Chapter 3.6, Problem 3.18PP

Practice Problem 3.18 (solution page 332)

Starting with C code of the form

long test (long x, long y, long z) {

long val = ______;

if (______) {

if (______)

val = ______;

else

val = ______;

} else if (______)

val = ______;

return val;

}

GCC generates the following assembly code:

long test(long x, long y, long z)

x in %rdi, y in %rsi, z In %rdx

test:

leaq	(%rdi, %rsi), %rax
addq	%rdx, %rax
cmpq	$-3, %rdi
jge	.L2
cmpq	%rdx, %rsi
jge	.L3
movq	%rdi, %rax
imulq	%rai, %rax

  ret

  .L3:

Movq	%rsi, %rax
imulq	%rdx, %rax

  ret

  .L2:

cmpq	$2, %rdi
jle	.L4
movq	%rdi, %rax
imulq	%rdx, %rax

.L4:

rep; ret

Fill in the missing expressions in the C code.