[IR] Add Instruction::isLifetimeStartOrEnd, NFC

Instruction::isLifetimeStartOrEnd() checks whether an Instruction is an
llvm.lifetime.start or an llvm.lifetime.end intrinsic.

This was suggested as a cleanup in D55967.

Differential Revision: https://reviews.llvm.org/D56019

llvm-svn: 349964

1 files changed, 2 insertions, 3 deletions

diff --git a/llvm/lib/CodeGen/SafeStackColoring.cpp b/llvm/lib/CodeGen/SafeStackColoring.cpp
index b1914b5d380..726c3800281 100644
--- a/llvm/lib/CodeGen/SafeStackColoring.cpp
+++ b/llvm/lib/CodeGen/SafeStackColoring.cpp
@@ -46,11 +46,10 @@ const StackColoring::LiveRange &StackColoring::getLiveRange(AllocaInst *AI) {
 }
 
 bool StackColoring::readMarker(Instruction *I, bool *IsStart) {
-  auto *II = dyn_cast<IntrinsicInst>(I);
-  if (!II || (II->getIntrinsicID() != Intrinsic::lifetime_start &&
-              II->getIntrinsicID() != Intrinsic::lifetime_end))
+  if (!I->isLifetimeStartOrEnd())
     return false;
 
+  auto *II = cast<IntrinsicInst>(I);
   *IsStart = II->getIntrinsicID() == Intrinsic::lifetime_start;
   return true;
 }