use UNLIKELY() macro (#554)

core/m68k/m68kcpu.c

@@ -292,7 +292,7 @@ void m68k_run(unsigned int cycles)
 
 #ifdef HOOK_CPU
     /* Trigger execution hook */
-    if (cpu_hook)
+    if (UNLIKELY(cpu_hook))
       cpu_hook(HOOK_M68K_E, 0, REG_PC, 0);
 #endif
 

core/m68k/m68kcpu.h

@@ -859,7 +859,7 @@ INLINE uint m68ki_read_8(uint address)
   else val = READ_BYTE(temp->base, (address) & 0xffff);
 
 #ifdef HOOK_CPU
-  if (cpu_hook)
+  if (UNLIKELY(cpu_hook))
     cpu_hook(HOOK_M68K_R, 1, address, val);
 #endif
 
@@ -879,7 +879,7 @@ INLINE uint m68ki_read_16(uint address)
   else val = *(uint16 *)(temp->base + ((address) & 0xffff));
 
 #ifdef HOOK_CPU
-  if (cpu_hook)
+  if (UNLIKELY(cpu_hook))
     cpu_hook(HOOK_M68K_R, 2, address, val);
 #endif
 
@@ -899,7 +899,7 @@ INLINE uint m68ki_read_32(uint address)
   else val = m68k_read_immediate_32(address);
 
 #ifdef HOOK_CPU
-  if (cpu_hook)
+  if (UNLIKELY(cpu_hook))
     cpu_hook(HOOK_M68K_R, 4, address, val);
 #endif
 
@@ -913,7 +913,7 @@ INLINE void m68ki_write_8(uint address, uint value)
   m68ki_set_fc(FLAG_S | FUNCTION_CODE_USER_DATA) /* auto-disable (see m68kcpu.h) */
 
 #ifdef HOOK_CPU
-  if (cpu_hook)
+  if (UNLIKELY(cpu_hook))
     cpu_hook(HOOK_M68K_W, 1, address, value);
 #endif
 
@@ -930,7 +930,7 @@ INLINE void m68ki_write_16(uint address, uint value)
   m68ki_check_address_error(address, MODE_WRITE, FLAG_S | FUNCTION_CODE_USER_DATA); /* auto-disable (see m68kcpu.h) */
 
 #ifdef HOOK_CPU
-  if (cpu_hook)
+  if (UNLIKELY(cpu_hook))
     cpu_hook(HOOK_M68K_W, 2, address, value);
 #endif
 
@@ -947,7 +947,7 @@ INLINE void m68ki_write_32(uint address, uint value)
   m68ki_check_address_error(address, MODE_WRITE, FLAG_S | FUNCTION_CODE_USER_DATA) /* auto-disable (see m68kcpu.h) */
 
 #ifdef HOOK_CPU
-  if (cpu_hook)
+  if (UNLIKELY(cpu_hook))
     cpu_hook(HOOK_M68K_W, 4, address, value);
 #endif
 

core/macros.h

@@ -53,6 +53,15 @@
 #define ALIGNED_(x) __attribute__ ((aligned(x)))
 #endif
 
+/* Provide the compiler with branch prediction information */
+#if defined(__GNUC__)
+#define LIKELY(x) __builtin_expect(!!(x), 1)
+#define UNLIKELY(x) __builtin_expect(!!(x), 0)
+#else
+#define LIKELY(x) x
+#define UNLIKELY(x) x
+#endif
+
 /* Default CD image file access (read-only) functions */
 /* If you need to override default stdio.h functions with custom filesystem API,
    redefine following macros in platform specific include file (osd.h) or Makefile

core/vdp_ctrl.c

@@ -2162,7 +2162,7 @@ static void vdp_bus_w(unsigned int data)
       }
 
 #ifdef HOOK_CPU
-      if (cpu_hook)
+      if (UNLIKELY(cpu_hook))
         cpu_hook(HOOK_VRAM_W, 2, addr, data);
 #endif
 
@@ -2211,7 +2211,7 @@ static void vdp_bus_w(unsigned int data)
       }
 
 #ifdef HOOK_CPU
-      if (cpu_hook)
+      if (UNLIKELY(cpu_hook))
         cpu_hook(HOOK_CRAM_W, 2, addr, data);
 #endif
 
@@ -2237,7 +2237,7 @@ static void vdp_bus_w(unsigned int data)
       }
 
 #ifdef HOOK_CPU
-      if (cpu_hook)
+      if (UNLIKELY(cpu_hook))
         cpu_hook(HOOK_VSRAM_W, 2, addr, data);
 #endif
 
@@ -2448,7 +2448,7 @@ static unsigned int vdp_68k_data_r_m5(void)
       data = *(uint16 *)&vram[addr & 0xFFFE];
 
 #ifdef HOOK_CPU
-      if (cpu_hook)
+      if (UNLIKELY(cpu_hook))
         cpu_hook(HOOK_VRAM_R, 2, addr, data);
 #endif
 
@@ -2477,7 +2477,7 @@ static unsigned int vdp_68k_data_r_m5(void)
       data |= (fifo[fifo_idx] & ~0x7FF);
 
 #ifdef HOOK_CPU
-      if (cpu_hook)
+      if (UNLIKELY(cpu_hook))
         cpu_hook(HOOK_VSRAM_R, 2, addr, data);
 #endif
 
@@ -2499,7 +2499,7 @@ static unsigned int vdp_68k_data_r_m5(void)
       data |= (fifo[fifo_idx] & ~0xEEE);
 
 #ifdef HOOK_CPU
-      if (cpu_hook)
+      if (UNLIKELY(cpu_hook))
         cpu_hook(HOOK_CRAM_R, 2, addr, data);
 #endif
 
@@ -2518,7 +2518,7 @@ static unsigned int vdp_68k_data_r_m5(void)
       data |= (fifo[fifo_idx] & ~0xFF);
 
 #ifdef HOOK_CPU
-      if (cpu_hook)
+      if (UNLIKELY(cpu_hook))
         cpu_hook(HOOK_VRAM_R, 2, addr, data);
 #endif