Assembly code program

CSE2312-001 (Spring 2021) Homework #3

Notes:

- All numbers are in base-10 unless otherwise noted. - If part of a problem is not solvable, explain why in the answer area. - Print out the form and handwrite your answers in the spaces below. - Place the hw3.s file and the scanned answers to problem 1 in a single zip file

with name lastname_hw3.zip, where lastname is your last name as listed in MyMav.

- Submit the single zip file to Canvas before 11:59:00pm on Thursday, April 8. - Make sure that the code follows the procedure call standards for ARM

architecture (see IHI0042F section 5.1), with emphasis on this requirement: “A subroutine must preserve the contents of the registers r4-r8, r10, r11 and SP (and r9 in PCS variants that designate r9 as v6).” (in other words, push and pop R4-11 if you need to use them, as shown in the vector.s examples in class)

1. Suppose that BUSINESS7 structure is defined as:

typedef struct _BUSINESS7 { uint32_t taxId; char name[27]; char direction; char street[35]; uint32_t addNo; char city[30]; char state[3]; uint32_t zip; } BUSINESS7;

Show the relative offset of each field in the structure from the beginning of the structure for the unpacked (default alignment) case:

Show the relative offset of each field in the structure from the beginning of the structure for the packed case:

2. Write assembly functions that implement the following C functions:

a. bool isStrEqual(const char str1[], const char str2[]) // returns true (1) if the strings match, false (0) otherwise

b. void strConcatenate(char strTo[], const char strFrom[]) // adds the contents of string strFrom to strTo // note: strTo must have enough space to hold the contents of strFrom and strTo

c. int32_t sumS32(const int32_t x[], uint32_t count) // returns sum of the values in the array (x) containing count entries.

d. uint32_t countAboveLimit(const int32_t x[], int32_t limit, uint32_t count) // returns number of values in the array (x) containing count entries that are > limit

e. void leftString(char * strOut, const char * strIn, uint32_t length) // input: array (strIn) containing the input string, and the number of characters to extract (length) // output: array (strOut) containing up to, but not exceeding length number of strIn characters from the start of the array // strIn = ‘abcdef’, length = 5 → returns strOut = ‘abcde’ // strIn = ‘abcdef’, length = 7 → returns strOut = ‘abcdef’

f. int32_t find2ndMatch(const char strIn[], const char strMatch[]) // input: array (strMatch) containing the string to find in the array (strIn) // output: returns the offset within str of the 2nd occurrence of strMatch or -1 if not found

g. void sortAscendingInPlace (uint32_t x[], uint32_t count) // input: array (x) containing count entries // output: array (x), with the values sorted in ascending order

h. int16_t decimalStringToInt16(const char * str) // convert the null-terminated string (str) to a signed 16-bit integer // treat the string as representing a decimal number // if a character other than 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or – is present or the value is out of range, return 0 // the -, if present after the first character should cause the function to return 0

i. uint8_t hexStringToUint8(const char * str) // convert the null-terminated string (str) to an unsigned 8-bit integer // treat the string as representing a hexadecimal number

// if a character other than 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, or F is present or the value is too large, return 0.

j. int32_t findCityAligned (const char city[], const BUSINESS7 business[], uint32_t count) // returns the index of the first entry in the array (business) containing count entries which matches the requested city. If the city is not found, return a value of -1. You can assume that C default alignment is used for this problem.

k. int32_t findCityPacked (const char city[], const BUSINESS7 business[], uint32_t count) // returns the index of the first entry in the array (business) containing count entries which matches the requested city. If the city is not found, return a value of -1. You can assume that C packing is used for this problem.

Write the solution of each of these functions in a single file hw3.s with functions being callable from a C program. You do not need to send the .c file.