diff --git a/SheepShaver/src/Unix/main_unix.cpp b/SheepShaver/src/Unix/main_unix.cpp
index d58d5333..ca09cd8d 100644
--- a/SheepShaver/src/Unix/main_unix.cpp
+++ b/SheepShaver/src/Unix/main_unix.cpp
@@ -1536,7 +1536,11 @@ void ClearInterruptFlag(uint32 flag)
 
 void DisableInterrupt(void)
 {
+#if EMULATED_PPC
+	WriteMacInt32(XLM_IRQ_NEST, int32(ReadMacInt32(XLM_IRQ_NEST)) + 1);
+#else
 	atomic_add((int *)XLM_IRQ_NEST, 1);
+#endif
 }
 
 
@@ -1546,7 +1550,11 @@ void DisableInterrupt(void)
 
 void EnableInterrupt(void)
 {
+#if EMULATED_PPC
+	WriteMacInt32(XLM_IRQ_NEST, int32(ReadMacInt32(XLM_IRQ_NEST)) - 1);
+#else
 	atomic_add((int *)XLM_IRQ_NEST, -1);
+#endif
 }
 
 
diff --git a/SheepShaver/src/include/thunks.h b/SheepShaver/src/include/thunks.h
index 960991e6..445e1cae 100644
--- a/SheepShaver/src/include/thunks.h
+++ b/SheepShaver/src/include/thunks.h
@@ -51,8 +51,6 @@ enum {
   NATIVE_GET_IND_RESOURCE,
   NATIVE_GET_1_IND_RESOURCE,
   NATIVE_R_GET_RESOURCE,
-  NATIVE_DISABLE_INTERRUPT,
-  NATIVE_ENABLE_INTERRUPT,
   NATIVE_MAKE_EXECUTABLE,
   NATIVE_CHECK_LOAD_INVOC,
   NATIVE_SYNC_HOOK,
diff --git a/SheepShaver/src/kpx_cpu/sheepshaver_glue.cpp b/SheepShaver/src/kpx_cpu/sheepshaver_glue.cpp
index f218304c..e7f1442e 100644
--- a/SheepShaver/src/kpx_cpu/sheepshaver_glue.cpp
+++ b/SheepShaver/src/kpx_cpu/sheepshaver_glue.cpp
@@ -446,14 +446,6 @@ int sheepshaver_cpu::compile1(codegen_context_t & cg_context)
 			status = COMPILE_CODE_OK;
 			break;
 #endif
-		case NATIVE_DISABLE_INTERRUPT:
-			dg.gen_invoke(DisableInterrupt);
-			status = COMPILE_CODE_OK;
-			break;
-		case NATIVE_ENABLE_INTERRUPT:
-			dg.gen_invoke(EnableInterrupt);
-			status = COMPILE_CODE_OK;
-			break;
 		case NATIVE_BITBLT:
 			dg.gen_load_T0_GPR(3);
 			dg.gen_invoke_T0((void (*)(uint32))NQD_bitblt);
@@ -1068,7 +1060,7 @@ void TriggerInterrupt(void)
 void sheepshaver_cpu::handle_interrupt(void)
 {
 	// Do nothing if interrupts are disabled
-	if (*(int32 *)XLM_IRQ_NEST > 0)
+	if (int32(ReadMacInt32(XLM_IRQ_NEST)) > 0)
 		return;
 
 	// Current interrupt nest level
@@ -1266,12 +1258,6 @@ void sheepshaver_cpu::execute_native_op(uint32 selector)
 		get_resource_callbacks[selector - NATIVE_GET_RESOURCE]();
 		break;
 	}
-	case NATIVE_DISABLE_INTERRUPT:
-		DisableInterrupt();
-		break;
-	case NATIVE_ENABLE_INTERRUPT:
-		EnableInterrupt();
-		break;
 	case NATIVE_MAKE_EXECUTABLE:
 		MakeExecutable(0, (void *)gpr(4), gpr(5));
 		break;
diff --git a/SheepShaver/src/rom_patches.cpp b/SheepShaver/src/rom_patches.cpp
index f59c2ce5..eb13d459 100644
--- a/SheepShaver/src/rom_patches.cpp
+++ b/SheepShaver/src/rom_patches.cpp
@@ -1122,13 +1122,9 @@ static bool patch_68k_emul(void)
 	// Extra routine for 68k emulator start
 	lp = (uint32 *)(ROM_BASE + 0x36f900);
 	*lp++ = htonl(0x7c2903a6);					// mtctr	r1
-#if EMULATED_PPC
-	*lp++ = htonl(NativeOpcode(NATIVE_DISABLE_INTERRUPT));
-#else
 	*lp++ = htonl(0x80200000 + XLM_IRQ_NEST);	// lwz		r1,XLM_IRQ_NEST
 	*lp++ = htonl(0x38210001);					// addi		r1,r1,1
 	*lp++ = htonl(0x90200000 + XLM_IRQ_NEST);	// stw		r1,XLM_IRQ_NEST
-#endif
 	*lp++ = htonl(0x80200000 + XLM_KERNEL_DATA);// lwz		r1,XLM_KERNEL_DATA
 	*lp++ = htonl(0x90c10018);					// stw		r6,0x18(r1)
 	*lp++ = htonl(0x7cc902a6);					// mfctr	r6
@@ -1156,13 +1152,9 @@ static bool patch_68k_emul(void)
 	// Extra routine for Mixed Mode
 	lp = (uint32 *)(ROM_BASE + 0x36fa00);
 	*lp++ = htonl(0x7c2903a6);					// mtctr	r1
-#if EMULATED_PPC
-	*lp++ = htonl(NativeOpcode(NATIVE_DISABLE_INTERRUPT));
-#else
 	*lp++ = htonl(0x80200000 + XLM_IRQ_NEST);	// lwz		r1,XLM_IRQ_NEST
 	*lp++ = htonl(0x38210001);					// addi		r1,r1,1
 	*lp++ = htonl(0x90200000 + XLM_IRQ_NEST);	// stw		r1,XLM_IRQ_NEST
-#endif
 	*lp++ = htonl(0x80200000 + XLM_KERNEL_DATA);// lwz		r1,XLM_KERNEL_DATA
 	*lp++ = htonl(0x90c10018);					// stw		r6,0x18(r1)
 	*lp++ = htonl(0x7cc902a6);					// mfctr	r6
@@ -1190,13 +1182,9 @@ static bool patch_68k_emul(void)
 	// Extra routine for Reset/FC1E opcode
 	lp = (uint32 *)(ROM_BASE + 0x36fb00);
 	*lp++ = htonl(0x7c2903a6);					// mtctr	r1
-#if EMULATED_PPC
-	*lp++ = htonl(NativeOpcode(NATIVE_DISABLE_INTERRUPT));
-#else
 	*lp++ = htonl(0x80200000 + XLM_IRQ_NEST);	// lwz		r1,XLM_IRQ_NEST
 	*lp++ = htonl(0x38210001);					// addi		r1,r1,1
 	*lp++ = htonl(0x90200000 + XLM_IRQ_NEST);	// stw		r1,XLM_IRQ_NEST
-#endif
 	*lp++ = htonl(0x80200000 + XLM_KERNEL_DATA);// lwz		r1,XLM_KERNEL_DATA
 	*lp++ = htonl(0x90c10018);					// stw		r6,0x18(r1)
 	*lp++ = htonl(0x7cc902a6);					// mfctr	r6
@@ -1224,13 +1212,9 @@ static bool patch_68k_emul(void)
 	// Extra routine for FE0A opcode (QuickDraw 3D needs this)
 	lp = (uint32 *)(ROM_BASE + 0x36fc00);
 	*lp++ = htonl(0x7c2903a6);					// mtctr	r1
-#if EMULATED_PPC
-	*lp++ = htonl(NativeOpcode(NATIVE_DISABLE_INTERRUPT));
-#else
 	*lp++ = htonl(0x80200000 + XLM_IRQ_NEST);	// lwz		r1,XLM_IRQ_NEST
 	*lp++ = htonl(0x38210001);					// addi		r1,r1,1
 	*lp++ = htonl(0x90200000 + XLM_IRQ_NEST);	// stw		r1,XLM_IRQ_NEST
-#endif
 	*lp++ = htonl(0x80200000 + XLM_KERNEL_DATA);// lwz		r1,XLM_KERNEL_DATA
 	*lp++ = htonl(0x90c10018);					// stw		r6,0x18(r1)
 	*lp++ = htonl(0x7cc902a6);					// mfctr	r6
@@ -1397,15 +1381,10 @@ static bool patch_nanokernel(void)
 	uint32 npc = (uint32)(lp + 1) - ROM_BASE;
 
 	lp = (uint32 *)(ROM_BASE + 0x318000);
-#if EMULATED_PPC
-	*lp++ = htonl(NativeOpcode(NATIVE_ENABLE_INTERRUPT));
-	*lp = htonl(0x48000000 + ((npc - 0x318004) & 0x03fffffc));	// b		ROM_BASE+0x312c2c
-#else
 	*lp++ = htonl(0x81400000 + XLM_IRQ_NEST);	// lwz	r10,XLM_IRQ_NEST
 	*lp++ = htonl(0x394affff);					// subi	r10,r10,1
 	*lp++ = htonl(0x91400000 + XLM_IRQ_NEST);	// stw	r10,XLM_IRQ_NEST
 	*lp = htonl(0x48000000 + ((npc - 0x31800c) & 0x03fffffc));	// b		ROM_BASE+0x312c2c
-#endif
 
 /*
 	// Disable FE0A/FE06 opcodes
diff --git a/SheepShaver/src/thunks.cpp b/SheepShaver/src/thunks.cpp
index af05e504..b63a2a7f 100644
--- a/SheepShaver/src/thunks.cpp
+++ b/SheepShaver/src/thunks.cpp
@@ -55,8 +55,6 @@ uint32 NativeOpcode(int selector)
 {
 	uint32 opcode;
 	switch (selector) {
-	case NATIVE_DISABLE_INTERRUPT:
-	case NATIVE_ENABLE_INTERRUPT:
 	case NATIVE_CHECK_LOAD_INVOC:
 		opcode = POWERPC_NATIVE_OP(0, selector);
 		break;