diff --git a/core/hw/sh4/dyna/ssa.h b/core/hw/sh4/dyna/ssa.h
index 0252c956a..523230b8d 100644
--- a/core/hw/sh4/dyna/ssa.h
+++ b/core/hw/sh4/dyna/ssa.h
@@ -37,12 +37,14 @@ public:
 	{
 		AddVersionPass();
 #if DEBUG
-			printf("BEFORE\n");
-			PrintBlock();
+		printf("BEFORE\n");
+		PrintBlock();
 #endif
 
 		ConstPropPass();
-		WriteAfterWritePass();
+		// This should only be done for ram/vram/aram access
+		// Disabled for now and probably not worth the trouble
+		//WriteAfterWritePass();
 		DeadCodeRemovalPass();
 		SimplifyExpressionPass();
 		CombineShiftsPass();
@@ -170,7 +172,34 @@ private:
 			if (op.op != shop_fmac && op.op != shop_adc)
 				ConstPropOperand(op.rs3);
 
-			if (op.op == shop_readm || op.op == shop_writem)
+			if (op.op == shop_ifb)
+			{
+				constprop_values.clear();
+			}
+			else if (op.op == shop_sync_sr)
+			{
+				for (auto it = constprop_values.begin(); it != constprop_values.end(); )
+				{
+					Sh4RegType reg = it->first.get_reg();
+					if (reg == reg_sr_status || reg == reg_old_sr_status || (reg >= reg_r0 && reg <= reg_r7)
+							|| (reg >= reg_r0_Bank && reg <= reg_r7_Bank))
+						it = constprop_values.erase(it);
+					else
+						it++;
+				}
+			}
+			else if (op.op == shop_sync_fpscr)
+			{
+				for (auto it = constprop_values.begin(); it != constprop_values.end(); )
+				{
+					Sh4RegType reg = it->first.get_reg();
+					if (reg == reg_fpscr || reg == reg_old_fpscr || (reg >= reg_fr_0 && reg <= reg_xf_15))
+						it = constprop_values.erase(it);
+					else
+						it++;
+				}
+			}
+			else if (op.op == shop_readm || op.op == shop_writem)
 			{
 				if (op.rs1.is_imm())
 				{
diff --git a/core/nullDC.cpp b/core/nullDC.cpp
index 7dceaf2b1..7218173b4 100755
--- a/core/nullDC.cpp
+++ b/core/nullDC.cpp
@@ -158,8 +158,10 @@ void LoadSpecialSettings()
 			|| !strncmp("T40204D", reios_product_number, 7)
 			// Skies of Arcadia
 			|| !strncmp("MK-51052", reios_product_number, 8)
-			// Flag to Flag
-			|| !strncmp("MK-51007", reios_product_number, 8))
+			// Flag to Flag (US)
+			|| !strncmp("MK-51007", reios_product_number, 8)
+			// Super Speed Racing (JP)
+			|| !strncmp("HDR-0013", reios_product_number, 8))
 	{
 		settings.rend.RenderToTextureBuffer = 1;
 		rtt_to_buffer_game = true;
diff --git a/core/rec-x64/rec_x64.cpp b/core/rec-x64/rec_x64.cpp
index 59349d5f2..b315d18ff 100644
--- a/core/rec-x64/rec_x64.cpp
+++ b/core/rec-x64/rec_x64.cpp
@@ -948,9 +948,17 @@ public:
 			case shop_xtrct:
 				{
 					Xbyak::Reg32 rd = regalloc.MapRegister(op.rd);
-					Xbyak::Reg32 rs1 = regalloc.MapRegister(op.rs1);
-					Xbyak::Reg32 rs2 = regalloc.MapRegister(op.rs2);
-					if (regalloc.mapg(op.rd) == regalloc.mapg(op.rs2))
+					Xbyak::Reg32 rs1 = ecx;
+					if (op.rs1.is_reg())
+						rs1 = regalloc.MapRegister(op.rs1);
+					else
+						mov(rs1, op.rs1.imm_value());
+					Xbyak::Reg32 rs2 = eax;
+					if (op.rs2.is_reg())
+						rs2 = regalloc.MapRegister(op.rs2);
+					else
+						mov(rs2, op.rs2.imm_value());
+					if (rd == rs2)
 					{
 						shl(rd, 16);
 						mov(eax, rs1);
@@ -958,7 +966,7 @@ public:
 						or_(rd, eax);
 						break;
 					}
-					else if (regalloc.mapg(op.rd) != regalloc.mapg(op.rs1))
+					else if (rd != rs1)
 					{
 						mov(rd, rs1);
 					}
@@ -1693,7 +1701,7 @@ private:
 					mov(dword[rax], op.rs2._imm);
 				else
 				{
-					mov(rcx, (uintptr_t)op.rd.reg_ptr());
+					mov(rcx, (uintptr_t)op.rs2.reg_ptr());
 					mov(ecx, dword[rcx]);
 					mov(dword[rax], ecx);
 				}
@@ -1711,7 +1719,7 @@ private:
 				else
 #endif
 				{
-					mov(rcx, (uintptr_t)op.rd.reg_ptr());
+					mov(rcx, (uintptr_t)op.rs2.reg_ptr());
 					mov(rcx, qword[rcx]);
 					mov(qword[rax], rcx);
 				}