Starting Out with C++ from Control Structures to Objects (9th Edition)
9th Edition
ISBN: 9780134498379
Author: Tony Gaddis
Publisher: PEARSON
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Expert Solution & Answer
Chapter 1, Problem 25RQE
Program Description Answer
The variable must be “Declared or Defined” before it must be used in a program.
Expert Solution & Answer
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Students have asked these similar questions
Match each of the assembler routines on the left with the equivalent C function on
the right. Write the name of the label (e.g., foo) to the right of the corresponding
function. Note: shrq is the logical right shift instruction, and sarq is the arithmetic
right shift instruction.
foo1:
leaq
0(,%rdi, 8), %rax
long choice1 (long x)
{
ret
return x -
8 >8;
foo3:
}
movq
sarq
%rdi, %rax
$8, %rax
long choice4 (long x)
ret
{
return x*256;
}
foo4:
long choice5 (long x)
leaq
-8 (%rdi), %rax
{
ret
return x-8;
}
long choice6 (long x)
foo5:
{
leaq
-8 (%rdi), %rax
return x+8;
shrq
$63, %rax
}
ret
Given the variables and code in the text below, identify where in memory they will
live once the code is compiled.
1 char
big_array [1L<<24]; /* 16 MB */
2 GB *
:/
2 char huge_array [1L<<31]; /*
3
4 int global = 0;
5
6 int useless () { return 0; }
7
8 int main()
9 {
10
void *p1, p2, *p3, *p4;
int local =
0;
malloc (1L << 28); /* 256 MB *,
11
12
p1
13
p2
=
malloc (1L << 8);
/* 256 B *
14
p3
15
p4
=
malloc (1L << 32);
malloc (1L << 8);
/* 4
GB *
*/
/* 256
B */
16 }
Note: *pN is the thing at which pN points.
1. big_array
2. huge_array
3. global
4. useless
5. void* p1
6. *p1
7. void* p2
8. *p2
9. void* p3
10. *p3
11. void* p4
12. *p4
The next problem concerns the following C code:
/copy input string x to buf */
void foo (char *x) {
char buf [8];
strcpy((char *) buf, x);
}
void callfoo() {
}
foo("ZYXWVUTSRQPONMLKJIHGFEDCBA");
Here is the corresponding machine code on a Linux/x86 machine:
0000000000400530 :
400530:
48 83 ec 18
sub
$0x18,%rsp
400534:
48 89 fe
mov
%rdi, %rsi
400537:
48 89 e7
mov
%rsp,%rdi
40053a:
e8 di fe ff ff
callq
400410
40053f:
48 83 c4 18
add
$0x18,%rsp
400543:
c3
retq
400544:
0000000000400544 :
48 83 ec 08
sub
$0x8,%rsp
400548:
bf 00 06 40 00
mov
$0x400600,%edi
40054d:
e8 de ff ff ff
callq 400530
400552:
48 83 c4 08
add
$0x8,%rsp
400556:
c3
This problem tests your understanding of the program stack. Here are some notes to
help you work the problem:
⚫ strcpy(char *dst, char *src) copies the string at address src (including
the terminating '\0' character) to address dst. It does not check the size of
the destination buffer.
• You will need to know the hex values of the following characters:
Chapter 1 Solutions
Starting Out with C++ from Control Structures to Objects (9th Edition)
Ch. 1.2 - Why is the computer used by so many different...Ch. 1.2 - List the five major hardware components of a...Ch. 1.2 - Internally, the CPU consists of what two units?Ch. 1.2 - Prob. 1.4CPCh. 1.2 - Prob. 1.5CPCh. 1.2 - Prob. 1.6CPCh. 1.2 - Prob. 1.7CPCh. 1.2 - Prob. 1.8CPCh. 1.2 - What do you call a program that performs a...Ch. 1.2 - Word processing programs, spreadsheet programs,...
Ch. 1.3 - What is an algorithm?Ch. 1.3 - Why were computer programming languages invented?Ch. 1.3 - Prob. 1.13CPCh. 1.3 - Prob. 1.14CPCh. 1.3 - Prob. 1.15CPCh. 1.3 - Prob. 1.16CPCh. 1.3 - Prob. 1.17CPCh. 1.5 - Prob. 1.18CPCh. 1.5 - Prob. 1.19CPCh. 1.5 - Describe the difference between a program line and...Ch. 1.5 - Prob. 1.21CPCh. 1.5 - What happens to a variables current contents when...Ch. 1.5 - What must take place in a program before a...Ch. 1.5 - Prob. 1.24CPCh. 1.7 - What four items should you identify when defining...Ch. 1.7 - Prob. 1.26CPCh. 1.7 - What is a hierarchy chart?Ch. 1.7 - Prob. 1.28CPCh. 1.7 - Describe what a compiler does with a programs...Ch. 1.7 - Prob. 1.30CPCh. 1.7 - Is a syntax error (such as misspelling a key word)...Ch. 1.7 - What is the purpose of testing a program with...Ch. 1.7 - Briefly describe the difference between procedural...Ch. 1 - Prob. 1RQECh. 1 - What is the difference between system software and...Ch. 1 - Prob. 3RQECh. 1 - Why must programs written in a high-level language...Ch. 1 - Why is it easier to write a program in a...Ch. 1 - Prob. 6RQECh. 1 - Prob. 7RQECh. 1 - Prob. 8RQECh. 1 - The job of the ________ is to fetch instructions,...Ch. 1 - Internally, the CPU consists of the _______ and...Ch. 1 - Prob. 11RQECh. 1 - The two general categories of software are...Ch. 1 - A program is a set of _______.Ch. 1 - Prob. 14RQECh. 1 - _______ is the only language computers really...Ch. 1 - __________ languages are close to the level of...Ch. 1 - ________ languages are close to the level of the...Ch. 1 - Prob. 18RQECh. 1 - Words that have special meaning in a programming...Ch. 1 - Prob. 20RQECh. 1 - Prob. 21RQECh. 1 - __________ characters or symbols mark thebeginning...Ch. 1 - Prob. 23RQECh. 1 - Prob. 24RQECh. 1 - Prob. 25RQECh. 1 - Prob. 26RQECh. 1 - __________ is information a program gathers from...Ch. 1 - __________is information a program sends to the...Ch. 1 - Prob. 29RQECh. 1 - Available Credit The following steps should be...Ch. 1 - Sales Tax Design a hierarchy chart or flowchart...Ch. 1 - Account Balance Design a hierarchy chart or...Ch. 1 - The variable x starts with the value 0. The...Ch. 1 - The variable j starts with the value 10. The...Ch. 1 - The variable a starts with the value 1. The...Ch. 1 - Find the Error 36. The following pseudocode...
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