From 5bb0f5c8116366c451a2c171912ae7b9a7427068 Mon Sep 17 00:00:00 2001
From: slash0042 <57612744+slash0042@users.noreply.github.com>
Date: Mon, 27 Jan 2020 21:58:14 -0600
Subject: [PATCH] Libretro: Add support for libnx (#755)

---
 Core/DefaultVideoFilter.cpp | 5 +++--
 Libretro/Makefile           | 9 +++++++++
 Utilities/CRC32.cpp         | 6 +++---
 Utilities/stb_vorbis.cpp    | 2 +-
 4 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/Core/DefaultVideoFilter.cpp b/Core/DefaultVideoFilter.cpp
index aa173024..751d7538 100644
--- a/Core/DefaultVideoFilter.cpp
+++ b/Core/DefaultVideoFilter.cpp
@@ -1,13 +1,14 @@
 #include "stdafx.h"
 #include "DefaultVideoFilter.h"
 #include "EmulationSettings.h"
-#define _USE_MATH_DEFINES
 #include <math.h>
+#define M_PI  3.14159265358979323846264f
 #include <algorithm>
 #include "PPU.h"
 #include "DebugHud.h"
 #include "Console.h"
 
+
 DefaultVideoFilter::DefaultVideoFilter(shared_ptr<Console> console) : BaseVideoFilter(console)
 {
 	InitConversionMatrix(_pictureSettings.Hue, _pictureSettings.Saturation);
@@ -126,4 +127,4 @@ uint32_t DefaultVideoFilter::ApplyScanlineEffect(uint16_t ppuPixel, uint8_t scan
 	uint8_t b = (pixelOutput & 0xFF) * scanlineIntensity / 255;
 
 	return 0xFF000000 | (r << 16) | (g << 8) | b;
-}
\ No newline at end of file
+}
diff --git a/Libretro/Makefile b/Libretro/Makefile
index 611a3489..b521f0c3 100644
--- a/Libretro/Makefile
+++ b/Libretro/Makefile
@@ -163,6 +163,15 @@ else ifeq ($(platform), vita)
    AR = arm-vita-eabi-ar
    CXXFLAGS += -Wl,-q -Wall -O3
   STATIC_LINKING = 1
+# Nintendo Switch (libnx)
+else ifeq ($(platform), libnx)
+   include $(DEVKITPRO)/libnx/switch_rules
+   TARGET := $(TARGET_NAME)_libretro_$(platform).a
+   DEFINES := -DSWITCH=1 -D__SWITCH__ -D_LARGEFILE_SOURCE -DHAVE_LIBNX -D__aarch64__
+   CFLAGS := $(DEFINES) -fPIE -I$(LIBNX)/include/ -ffunction-sections -fdata-sections -ftls-model=local-exec 
+   CFLAGS += -march=armv8-a -mtune=cortex-a57 -mtp=soft -mcpu=cortex-a57+crc+fp+simd -ffast-math
+   CXXFLAGS := $(ASFLAGS) $(CFLAGS)
+   STATIC_LINKING = 1
 # Windows MSVC 2017 all architectures
 else ifneq (,$(findstring windows_msvc2017,$(platform)))
 
diff --git a/Utilities/CRC32.cpp b/Utilities/CRC32.cpp
index d03823c0..88fce9fc 100644
--- a/Utilities/CRC32.cpp
+++ b/Utilities/CRC32.cpp
@@ -16,12 +16,12 @@ extern const uint32_t Crc32Lookup[MaxSlice][256];
 #endif
 
 // define endianess and some integer data types
-#if defined(_MSC_VER) || defined(__MINGW32__)
+#if defined(_MSC_VER) || defined(__MINGW32__) || defined(__aarch64__)
 	// Windows always little endian
 	#define __BYTE_ORDER __LITTLE_ENDIAN
 #else
 	// defines __BYTE_ORDER as __LITTLE_ENDIAN or __BIG_ENDIAN
-	#ifdef __APPLE__
+#if defined(__APPLE__) || defined(HAVE_LIBNX)
 		#include <machine/endian.h>
 	#else
 		#include <endian.h>
@@ -685,4 +685,4 @@ const uint32_t Crc32Lookup[MaxSlice][256] =
 		0x839B5EED,0x2DF3CF7C,0x043B7B8E,0xAA53EA1F,0x57AA126A,0xF9C283FB,0xD00A3709,0x7E62A698,
 		0xF088C1A2,0x5EE05033,0x7728E4C1,0xD9407550,0x24B98D25,0x8AD11CB4,0xA319A846,0x0D7139D7,
 	 }
-};
\ No newline at end of file
+};
diff --git a/Utilities/stb_vorbis.cpp b/Utilities/stb_vorbis.cpp
index 655a737a..b17c63dc 100644
--- a/Utilities/stb_vorbis.cpp
+++ b/Utilities/stb_vorbis.cpp
@@ -224,7 +224,7 @@
    #if defined(_MSC_VER) || defined(__MINGW32__)
       #include <malloc.h>
    #endif
-   #if defined(__linux__) || defined(__linux) || defined(__EMSCRIPTEN__)
+   #if defined(__linux__) || defined(__linux) || defined(__EMSCRIPTEN__) || defined(HAVE_LIBNX)
       #include <alloca.h>
    #endif
 #else // STB_VORBIS_NO_CRT