EE 109 Homework 5 Name: ___________________________________________ Due: Note: Attach all work to receive full credit Score: ________ HLL to Assembly Translation 1.) Translate the following C code statements to an equivalent assembly language implementation. short data[20]; ... for(int i=0;i < 20; i++){ data[i] = data[i] + 5; } // let i be stored in $t0 data .space .text ... la add li L0: slt L1: beq_ L2: sll L3: add L4: lh L5: addi L6: sh L7: addi L8: b L9: ... x y int *x, *y; ... if(*x >= 10 && *y < 5) code A else if (*x < 10 || *y > 5) code B else code C ... L1: L2: L3: L4: L5: L6: L7: L8: .space .space ... la la addi addi lw lw lw lw blt bge_ Code A b blt_ ble_ Code B b Code C ... 40 or 0x28___ $s0,data $t0,$zero_,$zero $t4,_20 or 0x14__ $t1,$t0_,$t4 $t1,$zero,_L9___ $t2,$t0,_1__ $s1,$s0_,$t2 $t3,0($s1)__ $t3,$t3_,5 $t3,0($s1)__ $t0,$t0,1 _L0_____ 4 4 $s0,x $s1,y $t0,$zero_,10 $t1,$zero_,5 $s2,0($s0) $s3,0($s1) $t2,0($s2)_ $t3,0($s3)_ $t2_,$t0,_L3___ $t3,$t1_,_L3___ instructions L8___________ $t2,$t0,_L5___ $t3,$t1,_L7___ instructions _L8__________ instructions Subroutines and Assembly 2.) In addition to passing arguments in registers or by using the stack, another possible method (that no one would ever use) is to provide space for the arguments in the code itself (though you should note that this code will NOT assemble using MARS because it does not allow data directives in the text section). However, pleas study the code below to understand how this method works and answer the given questions. Show any work on an extra page and submit that with your homework. SHOW ALL VALUES in HEX. Assume that the .data section starts at 0x10010000. a.) Before execution of “jal AVG”, what are the contents of $t0, $t1, and $t2. b.) Before execution of “sra $v0,$v0,1”, what are the contents of $v0, $t3, & $ra? c.) After program execution, what are the contents of $ra and the word at address RES. 0x400000 0x400008 0x40000c 0x400010 0x400014 0x400018 0x40001c 0x400020 0x400024 0x40002c 0x400030 0x400038 .data VALS: .half 0xbead, 0xface RES: .space 4 .text la $t0,VALS lh $t1,($t0) lhu $t2,2($t0) sll $t2,$t2,16 or $t2,$t1,$t2 jal AVG .word -2 .word -6 la $t4,RES sw $v0,($t4) li $v0,10 syscall AVG: lw lw add sra addi jr $v0,($ra) $t3,4($ra) $v0,$v0,$t3 $v0,$v0,1 $ra,$ra,8 $ra a.)$t0 = 0x10010000 $t1 = 0xffffbead $t2 = 0xffffbead b.)$v0 = 0xfffffff8 $t3 = 0xfffffffa $ra = 0x0040001c c.)$ra = 0x00400024 M[RES] = 0xfffffffc
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