1 files changed, 187 insertions, 0 deletions
diff --git a/lib/inst.h b/lib/inst.h
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+++ b/lib/inst.h
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+/* Copyright (C) 2023 Aryadev Chavali
+
+ * You may distribute and modify this code under the terms of the
+ * GPLv2 license.  You should have received a copy of the GPLv2
+ * license with this file.  If not, please write to:
+ * aryadev@aryadevchavali.com.
+
+ * Created: 2023-10-15
+ * Author: Aryadev Chavali
+ * Description: Instructions and opcodes
+ */
+
+#ifndef INST_H
+#define INST_H
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <lib/base.h>
+#include <lib/darr.h>
+
+typedef enum
+{
+  OP_NOOP = 0,
+
+  // Dealing with data and registers
+  OP_PUSH_BYTE,
+  OP_PUSH_HWORD,
+  OP_PUSH_WORD,
+
+  OP_POP_BYTE,
+  OP_POP_HWORD,
+  OP_POP_WORD,
+
+  OP_PUSH_REGISTER_BYTE,
+  OP_PUSH_REGISTER_HWORD,
+  OP_PUSH_REGISTER_WORD,
+
+  OP_MOV_BYTE,
+  OP_MOV_HWORD,
+  OP_MOV_WORD,
+
+  OP_DUP_BYTE,
+  OP_DUP_HWORD,
+  OP_DUP_WORD,
+
+  // Boolean operations
+  OP_NOT_BYTE,
+  OP_NOT_HWORD,
+  OP_NOT_WORD,
+
+  OP_OR_BYTE,
+  OP_OR_HWORD,
+  OP_OR_WORD,
+
+  OP_AND_BYTE,
+  OP_AND_HWORD,
+  OP_AND_WORD,
+
+  OP_XOR_BYTE,
+  OP_XOR_HWORD,
+  OP_XOR_WORD,
+
+  OP_EQ_BYTE,
+  OP_EQ_CHAR,
+  OP_EQ_HWORD,
+  OP_EQ_INT,
+  OP_EQ_LONG,
+  OP_EQ_WORD,
+
+  // Mathematical operations
+  OP_LT_BYTE,
+  OP_LT_CHAR,
+  OP_LT_HWORD,
+  OP_LT_INT,
+  OP_LT_LONG,
+  OP_LT_WORD,
+  OP_LTE_BYTE,
+  OP_LTE_CHAR,
+  OP_LTE_HWORD,
+  OP_LTE_INT,
+  OP_LTE_LONG,
+  OP_LTE_WORD,
+  OP_GT_BYTE,
+  OP_GT_CHAR,
+  OP_GT_HWORD,
+  OP_GT_INT,
+  OP_GT_LONG,
+  OP_GT_WORD,
+  OP_GTE_BYTE,
+  OP_GTE_CHAR,
+  OP_GTE_HWORD,
+  OP_GTE_INT,
+  OP_GTE_LONG,
+  OP_GTE_WORD,
+  OP_PLUS_BYTE,
+  OP_PLUS_HWORD,
+  OP_PLUS_WORD,
+
+  // Simple I/O
+  OP_PRINT_BYTE,
+  OP_PRINT_CHAR,
+  OP_PRINT_INT,
+  OP_PRINT_HWORD,
+  OP_PRINT_LONG,
+  OP_PRINT_WORD,
+
+  // Program control flow
+  OP_JUMP_ABS,
+  OP_JUMP_STACK,
+  OP_JUMP_REGISTER,
+  OP_JUMP_IF_BYTE,
+  OP_JUMP_IF_HWORD,
+  OP_JUMP_IF_WORD,
+
+  // Should not be an opcode
+  NUMBER_OF_OPCODES,
+  OP_HALT = 0b11111111, // top of the byte is a HALT
+} opcode_t;
+
+const char *opcode_as_cstr(opcode_t);
+
+#define OPCODE_IS_TYPE(OPCODE, OP_TYPE) \
+  (((OPCODE) >= OP_TYPE##_BYTE) && ((OPCODE) <= OP_TYPE##_WORD))
+
+#define OPCODE_DATA_TYPE(OPCODE, OP_TYPE)            \
+  ((OPCODE) == OP_TYPE##_BYTE      ? DATA_TYPE_BYTE  \
+   : ((OPCODE) == OP_TYPE##_HWORD) ? DATA_TYPE_HWORD \
+                                   : DATA_TYPE_WORD)
+
+typedef struct
+{
+  opcode_t opcode;
+  data_t operand;
+} inst_t;
+
+void inst_print(inst_t, FILE *);
+
+size_t inst_bytecode_size(inst_t);
+void inst_write_bytecode(inst_t, darr_t *);
+void insts_write_bytecode(inst_t *, size_t, darr_t *);
+// Here the dynamic array is a preloaded buffer of bytes, where
+// darr.available is the number of overall bytes and used is the
+// cursor (where we are in the buffer).
+inst_t inst_read_bytecode(darr_t *);
+inst_t *insts_read_bytecode(darr_t *, size_t *);
+
+void insts_write_bytecode_file(inst_t *, size_t, FILE *);
+inst_t *insts_read_bytecode_file(FILE *, size_t *);
+
+#define INST_NOOP ((inst_t){0})
+#define INST_HALT ((inst_t){.opcode = OP_HALT})
+
+#define INST_PUSH(TYPE, OP) \
+  ((inst_t){.opcode = OP_PUSH_##TYPE, .operand = D##TYPE(OP)})
+
+#define INST_MOV(TYPE, OP) \
+  ((inst_t){.opcode = OP_MOV_##TYPE, .operand = D##TYPE(OP)})
+
+#define INST_POP(TYPE) ((inst_t){.opcode = OP_POP_##TYPE})
+
+#define INST_PUSH_REG(TYPE, REG) \
+  ((inst_t){.opcode = OP_PUSH_REGISTER_##TYPE, .operand = D##TYPE(REG)})
+
+#define INST_DUP(TYPE, OP) \
+  ((inst_t){.opcode = OP_DUP_##TYPE, .operand = DWORD(OP)})
+
+#define INST_NOT(TYPE)  ((inst_t){.opcode = OP_NOT_##TYPE})
+#define INST_OR(TYPE)   ((inst_t){.opcode = OP_OR_##TYPE})
+#define INST_AND(TYPE)  ((inst_t){.opcode = OP_AND_##TYPE})
+#define INST_XOR(TYPE)  ((inst_t){.opcode = OP_XOR_##TYPE})
+#define INST_EQ(TYPE)   ((inst_t){.opcode = OP_EQ_##TYPE})
+#define INST_LT(TYPE)   ((inst_t){.opcode = OP_LT_##TYPE})
+#define INST_LTE(TYPE)  ((inst_t){.opcode = OP_LTE_##TYPE})
+#define INST_GT(TYPE)   ((inst_t){.opcode = OP_GT_##TYPE})
+#define INST_GTE(TYPE)  ((inst_t){.opcode = OP_GTE_##TYPE})
+#define INST_PLUS(TYPE) ((inst_t){.opcode = OP_PLUS_##TYPE})
+
+#define INST_JUMP_ABS(OP) \
+  ((inst_t){.opcode = OP_JUMP_ABS, .operand = DWORD(OP)})
+#define INST_JUMP_STACK    ((inst_t){.opcode = OP_JUMP_STACK})
+#define INST_JUMP_REGISTER ((inst_t){.opcode = OP_JUMP_REGISTER})
+#define INST_JUMP_IF(TYPE, OP) \
+  ((inst_t){.opcode = OP_JUMP_IF_##TYPE, .operand = DWORD(OP)})
+
+#define INST_PRINT(TYPE) ((inst_t){.opcode = OP_PRINT_##TYPE})
+#endif