Write a C callable assembler function that counts the number of characters in a

Question

Write a C callable assembler function that counts the number of characters in a string. The function should work for any string and character. The address of the string and character to be counted are passed as arguments according to the C function prototype: int count (char *string, char c); Since there are arguments, your assembly function should use a stack frame. It should return the count to the calling C program in %eax. Use 32-bit quantities for all data, chars have only 8 significant bits but they are stored in memory (and on the stack) as 32 bits in "little endian" format. After moving a 32 bit char value from memory to a register, the char value is available in the 8 lsb's, e.g. %al. You are given a C calling program that calls count to count the number of a user entered character in a user entered string and prints the result. The C code "driver" is in countc.c. Put your assembly code in counts. Then build it using the same makefile by invoking "make A=count".

Explanation / Answer

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then call it like this:

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