fix bug with last commit, and better GUARD_MEMORY option

4 files changed, 10 insertions, 6 deletions

diff --git a/src/jsifier.js b/src/jsifier.js
index cd118644..d21e44d4 100644
--- a/src/jsifier.js
+++ b/src/jsifier.js
@@ -65,8 +65,8 @@ function JSify(data) {
   }
 
   function alignStruct(values, type) {
+    // XXX Need to add padding at the end of structures, using alignMemory()?
     dprint('types', 'alignStruct: ' + dump(type));
-    // XXX hardcoded ptr impl
     var ret = [];
     var typeData = TYPES[type];
     assertTrue(typeData);
diff --git a/src/library.js b/src/library.js
index 3d91926a..09c4d8f1 100644
--- a/src/library.js
+++ b/src/library.js
@@ -155,8 +155,8 @@ var Library = {
 
   llvm_umul_with_overflow_i32: function(x, y) {
     return {
-      f1: x*y,
-      f2: 0, // We never overflow... for now
+      f0: x*y,
+      f1: 0, // We never overflow... for now
     };
   },
 
diff --git a/src/runtime.js b/src/runtime.js
index 08e42362..250eb50a 100644
--- a/src/runtime.js
+++ b/src/runtime.js
@@ -6,6 +6,9 @@ RuntimeGenerator = {
   alloc: function(size, type) {
     var ret = type + 'TOP';
 //    ret += '; for (var i = 0; i < ' + size + '; i++) HEAP[' + type + 'TOP+i] = 0';
+    if (GUARD_MEMORY) {
+      ret += '; assert(' + size + ' > 0)';
+    }
     ret += '; ' + type + 'TOP += ' + size;
     if (QUANTUM_SIZE > 1) {
       ret += ';' + RuntimeGenerator.alignMemory(type + 'TOP');
@@ -16,7 +19,7 @@ RuntimeGenerator = {
   // An allocation that lives as long as the current function call
   stackAlloc: function(size) {
     var ret = RuntimeGenerator.alloc(size, 'STACK');
-    if (GUARD_STACK) {
+    if (GUARD_MEMORY) {
       ret += '; assert(STACKTOP < STACK_ROOT + STACK_MAX)';
     }
     return ret;
diff --git a/src/settings.js b/src/settings.js
index 660671fd..d79869f1 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -18,8 +18,9 @@ GUARD_SIGNS = 1; // Whether we make sure to convert unsigned values to signed va
                  // needed in some kinds of code.
 GUARD_LABELS = 0; // Whether we should throw if we encounter a bad __label__, i.e.,
                   // if code flow runs into a fault
-GUARD_STACK = 1; // Whether we should check that each allocation to the stack does not
-                 // exceed it's size
+GUARD_MEMORY = 1; // Whether we should check that each allocation to the stack does not
+                  // exceed it's size, whether all allocations (stack and static) are
+                  // of positive size, etc.
 
 // Code embetterments
 OPTIMIZE = 0; // Optimize llvm operations into js commands