From 3357af32e59ef8be735685a941c5c5a44cb5fd7e Mon Sep 17 00:00:00 2001
From: Randy Heit <rheit@users.noreply.github.com>
Date: Sun, 3 Apr 2016 16:07:51 -0500
Subject: [PATCH] Generalize FxArrayElement to work with all numeric elements
 (not just 32-bit ints)

---
 src/thingdef/thingdef_expression.cpp | 32 ++++++++++++++++++++--------
 src/thingdef/thingdef_parse.cpp      |  1 -
 2 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/src/thingdef/thingdef_expression.cpp b/src/thingdef/thingdef_expression.cpp
index 7ecc3c3c47..0312126d45 100644
--- a/src/thingdef/thingdef_expression.cpp
+++ b/src/thingdef/thingdef_expression.cpp
@@ -2994,10 +2994,10 @@ FxExpression *FxArrayElement::Resolve(FCompileContext &ctx)
 	}
 
 	ValueType = arraytype->ElementType;
-	if (ValueType->GetRegType() != REGT_INT)
+	if (ValueType->GetRegType() != REGT_INT && ValueType->GetRegType() != REGT_FLOAT)
 	{
 		// int arrays only for now
-		ScriptPosition.Message(MSG_ERROR, "Only integer arrays are supported.");
+		ScriptPosition.Message(MSG_ERROR, "Only numeric arrays are supported.");
 		delete this;
 		return NULL;
 	}
@@ -3014,7 +3014,10 @@ FxExpression *FxArrayElement::Resolve(FCompileContext &ctx)
 ExpEmit FxArrayElement::Emit(VMFunctionBuilder *build)
 {
 	ExpEmit start = Array->Emit(build);
-	ExpEmit dest(build, REGT_INT);
+	PArray *const arraytype = static_cast<PArray*>(Array->ValueType);
+	PType *const elementtype = arraytype->ElementType;
+	ExpEmit dest(build, elementtype->GetRegType());
+
 	if (start.Konst)
 	{
 		ExpEmit tmpstart(build, REGT_POINTER);
@@ -3024,19 +3027,30 @@ ExpEmit FxArrayElement::Emit(VMFunctionBuilder *build)
 	if (index->isConstant())
 	{
 		unsigned indexval = static_cast<FxConstant *>(index)->GetValue().GetInt();
-		if (indexval >= static_cast<PArray*>(Array->ValueType)->ElementCount)
+		if (indexval >= arraytype->ElementCount)
 		{
 			I_Error("Array index out of bounds");
 		}
-		indexval <<= 2;
-		build->Emit(OP_LW, dest.RegNum, start.RegNum, build->GetConstantInt(indexval));
+		indexval *= arraytype->ElementSize;
+		build->Emit(arraytype->ElementType->GetLoadOp(), dest.RegNum,
+			start.RegNum, build->GetConstantInt(indexval));
 	}
 	else
 	{
 		ExpEmit indexv(index->Emit(build));
-		build->Emit(OP_SLL_RI, indexv.RegNum, indexv.RegNum, 2);
-		build->Emit(OP_BOUND, indexv.RegNum, static_cast<PArray*>(Array->ValueType)->ElementCount);
-		build->Emit(OP_LW_R, dest.RegNum, start.RegNum, indexv.RegNum);
+		int shiftbits = 0;
+		while (1 << shiftbits < arraytype->ElementSize)
+		{ 
+			shiftbits++;
+		}
+		assert(1 << shiftbits == arraytype->ElementSize && "Element sizes other than power of 2 are not implemented");
+		build->Emit(OP_BOUND, indexv.RegNum, arraytype->ElementCount);
+		if (shiftbits > 0)
+		{
+			build->Emit(OP_SLL_RI, indexv.RegNum, indexv.RegNum, shiftbits);
+		}
+		build->Emit(arraytype->ElementType->GetLoadOp() + 1,	// added 1 to use the *_R version that
+			dest.RegNum, start.RegNum, indexv.RegNum);			// takes the offset from a register
 		indexv.Free(build);
 	}
 	start.Free(build);
diff --git a/src/thingdef/thingdef_parse.cpp b/src/thingdef/thingdef_parse.cpp
index cc2c71e34b..3119305086 100644
--- a/src/thingdef/thingdef_parse.cpp
+++ b/src/thingdef/thingdef_parse.cpp
@@ -588,7 +588,6 @@ static void ParseUserVariable (FScanner &sc, PSymbolTable *symt, PClassActor *cl
 	sym->Offset = cls->Extend(type);
 	if (symt->AddSymbol(sym) == NULL)
 	{
-		delete sym;
 		sc.ScriptMessage ("'%s' is already defined in '%s'.",
 			symname.GetChars(), cls ? cls->TypeName.GetChars() : "Global");
 		FScriptPosition::ErrorCounter++;