1. SASM Instructions¶

File: sasm_instructions.h
Author: Soham Metha
Date: January 2025

1.1. Table of Contents¶

• 1. SASM Instructions
  • 1.1. Table of Contents
  • 1.2. Opcode Enumeration
  • 1.3. Data Structures
    • 1.3.1. Instruction Structure
    • 1.3.2. Program Structure
  • 1.4. Function Declarations
    • 1.4.1. Stack Operations
    • 1.4.2. Instruction Execution
    • 1.4.3. Opcode Conversion

1.2. Opcode Enumeration¶

The Opcode enum defines all supported instructions in SASM.

1.3. Data Structures¶

1.3.1. Instruction Structure¶

Represents a single SASM instruction, consisting of an opcode and an operand.

typedef struct {
    Opcode type;  /**< The opcode of the instruction */
    Word operand; /**< The operand of the instruction */
} Instruction;

1.3.2. Program Structure¶

Represents a complete SASM program, including instructions and metadata.

typedef struct {
    Instruction instructions[PROGRAM_CAPACITY]; /**< Array of instructions */
    Word instruction_count;                     /**< Number of instructions */
    Word instruction_size;                      /**< Size of each instruction in bytes */
} Program;

1.4. Function Declarations¶

1.4.1. Stack Operations¶

1. Push to Stack

   Error __psh(Registers* r, Memory* mem, const Word* operand);
   

   Pushes a value onto the stack.

2. Equality Operation

   Error __eql(Registers* r, Memory* mem);
   

   Compares the top two values of the stack for equality.

3. Pop from Stack

   Error __pop(Registers* r, Memory* mem);
   

   Pops a value from the stack.

4. Duplicate Value

   Error __dup(Registers* r, Memory* mem, const Word* operand);
   

   Duplicates a value on the stack based on the operand.

1.4.2. Instruction Execution¶

• Execute an Instruction

  Error executeInst(const Program* prog, Memory* mem, CPU* cpu);
  

  Executes a single instruction in the virtual machine.

1.4.3. Opcode Conversion¶

1. Convert Opcode to String

   String opcodeAsStr(const Opcode* type);
   

   Converts an opcode to its string representation.

2. Convert String to Opcode

   Opcode strAsOpcode(const String* s);
   

   Converts a string to its corresponding opcode.