diff --git a/src/basicinlines.h b/src/basicinlines.h
index 488cdf5526..8492572818 100644
--- a/src/basicinlines.h
+++ b/src/basicinlines.h
@@ -177,12 +177,3 @@ static inline SDWORD DivScale30 (SDWORD a, SDWORD b) { return (SDWORD)(((SQWORD)
 static inline SDWORD DivScale31 (SDWORD a, SDWORD b) { return (SDWORD)(((SQWORD)a << 31) / b); }
 static inline SDWORD DivScale32 (SDWORD a, SDWORD b) { return (SDWORD)(((SQWORD)a << 32) / b); }
 
-static __forceinline void clearbufshort (void *buff, unsigned int count, WORD clear)
-{
-	SWORD *b2 = (SWORD *)buff;
-	for (unsigned int i = 0; i != count; ++i)
-	{
-		b2[i] = clear;
-	}
-}
-
diff --git a/src/g_shared/a_lightning.cpp b/src/g_shared/a_lightning.cpp
index 3f44f2fddd..bbc6638123 100644
--- a/src/g_shared/a_lightning.cpp
+++ b/src/g_shared/a_lightning.cpp
@@ -23,7 +23,7 @@ DLightningThinker::DLightningThinker ()
 	NextLightningFlash = ((pr_lightning()&15)+5)*35; // don't flash at level start
 
 	LightningLightLevels.Resize(numsectors);
-	clearbufshort(&LightningLightLevels[0], numsectors, SHRT_MAX);
+	fillshort(&LightningLightLevels[0], numsectors, SHRT_MAX);
 }
 
 DLightningThinker::~DLightningThinker ()
@@ -87,7 +87,7 @@ void DLightningThinker::LightningFlash ()
 					tempSec->SetLightLevel(LightningLightLevels[j]);
 				}
 			}
-			clearbufshort(&LightningLightLevels[0], numsectors, SHRT_MAX);
+			fillshort(&LightningLightLevels[0], numsectors, SHRT_MAX);
 			level.flags &= ~LEVEL_SWAPSKIES;
 		}
 		return;
diff --git a/src/gccinlines.h b/src/gccinlines.h
index 54a2448c70..eac1f3e6fb 100644
--- a/src/gccinlines.h
+++ b/src/gccinlines.h
@@ -290,16 +290,3 @@ static inline SDWORD DivScale32 (SDWORD a, SDWORD b)
 		: "cc");
 	return result;
 }
-
-static inline void clearbufshort (void *buff, unsigned int count, WORD clear)
-{
-	asm volatile
-		("shr $1,%%ecx\n\t"
-		 "rep stosl\n\t"
-		 "adc %%ecx,%%ecx\n\t"
-		 "rep stosw"
-		:"=D" (buff), "=c" (count)
-		:"D" (buff), "c" (count), "a" (clear|(clear<<16))
-		:"cc");
-}
-
diff --git a/src/m_fixed.h b/src/m_fixed.h
index 4719ac4680..33d339608a 100644
--- a/src/m_fixed.h
+++ b/src/m_fixed.h
@@ -1,11 +1,3 @@
-// "Build Engine & Tools" Copyright (c) 1993-1997 Ken Silverman
-// Ken Silverman's official web site: "http://www.advsys.net/ken"
-// See the included license file "BUILDLIC.TXT" for license info.
-//
-// This file is based on pragmas.h from Ken Silverman's original Build
-// source code release and contains routines that were originally
-// inline assembly but are not now.
-
 #ifndef __M_FIXED__
 #define __M_FIXED__
 
@@ -20,64 +12,25 @@
 #include "basicinlines.h"
 #endif
 
-#include "xs_Float.h"
-
-#define MAKESAFEDIVSCALE(x) \
-	inline SDWORD SafeDivScale##x (SDWORD a, SDWORD b) \
-	{ \
-		if ((DWORD)abs(a) >> (31-x) >= (DWORD)abs (b)) \
-			return (a^b)<0 ? FIXED_MIN : FIXED_MAX; \
-		return DivScale##x (a, b); \
-	}
-
-MAKESAFEDIVSCALE(1)
-MAKESAFEDIVSCALE(2)
-MAKESAFEDIVSCALE(3)
-MAKESAFEDIVSCALE(4)
-MAKESAFEDIVSCALE(5)
-MAKESAFEDIVSCALE(6)
-MAKESAFEDIVSCALE(7)
-MAKESAFEDIVSCALE(8)
-MAKESAFEDIVSCALE(9)
-MAKESAFEDIVSCALE(10)
-MAKESAFEDIVSCALE(11)
-MAKESAFEDIVSCALE(12)
-MAKESAFEDIVSCALE(13)
-MAKESAFEDIVSCALE(14)
-MAKESAFEDIVSCALE(15)
-MAKESAFEDIVSCALE(16)
-MAKESAFEDIVSCALE(17)
-MAKESAFEDIVSCALE(18)
-MAKESAFEDIVSCALE(19)
-MAKESAFEDIVSCALE(20)
-MAKESAFEDIVSCALE(21)
-MAKESAFEDIVSCALE(22)
-MAKESAFEDIVSCALE(23)
-MAKESAFEDIVSCALE(24)
-MAKESAFEDIVSCALE(25)
-MAKESAFEDIVSCALE(26)
-MAKESAFEDIVSCALE(27)
-MAKESAFEDIVSCALE(28)
-MAKESAFEDIVSCALE(29)
-MAKESAFEDIVSCALE(30)
-#undef MAKESAFEDIVSCALE
-
-inline SDWORD SafeDivScale31 (SDWORD a, SDWORD b)
+__forceinline void fillshort(void *buff, unsigned int count, WORD clear)
 {
-	if ((DWORD)abs(a) >= (DWORD)abs (b))
-		return (a^b)<0 ? FIXED_MIN : FIXED_MAX;
-	return DivScale31 (a, b);
+	SWORD *b2 = (SWORD *)buff;
+	for (unsigned int i = 0; i != count; ++i)
+	{
+		b2[i] = clear;
+	}
 }
 
-inline SDWORD SafeDivScale32 (SDWORD a, SDWORD b)
-{
-	if ((DWORD)abs(a) >= (DWORD)abs (b) >> 1)
-		return (a^b)<0 ? FIXED_MIN : FIXED_MAX;
-	return DivScale32 (a, b);
+#include "xs_Float.h"
+
+inline SDWORD FixedDiv (SDWORD a, SDWORD b) 
+{ 
+	if ((DWORD)abs(a) >> (31-16) >= (DWORD)abs (b)) 
+		return (a^b)<0 ? FIXED_MIN : FIXED_MAX; 
+	return DivScale16 (a, b); 
 }
 
 #define FixedMul MulScale16
-#define FixedDiv SafeDivScale16
 
 inline fixed_t FloatToFixed(double f)
 {
diff --git a/src/mscinlines.h b/src/mscinlines.h
index 1aded4e7b7..6af2da1de7 100644
--- a/src/mscinlines.h
+++ b/src/mscinlines.h
@@ -321,13 +321,4 @@ __forceinline SDWORD DivScale32 (SDWORD a, SDWORD b)
 	__asm idiv b
 }
 
-__forceinline void clearbufshort (void *buff, unsigned int count, WORD clear)
-{
-	SWORD *b2 = (SWORD *)buff;
-	for (unsigned int i = 0; i != count; ++i)
-	{
-		b2[i] = clear;
-	}
-}
-
 #pragma warning (default: 4035)
diff --git a/src/p_effect.cpp b/src/p_effect.cpp
index 42e82d7405..827a457ee2 100644
--- a/src/p_effect.cpp
+++ b/src/p_effect.cpp
@@ -198,7 +198,7 @@ void P_FindParticleSubsectors ()
 		ParticlesInSubsec.Reserve (numsubsectors - ParticlesInSubsec.Size());
 	}
 
-	clearbufshort (&ParticlesInSubsec[0], numsubsectors, NO_PARTICLE);
+	fillshort (&ParticlesInSubsec[0], numsubsectors, NO_PARTICLE);
 
 	if (!r_particles)
 	{
diff --git a/src/r_bsp.cpp b/src/r_bsp.cpp
index bb076d72f5..230e16dccf 100644
--- a/src/r_bsp.cpp
+++ b/src/r_bsp.cpp
@@ -740,8 +740,8 @@ void R_AddLine (seg_t *line)
 	if (line->linedef->special == Line_Horizon)
 	{
 		// Be aware: Line_Horizon does not work properly with sloped planes
-		clearbufshort (walltop+WallC.sx1, WallC.sx2 - WallC.sx1, centery);
-		clearbufshort (wallbottom+WallC.sx1, WallC.sx2 - WallC.sx1, centery);
+		fillshort (walltop+WallC.sx1, WallC.sx2 - WallC.sx1, centery);
+		fillshort (wallbottom+WallC.sx1, WallC.sx2 - WallC.sx1, centery);
 	}
 	else
 	{
diff --git a/src/r_draw.cpp b/src/r_draw.cpp
index 766ad8d7aa..b23bf40818 100644
--- a/src/r_draw.cpp
+++ b/src/r_draw.cpp
@@ -1641,7 +1641,7 @@ namespace swrenderer
 
 		if (b2 > t2)
 		{
-			clearbufshort(spanend + t2, b2 - t2, x);
+			fillshort(spanend + t2, b2 - t2, x);
 		}
 
 		R_SetColorMapLight(basecolormap, (float)light, wallshade);
@@ -1668,7 +1668,7 @@ namespace swrenderer
 				if (b1 > b2) b2 = b1;
 				if (t2 < b2)
 				{
-					clearbufshort(spanend + t2, b2 - t2, x);
+					fillshort(spanend + t2, b2 - t2, x);
 				}
 				rcolormap = lcolormap;
 				R_SetColorMapLight(basecolormap, (float)light, wallshade);
diff --git a/src/r_main.cpp b/src/r_main.cpp
index 543b7cd59a..e79800e49f 100644
--- a/src/r_main.cpp
+++ b/src/r_main.cpp
@@ -377,7 +377,7 @@ void R_SWRSetWindow(int windowSize, int fullWidth, int fullHeight, int stHeight,
 	pspritexiscale = 1 / pspritexscale;
 
 	// thing clipping
-	clearbufshort (screenheightarray, viewwidth, (short)viewheight);
+	fillshort (screenheightarray, viewwidth, (short)viewheight);
 
 	R_InitTextureMapping ();
 
@@ -400,7 +400,7 @@ void R_InitRenderer()
 {
 	atterm(R_ShutdownRenderer);
 	// viewwidth / viewheight are set by the defaults
-	clearbufshort (zeroarray, MAXWIDTH, 0);
+	fillshort (zeroarray, MAXWIDTH, 0);
 
 	R_InitPlanes ();
 	R_InitShadeMaps();
diff --git a/src/r_plane.cpp b/src/r_plane.cpp
index 3769dda061..f8893dcd75 100644
--- a/src/r_plane.cpp
+++ b/src/r_plane.cpp
@@ -328,9 +328,9 @@ void R_ClearPlanes (bool fullclear)
 		}
 
 		// opening / clipping determination
-		clearbufshort (floorclip, viewwidth, viewheight);
+		fillshort (floorclip, viewwidth, viewheight);
 		// [RH] clip ceiling to console bottom
-		clearbufshort (ceilingclip, viewwidth,
+		fillshort (ceilingclip, viewwidth,
 			!screen->Accel2D && ConBottom > viewwindowy && !bRenderingToCanvas
 			? (ConBottom - viewwindowy) : 0);
 
@@ -503,7 +503,7 @@ visplane_t *R_FindPlane (const secplane_t &height, FTextureID picnum, int lightl
 	check->MirrorFlags = MirrorFlags;
 	check->CurrentSkybox = CurrentSkybox;
 
-	clearbufshort (check->top, viewwidth, 0x7fff);
+	fillshort (check->top, viewwidth, 0x7fff);
 
 	return check;
 }
@@ -588,7 +588,7 @@ visplane_t *R_CheckPlane (visplane_t *pl, int start, int stop)
 		pl = new_pl;
 		pl->left = start;
 		pl->right = stop;
-		clearbufshort (pl->top, viewwidth, 0x7fff);
+		fillshort (pl->top, viewwidth, 0x7fff);
 	}
 	return pl;
 }
@@ -1816,7 +1816,7 @@ void R_MapVisPlane (visplane_t *pl, void (*mapfunc)(int y, int x1))
 
 	if (b2 > t2)
 	{
-		clearbufshort (spanend+t2, b2-t2, x);
+		fillshort (spanend+t2, b2-t2, x);
 	}
 
 	for (--x; x >= pl->left; --x)
diff --git a/src/r_segs.cpp b/src/r_segs.cpp
index efc894fc29..c24e7f7190 100644
--- a/src/r_segs.cpp
+++ b/src/r_segs.cpp
@@ -531,7 +531,7 @@ clearfog:
 		}
 		else
 		{
-			clearbufshort(openings + ds->sprtopclip - ds->x1 + x1, x2 - x1, viewheight);
+			fillshort(openings + ds->sprtopclip - ds->x1 + x1, x2 - x1, viewheight);
 		}
 	}
 	return;
@@ -1881,8 +1881,8 @@ void R_RenderSegLoop ()
 				call_wallscan(x1, x2, walltop, wallbottom, swall, lwall, yscale, false);
 			}
 		}
-		clearbufshort (ceilingclip+x1, x2-x1, viewheight);
-		clearbufshort (floorclip+x1, x2-x1, 0xffff);
+		fillshort (ceilingclip+x1, x2-x1, viewheight);
+		fillshort (floorclip+x1, x2-x1, 0xffff);
 	}
 	else
 	{ // two sided line
@@ -2405,7 +2405,7 @@ void R_StoreWallRange (int start, int stop)
 	{
 		ds_p->sprtopclip = R_NewOpening (stop - start);
 		ds_p->sprbottomclip = R_NewOpening (stop - start);
-		clearbufshort (openings + ds_p->sprtopclip, stop-start, viewheight);
+		fillshort (openings + ds_p->sprtopclip, stop-start, viewheight);
 		memset (openings + ds_p->sprbottomclip, -1, (stop-start)*sizeof(short));
 		ds_p->silhouette = SIL_BOTH;
 	}
@@ -2445,7 +2445,7 @@ void R_StoreWallRange (int start, int stop)
 			if (doorclosed || (rw_backfz1 >= rw_frontcz1 && rw_backfz2 >= rw_frontcz2))
 			{						// killough 1/17/98, 2/8/98
 				ds_p->sprtopclip = R_NewOpening (stop - start);
-				clearbufshort (openings + ds_p->sprtopclip, stop - start, viewheight);
+				fillshort (openings + ds_p->sprtopclip, stop - start, viewheight);
 				ds_p->silhouette |= SIL_TOP;
 			}
 		}
@@ -2666,7 +2666,7 @@ int WallMostAny(short *mostbuf, double z1, double z2, const FWallCoords *wallc)
 	}
 	else if (y1 > viewheight && y2 > viewheight) // entire line is below screen
 	{
-		clearbufshort(&mostbuf[wallc->sx1], wallc->sx2 - wallc->sx1, viewheight);
+		fillshort(&mostbuf[wallc->sx1], wallc->sx2 - wallc->sx1, viewheight);
 		return 12;
 	}
 
diff --git a/src/r_things.cpp b/src/r_things.cpp
index f5c75f012d..0a9d74c204 100644
--- a/src/r_things.cpp
+++ b/src/r_things.cpp
@@ -2481,11 +2481,11 @@ void R_DrawSprite (vissprite_t *spr)
 		// for R_DrawVisVoxel().
 		if (x1 > 0)
 		{
-			clearbufshort(cliptop, x1, viewheight);
+			fillshort(cliptop, x1, viewheight);
 		}
 		if (x2 < viewwidth - 1)
 		{
-			clearbufshort(cliptop + x2, viewwidth - x2, viewheight);
+			fillshort(cliptop + x2, viewwidth - x2, viewheight);
 		}
 		int minvoxely = spr->gzt <= hzt ? 0 : xs_RoundToInt((spr->gzt - hzt) / spr->yscale);
 		int maxvoxely = spr->gzb > hzb ? INT_MAX : xs_RoundToInt((spr->gzt - hzb) / spr->yscale);
diff --git a/src/v_draw.cpp b/src/v_draw.cpp
index 5c10406bf4..a56c63998a 100644
--- a/src/v_draw.cpp
+++ b/src/v_draw.cpp
@@ -236,13 +236,13 @@ void DCanvas::DrawTextureParms(FTexture *img, DrawParms &parms)
 
 		if (bottomclipper[0] != parms.dclip)
 		{
-			clearbufshort(bottomclipper, screen->GetWidth(), (short)parms.dclip);
+			fillshort(bottomclipper, screen->GetWidth(), (short)parms.dclip);
 		}
 		if (parms.uclip != 0)
 		{
 			if (topclipper[0] != parms.uclip)
 			{
-				clearbufshort(topclipper, screen->GetWidth(), (short)parms.uclip);
+				fillshort(topclipper, screen->GetWidth(), (short)parms.uclip);
 			}
 			mceilingclip = topclipper;
 		}