ground-rewrite/src/Bytecode/Instruction/execute.c

#include "../../../include/ground.h"
#include "../../linenoise/linenoise.h"
#include <stdint.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define HEAP_GET(heap, idx) (&(heap)->heap[(idx)])
#define HEAP_SET(heap, idx, val) ((heap)->heap[(idx)] = (val))

static void printValue(GroundBytecodeValue* val) {
    switch (val->type.type) {
        case GroundType_Int:
            printf("%" PRId64, val->as.Int);
            break;
        case GroundType_Double:
            printf("%f", val->as.Double);
            break;
        case GroundType_Bool:
            printf(val->as.Bool ? "true" : "false");
            break;
        case GroundType_Char:
            printf("%c", val->as.Char);
            break;
        case GroundType_String:
            printf("%s", val->as.String.cstr);
            break;
        default:
            printf("<fixme>");
            break;
    }
}

int64_t _GroundBytecodeInstructionExecute(GroundBytecodeInstruction* instruction, GroundBytecodeHeap* heap) {

    static const void* jumpTable[] = {
        &&IF, &&JUMP, &&END, 
        &&INPUT, &&PRINT, &&PRINTLN, 
        &&SET, &&GETTYPE, &&EXISTS, 
        &&SETLIST, &&SETLISTAT, &&GETLISTAT, &&GETLISTSIZE, &&LISTAPPEND,
        &&GETSTRSIZE, &&GETSTRCHARAT, 
        &&ADD, &&SUBTRACT, &&MULTIPLY, &&DIVIDE, 
        &&EQUAL, &&INEQUAL, &&NOT, &&GREATER, &&LESSER, 
        &&AND, &&OR, &&XOR, &&NEG, &&SHIFT, 
        &&STOI, &&STOD, &&ITOC, &&CTOI, &&TOSTRING, 
        &&FUN, &&RETURN, &&ENDFUN, &&CALL, &&CALLMETHOD, 
        &&STRUCT, &&ENDSTRUCT, &&INIT, &&GETFIELD, &&SETFIELD, 
        &&USE, &&EXTERN, &&CREATELABEL, 
        &&PAUSE, &&DROP, &&LICENSE, &&ERRORCMD, &&THROW, &&CATCH
    };

    goto *jumpTable[instruction->type];

    IF: {
        GroundBytecodeValue* cond = HEAP_GET(heap, instruction->args.at[0]);
        if (cond->as.Bool) {
            return instruction->args.at[1];
        }
        return -1;
    }
    JUMP: {
        return instruction->args.at[0];
    }
    END: {
        return -2;
    }
    INPUT: {
        char* input = linenoise("");
        HEAP_SET(heap, instruction->args.at[0], Ground.New.BytecodeValue(Ground.New.Value.String(Ground.New.String(input))));
        free(input);
        return -1;
    }
    PRINT: {
        for (GroundSize i = 0; i < instruction->args.len; i++) {
            printValue(HEAP_GET(heap, instruction->args.at[i]));
        }
        return -1;
    }
    PRINTLN: {
        for (GroundSize i = 0; i < instruction->args.len; i++) {
            printValue(HEAP_GET(heap, instruction->args.at[i]));
        }
        printf("\n");
        return -1;
    }
    SET: {
        HEAP_SET(heap, instruction->args.at[0], *HEAP_GET(heap, instruction->args.at[1]));
        return -1;
    }
    GETTYPE: {
        Ground.Log.Warning("GETTYPE is deprecated");
        return -1;
    }
    EXISTS: {
        Ground.Log.Warning("EXISTS is deprecated");
        return -1;
    }
    SETLIST: {
        return -1;
    }
    SETLISTAT: {
        return -1;
    }
    GETLISTAT: {
        return -1;
    }
    GETLISTSIZE: {
        return -1;
    }
    LISTAPPEND: {
        return -1;
    }
    GETSTRSIZE: {
        return -1;
    }
    GETSTRCHARAT: {
        return -1;
    }
    ADD: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);

        switch (left->type.type) {
            case GroundType_Int: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Int(left->as.Int + right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Int + right->as.Double));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid add operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
                break;
            }
            case GroundType_Double: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Double + right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Double + right->as.Double));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid add operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
                break;
            }
            case GroundType_String: {
                switch (right->type.type) {
                    case GroundType_String: {
                        GroundSize total = left->as.String.len + right->as.String.len;
                        char* buf = malloc(total + 1);
                        if (buf == NULL) {
                            Ground.Log.Error("malloc failed (instruction ADD{string, string, dirref}) in Ground.Instruction.execute()");
                            Ground.Flags.error = true;
                            break;
                        }
                        sprintf(buf, "%s%s", left->as.String.cstr, right->as.String.cstr);
                        *final = Ground.New.BytecodeValue(Ground.New.Value.String(Ground.New.String(buf)));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid add operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
            }
            default: {
                Ground.Log.Error("invalid add operation in Ground.Instruction.execute()");
                Ground.Flags.error = true;
                break;
            }
        }
        return -1;
    }
    SUBTRACT: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);

        switch (left->type.type) {
            case GroundType_Int: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Int(left->as.Int - right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Int - right->as.Double));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
                break;
            }
            case GroundType_Double: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Double - right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Double - right->as.Double));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
                break;
            }
            default: {
                Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                Ground.Flags.error = true;
                break;
            }
        }
        return -1;
    }
    MULTIPLY: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);

        switch (left->type.type) {
            case GroundType_Int: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Int(left->as.Int * right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Int * right->as.Double));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
                break;
            }
            case GroundType_Double: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Double * right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Double * right->as.Double));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
                break;
            }
            default: {
                Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                Ground.Flags.error = true;
                break;
            }
        }
        return -1;
    }
    DIVIDE: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);

        switch (left->type.type) {
            case GroundType_Int: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Int(left->as.Int / right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Int / right->as.Double));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
                break;
            }
            case GroundType_Double: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Double / right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(left->as.Double / right->as.Double));
                        break;
                    }
                    default: {
                        Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                        Ground.Flags.error = true;
                        break;
                    }
                }
                break;
            }
            default: {
                Ground.Log.Error("invalid subtract operation in Ground.Instruction.execute()");
                Ground.Flags.error = true;
                break;
            }
        }
        return -1;
    }
    EQUAL: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);

        switch (left->type.type) {
            case GroundType_Int: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Int == right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Int == right->as.Double));
                        break;
                    }
                    default: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                        break;
                    }
                }
                break;
            }
            case GroundType_Double: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Double == right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Double == right->as.Double));
                        break;
                    }
                    default: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                        break;
                    }
                }
                break;
            }
            case GroundType_Char: {
                if (right->type.type == GroundType_Char) {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Char == right->as.Char));
                } else {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                }
                break;
            }
            case GroundType_Bool: {
                if (right->type.type == GroundType_Bool) {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Bool == right->as.Bool));
                } else {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                }
                break;
            }
            case GroundType_String: {
                if (right->type.type == GroundType_String) {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(strcmp(left->as.String.cstr, right->as.String.cstr) == 0));
                } else {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                }
                break;
            }
            default: {
                *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                break;
            }
        }
        return -1;
    }
    INEQUAL: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);

        switch (left->type.type) {
            case GroundType_Int: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Int != right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Int != right->as.Double));
                        break;
                    }
                    default: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                        break;
                    }
                }
                break;
            }
            case GroundType_Double: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Double != right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Double != right->as.Double));
                        break;
                    }
                    default: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                        break;
                    }
                }
                break;
            }
            case GroundType_Char: {
                if (right->type.type == GroundType_Char) {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Char != right->as.Char));
                } else {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                }
                break;
            }
            case GroundType_Bool: {
                if (right->type.type == GroundType_Bool) {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Bool != right->as.Bool));
                } else {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                }
                break;
            }
            case GroundType_String: {
                if (right->type.type == GroundType_String) {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(strcmp(left->as.String.cstr, right->as.String.cstr) != 0));
                } else {
                    *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                }
                break;
            }
            default: {
                *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                break;
            }
        }
        return -1;
    }
    NOT: {
        HEAP_SET(heap, instruction->args.at[1], Ground.New.BytecodeValue(Ground.New.Value.Bool(!HEAP_GET(heap, instruction->args.at[0])->as.Bool)));
        return -1;
    }
    GREATER: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);

        switch (left->type.type) {
            case GroundType_Int: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Int > right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Int > right->as.Double));
                        break;
                    }
                    default: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                        break;
                    }
                }
                break;
            }
            case GroundType_Double: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Double > right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Double > right->as.Double));
                        break;
                    }
                    default: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                        break;
                    }
                }
                break;
            }
            default: {
                *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                break;
            }
        }
        return -1;
    }
    LESSER: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);

        switch (left->type.type) {
            case GroundType_Int: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Int < right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Int < right->as.Double));
                        break;
                    }
                    default: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                        break;
                    }
                }
                break;
            }
            case GroundType_Double: {
                switch (right->type.type) {
                    case GroundType_Int: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Double < right->as.Int));
                        break;
                    }
                    case GroundType_Double: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Double < right->as.Double));
                        break;
                    }
                    default: {
                        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(true));
                        break;
                    }
                }
                break;
            }
            default: {
                *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(false));
                break;
            }
        }
        return -1;
    }
    AND: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);
        
        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Bool && right->as.Bool));

        return -1;
    }
    OR: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);
        
        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Bool || right->as.Bool));

        return -1;
    }
    XOR: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[2]);
        GroundBytecodeValue* left = HEAP_GET(heap, instruction->args.at[0]);
        GroundBytecodeValue* right = HEAP_GET(heap, instruction->args.at[1]);
        
        *final = Ground.New.BytecodeValue(Ground.New.Value.Bool(left->as.Bool != right->as.Bool));

        return -1;
    }
    NEG: {
        return -1;
    }
    SHIFT: {
        return -1;
    }
    STOI: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[1]);
        GroundBytecodeValue* in = HEAP_GET(heap, instruction->args.at[0]);

        char* status = NULL;

        *final = Ground.New.BytecodeValue(Ground.New.Value.Int(strtoll(in->as.String.cstr, &status, 0)));

        if (status != in->as.String.cstr) {
            Ground.Flags.error = true;
            Ground.Log.Error("Failed converting string to double");
        }

        return -1;
    }
    STOD: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[1]);
        GroundBytecodeValue* in = HEAP_GET(heap, instruction->args.at[0]);

        char* status = NULL;

        *final = Ground.New.BytecodeValue(Ground.New.Value.Double(strtod(in->as.String.cstr, &status)));

        if (status != in->as.String.cstr) {
            Ground.Flags.error = true;
            Ground.Log.Error("Failed converting string to double");
        }

        return -1;
    }
    ITOC: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[1]);
        GroundBytecodeValue* in = HEAP_GET(heap, instruction->args.at[0]);
        
        *final = Ground.New.BytecodeValue(Ground.New.Value.Char((char)in->as.Int));

        return -1;
    }
    CTOI: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[1]);
        GroundBytecodeValue* in = HEAP_GET(heap, instruction->args.at[0]);
        
        *final = Ground.New.BytecodeValue(Ground.New.Value.Int((int64_t)in->as.Char));

        return -1;
    }
    TOSTRING: {
        GroundBytecodeValue* final = HEAP_GET(heap, instruction->args.at[1]);
        GroundBytecodeValue* in = HEAP_GET(heap, instruction->args.at[0]);

        char buf[4096];

        switch (in->type.type) {
            case GroundType_Int: {
                snprintf(buf, sizeof(buf), "%" PRId64, in->as.Int);
                break;
            }
            case GroundType_Double: {
                snprintf(buf, sizeof(buf), "%f", in->as.Double);
                break;
            }
            case GroundType_Char: {
                snprintf(buf, sizeof(buf), "%c", in->as.Char);
                break;
            }
            case GroundType_Bool: {
                snprintf(buf, sizeof(buf), in->as.Bool ? "true" : "false");
                break;
            }
            case GroundType_String: {
                *in = Ground.New.BytecodeValue(Ground.New.Value.String(final->as.String));
                return -1;
            }

            default: {
                // TODO: implement tostring for complex types
                snprintf(buf, sizeof(buf), "<FIXME>");
                break;
            }
        }

        *in = Ground.New.BytecodeValue(Ground.New.Value.String(Ground.New.String(buf)));
        
        return -1;
    }
    FUN: {
        // no-op
        return -1;
    }
    RETURN: {
        return -1;
    }
    ENDFUN: {
        // no-op
        return -1;
    }
    CALL: {
        return -1;
    }
    CALLMETHOD: {
        return -1;
    }
    STRUCT: {
        // no-op
        return -1;
    }
    ENDSTRUCT: {
        // no-op
        return -1;
    }
    INIT: {
        return -1;
    }
    GETFIELD: {
        return -1;
    }
    SETFIELD: {
        return -1;
    }
    USE: {
        return -1;
    }
    EXTERN: {
        return -1;
    }
    CREATELABEL: {
        // no-op
        return -1;
    }
    PAUSE: {
        return -1;
    }
    DROP: {
        GroundBytecodeValue* in = HEAP_GET(heap, instruction->args.at[0]);
        Ground.Free.BytecodeValue(in);
        *in = Ground.New.BytecodeValue(Ground.New.Value.Int(0));
        return -1;
    }
    LICENSE: {
        return -1;
    }
    ERRORCMD: {
        return -1;
    }
    THROW: {
        return -1;
    }
    CATCH: {
        return -1;
    }

    Ground.Log.Error("operation fell through in Ground.Instruction.execute()");
    Ground.Flags.error = true;

    return -1;
}