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A-1 Declarations, Expressions, and Assignments
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        Compile the following program (file  A-1.c) and observe the GIMPLE dumps
        and answer  the questions below. If  you manage to finish  all questions
        quickly try to attempt the optional problem.

        Source file : A-1.c
        Compilation : gcc-4.7.2 -c -fdump-tree-gimple A-1.c
        View result : vi -O A-1.c A-1.c.*.gimple
        Clear dumps : rm -f A-1.c.* A-1.o

Program
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	int Z;

	void main()
	{
		int a, b, c;
		int p = 6;
		int q;
		double r;

		a = 10;
		b = 20;
		c = a * b + 25;
		p = 6;
		q = Z;
		r = 34.5;
		Z = r;
		Z = Z + 1;
	}


Questions
---------

        1   How  do the  declarations  look in  the  GIMPLE? Specifically,  what
            happens to multiple  variables declared and initialized  on the same
            line? What happens to global declaration [int Z]?

        2   How are complex  expressions such as [c  = a * b +  25] broken down?
            Can you  determine a  rule as  to when  temporary variables  will be
            introduced?

        3   How are  floats/doubles represented in  GIMPLE? What happens  when a
            float/double is assigned to an integer in [Z = r]?

        4   How  are reads/writes  to the  global variable  Z performed?  Why is
            there a temporary introduced  for the statement [Z = Z  + 1] but not
            for the statements [q = Z] or [Z = p]?

            
Optional Problem
----------------

        Try to understand the underlying GIMPLE representation by looking at the
        RAW dumps:

        Compilation : gcc-4.7.2 -c -fdump-tree-gimple-raw A-1.c
        View result : vi -O A-1.c A-1.c.*.gimple