[EMSCRIPTEN] less workarounds due to fixes in emscripten, enable more optimizations

Makefile.emscripten

@@ -47,16 +47,19 @@ HAVE_FREETYPE = 1
 HAVE_ZLIB = 1
 HAVE_FBO = 1
 WANT_MINIZ = 1
+MEMORY = 67108864
+LTO = 0
+FAST_DOUBLES = 1
 
 ifneq ($(NATIVE_ZLIB),)
    WANT_MINIZ = 0
 endif
 
-libretro ?= -lretro_emscripten
+libretro = libretro_emscripten.bc
 
 LIBS = -lm
 DEFINES = -DHAVE_SCREENSHOTS -DHAVE_NULLAUDIO -DHAVE_BSV_MOVIE -DPACKAGE_VERSION=\"0.9.9.3\"
-LDFLAGS = -L. -static-libgcc -s TOTAL_MEMORY=268435456
+LDFLAGS = -L. -s TOTAL_MEMORY=$(MEMORY)
 
 ifeq ($(SCALER_NO_SIMD), 1)
    DEFINES += -DSCALER_NO_SIMD
@@ -105,8 +108,6 @@ ifeq ($(HAVE_ZLIB), 1)
    endif
 endif
 
-LIBS += $(libretro)
-
 ifeq ($(HAVE_FBO), 1)
    DEFINES += -DHAVE_FBO
 endif
@@ -117,8 +118,17 @@ endif
 
 ifeq ($(DEBUG), 1)
    LDFLAGS += -O0 -g
+   CFLAGS += -O0 -g
 else
-   LDFLAGS += -O2 -ffast-math
+   LDFLAGS += -O2
+   # WARNING: some optimizations can break some cores (ex: LTO breaks tyrquake)
+   ifeq ($(FAST_DOUBLES), 1)
+      LDFLAGS += -s DOUBLE_MODE=0
+   endif
+   ifeq ($(LTO), 1)
+      LDFLAGS += --llvm-lto 3
+   endif
+   CFLAGS += -O2
 endif
 
 CFLAGS += -Wall -Wno-unused-result -Wno-unused-variable -I. -std=gnu99
@@ -127,7 +137,7 @@ all: $(TARGET)
 
 $(TARGET): $(OBJ)
 	@$(if $(Q), $(shell echo echo LD $@),)
-	$(Q)$(LD) -o $@ $(OBJ) $(LIBS) $(LDFLAGS)
+	$(Q)$(LD) -o $@ $(OBJ) $(libretro) $(LIBS) $(LDFLAGS)
 
 %.o: %.c
 	@$(if $(Q), $(shell echo echo CC $<),)

frontend/frontend_emscripten.c

@@ -31,12 +31,33 @@
 
 static bool menuloop;
 
-void mainloop(void)
+static void endloop(void)
+{
+   g_extern.system.shutdown = false;
+   menu_free();
+
+   if (g_extern.config_save_on_exit && *g_extern.config_path)
+      config_save_file(g_extern.config_path);
+
+   if (g_extern.main_is_init)
+      rarch_main_deinit();
+
+   rarch_deinit_msg_queue();
+
+#ifdef PERF_TEST
+   rarch_perf_log();
+#endif
+
+   rarch_main_clear_state();
+
+   exit(0);
+}
+
+static void mainloop(void)
 {
    if (g_extern.system.shutdown)
    {
-      RARCH_ERR("Exit...\n");
-      exit(0);
+      endloop();
    }
    else if (menuloop)
    {

gfx/context/emscriptenegl_ctx.c

@@ -30,14 +30,12 @@
 
 #include <EGL/egl.h>
 #include <EGL/eglext.h>
-#include <GLES/gl.h>
 #include <SDL/SDL.h>
 
 static EGLContext g_egl_ctx;
 static EGLSurface g_egl_surf;
 static EGLDisplay g_egl_dpy;
 static EGLConfig g_config;
-static bool g_quit;
 
 static bool g_inited;
 
@@ -58,12 +56,13 @@ static void gfx_ctx_check_window(bool *quit,
    (void)height;
 
    *resize = false;
-   *quit   = g_quit;
+   *quit   = false;
 }
 
 static void gfx_ctx_swap_buffers(void)
 {
-   eglSwapBuffers(g_egl_dpy, g_egl_surf);
+   // no-op in emscripten, no way to force swap/wait for vsync in browsers
+   //eglSwapBuffers(g_egl_dpy, g_egl_surf);
 }
 
 static void gfx_ctx_set_resize(unsigned width, unsigned height)
@@ -209,7 +208,7 @@ static void gfx_ctx_input_driver(const input_driver_t **input, void **input_data
 {
    *input = NULL;
 
-   if (SDL_Init(SDL_INIT_VIDEO) != 0)
+   if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_NOPARACHUTE) != 0)
       return;
 
    void *sdlinput = input_sdl.init();
@@ -228,7 +227,7 @@ static bool gfx_ctx_has_focus(void)
 
 static gfx_ctx_proc_t gfx_ctx_get_proc_address(const char *symbol)
 {
-   return SDL_GL_GetProcAddress(symbol);
+   return eglGetProcAddress(symbol);
 }
 
 static float gfx_ctx_translate_aspect(unsigned width, unsigned height)

input/sdl_input.c

@@ -24,7 +24,7 @@
 #include "../libretro.h"
 #include "input_common.h"
 
-#if !(SDL_MAJOR_VERSION <= 1 && SDL_MINOR_VERSION <= 2)
+#ifdef EMSCRIPTEN
 #define SDL_GetKeyState SDL_GetKeyboardState
 #endif
 
@@ -232,12 +232,7 @@ static void sdl_poll_mouse(sdl_input_t *sdl)
 
 static void sdl_input_poll(void *data)
 {
-#ifdef EMSCRIPTEN
-   SDL_Event event;
-   while (SDL_PollEvent(&event));
-#else
    SDL_PumpEvents();
-#endif
    sdl_input_t *sdl = (sdl_input_t*)data;
 
    input_joypad_poll(sdl->joypad);