Linux perf demangle D symbols

[Alex Burton]

On Wednesday, 26 February 2020 at 07:20:03 UTC, Arun 
Chandrasekaran wrote:
> Does anyone use Linux perf here, with D symbols demangled?
>
> I'm on Ubuntu 19.10, but I can't get perf to demangle the D 
> symbols.

This is my sh script for performance monitoring on debian buster 
using Brendan Greggs flamegraph:

sudo perf record -F 99 -a --call-graph dwarf -- sleep 10
#sudo perf record -F 99 --call-graph dwarf -p 31984
sudo perf script > tree.perf
~/dev/FlameGraph/stackcollapse-perf.pl tree.perf > tree.folded
~/dev/FlameGraph/flamegraph.pl tree.folded > tree_.svg
cat tree_.svg | ./dfilt > tree.svg
firefox tree.svg

This is the source code in dfilt:

import std.ascii : isAlphaNum;
import std.algorithm;
import std.range;
import std.conv : to;
import std.demangle : demangle;
import std.functional : pipe;
import std.stdio;



string translateSymbol(string s)
{
	if (s[0..2] == "_D")
	{
		auto result = demangle(s);
		writefln("%s => %s",s,result);
	}
	return s;
}

string translateGroup(U)(U group)
{
	if ((group[0]))
		return demangle(group[1].to!string);
	else
		return group[1].to!string;
}

auto translateLine(string l)
{
	return l.chunkBy!(a => isAlphaNum(a) || a == 
'_').map!translateGroup.joiner;
}

void main()
{
     auto result = stdin.byLineCopy
         .map!translateLine
         .joiner("\n").array;
		
	result.copy(stdout.lockingTextWriter);
}


Hope this helps