From 37416a61cb3e4beb571d21159f757c0e2532a2d2 Mon Sep 17 00:00:00 2001
From: drmortalwombat <90205530+drmortalwombat@users.noreply.github.com>
Date: Sun, 18 Jun 2023 10:20:50 +0200
Subject: [PATCH] Add struct inheritance in cpp mode

---
 oscar64/Declaration.cpp        | 22 ++++++++++++++++++----
 oscar64/Errors.h               |  1 +
 oscar64/InterCodeGenerator.cpp | 23 ++++++++++++++---------
 oscar64/Parser.cpp             | 18 +++++++++++++++++-
 4 files changed, 50 insertions(+), 14 deletions(-)

diff --git a/oscar64/Declaration.cpp b/oscar64/Declaration.cpp
index f153ec0..ba35f6f 100644
--- a/oscar64/Declaration.cpp
+++ b/oscar64/Declaration.cpp
@@ -794,7 +794,7 @@ bool Declaration::IsSubType(const Declaration* dec) const
 
 	if (mType != dec->mType)
 		return false;
-	if (mSize != dec->mSize)
+	if (mType != DT_TYPE_STRUCT && mSize != dec->mSize)
 		return false;
 	if (mStripe != dec->mStripe)
 		return false;
@@ -810,7 +810,15 @@ bool Declaration::IsSubType(const Declaration* dec) const
 	else if (mType == DT_TYPE_BOOL || mType == DT_TYPE_FLOAT || mType == DT_TYPE_VOID)
 		return true;
 	else if (mType == DT_TYPE_STRUCT || mType == DT_TYPE_ENUM)
-		return mScope == dec->mScope || (mIdent == dec->mIdent && mSize == dec->mSize);
+	{
+		if (mScope == dec->mScope || (mIdent == dec->mIdent && mSize == dec->mSize))
+			return true;
+
+		if (dec->mBase)
+			return IsSubType(dec->mBase);
+
+		return false;
+	}
 	else if (mType == DT_TYPE_UNION)
 		return false;
 	else if (mType == DT_TYPE_ARRAY)
@@ -964,7 +972,7 @@ bool Declaration::IsSameValue(const Declaration* dec) const
 bool Declaration::CanAssign(const Declaration* fromType) const
 {
 	if (mType == DT_TYPE_REFERENCE)
-		return fromType->IsSubType(mBase);
+		return mBase->IsSubType(fromType);
 	else if (fromType->mType == DT_TYPE_REFERENCE)
 		return this->CanAssign(fromType->mBase);
 
@@ -976,7 +984,13 @@ bool Declaration::CanAssign(const Declaration* fromType) const
 			return true;
 	}
 	else if (mType == DT_TYPE_STRUCT && fromType->mType == DT_TYPE_STRUCT)
-		return mScope == fromType->mScope || (mIdent == fromType->mIdent && mSize == fromType->mSize);
+	{
+		if (mScope == fromType->mScope || (mIdent == fromType->mIdent && mSize == fromType->mSize))
+			return true;
+		if (fromType->mBase)
+			return this->CanAssign(fromType->mBase);
+		return false;
+	}
 	else if (mType == DT_TYPE_POINTER)
 	{
 		if (fromType->mType == DT_TYPE_POINTER || fromType->mType == DT_TYPE_ARRAY)
diff --git a/oscar64/Errors.h b/oscar64/Errors.h
index 24d9f73..23724de 100644
--- a/oscar64/Errors.h
+++ b/oscar64/Errors.h
@@ -71,6 +71,7 @@ enum ErrorID
 	ERRR_STRIPE_REQUIRES_FIXED_SIZE_ARRAY,
 	ERRR_CANNOT_FIND_BANK_OF_EXPRESSION,
 	ERRO_NOT_A_NAMESPACE,
+	ERRO_NOT_A_BASE_CLASS,
 
 	ERRR_STACK_OVERFLOW,
 	ERRR_INVALID_NUMBER,
diff --git a/oscar64/InterCodeGenerator.cpp b/oscar64/InterCodeGenerator.cpp
index a49882c..70418cd 100644
--- a/oscar64/InterCodeGenerator.cpp
+++ b/oscar64/InterCodeGenerator.cpp
@@ -77,6 +77,11 @@ InterCodeGenerator::ExValue InterCodeGenerator::CoerceType(InterCodeProcedure* p
 
 		return v;
 	}
+	else if (type->mType == DT_TYPE_STRUCT && type->mBase->IsSubType(v.mType))
+	{
+		v.mType = type;
+		return v;
+	}
 
 	if (v.mType->IsIntegerType() && type->mType == DT_TYPE_FLOAT)
 	{
@@ -936,15 +941,15 @@ InterCodeGenerator::ExValue InterCodeGenerator::TranslateInline(Declaration* pro
 				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].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 = vr.mType->mSize;
+				cins->mSrc[1].mOperandSize = vp.mType->mSize;
 
-				cins->mConst.mOperandSize = vr.mType->mSize;
+				cins->mConst.mOperandSize = vp.mType->mSize;
 				block->Append(cins);
 			}
 		}
@@ -2636,15 +2641,15 @@ InterCodeGenerator::ExValue InterCodeGenerator::TranslateExpression(Declaration*
 							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].mOperandSize = vp.mType->mSize;
 							cins->mSrc[0].mStride = vr.mType->mStripe;
 
-							cins->mSrc[1].mOperandSize = vr.mType->mSize;
+							cins->mSrc[1].mOperandSize = vp.mType->mSize;
 							cins->mSrc[1].mType = IT_POINTER;
 							cins->mSrc[1].mTemp = ains->mDst.mTemp;
 							cins->mSrc[1].mMemory = IM_INDIRECT;
 
-							cins->mConst.mOperandSize = vr.mType->mSize;
+							cins->mConst.mOperandSize = vp.mType->mSize;
 							block->Append(cins);
 						}
 
@@ -2969,15 +2974,15 @@ InterCodeGenerator::ExValue InterCodeGenerator::TranslateExpression(Declaration*
 					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].mOperandSize = procType->mBase->mSize;
 					cins->mSrc[0].mStride = vr.mType->mStripe;
 
-					cins->mSrc[1].mOperandSize = vr.mType->mSize;
+					cins->mSrc[1].mOperandSize = procType->mBase->mSize;
 					cins->mSrc[1].mType = IT_POINTER;
 					cins->mSrc[1].mTemp = ains->mDst.mTemp;
 					cins->mSrc[1].mMemory = IM_INDIRECT;
 
-					cins->mConst.mOperandSize = vr.mType->mSize;
+					cins->mConst.mOperandSize = procType->mBase->mSize;
 					block->Append(cins);
 				}
 				else
diff --git a/oscar64/Parser.cpp b/oscar64/Parser.cpp
index 5258353..0be34af 100644
--- a/oscar64/Parser.cpp
+++ b/oscar64/Parser.cpp
@@ -39,7 +39,7 @@ Declaration* Parser::ParseStructDeclaration(uint64 flags, DecType dt)
 		structName = mScanner->mTokenIdent;
 		mScanner->NextToken();
 		Declaration* edec = mScope->Lookup(structName);
-		if (edec && mScanner->mToken != TK_OPEN_BRACE)
+		if (edec && mScanner->mToken != TK_OPEN_BRACE && mScanner->mToken != TK_COLON)
 		{
 			dec = edec;
 		}
@@ -67,6 +67,22 @@ Declaration* Parser::ParseStructDeclaration(uint64 flags, DecType dt)
 		dec->mScope = new DeclarationScope(nullptr, SLEVEL_CLASS);
 	}
 
+	if ((mCompilerOptions & COPT_CPLUSPLUS) && mScanner->mToken == TK_COLON)
+	{
+		mScanner->NextToken();
+		Declaration* pdec = ParseQualIdent();
+		if (pdec)
+		{
+			if (pdec->mType == DT_TYPE_STRUCT)
+			{
+				dec->mBase = pdec;
+				dec->mSize = pdec->mSize;
+			}
+			else
+				mErrors->Error(mScanner->mLocation, ERRO_NOT_A_BASE_CLASS, "Not a base class", dec->mIdent);
+		}
+	}
+
 	if (mScanner->mToken == TK_OPEN_BRACE)
 	{
 		mScanner->NextToken();