optional stricter support for unsigned values +test

5 files changed, 47 insertions, 4 deletions

diff --git a/src/jsifier.js b/src/jsifier.js
index 7df0ba86..9a5d7121 100644
--- a/src/jsifier.js
+++ b/src/jsifier.js
@@ -516,11 +516,26 @@ function JSify(data) {
     dprint('phi', dump(item));
     return '__lastLabel__ == ' + getLabelId(item.label1) + ' ? ' + toNiceIdent(item.value1) + ' : ' + toNiceIdent(item.value2);
   });
+
+  function makeUnSign(value, type) {
+    if (type in INT_TYPES) {
+      return 'unSign(' + value + ', ' + type.substr(1) + ')';
+    } else {
+      return value;
+    }
+  }
+
   makeFuncLineZyme('mathop', function(item) { with(item) {
     dprint('mathop', 'mathop: ' + dump(item));
     ident = parseNumerical(ident);
     ident2 = parseNumerical(ident2);
-    switch (item.op) {
+    if (GUARD_SIGNS) {
+      if (op[0] == 'u' || (variant && variant[0] == 'u')) {
+        ident = makeUnSign(ident, type.text);
+        ident2 = makeUnSign(ident2, type.text);
+      }
+    }
+    switch (op) {
       case 'add': return ident + ' + ' + ident2;
       case 'sub': return ident + ' - ' + ident2;
       case 'sdiv': case 'udiv': return 'Math.floor(' + ident + ' / ' + ident2 + ')';
diff --git a/src/parseTools.js b/src/parseTools.js
index e7796b12..7cf0fa0b 100644
--- a/src/parseTools.js
+++ b/src/parseTools.js
@@ -53,9 +53,11 @@ function toNiceIdent(ident) {
   return ident.replace(/[" \.@%:<>,\*]/g, '_');
 }
 
+INT_TYPES = searchable('i1', 'i8', 'i16', 'i32', 'i64');
+FLOAT_TYPES = searchable('float', 'double');
+
 function isNumberType(type) {
-  var types = ['i1', 'i8', 'i16', 'i32', 'i64', 'float', 'double'];
-  return types.indexOf(type) != -1;
+  return type in INT_TYPES || type in FLOAT_TYPES;
 }
 
 function isStructPointerType(type) {
diff --git a/src/preamble.js b/src/preamble.js
index d61a8ce5..e1036b8e 100644
--- a/src/preamble.js
+++ b/src/preamble.js
@@ -156,7 +156,7 @@ function __formatString() {
   while (curr != 0) {
     curr = HEAP[textIndex];
     next = HEAP[textIndex+1];
-    if (curr == '%'.charCodeAt(0) && ['d', 'f', '.'].indexOf(String.fromCharCode(next)) != -1) {
+    if (curr == '%'.charCodeAt(0) && ['d', 'u', 'f', '.'].indexOf(String.fromCharCode(next)) != -1) {
       var argText = String(arguments[argIndex]);
       // Handle very very simply formatting, namely only %.Xf
       if (next == '.'.charCodeAt(0)) {
@@ -169,6 +169,8 @@ function __formatString() {
         argText += '00000000000'; // padding
         argText = argText.substr(0, dotIndex+1+limit);
         textIndex += 2;
+      } else if (next == 'u'.charCodeAt(0)) {
+        argText = String(unSign(arguments[argIndex], 32));
       }
       argText.split('').forEach(function(chr) {
         ret.push(chr.charCodeAt(0));
@@ -260,5 +262,12 @@ function intArrayFromString(stringy) {
   return ret;
 }
 
+// Converts a value we have as signed, into an unsigned value. For
+// example, -1 in int32 would be a very large number as unsigned.
+function unSign(value, bits) {
+  if (value >= 0) return value;
+  return 2*Math.abs(1 << (bits-1)) + value;
+}
+
 // === Body ===
 
diff --git a/src/settings.js b/src/settings.js
index f6282ed4..815832ed 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -13,6 +13,10 @@ QUANTUM_SIZE = 1; // This is the size of an individual field in a structure. 1 w
                   // way to prevent problems with that is to set QUANTUM_SIZE to 8.
                   // See the 'copyop' automatic test.
 
+GUARD_SIGNS = 1; // Whether we make sure to convert unsigned values to signed values.
+                 // Decreases performance with additional runtime checks. Might not be
+                 // needed in some kinds of code.
+
 // Code embetterments
 OPTIMIZE = 1; // Optimize llvm operations into js commands
 RELOOP = 0; // Recreate js native loops from llvm data XXX - disabled pending optimizing rewrite
diff --git a/tests/runner.py b/tests/runner.py
index 08560fd8..8b71b223 100644
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -132,6 +132,19 @@ class T(unittest.TestCase):
         '''
         self.do_test(src, '*5,23,10,19,121,1,37,1,0*')
 
+    def test_unsigned(self):
+        src = '''
+          #include <stdio.h>
+          int main()
+          {
+            int varey = 100;
+            unsigned int MAXEY = -1, MAXEY2 = -77;
+            printf("*%u,%d,%u*\\n", MAXEY, varey >= MAXEY, MAXEY2); // 100 >= -1? not in unsigned!
+            return 0;
+          }
+        '''
+        self.do_test(src, '*4294967295,0,4294967219*')
+
     def test_floatvars(self):
         src = '''
           #include <stdio.h>