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digitalmars.D.ldc - ASan: disabling instrumentation of specific function

reply Johan Engelen <j j.nl> writes:
Hi all,
   I just implemented blacklisting of functions for the 
sanitizers' instrumentation via a blacklist file (this is what 
Clang also provides): 
https://github.com/ldc-developers/ldc/pull/2261

But I think it is nice if we also provide a way to disable 
sanitizer instrumentation by adding a UDA to a function. For PGO, 
back then, I choose to enable/disable profiling instrumentation 
through a pragma. However, adding our own pragmas is quite 
invasive and touches frontend code, whereas adding a UDA is easy 
and nicely compartmentalized.

Any ideas for a name of the UDA? And where to put it, in 
ldc.attributes?
Clang has the no_sanitize_address attribute.

Thanks,
   Johan
Aug 03 2017
parent reply Nicholas Wilson <iamthewilsonator hotmail.com> writes:
On Thursday, 3 August 2017 at 20:47:48 UTC, Johan Engelen wrote:

 Hi all,
   I just implemented blacklisting of functions for the 
 sanitizers' instrumentation via a blacklist file (this is what 
 Clang also provides): 
 https://github.com/ldc-developers/ldc/pull/2261

 But I think it is nice if we also provide a way to disable 
 sanitizer instrumentation by adding a UDA to a function. For 
 PGO, back then, I choose to enable/disable profiling 
 instrumentation through a pragma. However, adding our own 
 pragmas is quite invasive and touches frontend code, whereas 
 adding a UDA is easy and nicely compartmentalized.


Well, technically UDA's now touch fronted code, in the form of 
one entry in idgen.d.
I haven't implemented any pragmas, but I'm sure they will be more 
complex.


 Any ideas for a name of the UDA? And where to put it, in 
 ldc.attributes?
 Clang has the no_sanitize_address attribute.


Will blacklisting other sanitisers happen at a future point? if 
so it may make sense to do

// Probably already exists, but w/e
// force the type
enum Sanitizer : byte
{
     Address,
     Thread,
     // Other sanitisers
}
struct blacklist // or struct noSanitize
{
     Sanitizer s;
}

otherwise just

private struct _noSanitizeAddress {};
enum noSanitizeAddress = _noSanitizeAddress();


 Thanks,
   Johan
Aug 08 2017
parent Jacob Carlborg <doob me.com> writes:
On 2017-08-09 03:56, Nicholas Wilson wrote:


 Well, technically UDA's now touch fronted code, in the form of one entry
 in idgen.d.


idgen is basically a cache, nothing is _required_ to be in the cache. It 
also helps avoid misspelling symbol names known by the compiler.

-- 
/Jacob Carlborg
Aug 09 2017