From fb95d5b59f2661b698987072c0545620ec686751 Mon Sep 17 00:00:00 2001
From: byuu <2107894+byuu@users.noreply.github.com>
Date: Sat, 12 Oct 2019 14:28:03 +0900
Subject: [PATCH] v111.5

Updated frame advance to run after first advance when paused previously.
Moved frame events into the CPU core to prevent PPU<>NMI race condition.
Credit to r5 for pointing out there being an issue during frame advance.
---
 bsnes/emulator/emulator.hpp          | 2 +-
 bsnes/sfc/cpu/timing.cpp             | 9 +++++++++
 bsnes/sfc/ppu-fast/ppu.cpp           | 6 ------
 bsnes/sfc/ppu/main.cpp               | 8 --------
 bsnes/target-bsnes/input/hotkeys.cpp | 5 ++---
 5 files changed, 12 insertions(+), 18 deletions(-)

diff --git a/bsnes/emulator/emulator.hpp b/bsnes/emulator/emulator.hpp
index 607b0fa7..9cb3fd1f 100644
--- a/bsnes/emulator/emulator.hpp
+++ b/bsnes/emulator/emulator.hpp
@@ -29,7 +29,7 @@ using namespace nall;
 
 namespace Emulator {
   static const string Name    = "bsnes";
-  static const string Version = "111.4";
+  static const string Version = "111.5";
   static const string Author  = "byuu";
   static const string License = "GPLv3";
   static const string Website = "https://byuu.org";
diff --git a/bsnes/sfc/cpu/timing.cpp b/bsnes/sfc/cpu/timing.cpp
index cd20e2e8..0c9cfe0f 100644
--- a/bsnes/sfc/cpu/timing.cpp
+++ b/bsnes/sfc/cpu/timing.cpp
@@ -123,6 +123,15 @@ auto CPU::scanline() -> void {
       overclocking.target = clocks * overclock - clocks;
     }
   }
+
+  //handle video frame events from the CPU core to prevent a race condition between
+  //games polling inputs during NMI and the PPU thread not being 100% synchronized.
+  if(vcounter() == ppu.vdisp()) {
+    if(auto device = controllerPort2.device) device->latch();  //light guns
+    synchronizePPU();
+    if(system.fastPPU()) PPUfast::Line::flush();
+    scheduler.leave(Scheduler::Event::Frame);
+  }
 }
 
 auto CPU::aluEdge() -> void {
diff --git a/bsnes/sfc/ppu-fast/ppu.cpp b/bsnes/sfc/ppu-fast/ppu.cpp
index 0d1d8eb4..1be718b3 100644
--- a/bsnes/sfc/ppu-fast/ppu.cpp
+++ b/bsnes/sfc/ppu-fast/ppu.cpp
@@ -118,15 +118,9 @@ auto PPU::scanline() -> void {
   }
 
   if(vcounter() == vdisp()) {
-    if(auto device = controllerPort2.device) device->latch();  //light guns
     if(!io.displayDisable) oamAddressReset();
   }
 
-  if(vcounter() == vdisp()) {  //240
-    Line::flush();
-    scheduler.leave(Scheduler::Event::Frame);
-  }
-
   if(vcounter() == 240) {
     Line::flush();
   }
diff --git a/bsnes/sfc/ppu/main.cpp b/bsnes/sfc/ppu/main.cpp
index 598ac2ba..144dff66 100644
--- a/bsnes/sfc/ppu/main.cpp
+++ b/bsnes/sfc/ppu/main.cpp
@@ -17,14 +17,6 @@ auto PPU::main() -> void {
   window.scanline();
   screen.scanline();
 
-  if(vcounter() == vdisp()) {
-    if(auto device = controllerPort2.device) device->latch();  //light guns
-  }
-
-  if(vcounter() == vdisp()) {  //240
-    scheduler.leave(Scheduler::Event::Frame);
-  }
-
   if(vcounter() > 240) {
     step(hperiod());
     return;
diff --git a/bsnes/target-bsnes/input/hotkeys.cpp b/bsnes/target-bsnes/input/hotkeys.cpp
index 7b6f3e88..1aff93e1 100644
--- a/bsnes/target-bsnes/input/hotkeys.cpp
+++ b/bsnes/target-bsnes/input/hotkeys.cpp
@@ -123,10 +123,9 @@ auto InputManager::bindHotkeys() -> void {
     if(!presentation.frameAdvance.checked()) {
       //start frame advance if not currently frame advancing
       presentation.frameAdvance.setChecked().doActivate();
-    } else {
-      //advance to the next video frame otherwise
-      program.frameAdvanceLock = false;
     }
+    //advance one frame, even if we were currently paused when starting frame advance mode
+    program.frameAdvanceLock = false;
   }));
 
   hotkeys.append(InputHotkey("Increase HD Mode 7").onPress([] {