add string literals via the data segment

1 files changed, 23 insertions, 11 deletions

diff --git a/codegen.c b/codegen.c
index 3d96d33..d9b2962 100644
--- a/codegen.c
+++ b/codegen.c
@@ -2,6 +2,7 @@
 #include "codegen.h"
 #include "scope.h"
 #include "register.h"
+#include "dseg.h"
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -27,6 +28,7 @@ static struct reg* MULDIV_OVERFLOW_REG = &RDX;
 #define FULL_REG_SZ 8
 #define WORD_SZ 2
 
+static struct dseg dseg;
 static struct scope* scope;
 static const struct fn_decl_node* active_fn;
 static integral_t branch_counter = 0;
@@ -95,7 +97,7 @@ static struct lval_def allocate_stack(
     const struct type* type
 ) {
     integral_t type_sz = get_effective_data_type(type)->sz;
-    fprintf(outfile, "\tsub rsp, %llu\n", type_sz);
+    fprintf(outfile, "\tsub rsp, 0x%llx\n", type_sz);
     scope->bp_offset += type_sz;
     return (struct lval_def) {
         .loc = {
@@ -156,14 +158,14 @@ static void emit_storage_loc(
             break;
         case STO_STACK:
             if (loc->bp_offset < 0)
-                fprintf(outfile, "[rbp + %lld]", -loc->bp_offset);
+                fprintf(outfile, "[rbp + 0x%llx]", -loc->bp_offset);
             else if (loc->bp_offset > 0)
-                fprintf(outfile, "[rbp - %lld]", loc->bp_offset);
+                fprintf(outfile, "[rbp - 0x%llx]", loc->bp_offset);
             else
                 fprintf(outfile, "[rbp]");
             break;
         case STO_IMM:
-            fprintf(outfile, "%llu", loc->value);
+            fprintf(outfile, "0x%llx", loc->value);
             break;
         case STO_UNRESOLVED:
             CGEN_PANIC("can't emit unresolved storage location");
@@ -346,7 +348,14 @@ static void emit_str_lit(
     const struct lval_def* dst
 ) {
     if (dst != NULL) {
-        CGEN_PANIC("string literals are not implemented");
+        const char* dseg_sym = dseg_put(&dseg, (struct dseg_entry) {
+            .type = ENT_STRING,
+            .key.string = node->val,
+        });
+        emit_mov(outfile, dst, &(struct storage_location) {
+            .type = STO_LABEL,
+            .label = dseg_sym,
+        });
     }
 }
 
@@ -370,10 +379,7 @@ static void emit_decl(
         allocate_stack(outfile, node->def_ref->type);
     node->def_ref->loc = var_dst.loc;
 
-    fprintf(outfile, "\t; %s", node->def_ref->name);
-    integral_t dst_sz = get_effective_data_type(var_dst.type)->sz;
-    emit_storage_loc(outfile, &var_dst.loc, dst_sz);
-    fprintf(outfile, "\n");
+    fprintf(outfile, "\t; %s\n", node->def_ref->name);
 
     if (node->initial_value != NULL)
         emit_expr(outfile, node->initial_value, &var_dst);
@@ -833,8 +839,8 @@ void emit_code(struct ast* ast, const char* path) {
     FILE* outfile = fopen(path, "w");
     if (outfile == NULL) CCC_PANIC;
 
+    dseg_init(&dseg);
     scope = ast->root_scope;
-    fprintf(outfile, "section .text\n");
 
     /* output all function declarations in the root scope as globals */
     const struct root_node* node = ast->root_node;
@@ -844,7 +850,8 @@ void emit_code(struct ast* ast, const char* path) {
     }
     fprintf(outfile, "\n");
 
-    /* actual code body */
+    /* text (code) segment */
+    fprintf(outfile, "section .text\n");
     node = ast->root_node;
     while (node != NULL) {
         emit_root_node(outfile, node);
@@ -852,5 +859,10 @@ void emit_code(struct ast* ast, const char* path) {
         node = node->next;
     }
 
+    /* data segment */
+    fprintf(outfile, "\n");
+    emit_dseg(outfile, &dseg);
+
+    dseg_destroy(&dseg);
     fclose(outfile);
 }