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digitalmars.D.learn - [DTrace probe] is there a [portable] way to add section to elf

reply drug <drug2004 bk.ru> writes:
I'd like to add (and modify) section to ELF executable to implement 
DTrace probes. DTrace does it in probe assembly:
```
__asm__ __volatile__ (
	"990: nop
	.pushsection .note.stapsdt,\"?\",\"note\"
	.balign 4
	.4byte 992f-991f, 994f-993f, 3
	991: .asciz \"stapsdt\"
	992: .balign 4
	993: .8byte 990b
	.8byte _.stapsdt.base
	.8byte 0
	.asciz \"myapp\"
	.asciz \"func_call\"
	.asciz \"%n[_SDT_S1] %[_SDT_A1] %n[_SDT_S2] %[_SDT_A2]\"
	994: .balign 4
	.popsection"
	:: [_SDT_S1] "n" (SNIPPED_ONE),
	   [_SDT_A1] "nor" ((a)),
	   [_SDT_S2] "n" (SNIPPED_TWO),
	   [_SDT_A2] "nor" ((b))
);
```

So I need a way to add no op operation and define some data in 
`.note.stapsdt` section. This page https://dlang.org/spec/iasm.html does 
not contain any information about sections
Oct 23 2019
parent welkam <wwwelkam gmail.com> writes:
On Wednesday, 23 October 2019 at 15:24:13 UTC, drug wrote:

 I'd like to add (and modify) section to ELF executable to 
 implement DTrace probes. DTrace does it in probe assembly:
 ```
 __asm__ __volatile__ (
 	"990: nop
 	.pushsection .note.stapsdt,\"?\",\"note\"
 	.balign 4
 	.4byte 992f-991f, 994f-993f, 3
 	991: .asciz \"stapsdt\"
 	992: .balign 4
 	993: .8byte 990b
 	.8byte _.stapsdt.base
 	.8byte 0
 	.asciz \"myapp\"
 	.asciz \"func_call\"
 	.asciz \"%n[_SDT_S1] %[_SDT_A1] %n[_SDT_S2] %[_SDT_A2]\"
 	994: .balign 4
 	.popsection"
 	:: [_SDT_S1] "n" (SNIPPED_ONE),
 	   [_SDT_A1] "nor" ((a)),
 	   [_SDT_S2] "n" (SNIPPED_TWO),
 	   [_SDT_A2] "nor" ((b))
 );
 ```

 So I need a way to add no op operation and define some data in 
 `.note.stapsdt` section. This page 
 https://dlang.org/spec/iasm.html does not contain any 
 information about sections


I hope you are not mixing up D SCRIPTING language that is used by 
Dtrace and D PROGRAMMING language.

Second thing is that ELF format is used by Linux and other 
operating systems use different executable formats (mach-0 for 
macOs and PE for windows). So by definition its not portable.

D's inline asm does not provide a way to modify *.obj files. It 
just insert your asm at that place.
Oct 24 2019