diff --git a/.gitignore b/.gitignore
index bf5c80b..5bc8246 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+*.a
 *.o
 *.u
 *.z
diff --git a/Makefile b/Makefile
index c962e5f..e0e9a81 100644
--- a/Makefile
+++ b/Makefile
@@ -217,9 +217,11 @@ else ifeq ($(platform), psp1)
 	CFLAGS += -DPSP -G0
 	CFLAGS += -I$(shell psp-config --pspsdk-path)/include
 	CFLAGS += -march=allegrex -mfp32 -mgp32 -mlong32 -mabi=eabi
-	CFLAGS += -fomit-frame-pointer -ffast-math -fstrict-aliasing
+	CFLAGS += -fomit-frame-pointer -ffast-math
 	CFLAGS += -falign-functions=32 -falign-loops -falign-labels -falign-jumps
 	STATIC_LINKING = 1
+	HAVE_DYNAREC = 1
+	CPU_ARCH := mips
 
 # Vita
 else ifeq ($(platform), vita)
diff --git a/Makefile.common b/Makefile.common
index 312b18b..dc8c106 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -29,6 +29,9 @@ endif
 ifeq ($(CPU_ARCH), arm)
 SOURCES_ASM += $(CORE_DIR)/arm/arm_stub.S
 endif
+ifeq ($(CPU_ARCH), mips)
+SOURCES_ASM += $(CORE_DIR)/psp/mips_stub.S
+endif
 endif
 
 ifeq ($(CPU_ARCH), arm)
diff --git a/common.h b/common.h
index 8b1df6b..5d52981 100644
--- a/common.h
+++ b/common.h
@@ -49,7 +49,7 @@
 // Huge thanks to pollux for the heads up on using native file I/O
 // functions on PSP for vastly improved memstick performance.
 
-#ifdef PSP_BUILD
+#ifdef PSP
   #define fastcall
 
   #include <pspkernel.h>
@@ -90,12 +90,6 @@
   #include <stdio.h>
 #else
 
-#define GBA_SCREEN_WIDTH  (240)
-#define GBA_SCREEN_HEIGHT (160)
-#define GBA_SCREEN_PITCH  (240)
-
-void switch_to_main_thread(void);
-
   typedef unsigned char u8;
   typedef signed char s8;
   typedef unsigned short int u16;
@@ -133,6 +127,12 @@ void switch_to_main_thread(void);
 
 #endif
 
+#define GBA_SCREEN_WIDTH  (240)
+#define GBA_SCREEN_HEIGHT (160)
+#define GBA_SCREEN_PITCH  (240)
+
+void switch_to_main_thread(void);
+
 // These must be variables, not constants.
 
 #define file_read_variable(filename_tag, variable)                            \
diff --git a/cpu.h b/cpu.h
index 3ed9f07..2659b10 100644
--- a/cpu.h
+++ b/cpu.h
@@ -119,7 +119,7 @@ s32 translate_block_arm(u32 pc, translation_region_type translation_region,
 s32 translate_block_thumb(u32 pc, translation_region_type translation_region,
  u32 smc_enable);
 
-#if defined(PSP_BUILD)
+#if defined(PSP)
 
 #define ROM_TRANSLATION_CACHE_SIZE (1024 * 512 * 4)
 #define RAM_TRANSLATION_CACHE_SIZE (1024 * 384)
diff --git a/cpu_threaded.c b/cpu_threaded.c
index c3f172b..7386d0c 100644
--- a/cpu_threaded.c
+++ b/cpu_threaded.c
@@ -227,7 +227,7 @@ extern u8 bit_count[256];
   u32 offset = opcode & 0x07FF                                                \
 
 
-#ifdef PSP_BUILD
+#ifdef PSP
 
 #include "psp/mips_emit.h"
 
@@ -257,8 +257,10 @@ static INLINE void RW_END(void)
 
 /* Cache invalidation */
 
-#if defined(PSP_BUILD)
+#if defined(PSP)
 #define translate_invalidate_dcache() sceKernelDcacheWritebackAll()
+#define invalidate_icache_region(addr, size) (void)0
+
 #elif defined(VITA)
 #define translate_invalidate_dcache_one(which)                                \
   if (which##_translation_ptr > last_##which##_translation_ptr)               \
diff --git a/gba_memory.c b/gba_memory.c
index 15ad808..970fbee 100644
--- a/gba_memory.c
+++ b/gba_memory.c
@@ -343,7 +343,7 @@ gamepak_swap_entry_type *gamepak_memory_map;
 // This is global so that it can be kept open for large ROMs to swap
 // pages from, so there's no slowdown with opening and closing the file
 // a lot.
-#ifdef PSP_BUILD
+#ifdef PSP
 
 file_tag_type gamepak_file_large = -1;
 
@@ -2391,9 +2391,7 @@ static s32 load_game_config(char *gamepak_title, char *gamepak_code, char *gamep
     fclose(config_file);
   }
 
-#ifndef PSP_BUILD
   printf("game config missing\n");
-#endif
   return -1;
 }
 
@@ -2418,7 +2416,7 @@ static s32 load_gamepak_raw(const char *name)
 
       file_close(gamepak_file);
 
-#ifdef PSP_BUILD
+#ifdef PSP
       gamepak_file_large = -1;
 #else
       gamepak_file_large = NULL;
diff --git a/main.c b/main.c
index bc8a408..0f9bb88 100644
--- a/main.c
+++ b/main.c
@@ -280,13 +280,15 @@ void reset_gba(void)
   reset_sound();
 }
 
-u32 file_length(const char *dummy, FILE *fp)
+#ifdef PSP
+u32 file_length(const char *filename, s32 dummy)
 {
-#ifdef PSP_BUILD
   SceIoStat stats;
   sceIoGetstat(filename, &stats);
   return stats.st_size;
 #else
+u32 file_length(const char *dummy, FILE *fp)
+{
   u32 length;
 
   fseek(fp, 0, SEEK_END);
diff --git a/main.h b/main.h
index f34d7db..1f730c0 100644
--- a/main.h
+++ b/main.h
@@ -83,8 +83,8 @@ void main_write_savestate(void);
 void main_read_savestate(void);
 
 
-#ifdef PSP_BUILD
-u32 file_length(char *filename, s32 dummy);
+#ifdef PSP
+u32 file_length(const char *filename, s32 dummy);
 #else
 u32 file_length(const char *dummy, FILE *fp);
 #endif
diff --git a/psp/mips_emit.h b/psp/mips_emit.h
index f2ab1e8..9510156 100644
--- a/psp/mips_emit.h
+++ b/psp/mips_emit.h
@@ -1553,9 +1553,13 @@ typedef enum
 
 #define arm_generate_op_imm(name, load_op)                                    \
   arm_decode_data_proc_imm(opcode);                                           \
+  ror(imm, imm, imm_ror);                                                     \
   arm_op_check_##load_op();                                                   \
   generate_op_##name##_imm(arm_to_mips_reg[rd], arm_to_mips_reg[rn])          \
 
+#define arm_generate_op_imm_flags(name, load_op)                              \
+  arm_generate_op_imm(name, load_op)                                          \
+
 #define arm_data_proc(name, type, flags_op)                                   \
 {                                                                             \
   arm_generate_op_##type(name, yes);                                          \
@@ -2137,10 +2141,16 @@ u32 execute_store_cpsr_body(u32 _cpsr, u32 store_mask, u32 address)
   mips_emit_addiu(arm_to_mips_reg[_rd], reg_r13, (imm * 4));                  \
 }                                                                             \
 
-#define thumb_adjust_sp(value)                                                \
+#define thumb_adjust_sp_up()                                                  \
+  mips_emit_addiu(reg_r13, reg_r13, (imm * 4));                               \
+
+#define thumb_adjust_sp_down()                                                \
+  mips_emit_addiu(reg_r13, reg_r13, -(imm * 4));                              \
+
+#define thumb_adjust_sp(direction)                                            \
 {                                                                             \
   thumb_decode_add_sp();                                                      \
-  mips_emit_addiu(reg_r13, reg_r13, (value));                                 \
+  thumb_adjust_sp_##direction();                                              \
 }                                                                             \
 
 // Decode types: shift, alu_op
@@ -2203,6 +2213,9 @@ u32 execute_store_cpsr_body(u32 _cpsr, u32 store_mask, u32 address)
 #define thumb_access_memory_generate_address_reg_imm(offset, reg_rb, reg_ro)  \
   mips_emit_addiu(reg_a0, arm_to_mips_reg[reg_rb], (offset))                  \
 
+#define thumb_access_memory_generate_address_reg_imm_sp(offset, reg_rb, reg_ro) \
+  mips_emit_addiu(reg_a0, arm_to_mips_reg[reg_rb], (offset * 4))              \
+
 #define thumb_access_memory_generate_address_reg_reg(offset, reg_rb, reg_ro)  \
   mips_emit_addu(reg_a0, arm_to_mips_reg[reg_rb], arm_to_mips_reg[reg_ro])    \
 
diff --git a/psp/mips_stub.S b/psp/mips_stub.S
index aaef70b..dd91ea8 100644
--- a/psp/mips_stub.S
+++ b/psp/mips_stub.S
@@ -3343,8 +3343,13 @@ ror_zero_shift:
 
 execute_arm_translate:
   addu $17, $4, $0                # load cycle counter register
-  lui $16, %hi(reg)               # load base register
-  addiu $16, %lo(reg)
+
+  lui $4, %hi(arm_reg)            # load arm_reg address into $4
+  addiu $4, %lo(arm_reg)
+
+  jal move_reg                    # update reg to point to arm_reg
+  addu $16, $4, $0                # copy address of arm_reg into $16
+
   extract_flags                   # load flag variables
 
   and $1, $1, 0x20                # see if Thumb bit is set in flags
@@ -3405,9 +3410,10 @@ iac_loop:
 memory_map_read:
   .space 0x8000
 
-reg:
+# This must be between memory_map_read and memory_map_write because it's used
+# to calculate their addresses elsewhere in this file.
+arm_reg:
   .space 0x100
 
 memory_map_write:
   .space 0x8000
-