38: Quiz#5: Postfix code , Name: ___________________________

• CS 340, Fall 2019, York College of Pennsylvania
• 41, 20 points, 2019-10-09 (at start of class)

The following provides some background on the quiz.

• Postfix traversal to generate code

The quiz requires you to do a manual simulation of stack-based code execution using stack-based code in postfix form, as in the following.

• Stack-based code execution

Use the provided postfix code and values for the variables in the postfix code.

• The first line should be "init the stack".
• Write the variable or operator, left justified on a separate line.
• On the following line(s) for each variable or operator, write the actions(s), for that variable or operator.
• pushes should have the form "push expression as value".
• pops should have the form "pop value as variable".
• Use reg1 and reg2 as temporary registers.
• The last line should indicate the result.

The variable values to be used will be provided. (Note: This was done in class when the exam was given and this text added after the exam).

Postfix code list: omitted
Variable values: (omitted)

Example: (using the running example)

Postfix code:

Let x be 1 and y be 0

Sequence: (you should write something like the following, depending on the expression provided).