1 files changed, 20 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 5a70d8bb640..8987ee0e848 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -1102,6 +1102,26 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
       return EraseInstFromFunction(*II);
     }
 
+    // assume( (load addr) != null ) -> add 'nonnull' metadata to load
+    // (if assume is valid at the load)
+    if (ICmpInst* ICmp = dyn_cast<ICmpInst>(IIOperand)) {
+      Value *LHS = ICmp->getOperand(0);
+      Value *RHS = ICmp->getOperand(1);
+      if (ICmpInst::ICMP_NE == ICmp->getPredicate() &&
+          isa<LoadInst>(LHS) &&
+          isa<Constant>(RHS) &&
+          RHS->getType()->isPointerTy() &&
+          cast<Constant>(RHS)->isNullValue()) {
+        LoadInst* LI = cast<LoadInst>(LHS);
+        if (isValidAssumeForContext(II, LI, DL, DT)) {
+          MDNode* MD = MDNode::get(II->getContext(), ArrayRef<Value*>());
+          LI->setMetadata(LLVMContext::MD_nonnull, MD);
+          return EraseInstFromFunction(*II);
+        }
+      }
+      // TODO: apply nonnull return attributes to calls and invokes
+      // TODO: apply range metadata for range check patterns?
+    }
     // If there is a dominating assume with the same condition as this one,
     // then this one is redundant, and should be removed.
     APInt KnownZero(1, 0), KnownOne(1, 0);