- Just some stuff.

SVN r1878 (scripting)

src/zscript/vmbuilder.h

@@ -0,0 +1,77 @@
+#ifndef VMUTIL_H
+#define VMUTIL_H
+
+#include "vm.h"
+
+class VMFunctionBuilder
+{
+public:
+	// Keeps track of which registers are available by way of a bitmask table.
+	class RegAvailability
+	{
+	public:
+		RegAvailability();
+		int GetReg(int count);		// Returns the first register in the range
+		void ReturnReg(int reg, int count);
+		void Dump();
+
+	private:
+		VM_UWORD Used[256/32];		// Bitmap of used registers (bit set means reg is used)
+		int MostUsed;
+
+		friend class VMFunctionBuilder;
+	};
+
+	VMFunctionBuilder();
+	~VMFunctionBuilder();
+
+	VMScriptFunction *MakeFunction();
+
+	// Returns the constant register holding the value.
+	int GetConstantInt(int val);
+	int GetConstantFloat(double val);
+	int GetConstantAddress(void *ptr, VM_ATAG tag);
+	int GetConstantString(FString str);
+
+	// Returns the address of the newly-emitted instruction.
+	size_t Emit(int opcode, int opa, int opb, int opc);
+
+	// Write out complete constant tables.
+	void FillIntConstants(int *konst);
+	void FillFloatConstants(double *konst);
+	void FillAddressConstants(FVoidObj *konst, VM_ATAG *tags);
+	void FillStringConstants(FString *strings);
+
+	// PARAM increases ActiveParam; CALL decreases it.
+	void ParamChange(int delta);
+
+	// Track available registers.
+	RegAvailability IntRegisters;
+	RegAvailability FloatRegisters;
+	RegAvailability AddressRegisters;
+	RegAvailability StringRegisters;
+
+private:
+	struct AddrKonst
+	{
+		int KonstNum;
+		VM_ATAG Tag;
+	};
+	// These map from the constant value to its position in the constant table.
+	TMap<int, int> IntConstants;
+	TMap<double, int> FloatConstants;
+	TMap<void *, AddrKonst> AddressConstants;
+	TMap<FString, int> StringConstants;
+
+	int NumIntConstants;
+	int NumFloatConstants;
+	int NumAddressConstants;
+	int NumStringConstants;
+
+	int MaxParam;
+	int ActiveParam;
+
+	TArray<VM_UBYTE> Code;
+};
+
+#endif