Consider the following code segment:
x = u - t;
y = x * v;
x = y + w;
y = t - z;
y = x * y;
The minimum number of total variables required to convert the above code segment to static single assignment form is

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Solution

$r_{1} = r_{2} - r_{3}; r_{4} = x * r_{5};$

$x_{6} = y + r_{7}; r_{8} = r_{3} - r_{9};$

$r_{10} = x * y;$

In static single assignment form 1 temporary register will be assign to only 1 variable and every variable is defined before it is used (we have to assign the register at a time of define the variable) throughout the code segments. So here 10 variables are needed.

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Consider the following code segment: x = u - t; y = x * v; x = y + w; y = t - z; y = x * y; The minimum number of total variables required to convert the above code segment to static single assignment form is

Consider the following code segment:
x = u - t;
y = x * v;
x = y + w;
y = t - z;
y = x * y;
The minimum number of total variables required to convert the above code segment to static single assignment form is