.bss section management (globals)

4 files changed, 46 insertions, 30 deletions

diff --git a/src/generator.c b/src/generator.c
index 8329aee..c038b7f 100644
--- a/src/generator.c
+++ b/src/generator.c
@@ -14,27 +14,30 @@ void gen_prologue() {
   fprintf(output, "format_int db \"%%d\",10,0\n\n");
   fprintf(output, "section .bss\n");
 }
-void gen_prologue_continue(){
-  fprintf(output, "globals: resq %d\n", nb_globals);
-  fprintf(output, "section .text\n\nglobal _start\n");
-  fprintf(output, "print: ;print needs an argument in rax\n");
-  fprintf(output, "push rbp\n");
-  fprintf(output, "mov rbp, rsp\n");
-  fprintf(output, "push rsi\n");
-  fprintf(output, "mov rsi, rax\n");
-  fprintf(output, "mov rdi, format_int\n");
-  fprintf(output, "mov rax, 0\n");
-  fprintf(output, "call printf WRT ..plt\n");
-  fprintf(output, "pop rsi\n");
-  fprintf(output, "pop rbp\n");
-  fprintf(output, "ret\n");
-  fprintf(output, "\n_start:\n");
-  fprintf(output, "push rbp\nmov rbp, rsp\n\n");
+void gen_prologue_continue(int *bss_done){
+  if (*bss_done == 0){
+    fprintf(output, "globals: resq %d\n", nb_globals);
+    fprintf(output, "section .text\n\nglobal _start\n");
+    fprintf(output, "print: ;print needs an argument in rax\n");
+    fprintf(output, "push rbp\n");
+    fprintf(output, "mov rbp, rsp\n");
+    fprintf(output, "push rsi\n");
+    fprintf(output, "mov rsi, rax\n");
+    fprintf(output, "mov rdi, format_int\n");
+    fprintf(output, "mov rax, 0\n");
+    fprintf(output, "call printf WRT ..plt\n");
+    fprintf(output, "pop rsi\n");
+    fprintf(output, "pop rbp\n");
+    fprintf(output, "ret\n");
+    fprintf(output, "\n_start:\n");
+    fprintf(output, "push rbp\nmov rbp, rsp\n\n");
+    *bss_done = 1;
+  }
 }
 void gen_const_declaration() {
   fprintf(output, "mov rax,60 \n");
   fprintf(output, "mov rdi,0 \n");
-  fprintf(output, "syscall \n");
+  fprintf(output, "syscall \n\n");
   fprintf(output, ";global table\n");
   glo_display_table();
   fprintf(output, ";local table\n");
@@ -100,15 +103,20 @@ void gen_ifelse_end(int idx) {
 // ----- OPERATORS -----
 
 int gen_assign(const char ident[], Scope scope) {
-  const char instr_fmt[] = "pop QWORD [rbp - %d] ;%s\n";
-
+  int g_addr = glo_get_addr(ident);
   switch (scope) {
   case GLOBAL:
-    fprintf(output, instr_fmt, glo_get_addr(ident), ident);
+    fprintf(output, "pop QWORD [globals + %d] ;%s\n", glo_get_addr(ident), ident);
     return glo_lookup(ident);
   case LOCAL:
-    fprintf(output, instr_fmt, loc_get_addr(ident), ident);
-    return loc_lookup(ident);
+    if (g_addr == -1) {
+      fprintf(output, "pop QWORD [rbp - %d] ;%s\n", loc_get_addr(ident), ident);
+      return loc_lookup(ident);
+    }
+    else {
+      fprintf(output, "pop QWORD [globals + %d] ;%s\n", g_addr, ident);
+      return glo_lookup(ident);
+    } 
   default:
     exit(1);
   }
@@ -241,13 +249,20 @@ int gen_negate_expr(int type) {
 }
 
 int gen_value(const char ident[], Scope scope) {
+  int g_addr = glo_get_addr(ident);
   switch (scope) {
   case GLOBAL:
-    fprintf(output, "push QWORD [rbp - %d] ;%s\n", glo_get_addr(ident), ident);
+    fprintf(output, "push QWORD [globals + %d] ;%s\n", glo_get_addr(ident), ident);
     return glo_lookup(ident);
   case LOCAL:
-    fprintf(output, "push QWORD [rbp - %d] ;%s\n", loc_get_addr(ident), ident);
-    return loc_lookup(ident);
+    if (g_addr == -1) {
+      fprintf(output, "push QWORD [rbp - %d] ;%s\n", loc_get_addr(ident), ident);
+      return loc_lookup(ident);
+    }
+    else {
+      fprintf(output, "push QWORD [globals + %d] ;%s\n", g_addr, ident);
+      return glo_lookup(ident);
+    } 
   default:
     exit(1);
   }
diff --git a/src/generator.h b/src/generator.h
index 825ec8c..1a4c96a 100644
--- a/src/generator.h
+++ b/src/generator.h
@@ -17,7 +17,7 @@ extern int nb_globals;
 FILE *output;
 
 void gen_prologue();
-void gen_prologue_continue();
+void gen_prologue_continue(int *bss_done);
 void gen_const_declaration();
 void gen_declaration(const char name[], int type, Scope scope);
 
diff --git a/src/symbol_table.c b/src/symbol_table.c
index 8e6db97..6dc3e64 100644
--- a/src/symbol_table.c
+++ b/src/symbol_table.c
@@ -47,7 +47,6 @@ int glo_lookup(const char name[]) {
 
 int glo_get_addr(const char name[]) {
   int count;
-
   for (count = 0; count < glo_symbol_table.size; count++) {
     if (!strcmp(glo_symbol_table.entries[count].name, name)) {
       return glo_symbol_table.entries[count].addr;
diff --git a/src/tpc.y b/src/tpc.y
index b5ab84c..2938094 100644
--- a/src/tpc.y
+++ b/src/tpc.y
@@ -21,6 +21,7 @@ extern int lineno;
 int yylex();
 void yyerror(char *);
 static Scope scope = GLOBAL;
+static int bss_done = 0;
 static int num_label = 0;
 static int num_if = 0;
 %}
@@ -91,10 +92,11 @@ DeclFonct:
   Corps       { scope = GLOBAL; }
 ;
 EnTeteFonct:
-  TYPE IDENT Prologue '(' Parametres ')'
-| VOID IDENT Prologue '(' Parametres ')'
+  TYPE IDENT PrologueCont '(' Parametres ')'
+| VOID IDENT PrologueCont '(' Parametres ')'
 ;
-Prologue: {gen_prologue_continue();};
+
+PrologueCont: {gen_prologue_continue(&bss_done);};
 
 Parametres:
   VOID