Import SQLite 3.10.2.

third_party/sqlite/src/tool/vdbe_profile.tcl

 #!/bin/tclsh
 #
+# SUMMARY:
 # Run this script in the same directory as the "vdbe_profile.out" file.
 # This script summarizes the results contained in that file.
 #
+# DETAILS:
+# Compile SQLite using the -DVDBE_PROFILE option on Linux.  This causes 
+# performance information about individual VDBE operations to be appended
+# to the "vdbe_profile.out" file.  After content has been accumulated in
+# vdbe_profile.out, run this script to analyze the output and generate a
+# report.
+#
 if {![file readable vdbe_profile.out]} {
   error "run this script in the same directory as the vdbe_profile.out file"
 }
 set in [open vdbe_profile.out r]
 set stmt {}
 set allstmt {}
 while {![eof $in]} {
   set line [gets $in]
   if {$line==""} continue
   if {[regexp {^---- } $line]} {
@@ skipping 57 matching lines @@
 foreach op [lsort [array names opcnt]] {
   set cx $opcnt($op)
   set tx $opcycle($op)
   if {$cx==0} {
     set ax 0
   } else {
     set ax [expr {$tx/$cx}]
   }
   puts [format {%8d %12d %12d %s} $cx $tx $ax $op]
 }