From 7858e32d126b986bdf46648f23e35d9e5efaf462 Mon Sep 17 00:00:00 2001
From: drmortalwombat <90205530+drmortalwombat@users.noreply.github.com>
Date: Sun, 15 Oct 2023 20:17:04 +0200
Subject: [PATCH] Improve handling of single member structs

---
 include/opp/slab.h             |  80 ++++++++++
 include/opp/static_vector.h    | 258 +++++++++++++++++++++++++++++++++
 oscar64/InterCode.cpp          |  29 ++++
 oscar64/InterCodeGenerator.cpp | 124 +++++++++-------
 oscar64/InterCodeGenerator.h   |   1 +
 oscar64/Parser.cpp             |   2 +-
 6 files changed, 439 insertions(+), 55 deletions(-)
 create mode 100644 include/opp/slab.h
 create mode 100644 include/opp/static_vector.h

diff --git a/include/opp/slab.h b/include/opp/slab.h
new file mode 100644
index 0000000..1a61d4d
--- /dev/null
+++ b/include/opp/slab.h
@@ -0,0 +1,80 @@
+#ifndef OPP_SLAB_H
+#define OPP_SLAB_H
+
+template<class T, int N>
+class slabptr
+{
+public:
+	char	index;
+
+	slabptr(void)
+		: index(N)
+		{}
+
+	slabptr(char i)
+		: index(i)
+		{}
+
+	slabptr(const slabptr & i)
+		: index(i.index)
+		{}
+
+	auto operator-> ();
+	auto & operator* ();
+};
+
+template <class T, int N>
+class slab
+{
+protected:
+	static __striped	T	buffer[N];
+	static	char		head;
+	static	char		next[N];
+
+public:
+	typedef slabptr<T, N>	ptr;
+
+	static void init(void);
+	static auto alloc(void);
+	static void free(ptr p);
+};
+
+
+template<class T, int N>
+inline auto slabptr<T, N>::operator-> ()
+{
+	return slab<T, N>::buffer + index;
+}
+
+template<class T, int N>
+inline auto & slabptr<T, N>::operator* ()
+{
+	return slab<T, N>::buffer[index];	
+}
+
+
+template <class T, int N>
+void slab<T, N>::init(void)
+{
+	head = 0;
+	for(char i=0; i<N; i++)
+		next[i] = i + 1;
+}
+
+template <class T, int N>
+auto slab<T, N>::alloc(void)
+{
+	char i = head;
+	head = next[head];	
+	return slabptr<T, N>(i);	
+}
+
+template <class T, int N>
+void slab<T, N>::free(slabptr<T, N> p)
+{
+	next[p.index] = head;
+	head = p.index;
+}
+
+#endif
+
diff --git a/include/opp/static_vector.h b/include/opp/static_vector.h
new file mode 100644
index 0000000..c5358c6
--- /dev/null
+++ b/include/opp/static_vector.h
@@ -0,0 +1,258 @@
+#ifndef OPP_STATIC_VECTOR_H
+#define OPP_STATIC_VECTOR_H
+
+#include <new>
+#include <stdlib.h>
+#include <opp/utility.h>
+
+namespace opp {
+
+template <class T, int N>
+class static_vector
+{
+protected:
+	char	_space[N * sizeof(T)];
+	enum { m = N }	_size;
+public:
+	typedef T 	element_type;
+
+	static_vector(void) : _size(0) {}
+
+	static_vector(size_t n) : _size(n) 
+	{
+		T *	data = (T*)_space;
+		for(size_t i=0; i<n; i++)
+			new (data + i) T;
+	}
+
+	static_vector(const static_vector & v)
+		: _size(v._size) 
+	{
+		T *	data = (T*)_space, * vdata = (T*)(v._space);
+		for(size_t i=0; i<_size; i++)
+			new (data + i)T(vdata[i]);
+	}
+
+	~static_vector(void)
+	{
+		T *	data = (T*)_space;
+		for(size_t i=0; i<_size; i++)
+			data[i].~T();
+	}
+
+	static_vector & operator=(const static_vector & v)
+	{
+		if (this != &v)
+		{
+			T *	data = (T*)_space, * vdata = (T*)(v._space);
+			for(size_t i=0; i<_size; i++)
+				data[i].~T();
+			_size = v._size; 
+			for(size_t i=0; i<_size; i++)
+				new (data + i)T(vdata[i]);
+		}
+		return *this;
+	}
+
+	size_t size(void) const
+	{
+		return _size;
+	}
+
+	size_t max_size(void) const
+	{
+		return N;
+	}
+
+	bool empty(void) const
+	{
+		return _size == 0;
+	}
+
+	size_t capacity(void) const
+	{
+		return N;
+	}
+
+	void resize(size_t n);
+
+	T & at(size_t at)
+	{
+		return ((T*)_space)[at];
+	}
+
+	const T & at(size_t at) const
+	{
+		return ((T*)_space)[at];
+	}
+
+	T & operator[](size_t at)
+	{
+		return ((T*)_space)[at];
+	}
+
+	const T & operator[](size_t at) const
+	{
+		return ((T*)_space)[at];
+	}
+
+	T * begin(void)
+	{
+		return (T*)_space;
+	}
+
+	const T * begin(void) const
+	{
+		return (T*)_space;
+	}
+
+	const T * cbegin(void) const
+	{
+		return (T*)_space;
+	}
+
+	T * end(void)
+	{
+		return (T*)_space + _size;
+	}
+
+	const T * end(void) const
+	{
+		return (T*)_space + _size;
+	}
+
+	const T * cend(void) const
+	{
+		return (T*)_space + _size;
+	}
+
+	T & front(void)
+	{
+		return ((T*)_space)[0];
+	}
+
+	const T & front(void) const
+	{
+		return ((T*)_space)[0];
+	}
+
+	T & back(void)
+	{
+		return ((T*)_space)[_size - 1];
+	}
+
+	const T & back(void) const
+	{
+		return ((T*)_space)[_size - 1];
+	}
+
+	T * data(void)
+	{
+		return (T*)_space;
+	}
+
+	const T * at(void) const
+	{
+		return (T*)_space;
+	}
+
+	void push_back(const T & t);
+
+	void push_back(T && t);
+
+	void pop_back(void)
+	{
+		_size--;
+		((T*)_space)[_size].~T();
+	}
+
+	void insert(size_t at, const T & t);
+
+	void erase(size_t at, size_t n = 1);
+
+	T * insert(T * at, const T & t);
+
+	template <typename ...P>
+	void emplace_back(const P&... p);
+};
+
+
+
+template <class T, int N>
+void static_vector<T, N>::resize(size_t n)
+{
+	T *	data = (T*)_space;
+	if (n < _size)
+	{
+		for(size_t i=n; i<_size; i++)
+			data[i].~T();			
+		_size = n;
+	}
+	else
+	{
+		for(size_t i=_size; i<n; i++)
+			new(data + i)T;
+		_size = n;
+	}
+}
+
+template <class T, int N>
+void static_vector<T, N>::push_back(const T & t)
+{
+	new ((T*)_space + _size++)T(t);
+}
+
+template <class T, int N>
+void static_vector<T, N>::push_back(T && t)
+{
+	new ((T*)_space + _size++)T(t);
+}
+
+template <class T, int N>
+template <typename ...P>
+void static_vector<T, N>::emplace_back(const P&... p)
+{
+	new ((T*)_space + _size++)T(p...);
+}
+
+template <class T, int N>
+void static_vector<T, N>::insert(size_t at, const T & t)
+{
+	T *	data = (T*)_space;
+	new (data + _size)T;
+	for(size_t i=_size; i>at; i--)
+		data[i] = move(data[i - 1]);
+	data[at] = t;
+	_size++;
+}
+
+template <class T, int N>
+void static_vector<T, N>::erase(size_t at, size_t n)
+{
+	T *	data = (T*)_space;
+	_size -= n;
+	for(size_t i=at; i<_size; i++)
+		data[i] = move(data[i + n]);
+	for(size_t i=0; i<n; i++)
+		data[_size + i].~T();
+}
+
+template <class T, int N>
+T * static_vector<T, N>::insert(T * at, const T & t)
+{
+	T *	data = (T*)_space;
+	T * dp = data + _size;
+	new (dp)T;
+	while (dp != at)
+	{
+		dp--;
+		dp[1] = move(dp[0]);
+	}
+	dp[0] = t;
+	_size++;
+	return dp + 1;
+}
+
+}
+#endif
+
diff --git a/oscar64/InterCode.cpp b/oscar64/InterCode.cpp
index ef3c474..086b690 100644
--- a/oscar64/InterCode.cpp
+++ b/oscar64/InterCode.cpp
@@ -16173,6 +16173,35 @@ bool InterCodeBasicBlock::PeepholeReplaceOptimization(const GrowingVariableArray
 				changed = true;
 			}
 		}
+#endif
+#if 1
+		if (i + 1 < mInstructions.Size())
+		{
+			if (mInstructions[i + 0]->mCode == IC_LEA && mInstructions[i + 0]->mSrc[1].mTemp < 0 &&
+				mInstructions[i + 1]->mCode == IC_RELATIONAL_OPERATOR && mInstructions[i + 1]->mSrc[1].mTemp == mInstructions[i + 0]->mDst.mTemp && mInstructions[i + 1]->mSrc[0].mTemp < 0 &&
+				mInstructions[i + 1]->mSrc[0].mMemory == IM_ABSOLUTE && mInstructions[i + 1]->mSrc[0].mIntConst == 0)
+			{
+				if (mInstructions[i + 0]->mSrc[1].mMemory != IM_ABSOLUTE)
+				{
+					if (mInstructions[i + 1]->mOperator == IA_CMPEQ)
+					{
+						mInstructions[i + 1]->mNumOperands = 0;
+						mInstructions[i + 1]->mCode = IC_CONSTANT;
+						mInstructions[i + 1]->mConst.mType = IT_BOOL;
+						mInstructions[i + 1]->mConst.mIntConst = 0;
+						changed = true;
+					}
+					else if (mInstructions[i + 1]->mOperator == IA_CMPNE)
+					{
+						mInstructions[i + 1]->mNumOperands = 0;
+						mInstructions[i + 1]->mCode = IC_CONSTANT;
+						mInstructions[i + 1]->mConst.mType = IT_BOOL;
+						mInstructions[i + 1]->mConst.mIntConst = 1;
+						changed = true;
+					}
+				}
+			}
+		}
 #endif
 	}
 
diff --git a/oscar64/InterCodeGenerator.cpp b/oscar64/InterCodeGenerator.cpp
index 28cd27c..e520776 100644
--- a/oscar64/InterCodeGenerator.cpp
+++ b/oscar64/InterCodeGenerator.cpp
@@ -1252,24 +1252,7 @@ InterCodeGenerator::ExValue InterCodeGenerator::TranslateInline(Declaration* pro
 				mErrors->Error(exp->mLeft->mLocation, EERR_NOT_AN_LVALUE, "Not an addressable expression");
 
 			if (vp.mTemp != vr.mTemp)
-			{
-				InterInstruction* cins = new InterInstruction(exp->mLocation, IC_COPY);
-				cins->mNumOperands = 2;
-
-				cins->mSrc[0].mType = IT_POINTER;
-				cins->mSrc[0].mTemp = vr.mTemp;
-				cins->mSrc[0].mMemory = IM_INDIRECT;
-				cins->mSrc[0].mOperandSize = vp.mType->mSize;
-				cins->mSrc[0].mStride = vr.mType->mStripe;
-
-				cins->mSrc[1].mType = IT_POINTER;
-				cins->mSrc[1].mTemp = ains->mDst.mTemp;
-				cins->mSrc[1].mMemory = IM_INDIRECT;
-				cins->mSrc[1].mOperandSize = vp.mType->mSize;
-
-				cins->mConst.mOperandSize = vp.mType->mSize;
-				block->Append(cins);
-			}
+				CopyStructSimple(proc, exp, block, vp, vr);
 		}
 		else
 		{
@@ -1390,6 +1373,73 @@ InterCodeGenerator::ExValue InterCodeGenerator::TranslateInline(Declaration* pro
 		return ExValue(TheVoidTypeDeclaration);
 }
 
+void InterCodeGenerator::CopyStructSimple(InterCodeProcedure* proc, Expression * exp, InterCodeBasicBlock* block, ExValue vl, ExValue vr)
+{
+	int		ne = 0;
+	Declaration* mdec = nullptr;
+	if (vl.mType->mType == DT_TYPE_STRUCT)
+	{
+		Declaration* dec = vl.mType->mParams;
+		while (dec)
+		{
+			if (dec->mType == DT_ELEMENT && !(dec->mFlags & DTF_STATIC))
+			{
+				mdec = dec->mBase;
+				ne++;
+			}
+			dec = dec->mNext;
+		}
+	}
+
+	// Single element structs are copied as individual value
+	if (ne == 1 && mdec->mSize == vl.mType->mSize)
+	{
+		InterInstruction* lins = new InterInstruction(exp->mLocation, IC_LOAD);
+		lins->mNumOperands = 1;
+
+		lins->mSrc[0].mType = IT_POINTER;
+		lins->mSrc[0].mTemp = vr.mTemp;
+		lins->mSrc[0].mMemory = IM_INDIRECT;
+		lins->mSrc[0].mOperandSize = mdec->mSize;
+		lins->mSrc[0].mStride = mdec->mStripe;
+
+		lins->mDst.mType = InterTypeOf(mdec);
+		lins->mDst.mTemp = proc->AddTemporary(lins->mDst.mType);
+		block->Append(lins);
+
+		InterInstruction* sins = new InterInstruction(exp->mLocation, IC_STORE);
+		sins->mNumOperands = 2;
+
+		sins->mSrc[1].mType = IT_POINTER;
+		sins->mSrc[1].mTemp = vl.mTemp;
+		sins->mSrc[1].mMemory = IM_INDIRECT;
+		sins->mSrc[1].mOperandSize = mdec->mSize;
+		sins->mSrc[1].mStride = mdec->mStripe;
+
+		sins->mSrc[0] = lins->mDst;
+		block->Append(sins);
+	}
+	else
+	{
+		InterInstruction* cins = new InterInstruction(exp->mLocation, IC_COPY);
+		cins->mNumOperands = 2;
+
+		cins->mSrc[0].mType = IT_POINTER;
+		cins->mSrc[0].mTemp = vr.mTemp;
+		cins->mSrc[0].mMemory = IM_INDIRECT;
+		cins->mSrc[0].mOperandSize = vr.mType->mSize;
+		cins->mSrc[0].mStride = vr.mType->mStripe;
+
+		cins->mSrc[1].mOperandSize = vl.mType->mSize;
+		cins->mSrc[1].mType = IT_POINTER;
+		cins->mSrc[1].mTemp = vl.mTemp;
+		cins->mSrc[1].mMemory = IM_INDIRECT;
+
+		cins->mConst.mOperandSize = vl.mType->mSize;
+		block->Append(cins);
+	}
+}
+
 void InterCodeGenerator::CopyStruct(InterCodeProcedure* proc, Expression* exp, InterCodeBasicBlock*& block, ExValue vl, ExValue vr, InlineMapper* inlineMapper, bool moving)
 {
 	if (vr.mTemp == vl.mTemp)
@@ -1587,24 +1637,7 @@ void InterCodeGenerator::CopyStruct(InterCodeProcedure* proc, Expression* exp, I
 		}
 	}
 	else
-	{
-		InterInstruction* cins = new InterInstruction(exp->mLocation, IC_COPY);
-		cins->mNumOperands = 2;
-
-		cins->mSrc[0].mType = IT_POINTER;
-		cins->mSrc[0].mTemp = vr.mTemp;
-		cins->mSrc[0].mMemory = IM_INDIRECT;
-		cins->mSrc[0].mOperandSize = vr.mType->mSize;
-		cins->mSrc[0].mStride = vr.mType->mStripe;
-
-		cins->mSrc[1].mOperandSize = vl.mType->mSize;
-		cins->mSrc[1].mType = IT_POINTER;
-		cins->mSrc[1].mTemp = vl.mTemp;
-		cins->mSrc[1].mMemory = IM_INDIRECT;
-
-		cins->mConst.mOperandSize = vl.mType->mSize;
-		block->Append(cins);
-	}
+		CopyStructSimple(proc, exp, block, vl, vr);
 }
 
 InterCodeGenerator::ExValue InterCodeGenerator::TranslateExpression(Declaration* procType, InterCodeProcedure* proc, InterCodeBasicBlock*& block, Expression* exp, DestructStack*& destack, const BranchTarget& breakBlock, const BranchTarget& continueBlock, InlineMapper* inlineMapper, ExValue* lrexp)
@@ -2104,24 +2137,7 @@ InterCodeGenerator::ExValue InterCodeGenerator::TranslateExpression(Declaration*
 					mErrors->Error(exp->mLeft->mLocation, EERR_NOT_AN_LVALUE, "Not an addressable expression");
 
 				if (vr.mTemp != vl.mTemp)
-				{
-					InterInstruction* ins = new InterInstruction(exp->mLocation, IC_COPY);
-					ins->mNumOperands = 2;
-
-					ins->mSrc[0].mType = IT_POINTER;
-					ins->mSrc[0].mTemp = vr.mTemp;
-					ins->mSrc[0].mMemory = IM_INDIRECT;
-					ins->mSrc[0].mOperandSize = vl.mType->mSize;
-					ins->mSrc[0].mStride = vr.mType->mStripe;
-
-					ins->mSrc[1].mType = IT_POINTER;
-					ins->mSrc[1].mTemp = vl.mTemp;
-					ins->mSrc[1].mMemory = IM_INDIRECT;
-					ins->mSrc[1].mOperandSize = vl.mType->mSize;
-					ins->mSrc[1].mStride = vl.mType->mStripe;
-					ins->mConst.mOperandSize = vl.mType->mSize;
-					block->Append(ins);
-				}
+					CopyStructSimple(proc, exp, block, vl, vr);
 			}
 			else
 			{
diff --git a/oscar64/InterCodeGenerator.h b/oscar64/InterCodeGenerator.h
index 79f9bb0..67d3e2a 100644
--- a/oscar64/InterCodeGenerator.h
+++ b/oscar64/InterCodeGenerator.h
@@ -87,6 +87,7 @@ protected:
 	void TranslateLogic(Declaration* procType, InterCodeProcedure* proc, InterCodeBasicBlock* block, InterCodeBasicBlock* tblock, InterCodeBasicBlock* fblock, Expression* exp, DestructStack*& destack, InlineMapper* inlineMapper);
 	ExValue TranslateInline(Declaration* procType, InterCodeProcedure* proc, InterCodeBasicBlock*& block, Expression* exp, const BranchTarget& breakBlock, const BranchTarget& continueBlock, InlineMapper* inlineMapper, bool inlineConstexpr, ExValue* lrexp);
 	void CopyStruct(InterCodeProcedure* proc, Expression* exp, InterCodeBasicBlock*& block, ExValue vl, ExValue vr, InlineMapper* inlineMapper, bool moving);
+	void CopyStructSimple(InterCodeProcedure* proc, Expression* exp, InterCodeBasicBlock * block, ExValue vl, ExValue vr);
 	void StoreValue(InterCodeProcedure* proc, Expression* exp, InterCodeBasicBlock*& block, ExValue vl, ExValue vr);
 
 	void UnwindDestructStack(Declaration* procType, InterCodeProcedure* proc, InterCodeBasicBlock*& block, DestructStack* stack, DestructStack * bottom, InlineMapper* inlineMapper);
diff --git a/oscar64/Parser.cpp b/oscar64/Parser.cpp
index 7b7e2d8..b191c87 100644
--- a/oscar64/Parser.cpp
+++ b/oscar64/Parser.cpp
@@ -5334,7 +5334,7 @@ Expression* Parser::ParseSimpleExpression(bool lhs)
 
 			if (dec)
 			{
-				if (dec->mType == DT_ELEMENT || dec->mType == DT_CONST_FUNCTION)
+				if ((dec->mType == DT_ELEMENT || dec->mType == DT_CONST_FUNCTION) && !(dec->mFlags & DTF_STATIC))
 				{
 					Expression* texp = new Expression(mScanner->mLocation, EX_VARIABLE);
 					texp->mDecType = mThisPointer->mBase;