From 1f24cfdf2565974e0df6a1c4187c98cda943db2c Mon Sep 17 00:00:00 2001
From: Mike Gerwitz <mike.gerwitz@ryansg.com>
Date: Thu, 22 Jul 2021 13:39:28 -0400
Subject: [PATCH] Remove :map: sym-dep generation

This was incorrect to begin with---it does not make sense that an input
mapping should depend upon the identifier that it maps to, in the sense that
we make use of these dependencies.  If we add weak symbol references in the
future, then this can be reintroduced.

By removing this, we free tameld from having to perform the check itself.

.rev-xmlo bumped to force rebuilding of object files since the linker now
expects that no such dependencies will exist within them.
---
 .rev-xmlo                         |  2 +-
 RELEASES.md                       | 12 ++++++++++++
 src/current/compiler/map.xsl      | 12 +++---------
 tamer/src/obj/xmlo/asg_builder.rs | 27 ++-------------------------
 4 files changed, 18 insertions(+), 35 deletions(-)

diff --git a/.rev-xmlo b/.rev-xmlo
index 97d737a7..ab51bcd0 100644
--- a/.rev-xmlo
+++ b/.rev-xmlo
@@ -1,4 +1,4 @@
 # This number is incremented for every compiler change to force rebuilding
 # of xmlo files.
-3
+4
 
diff --git a/RELEASES.md b/RELEASES.md
index 92d18e39..284b18aa 100644
--- a/RELEASES.md
+++ b/RELEASES.md
@@ -14,6 +14,18 @@ commits that introduce the changes.  To make a new release, run
 `tools/mkrelease`, which will handle updating the heading for you.
 
 
+NEXT
+====
+Compiler
+--------
+- Input mappings will no longer emit the destination param as a dependency.
+
+Linker
+------
+- Remove exception for input map dependency processing (now that compiler no
+  longer emits such a dependency).
+
+
 v18.0.3 (2021-07-21)
 ====================
 This release significantly improves the performance of executables
diff --git a/src/current/compiler/map.xsl b/src/current/compiler/map.xsl
index a979cff3..6fcba378 100644
--- a/src/current/compiler/map.xsl
+++ b/src/current/compiler/map.xsl
@@ -348,9 +348,7 @@
 
 
 <template match="lvm:pass" mode="preproc:depgen" priority="5">
-  <preproc:sym-dep name=":map:{@name}">
-    <preproc:sym-ref name="{@name}" lax="true" />
-  </preproc:sym-dep>
+  <preproc:sym-dep name=":map:{@name}" />
 </template>
 
 <template match="lvm:pass[ root(.)/@lvmc:type = 'retmap' ]"
@@ -408,9 +406,7 @@
 <template match="lvm:map[ @from
                           and root(.)/@lvmc:type = 'map' ]"
               mode="preproc:depgen" priority="5">
-  <preproc:sym-dep name=":map:{@to}">
-    <preproc:sym-ref name="{@to}" lax="true" />
-  </preproc:sym-dep>
+  <preproc:sym-dep name=":map:{@to}" />
 </template>
 
 <template match="lvm:map[ @from
@@ -632,9 +628,7 @@
 </template>
 
 <template match="lvm:map[ * ]" mode="preproc:depgen" priority="5">
-  <preproc:sym-dep name=":map:{@to}">
-    <preproc:sym-ref name="{@to}" lax="true" />
-  </preproc:sym-dep>
+  <preproc:sym-dep name=":map:{@to}" />
 </template>
 
 <template match="lvm:map[ *
diff --git a/tamer/src/obj/xmlo/asg_builder.rs b/tamer/src/obj/xmlo/asg_builder.rs
index 00c2443e..635a503f 100644
--- a/tamer/src/obj/xmlo/asg_builder.rs
+++ b/tamer/src/obj/xmlo/asg_builder.rs
@@ -212,15 +212,8 @@ where
                 }
 
                 XmloEvent::SymDeps(sym, deps) => {
-                    // Maps should not pull in symbols since we may end up
-                    // mapping to params that are never actually used.
-                    // TODO: Can these just be removed from the xmlo files
-                    //   rather than adding exceptions?
-                    // TODO: No string comparison.
-                    if !sym.starts_with(":map:") {
-                        for dep_sym in deps {
-                            self.add_dep_lookup(sym, dep_sym);
-                        }
+                    for dep_sym in deps {
+                        self.add_dep_lookup(sym, dep_sym);
                     }
                 }
 
@@ -450,22 +443,6 @@ mod test {
         assert!(sut.has_dep(node_from, node_to2));
     }
 
-    #[test]
-    fn ignores_map_sym_deps() {
-        let mut sut = Sut::new();
-
-        let sym_from = symbol_dummy!(1, ":map:sym");
-        let sym_to = symbol_dummy!(2, "to");
-
-        let evs = vec![Ok(XmloEvent::SymDeps(&sym_from, vec![&sym_to]))];
-
-        let _ = sut
-            .import_xmlo(evs.into_iter(), SutState::new())
-            .expect("unexpected failure");
-
-        assert!(sut.lookup(&sym_from).is_none());
-    }
-
     #[test]
     fn sym_decl_with_src_not_added_and_populates_found() {
         let mut sut = Sut::new();