transform to switch case for ppu_tick()

1 files changed, 34 insertions, 41 deletions

diff --git a/mknes.h b/mknes.h
index ed22652..b8bf87f 100644
--- a/mknes.h
+++ b/mknes.h
@@ -21,19 +21,33 @@
 #define MIRROR_FOURSCREEN 2
 
 struct ppu_state {
-	uint8_t pixels[256 * 240];
-
-	uint8_t oam[256];
+	uint32_t scanline;
+	uint32_t dot;
+	uint32_t bg_shift_pattern_low;
+	uint32_t bg_shift_pattern_high;
+	uint32_t bg_shift_attrib_low;
+	uint32_t bg_shift_attrib_high;
+	uint8_t bg_next_tile_id;
+	uint8_t bg_next_tile_attrib;
+	uint8_t bg_next_tile_lsb;
+	uint8_t bg_next_tile_msb;
 	uint8_t oam_addr;
 	uint8_t oam_data;
+
+	uint8_t pixels[256 * 240] __attribute__((aligned(64)));
+	uint8_t oam[256];
 	uint8_t secondary_oam[32];
+	uint8_t palette[0x20];
+	uint8_t sprite_indexes[8];
+	uint32_t sprite_patterns[8];
+	uint8_t sprite_positions[8];
+	uint8_t sprite_priorities[8];
+	uint8_t sprite_shift_lo[8];
+	uint8_t sprite_shift_hi[8];
 
 	uint8_t reg_ctrl;
 	uint8_t reg_mask;
 	uint8_t reg_status;
-	uint8_t reg_scroll[2];
-	uint8_t reg_addr[2];
-	uint8_t reg_latch;
 
 	uint32_t vram_addr;
 	uint32_t temp_addr;
@@ -44,33 +58,11 @@ struct ppu_state {
 
 	uint8_t open_bus;
 
-	uint8_t palette[0x20];
-
-	uint32_t scanline;
-	uint32_t dot;
-	uint8_t even_frame;
 	uint8_t frame_ready;
 
-	uint8_t sprite_indexes[8];
 	uint8_t sprite_zero_hit_possible;
 	uint8_t sprite_count;
-	uint32_t sprite_patterns[8];
-	uint8_t sprite_positions[8];
-	uint8_t sprite_priorities[8];
-	uint8_t sprite_shift_lo[8];
-	uint8_t sprite_shift_hi[8];
-
-	uint32_t bg_shift_pattern_low;
-	uint32_t bg_shift_pattern_high;
-	uint32_t bg_shift_attrib_low;
-	uint32_t bg_shift_attrib_high;
-
-	uint8_t bg_next_tile_id;
-	uint8_t bg_next_tile_attrib;
-	uint8_t bg_next_tile_lsb;
-	uint8_t bg_next_tile_msb;
-};
-
+} __attribute__((packed, aligned(64)));
 
 struct cpu_state {
 	uint32_t pc;	// Program Counter
@@ -81,38 +73,39 @@ struct cpu_state {
 	uint8_t p;		// Processor Status Flags (this can be expanded with separate flags if needed)
 	uint8_t n;		// Negative Flag
 	uint8_t v;		// Overflow Flag
-	// uint8_t b;		// Break Flag (Set by BRK instruction)
+	// uint8_t b;		// Break Flag (Set by BRK instruction) -- does not exist outside the stack
 	uint8_t d;		// Decimal Flag
 	uint8_t i;		// Interrupt Disable Flag
 	uint8_t z;		// Zero Flag
 	uint8_t c;		// Carry Flag
 // --
 	uint8_t die;	// KIL instruction found!
-};
+} __attribute__((packed, aligned(64)));
 
 
 struct ines_state {
 	uint32_t mapper;
+	uint32_t submapper;
 	uint8_t mirroring;	// 0 = H, 1 = V, 2 = 4-screen
 	uint32_t prg_size;
 	uint32_t chr_size;
 };
 
 struct nes_state {
+	size_t cycles;
 	struct ines_state ines;
 	struct cpu_state cpu;
-	struct ppu_state ppu;
-	struct mapper mapper;
-	union mapper_data map;
-	size_t cycles;
 	uint8_t irq_pending;
 	uint8_t nmi_pending;
-	uint8_t ram[0x800];
-	uint8_t sram[0x2000];
-	uint8_t ciram[0x1000];				// NOTE(peter): Originally 0x800 bytes, but extended as it should work for up to fourway, this is optimization, reality is 2kb, but there is no side-effects, so this is fine!
-	uint8_t prg_rom[4 * 1024 * 1024];
-	uint8_t chr_rom[4 * 1024 * 1024];
-};
+	struct ppu_state ppu;
+	struct mapper_entry mapper;
+	union mapper_data map;
+	uint8_t ram[0x800] __attribute__((aligned(64)));
+	uint8_t sram[0x2000] __attribute__((aligned(64)));
+	uint8_t ciram[0x1000] __attribute__((aligned(64)));				// NOTE(peter): Originally 0x800 bytes, but extended as it should work for up to fourway, this is optimization, reality is 2kb, but there is no side-effects, so this is fine!
+	uint8_t prg_rom[4 * 1024 * 1024] __attribute__((aligned(64)));
+	uint8_t chr_rom[4 * 1024 * 1024] __attribute__((aligned(64)));
+} __attribute__((aligned(64)));
 
 
 __attribute__((aligned(4096))) static uint32_t nes_palette[64] = {