diff --git a/src/cpu/core_full/op.h b/src/cpu/core_full/op.h
index 26057cb6..29f9bc44 100644
--- a/src/cpu/core_full/op.h
+++ b/src/cpu/core_full/op.h
@@ -496,6 +496,19 @@ switch (inst.code.op) {
 			SETFLAGBIT(ZF,false);
 		}
 		break;
+	case O_BSFd:
+		{
+			FILLFLAGS;
+			if (!inst.op1.d) SETFLAGBIT(ZF,true);
+			Bitu count=0;
+			while (count<32) {
+				if ((inst.op1.d>>count) & 1) break;
+				count++;
+			}
+			inst.op1.d=count;
+			SETFLAGBIT(ZF,false);
+		}
+		break;
 	case O_BSRw:
 		{
 			FILLFLAGS;
@@ -509,6 +522,19 @@ switch (inst.code.op) {
 			SETFLAGBIT(ZF,false);
 		}
 		break;
+	case O_BSRd:
+		{
+			FILLFLAGS;
+			if (!inst.op1.d) SETFLAGBIT(ZF,true);
+			Bits count=31;
+			while (count>0) {
+				if ((inst.op1.d>>count) & 1) break;
+				count--;
+			}
+			inst.op1.d=count;
+			SETFLAGBIT(ZF,false);
+		}
+		break;
 	case O_BTw:
 	case O_BTSw:
 	case O_BTCw:
diff --git a/src/cpu/core_full/optable.h b/src/cpu/core_full/optable.h
index 367d46f7..bc6c9908 100644
--- a/src/cpu/core_full/optable.h
+++ b/src/cpu/core_full/optable.h
@@ -668,7 +668,7 @@ static OpCode OpCodeTable[1024]={
 /* 0x3b8 - 0x3bf */
 {0			,0			,0		,0		},{0		,0			,0		,0		},
 {L_MODRM	,0xf		,0		,M_GRP	},{L_MODRM	,O_BTCd		,0		,0		},
-{0			,0			,0		,0		},{0		,0			,0		,0		},
+{L_MODRM	,O_BSFd		,S_Gd	,M_Ed	},{L_MODRM	,O_BSRd		,S_Gd	,M_Ed	},
 {L_MODRM	,0			,S_Gd	,M_Ebx	},{L_MODRM	,0			,S_Gd	,M_Ewx	},
 
 /* 0x3c0 - 0x3cc */
diff --git a/src/cpu/core_full/support.h b/src/cpu/core_full/support.h
index 2d2477de..b5a40f59 100644
--- a/src/cpu/core_full/support.h
+++ b/src/cpu/core_full/support.h
@@ -87,7 +87,7 @@ enum {
 	
 	O_BTw,O_BTSw,O_BTRw,O_BTCw,
 	O_BTd,O_BTSd,O_BTRd,O_BTCd,
-	O_BSFw,O_BSRw,
+	O_BSFw,O_BSRw,O_BSFd,O_BSRd,
 
 	O_BSWAP,
 	O_FPU,