Merge pull request #1726 from MerryMage/read-write-region

AudioCore: CurrentRegion() -> ReadRegion(), WriteRegion()

src/audio_core/audio_core.cpp

@@ -38,10 +38,10 @@ void Init() {
 
 /// Add DSP address spaces to Process's address space.
 void AddAddressSpace(Kernel::VMManager& address_space) {
-    auto r0_vma = address_space.MapBackingMemory(DSP::HLE::region0_base, reinterpret_cast<u8*>(&DSP::HLE::g_region0), sizeof(DSP::HLE::SharedMemory), Kernel::MemoryState::IO).MoveFrom();
+    auto r0_vma = address_space.MapBackingMemory(DSP::HLE::region0_base, reinterpret_cast<u8*>(&DSP::HLE::g_regions[0]), sizeof(DSP::HLE::SharedMemory), Kernel::MemoryState::IO).MoveFrom();
     address_space.Reprotect(r0_vma, Kernel::VMAPermission::ReadWrite);
 
-    auto r1_vma = address_space.MapBackingMemory(DSP::HLE::region1_base, reinterpret_cast<u8*>(&DSP::HLE::g_region1), sizeof(DSP::HLE::SharedMemory), Kernel::MemoryState::IO).MoveFrom();
+    auto r1_vma = address_space.MapBackingMemory(DSP::HLE::region1_base, reinterpret_cast<u8*>(&DSP::HLE::g_regions[1]), sizeof(DSP::HLE::SharedMemory), Kernel::MemoryState::IO).MoveFrom();
     address_space.Reprotect(r1_vma, Kernel::VMAPermission::ReadWrite);
 }
 

src/audio_core/hle/dsp.cpp

@@ -8,8 +8,32 @@
 namespace DSP {
 namespace HLE {
 
-SharedMemory g_region0;
+std::array<SharedMemory, 2> g_regions;
-SharedMemory g_region1;
+
+static size_t CurrentRegionIndex() {
+    // The region with the higher frame counter is chosen unless there is wraparound.
+    // This function only returns a 0 or 1.
+
+    if (g_regions[0].frame_counter == 0xFFFFu && g_regions[1].frame_counter != 0xFFFEu) {
+        // Wraparound has occured.
+        return 1;
+    }
+
+    if (g_regions[1].frame_counter == 0xFFFFu && g_regions[0].frame_counter != 0xFFFEu) {
+        // Wraparound has occured.
+        return 0;
+    }
+
+    return (g_regions[0].frame_counter > g_regions[1].frame_counter) ? 0 : 1;
+}
+
+static SharedMemory& ReadRegion() {
+    return g_regions[CurrentRegionIndex()];
+}
+
+static SharedMemory& WriteRegion() {
+    return g_regions[1 - CurrentRegionIndex()];
+}
 
 void Init() {
     DSP::HLE::ResetPipes();
@@ -22,21 +46,5 @@ bool Tick() {
     return true;
 }
 
-SharedMemory& CurrentRegion() {
-    // The region with the higher frame counter is chosen unless there is wraparound.
-
-    if (g_region0.frame_counter == 0xFFFFu && g_region1.frame_counter != 0xFFFEu) {
-        // Wraparound has occured.
-        return g_region1;
-    }
-
-    if (g_region1.frame_counter == 0xFFFFu && g_region0.frame_counter != 0xFFFEu) {
-        // Wraparound has occured.
-        return g_region0;
-    }
-
-    return (g_region0.frame_counter > g_region1.frame_counter) ? g_region0 : g_region1;
-}
-
 } // namespace HLE
 } // namespace DSP

src/audio_core/hle/dsp.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <array>
 #include <cstddef>
 #include <type_traits>
 
@@ -30,10 +31,9 @@ namespace HLE {
 struct SharedMemory;
 
 constexpr VAddr region0_base = 0x1FF50000;
-extern SharedMemory g_region0;
-
 constexpr VAddr region1_base = 0x1FF70000;
-extern SharedMemory g_region1;
+
+extern std::array<SharedMemory, 2> g_regions;
 
 /**
  * The DSP is native 16-bit. The DSP also appears to be big-endian. When reading 32-bit numbers from
@@ -535,8 +535,5 @@ void Shutdown();
  */
 bool Tick();
 
-/// Returns a mutable reference to the current region. Current region is selected based on the frame counter.
-SharedMemory& CurrentRegion();
-
 } // namespace HLE
 } // namespace DSP