college/Fall-2024/CS-3843/Assignments/12/Assignment.typ

#import "@preview/codly:1.1.1": *
#import "@preview/codly-languages:0.1.1": *
#show: codly-init.with()

#codly(
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#show link: set text(blue)
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    radius: 4pt,
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#let solvein(solution) = {
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  box(
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    stroke: blue + .3pt,
    fill: rgb(0, 149, 255, 15%),
    radius: 4pt,
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}

#let note(content) = {
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#let notein(content) = {
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    stroke: luma(20%) + .3pt,
    fill: luma(95%),
    radius: 4pt,
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}

#align(center)[
  = CS 3843 Computer Organization
  HW 12\
  #underline[Price Hiller] *|* #underline[zfp106]
]
#line(length: 100%, stroke: .25pt)

#note[
  As a note I'm skipping the "cruft" inside the assembly output for this homework (stuff like the `.text`, `.file` directive, and whatnot). That's vaguely external to our actual code for use in the assembler, not a direct one-to-one translation of our code. I am focusing on the important bits.

  On some stuff, I may ignore some of the C code as the assembly generated doesn't cleanly match up at all. I've done my absolute best to keep things coherent, but I do want to apologize in advance if this proves hard to follow.
]

1. Please see below for the C version. You need to generate the assembly version of this C version.
  In your submission document, you need to include the screenshot of the assembly version. Then
  you need to write a discussion on the assembly version. Make sure to include what’s happening
  at each line of your assembly code, also you need to include how the control has been
  transferred from one place to another of your program

  #solve[
    #table(
      columns: 3,
      table.header([C code], [Assembly Code], [Description]),
      [
        ```c
        long absdiff_se(long x, long y) {
        ```
      ],
      [
        ```asm
        absdiff_se:
        ```
      ],
      [
        Create a label named ```asm absdiff_se```, the name of our C function.
      ],

      [
        ```c
        if (x < y) {
        ```
      ],
      [
        ```asm
        cmpq %rsi, %rdi
        jge .L2
        ```
      ],
      [
        Compare the two inputs of the function to each other and jump to the label `.L2` if ```c x >= y``` (by checking if the `SF` and `OF` flags are the same as a result of the ```asm cmpq``` instruction.)
      ],

      [
        ```c
        lt_cnt++;
        ```
      ],
      [
        ```asm
        movq	lt_cnt@GOTPCREL(%rip), %rdx
        movq (%rdx), %rax
        addq $1, %rax
        ```
      ],
      [
        1. Load the value for ```c lt_cnt``` from the global offset table into ```asm %rdx```.
        2. Load that derefenced value from ```asm %rdx``` into ```asm %rax```
        3. Finally, increment ```asm %rax``` by `1`, equivalent to ```c lt_cnt++```
      ],

      [
        ```c
        result = y - x;
        ```
      ],
      [
        ```asm
        movq %rax, (%rdx)
        movq %rsi, %rax
        subq %rdi, %rax
        ret
        ```
      ],
      [
        1. Copy the value of ```asm %rax``` into the value pointed to by ```asm (%rdx)```
        2. Copy the value of ```asm %rsi``` into ```asm %rax```
        3. Finally, subtract ```asm %rdi``` from ```asm %rax```, storing the result in ```asm %rax```
        4. Return control to the caller
      ],

      [
        ```c
        } else {
        ```
      ],
      [
        ```asm
        .L2:
        ```
      ],
      [
        If the earlier ```asm jge .L2``` found that the flags `SF` and `OF` were the same, we'll jump to this label/
      ],

      [
        ```c
        ge_cnt++;
        ```
      ],
      [
        ```asm
        movq	ge_cnt@GOTPCREL(%rip), %rdx
        movq	(%rdx), %rax
        addq	$1, %rax
        ```
      ],
      [
        1. Load the value for ```c ge_cnt``` from the global offset table into ```asm %rdx```.
        2. Load that derefenced value from ```asm %rdx``` into ```asm %rax```
        3. Finally, increment ```asm %rax``` by `1`, equivalent to ```c gt_cnt++```
      ],

      [
        ```c
        result = x - y;
        ```
      ],
      [
        ```asm
        movq %rax, (%rdx)
        movq %rdi, %rax
        subq %rsi, %rax
        ret
        ```
      ],
      [
        1. Copy the value of ```asm %rax``` into the value pointed to by ```asm (%rdx)```
        2. Copy the value of ```asm %rdi``` into ```asm %rax```
        3. Finally, subtract ```asm %rsi``` from ```asm %rax```, storing the result in ```asm %rax```
        4. Return control to the caller
      ],
    )
    #note[
      You may have noticed I skipped over the ```c return result;``` chunk of the C code. This is because that chunk is satisfied by the early `ret` calls in both branches of the assembly. Secondly, I skipped the `xorl` instructions as they're merely clearing the registers.
    ]
  ]
  #note[
    #table(
      columns: 2,
      table.header(
        [Original C Code],
        [Produced Assembly via ```sh gcc -Og -S```],
      ),

      [
        ```c
        long lt_cnt = 0;
        long ge_cnt = 0;
        long absdiff_se(long x, long y) {
          long result;
          if (x < y) {
            lt_cnt++;
            result = y - x;
          } else {
            ge_cnt++;
            result = x - y;
          }
          return result;
        }
        ```
      ],
      [
        ```asm
        	.file	"t.c"
        	.text
        	.globl	absdiff_se
        	.type	absdiff_se, @function
        absdiff_se:
        .LFB0:
        	.cfi_startproc
        	cmpq	%rsi, %rdi
        	jge	.L2
        	movq	lt_cnt@GOTPCREL(%rip), %rdx
        	movq	(%rdx), %rax
        	addq	$1, %rax
        	movq	%rax, (%rdx)
        	movq	%rsi, %rax
        	subq	%rdi, %rax
        	xorl	%edx, %edx
        	xorl	%esi, %esi
        	xorl	%edi, %edi
        	ret
        .L2:
        	movq	ge_cnt@GOTPCREL(%rip), %rdx
        	movq	(%rdx), %rax
        	addq	$1, %rax
        	movq	%rax, (%rdx)
        	movq	%rdi, %rax
        	subq	%rsi, %rax
        	xorl	%edx, %edx
        	xorl	%esi, %esi
        	xorl	%edi, %edi
        	ret
        	.cfi_endproc
        .LFE0:
        	.size	absdiff_se, .-absdiff_se
        	.globl	ge_cnt
        	.bss
        	.align 8
        	.type	ge_cnt, @object
        	.size	ge_cnt, 8
        ge_cnt:
        	.zero	8
        	.globl	lt_cnt
        	.align 8
        	.type	lt_cnt, @object
        	.size	lt_cnt, 8
        lt_cnt:
        	.zero	8
        	.ident	"GCC: (GNU) 13.3.0"
        	.section	.note.GNU-stack,"",@progbits
        ```
      ],
    )
  ]

2. Please see below for the C version. You need to generate the assembly version of this C version.
  In your submission document, you need to include the screenshot of the assembly version. Then
  you need to write a discussion on the assembly version. Make sure to include what’s happening
  at each line of your assembly code, also you need to include how the control has been
  transferred from one place to another of your program.
  #solve[
    #table(
      columns: 3,
      table.header([C code], [Assembly Code], [Description]),
      [
        ```c
        long absdiff(long x, long y) {
        ```
      ],
      [
        ```asm
        absdiff:
        ```
      ],
      [
        Create a label named ```asm absdiff```, the name of our C function.
      ],

      [
        ```c
        if (x < y) {
        ```
      ],
      [
        ```asm
        cmpq %rsi, %rdi
        jge .L2
        ```
      ],
      [
        Compare the two inputs of the function to each other and jump to the label `.L2` if ```c x >= y``` (by checking if the `SF` and `OF` flags are the same as a result of the ```asm cmpq``` instruction.)
      ],

      [
        ```c
        result = y - x;
        ```
      ],
      [
        ```asm
        movq %rsi, %rax
        subq %rsi, %rax
        ret
        ```
      ],
      [
        + Copy the value of ```asm %rsi``` into ```asm %rax```
        + Finally, subtract ```asm %rdi``` from ```asm %rax```, storing the result in ```asm %rax```
        + Return control to the caller
      ],

      [
        ```c
        else
        ```
      ],
      [
        ```asm
        .L2:
        ```
      ],
      [
        If the earlier ```asm jge .L2``` found that the flags `SF` and `OF` were the same, we'll jump to this label/
      ],

      [
        ```c
        result = x - y;
        ```
      ],
      [
        ```asm
        movq %rdi, %rax
        subq %rsi, %rax
        ret
        ```
      ],
      [
        1. Copy the value of ```asm %rax``` into the value pointed to by ```asm (%rdx)```
        2. Copy the value of ```asm %rdi``` into ```asm %rax```
        3. Finally, subtract ```asm %rsi``` from ```asm %rax```, storing the result in ```asm %rax```
        4. Return control to the caller
      ],
    )
  ]

  #note[
    #table(
      columns: 2,
      table.header(
        [Original C Code],
        [Produced Assembly via ```sh gcc -Og -S```],
      ),

      [
        ```c
        long absdiff(long x, long y) {
          long result;
          if (x < y)
            result = y - x;
          else
            result = x - y;
          return result;
        }
        ```
      ],
      [
        ```asm
        	.file	"t.c"
        	.text
        	.globl	absdiff
        	.type	absdiff, @function
        absdiff:
        .LFB0:
        	.cfi_startproc
        	cmpq	%rsi, %rdi
        	jge	.L2
        	movq	%rsi, %rax
        	subq	%rdi, %rax
        	xorl	%esi, %esi
        	xorl	%edi, %edi
        	ret
        .L2:
        	movq	%rdi, %rax
        	subq	%rsi, %rax
        	xorl	%esi, %esi
        	xorl	%edi, %edi
        	ret
        	.cfi_endproc
        .LFE0:
        	.size	absdiff, .-absdiff
        	.ident	"GCC: (GNU) 13.3.0"
        	.section	.note.GNU-stack,"",@progbits
        ```
      ],
    )
  ]


3. Please see below for the C version. You need to generate the assembly version of this C version.
  In your submission document, you need to include the screenshot of the assembly version. Then
  you need to write a discussion on the assembly version. Make sure to include what’s happening
  at each line of your assembly code, also you need to include how the control has been
  transferred from one place to another of your program.
  #solve[
    #table(
      columns: 3,
      table.header([C code], [Assembly Code], [Description]),
      [
        ```c
        long fact_do(long n) {
        ```
      ],
      [
        ```asm
        fact_do:
        ```
      ],
      [
        Create a label named ```asm fact_do```, the name of our C function.
      ],

      [
        ```c
        long result = 1;
        ```
      ],
      [
        ```asm
        movl $1, %eax
        ```
      ],
      [
        Assign ```c result``` to `1`, in assembly this means putting ```asm $1``` in the ```asm %eax``` register (the return register) as we will be returning this value after the function operation.
      ],

      [
        ```c
        do {
        ```
      ],
      [
        ```asm
        .L2:
        ```
      ],
      [
        Create a label named ```asm .L2:``` for control operations on the `do-while` loop.
      ],

      [
        ```c
        result *=n;
        ```
      ],
      [
        ```asm
        imulq %rdi, %rax
        ```
      ],
      [
        Multiply the input value by ```asm %rax``` and store the result of the multiplication in ```asm %rax```.
      ],

      [
        ```c
        n = n - 1;
        ```
      ],
      [
        ```asm
        subq $1, %rdi
        ```
      ],
      [
        Subtract `1` from our input value and store the result back in the input value's register, that being ```asm %rdi```.
      ],

      [
        ```c
        } while (n > 1);
        ```
      ],
      [
        ```asm
        cmpq $1, %rdi
        jg .L2
        ```
      ],
      [
        1. Run a comparison between the value ```asm $1``` and ```asm %rdi``` to set flags.
        2. If `~(SF^OF) & ~ZF`, then jump to the label ```asm .L2```. (Basically if the value stored in ```asm %rdi``` is more than `1`, jump to ```asm .L2```)
      ],

      [
        ```c
        return result;
        ```
      ],
      [
        ```asm
        ret
        ```
      ],
      [
        _Technically_ this isn't one to one. By setting our return value as `result` we've informed the compiler to insert values into ```asm %rax``` as that is our return register.
      ],
    )
  ]
  #note[
    #table(
      columns: 2,
      table.header(
        [Original C Code],
        [Produced Assembly via ```sh gcc -Og -S```],
      ),

      [
        ```c
        long fact_do(long n) {
          long result = 1;
          do {
            result *= n;
            n = n - 1;
          } while (n > 1);
          return result;
        }
        ```
      ],
      [
        ```asm
        	.file	"t.c"
        	.text
        	.globl	fact_do
        	.type	fact_do, @function
        fact_do:
        .LFB0:
        	.cfi_startproc
        	movl	$1, %eax
        .L2:
        	imulq	%rdi, %rax
        	subq	$1, %rdi
        	cmpq	$1, %rdi
        	jg	.L2
        	xorl	%edi, %edi
        	ret
        	.cfi_endproc
        .LFE0:
        	.size	fact_do, .-fact_do
        	.ident	"GCC: (GNU) 13.3.0"
        	.section	.note.GNU-stack,"",@progbits
        ```
      ],
    )
  ]

4. Please see below for the C version. You need to generate the assembly version of this C version.
  In your submission document, you need to include the screenshot of the assembly version. Then
  you need to write a discussion on the assembly version. Make sure to include what’s happening
  at each line of your assembly code, also you need to include how the control has been
  transferred from one place to another of your program.
  #solve[
    #table(
      columns: 3,
      table.header([C code], [Assembly Code], [Description]),
      [
        ```c
        long fact_while(long n) {
        ```
      ],
      [
        ```asm
        fact_while:
        ```
      ],
      [
        Create a label named ```asm fact_while```, the name of our C function.
      ],

      [
        ```c
        long result = 1;
        ```
      ],
      [
        ```asm
        movl $1, %eax
        ```
      ],
      [
        Assign ```c result``` to `1`, in assembly this means putting ```asm $1``` in the ```asm %eax``` register (the return register) as we will be returning this value after the function operation.
      ],

      [
        ```c
        while (/* omitted */)
        ```
      ],
      [
        ```asm
        .L3:
          ... ; omitted
        .L2:
          ... ; omitted
        ```
      ],
      [
        1. Create a label named ```asm .L3:``` for control operations on the `while` loop. This will allow access to the inner body of the loop.
        2. Create a separate label to handle the comparison (`n > 1`), named ```asm .L2:```, this will be jumped to unconditionally so the comparison can be validated
      ],

      [
        ```c
         (n > 1)
        ```
      ],
      [
        ```asm
        cmpq $1, %rdi
        jg .L3
        ```
      ],
      [
        1. Run a comparison between the value ```asm $1``` and ```asm %rdi``` to set flags.
        2. If `~(SF^OF) & ~ZF`, then jump to the label ```asm .L3```. (Basically if the value stored in ```asm %rdi``` is more than `1`, jump to ```asm .L3```)
      ],

      [
        ```c
        result *=n;
        ```
      ],
      [
        ```asm
        imulq %rdi, %rax
        ```
      ],
      [
        Multiply the input value by ```asm %rax``` and store the result of the multiplication in ```asm %rax```.
      ],

      [
        ```c
        n = n - 1;
        ```
      ],
      [
        ```asm
        subq $1, %rdi
        ```
      ],
      [
        Subtract `1` from our input value and store the result back in the input value's register, that being ```asm %rdi```.
      ],

      [
        ```c
        return result;
        ```
      ],
      [
        ```asm
        ret
        ```
      ],
      [
        _Technically_ this isn't one to one. By setting our return value as `result` we've informed the compiler to insert values into ```asm %rax``` as that is our return register.
      ],
    )
  ]
  #note[
    #table(
      columns: 2,
      table.header(
        [Original C Code],
        [Produced Assembly via ```sh gcc -Og -S```],
      ),

      [
        ```c
        long fact_while(long n) {
          long result = 1;
          while (n > 1) {
            result *= n;
            n = n - 1;
          }
          return result;
        }
        ```
      ],
      [
        ```asm
        	.file	"t.c"
        	.text
        	.globl	fact_while
        	.type	fact_while, @function
        fact_while:
        .LFB0:
        	.cfi_startproc
        	movl	$1, %eax
        	jmp	.L2
        .L3:
        	imulq	%rdi, %rax
        	subq	$1, %rdi
        .L2:
        	cmpq	$1, %rdi
        	jg	.L3
        	xorl	%edi, %edi
        	ret
        	.cfi_endproc
        .LFE0:
        	.size	fact_while, .-fact_while
        	.ident	"GCC: (GNU) 13.3.0"
        	.section	.note.GNU-stack,"",@progbits
        ```
      ],
    )
  ]

5. Please see below for the C version. You need to generate the assembly version of this C version.
  In your submission document, you need to include the screenshot of the assembly version. Then
  you need to write a discussion on the assembly version. Make sure to include what’s happening
  at each line of your assembly code, also you need to include how the control has been
  transferred from one place to another of your program.
  #note[
    Due to a lack of decent annotation tools on code in the core of Typst, the below description is kinda messy to follow. I do apologize for that, but I've done my best to ensure it's understandable.
  ]
  #solve[
    #table(
      columns: 3,
      table.header([C code], [Assembly Code], [Description]),
      [
        ```c
        long fact_for(long n) {
        ```
      ],
      [
        ```asm
        fact_for:
        ```
      ],
      [
        Create a label named ```asm fact_for```, the name of our C function.
      ],

      [
        ```c
        long result = 1;
        ```
      ],
      [
        ```asm
        movl $1, %edx
        ```
      ],
      [
        Assign ```c result``` to `1`, in assembly this means putting ```asm $1``` in the ```asm %edx``` register.
      ],

      [
        ```c
        for (i = 2; i <= n; i++)
        ```
      ],
      [
        ```asm
        jmp .L2
        .L3:
          ... ; omitted
          addq $1, %rax
        .L2:
          cmpq %rdi, %rax
          jle .L3
          ... ; omitted
        ```
      ],
      [
        + Create a label named ```asm .L3:``` for control operations on the `for` loop. This will allow access to the inner body of the loop.
        + Create a separate label to handle the comparison (`i <= 1`), named ```asm .L2:```, this will be jumped to unconditionally so the comparison can be validated
        + Run a comparison between the value ```asm $1``` and ```asm %rdi``` to set flags. (The `cmpq` instruction).
        + If `(SF^OF) | ZF`, then jump to the label ```asm .L3```. Basically if the value stored in ```asm %rdi``` is less than `2`, jump to ```asm .L3```. (The `jle .L3` instruction).
        + If we jump to the label `.L3`, we increment `%rax` (which stored `i`) by one, after executing the rest of the for loop body (see the next section).
      ],

      [
        ```c
        result *=n;
        ```
      ],
      [
        ```asm
        imulq %rax, %rdx
        ```
      ],
      [
        Multiply the input value by ```asm %rax``` and store the result of the multiplication in ```asm %rdx```.
      ],

      [
        ```c
        return result;
        ```
      ],
      [
        ```asm
        movq %rdx, %rax
        ret
        ```
      ],
      [
        Ensure where we've stored the result of our operations (in this case ```asm %rdx```) is put into a valid return register for use by the caller by copying ```asm %rdx``` to ```asm %rax```.
      ],
    )
  ]
  #note[
    #table(
      columns: 2,
      table.header(
        [Original C Code],
        [Produced Assembly via ```sh gcc -Og -S```],
      ),

      [
        ```c
        long fact_for(long n) {
          long i;
          long result = 1;
          for (i = 2; i <= n; i++)
            result *= i;
          return result;
        }
        ```
      ],
      [
        ```asm
        	.file	"t.c"
        	.text
        	.globl	fact_for
        	.type	fact_for, @function
        fact_for:
        .LFB0:
        	.cfi_startproc
        	movl	$1, %edx
        	movl	$2, %eax
        	jmp	.L2
        .L3:
        	imulq	%rax, %rdx
        	addq	$1, %rax
        .L2:
        	cmpq	%rdi, %rax
        	jle	.L3
        	movq	%rdx, %rax
        	xorl	%edx, %edx
        	xorl	%edi, %edi
        	ret
        	.cfi_endproc
        .LFE0:
        	.size	fact_for, .-fact_for
        	.ident	"GCC: (GNU) 13.3.0"
        	.section	.note.GNU-stack,"",@progbits
        ```
      ],
    )
  ]

6. Please see below for the C version. You need to generate the assembly version of this C version.
  In your submission document, you need to include the screenshot of the assembly version. Then
  you need to write a discussion on the assembly version. Make sure to include what’s happening
  at each line of your assembly code, also you need to include how the control has been
  transferred from one place to another of your program.
  #note[
    This is where it has gotten hilariously messy to even _try_ to track the matching C code for the given assembly output. As such, I've chosen to _not_ bother lining up C code and am instead going to go line by line on the assembly as I feel that may be a tiny bit easier to follow.
  ]
  #solve[
    #table(
      columns: 2,
      table.header([Assembly Code], [Description]),
      [
        ```asm
        switch_eg:
        ```
      ],
      [
        Define a label named ```asm switch_eg```.
      ],

      [
        ```asm
        subq $100, %rsi
        ```
      ],
      [
        Substract `100` from ```asm %rsi```, storing the result into ```asm %rsi```.
      ],

      [
        ```asm
        cmpq $6, %rsi
        ```
      ],
      [
        Compare the value `6` with the current value of ```asm %rsi```, setting the appropriate flags based on the comparison.
      ],

      [
        ```asm
        ja .L8
        ```
      ],
      [
        Jump to the label `.L8`, if the flags satisfy `~CF & ~ZF`.
      ],

      [
        ```asm
        leaq .L4(%rip), %rcx
        ```
      ],
      [
        Load the effective address from the global offset table into ```asm %rcx```
      ],

      [
        ```asm
        movslq	(%rcx,%rsi,4), %rax
        ```
      ],
      [
        Copy the value at `%rcx + 4 * %rsi` into ```asm %rax```, used to calculate offset for our switch statements.
      ],

      [
        ```asm
        addq %rcx, %rax
        ```
      ],
      [
        Add the value stored in ```asm %rcx``` into ```asm %rax```
      ],

      [
        ```asm
        jmp	*%rax
        ```
      ],
      [
        Do a indirect jump to load the address stored at ```asm %rax``` for our switch statements.
        _Begin to cry._
      ],

      [
        ```asm
        .L4:
        	.long	.L7-.L4
        	.long	.L8-.L4
        	.long	.L6-.L4
        	.long	.L5-.L4
        	.long	.L3-.L4
        	.long	.L8-.L4
        	.long	.L3-.L4
        	.text
        ```
      ],
      [
        Big ol' jump table.

      ],

      [
        ```asm
        .L7:
        	leaq	(%rdi,%rdi,2), %rax
        	leaq	(%rdi,%rax,4), %rdi
        	jmp	.L2
        ```
      ],
      [
        Loads data based on ```asm %rdi``` and ```asm %rax``` into ```asm %rax``` and ```asm %rdi``` respectively based on offsets. _Cry even more_.


        Then jump to the label ```asm .L2```
      ],

      [
        ```asm
        .L6:
          addq	$10, %rdi
        ```
      ],
      [
        Add `10` to ```asm %rdi```, this corresponds to our case `102`.
      ],

      [
        ```asm
        .L5:
        	addq	$11, %rdi
        ```
      ],
      [
        Add `11` to ```asm %rdi```, this corresponds to our case `103`.
      ],

      [
        ```asm
        .L2:
        	movq	%rdi, (%rdx)
            ... ; omitted
        	ret
        ```
      ],
      [
        Finally load our calculated value into the ```c *dest``` location via derefence. _Cry until we can't see._

        Finally, _finally_, return control back to the caller.
      ],

      [
        ```asm
        .L3:
        	imulq	%rdi, %rdi
        	jmp	.L2
        ```
      ],
      [
        This corresponds to cases `104` — `106`.
        + Multiply ```asm %rdi``` by itself, storing the result back in itself (```asm %rdi```).
        + Jump to the label ```asm .L2```.
      ],

      [
        ```asm
        .L8:
        	movl	$0, %edi
        	jmp	.L2
        ```
      ],
      [
        This corresponds to the default case.

        Copy the value `0` into ```asm %edi``` and jump to the label ```asm .L2```.
      ],
    )
  ]
  #note[Wow! That sucked.]
  #note[
    #table(
      columns: 2,
      table.header(
        [Original C Code],
        [Produced Assembly via ```sh gcc -Og -S```],
      ),

      [
        ```c
        void switch_eg(long x, long n, long *dest) {
          long val = x;
          switch (n) {
          case 100:
            val *= 13;
            break;
          case 102:
            val += 10;
          /* Fall through */
          case 103:
            val += 11;
            break;
          case 104:
          case 106:
            val *= val;
            break;
          default:
            val = 0;
          }
          *dest = val;
        }
        ```
      ],
      [
        ```asm
        	.file	"t.c"
        	.text
        	.globl	switch_eg
        	.type	switch_eg, @function
        switch_eg:
        .LFB0:
        	.cfi_startproc
        	subq	$100, %rsi
        	cmpq	$6, %rsi
        	ja	.L8
        	leaq	.L4(%rip), %rcx
        	movslq	(%rcx,%rsi,4), %rax
        	addq	%rcx, %rax
        	jmp	*%rax
        	.section	.rodata
        	.align 4
        	.align 4
        .L4:
        	.long	.L7-.L4
        	.long	.L8-.L4
        	.long	.L6-.L4
        	.long	.L5-.L4
        	.long	.L3-.L4
        	.long	.L8-.L4
        	.long	.L3-.L4
        	.text
        .L7:
        	leaq	(%rdi,%rdi,2), %rax
        	leaq	(%rdi,%rax,4), %rdi
        	jmp	.L2
        .L6:
        	addq	$10, %rdi
        .L5:
        	addq	$11, %rdi
        .L2:
        	movq	%rdi, (%rdx)
        	xorl	%eax, %eax
        	xorl	%edx, %edx
        	xorl	%ecx, %ecx
        	xorl	%esi, %esi
        	xorl	%edi, %edi
        	ret
        .L3:
        	imulq	%rdi, %rdi
        	jmp	.L2
        .L8:
        	movl	$0, %edi
        	jmp	.L2
        	.cfi_endproc
        .LFE0:
        	.size	switch_eg, .-switch_eg
        	.ident	"GCC: (GNU) 13.3.0"
        	.section	.note.GNU-stack,"",@progbits
        ```
      ],
    )
  ]