void expr_codegen(struct expr *e, FILE *file) {
int string_count = 0, found = 0, count = 1;
struct string_node *sn;
char* string_label = (char*)malloc(9);
char* label_name = (char*)malloc(9);
struct expr *temp_ptr;
if(!e) return;
switch(e->kind) {
case EXPR_LIST:
break;
case EXPR_ASSIGNMENT:
expr_codegen(e->right, file);
fprintf(file, "\tMOV %s, %s\t\t# Assignment\n", register_name(e->right->reg), symbol_code(e->left->symbol));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_OR:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tOR %s, %s\n", register_name(e->left->reg), register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_AND:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tAND %s, %s\n", register_name(e->left->reg), register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_LT:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tCMP %s, %s\t\t\n", register_name(e->left->reg), register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
sprintf(label_name, "done_%d", labelNum);
fprintf(file, "\tJG %s\n", label_name);
fprintf(file, "\tMOV $0, %s\n", register_name(e->right->reg));
fprintf(file, "%s:\n", label_name);
e->reg = e->right->reg;
register_free(e->left->reg);
labelNum++;
break;
case EXPR_GT:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tCMP %s, %s\t\t\n", register_name(e->left->reg), register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
sprintf(label_name, "done_%d", labelNum);
fprintf(file, "\tJL %s\n", label_name);
fprintf(file, "\tMOV $0, %s\n", register_name(e->right->reg));
fprintf(file, "%s:\n", label_name);
e->reg = e->right->reg;
register_free(e->left->reg);
labelNum++;
break;
case EXPR_LE:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tCMP %s, %s\t\t\n", register_name(e->left->reg), register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
sprintf(label_name, "done_%d", labelNum);
fprintf(file, "\tJGE %s\n", label_name);
fprintf(file, "\tMOV $0, %s\n", register_name(e->right->reg));
fprintf(file, "%s:\n", label_name);
e->reg = e->right->reg;
register_free(e->left->reg);
labelNum++;
break;
case EXPR_GE:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tCMP %s, %s\t\t\n", register_name(e->left->reg), register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
sprintf(label_name, "done_%d", labelNum);
fprintf(file, "\tJLE %s\n", label_name);
fprintf(file, "\tMOV $0, %s\n", register_name(e->right->reg));
fprintf(file, "%s:\n", label_name);
e->reg = e->right->reg;
register_free(e->left->reg);
labelNum++;
break;
case EXPR_NOT_EQUALS:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tCMP %s, %s\t\t\n", register_name(e->left->reg), register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
sprintf(label_name, "done_%d", labelNum);
fprintf(file, "\tJNE %s\n", label_name);
fprintf(file, "\tMOV $0, %s\n", register_name(e->right->reg));
fprintf(file, "%s:\n", label_name);
e->reg = e->right->reg;
register_free(e->left->reg);
labelNum++;
break;
case EXPR_EQUALS:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tCMP %s, %s\t\t\n", register_name(e->left->reg), register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV $1, %s\n", register_name(e->right->reg));
sprintf(label_name, "done_%d", labelNum);
fprintf(file, "\tJE %s\n", label_name);
fprintf(file, "\tMOV $0, %s\n", register_name(e->right->reg));
fprintf(file, "%s:\n", label_name);
e->reg = e->right->reg;
register_free(e->left->reg);
labelNum++;
break;
case EXPR_ADD:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tADD %s, %s\n", register_name(e->left->reg), register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_MINUS:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tSUB %s, %s\n", register_name(e->right->reg), register_name(e->left->reg));
e->reg = e->left->reg;
register_free(e->right->reg);
break;
case EXPR_TIMES:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tMOV %s, %rax\t\t#Move left value into rax to prepare for multiplying\n", register_name(e->left->reg));
fprintf(file, "\tIMUL %s\t\t# Multiply %rax by the value in %s\n", register_name(e->right->reg), register_name(e->right->reg));
fprintf(file, "\tMOV %rax, %s\t\t# Move multiplied result back to non-scratch register\n", register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_DIVIDES:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tMOVQ %s, %rax\t\t#Move left value into rax to prepare for dividing\n", register_name(e->left->reg));
fprintf(file, "\tCQTO\n");
fprintf(file, "\tIDIVQ %s\t\t\t# Divide %rax by the value in %s\n", register_name(e->right->reg), register_name(e->right->reg));
fprintf(file, "\tMOVQ %rax, %s\t\t# Move divided result back to non-scratch register\n", register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_MOD:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tMOVQ %s, %rax\t\t#Move left value into rax to prepare for dividing\n", register_name(e->left->reg));
fprintf(file, "\tCQTO\n");
fprintf(file, "\tIDIVQ %s\t\t\t# Divide %rax by the value in %s\n", register_name(e->right->reg), register_name(e->right->reg));
fprintf(file, "\tMOVQ %rdx, %s\t\t# Move remainder back to non-scratch register\n", register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_POWER:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\tMOV %s, %rdi\t\t# Move first argument for base of power\n", register_name(e->left->reg));
fprintf(file, "\tMOV %s, %rsi\t\t# Move second argument for exponent\n", register_name(e->right->reg));
fprintf(file, "\n\tPUSHQ %r10\n");
fprintf(file, "\tPUSHQ %r11\n");
fprintf(file, "\n\tCALL integer_power\n\n");
fprintf(file, "\tPOPQ %r11\n");
fprintf(file, "\tPOPQ %r10\n");
fprintf(file, "\tMOV %rax, %s\t\t# Move result of integer_power into register\n", register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_NEGATIVE:
expr_codegen(e->right, file);
fprintf(file, "\tNEG %s\t\t# Negate the value\n", register_name(e->right->reg));
e->reg = e->right->reg;
break;
case EXPR_NOT:
expr_codegen(e->right, file);
fprintf(file, "\tSUB $1, %s\t\t# Negate the boolean\n", register_name(e->right->reg));
e->reg = e->right->reg;
break;
case EXPR_PRE_INCREMENT:
expr_codegen(e->right, file);
fprintf(file, "\tINC %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV %s, %s\n", register_name(e->right->reg), symbol_code(e->right->symbol));
e->reg = e->right->reg;
break;
case EXPR_PRE_DECREMENT:
expr_codegen(e->right, file);
fprintf(file, "\tDEC %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV %s, %s\n", register_name(e->right->reg), symbol_code(e->right->symbol));
e->reg = e->right->reg;
break;
case EXPR_POST_INCREMENT:
// TODO: Delay incrementing
expr_codegen(e->left, file);
fprintf(file, "\tINC %s\n", register_name(e->left->reg));
fprintf(file, "\tMOV %s, %s\n", register_name(e->left->reg), symbol_code(e->left->symbol));
e->reg = e->left->reg;
break;
case EXPR_POST_DECREMENT:
expr_codegen(e->left, file);
fprintf(file, "\tDEC %s\n", register_name(e->left->reg));
fprintf(file, "\tMOV %s, %s\n", register_name(e->left->reg), symbol_code(e->left->symbol));
e->reg = e->left->reg;
break;
case EXPR_FUNCTION:
// setup function args
fprintf(file, "\tMOV $0, %rax\n");
temp_ptr = e->right;
while(temp_ptr) {
if(count > 6) {
printf("You may only supple 6 arguments to a function\n");
exit(1);
}
expr_codegen(temp_ptr->left, file);
fprintf(file, "\tMOV %s, %s\n", register_name(temp_ptr->left->reg), num_to_arg(count++));
temp_ptr = temp_ptr->right;
}
// call function
fprintf(file, "\n\tPUSH %r10\n");
fprintf(file, "\tPUSH %r11\n");
fprintf(file, "\n\tCALL %s\n\n", e->left->name);
fprintf(file, "\tPOP %r11\n");
fprintf(file, "\tPOP %r10\n");
e->reg = register_alloc();
fprintf(file, "\tMOV %rax, %s\n", register_name(e->reg));
break;
case EXPR_BOOLEAN:
e->reg = register_alloc();
fprintf(file, "\tMOV $%d, %s\n", e->literal_value, register_name(e->reg));
break;
case EXPR_INT:
e->reg = register_alloc();
fprintf(file, "\tMOV $%d, %s\n", e->literal_value, register_name(e->reg));
break;
case EXPR_CHAR:
e->reg = register_alloc();
fprintf(file, "\tMOV $%d, %s\n", e->literal_value, register_name(e->reg));
break;
case EXPR_STRING:
e->reg = register_alloc();
// find the string
sn = string_head;
while(sn) {
if(!strcmp(sn->text, e->string_literal)) {
// string found
found = 1;
sprintf(string_label, "LC%d", string_count);
e->reg = register_alloc();
fprintf(file, "\tMOV $%s, %s\t\t# Move string into register\n", string_label, register_name(e->reg));
break;
}
string_count++;
sn = sn->next;
}
if(!found) {
printf("Could not find string %s in data\n", e->string_literal);
exit(1);
}
break;
case EXPR_NAME:
e->reg = register_alloc();
fprintf(file, "\tMOV %s, %s\n", symbol_code(e->symbol), register_name(e->reg));
break;
case EXPR_ARRAY:
break;
case EXPR_ARRAY_LITERAL:
break;
}
}
//Generates code and writes it to a file
void expr_codegen(struct expr *e, FILE *file) {
if(!e) return;
struct expr *e2;
switch(e->kind) {
case EXPR_ASSIGNMENT:
fprintf(file, "\n\t#Assignment of %s %d right value\n", e->left->symbol->name, e->left->symbol->which);
expr_codegen(e->right, file);
fprintf(file, "\n\t#Assignment assign to %s %d\n", e->left->symbol->name, e->left->symbol->which);
fprintf(file, "\tMOV %s, %s\n", register_name(e->right->reg), symbol_code(e->left->symbol));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_GE: //all of these go to the compare function
case EXPR_LE:
case EXPR_GT:
case EXPR_LT:
case EXPR_EQ:
case EXPR_NE:
compare(e, file);
break;
case EXPR_ADD:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\n\t#Addition\n");
fprintf(file, "\tADD %s, %s\n", register_name(e->left->reg), register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_SUB:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\n\t#Subtraction\n");
fprintf(file, "\tSUB %s, %s\n", register_name(e->right->reg), register_name(e->left->reg));
e->reg = e->left->reg;
register_free(e->right->reg);
break;
case EXPR_MUL:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\n\t#Multiplication\n");
fprintf(file, "\tMOV %s, %%rax\n", register_name(e->left->reg));
fprintf(file, "\tIMUL %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV %%rax, %s\n", register_name(e->right->reg));
register_free(e->left->reg);
e->reg = e->right->reg;
break;
case EXPR_DIV:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\n\t#Division\n");
fprintf(file, "\tMOV %s, %%rax\n", register_name(e->left->reg));
fprintf(file, "\tCQO\n");
fprintf(file, "\tIDIV %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV %%rax, %s\n", register_name(e->right->reg));
register_free(e->left->reg);
e->reg = e->right->reg;
break;
case EXPR_MOD:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\n\t#Modulus\n");
fprintf(file, "\tMOV %s, %%rax\n", register_name(e->left->reg));
fprintf(file, "\tCQO\n");
fprintf(file, "\tIDIV %s\n", register_name(e->right->reg));
fprintf(file, "\tMOV %%rdx, %s\n", register_name(e->right->reg));
register_free(e->left->reg);
e->reg = e->right->reg;
break;
case EXPR_POW:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
int label_start = label_count++;
int label_end = label_count++;
fprintf(file, "\n\t#Exponent function\n");
fprintf(file, "\tMOV $1, %%rax\n");
fprintf(file, "L%d:\n", label_start);
fprintf(file, "\tCMP $0, %s\n", register_name(e->right->reg));
fprintf(file, "\tJE L%d\n", label_end);
fprintf(file, "\tSUB $1, %s\n", register_name(e->right->reg));
fprintf(file, "\tMUL %s\n", register_name(e->left->reg));
fprintf(file, "\tJMP L%d\n", label_start);
fprintf(file, "L%d:\n", label_end);
register_free(e->left->reg);
register_free(e->right->reg);
e->reg = register_alloc();
fprintf(file, "\tMOV %%rax, %s\n", register_name(e->reg));
break;
case EXPR_LOGICAL_NOT:
expr_codegen(e->right, file);
fprintf(file, "\n\t#Logical Not\n");
e->reg = e->right->reg;
fprintf(file, "\tCMPQ $0, %s\n", register_name(e->reg));
fprintf(file, "\tJNE L%d\n", label_count);
fprintf(file, "\tMOV $1, %s\n", register_name(e->reg));
fprintf(file, "\tJMP L%d\n", label_count+1);
fprintf(file, "L%d:\n", label_count++);
fprintf(file, "\tMOV $0, %s\n", register_name(e->reg));
fprintf(file, "L%d:\n", label_count++);
break;
case EXPR_LOGICAL_AND:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\n\t#Logical And\n");
fprintf(file, "\tAND %s, %s\n", register_name(e->left->reg), register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_LOGICAL_OR:
expr_codegen(e->left, file);
expr_codegen(e->right, file);
fprintf(file, "\n\t#Logical Or\n");
fprintf(file, "\tOR %s, %s\n", register_name(e->left->reg), register_name(e->right->reg));
e->reg = e->right->reg;
register_free(e->left->reg);
break;
case EXPR_POSTFIX_PLUS:
expr_codegen(e->left, file);
fprintf(file, "\n\t#Increment\n");
e->reg = register_alloc();
fprintf(file, "\tMOV %s, %s\n", register_name(e->left->reg), register_name(e->reg));
fprintf(file, "\tADD $1, %s\n", register_name(e->left->reg));
fprintf(file, "\tMOV %s, %s\n", register_name(e->left->reg), symbol_code(e->left->symbol));
register_free(e->left->reg);
break;
case EXPR_POSTFIX_MINUS:
expr_codegen(e->left, file);
fprintf(file, "\n\t#Increment\n");
e->reg = register_alloc();
fprintf(file, "\tMOV %s, %s\n", register_name(e->left->reg), register_name(e->reg));
fprintf(file, "\tSUB $1, %s\n", register_name(e->left->reg));
fprintf(file, "\tMOV %s, %s\n", register_name(e->left->reg), symbol_code(e->left->symbol));
register_free(e->left->reg);
break;
case EXPR_IDENT:
fprintf(file, "\n\t#Identifier %d %s\n", e->symbol->which, e->symbol->name);
e->reg = register_alloc();
if(e->symbol->type->kind == TYPE_STRING && e->symbol->kind == SCOPE_GLOBAL){
fprintf(file, "\tLEA %s, %s\n", symbol_code(e->symbol), register_name(e->reg));
} else {
fprintf(file, "\tMOV %s, %s\n", symbol_code(e->symbol), register_name(e->reg));
}
break;
case EXPR_INTEGER_LITERAL:
//comment label
fprintf(file, "\n\t#Integer literal %d\n", e->literal_value);
e->reg = register_alloc();
fprintf(file, "\tMOV $%d, %s\n", e->literal_value, register_name(e->reg));
break;
case EXPR_STRING_LITERAL:
//comment label
fprintf(file, "\n\t#String literal %s\n", e->string_literal);
e->reg = register_alloc();
fprintf(file, ".data\nSTR%d: \n.string \"%s\"\n.text\n", string_number, e->string_literal);
fprintf(file, "\tLEA STR%d, %s\n", string_number++, register_name(e->reg));
break;
case EXPR_CHAR_LITERAL:
fprintf(file, "\n\t#Char literal %c\n", e->literal_value);
e->reg = register_alloc();
fprintf(file, "\tMOV $%d, %s\n", e->literal_value, register_name(e->reg));
break;
case EXPR_TRUE:
fprintf(file, "\n\t#True\n");
e->reg = register_alloc();
fprintf(file, "\tMOV $%d, %s\n", e->literal_value, register_name(e->reg));
break;
case EXPR_FALSE:
fprintf(file, "\n\t#False\n");
e->reg = register_alloc();
fprintf(file, "\tMOV $%d, %s\n", e->literal_value, register_name(e->reg));
register_free(e->reg);
break;
case EXPR_FCALL:
if(function_params(e) >= 6) fcall_error();
e->reg = register_alloc();
fprintf(file, "\n\t#Calling function %s\n", e->left->name);
if(!e->right){
/* do nothing for no params */
} else if(e->right->kind != EXPR_COMMA){ //this means single argument
expr_codegen(e->right, file);
fprintf(file, "\n\t#Move Only Argument\n");
fprintf(file, "\tMOV %s, %%rdi\n", register_name(e->right->reg));
register_free(e->right->reg);
} else { //multiple parameters
struct expr *param = e->right;
int param_number = 0;
while(param->kind == EXPR_COMMA){
expr_codegen(param->left, file);
fprintf(file, "\n\t#Move Argument %d\n", param_number);
fprintf(file, "\tMOV %s, ", register_name(param->left->reg));
register_free(param->left->reg);
switch(param_number++){
case 0: fprintf(file, "%%rdi"); break;
case 1: fprintf(file, "%%rsi"); break;
case 2: fprintf(file, "%%rdx"); break;
case 3: fprintf(file, "%%rcx"); break;
case 4: fprintf(file, "%%r8"); break;
case 5: fprintf(file, "%%r9"); break;
}
fprintf(file, "\n");
param = param->right;
}
expr_codegen(param, file);
fprintf(file, "\n\t#Move Argument %d\n", param_number);
fprintf(file, "\tMOV %s, ", register_name(param->reg));
switch(param_number++){
case 0: fprintf(file, "%%rdi"); break;
case 1: fprintf(file, "%%rsi"); break;
case 2: fprintf(file, "%%rdx"); break;
case 3: fprintf(file, "%%rcx"); break;
case 4: fprintf(file, "%%r8"); break;
case 5: fprintf(file, "%%r9"); break;
}
fprintf(file, "\n");
register_free(param->reg);
}
fprintf(file, "\tPUSH %%r10\n");
fprintf(file, "\tPUSH %%r11\n");
fprintf(file, "\n\tCALL %s\n\n", e->left->name);
fprintf(file, "\tPOP %%r11\n");
fprintf(file, "\tPOP %%r10\n");
fprintf(file, "\tMOV %%rax, %s\n", register_name(e->reg));
break;
case EXPR_PARENS:
expr_codegen(e->right, file);
e->reg = e->right->reg;
break;
case EXPR_ARRCALL: //These 4 have to do with arrays
case EXPR_ARRINDEX: //We are not implementing arrays for codegen
case EXPR_BLOCK:
case EXPR_BLOCK_COMMA:
array_error();
break;
}
}
