Description

CSE 310: Compiler Sessional
Assignment 4 Intermediate Code Genaration

1 Introduction
In the previous assignment, we have performed syntax and semantic analysis of a source code written in a subset of C language. In this assignment you have to generate intermediate code for a source program having no error. That means if your source code does not contain any error, that was to be detected in the previous offline, you will have to generate intermediate code for the source code. We have picked 8086 assembly language as our intermediate representation.
2 Tasks
You have to complete the following tasks in this assignment.
2.1 Intermediate Code Generation
• Add a field ‘code’ in SymbolInfo Class. As each of your non-terminal has a SymbolInfo pointer as attribute, you can propagate code for different portion using this newly added field.
• To generate assembly code for conditional statements and loops, define two functions named newLabel() and newTemp() where newLabel will generate a new label on each call and newTemp will generate a new temporary variable.
• Write a procedure for println(ID) function and call this procedure in your assembly code whenever you reduce a rule containing println.
• You have to declare the variables declared in the source code in the data segment of the assembly code. As the variable name can be same in different scope, you can concatenate the scope id with the variable name to make it unique.
• Handle the function call and return using stack.
2.2 Optimization
You have to do some peephole optimization works after intermediate code is generated. To do this you will take pair of consecutive instructions in the generated code and remove the following redundancy:
• Redundant mov instruction like
mov ax, a mov a, ax
In this case the second mov instruction can be omitted.
3 Input
The input will be a C source program in .c extension. File name will be given from command line.
4 Output
In this assignment, there will be two output file. One file, log.txt, that will contain line count, error count and any lexical, syntax or semantic errors. It would be just like your previous log file except that you don’t need to print productions and symbol table. Another file, code.asm will contain the generated assembly code before performing optimization. The last file optimizedCode.asm will contain the assembly code after optimization.
You are also encouraged to show your assembly code by running it in any emulator.
5 Submission
6 Submission
All Submission will be taken via moodle. Please follow the steps given below to submit you assignment.
1. In your local machine create a new folder which name is your 7 digit student id.
2. Put the lex file named as <your_student_id>.l and yacc file named as <your_student_id>.y containing your code. Also put additional c file or header file that is necessary to compile your lex file. Do not put the generated lex.yy.c file or executable file in this folder.
3. Compress the folder in a zip file which should be named as your 7 digit student id.