4 files changed, 70 insertions, 0 deletions
diff --git a/lib/Analysis/NaCl/PNaClABIVerifyFunctions.cpp b/lib/Analysis/NaCl/PNaClABIVerifyFunctions.cpp
index a59f6f6682..b17fc1ab69 100644
--- a/lib/Analysis/NaCl/PNaClABIVerifyFunctions.cpp
+++ b/lib/Analysis/NaCl/PNaClABIVerifyFunctions.cpp
@@ -19,6 +19,7 @@
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Metadata.h"
+#include "llvm/IR/Operator.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/raw_ostream.h"
 
@@ -322,6 +323,21 @@ const char *PNaClABIVerifyFunctions::checkInstruction(const Instruction *Inst) {
         !isValidScalarOperand(Inst->getOperand(OpNum)))
       return "bad operand";
   }
+
+  // Check arithmetic attributes.
+  if (const OverflowingBinaryOperator *Op =
+          dyn_cast<OverflowingBinaryOperator>(Inst)) {
+    if (Op->hasNoUnsignedWrap())
+      return "has \"nuw\" attribute";
+    if (Op->hasNoSignedWrap())
+      return "has \"nsw\" attribute";
+  }
+  if (const PossiblyExactOperator *Op =
+          dyn_cast<PossiblyExactOperator>(Inst)) {
+    if (Op->isExact())
+      return "has \"exact\" attribute";
+  }
+
   // Allow the instruction.
   return NULL;
 }
diff --git a/lib/Transforms/NaCl/StripAttributes.cpp b/lib/Transforms/NaCl/StripAttributes.cpp
index 476c500756..8074353472 100644
--- a/lib/Transforms/NaCl/StripAttributes.cpp
+++ b/lib/Transforms/NaCl/StripAttributes.cpp
@@ -22,6 +22,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/IR/Function.h"
+#include "llvm/IR/Operator.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/CallSite.h"
 #include "llvm/Transforms/NaCl.h"
@@ -144,6 +145,13 @@ bool StripAttributes::runOnFunction(Function &Func) {
         CheckAttributes(Call.getAttributes());
         Call.setAttributes(AttributeSet());
         Call.setCallingConv(CallingConv::C);
+      } else if (OverflowingBinaryOperator *Op =
+                     dyn_cast<OverflowingBinaryOperator>(Inst)) {
+        cast<BinaryOperator>(Op)->setHasNoUnsignedWrap(false);
+        cast<BinaryOperator>(Op)->setHasNoSignedWrap(false);
+      } else if (PossiblyExactOperator *Op =
+                     dyn_cast<PossiblyExactOperator>(Inst)) {
+        cast<BinaryOperator>(Op)->setIsExact(false);
       }
     }
   }
diff --git a/test/NaCl/PNaClABI/abi-arithmetic-attributes.ll b/test/NaCl/PNaClABI/abi-arithmetic-attributes.ll
new file mode 100644
index 0000000000..03304fb08c
--- /dev/null
+++ b/test/NaCl/PNaClABI/abi-arithmetic-attributes.ll
@@ -0,0 +1,35 @@
+; RUN: pnacl-abicheck < %s | FileCheck %s
+
+; This tests that the arithmetic attributes "nuw" and "nsw" ("no
+; unsigned wrap" and "no signed wrap") and "exact" are disallowed by
+; the PNaCl ABI verifier.
+
+define void @allowed_cases() {
+  %add = add i32 1, 2
+  %shl = shl i32 3, 4
+  %udiv = udiv i32 4, 2
+  %lshr = lshr i32 2, 1
+  %ashr = ashr i32 2, 1
+  ret void
+}
+; CHECK-NOT: disallowed
+
+
+define void @rejected_cases() {
+  %add = add nsw i32 1, 2
+; CHECK: disallowed: has "nsw" attribute: %add
+  %shl1 = shl nuw i32 3, 4
+; CHECK-NEXT: disallowed: has "nuw" attribute: %shl1
+  %sub = sub nsw nuw i32 5, 6
+; CHECK-NEXT: disallowed: has "nuw" attribute: %sub
+
+  %lshr = lshr exact i32 2, 1
+; CHECK-NEXT: disallowed: has "exact" attribute: %lshr
+  %ashr = ashr exact i32 2, 1
+; CHECK-NEXT: disallowed: has "exact" attribute: %ashr
+  %udiv = udiv exact i32 4, 2
+; CHECK-NEXT: disallowed: has "exact" attribute: %udiv
+
+  ret void
+}
+; CHECK-NOT: disallowed
diff --git a/test/Transforms/NaCl/strip-attributes.ll b/test/Transforms/NaCl/strip-attributes.ll
index fda8c30f6b..d4d580be81 100644
--- a/test/Transforms/NaCl/strip-attributes.ll
+++ b/test/Transforms/NaCl/strip-attributes.ll
@@ -18,3 +18,14 @@ define void @call_attrs() {
 ; rid of them here.
 declare i8* @llvm.nacl.read.tp()
 ; CHECK: declare i8* @llvm.nacl.read.tp() #{{[0-9]+}}
+
+define void @arithmetic_attrs() {
+  %add = add nsw i32 1, 2
+  %shl = shl nuw i32 3, 4
+  %lshr = lshr exact i32 2, 1
+  ret void
+}
+; CHECK: define void @arithmetic_attrs() {
+; CHECK-NEXT: %add = add i32 1, 2
+; CHECK-NEXT: %shl = shl i32 3, 4
+; CHECK-NEXT: %lshr = lshr i32 2, 1