1
00:00:00,270 --> 00:00:07,080
So guess now we'll be taking a look at this contraflow instructions, contraflow means controlling the

2
00:00:07,080 --> 00:00:08,080
program's flow.

3
00:00:08,520 --> 00:00:12,840
So how we can control the program through changing the instruction point?

4
00:00:13,600 --> 00:00:19,370
Well, I have already said that we cannot change the AP very normal instructions.

5
00:00:19,590 --> 00:00:27,410
That means we cannot change the system very by simply say more to subtract or multiplication, etc.

6
00:00:28,410 --> 00:00:32,120
But there are some instructions that can change the P value.

7
00:00:33,330 --> 00:00:36,470
OK, now let's take a look at that.

8
00:00:36,750 --> 00:00:40,130
Those instructions and these are divided into two types.

9
00:00:40,410 --> 00:00:43,940
Those are unconditional dump and conditional jumps.

10
00:00:44,220 --> 00:00:52,800
So unconditional dumpings, the program flow dumps from a particular point to another point, whatever

11
00:00:52,800 --> 00:00:53,710
the condition may be.

12
00:00:54,690 --> 00:00:59,790
OK, let's check the syntax and the syntax dump space address.

13
00:01:00,240 --> 00:01:08,340
So whenever this instruction has been executed and the program jumps to this address directly, so the

14
00:01:08,340 --> 00:01:13,580
instructions in between the next address and this address will not get executed.

15
00:01:14,160 --> 00:01:19,830
That's why this is called conditional, because we are not taking any condition before the jump and

16
00:01:19,830 --> 00:01:22,580
we are definitely performing a jump to this address.

17
00:01:22,920 --> 00:01:24,550
That's why this is called unconditional.

18
00:01:24,580 --> 00:01:32,130
You now, before we want you see there are conditions, we need to take a look at the Arizona instruction

19
00:01:32,130 --> 00:01:33,800
called COMPAR Instruction.

20
00:01:34,440 --> 00:01:39,550
So this instruction takes to values and compares each of them.

21
00:01:40,590 --> 00:01:43,040
So compare Ebix commonly.

22
00:01:43,350 --> 00:01:50,730
So it takes the Ebix values and the value and then compares the board to the values.

23
00:01:51,000 --> 00:02:00,510
But it does not show the result, but it affects the extended flaks like in 04, Exane Flag four, etc..

24
00:02:00,690 --> 00:02:05,880
So based on those flags, these conditional jumps takes place.

25
00:02:06,600 --> 00:02:13,290
Actually, this company instruction subtracts both of these teachers, but both of these are different

26
00:02:13,290 --> 00:02:21,120
values and then sets the extended fact values based on those extended flag values, these conditional

27
00:02:21,120 --> 00:02:21,990
dump's takes place.

28
00:02:22,560 --> 00:02:24,240
Now, let's take a look at this.

29
00:02:24,750 --> 00:02:31,550
Are these conditional jumps first one is greater than jump greater then.

30
00:02:32,100 --> 00:02:38,100
So after this operation, Ebix, where say Ebix contains 50.

31
00:02:38,610 --> 00:02:43,740
So the next construction will be letting this dump is greater than to the address.

32
00:02:44,850 --> 00:02:47,920
So Fifi's obviously greater than can be.

33
00:02:48,180 --> 00:02:56,970
So the Democrats then will get a ticket and the jumps take place and in the same way jump if greater

34
00:02:56,970 --> 00:02:58,200
than or equal to.

35
00:02:59,980 --> 00:03:10,110
And jump, jump, start, so let's say Ebix contains the value and then I will shoot and then Contee

36
00:03:10,250 --> 00:03:15,700
then the next injection, if we write Jampolis then put this to any address.

37
00:03:16,910 --> 00:03:26,140
Since this dump takes place, if you will, its contents value 30 cents, that is not less than guaranteed,

38
00:03:26,150 --> 00:03:33,500
then this dump will not take place and program continue get normally in a similar way, jump less than

39
00:03:33,500 --> 00:03:36,920
equal, generally stands for less than are equal to.

40
00:03:37,580 --> 00:03:46,070
And finally, James jump is equal if sponte the exact value of this right upfront wanted 2010 only the

41
00:03:46,220 --> 00:03:47,310
jumps takes place.

42
00:03:48,110 --> 00:03:51,250
So these are the basic jumps you need to know.

43
00:03:51,440 --> 00:03:56,140
There are so many dumps based on the external facts.

44
00:03:56,660 --> 00:04:02,600
You you can check on Google that jump jump jumps injection table.

45
00:04:03,230 --> 00:04:12,500
These dumps are very important in the expectation perspective when in the Buffalo first, sometimes

46
00:04:12,500 --> 00:04:21,770
application will take the jump E.S.P Xcode as a backwater, then these jumps comes handy.

47
00:04:23,470 --> 00:04:31,010
OK, guys, that's all some expectation concept now we're going to want to you and let's take a look

48
00:04:31,010 --> 00:04:33,450
at some examples of this now.

49
00:04:33,470 --> 00:04:35,150
Let me create a new file.

50
00:04:40,580 --> 00:04:43,510
Now I'm reading the Groberg, Scott.

51
00:04:47,580 --> 00:04:50,670
Now, I am that in the section.

52
00:04:56,900 --> 00:04:58,940
Now, let's start our chat function.

53
00:05:03,160 --> 00:05:07,840
Now, what I'm going to do is I'm going to move your camera.

54
00:05:09,640 --> 00:05:10,210
30.

55
00:05:13,900 --> 00:05:16,690
More e-books, karma, Condee.

56
00:05:21,600 --> 00:05:34,740
No, what I am going to do is I will say jump blue and so there is no simple label or function in our

57
00:05:35,610 --> 00:05:36,410
assembly code.

58
00:05:36,460 --> 00:05:38,630
No, we are going to create a temp.

59
00:05:38,940 --> 00:05:41,280
This is the temp label and.

60
00:05:43,580 --> 00:05:44,780
OK, actually, right.

61
00:05:47,100 --> 00:05:54,090
OK, let's say some normal instructions, easy cover 50.

62
00:05:58,190 --> 00:06:08,660
Politics, karma, and so whenever my program is executing this court, this is the unconditional jump

63
00:06:08,660 --> 00:06:12,760
that means the program jumps to this level directly.

64
00:06:20,650 --> 00:06:29,830
Now, let's write one instruction after this dump instruction that is moving X comma 40 to show you

65
00:06:29,830 --> 00:06:38,200
guys that year while you will study, because this jump radically changes the education properties level

66
00:06:38,440 --> 00:06:40,780
and this instruction will not get executed.

67
00:06:41,860 --> 00:06:44,050
Now, let's show this.

68
00:06:44,050 --> 00:06:47,620
While not somebody with an awesome.

69
00:06:58,310 --> 00:07:01,290
Down the street with Ali.

70
00:07:12,590 --> 00:07:18,890
Since we're not printing any output, I will be opening likely died during delivery worker.

71
00:07:21,360 --> 00:07:28,970
Now, let me start with the breakpoint at the start function, since we know that there is a short function.

72
00:07:30,570 --> 00:07:31,910
Now let's run our program.

73
00:07:36,070 --> 00:07:47,040
So we are moving the money value, which is OK, one value that is in hexadecimal, so e X contains

74
00:07:47,050 --> 00:07:47,950
one value.

75
00:07:49,570 --> 00:07:56,800
Now we are placing the Dirac's one quarter into e-books, so I'll give an absolutely fine.

76
00:07:57,040 --> 00:07:59,920
Yes, contents one, e-books, contents one.

77
00:07:59,920 --> 00:08:04,090
For now, the instruction takes place.

78
00:08:04,150 --> 00:08:06,610
Jump to this address, which is them.

79
00:08:07,030 --> 00:08:14,380
Now, as you can see, there is a little arrow mark here, arrow pointing to that level.

80
00:08:15,790 --> 00:08:20,990
Now you can see the next section is what we direct onto.

81
00:08:21,220 --> 00:08:28,540
That is we we have we are trying to modify it again, but it won't get more difficult because we are

82
00:08:28,930 --> 00:08:30,030
jumping to the stamp.

83
00:08:30,820 --> 00:08:32,630
So this instruction is kepel.

84
00:08:35,090 --> 00:08:39,310
If they're on this, you can see the exact content still funny.

85
00:08:42,840 --> 00:08:52,890
So this an you see now, this temporary contains some coal, which most an area that is not very much

86
00:08:52,890 --> 00:08:53,350
important.

87
00:08:53,380 --> 00:08:54,720
Now let's cut our program.

88
00:08:54,800 --> 00:08:56,400
Now let's see the conditional jumps.

89
00:09:11,280 --> 00:09:15,420
No, I'm going to compare your ex on.

90
00:09:17,560 --> 00:09:25,100
Thirty six eggs, condensed day, and we are also comparing with 30, it will be equal value.

91
00:09:25,540 --> 00:09:27,250
Now I'm going to jump you.

92
00:09:27,280 --> 00:09:27,790
We call.

93
00:09:35,410 --> 00:09:36,690
Now, let's.

94
00:09:40,470 --> 00:09:47,480
OK, at the same time, we will move to another jumper here to show you are conditional jumps in the

95
00:09:47,490 --> 00:09:48,290
singular program.

96
00:09:49,620 --> 00:09:58,560
I mean, at a time no issues content 50 is a compare you see with.

97
00:10:00,560 --> 00:10:06,380
Hundred since six is going to be less than a hundred.

98
00:10:07,490 --> 00:10:11,700
Now, if I said jump for less, then to test.

99
00:10:14,010 --> 00:10:22,200
Then our program for now that the court at the test level gets a DeCoutere.

100
00:10:24,750 --> 00:10:28,170
Now, let's stop right there, a town called.

101
00:10:36,660 --> 00:10:46,530
OK, guys, now what we have done is we are taking the exit party, so this is so dump president takes

102
00:10:46,530 --> 00:10:48,480
place to the top and bottom.

103
00:10:49,410 --> 00:10:52,840
The core of the template will get a bit more comfy.

104
00:10:52,950 --> 00:10:58,780
And then we are comparing you six hundred since he is less than 100.

105
00:10:59,310 --> 00:11:03,230
This dump takes place and this section will not get executed.

106
00:11:03,540 --> 00:11:06,020
Now, let's see all of this inaudible good.

107
00:11:24,900 --> 00:11:26,880
Now, I'm pushing the break point at the start.

108
00:11:29,450 --> 00:11:30,610
Now, let's run the program.

109
00:11:35,020 --> 00:11:42,930
Now we are moving the value for money in politics and one foot into e-books, just like previous matter,

110
00:11:43,720 --> 00:11:45,170
previous example?

111
00:11:45,580 --> 00:11:49,630
No, we are comparing year with one year since EGS also contains only.

112
00:11:52,140 --> 00:11:59,610
Now the flag is set, you can see the flag here because this combat operation subtracts these values

113
00:11:59,940 --> 00:12:06,770
and checks since these two areas are same, the same production business, the Gedo and the producer,

114
00:12:07,290 --> 00:12:11,600
so difficult districts, this takes the flag.

115
00:12:11,610 --> 00:12:14,040
And you can see there is a Aramark.

116
00:12:14,040 --> 00:12:17,510
Again, it tells us that our jump is successful.

117
00:12:19,260 --> 00:12:22,710
So this more direction did not get executed.

118
00:12:24,210 --> 00:12:26,090
Now we're going to try to do that easy.

119
00:12:26,140 --> 00:12:29,640
It's so easy to do.

120
00:12:29,790 --> 00:12:30,380
That's fine.

121
00:12:31,740 --> 00:12:34,920
No, we are comparing it to 64.

122
00:12:37,920 --> 00:12:49,980
Shin, 64, is greater than the 32 dumpy president, so this is the reason that why don't pay for this

123
00:12:49,980 --> 00:12:56,200
done and the dumped program jumps to this test function global.

124
00:12:58,700 --> 00:13:07,160
And as you can see, politics come out here did not get executed because it contains zero, that means

125
00:13:07,160 --> 00:13:08,900
the jump has successfully taken.

126
00:13:09,650 --> 00:13:18,300
No, we can see the normal Shankaracharya if we can run this program, as it would normally.

127
00:13:19,130 --> 00:13:22,130
So that's all you need to know about the basic jumps.

128
00:13:22,200 --> 00:13:23,990
Yes, I hope we have understood.