     mov r1, 1
     int Int_DiskRead
 
+    jmp other
+
 main_loop:
     hlt
     jmp main_loop