From 0928896935411078a17e8dc45c9065c25fa14319 Mon Sep 17 00:00:00 2001
From: Mike Gerwitz <mike.gerwitz@ryansg.com>
Date: Fri, 13 Oct 2023 16:02:42 -0400
Subject: [PATCH] summary.xsl: Introduce maps for l:dep and preproc:symtable

This begins to chip away at the terrible performance of this system by using
maps where linear scans of the symbol table were otherwise taking place.

This does not yet touch `preproc:sym-deps`, which has the same problem.

Further, we may be able to get rid of symbol table maps per package by
utilizing `l:dep`; more to come.

This trims ~40s off of one of our larger programs (3m -> 2m20s), which is a
start, but there's still a ton of room for improvement.  I don't expect it
to be blazingly fast after all the optimization attempts---this has the same
problem as the XSLT-based linker did, which ended up being reimplemented in
Rust as TAMER---but it'll help to improve times in the meantime.

DEV-15153
---
 src/current/summary.xsl | 109 +++++++++++++++++++++++-----------------
 1 file changed, 63 insertions(+), 46 deletions(-)
diff --git a/src/current/summary.xsl b/src/current/summary.xsl
index 4410957a..9d98670d 100644
--- a/src/current/summary.xsl
+++ b/src/current/summary.xsl
@@ -27,6 +27,7 @@
   xmlns="http://www.w3.org/1999/xhtml"
   xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
+  xmlns:map="http://www.w3.org/2005/xpath-functions/map"
   xmlns:lv="http://www.lovullo.com/rater"
   xmlns:lvp="http://www.lovullo.com"
   xmlns:c="http://www.lovullo.com/calc"
@@ -64,6 +65,14 @@
 
 <xsl:variable name="program" select="/lv:package" />
 
+<xsl:variable name="program-symtable" as="element( l:dep )"
+              select="$program/l:dep" />
+<xsl:variable name="program-symtable-map"
+              as="map( xs:string, element( preproc:sym ) )"
+              select="map:merge(
+                        for $sym in $program-symtable/preproc:sym
+                          return map{ string( $sym/@name ) : $sym } )" />
+
 
 <!--
   Generate HTML page for a given rater/package
@@ -115,7 +124,7 @@
 
   <!-- intentional newline -->
   <xsl:text disable-output-escaping="yes">&lt;!DOCTYPE html&gt;
- </xsl:text>
+  </xsl:text>
 
   <html>
     <head>
@@ -144,30 +153,45 @@
       <xsl:variable name="pkg-self" select="
           document( concat( @__rootpath, @name, '.xmlo' ), . )/lv:*
         " />
-      <xsl:apply-templates
-        select="$pkg-self/lv:*" />
+
+      <xsl:variable name="symtable-self" as="element( preproc:symtable )"
+                    select="$pkg-self/preproc:symtable" />
+      <xsl:variable name="symtable-self-map" as="map( xs:string, element( preproc:sym ) )"
+                    select="map:merge(
+                              for $sym in $symtable-self/preproc:sym
+                                return map{ string( $sym/@name ) : $sym } )" />
+
+      <xsl:apply-templates select="$pkg-self/lv:*">
+        <xsl:with-param name="symtable-map" tunnel="yes"
+                        select="$symtable-self-map" />
+      </xsl:apply-templates>
 
       <!-- get a list of unique packages and typeset them -->
       <!-- TODO: this logic is duplicated; see gen-pkg-menu -->
-      <xsl:for-each select="
-          /lv:*/l:dep/preproc:sym[
-            @src
-            and not( @src='' )
-            and not(
-              @src=preceding-sibling::preproc:sym/@src
-            )
-          ]
-        ">
-
+      <xsl:for-each-group select="$program-symtable/preproc:sym[
+                                    @src and not( @src='' ) ]"
+                          group-by="@src">
         <xsl:message>
           <xsl:text>[summary] typesetting package </xsl:text>
           <xsl:value-of select="@src" />
           <xsl:text>...</xsl:text>
         </xsl:message>
 
-        <xsl:apply-templates
-          select="document( concat( @src, '.xmlo' ), . )/lv:*/lv:*" />
-      </xsl:for-each>
+        <xsl:variable name="pkg" as="element()"
+                      select="document( concat( @src, '.xmlo' ), . )/lv:*" />
+        <xsl:variable name="symtable" as="element( preproc:symtable )"
+                      select="$pkg/preproc:symtable" />
+
+        <xsl:variable name="symtable-map" as="map( xs:string, element( preproc:sym ) )"
+                      select="map:merge(
+                                for $sym in $symtable/preproc:sym
+                                  return map{ string( $sym/@name ) : $sym } )" />
+
+        <xsl:apply-templates select="$pkg/lv:*">
+          <xsl:with-param name="symtable-map" tunnel="yes"
+                          select="$symtable-map" />
+        </xsl:apply-templates>
+      </xsl:for-each-group>
 
       <!-- some general information -->
       <xsl:call-template name="summary-info" />
@@ -317,16 +341,9 @@
     </xsl:apply-templates>
 
     <!-- get a list of unique packages -->
-    <xsl:for-each select="
-        /lv:*/l:dep/preproc:sym[
-          @src
-          and not( @src='' )
-          and not(
-            @src=preceding-sibling::preproc:sym/@src
-          )
-        ]
-      ">
-
+    <xsl:for-each-group select="$program-symtable/preproc:sym[
+                                  @src and not( @src='' ) ]"
+                        group-by="@src">
       <!-- build package menu -->
       <xsl:variable name="result">
         <xsl:apply-templates select="$self" mode="gen-menu">
@@ -344,7 +361,7 @@
 
         <xsl:copy-of select="$result" />
       </xsl:if>
-    </xsl:for-each>
+    </xsl:for-each-group>
   </div>
 </xsl:template>
 
@@ -628,6 +645,8 @@
   FIXME: this is broken!
 -->
 <xsl:template match="lv:param|lv:const|lv:item" priority="1">
+  <xsl:param name="symtable-map" as="map(*)" tunnel="yes" />
+
   <xsl:variable name="class">
     <xsl:text>param</xsl:text>
 
@@ -656,10 +675,7 @@
                               local-name()" />
 
     <legend class="sym-{$type}">
-      <xsl:variable name="sym"
-                    select="/lv:*/preproc:symtable
-                              /preproc:sym[ @name=$name ]" />
-
+      <xsl:variable name="sym" select="$symtable-map( $name )" />
       <xsl:variable name="tex" select="$sym/@tex" />
 
       <!-- only show symbol if it is defined (no need for a default since
@@ -1168,12 +1184,12 @@
   @return anyOf match HTML
 -->
 <xsl:template match="lv:match[@anyOf]" mode="match-desc">
+  <xsl:param name="symtable-map" as="map(*)" tunnel="yes" />
+
   <xsl:variable name="anyOf" select="@anyOf" />
 
   <!-- attempt to locate the typedef -->
-  <xsl:variable name="typedef" select="
-      /lv:*/preproc:symtable/preproc:sym[ @name=$anyOf ]
-    " />
+  <xsl:variable name="typedef" select="$symtable-map( $anyOf )" />
 
   <xsl:text>match any value in </xsl:text>
 
@@ -1227,10 +1243,11 @@
   @return match HTML
 -->
 <xsl:template match="lv:match[@value]" mode="match-desc">
+  <xsl:param name="symtable-map" as="map(*)" tunnel="yes" />
+
   <xsl:variable name="value" select="@value" />
 
-  <xsl:variable name="sym"
-                select="/lv:*/preproc:symtable/preproc:sym[ @name=$value ]" />
+  <xsl:variable name="sym" select="$symtable-map( $value )" />
 
   <xsl:text>= </xsl:text>
 
@@ -1255,11 +1272,13 @@
 
 
 <xsl:template match="c:value-of" mode="match-desc" priority="5">
+  <xsl:param name="symtable-map" as="map(*)" tunnel="yes" />
+
   <xsl:variable name="name"
                 select="@name" />
 
   <xsl:variable name="sym" as="element( preproc:sym )"
-                select="/lv:*/preproc:symtable/preproc:sym[ @name=$name ]" />
+                select="$symtable-map( $name )" />
 
   <a href="#{$name}" class="sym-ref sym-{$sym/@type}">
     <xsl:value-of select="$name" />
@@ -1387,6 +1406,8 @@
 </xsl:template>
 
 <xsl:template match="lv:rate" mode="gen-rate-block">
+  <xsl:param name="symtable-map" as="map(*)" tunnel="yes" />
+
   <xsl:variable name="root" select="/" />
 
   <xsl:variable name="name" select="@yields" />
@@ -1401,9 +1422,7 @@
     </xsl:attribute>
 
     <legend class="sym-rate">
-      <xsl:variable name="tex" select="
-          /lv:*/preproc:symtable/preproc:sym[ @name=$name ]/@tex
-        " />
+      <xsl:variable name="tex" select="$symtable-map( $name )/@tex" />
 
       <!-- only show symbol if it is defined (no need for a default since
            defaults are specific to a given block) -->
@@ -1647,6 +1666,8 @@
 </xsl:template>
 
 <xsl:template name="ultra-breakdown-set" match="c:*" mode="ultra-breakdown" priority="1">
+  <xsl:param name="symtable-map" as="map(*)" tunnel="yes" />
+
   <xsl:param name="label" select="if ( @label ) then @label else @desc" />
   <xsl:param name="c" select="." />
 
@@ -1691,9 +1712,7 @@
 
       <xsl:if test="@name">
         <xsl:variable name="name" select="@name" />
-        <xsl:variable name="sym"
-                      select="/lv:*/preproc:symtable
-                                /preproc:sym[ @name=$name ]" />
+        <xsl:variable name="sym" select="$symtable-map( $name )" />
 
         <xsl:variable name="ref"
                       select="if ( $sym/@parent ) then
@@ -2102,9 +2121,7 @@
 <xsl:function name="preproc:sym-lookup" as="element( preproc:sym )?">
   <xsl:param name="name" as="xs:string" />
 
-  <!-- XXX: There's a linker bug where there may be duplicate symbols in
-       l:dep! -->
-  <xsl:sequence select="$program/l:dep/preproc:sym[ @name=$name ][1]" />
+  <xsl:sequence select="$program-symtable-map( $name )" />
 </xsl:function>
 
 
