[sw] Fix some 32-bit assembly issues

I'm not sure that the mismatch between refdef_t and the assembly defines
was a problem (many fields unused), but the main problem was due to
execute permission on the pages: one chunk of asm was in the data
section, and the patched code was not marked as being executable (due to
such a thing not existing when quake was written).

include/QF/render.h

@@ -161,9 +161,9 @@ typedef struct {
 	vec4f_t     viewposition;
 	vec4f_t     viewrotation;
 
-	float		fov_x, fov_y;
-
 	int			ambientlight;
+
+	float		fov_x, fov_y;
 } refdef_t;
 
 // color shifts =============================================================

include/asm_draw.h

@@ -42,14 +42,14 @@
 #define espan_t_v	    4
 #define espan_t_count   8
 #define espan_t_pnext	12
-#define espan_t_size    16
+#define espan_t_size    16	// sizeof(espan_t)
 
 // sspan_t structure
 // !!! if this is changed, it must be changed in d_local.h too !!!
 #define sspan_t_u    	0
 #define sspan_t_v	    4
 #define sspan_t_count   8
-#define sspan_t_size    12
+#define sspan_t_size    12	// sizeof(sspan_t)
 
 // spanpackage_t structure
 // !!! if this is changed, it must be changed in d_polyset.c too !!!
@@ -61,7 +61,7 @@
 #define spanpackage_t_tfrac				20
 #define spanpackage_t_light				24
 #define spanpackage_t_zi				28
-#define spanpackage_t_size				32
+#define spanpackage_t_size				32	// sizeof(spanpackage_t)
 
 // edge_t structure
 // !!! if this is changed, it must be changed in r_shared.h too !!!
@@ -73,7 +73,7 @@
 #define et_nextremove	20
 #define et_nearzi		24
 #define et_owner		28
-#define et_size			32
+#define et_size			32	// sizeof(edge_t)
 
 // surf_t structure
 // !!! if this is changed, it must be changed in r_shared.h too !!!
@@ -93,7 +93,7 @@
 #define st_d_zistepu	48
 #define st_d_zistepv	52
 #define st_pad			56
-#define st_size			64
+#define st_size			64	// sizeof (surf_t)
 
 // clipplane_t structure
 // !!! if this is changed, it must be changed in r_local.h too !!!
@@ -103,18 +103,18 @@
 #define cp_leftedge		20
 #define cp_rightedge	21
 #define cp_reserved		22
-#define cp_size			24
+#define cp_size			24	// sizeof (clipplane_t)
 
 // medge_t structure
 // !!! if this is changed, it must be changed in model.h too !!!
 #define me_v				0
 #define me_cachededgeoffset	8
-#define me_size				12
+#define me_size				12	// sizeof (medge_t)
 
 // mvertex_t structure
 // !!! if this is changed, it must be changed in model.h too !!!
 #define mv_position		0
-#define mv_size			12
+#define mv_size			12	// sizeof (mvertex_t)
 
 // refdef_t structure
 // !!! if this is changed, it must be changed in render.h too !!!
@@ -138,10 +138,12 @@
 #define rd_horizontalFieldOfView	100
 #define rd_xOrigin					104
 #define rd_yOrigin					108
-#define rd_vieworg					112
-#define rd_viewangles				124
-#define rd_ambientlight				136
-#define rd_size						140
+#define rd_viewposition				112
+#define rd_viewrotation				128
+#define rd_ambientlight				144
+#defin	rd_fov_x					148
+#defin	rd_fov_y					152
+#define rd_size						156	// sizeof (refdef_t)
 
 // mtriangle_t structure
 // !!! if this is changed, it must be changed in model.h too !!!

include/d_local.h

@@ -59,8 +59,7 @@ typedef struct surfcache_s
 } surfcache_t;
 
 // !!! if this is changed, it must be changed in asm_draw.h too !!!
-typedef struct sspan_s
-{
+typedef struct sspan_s {
 	int				u, v, count;
 } sspan_t;
 

include/r_local.h

@@ -98,8 +98,7 @@ extern float	cl_wateralpha;
 #define	DIST_NOT_SET	98765
 
 // !!! if this is changed, it must be changed in asm_draw.h too !!!
-typedef struct clipplane_s
-{
+typedef struct clipplane_s {
 	vec3_t		normal;
 	float		dist;
 	struct		clipplane_s	*next;

include/r_shared.h

@@ -81,16 +81,14 @@ extern	struct entity_s		*currententity;
 #define	MAXSPANS			3000
 
 // !!! if this is changed, it must be changed in asm_draw.h too !!!
-typedef struct espan_s
-{
+typedef struct espan_s {
 	int				u, v, count;
 	struct espan_s	*pnext;
 } espan_t;
 
 // FIXME: compress, make a union if that will help
 // insubmodel is only 1, flags is fewer than 32, spanstate could be a byte
-typedef struct surf_s
-{
+typedef struct surf_s {
 	struct surf_s	*next;			// active surface stack in r_edge.c
 	struct surf_s	*prev;			// used in r_edge.c for active surf stack
 	struct espan_s	*spans;			// pointer to linked list of spans to draw

libs/util/sys.c

@@ -437,7 +437,7 @@ Sys_MakeCodeWriteable (uintptr_t startaddr, size_t length)
 	DWORD       flOldProtect;
 
 	if (!VirtualProtect
-		((LPVOID) startaddr, length, PAGE_READWRITE, &flOldProtect))
+		((LPVOID) startaddr, length, PAGE_EXECUTE_READWRITE, &flOldProtect))
 		Sys_Error ("Protection change failed");
 #else
 # ifdef HAVE_MPROTECT

libs/video/renderer/sw/sw_rvarsa.S

@@ -76,6 +76,7 @@ C(r_single_cw):	.long	0
 .globl	C(r_bmodelactive)
 C(r_bmodelactive):		.long	0
 
+	.text
 .global C(R_InitVars)
 C(R_InitVars):
 	movl	C(ceil_cw), %eax