Fixed and found some constexpr pruning

Signed-off-by: Luke Quinn <[email protected]>

Author: lquinn2015

backends/cpp_hart_gen/lib/constexpr_pass.rb

@@ -13,8 +13,9 @@ def constexpr?(symtab)
   class IdAst
     def constexpr?(symtab)
       sym = symtab.get(name)
-      return true if sym.nil? # assuming undefined syms are local (be sure to type check first!!)
+      return true if sym.nil?
       return true if sym.is_a?(Type)
+      return false if sym.value.nil? # assuming undefined syms are local (be sure to type check first!!)
 
       if sym.param?
         symtab.cfg_arch.params_with_value.any? { |p| p.name == text_value }

backends/cpp_hart_gen/lib/gen_cpp.rb

@@ -399,6 +399,8 @@ def gen_cpp(symtab, indent = 0, indent_spaces: 2)
       lines = []
       symtab.push(nil)
       init.add_symbol(symtab)
+      symtab.get(init.lhs.text_value).value = nil
+
       stmts.each do |s|
         lines << s.gen_cpp(symtab, indent_spaces, indent_spaces:)
       end

lib/idl/passes/prune.rb

@@ -85,7 +85,8 @@ def prune(symtab)
             init.prune(symtab),
             condition.prune(symtab),
             update.prune(symtab),
-            stmts.map { |s| s.prune(symtab) }
+            #stmts.map { |s| s.prune(symtab) } #TODO need to not prune a = a + 1  since is known for each loop iter but should accumulate
+            stmts.map { |s| s.dup() }
           )
       ensure
         symtab.pop