better handling of NULL in printf, and varargs

src/parser.js

@@ -1933,7 +1933,7 @@ function JSify(data) {
       return makePointer(JSON.stringify(makeEmptyStruct(type)));
     } else if (value.text[0] == '"') {
       value.text = value.text.substr(1, value.text.length-2);
-      return makePointer(JSON.stringify(parseLLVMString(value.text)));
+      return makePointer(JSON.stringify(parseLLVMString(value.text)) + ' /* ' + value.text + '*/');
     } else {
       // Gets an array of constant items, separated by ',' tokens
       function handleSegments(tokens) {
@@ -2062,8 +2062,6 @@ function JSify(data) {
 
         func.splitItems -= lines.length;
         if (func.splitItems === 0) {
-          postJSOptimize(func);
-
           // Final recombination
           //print('zz params::::: ' + JSON.stringify(func.params));
           //print('zz params::::: ' + JSON.stringify(parseParamTokens(func.params.item[0].tokens)));
@@ -2075,11 +2073,15 @@ function JSify(data) {
               return null;
             }
             return toNiceIdent(param.ident);
-          }).filter(function(param) { return param != null }).join(', ');
+          }).filter(function(param) { return param != null });;
 
-          func.JS = '\nfunction ' + func.ident + '(' + params + ') {\n';
+          func.JS = '\nfunction ' + func.ident + '(' + params.join(', ') + ') {\n';
           if (LABEL_DEBUG) func.JS += "  print(INDENT + ' Entering: " + func.ident + "'); INDENT += '  ';\n";
 
+          if (hasVarArgs) {
+            func.JS += '  __numArgs__ = ' + params.length + ';\n';
+          }
+
           // Walk function blocks and generate JS
           function walkBlock(block, indent) {
             if (!block) return '';
@@ -2136,11 +2138,6 @@ function JSify(data) {
       return ret;
     },
   });
-  function postJSOptimize(func) {
-    // Some optimizations are easier to apply after JS-ing the code - for example, a lot
-    // of stuff can end up as   x = y;  for example, bitcasts, or nativized, etc. If we
-    // we to optimize pre-JS, we would need to be aware of all of that.
-  }
 
   function getVarData(funcData, ident) {
     if (funcData.variables[ident]) {
@@ -2448,14 +2445,12 @@ function JSify(data) {
     return ident;
   });
   function makeFunctionCall(ident, params) {
-    //print('// zz makeFC: ' + ident + ' : ' + dump(params));
-
     // Special cases
     if (ident == '_llvm_va_start') {
       if (SAFE_HEAP) {
-        return 'SAFE_HEAP_STORE(' + params[0].ident + ', Pointer_make(Array.prototype.slice.call(arguments, 1).concat([0]), 0))';
+        return 'SAFE_HEAP_STORE(' + params[0].ident + ', Pointer_make(Array.prototype.slice.call(arguments, __numArgs__).concat([0]), 0))';
       } else {
-        return 'HEAP[' + params[0].ident + '] = Pointer_make(Array.prototype.slice.call(arguments, 1).concat([0]), 0)'; // XXX 1
+        return 'HEAP[' + params[0].ident + '] = Pointer_make(Array.prototype.slice.call(arguments, __numArgs__).concat([0]), 0)';
       }
     } else if (ident == '_llvm_va_end') {
       return ';'

src/preamble.js

@@ -8,8 +8,8 @@ var __THREW__ = false; // Used in checking for thrown exceptions.
 
 var __ATEXIT__ = [];
 
-var HEAP = [0];
-var HEAPTOP = 1; // Leave 0 as an invalid address, 'NULL'
+var HEAP = intArrayFromString('(null)'); // So printing %s of NULL gives '(null)'
+var HEAPTOP = HEAP.length+1; // Leave 0 as an invalid address, 'NULL'
 
 #if SAFE_HEAP
 // Semi-manual memory corruption debugging

tests/runner.py

@@ -234,11 +234,11 @@ class T(unittest.TestCase):
             printf("%d", atoi(argv[3])+2);
             const char *foolingthecompiler = "\\rabcd";
             printf("%d", strlen(foolingthecompiler)); // Tests parsing /0D in llvm - should not be a 0 (end string) then a D!
-            printf("%s*", NULL); // Should print nothing, not the string at address 0, which is a real address for us!
+            printf("%s*", NULL); // Should print '(null)', not the string at address 0, which is a real address for us!
             return 0;
           }
         '''
-        self.do_test(src, '*4*wowie*too*76*5**', ['wowie', 'too', '74'], lambda x: x.replace('\n', '*'))
+        self.do_test(src, '*4*wowie*too*76*5*(null)*', ['wowie', 'too', '74'], lambda x: x.replace('\n', '*'))
 
     def test_funcs(self):
         src = '''
@@ -613,12 +613,24 @@ class T(unittest.TestCase):
             va_end(v);
           }
 
+          void vary2(char color, const char *s, ...)
+          {
+            va_list v;
+            va_start(v, s);
+            char d[21];
+            d[0] = color;
+            vsnprintf(d+1, 20, s, v);
+            puts(d);
+            va_end(v);
+          }
+
           int main() {
             vary("*cheez: %d+%d*", 10, 24);
+            vary2('Q', "%d*", 85);
             return 0;
           }
           '''
-        self.do_test(src, '*cheez: 10+24*')
+        self.do_test(src, '*cheez: 10+24*\nQ85*')
 
     def test_atexit(self):
         src = '''