WEBVTT 00:00.590 --> 00:01.730 Hello, my name is Typhoon. 00:01.730 --> 00:06.500 And in this lecture we will delve into the fascinating world of assembly language programming. 00:06.530 --> 00:11.930 In this lecture, we will explore the intricacies of some fundamental arithmetic operations within our 00:11.930 --> 00:12.680 program. 00:13.330 --> 00:22.090 Now get ready to witness the magic of incrementing decrementing shifting, multiplying and dividing. 00:22.120 --> 00:29.200 And throughout this lecture, we will dissect each of these operations step by step, unraveling the 00:29.200 --> 00:34.110 code line by line to understand how they work at their core. 00:34.120 --> 00:41.200 And we will be working with registers, memory and functions to manipulate numbers and display their 00:41.200 --> 00:42.010 results. 00:42.040 --> 00:48.400 The assembly language offers us a such a unique perspective into the inner workings of computers, low 00:48.400 --> 00:56.110 level operations, providing insights into how calculations are executed at the hardware level. 00:56.140 --> 01:02.950 Starting with incrementing, we will see how a single instruction can add one to a number and transform 01:02.950 --> 01:04.220 its value from there. 01:04.240 --> 01:12.190 We will move to Decrementing where we will learn how subtraction plays a role in reducing values. 01:12.950 --> 01:13.550 Shifting. 01:13.550 --> 01:19.970 Our next venture allows us to multiply and divide by powers of two throughout bit manipulation. 01:20.600 --> 01:26.930 And this demonstrates how computer architects use clever tricks to optimize certain operations. 01:26.930 --> 01:30.800 And our journey continues with multiplication and division. 01:30.800 --> 01:36.800 By diving into these operations, we will understand how computers perform these fundamental arithmetic 01:36.830 --> 01:42.620 tasks and how we can harness their power in assembler language. 01:42.620 --> 01:47.510 So fasten your belts as we embark on this enriching journey. 01:47.510 --> 01:54.710 But also by the end of this lecture you will have a solid grasp grasp of incrementing decrementing shifting, 01:54.710 --> 01:58.940 multiplying and dividing, working in assembly language. 01:59.210 --> 02:05.570 Now let's dive in to explore the intricate dance between software and hardware that makes these operations 02:05.570 --> 02:06.380 possible. 02:06.380 --> 02:14.060 But first we will write the incrementing incrementing side of our program. 02:14.060 --> 02:18.140 Here we will load the value of number one to rax. 02:18.140 --> 02:19.370 So move. 02:20.110 --> 02:21.410 Move rax. 02:23.600 --> 02:26.960 Uh, number one inside braces. 02:26.990 --> 02:31.660 Now we will use I and C racks. 02:32.220 --> 02:36.630 This we use this for incrementing rex by one. 02:36.650 --> 02:40.220 We will store the result in result I. 02:40.950 --> 02:41.640 Move. 02:42.980 --> 02:44.750 The result, I result. 02:46.660 --> 02:48.100 And racks. 02:48.490 --> 02:50.620 We will display the result here. 02:50.620 --> 02:53.050 So display the result. 02:54.690 --> 02:56.940 And after that we will move the. 02:58.670 --> 02:59.900 Fmt int. 02:59.930 --> 03:03.260 This is for a local address of format. 03:03.290 --> 03:10.040 Uh, we are loading the address of format string to die and now we will load the address of message 03:10.040 --> 03:10.880 to RSI. 03:11.240 --> 03:14.600 RSI The address of messages. 03:16.760 --> 03:19.130 I nci here. 03:19.160 --> 03:19.910 Number one. 03:20.120 --> 03:21.950 Number one, incremented. 03:23.160 --> 03:23.460 I. 03:24.630 --> 03:25.580 Move. 03:26.280 --> 03:27.140 Move! 03:27.150 --> 03:28.980 RDX. 03:29.940 --> 03:30.990 Result, I. 03:31.020 --> 03:35.970 Here we are loading the value of result i to RDX. 03:36.000 --> 03:40.290 Now we will clear the rax register which is returning the value. 03:41.050 --> 03:46.000 And now we will call the printf to display the formatted message. 03:46.030 --> 03:50.470 Now we will develop the decrementing here. 03:50.470 --> 03:55.240 So we will move load the value of number one to rax. 03:57.210 --> 03:57.990 Move. 04:02.910 --> 04:03.780 Racks. 04:04.730 --> 04:07.040 The number one. 04:08.070 --> 04:19.110 Uh, these here we in incrementing we use I and C and here we will use the c here rax this is for decrementing 04:19.110 --> 04:20.730 rax by one. 04:20.820 --> 04:30.060 We will use move here result i here rax we are storing the result in result i and now we will need to 04:30.060 --> 04:31.470 display the results. 04:31.470 --> 04:34.620 So display the result. 04:34.680 --> 04:43.620 Now we will use the load load address of format string to move the i fmt int. 04:45.830 --> 04:46.100 Right? 04:46.110 --> 04:46.730 Yeah. 04:47.090 --> 04:49.760 Fmt it mov rsi. 04:50.990 --> 04:52.850 Uh, Daisy here. 04:54.100 --> 04:55.780 There are string. 04:56.570 --> 04:57.500 Start. 04:58.860 --> 04:59.430 Let's see. 05:02.230 --> 05:02.530 E. 05:02.530 --> 05:03.040 A. 05:03.040 --> 05:03.880 S. 05:03.880 --> 05:06.070 C, d, a c. 05:06.460 --> 05:08.350 And now. 05:09.620 --> 05:12.890 We will use load the value of result I to RDX. 05:12.890 --> 05:15.260 Move RDX. 05:16.190 --> 05:28.050 Result I here and now we will move the racks zero to clear the racks register and we will call the printf. 05:28.730 --> 05:30.590 And now we will need to shift. 05:30.770 --> 05:33.530 Use the shift arithmetic left here. 05:33.830 --> 05:34.820 Shift. 05:35.240 --> 05:39.530 Left shift our metric. 05:42.050 --> 05:42.560 Are. 05:45.240 --> 05:47.190 Arithmetic left. 05:48.000 --> 05:53.010 So here what we're going to do is we will load the value of number one to Rax. 05:53.010 --> 06:00.030 So move rax number one cell rax. 06:00.910 --> 06:01.480 Two. 06:01.510 --> 06:04.300 I will explain all of this newly. 06:07.510 --> 06:08.020 Here. 06:08.020 --> 06:09.280 So move. 06:10.050 --> 06:21.480 Result I here and Rex here we shift Rex left by shifting the Rex left by two bits, which is me, which 06:21.480 --> 06:23.760 means multiplying by four. 06:23.790 --> 06:35.070 Here we are storing the result in result I here and now we will need to display display the result. 06:35.100 --> 06:36.090 Now we are. 06:36.240 --> 06:36.510 We are. 06:36.660 --> 06:40.640 We need to load the address of format string to r.d.e. 06:40.680 --> 06:42.060 So move the. 06:42.980 --> 06:46.820 Are the I fmt integer. 06:48.390 --> 06:50.160 Move the RSI. 06:54.540 --> 06:58.290 Sally, which we defined previously in data section. 07:00.570 --> 07:04.740 Number one shift left to which is multiplying by four. 07:05.590 --> 07:18.730 And move RDX here, which is, uh, for loading the value of result result i to RDX result I to RDX. 07:18.760 --> 07:25.420 Now we will move the racks so we will clear the racks register which is returning the value and we will 07:25.420 --> 07:28.000 lastly call the printf. 07:28.030 --> 07:29.140 Printf. 07:30.100 --> 07:33.060 And after that we will need to shift arithmetic. 07:33.070 --> 07:37.030 We will we will need to write shift arithmetic right here. 07:37.300 --> 07:39.580 So shift. 07:40.920 --> 07:43.770 Arithmetic right now. 07:43.770 --> 07:44.070 We will. 07:44.070 --> 07:44.520 Right. 07:44.550 --> 07:45.360 Move. 07:47.710 --> 07:48.310 Move. 07:49.900 --> 07:59.860 Tracks, number one, which is for loading, not bomber number one, and this is for loading the value 07:59.860 --> 08:02.140 of number one to racks. 08:02.140 --> 08:11.410 So s a R for shifting racks right by two bits, which is arithmetic shift, which is this. 08:11.410 --> 08:24.160 This here is divided by four here shift of SA racks and two and move. 08:25.920 --> 08:31.560 Result I here registered result in a result I now display. 08:31.590 --> 08:33.720 Display the result. 08:34.020 --> 08:34.890 Move. 08:35.880 --> 08:44.400 RTI Fmt which is load which is assembly code here loads the address of format string to RTI. 08:45.970 --> 08:50.980 MOV rsi sa i here. 08:51.010 --> 08:54.280 This is followed the address of message to RSI. 08:54.700 --> 09:05.050 Now we will load the value of result I to RDX, move the RDX to result I here and now we will move the 09:05.050 --> 09:14.920 rax we will clear the rax basically call printf again print f they're calling printf to display the 09:14.920 --> 09:16.210 formatted message. 09:16.210 --> 09:19.930 We just need to now write the shift arithmetic. 09:19.930 --> 09:21.610 Right with sign expression. 09:21.880 --> 09:26.410 Uh, and as well we will write displaying the result as well. 09:26.410 --> 09:31.330 And we will write, multiply, divide and we will end the program. 09:31.330 --> 09:34.600 And then in next lecture we will try to analyze it. 09:34.600 --> 09:39.640 So there's just 1 or 2 functionalities, uh, to be written in this lecture. 09:39.640 --> 09:42.010 And after that we are done. 09:42.460 --> 09:45.590 So what we can we have already written the shift arithmetic. 09:45.590 --> 09:48.440 Right now we need to write the shift arithmetic, right? 09:48.440 --> 09:50.420 With sign extension. 09:52.860 --> 09:53.270 Here. 09:54.500 --> 09:55.220 Shift. 09:56.990 --> 09:58.310 Arithmetic. 09:58.310 --> 09:59.270 Right. 10:00.000 --> 10:02.510 With sign extension. 10:02.520 --> 10:03.660 This is for now. 10:03.660 --> 10:08.730 We will load the value of the move. 10:11.610 --> 10:17.070 Now we will move racks to negative number. 10:19.030 --> 10:22.690 Which is for loading the value of negative number to racks. 10:23.380 --> 10:25.450 Remember, this is a negative number for now. 10:25.960 --> 10:27.400 Now we will use a. 10:28.470 --> 10:37.680 As a ah, this is for shifting the racks by two bits with sign extension, which is this is also called 10:37.680 --> 10:39.480 the arithmetic shift. 10:39.600 --> 10:43.170 And after that we will store the result in result. 10:43.200 --> 10:44.570 I result. 10:44.700 --> 10:45.020 Yes. 10:45.030 --> 10:45.450 Result. 10:45.480 --> 10:48.420 I basically so result. 10:50.680 --> 10:55.600 Racks and now we will need to display the result here. 10:55.600 --> 11:00.640 So move or die fmt int. 11:02.150 --> 11:03.020 Which is followed. 11:03.350 --> 11:05.220 Address of format string two. 11:05.750 --> 11:08.450 Now we will move the RSI to. 11:08.490 --> 11:09.110 Sorry. 11:09.530 --> 11:10.490 This is for load. 11:10.490 --> 11:13.640 The address of address of message to RSI. 11:14.340 --> 11:18.380 Uh, remember, we have defined something like, uh, here. 11:18.410 --> 11:19.550 Number one shift. 11:19.550 --> 11:19.970 Right? 11:19.970 --> 11:23.690 Two dividing by four with sign expression. 11:24.730 --> 11:24.990 It. 11:25.140 --> 11:29.860 It will understand it better when we create the output for this run the program. 11:30.250 --> 11:31.690 And after that. 11:33.290 --> 11:34.370 Uh, we need to. 11:35.810 --> 11:39.980 Lord the value of result I to move. 11:41.050 --> 11:50.740 MOV rdx is result i here and move now we will move the rax which is zero. 11:50.740 --> 11:57.220 We will clear the rax register and we will call the printf as we always do. 11:57.400 --> 12:02.230 And now we will also multiply it, divide it and that's it. 12:02.230 --> 12:08.260 So multiplication will be much easier than division and you will see why. 12:08.650 --> 12:11.350 So multiply. 12:11.380 --> 12:12.640 So move. 12:13.540 --> 12:14.450 Racks. 12:16.050 --> 12:17.040 Number one. 12:17.040 --> 12:19.920 Here we are loading the value of number one to racks. 12:19.950 --> 12:23.580 We will email here, use email keyword. 12:24.570 --> 12:25.860 Number two. 12:26.070 --> 12:26.590 Here we are. 12:26.610 --> 12:32.190 Multiply we are telling the assembler to multiply rax with the value of number two, which is this is 12:32.190 --> 12:40.230 the 64 bit multiplication and we will use the move here to store the result in result. 12:40.260 --> 12:47.370 I in order to do that we will use the result I here and after that we will tell rax and now we will 12:47.370 --> 12:49.500 need to display the result here. 12:49.500 --> 12:56.340 Display the result mov rda you already know how to display the result here. 12:56.490 --> 12:59.400 Fmt int mov rsi. 13:01.980 --> 13:03.600 MOV RDX. 13:05.370 --> 13:09.790 Result II which is loading the value of result I to RDX. 13:09.810 --> 13:17.400 And now we will clear the register which is returning the value and we will call the print F. 13:17.670 --> 13:18.410 So that's it. 13:18.420 --> 13:22.140 Now we will write our division divide. 13:22.230 --> 13:25.920 Now we will call the move. 13:28.870 --> 13:29.740 Number one. 13:29.740 --> 13:34.960 Here we are loading the value of number one to racks. 13:34.960 --> 13:37.330 And now we will call the. 13:40.670 --> 13:50.120 MOV rdx zero clearing the rdx register, which is a reminder and i div here. 13:51.410 --> 13:52.340 He was. 13:53.360 --> 13:54.050 And. 13:55.760 --> 13:56.660 Award. 13:57.940 --> 13:59.350 Number two. 14:04.630 --> 14:13.090 And after that, with this here we are telling the assembler assembly to divide the racks by the value 14:13.090 --> 14:17.740 of number two, which is a 64 bit, uh, division. 14:17.740 --> 14:23.650 And this is the equation in racks reminder in RDX. 14:23.650 --> 14:26.140 And we will use the move here. 14:28.560 --> 14:29.340 Move. 14:29.370 --> 14:30.510 Result. 14:31.440 --> 14:32.220 Result. 14:32.250 --> 14:42.150 I Rex, this is the this is for storing the quotient quotient of in result I and now we will also modulo 14:42.480 --> 14:43.830 modulo here. 14:43.830 --> 14:49.710 This is for storing the reminder or restoring the reminder in modulo. 14:49.710 --> 14:51.300 Here are the x. 14:51.300 --> 14:54.540 Now we will need to display the quotient quotient. 14:54.750 --> 15:06.420 So display the quotient and now we will need to load the address of format string to move the the i 15:06.540 --> 15:10.590 fmt int mov rsi TV. 15:10.590 --> 15:15.750 This is for loading the address of message to RSI and move the. 15:18.800 --> 15:19.490 Now we are. 15:21.130 --> 15:23.770 RSI side, the X here. 15:24.010 --> 15:28.580 The result here is not the value of result to RDX. 15:28.750 --> 15:31.660 Now move the rax zero. 15:31.660 --> 15:34.450 Clear the rax register and call the. 15:35.620 --> 15:36.470 Printf. 15:37.480 --> 15:39.880 And now we need to display the reminder. 15:40.000 --> 15:42.790 And that's all display. 15:44.920 --> 15:46.150 Display the. 15:47.270 --> 15:48.410 Reminder. 15:48.620 --> 15:51.710 And here we will do the same logic here. 15:51.740 --> 15:57.260 Move by Fmt and move. 15:57.940 --> 16:03.550 RSI REM and mov rdx modulo. 16:06.410 --> 16:09.600 And after that, we will move the racks. 16:09.650 --> 16:10.340 Zero. 16:10.610 --> 16:13.480 And after that, we will call the print f. 16:14.970 --> 16:16.590 To display the formatted message. 16:16.590 --> 16:19.270 And now we need to write three instructions as well. 16:19.290 --> 16:25.050 Move rsp rbp for restoring the stack pointer. 16:25.080 --> 16:26.220 Pop Rbp. 16:28.140 --> 16:33.900 For restoring the bass pointer and we will return from the, uh, main function.