A Perl script to generate an HTML definition list containing the LLVM
library dependencies, for documentation purposes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19194 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/GenLibDeps.pl b/utils/GenLibDeps.pl
new file mode 100755
index 0000000..3bdb92a
--- /dev/null
+++ b/utils/GenLibDeps.pl
@@ -0,0 +1,101 @@
+#!/usr/bin/perl -w
+#
+# Program:  GenLibDeps.pl
+#
+# Synopsis: Generate HTML output that shows the dependencies between a set of
+#           libraries. The output of this script should periodically replace 
+#           the similar content in the UsingLibraries.html document.
+#
+# Syntax:   GenLibDeps.pl <directory_with_libraries_in_it>
+#
+
+# Give first option a name.
+my $Directory = $ARGV[0];
+
+# Open the directory and read its contents, sorting by name and differentiating
+# by whether its a library (.a) or an object file (.o)
+opendir DIR,$Directory;
+my @files = readdir DIR;
+closedir DIR;
+@libs = grep(/libLLVM.*\.a$/,sort(@files));
+@objs = grep(/LLVM.*\.o$/,sort(@files));
+
+# Declare the hashes we will use to keep track of the library and object file
+# symbol definitions.
+my %libdefs;
+my %objdefs;
+
+# Gather definitions from the libraries
+foreach $lib (@libs ) {
+  open DEFS, 
+    "nm -g --defined-only $lib | grep ' [ABCDGRSTVW] ' | sed -e 's/^[0-9A-Fa-f]* [ABCDGRSTVW] //' | sort | uniq |";
+  while (<DEFS>) {
+    chomp($_);
+    $libdefs{$_} = $lib;
+  }
+  close DEFS;
+}
+
+# Gather definitions from the object files.
+foreach $obj (@objs ) {
+  open DEFS, 
+    "nm -g --defined-only $obj | grep ' [ABCDGRST] ' | sed -e 's/^[0-9A-Fa-f]* [ABCDGRST] //' | sort | uniq |";
+  while (<DEFS>) {
+    chomp($_);
+    $objdefs{$_} = $obj;
+  }
+  close DEFS;
+}
+
+# Generate one entry in the <dl> list. This generates the <dt> and <dd> elements
+# for one library or object file. The <dt> provides the name of the library or
+# object. The <dd> provides a list of the libraries/objects it depends on.
+sub gen_one_entry {
+  my $lib = $_[0];
+  print "  <dt><b>$lib</b</dt><dd>\n";
+  open UNDEFS, 
+    "nm -u $lib | grep ' U ' | sed -e 's/         U //' | sort | uniq |";
+  open DEPENDS,
+    "| sort | uniq > GenLibDeps.out";
+  while (<UNDEFS>) {
+    chomp;
+    if (defined($libdefs{$_}) && $libdefs{$_} ne $lib) {
+      print DEPENDS "$libdefs{$_}\n";
+    } elsif (defined($objdefs{$_}) && $objdefs{$_} ne $lib) {
+      $libroot = $lib;
+      $libroot =~ s/lib(.*).a/$1/;
+      if ($objdefs{$_} ne "$libroot.o") {
+        print DEPENDS "$objdefs{$_}\n";
+      }
+    }
+  }
+  close UNDEFS;
+  close DEPENDS;
+  open DF, "<GenLibDeps.out";
+  while (<DF>) {
+    chomp;
+    print "    $_\n";
+  }
+  close DF;
+  print "  </dd>\n";
+}
+
+# Make sure we flush on write. This is slower but correct based on the way we
+# write I/O in gen_one_entry.
+$| = 1;
+
+# Print the definition list tag
+print "<dl>\n";
+
+# Print libraries first
+foreach $lib (@libs) {
+  gen_one_entry($lib);
+}
+
+# Print objects second
+foreach $obj (@objs) {
+  gen_one_entry($obj);
+}
+
+# Print end tag of definition list element
+print "</dl>\n";