3 files changed, 34 insertions, 4 deletions
diff --git a/src/library.js b/src/library.js
index 0574bb8d..4bbeeee5 100644
--- a/src/library.js
+++ b/src/library.js
@@ -4604,16 +4604,20 @@ LibraryManager.library = {
   _ZTIPv: [0],
 
   llvm_uadd_with_overflow_i32: function(x, y) {
+    x = x>>>0;
+    y = y>>>0;
     return {
-      f0: x+y,
-      f1: 0 // We never overflow... for now
+      f0: (x+y)>>>0,
+      f1: x+y > 4294967295
     };
   },
 
   llvm_umul_with_overflow_i32: function(x, y) {
+    x = x>>>0;
+    y = y>>>0;
     return {
-      f0: x*y,
-      f1: 0 // We never overflow... for now
+      f0: (x*y)>>>0,
+      f1: x*y > 4294967295
     };
   },
 
diff --git a/tests/cases/uadd_overflow.ll b/tests/cases/uadd_overflow.ll
new file mode 100644
index 00000000..a808b9de
--- /dev/null
+++ b/tests/cases/uadd_overflow.ll
@@ -0,0 +1,25 @@
+; ModuleID = 'tests/hello_world.bc'
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32-S128"
+target triple = "i386-pc-linux-gnu"
+
+@.str2 = private constant [9 x i8] c"*%d,%d*\0A\00", align 1 ; [#uses=1]
+
+; [#uses=0]
+define i32 @main() {
+entry:
+  %retval = alloca i32, align 4                   ; [#uses=1 type=i32*]
+  %mul7 = bitcast i32 -259741926 to i32
+  %shl10 = shl i32 4014, 16
+  %uadd1 = tail call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 %mul7, i32 %shl10)
+  %a0 = extractvalue { i32, i1 } %uadd1, 0
+  %a1 = extractvalue { i32, i1 } %uadd1, 1
+  %a2 = zext i1 %a1 to i32
+  call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([9 x i8]* @.str2, i32 0, i32 0), i32 %a0, i32 %a2) ; [#uses=0]
+  ret i32 1
+}
+
+; [#uses=1]
+declare i32 @printf(i8*, ...)
+
+declare { i32, i1 } @llvm.uadd.with.overflow.i32(i32, i32) nounwind readnone
+
diff --git a/tests/cases/uadd_overflow.txt b/tests/cases/uadd_overflow.txt
new file mode 100644
index 00000000..dcda9240
--- /dev/null
+++ b/tests/cases/uadd_overflow.txt
@@ -0,0 +1 @@
+*3319578,1*