On Sat, Apr 24, 2021 at 05:27:34PM +0530, Aditya Srivastava wrote:

On 23/4/21 6:51 pm, Matthew Wilcox wrote:

quoted

On Fri, Apr 23, 2021 at 12:48:39AM +0530, Aditya Srivastava wrote:

quoted

+my $pointer_function = qr{([^\(]*\(\*)\s*\)\s*\(([^\)]*)\)};

Is that a pointer-to-function?  Or as people who write C usually call it,
a function pointer?  Wouldn't it be better to call it $function_pointer?

Will do it.

quoted

quoted

@@ -1210,8 +1211,14 @@ sub dump_struct($$) {
     my $decl_type;
     my $members;
     my $type = qr{struct|union};
+    my $packed = qr{__packed};
+    my $aligned = qr{__aligned};
+    my $cacheline_aligned_in_smp = qr{____cacheline_aligned_in_smp};
+    my $cacheline_aligned = qr{____cacheline_aligned};

I don't think those four definitions actually simplify anything.

quoted

+    my $attribute = qr{__attribute__\s*\(\([a-z0-9,_\*\s\(\)]*\)\)}i;

... whereas this one definitely does.

quoted

-	$members =~ s/\s*__attribute__\s*\(\([a-z0-9,_\*\s\(\)]*\)\)/ /gi;
-	$members =~ s/\s*__aligned\s*\([^;]*\)/ /gos;
-	$members =~ s/\s*__packed\s*/ /gos;
+	$members =~ s/\s*$attribute/ /gi;
+	$members =~ s/\s*$aligned\s*\([^;]*\)/ /gos;

Maybe put the \s*\([^;]*\) into $aligned?  Then it becomes a useful
abstraction.

Actually, I had made these variables as they were repeated here and at
-    my $definition_body =
qr{\{(.*)\}(?:\s*(?:__packed|__aligned|____cacheline_aligned_in_smp|____cacheline_aligned|__attribute__\s*\(\([a-z0-9,_\s\(\)]*\)\)))*};
+    my $definition_body =
qr{\{(.*)\}(?:\s*(?:$packed|$aligned|$cacheline_aligned_in_smp|$cacheline_aligned|$attribute))*};

So, defining them at a place might help.

What do you think?

I don't think that seeing $packed is any easier to read than __packed.
Indeed, I think it's harder, because now I have to look up what $packed
is defined as.

Defining a variable, say

	$decorations = qr{__packed|__aligned|____cacheline_aligned_in_smp|____cacheline_aligned|__attribute__\s*\(\([a-z0-9,_\s\(\)]*\)\))}
	(i didn't count brackets to be sure i got that right)

would be helpful because then we could say:

	my $definition_body = qr{\{(.*)\}...$decorations...

and have a fighting chance of understanding what it means.

Now, this other place we use it, we do the =~ operation a number of times.
Is there a way to use the $decorations variable to do the same thing
with a single operation?