From 0a70a77f42b48ca2ab4d48e4bc86542b63e25843 Mon Sep 17 00:00:00 2001
From: mwilliams <mwilliams@fb.com>
Date: Thu, 18 Apr 2013 19:21:40 -0700
Subject: [PATCH] Fix an issue with exit/include/etc

Various unary operators have arbitrary effects. Dont assume we
know anything about locals when we see one.

Fix an expect for differences in line numbers.

Prevent a use of an undefined constant from being optimized away.
---
 hphp/compiler/analysis/alias_manager.cpp      | 28 ++++++++++++++++---
 .../quick/exception_destructor_3.php.expectf  |  2 +-
 hphp/test/quick/exception_many_locals.php     |  1 +
 3 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/hphp/compiler/analysis/alias_manager.cpp b/hphp/compiler/analysis/alias_manager.cpp
index 1d1de4212..e87631d9d 100644
--- a/hphp/compiler/analysis/alias_manager.cpp
+++ b/hphp/compiler/analysis/alias_manager.cpp
@@ -601,6 +601,10 @@ void AliasManager::cleanRefs(ExpressionPtr e,
                              ExpressionPtrList::reverse_iterator it,
                              ExpressionPtrList::reverse_iterator &end,
                              int depth) {
+  if (e->is(Expression::KindOfUnaryOpExpression) &&
+      e->getLocalEffects() == Expression::UnknownEffect) {
+    return;
+  }
   if (e->is(Expression::KindOfAssignmentExpression) ||
       e->is(Expression::KindOfBinaryOpExpression) ||
       e->is(Expression::KindOfUnaryOpExpression)) {
@@ -752,6 +756,7 @@ void AliasManager::killLocals() {
         continue;
 
       case Expression::KindOfUnaryOpExpression:
+        if (e->getLocalEffects() == Expression::UnknownEffect) goto kill_it;
         cleanInterf(spc(UnaryOpExpression, e)->getExpression(),
                     ++it, end, depth);
         continue;
@@ -848,9 +853,14 @@ int AliasManager::checkInterf(ExpressionPtr rv, ExpressionPtr e,
       return testAccesses(e, rv, forLval);
     }
 
+    case Expression::KindOfUnaryOpExpression:
+      if (e->getLocalEffects() == Expression::UnknownEffect) {
+        isLoad = false;
+        return InterfAccess;
+      }
+      // fall through
     case Expression::KindOfAssignmentExpression:
-    case Expression::KindOfBinaryOpExpression:
-    case Expression::KindOfUnaryOpExpression: {
+    case Expression::KindOfBinaryOpExpression: {
       isLoad = false;
       ExpressionPtr var = e->getStoreVariable();
       int access = testAccesses(var, rv, forLval);
@@ -899,6 +909,10 @@ int AliasManager::checkAnyInterf(ExpressionPtr e1, ExpressionPtr e2,
     case Expression::KindOfAssignmentExpression:
     case Expression::KindOfBinaryOpExpression:
     case Expression::KindOfUnaryOpExpression:
+      if (e1->getLocalEffects() == Expression::UnknownEffect) {
+        isLoad = false;
+        return InterfAccess;
+      }
       e1 = e1->getStoreVariable();
       if (!e1 || !e1->hasContext(Expression::OprLValue)) return DisjointAccess;
       break;
@@ -1274,6 +1288,7 @@ ExpressionPtr AliasManager::canonicalizeNode(
           }
           case Expression::KindOfUnaryOpExpression: {
             UnaryOpExpressionPtr u = spc(UnaryOpExpression, rep);
+            assert(u->getOp() == T_INC || u->getOp() == T_DEC);
             if (Option::EliminateDeadCode) {
               if (u->getActualType() && u->getActualType()->isInteger()) {
                 ExpressionPtr val = u->getExpression()->clone();
@@ -1720,7 +1735,8 @@ ExpressionPtr AliasManager::canonicalizeNode(
                 default:
                   break;
               }
-              always_assert(alt->getKindOf() == uop->getExpression()->getKindOf());
+              always_assert(alt->getKindOf() ==
+                            uop->getExpression()->getKindOf());
               uop->getExpression()->setCanonID(alt->getCanonID());
             } else {
               uop->getExpression()->setCanonID(m_nextID++);
@@ -1729,7 +1745,11 @@ ExpressionPtr AliasManager::canonicalizeNode(
           add(m_accessList, e);
           break;
         default:
-          getCanonical(e);
+          if (uop->getLocalEffects() == Expression::UnknownEffect) {
+            add(m_accessList, e);
+          } else {
+            getCanonical(e);
+          }
           break;
       }
       break;
diff --git a/hphp/test/quick/exception_destructor_3.php.expectf b/hphp/test/quick/exception_destructor_3.php.expectf
index d6472d14c..591201215 100644
--- a/hphp/test/quick/exception_destructor_3.php.expectf
+++ b/hphp/test/quick/exception_destructor_3.php.expectf
@@ -3,5 +3,5 @@ main() starting
 Calling foo()
 Calling bar()
 In ThrowDestruct2::__destruct()
-HipHop Warning: Destructor threw an object exception: exception 'Ex2' with message 'Exception leaked out of ThrowDestruct2::__destruct()' in %a on line 37
+HipHop Warning: Destructor threw an object exception: exception 'Ex2' with message 'Exception leaked out of ThrowDestruct2::__destruct()' in %a on line %d
 After bar()
diff --git a/hphp/test/quick/exception_many_locals.php b/hphp/test/quick/exception_many_locals.php
index 88308fb17..2ae3f893b 100644
--- a/hphp/test/quick/exception_many_locals.php
+++ b/hphp/test/quick/exception_many_locals.php
@@ -24,6 +24,7 @@ function main() {
     $o7 = $o; // use callee saved
     $p = 5;
     $x = CONSTANT;
+    echo $x;
   } catch (Exception $e) {
     echo "Caught: " . $e->getMessage() . "\n";
   }