x86-64 instructions are designed so that commonly used instructions and those with fewer operands are encoded in a smaller number of bytes. Instructions range in length from 1 to 15 bytes.
x86-64 assembly comes in two flavors: ATT and Intel. ATT is most common in Linux systems so I focus on that. The most important distinction between the two is operand ordering: Intel syntax lists multiple operands in reverse order compared to ATT.
%%ANKI
Basic
x86-64 assembly comes in what two formats?
Back: ATT and Intel.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1710959313804-->
END%%
%%ANKI
Basic
Which x86-64 assembly format does Linux use?
Back: ATT.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1710959313810-->
END%%
%%ANKI
Basic
Which x86-64 assembly format does Microsoft use?
Back: Intel.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1710959313814-->
END%%
%%ANKI
Basic
What is the "most confusing" difference between ATT and Intel assembly?
Back: Multiple operands in one are listed in reverse order relative to the other.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1710959313818-->
END%%
%%ANKI
Basic
What term describes assembly lines with a leading `.`?
Back: Directives.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1710959313822-->
END%%
%%ANKI
Basic
Assembly directives are important for what two programs?
Back: The assembler and the linker.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
How many general-purpose registers are available to x86-64 instructions?
Back: 16
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889856-->
END%%
%%ANKI
Cloze
The x86 64-bit registers all start with prefix {`%r`}.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889861-->
END%%
%%ANKI
Cloze
The x86 32-bit registers all start with prefix {`%e`}.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889864-->
END%%
%%ANKI
Basic
Instructions that generate 1-byte quantities do what to the remaining bytes of a register?
Back: Leaves them alone.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889866-->
END%%
%%ANKI
Basic
Instructions that generate 2-byte quantities do what to the remaining bytes of a register?
Back: Leaves them alone.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889869-->
END%%
%%ANKI
Basic
Instructions that generate 4-byte quantities do what to the remaining bytes of a register?
Back: Zeroes them out.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889872-->
END%%
%%ANKI
Basic
Instructions that generate 8-byte quantities do what to the remaining bytes of a register?
Back: N/A
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889874-->
END%%
There are three types of operands:
* **Immediates**. These denote constant values. In ATT assembly, they are written with a `$` followed by an integer using standard C notation.
* **Registers**. These denote the contents of a register.
* **Memory**. These denote some memory location according to a computed address (i.e. the **effective address**).
What are the three types of operands instructions can act on?
Back: Immediates, registers, and memory addresses.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889877-->
END%%
%%ANKI
Basic
What are the types of source operands instructions can specify?
Back: Immediates, registers, and memory addresses.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889887-->
END%%
%%ANKI
Basic
What are the types of destination operands instructions can specify?
Back: Registers and memory addresses.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889894-->
END%%
%%ANKI
Basic
What does an immediate operand denote?
Back: A constant value.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889909-->
END%%
%%ANKI
Basic
What is the operand value of form $r_a$?
Back: $R[r_a]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889912-->
END%%
%%ANKI
Basic
What is the operand value of form $Imm$?
Back: $M[Imm]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889916-->
END%%
%%ANKI
Basic
What is the operand value of form $(r_a)$?
Back: $M[R[r_a]]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889920-->
END%%
%%ANKI
Basic
What is the operand value of form $Imm(r_b)$?
Back: $M[Imm + R[r_b]]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889923-->
END%%
%%ANKI
Basic
What is the operand value of form $(r_b, r_i)$?
Back: $M[R[r_b] + R[r_i]]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889927-->
END%%
%%ANKI
Basic
What is the operand value of form $Imm(r_b, r_i)$?
Back: $M[Imm + R[r_b] + R[r_i]]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889930-->
END%%
%%ANKI
Basic
What is the operand value of form $(,r_i,s)$?
Back: $M[R[r_i] \cdot s]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889933-->
END%%
%%ANKI
Basic
What is the operand value of form $Imm(,r_i,s)$?
Back: $M[Imm + R[r_i] \cdot s]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889937-->
END%%
%%ANKI
Basic
What is the operand value of form $(r_b,r_i,s)$?
Back: $M[R[r_b] + R[r_i] \cdot s]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889941-->
END%%
%%ANKI
Basic
What is the operand value of form $Imm(r_b,r_i,s)$?
Back: $M[Imm + R[r_b] + R[r_i] \cdot s]$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889945-->
END%%
%%ANKI
Basic
What distinguishes operand value $r_a$ from $(r_a)$?
Back: The former denotes the register value. The latter denotes the value in memory at the address stored in $r_a$.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713212889949-->
END%%
%%ANKI
Basic
What values can $s$ take on in operand form $Imm(r_b,r_i,s)$?
Back: $1$, $2$, $4$, or $8$.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713213168875-->
END%%
%%ANKI
Basic
What operand form is named "register"?
Back: $r_a$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713213168878-->
END%%
%%ANKI
Basic
What operand form is named "absolute"?
Back: $Imm$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713213168881-->
END%%
%%ANKI
Basic
What operand form is named "indirect"?
Back: $(r_a)$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713213168884-->
END%%
%%ANKI
Basic
What operand form is named "base + displacement"?
Back: $Imm(r_b)$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713213168887-->
END%%
%%ANKI
Basic
What is the most general operand form named "indexed" (*not* "scaled indexed")?
Back: $Imm(r_b, r_i)$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713213168890-->
END%%
%%ANKI
Basic
What is the most general operand form named "scaled indexed" (*not* indexed)?
Back: $Imm(r_b, r_i, s)$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
The MOV instruction class has four primary variants: `movb`, `movw`, `movl`, and `movq`. There also exist zero extension and sign extension variations in the forms of MOVS and MOVZ.
Notice there is no `movzlq` instruction. `movl` covers this functionality since, by convention, instructions moving double words into a 64-bit register automatically zeroes out the upper 32 bits.
What four variants does `MOV` instructions take on in x86-64?
Back: `movb`, `movw`, `movl`, `movq`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933397-->
END%%
%%ANKI
Basic
How many bytes does a `movb` instruction operate on?
Back: One.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933403-->
END%%
%%ANKI
Basic
How many bytes does a `movw` instruction operate on?
Back: Two.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933406-->
END%%
%%ANKI
Basic
How many bytes does a `movl` instruction operate on?
Back: Four.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933409-->
END%%
%%ANKI
Basic
How many bytes does a `movq` instruction operate on?
Back: Eight.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933413-->
END%%
%%ANKI
Basic
What combination of source and destination types is prohibited in `MOV` instructions?
Back: A source and destination memory address.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933416-->
END%%
%%ANKI
Basic
What is the result of `%rax` after instruction `movl $0x4050,%eax`?
Back: Upper 32-bits is `0` and lower 32-bits is `0x4050`.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933419-->
END%%
%%ANKI
Basic
What is the result of `%rax` after instruction `movq $0x4050,%rax`?
Back: The 64-bit value is `0x4050`.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933423-->
END%%
%%ANKI
Basic
What is the result of `%rax` after instruction `movw $0x4050,%ax`?
Back: The upper 48 bits are unchanged and the lower 16 bits are `0x4050`.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933426-->
END%%
%%ANKI
Basic
What is the result of `%rax` after instruction `movb $0x4050,%al`?
Back: The upper 56 bits are unchanged and the lower 8 bits are `0x50`.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933430-->
END%%
%%ANKI
Basic
What is the result of `%rax` after instruction `movw $0x4050,%al`?
Back: N/A. Invalid operand for instruction.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933433-->
END%%
%%ANKI
Basic
What caveat is applied to the source operand of `movq`?
Back: Immediates are 32-bit two's-complement numbers sign extended to 64-bits.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933437-->
END%%
%%ANKI
Basic
What `mov` instruction is needed when working with 64-bit immediate sources?
Back: `movabsq`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933441-->
END%%
%%ANKI
Basic
What purpose does `movabsq` solve that `movq` does not?
Back: `movabsq` can have an arbitrary 64-bit immediate source.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933448-->
END%%
%%ANKI
Basic
What is the result of `%rax` after the following instructions?
```asm
movabsq $0x0011223344556677, %rax
movb $-1, %al
```
Back: `0x00112233445566FF`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933452-->
END%%
%%ANKI
Basic
What is the result of `%rax` after the following instructions?
```asm
movabsq $0x0011223344556677, %rax
movw $-1, %ax
```
Back: `0x001122334455FFFF`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933455-->
END%%
%%ANKI
Basic
What is the result of `%rax` after the following instructions?
```asm
movabsq $0x0011223344556677, %rax
movl $-1, %eax
```
Back: `0x00000000FFFFFFFF`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933458-->
END%%
%%ANKI
Basic
What is the result of `%rax` after the following instructions?
```asm
movabsq $0x0011223344556677, %rax
movq $-1, %rax
```
Back: `0xFFFFFFFFFFFFFFFF`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933461-->
END%%
%%ANKI
Basic
What is the `MOVZ` instruction class?
Back: `MOV` instructions that zero extend the source to fit into the destination.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933464-->
END%%
%%ANKI
Basic
What is the `MOVS` instruction class?
Back: `MOV` instructions that sign extend the source to fit into the destination.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933466-->
END%%
%%ANKI
Basic
What does the `movzbw` instruction do?
Back: Moves a zero-extended byte to a word.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933469-->
END%%
%%ANKI
Basic
What does the `movslq` instruction do?
Back: Moves a sign-extended double word to a quad word.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933472-->
END%%
%%ANKI
Basic
What does the `movslb` instruction do?
Back: N/A. This instruction does not exist.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933475-->
END%%
%%ANKI
Basic
What combinatorial argument explains the number of `MOVS` instructions?
Back: There exists an instruction for each smaller declaration to larger declaration.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933478-->
END%%
%%ANKI
Basic
What `MOVZ` instruction is "missing"?
Back: `movzlq`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933483-->
END%%
%%ANKI
Basic
What is the result of `%rax` after the following instructions?
```asm
movabsq $0x0011223344556677, %rax
movb $0xAA, %dl
movb %dl,%al
```
Back: `0x00112233445566AA`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933486-->
END%%
%%ANKI
Basic
What is the result of `%rax` after the following instructions?
```asm
movabsq $0x0011223344556677, %rax
movb $0xAA, %dl
movsbq %dl,%rax
```
Back: `0xFFFFFFFFFFFFFFAA`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1713625933489-->
END%%
%%ANKI
Basic
What is the result of `%rax` after the following instructions?
```asm
movabsq $0x0011223344556677, %rax
movb $0xAA, %dl
movzbq %dl,%rax
```
Back: `0x00000000000000AA`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
Tags: c17
<!--ID: 1714677608754-->
END%%
%%ANKI
Basic
Dereferencing a pointer in C equates to what two operations in x86?
Back: Copying the pointer into a register and then using the register in a memory reference.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
| `pushq` | S | R[%rsp] <-R[%rsp]-8<br/>M[R[%rsp]] <-S|Pushquadword|
| `popq` | D | D <-M[R[%rsp]]<br/>R[%rsp] <-R[%rsp]+8|Popquadword|
In x86 processors, the stack grows downward, with the "top" of the stack corresponding to lower addresses.
%%ANKI
Basic
In what direction do x86-64 stacks grow?
Back: Downward.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284944-->
END%%
%%ANKI
Cloze
The x86-64 stack grows such that the top element has the {lowest} address of all stack elements.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284947-->
END%%
%%ANKI
Basic
What instruction is used to push elements onto the stack?
Back: `pushq`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284951-->
END%%
%%ANKI
Basic
What instruction is used to pop elements off of the stack?
Back: `popq`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284955-->
END%%
%%ANKI
Basic
How is `pushq %rbp` equivalently written using a pair of instructions?
Back:
```asm
subq 8,%rsp
movq %rbp,(%rsp)
```
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284959-->
END%%
%%ANKI
Basic
How is `popq %rax` equivalently written using a pair of instructions?
Back:
```asm
movq (%rsp),%rax
addq 8,%rsp
```
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284962-->
END%%
%%ANKI
Cloze
{1:`pushq`} is to {2:`subq`} as {2:`popq`} is to {1:`addq`}.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284966-->
END%%
%%ANKI
Basic
If `%rsp` has value `0x108`, what value does it have after a `pushq` instruction?
Back: `0x100`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284971-->
END%%
%%ANKI
Basic
If `%rsp` has value `0x108`, what value does it have after a `popq` instruction?
Back: `0x110`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284975-->
END%%
%%ANKI
Basic
Which register contains a pointer to the top of the stack?
Back: `%rsp`
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1715377284980-->
END%%
%%ANKI
Basic
What is the `%rsp` register typically used for?
Back: The stack pointer.
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
* Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
