diff --git a/src/experiments/nanojpeg/UDIS86.hpp b/src/experiments/nanojpeg/UDIS86.hpp
index a6a08fed..e4f2e4dc 100644
--- a/src/experiments/nanojpeg/UDIS86.hpp
+++ b/src/experiments/nanojpeg/UDIS86.hpp
@@ -48,48 +48,6 @@ public:
 	 * @returns \c true if a new instruction could be retrieved, \c false if the object has expired
 	 */
 	inline bool fetchNextInstruction() { return (ud_disassemble(&ud_obj) > 0); }
-	/**
-	 * Returns the FailBochs equivalent to a UDIS86 GPR identifier.
-	 * Attention: this only returns either 32-bit or 64-bit registers, no general IDs
-	 * @param udisReg the udis86 GPR ID
-	 * @returns the FailBochs GPR ID, usable with the BochsRegisterManager class
-	 */
-	static inline fail::GPRegisterId udisGPRToFailBochsGPR(ud_type_t udisReg)
-	{
-		#define REG_CASE(REG) case UD_R_##REG: return fail::RID_##REG
-			switch (udisReg) {
-		#if BX_SUPPORT_X86_64 // 64 bit register id's:
-			REG_CASE(RAX);
-			REG_CASE(RCX);
-			REG_CASE(RDX);
-			REG_CASE(RBX);
-			REG_CASE(RSP);
-			REG_CASE(RBP);
-			REG_CASE(RSI);
-			REG_CASE(RDI);
-			REG_CASE(R8);
-			REG_CASE(R9);
-			REG_CASE(R10);
-			REG_CASE(R11);
-			REG_CASE(R12);
-			REG_CASE(R13);
-			REG_CASE(R14);
-			REG_CASE(R15);
-		#else
-			REG_CASE(EAX);
-			REG_CASE(ECX);
-			REG_CASE(EDX);
-			REG_CASE(EBX);
-			REG_CASE(ESP);
-			REG_CASE(EBP);
-			REG_CASE(ESI);
-			REG_CASE(EDI);
-		#endif
-			default:
-				return fail::RID_LAST_GP_ID;
-			}
-		#undef REG_CASE
-	}
 };
 
 #endif // __UDIS86_HPP__
diff --git a/src/experiments/nanojpeg/udis86_helper.cc b/src/experiments/nanojpeg/udis86_helper.cc
index 21ab3bd8..58ea44cf 100644
--- a/src/experiments/nanojpeg/udis86_helper.cc
+++ b/src/experiments/nanojpeg/udis86_helper.cc
@@ -209,6 +209,55 @@ Udis86Helper::typeToString(ud_type type)
 }
 #undef CASE
 
+fail::GPRegisterId
+Udis86Helper::udisGPRToFailBochsGPR(ud_type_t udisReg, uint64_t& bitmask)
+{
+#define REG_CASE(UDREG, FAILREG, BITMASK) case UD_R_##UDREG: bitmask = BITMASK; return fail::RID_##FAILREG;
+	switch (udisReg) {
+#if BX_SUPPORT_X86_64 // 64 bit register id's:
+	// TODO
+#else
+	// 8 bit GPRs
+	REG_CASE(AL, EAX, 0xff)
+	REG_CASE(BL, EBX, 0xff)
+	REG_CASE(CL, ECX, 0xff)
+	REG_CASE(DL, EDX, 0xff)
+	REG_CASE(SPL, ESP, 0xff)
+	REG_CASE(BPL, EBP, 0xff)
+	REG_CASE(SIL, ESI, 0xff)
+	REG_CASE(DIL, EDI, 0xff)
+	// (R8B-R15B)
+	REG_CASE(AH, EAX, 0xff00)
+	REG_CASE(BH, EBX, 0xff00)
+	REG_CASE(CH, ECX, 0xff00)
+	REG_CASE(DH, EDX, 0xff00)
+	// 16 bit GPRs
+	REG_CASE(AX, EAX, 0xffff)
+	REG_CASE(BX, EBX, 0xffff)
+	REG_CASE(CX, ECX, 0xffff)
+	REG_CASE(DX, EDX, 0xffff)
+	REG_CASE(SP, ESP, 0xffff)
+	REG_CASE(BP, EBP, 0xffff)
+	REG_CASE(SI, ESI, 0xffff)
+	REG_CASE(DI, EDI, 0xffff)
+	// (R8W-R15W)
+	// 32 bit GPRs
+	REG_CASE(EAX, EAX, 0xffffffff)
+	REG_CASE(EBX, EBX, 0xffffffff)
+	REG_CASE(ECX, ECX, 0xffffffff)
+	REG_CASE(EDX, EDX, 0xffffffff)
+	REG_CASE(ESP, ESP, 0xffffffff)
+	REG_CASE(EBP, EBP, 0xffffffff)
+	REG_CASE(ESI, ESI, 0xffffffff)
+	REG_CASE(EDI, EDI, 0xffffffff)
+	// missing: segment, control, debug, mmx, x86, xmm registers, EIP
+#endif
+	default:
+		return fail::RID_LAST_GP_ID;
+	}
+#undef REG_CASE
+}
+
 void Udis86Helper::initOpcodeModMap()
 {
 	// The mentioned operands only include general-purpose registers.
diff --git a/src/experiments/nanojpeg/udis86_helper.hpp b/src/experiments/nanojpeg/udis86_helper.hpp
index 810202b9..e0cd8d55 100644
--- a/src/experiments/nanojpeg/udis86_helper.hpp
+++ b/src/experiments/nanojpeg/udis86_helper.hpp
@@ -7,6 +7,8 @@
 #include <utility>
 #include <map>
 
+#include "sal/bochs/BochsRegisterIDs.hpp"
+
 class Udis86Helper {
 public:
 	// types
@@ -48,6 +50,13 @@ public:
 	void inOutRegisters(UDRegisterSet& in, UDRegisterSet& out);
 	char operandTypeToChar(unsigned op);
 	unsigned operandCount();
+	/**
+	 * Returns the FailBochs equivalent to a UDIS86 GPR identifier.
+	 * Attention: this only returns either 32-bit or 64-bit registers, no general IDs
+	 * @param udisReg the udis86 GPR ID
+	 * @returns the FailBochs GPR ID, usable with the BochsRegisterManager class
+	 */
+	static fail::GPRegisterId udisGPRToFailBochsGPR(ud_type_t udisReg, uint64_t& bitmask);
 	static char const * mnemonicToString(unsigned mnemonic);
 	static char const * typeToString(ud_type type);
 };