Fix MIN_INT values when checking integer ranges

Fixes: emscripten-core#19251

Author: sbc100

src/runtime_debug.js

@@ -142,11 +142,11 @@ var MAX_UINT32 = (2 ** 32) - 1;
 var MAX_UINT53 = (2 ** 53) - 1;
 var MAX_UINT64 = (2 ** 64) - 1;
 
-var MIN_INT8  = - (2 ** ( 8 - 1)) + 1;
-var MIN_INT16 = - (2 ** (16 - 1)) + 1;
-var MIN_INT32 = - (2 ** (32 - 1)) + 1;
-var MIN_INT53 = - (2 ** (53 - 1)) + 1;
-var MIN_INT64 = - (2 ** (64 - 1)) + 1;
+var MIN_INT8  = - (2 ** ( 8 - 1));
+var MIN_INT16 = - (2 ** (16 - 1));
+var MIN_INT32 = - (2 ** (32 - 1));
+var MIN_INT53 = - (2 ** (53 - 1));
+var MIN_INT64 = - (2 ** (64 - 1));
 
 function checkInt(value, bits, min, max) {
   assert(Number.isInteger(Number(value)), `attempt to write non-integer (${value}) into integer heap`);

test/core/test_getValue_setValue.cpp

@@ -4,6 +4,7 @@
 // found in the LICENSE file.
 
 #include <emscripten.h>
+#include <stdint.h>
 
 int main() {
   char buffer_char[8] = { 'x' };
@@ -30,6 +31,28 @@ int main() {
     ptr = Module['getValue']($1, '*');
     out('ptr: 0x' + ptr.toString(16) + ' ' + typeof(ptr));
 #endif
-  }, buffer_char, buffer_ptr);
+
+    /* In debug mode we check the limits of input value */
+    var min = $2;
+    var max = $3;
+    setValue($1, max, 'i8');
+    setValue($1, min, 'i8');
+#ifdef ASSERTIONS_2
+    function checkAsserts(f, expected) {
+      try {
+        f();
+      } catch(e) {
+        assert(e.message.includes(expected), "expected assertion to include:" + expected);
+        return;
+      }
+      assert(false, "expected assertion");
+    }
+    checkAsserts(() => setValue($1, max + 1, 'i8'), "value (256) too large to write as 8-bit value");
+    checkAsserts(() => setValue($1, min - 1, 'i8'), "value (-129) too small to write as 8-bit value");
+#else
+    setValue($1, max + 1, 'i8');
+    setValue($1, min - 1, 'i8');
+#endif
+  }, buffer_char, buffer_ptr, INT8_MIN, UINT8_MAX);
 }
 

test/test_core.py

@@ -7068,11 +7068,17 @@ def test(args=None, asserts=False):
     # see that direct usage (not on module) works. we don't export, but the use
     # keeps it alive through JSDCE
     test(args=['-DDIRECT'])
+
+    # Test with ASSERTIONS=2 we check the limits of value passed to setValue
+    self.set_setting('ASSERTIONS', 2)
+    test(args=['-DDIRECT', '-DASSERTIONS_2'])
+
     # see that with assertions, we get a nice error message
     self.set_setting('EXPORTED_RUNTIME_METHODS', [])
     self.set_setting('ASSERTIONS')
     test(asserts=True)
     self.set_setting('ASSERTIONS', 0)
+
     # see that when we export them, things work on the module
     self.set_setting('EXPORTED_RUNTIME_METHODS', ['getValue', 'setValue'])
     test()