private int computeStructOffsetFromStackOffset(int stackOffset, boolean doCheckDefinedOffset) {
		int structOffset = stackOffset + negativeLength - parameterOffset; // parameterOffset - negativeLength + stackOffset;
		if (doCheckDefinedOffset &&
			(structOffset < 0 || structOffset >= wrappedStruct.getLength())) {
			throw new IllegalArgumentException("Offset " + getHexString(stackOffset, true) +
				" is not a defined within the stack frame");
		}
		return structOffset;
	}
Get a formatted signed-hex value
@param offset the value to be formatted
@param showPrefix if true the "0x" hex prefix will be included
@return formatted signed-hex value
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/stackeditor/StackFrameDataType.java