gfxlib2: Control selection of x86 MMX blitters

- added fb.GFX_NO_X86_MMX = &h00000100 constant to fbgfx.bi,
  when passed as flag to SCREEN[RES] disable MMX blitters on x86 32-bit
- added fb.GET_X86_MMX_ENABLED = 18 constant to fbgfx.bi,
  used with ScreenControl to determine if MMX blitters are selected
  If returned value is non-zero, then MMX is enabled.  If zero, then
  MMX is disabled.  All other platforms return zero.
- added fb.SET_X86_MMX_ENABLED = 118 constant to fbgfx.bi,
  used with ScreenControl to specific if MMX blitters should be used.
  Pass non-zero value to enable, and zero value to disable.
  All other platforms ignore this setting
- internal: query the cpu type for MMX capability only when setting the
  graphics mode with SCREEN[RES] or when setting x86 MMX feature with
  ScreenControl fb.SET_X86_MMX_ENABLED function

changelog.txt

@@ -8,6 +8,7 @@ Version 1.20.0
 - emscripten/fbc: don't cast to integer for array indexing (possible regression of behaviour when fixing github #217)
 - github #421: fbc: win32/win64: pass '-fno-ident' to gcc to help prevent identification strings from accumulating in the final binary
 - fbc: internal: rtlMathLongintDIV() decide on signed or unsigned division based on sign instead of exact data type
+- gfxlib2: on x86 32-bit, query the cpu type for MMX capability only when setting the graphics mode with SCREEN[RES] or when setting x86 MMX feature with ScreenControl fb.SET_X86_MMX_ENABLED function
 
 [added]
 - x86_64: optimize SHL MOD INTDIV to use 32-bit operation when result will be converted to long/ulong
@@ -21,6 +22,9 @@ Version 1.20.0
 - gas64: optimizations: enable IR_OPT_ADDRCISC optimizations to use complex addressing (base + offset*multiplier) optimization for indexes (SARG)
 - fbc headers: add ./inc/fberror.bi for runtime library error constants
 - rtlib: ./inc/fbc-int/string.bi - for string descriptor and low level string functions
+- gfxlib2: added fb.GFX_NO_X86_MMX = &h00000100 constant to fbgfx.bi - when passed as flag to SCREEN[RES] disable MMX blitters on x86 32-bit 
+- gfxlib2: added fb.GET_X86_MMX_ENABLED = 18 constant to fbgfx.bi - used with ScreenControl to determine if MMX blitters are selected on x86 32 bit.  If returned value is non-zero, then MMX is enabled.  If zero, then MMX is disabled.  All other platforms return zero.
+- gfxlib2: added fb.SET_X86_MMX_ENABLED = 118 constant to fbgfx.bi - used with ScreenControl to specific if MMX blitters should be used on x86 32-bit.  Pass non-zero value to enable, and zero value to disable.  All other platforms ignore this setting 
 
 [fixed]
 - github #410: give consistent floating point comparisons results involving NaNs.

inc/fbgfx.bi

@@ -48,7 +48,8 @@ namespace FB
 		GFX_SHAPED_WINDOW           = &h00000010, _
 		GFX_ALWAYS_ON_TOP           = &h00000020, _
 		GFX_ALPHA_PRIMITIVES        = &h00000040, _
-		GFX_HIGH_PRIORITY           = &h00000080,_
+		GFX_HIGH_PRIORITY           = &h00000080, _
+		GFX_NO_X86_MMX              = &h00000100, _
 		GFX_SCREEN_EXIT             = &h80000000l
 
 	'' OpenGL options
@@ -85,6 +86,7 @@ namespace FB
 		GET_GL_EXTENSIONS           = 15, _
 		GET_HIGH_PRIORITY           = 16, _
 		GET_SCANLINE_SIZE           = 17, _
+		GET_X86_MMX_ENABLED         = 18, _
 		_
 		GET_GL_COLOR_BITS           = 37, _
 		GET_GL_COLOR_RED_BITS       = 38, _
@@ -124,6 +126,7 @@ namespace FB
 		SET_GL_ACCUM_BLUE_BITS      = 115, _
 		SET_GL_ACCUM_ALPHA_BITS     = 116, _
 		SET_GL_NUM_SAMPLES          = 117, _
+		SET_X86_MMX_ENABLED         = 118, _
 		_
 		SET_GL_2D_MODE              = 150, _
 		SET_GL_SCALE                = 151

src/gfxlib2/fb_gfx.h

@@ -47,6 +47,7 @@ DRIVER_SHAPED_WINDOW    0x00000010    yes  no   yes  no   no
 DRIVER_ALWAYS_ON_TOP    0x00000020    no   no   yes  no   no
 DRIVER_ALPHA_PRIMITIVES 0x00000040    yes  no   no   no   no
 DRIVER_HIGH_PRIORITY    0x00000080    yes  no   yes  no   no
+DRIVER_NO_X86_MMX       0x00000100    yes  no   yes  no   no
 DRIVER_OPENGL_OPTIONS   0x000F0000    no   no   yes  no   no
 HAS_STENCIL_BUFFER      0x00010000    no   no   yes  no   no
 HAS_ACCUMULATION_BUFFER 0x00020000    no   no   yes  no   no
@@ -78,6 +79,7 @@ OPENGL_SUPPORT          0x20000000    no   yes  no   yes  yes
 #define DRIVER_ALWAYS_ON_TOP    0x00000020
 #define DRIVER_ALPHA_PRIMITIVES 0x00000040
 #define DRIVER_HIGH_PRIORITY    0x00000080
+#define DRIVER_NO_X86_MMX       0x00000100
 #define DRIVER_OPENGL_OPTIONS   0x000F0000
 #define HAS_STENCIL_BUFFER      0x00010000
 #define HAS_ACCUMULATION_BUFFER 0x00020000
@@ -156,6 +158,7 @@ OPENGL_SUPPORT          0x20000000    no   yes  no   yes  yes
 #define GET_GL_EXTENSIONS           15
 #define GET_HIGH_PRIORITY           16
 #define GET_SCANLINE_SIZE           17
+#define GET_X86_MMX_ENABLED         18
 
 #define GET_GL_COLOR_BITS           37
 #define GET_GL_COLOR_RED_BITS       38
@@ -195,6 +198,7 @@ OPENGL_SUPPORT          0x20000000    no   yes  no   yes  yes
 #define SET_GL_ACCUM_BLUE_BITS      115
 #define SET_GL_ACCUM_ALPHA_BITS     116
 #define SET_GL_NUM_SAMPLES          117
+#define SET_X86_MMX_ENABLED         118
 
 #define SET_GL_2D_MODE              150
 #define SET_GL_SCALE                151

src/gfxlib2/gfx_control.c

@@ -165,6 +165,11 @@ FBCALL void fb_GfxControl_i( int what, ssize_t *param1, ssize_t *param2, ssize_t
 			res1 = __fb_gfx->scanline_size;
 		break;
 
+	case GET_X86_MMX_ENABLED:
+		if (__fb_gfx)
+			res1 = (__fb_gfx->flags & X86_MMX_ENABLED) ? FB_TRUE : FB_FALSE;
+		break;
+
 	case SET_WINDOW_POS:
 		if ((__fb_gfx) && (__fb_gfx->driver->set_window_pos))
 			__fb_gfx->driver->set_window_pos(*param1, *param2);
@@ -303,6 +308,23 @@ FBCALL void fb_GfxControl_i( int what, ssize_t *param1, ssize_t *param2, ssize_t
 		__fb_gl_params.num_samples = *param1;
 		break;
 
+	case SET_X86_MMX_ENABLED:
+#ifdef HOST_X86
+		if (__fb_gfx) {
+			if (fb_CpuDetect() & 0x800000) {
+				if (*param1) {
+					__fb_gfx->flags |= X86_MMX_ENABLED;
+				} else {
+					__fb_gfx->flags &= ~X86_MMX_ENABLED;
+				}
+			} else {
+				__fb_gfx->flags &= ~X86_MMX_ENABLED;
+			}
+		}
+#endif
+		context->last_target = NULL;
+		break;
+
 	case SET_GL_2D_MODE:
 		/* set the initial 2d mode only; we don't want to
 		   change the active mode in use.  The activie mode

src/gfxlib2/gfx_core.c

@@ -290,8 +290,7 @@ static void *fb_hPixelCpy4(void *dest, const void *src, size_t size)
 void fb_hSetupFuncs(int bpp)
 {
 #ifdef HOST_X86
-	if (fb_CpuDetect() & 0x800000) {
-		__fb_gfx->flags |= X86_MMX_ENABLED;
+	if (__fb_gfx->flags & X86_MMX_ENABLED) {
 		fb_hMemCpy = fb_hMemCpyMMX;
 		fb_hMemSet = fb_hMemSetMMX;
 	} else {

src/gfxlib2/gfx_screen.c

@@ -285,14 +285,26 @@ static int set_mode
         __fb_gfx->event_queue = (EVENT *)malloc(sizeof(EVENT) * MAX_EVENTS);
         __fb_gfx->event_mutex = fb_MutexCreate();
         __fb_color_conv_16to32 = (unsigned int *)malloc(sizeof(int) * 512);
-        if (flags != DRIVER_NULL) {
-			if (flags & DRIVER_ALPHA_PRIMITIVES)
-	        	__fb_gfx->flags |= ALPHA_PRIMITIVES;
-	        if (flags & DRIVER_OPENGL)
-	        	__fb_gfx->flags |= OPENGL_SUPPORT;
-	        if (flags & DRIVER_HIGH_PRIORITY)
-	        	__fb_gfx->flags |= HIGH_PRIORITY;
-	    }
+
+		if (flags != DRIVER_NULL) {
+			if (flags & DRIVER_ALPHA_PRIMITIVES) {
+				__fb_gfx->flags |= ALPHA_PRIMITIVES;
+			}
+			if (flags & DRIVER_OPENGL) {
+				__fb_gfx->flags |= OPENGL_SUPPORT;
+			}
+			if (flags & DRIVER_HIGH_PRIORITY) {
+				__fb_gfx->flags |= HIGH_PRIORITY;
+			}
+		}
+
+#ifdef HOST_X86
+		if (fb_CpuDetect() & 0x800000) {
+			if (!(flags & DRIVER_NO_X86_MMX)) {
+				__fb_gfx->flags |= X86_MMX_ENABLED;
+			}
+		}
+#endif
 
         fb_hSetupFuncs(__fb_gfx->bpp);
         fb_hSetupData();