ARM function declaring macro
Thanks for reading first.
I'm trying to understand some code from OPTEE-OS.
This a part of macro and seems trying to declaring a function.
.macro LOCAL_FUNC name colon
.section .text.name
.func name
.type name , %function
name colon
.endm
This function would be located in .text section.
And my question is What is the purpose of below code?
name colon
And also in below code,
.macro END_FUNC name
.size name , .-name
.endfunc
.endm
Why the .size should be written there?
Thanks for answering previously.
macros
edited Nov 19 '18 at 4:19
old_timer
48.7k761124
asked Nov 18 '18 at 22:42
Jeungwoo YooJeungwoo Yoo
3391515
add a comment |
Thanks for reading first.
I'm trying to understand some code from OPTEE-OS.
This a part of macro and seems trying to declaring a function.
.macro LOCAL_FUNC name colon
.section .text.name
.func name
.type name , %function
name colon
.endm
This function would be located in .text section.
And my question is What is the purpose of below code?
name colon
And also in below code,
.macro END_FUNC name
.size name , .-name
.endfunc
.endm
Why the .size should be written there?
Thanks for answering previously.
macros
edited Nov 19 '18 at 4:19
old_timer
48.7k761124
asked Nov 18 '18 at 22:42
Jeungwoo YooJeungwoo Yoo
3391515
add a comment |
Thanks for reading first.
I'm trying to understand some code from OPTEE-OS.
This a part of macro and seems trying to declaring a function.
.macro LOCAL_FUNC name colon
.section .text.name
.func name
.type name , %function
name colon
.endm
This function would be located in .text section.
And my question is What is the purpose of below code?
name colon
And also in below code,
.macro END_FUNC name
.size name , .-name
.endfunc
.endm
Why the .size should be written there?
Thanks for answering previously.
macros
edited Nov 19 '18 at 4:19
old_timer
48.7k761124
asked Nov 18 '18 at 22:42
Jeungwoo YooJeungwoo Yoo
3391515
Thanks for reading first.
I'm trying to understand some code from OPTEE-OS.
This a part of macro and seems trying to declaring a function.
.macro LOCAL_FUNC name colon
.section .text.name
.func name
.type name , %function
name colon
.endm
This function would be located in .text section.
And my question is What is the purpose of below code?
name colon
And also in below code,
.macro END_FUNC name
.size name , .-name
.endfunc
.endm
Why the .size should be written there?
Thanks for answering previously.
macros
macros
edited Nov 19 '18 at 4:19
old_timer
48.7k761124
asked Nov 18 '18 at 22:42
Jeungwoo YooJeungwoo Yoo
3391515
edited Nov 19 '18 at 4:19
old_timer
48.7k761124
asked Nov 18 '18 at 22:42
Jeungwoo YooJeungwoo Yoo
3391515
edited Nov 19 '18 at 4:19
old_timer
48.7k761124
edited Nov 19 '18 at 4:19
old_timer
48.7k761124
edited Nov 19 '18 at 4:19
old_timer
48.7k761124
48.7k761124
asked Nov 18 '18 at 22:42
Jeungwoo YooJeungwoo Yoo
3391515
asked Nov 18 '18 at 22:42
Jeungwoo YooJeungwoo Yoo
3391515
asked Nov 18 '18 at 22:42
Jeungwoo YooJeungwoo Yoo
3391515
3391515
add a comment |
add a comment |
1 Answer
1
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oldest
votes
The name colon will create a label with the given name, because labels in ARM assembly language are given by a string followed by a colon. This will allow code following an expansion of the LOCAL_FUNC macro to be called by branching to a label of the same name.
The size directive calculates the amount of space that is being used by the thing that a symbol points to, which means that the linker can then exclude that symbol entirely if it is unused. See this blog post for more on size.
answered Nov 19 '18 at 12:25
cooperisedcooperised
1,359813
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
The name colon will create a label with the given name, because labels in ARM assembly language are given by a string followed by a colon. This will allow code following an expansion of the LOCAL_FUNC macro to be called by branching to a label of the same name.
The size directive calculates the amount of space that is being used by the thing that a symbol points to, which means that the linker can then exclude that symbol entirely if it is unused. See this blog post for more on size.
answered Nov 19 '18 at 12:25
cooperisedcooperised
1,359813
add a comment |
The name colon will create a label with the given name, because labels in ARM assembly language are given by a string followed by a colon. This will allow code following an expansion of the LOCAL_FUNC macro to be called by branching to a label of the same name.
The size directive calculates the amount of space that is being used by the thing that a symbol points to, which means that the linker can then exclude that symbol entirely if it is unused. See this blog post for more on size.
answered Nov 19 '18 at 12:25
cooperisedcooperised
1,359813
add a comment |
The name colon will create a label with the given name, because labels in ARM assembly language are given by a string followed by a colon. This will allow code following an expansion of the LOCAL_FUNC macro to be called by branching to a label of the same name.
The size directive calculates the amount of space that is being used by the thing that a symbol points to, which means that the linker can then exclude that symbol entirely if it is unused. See this blog post for more on size.
answered Nov 19 '18 at 12:25
cooperisedcooperised
1,359813
The name colon will create a label with the given name, because labels in ARM assembly language are given by a string followed by a colon. This will allow code following an expansion of the LOCAL_FUNC macro to be called by branching to a label of the same name.
The size directive calculates the amount of space that is being used by the thing that a symbol points to, which means that the linker can then exclude that symbol entirely if it is unused. See this blog post for more on size.
answered Nov 19 '18 at 12:25
cooperisedcooperised
1,359813
answered Nov 19 '18 at 12:25
cooperisedcooperised
1,359813
answered Nov 19 '18 at 12:25
cooperisedcooperised
1,359813
answered Nov 19 '18 at 12:25
cooperisedcooperised
1,359813
1,359813
add a comment |
add a comment |
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