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| == The Original Code ==
| | #REDIRECT [[ist:Code Generation/Exercise 9]] |
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| Consider the following C code:
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| <c>
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| static unsigned long a = 10;
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| static double *v;
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| extern void *malloc(unsigned long);
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| static double *mkvec(unsigned long n) {
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| if (n < 1) return (double *)0;
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| unsigned long s = sizeof(double);
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| double *v = (double *)malloc(n * s);
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| return v;
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| }
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| double *compute() {
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| v = mkvec(a * 4);
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| for (unsigned long i = 1; i < a; i++)
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| if (v[i] > v[0]) v[i] = 3 * i - 1;
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| return v;
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| }
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| </c>
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| Assume that the size of pointers, '''int''', and '''unsigned long''' is 32 bits and that the size of '''double''' is 64 bits.
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| == Postfix Code ==
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| The Postfix code for the above code is as follows:
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| <asm>
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| </asm>
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| == Compiling and Running ==
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| To compile the Postfix code directly, [[pf2asm]] can be used (assuming a 32-bit architecture):
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| * pf2asm compute.pf
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| * yasm -felf compute.asm
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| [[category:Compilers]]
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| [[category:Teaching]]
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