diff --git a/source/core/Nes_Apu.h b/source/core/Nes_Apu.h
index 60c1983..da9ee5a 100644
--- a/source/core/Nes_Apu.h
+++ b/source/core/Nes_Apu.h
@@ -1,10 +1,10 @@
+#pragma once
 
 // NES 2A03 APU sound chip emulator
 
 // Nes_Snd_Emu 0.1.7
 
-#ifndef NES_APU_H
-#define NES_APU_H
+#include <cstdint>
 
 typedef long     nes_time_t; // CPU clock cycle count
 typedef unsigned nes_addr_t; // 16-bit memory address
@@ -172,4 +172,3 @@ inline nes_time_t Nes_Dmc::next_read_time() const
 
 inline nes_time_t Nes_Apu::next_dmc_read_time() const { return dmc.next_read_time(); }
 
-#endif
diff --git a/source/core/Nes_Cpu.cpp b/source/core/Nes_Cpu.cpp
index 4814fe7..4aa920f 100644
--- a/source/core/Nes_Cpu.cpp
+++ b/source/core/Nes_Cpu.cpp
@@ -255,18 +255,19 @@ Nes_Cpu::result_t Nes_Cpu::run( nes_time_t end )
   SET_STATUS( temp );
  }
 
+ uint32_t data;
+ uint8_t const* page;
+ uint8_t opcode;
+
 loop:
 
- uint8_t const* page = code_map [pc >> page_bits];
- uint8_t opcode = page [pc];
- pc++;
-
- if ( clock_count >= clock_limit )
-  goto stop;
+ page = code_map [pc >> page_bits];
+ opcode = page [pc++];
+ data = page [pc];
+ 
+ if ( clock_count >= clock_limit ) [[unlikely]] goto stop;
 
  clock_count += clock_table [opcode];
- unsigned data;
- data = page [pc];
 
  switch ( opcode )
  {
@@ -367,35 +368,6 @@ loop:
   nz = data;
   goto loop;
 
-#if 0
- case 0xA1: // LDA (ind,X)
-  IND_X
-  goto lda_ptr;
-
- case 0xB1: // LDA (ind),Y
-  IND_Y(true,true)
-  goto lda_ptr;
-
- case 0xB9: // LDA abs,Y
-  data += y;
-  goto lda_ind_common;
-
- case 0xBD: // LDA abs,X
-  data += x;
- lda_ind_common: {
-  HANDLE_PAGE_CROSSING( data );
-  int temp = data;
-  ADD_PAGE
-  if ( temp & 0x100 )
-   READ( data - 0x100 );
- }
- lda_ptr:
-  a = nz = READ( data );
-  pc++;
-  goto loop;
-#else
- // optimization of most commonly used memory read instructions
-
  case 0xB9:// LDA abs,Y
   data += y;
   data -= x;
@@ -440,8 +412,6 @@ loop:
   pc++;
   goto loop;
 
-#endif
-
 // Branch
 
  case 0x50: // BVC
diff --git a/source/core/Nes_Cpu.h b/source/core/Nes_Cpu.h
index 96b2660..14e5389 100644
--- a/source/core/Nes_Cpu.h
+++ b/source/core/Nes_Cpu.h
@@ -6,7 +6,7 @@
 #ifndef NES_CPU_H
 #define NES_CPU_H
 
-#include <stdint.h>
+#include <cstdint>
 #include "blargg_common.h"
 
 typedef long     nes_time_t; // clock cycle count