1 files changed, 93 insertions, 0 deletions
diff --git a/plugins/gme/game-music-emu-0.6.0/gme/Gb_Cpu.h b/plugins/gme/game-music-emu-0.6.0/gme/Gb_Cpu.h
new file mode 100644
index 00000000..9d623e04
--- /dev/null
+++ b/plugins/gme/game-music-emu-0.6.0/gme/Gb_Cpu.h
@@ -0,0 +1,93 @@
+// Nintendo Game Boy CPU emulator
+// Treats every instruction as taking 4 cycles
+
+// Game_Music_Emu 0.5.5
+#ifndef GB_CPU_H
+#define GB_CPU_H
+
+#include "blargg_common.h"
+#include "blargg_endian.h"
+
+typedef unsigned gb_addr_t; // 16-bit CPU address
+
+class Gb_Cpu {
+	enum { clocks_per_instr = 4 };
+public:
+	typedef BOOST::uint8_t uint8_t;
+	
+	// Clear registers and map all pages to unmapped
+	void reset( void* unmapped = 0 );
+	
+	// Map code memory (memory accessed via the program counter). Start and size
+	// must be multiple of page_size.
+	enum { page_size = 0x2000 };
+	void map_code( gb_addr_t start, unsigned size, void* code );
+	
+	uint8_t* get_code( gb_addr_t );
+	
+	// Push a byte on the stack
+	void push_byte( int );
+	
+	// Game Boy Z80 registers. *Not* kept updated during a call to run().
+	struct core_regs_t {
+	#if BLARGG_BIG_ENDIAN
+		uint8_t b, c, d, e, h, l, flags, a;
+	#else
+		uint8_t c, b, e, d, l, h, a, flags;
+	#endif
+	};
+	
+	struct registers_t : core_regs_t {
+		long pc; // more than 16 bits to allow overflow detection
+		BOOST::uint16_t sp;
+	};
+	registers_t r;
+	
+	// Interrupt enable flag set by EI and cleared by DI
+	//bool interrupts_enabled; // unused
+	
+	// Base address for RST vectors (normally 0)
+	gb_addr_t rst_base;
+	
+	// If CPU executes opcode 0xFF at this address, it treats as illegal instruction
+	enum { idle_addr = 0xF00D };
+	
+	// Run CPU for at least 'count' cycles and return false, or return true if
+	// illegal instruction is encountered.
+	bool run( blargg_long count );
+	
+	// Number of clock cycles remaining for most recent run() call
+	blargg_long remain() const { return state->remain * clocks_per_instr; }
+	
+	// Can read this many bytes past end of a page
+	enum { cpu_padding = 8 };
+	
+public:
+	Gb_Cpu() : rst_base( 0 ) { state = &state_; }
+	enum { page_shift = 13 };
+	enum { page_count = 0x10000 >> page_shift };
+private:
+	// noncopyable
+	Gb_Cpu( const Gb_Cpu& );
+	Gb_Cpu& operator = ( const Gb_Cpu& );
+	
+	struct state_t {
+		uint8_t* code_map [page_count + 1];
+		blargg_long remain;
+	};
+	state_t* state; // points to state_ or a local copy within run()
+	state_t state_;
+	
+	void set_code_page( int, uint8_t* );
+};
+
+inline BOOST::uint8_t* Gb_Cpu::get_code( gb_addr_t addr )
+{
+	return state->code_map [addr >> page_shift] + addr
+	#if !BLARGG_NONPORTABLE
+		% (unsigned) page_size
+	#endif
+	;
+}
+
+#endif