From 01f2bba2f4a0125d066e50e802c474a40bd37a32 Mon Sep 17 00:00:00 2001
From: Sei Lisa <sei-lisa@email.fake>
Date: Tue, 3 Mar 2015 00:49:14 +0100
Subject: [PATCH] Make *-2 and *2 only work for local variables. Needed an
 adition to the parser.

---
 lslopt/lslfoldconst.py | 22 +++++++++-------------
 lslopt/lslparse.py     |  2 +-
 2 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/lslopt/lslfoldconst.py b/lslopt/lslfoldconst.py
index 8b6a719..ad0f8a6 100644
--- a/lslopt/lslfoldconst.py
+++ b/lslopt/lslfoldconst.py
@@ -540,8 +540,8 @@ class foldconst(object):
                     # expr * 1  ->  expr
                     # expr * 0  ->  0  if side-effect free
                     # expr * -1  -> -expr
-                    # ident * 2  ->  ident+ident
-                    # ident * -2  ->  -(ident + ident) (this can turn out to be counter-productive if ident is not a local)
+                    # ident * 2  ->  ident + ident (no gain except if ident is local)
+                    # ident * -2  ->  -(ident + ident) (this is counter-productive if ident is not local)
                     # expr/1  ->  expr
                     # expr/-1  ->  -expr
                     if nt == '*' and child[b]['t'] in ('float', 'integer') \
@@ -561,17 +561,13 @@ class foldconst(object):
                                 node['SEF'] = True
                             return
                         # only -2, 2 remain
-                        if child[a]['nt'] == 'IDENT':
-                            # FIXME: The -2 case is counter-productive if the var is not local.
-                            # We don't have info on whether a variable is local yet.
-                            # Or maybe we do; got to check. Disabled for now.
-                            if val != -2:
-                                child[b] = child[a].copy()
-                                node['nt'] = '+'
-                                if val == -2:
-                                    parent[index] = {'nt':'NEG', 't':node['t'], 'ch':[node]}
-                                    if 'SEF' in node:
-                                        parent[index]['SEF'] = True
+                        if child[a]['nt'] == 'IDENT' and 'Local' in self.symtab[child[a]['scope']][child[a]['name']]:
+                            child[b] = child[a].copy()
+                            node['nt'] = '+'
+                            if val == -2:
+                                parent[index] = {'nt':'NEG', 't':node['t'], 'ch':[node]}
+                                if 'SEF' in node:
+                                    parent[index]['SEF'] = True
                             return
                 return
 
diff --git a/lslopt/lslparse.py b/lslopt/lslparse.py
index e989fca..b0535c5 100644
--- a/lslopt/lslparse.py
+++ b/lslopt/lslparse.py
@@ -1335,7 +1335,7 @@ class parser(object):
                 decl['ch'] = [self.autocastcheck(self.Parse_expression(), typ)]
             self.expect(';')
             self.NextToken()
-            self.AddSymbol('v', self.scopeindex, name, Type=typ)
+            self.AddSymbol('v', self.scopeindex, name, Type=typ, Local=True)
             return decl
 
         # If none of the above, it must be an expression.