[ValueTracking] Extend range metadata to call/invoke

Summary:
With this patch, range metadata can be added to call/invoke including
IntrinsicInst. Previously, it could only be added to load.

Rename computeKnownBitsLoad to computeKnownBitsFromRangeMetadata because
range metadata is not only used by load.

Update the language reference to reflect this change.

Test Plan:
Add several tests in range-2.ll to confirm the verifier is happy with
having range metadata on call/invoke.

Add two tests in AddOverFlow.ll to confirm annotating range metadata to
call/invoke can benefit InstCombine.

Reviewers: meheff, nlewycky, reames, hfinkel, eliben

Reviewed By: eliben

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4187

llvm-svn: 211281

1 files changed, 2 insertions, 1 deletions

diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index d1c7f7d25c3..ad3c29c564e 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -2233,7 +2233,8 @@ void Verifier::visitInstruction(Instruction &I) {
   }
 
   MDNode *MD = I.getMetadata(LLVMContext::MD_range);
-  Assert1(!MD || isa<LoadInst>(I), "Ranges are only for loads!", &I);
+  Assert1(!MD || isa<LoadInst>(I) || isa<CallInst>(I) || isa<InvokeInst>(I),
+          "Ranges are only for loads, calls and invokes!", &I);
 
   InstsInThisBlock.insert(&I);
 }