From b82294b1bda0fcb2c0bf2594e4642d53ae0f4b87 Mon Sep 17 00:00:00 2001
From: Mike Gerwitz <mike.gerwitz@ryansg.com>
Date: Mon, 16 Oct 2023 11:34:46 -0400
Subject: [PATCH] preproc/symtable (preproc:symtable-complete): Do not
 re-process imported symbols

It's embarrassing how much time this saved on builds.

This apparently has always been doing a linear scan on the entire symbol
table for _every single param in the symbol table_, including those that
were imported.  This is not only unnecessary, but has no effect on the end
result of the system.

This cut build times almost in half, due to the number of symbols in some of
our packages.  All for unnecessary work.

Like most things that have quadratic (or polynomial) time complexity, they
don't show up during initial development, and are hard to even profile for,
because their effects are so small.  Now that our system has grown
substantially, it had a massive effect.

DEV-15114
---
 src/current/include/preproc/symtable.xsl | 5 +++--
 src/symtable/symbols.xsl                 | 5 +++++
 test/symtable/symbols.xspec              | 5 +++++
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/current/include/preproc/symtable.xsl b/src/current/include/preproc/symtable.xsl
index bac735d0..8f1ca9f5 100644
--- a/src/current/include/preproc/symtable.xsl
+++ b/src/current/include/preproc/symtable.xsl
@@ -843,7 +843,8 @@
 </template>
 
 
-<template match="preproc:sym[ @type='param' ]" mode="preproc:symtable-complete" priority="5">
+<template mode="preproc:symtable-complete" priority="5"
+          match="preproc:sym[ @need-resolve-dtype='true' ]">
   <param name="syms" as="element( preproc:sym )*" />
 
   <!-- attempt to derive type information from a typedef -->
@@ -863,7 +864,7 @@
 
   <!-- complete datatype with primitive -->
   <copy>
-    <sequence select="@*" />
+    <sequence select="@*[ not( local-name() = 'need-resolve-dtype' ) ]" />
     <attribute name="dtype" select="$typedef/@dtype" />
   </copy>
 </template>
diff --git a/src/symtable/symbols.xsl b/src/symtable/symbols.xsl
index e35ab08c..b96a80b1 100644
--- a/src/symtable/symbols.xsl
+++ b/src/symtable/symbols.xsl
@@ -345,11 +345,16 @@
   <variable name="dim" as="xs:integer"
             select="_symtable:str-to-dim( @set )" />
 
+  <!-- @need-resolve-dtype flags this symbol as needing further processing
+       to resolve @dtype, which we cannot do until we know we have a full
+       symbol table that includes the necessary typedef referenced by the
+       current value of @dtype  -->
   <preproc:sym type="param"
                name="{@name}"
                dim="{$dim}"
                desc="{@desc}"
                dtype="{@type}"
+               need-resolve-dtype="true"
                default="{@default}"
                tex="{@sym}" />
 </template>
diff --git a/test/symtable/symbols.xspec b/test/symtable/symbols.xspec
index 9f67ccdf..b6e62cd7 100644
--- a/test/symtable/symbols.xspec
+++ b/test/symtable/symbols.xspec
@@ -63,6 +63,7 @@
                    dim="1"
                    desc="Vector param"
                    dtype="footype"
+                   need-resolve-dtype="true"
                    default=""
                    tex="" />
 
@@ -71,6 +72,7 @@
                    dim="2"
                    desc="Matrix param with TeX"
                    dtype="tex"
+                   need-resolve-dtype="true"
                    default=""
                    tex="\tex" />
 
@@ -79,6 +81,7 @@
                    dim="0"
                    desc="Scalar param (implicit)"
                    dtype="bar"
+                   need-resolve-dtype="true"
                    default=""
                    tex="" />
 
@@ -87,6 +90,7 @@
                    dim="0"
                    desc="Scalar param (explicit)"
                    dtype="bar"
+                   need-resolve-dtype="true"
                    default=""
                    tex="" />
 
@@ -95,6 +99,7 @@
                    dim="-1"
                    desc="Unknown dimension"
                    dtype="wtf"
+                   need-resolve-dtype="true"
                    default=""
                    tex="" />
     </expect>