Fix swaps and other misoptimizations

This undoes 454d44e85f

lslopt/lsldeadcode.py

@@ -322,13 +322,18 @@ class deadcode(object):
             node = sym['W']
             nt = node.nt
 
-            while nt == 'IDENT':
+            # This screws up swaps. See
-                # Follow the chain of identifiers all the way to the original
+            # unit_tests/regression.suite/aggressive-local-removal.lsl
-                if self.symtab[node.scope][node.name].get('W', False) is False:
+            # It can't be done without a reliable CFG-based method (SSA or
-                    return sym
+            # the like).
-                sym = self.symtab[node.scope][node.name]
+
-                node = sym['W']
+#            while nt == 'IDENT':
-                nt = node.nt
+#                # Follow the chain of identifiers all the way to the original
+#                if self.symtab[node.scope][node.name].get('W', False) is False:
+#                    return sym
+#                sym = self.symtab[node.scope][node.name]
+#                node = sym['W']
+#                nt = node.nt
 
             if nt == 'CONST':
                 tcurnode = curnode.t

unit_tests/coverage.suite/inline-4.out

@@ -17,8 +17,9 @@ default
         {
             {
                 {
+                    integer f2param = 4;
                     {
-                        llOwnerSay("f2:" + "4");
+                        llOwnerSay("f2:" + (string)f2param);
                     }
                 }
                 {

unit_tests/regression.suite/declaration-chain-dcr.out

@@ -2,6 +2,9 @@ default
 {
     state_entry()
     {
-        llOwnerSay("x" + "3");
+        integer b = 3;
+        integer c = b;
+        integer d = c;
+        llOwnerSay("x" + (string)d);
     }
 }