diff --git a/autotest/autotest.bat b/autotest/autotest.bat
index 0dbf0f6..c18d90d 100644
--- a/autotest/autotest.bat
+++ b/autotest/autotest.bat
@@ -1,5 +1,8 @@
 rem @echo off
 
+@call :test opp_string.cpp
+@if %errorlevel% neq 0 goto :error
+
 @call :test operatoroverload.cpp
 @if %errorlevel% neq 0 goto :error
 
diff --git a/autotest/opp_string.cpp b/autotest/opp_string.cpp
new file mode 100644
index 0000000..8df38de
--- /dev/null
+++ b/autotest/opp_string.cpp
@@ -0,0 +1,96 @@
+#include <opp/string.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <string.h>
+
+static const char HelloWorld[] = "Hello World";
+static const char AndBeyond[] = "And Beyond";
+static const char And[] = "And";
+static const char HelloWorldAndBeyond[] = "Hello World And Beyond";
+
+void test_create(void)
+{
+	string	s1();
+	string	s2(HelloWorld);
+	string	s3(s2);
+	string	s4('a');
+
+	assert(!strcmp(s2.tocstr(), HelloWorld));
+	assert(!strcmp(s3.tocstr(), HelloWorld));
+	assert(s4.size() == 1 && s4[0] == 'a');
+}
+
+void test_concat(void)
+{
+	string	s1();
+	string	s2(HelloWorld);
+	string	s3(AndBeyond);
+
+	string	s4 = s1 + s2;
+	string	s5 = s2 + " " + s3;
+	string	s6 = s2 + " " + AndBeyond;
+
+	assert(!strcmp(s4.tocstr(), HelloWorld));
+	assert(!strcmp(s5.tocstr(), HelloWorldAndBeyond));
+	assert(!strcmp(s6.tocstr(), HelloWorldAndBeyond));	
+}
+
+__noinline void test_find(void)
+{
+	string s1(HelloWorldAndBeyond);
+	string s2(And);
+
+	assert(s1.find(HelloWorld) == 0);
+	assert(s1.find(AndBeyond) == 12);
+	assert(s1.find(And) == 12);
+	assert(s1.find(s2) == 12);
+
+	assert(s1.find(' ') == 5);
+	assert(s1.find(' ', 6) == 11);
+}
+
+void test_assign(void)
+{
+	string	s1(HelloWorld);
+	string	s2(AndBeyond);
+	string	s3;
+	s3 = s1;
+	s3 = s2;
+	s3 = s1;
+	s3 += " ";
+	s3 += s2;
+
+	assert(!strcmp(s3.tocstr(), HelloWorldAndBeyond));
+
+	s3 <<= 12;
+
+	assert(!strcmp(s3.tocstr(), AndBeyond));
+
+	s3 = HelloWorldAndBeyond;
+
+	assert(!strcmp(s3.tocstr(), HelloWorldAndBeyond));
+
+	s3 >>= 11;
+
+	assert(!strcmp(s3.tocstr(), HelloWorld));
+}
+
+int main(void)
+{
+	char * p = new char;	
+	unsigned	avail = heapfree();
+
+	test_create();
+	assert(avail == heapfree());
+
+	test_concat();
+	assert(avail == heapfree());
+
+	test_find();
+	assert(avail == heapfree());
+
+	test_assign();
+	assert(avail == heapfree());
+
+	return 0;
+}
diff --git a/include/opp/string.cpp b/include/opp/string.cpp
index b64136f..f5468d6 100644
--- a/include/opp/string.cpp
+++ b/include/opp/string.cpp
@@ -2,26 +2,53 @@
 #include <string.h>
 #include <stdlib.h>
 
+static inline void smemcpy(char * dp, const char * sp, char s)
+{
+	for(char i=0; i<s; i++)
+		dp[i] = sp[i];
+}
+
 string::string(void) : cstr(nullptr)
 {}
 
 string::string(const string & s)
 {
-	cstr = malloc(strlen(s.cstr) + 1);
-	strcpy(cstr, s.cstr);
+	if (s.cstr)
+	{
+		char l = s.cstr[0];
+		cstr = malloc(l + 2);
+		smemcpy(cstr, s.cstr, l + 2);
+	}
+	else
+		cstr = nullptr;
 }
 
 string::string(const char * s)
 {
-	cstr = malloc(strlen(s) + 1);
-	strcpy(cstr, s);
+	char l = strlen(s);
+	if (l)
+	{
+		cstr = malloc(l + 2);
+		cstr[0] = l;
+		smemcpy(cstr + 1, s, l + 1);
+	}
+	else
+		cstr = nullptr;
 }
 
-string::string(const char * s1, const char * s2)
+string::string(char c)
 {
-	cstr = malloc(strlen(s1) + strlen(s2) + 1);
-	strcpy(cstr, s1);
-	strcat(cstr, s2);
+	cstr = malloc(3);
+	cstr[0] = 1;
+	cstr[1] = c;
+	cstr[2] = 0;
+}
+
+string::string(char l, char * b)
+	: cstr(b)
+{
+	b[0] = l;
+	b[l + 1] = 0;
 }
 
 string::~string(void)
@@ -34,8 +61,14 @@ string & string::operator=(const string & s)
 	if (cstr != s.cstr)	
 	{
 		free(cstr);
-		cstr = malloc(strlen(s.cstr) + 1);
-		strcpy(cstr, s.cstr);
+		if (s.cstr)
+		{
+			char l = s.cstr[0];
+			cstr = malloc(l + 2);
+			smemcpy(cstr, s.cstr, l + 2);
+		}
+		else
+			cstr = nullptr;
 	}
 
 	return *this;
@@ -44,119 +77,433 @@ string & string::operator=(const string & s)
 string & string::operator=(const char * s)
 {
 	free(cstr);
-	cstr = malloc(strlen(s) + 1);
-	strcpy(cstr, s);
+	char l = strlen(s);
+	if (l)
+	{
+		cstr = malloc(l + 2);
+		cstr[0] = l;		
+		smemcpy(cstr + 1, s, l + 1);
+	}
+	else
+		cstr = nullptr;
 
 	return *this;	
 }
 
 string & string::operator+=(const string & s)
 {
-	char * nstr = malloc(strlen(cstr) + strlen(s.cstr) + 1);
-	strcpy(nstr, cstr);
-	strcat(nstr, s.cstr);
-	free(cstr);
-	cstr = nstr;
+	if (s.cstr)
+	{
+		if (cstr)
+		{
+			char l = cstr[0] + s.cstr[0];
+			char * c = malloc(l + 2);
+			c[0] = l;
+			smemcpy(c + 1, cstr + 1, cstr[0]);
+			smemcpy(c + 1 + cstr[0], s.cstr + 1, s.cstr[0] + 1);
+			free(cstr);
+			cstr = c;
+		}
+		else
+		{
+			char l = s.cstr[0];
+			cstr = malloc(l + 2);
+			smemcpy(cstr, s.cstr, l + 2);
+		}
+	}
 	return *this;
 }
 
 string & string::operator+=(const char * s)
 {
-	char * nstr = malloc(strlen(cstr) + strlen(s) + 1);
-	strcpy(nstr, cstr);
-	strcat(nstr, s);
-	free(cstr);
-	cstr = nstr;
+	char sl = strlen(s);
+	if (sl)
+	{
+		if (cstr)
+		{
+			char l = sl + cstr[0];
+			char * c = malloc(l + 2);
+			c[0] = l;
+			smemcpy(c + 1, cstr + 1, cstr[0]);
+			smemcpy(c + 1 + cstr[0], s, sl + 1);
+			free(cstr);
+			cstr = c;
+		}
+		else
+		{
+			cstr = malloc(sl + 2);
+			cstr[0] = sl;
+			smemcpy(cstr + 1, s, sl + 1);
+		}
+	}
 	return *this;
 }
 
+string & string::operator+=(char c)
+{
+	if (cstr)
+	{
+		char l = cstr[0] + 1;
+		char * p = malloc(l + 2);
+		p[0] = l;
+		smemcpy(p + 1, cstr + 1, cstr[0]);
+		p[l] = c;
+		p[l + 1] = 0;
+		free(cstr);
+		cstr = c;
+	}
+	else
+	{
+		cstr = malloc(3);
+		cstr[0] = 1;
+		cstr[1] = c;
+		cstr[2] = 0;
+	}	
+}
+
+
 inline const char * string::tocstr(void) const
 {
-	return cstr;
+	if (cstr)
+		return cstr + 1;
+	else
+		return "";
 }
 
 inline unsigned string::size(void) const
 {
-	return strlen(cstr);
+	if (cstr)
+		return cstr[0];
+	else
+		return 0;
 }
 
-string string::operator+(const string & s)
+string string::operator+(const string & s) const
 {
-	return string(cstr, s.cstr);
+	if (cstr)
+	{
+		if (s.cstr)
+		{
+			char l = cstr[0] + s.cstr[0];
+			char * p = malloc(l + 2);
+			smemcpy(p + 1, cstr + 1, cstr[0]);
+			smemcpy(p + 1 + cstr[0], s.cstr + 1, s.cstr[0]);
+			return string(l, p);
+		}
+		else
+			return *this;
+	}
+	else
+		return s;
 }
 
-string string::operator+(const char * s)
+string string::operator+(const char * s) const
 {
-	return string(cstr, s);
+	if (cstr)
+	{
+		char sl = strlen(s);
+		if (sl)
+		{
+			char l = cstr[0] + sl;
+			char * p = malloc(l + 2);
+			smemcpy(p + 1, cstr + 1, cstr[0]);
+			smemcpy(p + 1 + cstr[0], s, sl);
+			return string(l, p);
+		}
+		else
+			return *this;
+	}
+	else
+		return string(s);
 }
 
+string string::operator+(char c) const
+{
+	if (cstr)
+	{
+		char l = cstr[0] + 1;
+		char * p = malloc(l + 2);
+		smemcpy(p + 1, cstr + 1, cstr[0]);
+		p[l] = c;
+		return string(l, p);
+	}
+	else
+		return string(c);
+}
+
+string & string::operator<<=(char n)
+{
+	if (n > 0 && cstr)
+	{
+		if (n >= cstr[0])
+		{
+			free(cstr);
+			cstr = nullptr;
+		}
+		else
+		{
+			char i = 1;
+			n++;
+			while (cstr[n])
+				cstr[i++] = cstr[n++];
+			cstr[i] = 0;
+			cstr[0] = i - 1;
+		}
+	}
+	return *this;
+}
+
+string & string::operator>>=(char n)
+{
+	if (n > 0 && cstr)
+	{
+		if (n >= cstr[0])
+		{
+			free(cstr);
+			cstr = nullptr;
+		}
+		else
+		{
+			cstr[0] -= n;
+			cstr[n + 1] = 0;
+		}
+	}
+	return *this;
+}
+
+string string::operator<<(char n) const
+{
+	if (n > 0 && cstr)
+	{
+		if (n >= cstr[0])
+			return string();
+		else
+		{
+
+		}
+	}
+	else
+		return *this;
+}
+
+string string::operator>>(char n) const
+{
+
+}
+
+static int scmp(const char * s1, const char * s2)
+{
+	char n = 0;
+	while (s1[n])
+	{
+		if (s1[n] != s2[n])
+			return s1[n] - s2[n];
+		n++;
+	}
+	return 0;
+}
 
 inline bool string::operator==(const string & s) const
 {
-	return strcmp(cstr, s.cstr) == 0;
+	if (cstr && s.cstr)
+		return scmp(cstr + 1, s.cstr + 1) == 0;
+	else
+		return !cstr && !s.cstr;
 }
 
 inline bool string::operator==(const char * s) const
 {
-	return strcmp(cstr, s) == 0;
+	if (cstr)
+		return scmp(cstr + 1, s) == 0;
+	else
+		return s[0] == 0;
 }
 
 inline bool string::operator!=(const string & s) const
 {
-	return strcmp(cstr, s.cstr) != 0;
+	if (cstr && s.cstr)
+		return scmp(cstr + 1, s.cstr + 1) != 0;
+	else
+		return cstr || s.cstr;
 }
 
 inline bool string::operator!=(const char * s) const
 {
-	return strcmp(cstr, s) == 0;
+	if (cstr)
+		return scmp(cstr + 1, s) == 0;
+	else
+		return s[0] != 0;
 }
 
 inline bool string::operator<(const string & s) const
 {
-	return strcmp(cstr, s.cstr) < 0;
+	if (cstr && s.cstr)
+		return scmp(cstr + 1, s.cstr + 1) < 0;
+	else
+		return s.cstr;
 }
 
 inline bool string::operator<(const char * s) const
 {
-	return strcmp(cstr, s) < 0;
+	if (cstr)
+		return scmp(cstr + 1, s) < 0;
+	else
+		return s[0] != 0;
 }
 
 inline bool string::operator<=(const string & s) const
 {
-	return strcmp(cstr, s.cstr) <= 0;
+	if (cstr && s.cstr)
+		return scmp(cstr + 1, s.cstr + 1) <= 0;
+	else
+		return !cstr || s.cstr;
 }
 
 inline bool string::operator<=(const char * s) const
 {
-	return strcmp(cstr, s) <= 0;
+	if (cstr)
+		return scmp(cstr + 1, s) <= 0;
+	else
+		return true;
 }
 
 inline bool string::operator>(const string & s) const
 {
-	return strcmp(cstr, s.cstr) > 0;
+	if (cstr && s.cstr)
+		return scmp(cstr + 1, s.cstr + 1) > 0;
+	else
+		return cstr;
 }
 
 inline bool string::operator>(const char * s) const
 {
-	return strcmp(cstr, s) > 0;
+	if (cstr)
+		return scmp(cstr + 1, s) > 0;
+	else
+		return false;
 }
 
 inline bool string::operator>=(const string & s) const
 {
-	return strcmp(cstr, s.cstr) >= 0;
+	if (cstr && s.cstr)
+		return scmp(cstr + 1, s.cstr + 1) >= 0;
+	else
+		return cstr || !s.cstr;
 }
 
 inline bool string::operator>=(const char * s) const
 {
-	return strcmp(cstr, s) >= 0;
+	if (cstr)
+		return scmp(cstr + 1, s) >= 0;
+	else
+		return s[0] == 0;
 }
 
-inline char & string::operator[](unsigned t)
+inline char & string::operator[](char t)
 {
-	return cstr[t];
+	return cstr[t + 1];
 }
 
-inline char string::operator[](unsigned t) const
+inline char string::operator[](char t) const
 {
-	return cstr[t];
+	return cstr[t + 1];
+}
+
+string string::substr(char pos, char len) const
+{
+	if (!cstr || len == 0 || pos >= cstr[0])
+		return string;
+	else
+	{
+		char l = cstr[0];
+		if (pos + len > l)
+			len = l - pos;
+
+		char * p = malloc(len + 2);
+		memcpy(p + 1, cstr + 1 + pos, len);
+		return string(len, p);
+	}
+}
+
+inline int string::find(const string & s) const
+{
+	return find(s, 0);
+}
+
+inline int string::find(const char * s) const
+{
+	return find(s, 0);
+}
+
+inline int string::find(char c) const
+{
+	return find(c, 0);
+}
+
+int string::find(const string & s, char pos) const
+{
+	if (!s.cstr)
+		return pos;
+	if (cstr)
+	{
+		char l = cstr[0];
+		char sl = s.cstr[0];
+		if (sl <= l)
+		{
+			l -= sl;
+
+			while (pos <= l)
+			{
+				char i = 1;
+				while (s.cstr[i] && s.cstr[i] == cstr[pos + i])
+					i++;
+				if (!s.cstr[i])
+					return pos;
+				pos++;
+			}
+		}
+	}
+
+	return -1;
+}
+
+int string::find(const char * s, char pos) const
+{
+	if (cstr)
+	{
+		char l = cstr[0];
+		char sl = strlen(s);
+		if (sl <= l)
+		{
+			l -= sl;
+
+			while (pos <= l)
+			{
+				char i = 0;
+				while (s[i] && s[i] == cstr[pos + i + 1])
+					i++;
+				if (!s[i])
+					return pos;
+				pos++;
+			}
+		}
+	}
+
+	return -1;
+}
+
+int string::find(char c, char pos) const
+{
+	if (cstr)
+	{
+		char l = cstr[0];
+		while (pos < l)
+		{
+			if (cstr[pos + 1] == c)
+				return pos;
+			pos++;
+		}		
+	}
+
+	return -1;
 }
diff --git a/include/opp/string.h b/include/opp/string.h
index bde2f0a..ac4f784 100644
--- a/include/opp/string.h
+++ b/include/opp/string.h
@@ -9,20 +9,28 @@ private:
 public:
 	string(void);
 	string(const string & s);
-	string(const char * s);
-	string(const char * s1, const char * s2);
+	__noinline string(const char * s);
+	string(char c);
 	~string(void);
 
 	unsigned size(void) const;
-	
+
 	string & operator=(const string & s);
 	string & operator=(const char * s);
 
 	string & operator+=(const string & s);
 	string & operator+=(const char * s);
+	string & operator+=(char c);
 
-	string operator+(const string & s);
-	string operator+(const char * s);
+	string operator+(const string & s) const;
+	string operator+(const char * s) const;
+	string operator+(char c) const;
+
+	string & operator<<=(char n);
+	string & operator>>=(char n);
+
+	string operator<<(char n) const;
+	string operator>>(char n) const;
 
 	bool operator==(const string & s) const;
 	bool operator==(const char * s) const;
@@ -39,10 +47,22 @@ public:
 	bool operator>=(const string & s) const;
 	bool operator>=(const char * s) const;
 
-	char & operator[](unsigned t);
-	char operator[](unsigned t) const;
+	char & operator[](char t);
+	char operator[](char t) const;
 
 	const char * tocstr(void) const;
+
+	string substr(char pos, char len) const;
+
+	int find(const string & s) const;
+	int find(const char * s) const;
+	int find(char c) const;
+
+	int find(const string & s, char pos) const;
+	int find(const char * s, char pos) const;
+	int find(char c, char pos) const;
+protected:
+	string(char l, char * b);
 };
 
 #pragma compile("string.cpp")
diff --git a/include/stdlib.c b/include/stdlib.c
index a181c0a..7b5709e 100644
--- a/include/stdlib.c
+++ b/include/stdlib.c
@@ -524,6 +524,22 @@ void exit(int status)
 	}
 }
 
+extern struct Heap {
+	Heap	*	next, * end;
+}	HeapNode;
+
+unsigned heapfree(void)
+{
+	unsigned	avail = 0;
+	Heap	*	h = HeapNode.next;
+	while (h)
+	{
+		avail += (h->end - h) * sizeof(Heap);
+		h = h->next;
+	}
+	return avail;
+}
+
 #if 0
 struct Heap {
 	unsigned int	size;
diff --git a/include/stdlib.h b/include/stdlib.h
index 7384454..4d4eac5 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -43,6 +43,8 @@ void free(void * ptr);
 
 void * calloc(int num, int size);
 
+unsigned heapfree(void);
+
 unsigned int rand(void);
 
 void srand(unsigned int seed);
diff --git a/oscar64/InterCode.cpp b/oscar64/InterCode.cpp
index ff056cf..91b1108 100644
--- a/oscar64/InterCode.cpp
+++ b/oscar64/InterCode.cpp
@@ -4428,6 +4428,9 @@ void InterCodeBasicBlock::Append(InterInstruction * code)
 		assert(code->mSrc[1].mType != IT_POINTER);
 	}
 
+	for (int i = 0; i < code->mNumOperands; i++)
+		assert(code->mSrc[i].mType != IT_NONE);
+
 	assert(!(code->mInUse));
 	code->mInUse = true;
 	this->mInstructions.Push(code);
@@ -16126,7 +16129,7 @@ void InterCodeProcedure::Close(void)
 {
 	GrowingTypeArray	tstack(IT_NONE);
 
-	CheckFunc = !strcmp(mIdent->mString, "setspr");
+	CheckFunc = !strcmp(mIdent->mString, "test_find");
 
 	mEntryBlock = mBlocks[0];
 
diff --git a/oscar64/InterCodeGenerator.cpp b/oscar64/InterCodeGenerator.cpp
index bd1a538..8908ed9 100644
--- a/oscar64/InterCodeGenerator.cpp
+++ b/oscar64/InterCodeGenerator.cpp
@@ -1007,8 +1007,9 @@ InterCodeGenerator::ExValue InterCodeGenerator::TranslateInline(Declaration* pro
 
 			InterInstruction* wins = new InterInstruction(texp->mLocation, IC_STORE);
 			wins->mSrc[1].mMemory = IM_INDIRECT;
-			wins->mSrc[0].mType = InterTypeOf(vr.mType);;
+			wins->mSrc[0].mType = vr.mReference > 0 ? IT_POINTER : InterTypeOf(vr.mType);
 			wins->mSrc[0].mTemp = vr.mTemp;
+			assert(wins->mSrc[0].mType != IT_NONE);
 			wins->mSrc[1].mType = IT_POINTER;
 			wins->mSrc[1].mTemp = ains->mDst.mTemp;
 			if (pdec)
@@ -3195,6 +3196,7 @@ InterCodeGenerator::ExValue InterCodeGenerator::TranslateExpression(Declaration*
 					block->Append(defins[i]);
 
 				InterInstruction	*	cins = new InterInstruction(exp->mLocation, IC_CALL);
+				cins->mNumOperands = 1;
 				if (funcexp->mDecValue && (funcexp->mDecValue->mFlags & DTF_NATIVE))
 					cins->mCode = IC_CALL_NATIVE;
 				else
diff --git a/oscar64/NativeCodeGenerator.cpp b/oscar64/NativeCodeGenerator.cpp
index b0a1fe5..95f6dcc 100644
--- a/oscar64/NativeCodeGenerator.cpp
+++ b/oscar64/NativeCodeGenerator.cpp
@@ -28951,7 +28951,7 @@ bool NativeCodeBasicBlock::OptimizeSimpleLoopInvariant(NativeCodeProcedure* proc
 				i++;
 				while (i < mIns.Size() && !mIns[i].ReferencesZeroPage(mIns[si].mAddress))
 					i++;
-				if (i < mIns.Size() && (mIns[i].mType == ASMIT_DEC || mIns[i].mType == ASMIT_INC))
+				if (i < mIns.Size() && (mIns[i].mType == ASMIT_DEC || mIns[i].mType == ASMIT_INC) && (!(mIns[ei].mLive & LIVE_CPU_REG_Z) || mIns[ei].ChangesAccuAndFlag()))
 				{
 					int j = i + 1;
 					while (j < mIns.Size() && !mIns[j].ReferencesZeroPage(mIns[si].mAddress))
@@ -28961,6 +28961,9 @@ bool NativeCodeBasicBlock::OptimizeSimpleLoopInvariant(NativeCodeProcedure* proc
 						// So we have an LDX from ZP, and exactly one INC/DECof this ZP and X never changes in the loop
 						if (!prevBlock)
 							return OptimizeSimpleLoopInvariant(proc, full);
+
+						bool needRecheck = mIns[ei].mLive & LIVE_CPU_REG_Z;
+
 						prevBlock->mIns.Push(mIns[si]);
 						exitBlock->mIns.Insert(0, NativeCodeInstruction(mIns[si].mIns, ASMIT_STX, mIns[si]));
 						mIns[si].mType = ASMIT_NOP;
@@ -28975,6 +28978,12 @@ bool NativeCodeBasicBlock::OptimizeSimpleLoopInvariant(NativeCodeProcedure* proc
 						mIns[i].mType = ASMIT_NOP;
 						mIns[i].mMode = ASMIM_IMPLIED;
 
+						if (needRecheck)
+						{
+							mIns[ei].mLive |= LIVE_CPU_REG_A;
+							mIns.Insert(ei + 1, NativeCodeInstruction(mIns[ei].mIns, ASMIT_ORA, ASMIM_IMMEDIATE, 0));
+						}
+
 						mIns.Insert(ei + 1, NativeCodeInstruction(mIns[i].mIns, t));
 
 						for (int i = 0; i < mIns.Size(); i++)
@@ -31171,6 +31180,7 @@ bool NativeCodeBasicBlock::OptimizeGenericLoop(NativeCodeProcedure* proc)
 					NativeCodeBasicBlock* block = lblocks[i];
 
 					int	yoffset = 0, xoffset = 0, aoffset = 0;
+					int yskew = 0, xskew = 0;
 
 					for (int j = 0; j < block->mIns.Size(); j++)
 					{
@@ -31189,6 +31199,7 @@ bool NativeCodeBasicBlock::OptimizeGenericLoop(NativeCodeProcedure* proc)
 								zareg[ins.mAddress] = -1;
 							}
 							yoffset = 0;
+							yskew = 0;
 							zareg[CPU_REG_Y] = -1;
 							break;
 						case ASMIT_LDX:
@@ -31202,6 +31213,7 @@ bool NativeCodeBasicBlock::OptimizeGenericLoop(NativeCodeProcedure* proc)
 								zareg[ins.mAddress] = -1;
 							}
 							xoffset = 0;
+							xskew = 0;
 							zareg[CPU_REG_X] = -1;
 							break;
 						case ASMIT_STY:
@@ -31235,13 +31247,35 @@ bool NativeCodeBasicBlock::OptimizeGenericLoop(NativeCodeProcedure* proc)
 							zareg[CPU_REG_X] = -1;
 							break;
 						case ASMIT_INC:
+							if (ins.mMode == ASMIM_ZERO_PAGE)
+							{
+								if (zxreg[ins.mAddress] >= 0)
+								{
+									zxreg[ins.mAddress] += 3;
+									xskew++;
+								}
+								if (zyreg[ins.mAddress] >= 0)
+								{
+									zyreg[ins.mAddress] += 3;
+									yskew++;
+								}
+
+								zareg[ins.mAddress] = -1;
+							}
+							break;
 						case ASMIT_DEC:
 							if (ins.mMode == ASMIM_ZERO_PAGE)
 							{
 								if (zxreg[ins.mAddress] >= 0)
+								{
 									zxreg[ins.mAddress] += 3;
+									xskew--;
+								}
 								if (zyreg[ins.mAddress] >= 0)
+								{
 									zyreg[ins.mAddress] += 3;
+									yskew--;
+								}
 
 								zareg[ins.mAddress] = -1;
 							}
@@ -31335,6 +31369,11 @@ bool NativeCodeBasicBlock::OptimizeGenericLoop(NativeCodeProcedure* proc)
 								areg = -2;
 						}
 
+						if (xreg >= 0 && ins.mMode == ASMIM_ABSOLUTE_X && xskew != xoffset)
+							zxreg[xreg] = -1;
+						if (yreg >= 0 && (ins.mMode == ASMIM_ABSOLUTE_Y || ins.mMode == ASMIM_INDIRECT_Y) && yskew != yoffset)
+							zyreg[yreg] = -1;
+
 						if (!(ins.mLive & LIVE_CPU_REG_Y))
 							yoffset = 0;
 						if (!(ins.mLive & LIVE_CPU_REG_X))
@@ -40154,7 +40193,7 @@ void NativeCodeProcedure::Compile(InterCodeProcedure* proc)
 {
 	mInterProc = proc;
 
-	CheckFunc = !strcmp(mInterProc->mIdent->mString, "heapcheck");
+	CheckFunc = !strcmp(mInterProc->mIdent->mString, "test_find");
 
 	int	nblocks = proc->mBlocks.Size();
 	tblocks = new NativeCodeBasicBlock * [nblocks];