diff --git a/src/core/exception_handler.c b/src/core/exception_handler.c
index a608e624..15c371f8 100644
--- a/src/core/exception_handler.c
+++ b/src/core/exception_handler.c
@@ -57,7 +57,7 @@ void exception_handler_remove(struct exception_handler *handler) {
   }
 }
 
-int exception_handler_handle(struct exception *ex) {
+int exception_handler_handle(struct exception_state *ex) {
   list_for_each_entry(handler, &live_handlers, struct exception_handler, it) {
     if (handler->cb(handler->data, ex)) {
       return 1;
diff --git a/src/core/exception_handler.h b/src/core/exception_handler.h
index deebacc0..0288348c 100644
--- a/src/core/exception_handler.h
+++ b/src/core/exception_handler.h
@@ -3,10 +3,10 @@
 
 #include <stdint.h>
 
-struct exception;
+struct exception_state;
 struct exception_handler;
 
-typedef int (*exception_handler_cb)(void *data, struct exception *ex);
+typedef int (*exception_handler_cb)(void *, struct exception_state *);
 
 enum exception_type {
   EX_ACCESS_VIOLATION,
@@ -21,7 +21,7 @@ union thread_state {
   uint64_t r[17];
 };
 
-struct exception {
+struct exception_state {
   enum exception_type type;
   uintptr_t fault_addr;
   uintptr_t pc;
@@ -34,6 +34,6 @@ void exception_handler_uninstall_platform();
 struct exception_handler *exception_handler_add(void *data,
                                                 exception_handler_cb cb);
 void exception_handler_remove(struct exception_handler *handler);
-int exception_handler_handle(struct exception *ex);
+int exception_handler_handle(struct exception_state *ex);
 
 #endif
diff --git a/src/core/exception_handler_linux.c b/src/core/exception_handler_linux.c
index 87f53835..8db63cc9 100644
--- a/src/core/exception_handler_linux.c
+++ b/src/core/exception_handler_linux.c
@@ -49,7 +49,7 @@ static void signal_handler(int signo, siginfo_t *info, void *ctx) {
   ucontext_t *uctx = ctx;
 
   /* convert signal to internal exception */
-  struct exception ex;
+  struct exception_state ex;
   ex.type = signo == SIGSEGV ? EX_ACCESS_VIOLATION : EX_INVALID_INSTRUCTION;
   ex.fault_addr = (uintptr_t)info->si_addr;
   ex.pc = uctx->uc_mcontext.gregs[REG_RIP];
diff --git a/src/core/exception_handler_mac.c b/src/core/exception_handler_mac.c
index b6124d83..e0748570 100644
--- a/src/core/exception_handler_mac.c
+++ b/src/core/exception_handler_mac.c
@@ -86,7 +86,7 @@ kern_return_t catch_exception_raise(mach_port_t exception_port,
   }
 
   /* convert mach exception to internal exception */
-  struct exception ex;
+  struct exception_state ex;
   ex.type = exception == EXC_BAD_ACCESS ? EX_ACCESS_VIOLATION
                                         : EX_INVALID_INSTRUCTION;
   ex.fault_addr = exc_state.__faultvaddr;
diff --git a/src/core/exception_handler_win.c b/src/core/exception_handler_win.c
index 3c8741d8..a0bff245 100644
--- a/src/core/exception_handler_win.c
+++ b/src/core/exception_handler_win.c
@@ -48,7 +48,7 @@ static LONG CALLBACK exception_handler(PEXCEPTION_POINTERS ex_info) {
   }
 
   /* convert signal to internal exception */
-  struct exception ex;
+  struct exception_state ex;
   ex.type = code == STATUS_ACCESS_VIOLATION ? EX_ACCESS_VIOLATION
                                             : EX_INVALID_INSTRUCTION;
   ex.fault_addr = ex_info->ExceptionRecord->ExceptionInformation[1];
diff --git a/src/core/math.h b/src/core/math.h
index 98c45f91..c6fca74e 100644
--- a/src/core/math.h
+++ b/src/core/math.h
@@ -2,6 +2,7 @@
 #define REDREAM_MATH_H
 
 #include <float.h>
+#include <math.h>
 #include <stdint.h>
 
 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
diff --git a/src/core/memory.c b/src/core/memory.c
index be421111..91c5f81d 100644
--- a/src/core/memory.c
+++ b/src/core/memory.c
@@ -26,7 +26,7 @@ struct memory_watcher {
 
 static struct memory_watcher *watcher;
 
-static int watcher_handle_exception(void *ctx, struct exception *ex);
+static int watcher_handle_exception(void *ctx, struct exception_state *ex);
 
 static void watcher_create() {
   watcher = calloc(1, sizeof(struct memory_watcher));
@@ -47,7 +47,7 @@ static void watcher_destroy() {
   watcher = NULL;
 }
 
-static int watcher_handle_exception(void *ctx, struct exception *ex) {
+static int watcher_handle_exception(void *ctx, struct exception_state *ex) {
   int handled = 0;
 
   struct interval_tree_it it;
diff --git a/src/core/memory.h b/src/core/memory.h
index 321dcf9d..6514d244 100644
--- a/src/core/memory.h
+++ b/src/core/memory.h
@@ -3,7 +3,7 @@
 
 #include <stddef.h>
 
-struct exception;
+struct exception_state;
 
 /*
  * page protection
@@ -43,7 +43,7 @@ enum memory_watch_type {
   WATCH_SINGLE_WRITE,
 };
 
-typedef void (*memory_watch_cb)(const struct exception *, void *);
+typedef void (*memory_watch_cb)(const struct exception_state *, void *);
 
 struct memory_watch *add_single_write_watch(const void *ptr, size_t size,
                                             memory_watch_cb cb, void *data);
diff --git a/src/emulator.c b/src/emulator.c
index 6e25f337..0447166b 100644
--- a/src/emulator.c
+++ b/src/emulator.c
@@ -151,7 +151,7 @@ static void emu_dirty_modified_textures(struct emu *emu) {
   list_clear(&emu->modified_textures);
 }
 
-static void emu_texture_modified(const struct exception *ex, void *data) {
+static void emu_texture_modified(const struct exception_state *ex, void *data) {
   struct emu_texture *tex = data;
   tex->texture_watch = NULL;
 
@@ -161,7 +161,7 @@ static void emu_texture_modified(const struct exception *ex, void *data) {
   }
 }
 
-static void emu_palette_modified(const struct exception *ex, void *data) {
+static void emu_palette_modified(const struct exception_state *ex, void *data) {
   struct emu_texture *tex = data;
   tex->palette_watch = NULL;
 
diff --git a/src/hw/aica/aica.c b/src/hw/aica/aica.c
index a906c997..a5329de4 100644
--- a/src/hw/aica/aica.c
+++ b/src/hw/aica/aica.c
@@ -1,7 +1,7 @@
-#include <math.h>
 #include "hw/aica/aica.h"
 #include "core/filesystem.h"
 #include "core/log.h"
+#include "core/math.h"
 #include "core/option.h"
 #include "core/profiler.h"
 #include "dreamcast.h"
diff --git a/src/hw/pvr/tr.c b/src/hw/pvr/tr.c
index bd05fae3..4762c571 100644
--- a/src/hw/pvr/tr.c
+++ b/src/hw/pvr/tr.c
@@ -1,8 +1,7 @@
-#include <math.h>
-#include <string.h>
 #include "hw/pvr/tr.h"
 #include "core/assert.h"
 #include "core/core.h"
+#include "core/math.h"
 #include "core/profiler.h"
 #include "core/sort.h"
 #include "hw/pvr/pixel_convert.h"
diff --git a/src/hw/rom/boot.c b/src/hw/rom/boot.c
index fda0e28f..02669f26 100644
--- a/src/hw/rom/boot.c
+++ b/src/hw/rom/boot.c
@@ -1,16 +1,14 @@
-#include <stdio.h>
 #include "hw/rom/boot.h"
+#include "core/filesystem.h"
 #include "core/md5.h"
 #include "core/option.h"
 #include "dreamcast.h"
 
 DEFINE_OPTION_STRING(bios, "dc_boot.bin", "Path to boot rom");
 
-#define BIOS_SIZE 0x00200000
-
 struct boot {
   struct device;
-  uint8_t rom[BIOS_SIZE];
+  uint8_t rom[0x00200000];
 };
 
 static uint32_t boot_rom_read(struct boot *boot, uint32_t addr,
@@ -29,7 +27,7 @@ static int boot_validate(struct boot *boot) {
   /* compare the rom's md5 against known good bios roms */
   MD5_CTX md5_ctx;
   MD5_Init(&md5_ctx);
-  MD5_Update(&md5_ctx, boot->rom, BIOS_SIZE);
+  MD5_Update(&md5_ctx, boot->rom, sizeof(boot->rom));
   char result[33];
   MD5_Final(result, &md5_ctx);
 
@@ -42,8 +40,10 @@ static int boot_validate(struct boot *boot) {
   return 0;
 }
 
-static int boot_load_rom(struct boot *boot, const char *path) {
-  FILE *fp = fopen(path, "rb");
+static int boot_load_rom(struct boot *boot) {
+  const char *filename = OPTION_bios;
+
+  FILE *fp = fopen(filename, "rb");
   if (!fp) {
     return 0;
   }
@@ -52,8 +52,9 @@ static int boot_load_rom(struct boot *boot, const char *path) {
   int size = ftell(fp);
   fseek(fp, 0, SEEK_SET);
 
-  if (size != BIOS_SIZE) {
-    LOG_WARNING("Boot rom size mismatch, is %d, expected %d", size, BIOS_SIZE);
+  if (size != (int)sizeof(boot->rom)) {
+    LOG_WARNING("boot rom size mismatch, is %d, expected %d", size,
+                sizeof(boot->rom));
     fclose(fp);
     return 0;
   }
@@ -63,7 +64,18 @@ static int boot_load_rom(struct boot *boot, const char *path) {
   fclose(fp);
 
   if (!boot_validate(boot)) {
-    LOG_WARNING("Invalid BIOS file");
+    LOG_WARNING("invalid BIOS file");
+    return 0;
+  }
+
+  return 1;
+}
+
+static int boot_init(struct device *dev) {
+  struct boot *boot = (struct boot *)dev;
+
+  if (!boot_load_rom(boot)) {
+    LOG_WARNING("failed to load boot rom");
     return 0;
   }
 
@@ -74,22 +86,10 @@ void boot_destroy(struct boot *boot) {
   dc_destroy_device((struct device *)boot);
 }
 
-static int boot_init(struct device *dev) {
-  struct boot *boot = (struct boot *)dev;
-
-  if (!boot_load_rom(boot, OPTION_bios)) {
-    LOG_WARNING("Failed to load boot rom");
-    return 0;
-  }
-
-  return 1;
-}
-
 struct boot *boot_create(struct dreamcast *dc) {
   struct boot *boot =
       dc_create_device(dc, sizeof(struct boot), "boot", &boot_init);
   return boot;
-  ;
 }
 
 /* clang-format off */
diff --git a/src/hw/rom/flash.c b/src/hw/rom/flash.c
index b0911b1b..7ec52719 100644
--- a/src/hw/rom/flash.c
+++ b/src/hw/rom/flash.c
@@ -1,16 +1,14 @@
-/* there doesn't seem to be any documentation on the flash rom used by the
-   dreamcast, but it appears to implement the JEDEC CFI standard */
-
 #include <stdio.h>
 #include "hw/rom/flash.h"
 #include "core/filesystem.h"
 #include "core/option.h"
 #include "dreamcast.h"
 
-DEFINE_OPTION_STRING(flash, "dc_flash.bin", "Path to flash rom");
-
 #define FLASH_SIZE 0x00020000
 #define FLASH_SECTOR_SIZE 0x4000
+
+/* there doesn't seem to be any documentation on the flash rom used by the
+   dreamcast, but it appears to implement the JEDEC CFI standard */
 #define FLASH_CMD_NONE 0x0
 #define FLASH_CMD_ERASE 0x80
 #define FLASH_CMD_ERASE_CHIP 0x10
@@ -19,12 +17,15 @@ DEFINE_OPTION_STRING(flash, "dc_flash.bin", "Path to flash rom");
 
 struct flash {
   struct device;
+
+  uint8_t rom[FLASH_SIZE];
+
   /* cmd parsing state */
   int cmd;
   int cmd_state;
 };
 
-const char *flash_bin_path() {
+static const char *flash_bin_path() {
   static char filename[PATH_MAX];
 
   if (!filename[0]) {
@@ -36,93 +37,65 @@ const char *flash_bin_path() {
   return filename;
 }
 
-static void flash_read_bin(int offset, void *buffer, int size) {
-  const char *flash_path = flash_bin_path();
-  FILE *file = fopen(flash_path, "rb");
-  CHECK_NOTNULL(file, "Failed to open %s", flash_path);
-  int r = fseek(file, offset, SEEK_SET);
-  CHECK_NE(r, -1);
-  r = (int)fread(buffer, 1, size, file);
-  CHECK_EQ(r, size);
-  fclose(file);
-}
-
-static void flash_write_bin(int offset, const void *buffer, int size) {
-  const char *flash_path = flash_bin_path();
-  FILE *file = fopen(flash_path, "r+b");
-  CHECK_NOTNULL(file, "Failed to open %s", flash_path);
-  int r = fseek(file, offset, SEEK_SET);
-  CHECK_NE(r, -1);
-  r = (int)fwrite(buffer, 1, size, file);
-  CHECK_EQ(r, size);
-  fclose(file);
-}
-
-static int flash_init_bin() {
-  /* check to see if a persistent flash rom exists in the app directory */
-  const char *flash_path = flash_bin_path();
-  if (fs_exists(flash_path)) {
-    return 1;
-  }
-
-  /* if it doesn't, read the original flash rom from the command line path */
-  uint8_t rom[FLASH_SIZE];
-
-  LOG_INFO("Initializing flash rom from %s", OPTION_flash);
-
-  FILE *src = fopen(OPTION_flash, "rb");
-  if (!src) {
-    LOG_WARNING("Failed to load %s", OPTION_flash);
-    return 0;
-  }
-
-  fseek(src, 0, SEEK_END);
-  int size = ftell(src);
-  fseek(src, 0, SEEK_SET);
-
-  if (size != FLASH_SIZE) {
-    LOG_WARNING("Flash size mismatch, is %d, expected %d", size, FLASH_SIZE);
-    fclose(src);
-    return 0;
-  }
-
-  int n = (int)fread(rom, 1, size, src);
-  CHECK_EQ(n, size);
-  fclose(src);
-
-  /* and copy it to the app directory */
-  FILE *dst = fopen(flash_path, "wb");
-  CHECK_NOTNULL("Failed to open %s", flash_path);
-  int r = (int)fwrite(rom, 1, size, dst);
-  CHECK_EQ(r, size);
-  fclose(dst);
-
-  return 1;
-}
-
 static uint32_t flash_cmd_read(struct flash *flash, uint32_t addr,
                                uint32_t data_mask) {
   int size = DATA_SIZE();
   uint32_t mem;
-  flash_read_bin(addr, &mem, size);
+  flash_read(flash, addr, &mem, size);
   return mem & data_mask;
 }
 
+static void flash_save_rom(struct flash *flash) {
+  const char *filename = flash_bin_path();
+
+  FILE *fp = fopen(filename, "wb");
+  int n = (int)fwrite(flash->rom, 1, sizeof(flash->rom), fp);
+  CHECK_EQ(n, (int)sizeof(flash->rom));
+  fclose(fp);
+}
+
+static int flash_load_rom(struct flash *flash) {
+  const char *filename = flash_bin_path();
+
+  FILE *fp = fopen(filename, "rb");
+  if (!fp) {
+    LOG_WARNING("failed to load %s", filename);
+    return 0;
+  }
+
+  fseek(fp, 0, SEEK_END);
+  int size = ftell(fp);
+  fseek(fp, 0, SEEK_SET);
+
+  if (size != sizeof(flash->rom)) {
+    LOG_WARNING("flash size mismatch, is %d, expected %d", size,
+                (int)sizeof(flash->rom));
+    fclose(fp);
+    return 0;
+  }
+
+  int n = (int)fread(flash->rom, 1, size, fp);
+  CHECK_EQ(n, size);
+  fclose(fp);
+
+  return 1;
+}
+
 static void flash_cmd_program(struct flash *flash, uint32_t addr, uint32_t data,
                               uint32_t data_mask) {
   /* programming can only clear bits to 0 */
   int size = DATA_SIZE();
   uint32_t mem;
-  flash_read_bin(addr, &mem, size);
+  flash_read(flash, addr, &mem, size);
   mem &= data;
-  flash_write_bin(addr, &mem, size);
+  flash_write(flash, addr, &mem, size);
 }
 
 static void flash_cmd_erase_chip(struct flash *flash) {
   /* erasing resets bits to 1 */
   uint8_t empty_chip[FLASH_SIZE];
   memset(empty_chip, 0xff, sizeof(empty_chip));
-  flash_write_bin(0, empty_chip, sizeof(empty_chip));
+  flash_write(flash, 0, empty_chip, sizeof(empty_chip));
 }
 
 static void flash_cmd_erase_sector(struct flash *flash, uint32_t addr) {
@@ -132,7 +105,7 @@ static void flash_cmd_erase_sector(struct flash *flash, uint32_t addr) {
   /* erasing resets bits to 1 */
   uint8_t empty_sector[FLASH_SECTOR_SIZE];
   memset(empty_sector, 0xff, sizeof(empty_sector));
-  flash_write_bin(addr, empty_sector, sizeof(empty_sector));
+  flash_write(flash, addr, empty_sector, sizeof(empty_sector));
 }
 
 static uint32_t flash_rom_read(struct flash *flash, uint32_t addr,
@@ -189,7 +162,7 @@ static void flash_rom_write(struct flash *flash, uint32_t addr, uint32_t data,
     } break;
 
     default:
-      LOG_FATAL("Unexpected flash command state %d", flash->cmd_state);
+      LOG_FATAL("unexpected flash command state %d", flash->cmd_state);
       break;
   }
 }
@@ -197,21 +170,30 @@ static void flash_rom_write(struct flash *flash, uint32_t addr, uint32_t data,
 static int flash_init(struct device *dev) {
   struct flash *flash = (struct flash *)dev;
 
-  if (!flash_init_bin()) {
-    LOG_WARNING("Failed to load flash rom");
+  if (!flash_load_rom(flash)) {
     return 0;
   }
 
   return 1;
 }
 
+void flash_write(struct flash *flash, int offset, const void *data, int size) {
+  memcpy(&flash->rom[offset], data, size);
+}
+
+void flash_read(struct flash *flash, int offset, void *data, int size) {
+  memcpy(data, &flash->rom[offset], size);
+}
+
 void flash_destroy(struct flash *flash) {
+  flash_save_rom(flash);
   dc_destroy_device((struct device *)flash);
 }
 
 struct flash *flash_create(struct dreamcast *dc) {
   struct flash *flash =
       dc_create_device(dc, sizeof(struct flash), "flash", &flash_init);
+
   return flash;
 }
 
diff --git a/src/hw/rom/flash.h b/src/hw/rom/flash.h
index c9598400..6510d71c 100644
--- a/src/hw/rom/flash.h
+++ b/src/hw/rom/flash.h
@@ -1,5 +1,5 @@
-#ifndef FLASH_H
-#define FLASH_H
+#ifndef FLASHROM_H
+#define FLASHROM_H
 
 #include "memory.h"
 
@@ -11,4 +11,7 @@ AM_DECLARE(flash_rom_map);
 struct flash *flash_create(struct dreamcast *dc);
 void flash_destroy(struct flash *flash);
 
+void flash_read(struct flash *flash, int offset, void *data, int size);
+void flash_write(struct flash *flash, int offset, const void *data, int size);
+
 #endif
diff --git a/src/hw/sh4/sh4.c b/src/hw/sh4/sh4.c
index ad79b188..c83dafca 100644
--- a/src/hw/sh4/sh4.c
+++ b/src/hw/sh4/sh4.c
@@ -12,7 +12,6 @@
 #include "jit/frontend/sh4/sh4_fallback.h"
 #include "jit/frontend/sh4/sh4_frontend.h"
 #include "jit/frontend/sh4/sh4_guest.h"
-#include "jit/ir/ir.h"
 #include "jit/jit.h"
 #include "memory.h"
 #include "render/imgui.h"
diff --git a/src/jit/backend/interp/interp_backend.c b/src/jit/backend/interp/interp_backend.c
index 2526e029..3d1e85fb 100644
--- a/src/jit/backend/interp/interp_backend.c
+++ b/src/jit/backend/interp/interp_backend.c
@@ -42,7 +42,7 @@ static void interp_backend_run_code(struct jit_backend *base, int cycles) {
 }
 
 static int interp_backend_handle_exception(struct jit_backend *base,
-                                           struct exception *ex) {
+                                           struct exception_state *ex) {
   return 0;
 }
 
diff --git a/src/jit/backend/jit_backend.h b/src/jit/backend/jit_backend.h
index 6ab4f984..ed445fcb 100644
--- a/src/jit/backend/jit_backend.h
+++ b/src/jit/backend/jit_backend.h
@@ -3,7 +3,7 @@
 
 #include <stdint.h>
 
-struct exception;
+struct exception_state;
 struct ir;
 struct jit;
 struct jit_block;
@@ -27,7 +27,7 @@ struct jit_backend {
   void (*reset)(struct jit_backend *);
   int (*assemble_code)(struct jit_backend *, struct jit_block *, struct ir *);
   void (*dump_code)(struct jit_backend *, const uint8_t *, int);
-  int (*handle_exception)(struct jit_backend *, struct exception *);
+  int (*handle_exception)(struct jit_backend *, struct exception_state *);
 
   /* dispatch interface */
   void (*run_code)(struct jit_backend *, int);
diff --git a/src/jit/backend/x64/x64_backend.cc b/src/jit/backend/x64/x64_backend.cc
index 2b426637..62fda04a 100644
--- a/src/jit/backend/x64/x64_backend.cc
+++ b/src/jit/backend/x64/x64_backend.cc
@@ -500,7 +500,7 @@ static void x64_backend_emit_constants(struct x64_backend *backend) {
 }
 
 static int x64_backend_handle_exception(struct jit_backend *base,
-                                        struct exception *ex) {
+                                        struct exception_state *ex) {
   struct x64_backend *backend = container_of(base, struct x64_backend, base);
   struct jit_guest *guest = backend->base.jit->guest;
 
diff --git a/src/jit/frontend/sh4/sh4_fallback.c b/src/jit/frontend/sh4/sh4_fallback.c
index 6d61dd08..8677b1e3 100644
--- a/src/jit/frontend/sh4/sh4_fallback.c
+++ b/src/jit/frontend/sh4/sh4_fallback.c
@@ -1,7 +1,7 @@
-#include <math.h>
 #include "jit/frontend/sh4/sh4_fallback.h"
 #include "core/assert.h"
 #include "core/log.h"
+#include "core/math.h"
 #include "jit/frontend/sh4/sh4_context.h"
 #include "jit/frontend/sh4/sh4_frontend.h"
 #include "jit/frontend/sh4/sh4_guest.h"
diff --git a/src/jit/jit.c b/src/jit/jit.c
index bcf335c3..574ceaeb 100644
--- a/src/jit/jit.c
+++ b/src/jit/jit.c
@@ -334,7 +334,7 @@ void jit_compile_block(struct jit *jit, uint32_t guest_addr) {
   PROF_LEAVE();
 }
 
-static int jit_handle_exception(void *data, struct exception *ex) {
+static int jit_handle_exception(void *data, struct exception_state *ex) {
   struct jit *jit = data;
 
   /* see if there is a cached block corresponding to the current pc */