Consider the following C/C++ code segment:
_int64 g = 4;
_int64 min(_int64 a, _int64 b, _int64 c) {
_int64 v = a;
if (b < v)
v = b;
if (c < v)
v = c;
return v;
}
_int64 p(_int64 i, _int64 j, _int64 , k, _int64 l) {
return min(min(g, i, j), k, l);
}
_int64 gcd(_int64 a, _int64 b) {
if (b == 0) {
return a;
} else {
return gcd(b, a % b);
}
}
_int64 q(_int64 a, _int64 b, _int64 c, _int64 d, _int64 e) { _int64 sum = a + b + c + d + e;
printf("a = %I64d b = %I64d c = %I64d d = %I64d e = %I64d sum = %I64d\n", a, b, c, d, e, sum); return sum;
}
Q1. Translate the code segment above into x64 assembly language using the basic code generation strategy outlined in lectures. The % operation can be implemented using the x64 cqo and idiv instructions. Assume you must supply shadow space for the calls to function min in p.
Q2. Draw a diagram showing the state of the stack at its maximum depth during the calculation of gcd(14, 21).
Q3. Using Visual Studio (or similar), create an x64 console application with files t2.h and t2.asm containing the x64 assembly language for min, p, gcd and q. Use t2Test.cpp to test min, p, gcd and q. Please note that the source code provided may need to be modified to work with the development environment you use.
Q4. Write a function qns() which simply calls printf(“qns\n”) with and without allocating shadow space. Determine what happens when qns() is executed with and without shadow space (provide a screen snapshot).
CSU34021 Tutorial 2 © 2019 jones@scss.tcd.ie
Submit your answer, which should include code listings and a snapshot of the console window showing evidence that your program works, via Blackboard. The deadline is on the course web page.
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