Programming/Assembly - Revision history

Brodriguez: Brodriguez moved page Assembly to Programming/Assembly

2020-10-25T17:27:08Z

Brodriguez moved page Assembly to Programming/Assembly

← Older revision

Revision as of 17:27, 25 October 2020

Brodriguez: Add and update instructions

2020-03-16T21:13:45Z

Add and update instructions

← Older revision		Revision as of 21:13, 16 March 2020
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	* '''jne <l>''' - Jump when not equal, based on condition of register status codes.		* '''jne <l>''' - Jump when not equal, based on condition of register status codes.
	* '''jz <l>''' - Jump when last result was 0, based on condition of register status codes.		* '''jz <l>''' - Jump when last result was 0, based on condition of register status codes.
	* '''jg <l>''' - Jump when greater than, based on condition of register status codes.		* '''jg <l>''' - Jump when greater than (interpreted as signed), based on condition of register status codes.
	* '''jge <l>''' - Jump when greater than or equal, based on condition of register status codes.		* '''ja <l>''' - Jump when greater than (interpreted as unsigned), based on condition of register status codes.
	* '''jl <l>''' - Jump when less than, based on condition of register status codes.		* '''jge <l>''' - Jump when greater than or equal (interpreted as signed), based on condition of register status codes.
	* '''~~jli~~ <l>''' - Jump when less than or equal, based on condition of register status codes.		* '''jae <l>''' - Jump when greater than or equal (interpreted as unsigned), based on condition of register status codes.
			* '''jl <l>''' - Jump when less than (interpreted as signed), based on condition of register status codes.
			* '''jb <l>''' - Jump when less than (interpreted as unsigned), based on condition of register status codes.
			* '''jle <l>''' - Jump when less than or equal (interpreted as signed), based on condition of register status codes.
			* '''jbe <l>''' - Jump when less than or equal (interpreted as unsigned), based on condition of register status codes.
	* '''call <l>''' - Pushes current code location onto stack, then jumps to location indicated by value.		* '''call <l>''' - Pushes current code location onto stack, then jumps to location indicated by value.
	* '''ret''' - Pops top code location from stack, then jumps to indicated location.		* '''ret''' - Pops top code location from stack, then jumps to indicated location.

Brodriguez: Add instructions

2020-03-16T20:05:52Z

Add instructions

← Older revision		Revision as of 20:05, 16 March 2020
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	* '''xor <rm> <rmc>''' - Performs logical binary XOR operation on values. Puts result in location of first value.		* '''xor <rm> <rmc>''' - Performs logical binary XOR operation on values. Puts result in location of first value.
	* '''not <rm>''' - Performs two's compliment negation on value.		* '''not <rm>''' - Performs two's compliment negation on value.
	* '''shl <rm> <c>''' - Shift left. Does this a number of times equal to the second value. Puts result in ~~locatiton~~ of first value.		* '''shl <rm> <c>''' - Shift left. Does this a number of times equal to the second value. Puts result in location of first value.
	* '''shr <rm> <c>''' - Shift right. Does this a number of times equal to the second value. Puts result in ~~locatiton~~ of first value.		* '''shr <rm> <c>''' - Shift right. Does this a number of times equal to the second value. Puts result in location of first value.
			* '''sal <rm> <c>''' - Shift left. Does this a number of times equal to the load immediate.
			* '''sar <rm> <c>''' - Shift right. Does this a number of times equal to the load immediate.

	=== Control Flow ===		=== Control Flow ===

Brodriguez: Add addressing section

2020-02-04T02:17:56Z

Add addressing section

← Older revision		Revision as of 02:17, 4 February 2020
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	* '''call <l>''' - Pushes current code location onto stack, then jumps to location indicated by value.		* '''call <l>''' - Pushes current code location onto stack, then jumps to location indicated by value.
	* '''ret''' - Pops top code location from stack, then jumps to indicated location.		* '''ret''' - Pops top code location from stack, then jumps to indicated location.

			== Memory Addressing ==
			The following describes general memory addressing syntax, such as used in '''AT&T''' assembly formatting.

			=== Simple Addressing ===
			The most basic form of addressing follows the format of <code>(r)</code> where '''r''' is a register that contains a memory address. Using this syntax will read the value located at the given memory address.<br>
			For example: <code>push (%rcx)</code> will go to the memory location indicated by '''rcx''' and push that value to the stack.

			=== Complex Addressing ===
			Starting from the simple addressing mode, we can add additional values to meet more complicated demands.

			The general addressing format is <code>D(Rb,Ri,S)</code>, where:
			* '''D''' - Displacement. This is a numerical value we add to the base register address, giving a new address.
			* '''Rb''' - Base register. This is the equivalent of the register used above, in the '''Simple Addressing''' format.
			* '''Ri''' - Index register. Acts as an index offset. Useful for dealing with things like arrays.
			* '''S''' - Scale. The size of each indicated index. If not specified, defaults to 1. Only values of 1, 2, 4, or 8 are valid.

			Note that these can all be optional.

			For example, if we only want an address from '''rax''' but plus a displacement of 16, we can use:
			<code>16(%rax)</code>

			If, for example, we want an address from '''rax''' to denote the start of an array. Each array element is 4 bits long, and we want the 100th element, then we can use index and scale:
			<code>(%rax, %rcx, 4)</code>
			Note that this assumes '''rcx''' has a value of 100.

Brodriguez: Correct formatting

2020-02-03T14:22:18Z

Correct formatting

← Older revision		Revision as of 14:22, 3 February 2020
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	* '''xor <rm> <rmc>''' - Performs logical binary XOR operation on values. Puts result in location of first value.		* '''xor <rm> <rmc>''' - Performs logical binary XOR operation on values. Puts result in location of first value.
	* '''not <rm>''' - Performs two's compliment negation on value.		* '''not <rm>''' - Performs two's compliment negation on value.
	* '''shl <rm> <c> - Shift left. Does this a number of times equal to the second value. Puts result in ~~locaiton~~ of first value.		* '''shl <rm> <c>''' - Shift left. Does this a number of times equal to the second value. Puts result in locatiton of first value.
	* '''shr <rm> <c> - Shift right. Does this a number of times equal to the second value. Puts result in ~~locaiton~~ of first value.		* '''shr <rm> <c>''' - Shift right. Does this a number of times equal to the second value. Puts result in locatiton of first value.

	=== Control Flow ===		=== Control Flow ===

Brodriguez: Correct typo

2020-02-03T14:21:50Z

Correct typo

← Older revision		Revision as of 14:21, 3 February 2020
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	\|}		\|}

	In-depth details of how assembly ~~rdataegister~~ and function calling should work:		In-depth details of how assembly register and function calling should work:
	https://www.cs.princeton.edu/courses/archive/spring11/cos217/lectures/15AssemblyFunctions.pdf		https://www.cs.princeton.edu/courses/archive/spring11/cos217/lectures/15AssemblyFunctions.pdf

Brodriguez: Create instruction section

2020-02-03T14:20:13Z

Create instruction section

@@ Line 324: / Line 324: @@
 |}
-In-depth details of how assembly register and function calling should work:
+In-depth details of how assembly rdataegister and function calling should work:
 https://www.cs.princeton.edu/courses/archive/spring11/cos217/lectures/15AssemblyFunctions.pdf
@@ Line 335: / Line 335: @@
 == Instructions ==
-* '''mov <a>, <b>''' - Copies data location from one to the other.
+For all of the below, letters indicate what kind of value is accepted for each argument. The letters correspond to the following:

Brodriguez: Reorder page content

2020-02-03T13:45:59Z

Reorder page content

@@ Line 1: / Line 1: @@
-== Instruction Sizes ==
+== Syntax Types ==
-In 64 bit assembly, some assembly instructions will have letters appended to the end of the instruction, indicating the size of data being referenced. The letters are the following:
+For 32 bit (x86) assembly, there are two main syntax types. '''AT&T''' is mostly used in Unix environments, while '''Intel''' is mostly used in MS-DOS and Windows.<br>
-* '''Byte''' ('''b''') - A one-byte (8 bit) value.
+The differences are as follows:
-* '''Word''' ('''w''') - A two-byte (16 bit) value.
+{| class="wikitable" style="text-align: center;"
-* '''DoubleWord''' ('''l''') - A four-byte (32 bit) value.
+|-
-* '''QuadWord''' ('''q''') - A eight-byte (64 bit) value.
 == Registers ==
@@ Line 307: / Line 327: @@
 https://www.cs.princeton.edu/courses/archive/spring11/cos217/lectures/15AssemblyFunctions.pdf
+== Instruction Sizes ==
-== Syntax Types ==
+In 64 bit assembly, some assembly instructions will have letters appended to the end of the instruction, indicating the size of data being referenced. The letters are the following:
-For 32 bit (x86) assembly, there are two main syntax types. '''AT&T''' is mostly used in Unix environments, while '''Intel''' is mostly used in MS-DOS and Windows.<br>
+* '''Byte''' ('''b''') - A one-byte (8 bit) value.
-The differences are as follows:
+* '''Word''' ('''w''') - A two-byte (16 bit) value.
-{| class="wikitable" style="text-align: center;"
+* '''DoubleWord''' ('''l''') - A four-byte (32 bit) value.
-|-
+* '''QuadWord''' ('''q''') - A eight-byte (64 bit) value.
 == Instructions ==
 * '''mov <a>, <b>''' - Copies data location from one to the other.

Brodriguez: Create AT&T vs Intel section

2020-02-03T13:45:04Z

Create AT&T vs Intel section

← Older revision		Revision as of 13:45, 3 February 2020
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	In-depth details of how assembly register and function calling should work:		In-depth details of how assembly register and function calling should work:
	https://www.cs.princeton.edu/courses/archive/spring11/cos217/lectures/15AssemblyFunctions.pdf		https://www.cs.princeton.edu/courses/archive/spring11/cos217/lectures/15AssemblyFunctions.pdf


			== Syntax Types ==
			For 32 bit (x86) assembly, there are two main syntax types. '''AT&T''' is mostly used in Unix environments, while '''Intel''' is mostly used in MS-DOS and Windows.<br>
			The differences are as follows:
			{\| class="wikitable" style="text-align: center;"
			\|-
			!
			! AT&T
			! Intel
			\|-
			! Signs
			\| Instructions need size definition suffix (see [[#Instruction Sizes]]).<br>Values need '''%''' prefix for registers, and '''$''' prefix for constants.<br>Ex:<code>%eax</code>
			\| Automatically detects size and type of value. Signs are not needed.<br>Ex:<code>eax</code>
			\|-
			! Value Order
			\| Source first, destination second.<br>Ex:<code>mov $5, %eax</code>
			\| Destination first, source second.<br>Ex:<code>mov eax, 5</code>
			\|-
			! Value Size
			\| Size suffix (see [[#Instruction Sizes]]) must be added to instruction.<br>Ex:<code>addl %eax, %ebx</code>
			\| Size automatically derived from register used. In instances where size is ambiguous, must use a size keyword ('''byte''', '''word''', '''dword''', '''qword''').<br>Ex:<code>add eax, ebx</code>
			\|-
			! Effective Address
			\| Uses general memory address syntax.<br>Ex:<code>(%ebx, %ecx, 4)</code>
			\| Uses arithmetic expressions in square brackets.<br>Ex:<code>[ebx + ecx*4]</code>
			\|-
			\|}

			== Instructions ==
			* '''mov <a>, <b>''' - Copies data location from one to the other.

Brodriguez: Formatting

2020-02-03T13:14:38Z

Formatting

← Older revision		Revision as of 13:14, 3 February 2020
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	* '''Byte''' ('''b''') - A one-byte (8 bit) value.		* '''Byte''' ('''b''') - A one-byte (8 bit) value.
	* '''Word''' ('''w''') - A two-byte (16 bit) value.		* '''Word''' ('''w''') - A two-byte (16 bit) value.
	* '''DoubleWord''' (l) - A four-byte (32 bit) value.		* '''DoubleWord''' ('''l''') - A four-byte (32 bit) value.
	* '''QuadWord''' (q) - A eight-byte (64 bit) value.		* '''QuadWord''' ('''q''') - A eight-byte (64 bit) value.

	== Registers ==		== Registers ==