checkpoint

1 files changed, 109 insertions, 0 deletions

diff --git a/src/sim86/libs/reference_decoder/sim86_instruction.h b/src/sim86/libs/reference_decoder/sim86_instruction.h
new file mode 100644
index 0000000..191635a
--- /dev/null
+++ b/src/sim86/libs/reference_decoder/sim86_instruction.h
@@ -0,0 +1,109 @@
+/* ========================================================================
+
+   (C) Copyright 2023 by Molly Rocket, Inc., All Rights Reserved.
+   
+   This software is provided 'as-is', without any express or implied
+   warranty. In no event will the authors be held liable for any damages
+   arising from the use of this software.
+   
+   Please see https://computerenhance.com for more information
+   
+   ======================================================================== */
+
+typedef u32 register_index;
+
+// NOTE(casey): To make it easier to compile with languages which do not
+// have auto-typedef'ing (like C, etc.), all types are manually typedef'd here.
+typedef struct register_access register_access;
+typedef struct effective_address_term effective_address_term;
+typedef struct effective_address_expression effective_address_expression;
+typedef struct immediate immediate;
+typedef struct instruction_operand instruction_operand;
+typedef struct instruction instruction;
+
+typedef enum operation_type : u32
+{
+    Op_None,
+    
+#define INST(Mnemonic, ...) Op_##Mnemonic,
+#define INSTALT(...)
+#include "sim86_instruction_table.inl"
+    
+    Op_Count,
+} operation_type;
+
+enum instruction_flag
+{
+    Inst_Lock = 0x1,
+    Inst_Rep = 0x2,
+    Inst_Segment = 0x4,
+    Inst_Wide = 0x8,
+    Inst_Far = 0x10,
+    Inst_RepNE = 0x20, // NOTE(casey): For user convenience, this will be set _in addition to_ Inst_Rep for REPNE/REPNZ
+};
+
+struct register_access
+{
+    register_index Index;
+    u32 Offset;
+    u32 Count;
+};
+
+struct effective_address_term
+{
+    register_access Register;
+    s32 Scale;
+};
+
+enum effective_address_flag
+{
+    Address_ExplicitSegment = 0x1,
+};
+struct effective_address_expression
+{
+    effective_address_term Terms[2];
+    u32 ExplicitSegment;
+    s32 Displacement;
+    u32 Flags;
+};
+
+enum immediate_flag
+{
+    Immediate_RelativeJumpDisplacement = 0x1,
+};
+struct immediate
+{
+    s32 Value;
+    u32 Flags;
+};
+
+typedef enum operand_type : u32
+{
+    Operand_None,
+    Operand_Register,
+    Operand_Memory,
+    Operand_Immediate,
+} operand_type;
+struct instruction_operand
+{
+    operand_type Type;
+    union
+    {
+        effective_address_expression Address;
+        register_access Register;
+        immediate Immediate;
+    };
+};
+
+struct instruction
+{
+    u32 Address;
+    u32 Size;
+    
+    operation_type Op;
+    u32 Flags;
+    
+    instruction_operand Operands[2];
+    
+    register_index SegmentOverride;
+};