cground/src/compiler.c

#include "compiler.h"
#include "interpreter.h"
#include "types.h"
#include "include/estr.h"
#include <stdint.h>
#include <inttypes.h>

VariableTable createVariableTable() {
    VariableTable vt;
    vt.capacity = 16;
    vt.count = 0;
    vt.vars = malloc(sizeof(VariableInfo) * vt.capacity);
    return vt;
} 

void addVtVariable(VariableTable* vt, const char* name) {
    // check if it already exists
    for (size_t i = 0; i < vt->count; i++) {
        if (strcmp(vt->vars[i].name, name) == 0) {
            return;
        }
    }

    // increase capacity
    if (vt->count >= vt->capacity) {
        vt->capacity *= 2;
        vt->vars = realloc(vt->vars, sizeof(VariableInfo) * vt->capacity);
    }

    // add the variable
    strcpy(vt->vars[vt->count].name, name);
    vt->vars[vt->count].offset = vt->count * 8;
    vt->count++;
}

int getVariablePos(VariableTable* vt, const char* name) {
    for (size_t i = 0; i < vt->count; i++) {
        if (strcmp(vt->vars[i].name, name) == 0) {
            return vt->vars[i].offset;
        }
    }
    return -1;
}

char* processValueString(GroundArg arg) {
    if (arg.type == VALREF) {
        char* buf = malloc(sizeof(char) * 260);
        snprintf(buf, sizeof(char) * 260, "[%s]", arg.value.refName);
        return buf;
    }
    if (arg.type == VALUE) {
        if (arg.value.value.type != INT) {
            printf("Only int is supported right now");
            exit(1);
        }
        char* buf = malloc(sizeof(char) * 64);
        snprintf(buf, sizeof(char) * 260, "%" PRId64, arg.value.value.data.intVal);
        return buf;
    }
    return NULL;
}

char* compileGroundProgram(GroundProgram* program) {
    Estr start = CREATE_ESTR("global _start\nsection .text\n_start:\n");
    Estr data = CREATE_ESTR("section .bss\n");

    VariableTable varTable = createVariableTable();

    // Allocate a spot for all direct references
    for (size_t i = 0; i < program->size; i++) {
        GroundInstruction gi = program->instructions[i];
        for (size_t j = 0; j < gi.args.length; j++) {
            if (gi.args.args[j].type == DIRREF) {
                addVtVariable(&varTable, gi.args.args[j].value.refName);
            }
        }
    }

    // Create data section
    for (size_t i = 0; i < program->size; i++) {
        if (strcmp(varTable.vars[i].name, "") == 0) {
            continue;
        }
        APPEND_ESTR(data, "  ");
        APPEND_ESTR(data, varTable.vars[i].name);
        APPEND_ESTR(data, " resq 1\n");
    }

    // Generate assembly
    for (size_t i = 0; i < program->size; i++) {
        GroundInstruction gi = program->instructions[i];
        switch (gi.type) {
            case SET: {
                if (gi.args.length < 2) {
                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args", &gi, i);
                }
                if (gi.args.length > 2) {
                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args", &gi, i);
                }
                if (gi.args.args[0].type != DIRREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 1", &gi, i);
                }
                if (gi.args.args[1].type != VALUE) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a Value for arg 2", &gi, i);
                }

                char* varName= gi.args.args[0].value.refName;

                APPEND_ESTR(start, "  ; set\n")
                APPEND_ESTR(start, "  mov rax, ");
                APPEND_ESTR(start, processValueString(gi.args.args[1]));
                APPEND_ESTR(start, "\n");
                APPEND_ESTR(start, "  mov [");
                APPEND_ESTR(start, varName);
                APPEND_ESTR(start, "], rax\n");

                break;
            }
            case ADD: {
                if (gi.args.length < 3) {
                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for add instruction", &gi, i);
                }
                if (gi.args.length > 3) {
                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for add instruction", &gi, i);
                }
                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
                }
                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
                }
                if (gi.args.args[2].type != DIRREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
                }

                char* varName= gi.args.args[2].value.refName;
                APPEND_ESTR(start, "  ; add\n");
                APPEND_ESTR(start, "  mov rax, ");
                APPEND_ESTR(start, processValueString(gi.args.args[0]));
                APPEND_ESTR(start, "\n");
                APPEND_ESTR(start, "  add rax, ");
                APPEND_ESTR(start, processValueString(gi.args.args[1]));
                APPEND_ESTR(start, "\n");
                APPEND_ESTR(start, "  mov [");
                APPEND_ESTR(start, varName);
                APPEND_ESTR(start, "], rax\n");
                break;
            }
            case SUBTRACT: {
                if (gi.args.length < 3) {
                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for subtract instruction", &gi, i);
                }
                if (gi.args.length > 3) {
                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for subtract instruction", &gi, i);
                }
                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
                }
                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
                }
                if (gi.args.args[2].type != DIRREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
                }

                char* varName= gi.args.args[2].value.refName;
                APPEND_ESTR(start, "  ; subtract\n");
                APPEND_ESTR(start, "  mov rax, ");
                APPEND_ESTR(start, processValueString(gi.args.args[0]));
                APPEND_ESTR(start, "\n");
                APPEND_ESTR(start, "  sub rax, ");
                APPEND_ESTR(start, processValueString(gi.args.args[1]));
                APPEND_ESTR(start, "\n");
                APPEND_ESTR(start, "  mov [");
                APPEND_ESTR(start, varName);
                APPEND_ESTR(start, "], rax\n");
                break;
            }
            case MULTIPLY: {
                if (gi.args.length < 3) {
                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for multiply instruction", &gi, i);
                }
                if (gi.args.length > 3) {
                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for multiply instruction", &gi, i);
                }
                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
                }
                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
                }
                if (gi.args.args[2].type != DIRREF) {
                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
                }

                char* varName= gi.args.args[2].value.refName;
                APPEND_ESTR(start, "  ; add\n");
                APPEND_ESTR(start, "  mov rax, ");
                APPEND_ESTR(start, processValueString(gi.args.args[0]));
                APPEND_ESTR(start, "\n");
                APPEND_ESTR(start, "  imul rax, ");
                APPEND_ESTR(start, processValueString(gi.args.args[1]));
                APPEND_ESTR(start, "\n");
                APPEND_ESTR(start, "  mov [");
                APPEND_ESTR(start, varName);
                APPEND_ESTR(start, "], rax\n");
                break;
            }
            case END: {
                if (gi.args.length < 1) {
                    runtimeError(TOO_FEW_ARGS, "Expecting 1 arg for end instruction", &gi, i);
                }
                if (gi.args.length > 1) {
                    runtimeError(TOO_MANY_ARGS, "Expecting 1 arg for end instruction", &gi, i);
                }
                APPEND_ESTR(start, "  ; end\n");
                APPEND_ESTR(start, "  mov rax, 60\n");
                APPEND_ESTR(start, "  mov rdi, ");
                APPEND_ESTR(start, processValueString(gi.args.args[0]));
                APPEND_ESTR(start, "\n");
                APPEND_ESTR(start, "  syscall\n");
                break;
            }
            default: {
                printf("no\n");
                exit(1);
            }
        }
    }

    Estr complete = CREATE_ESTR("");
    APPEND_ESTR(complete, start.str);
    APPEND_ESTR(complete, "  ; End of program\n  mov rax, 60\n  mov rdi, 0\n  syscall\n");
    APPEND_ESTR(complete, data.str)

    return complete.str;
}