[NFC] Unify guards detection

We have multiple places in code where we try to identify whether or not
some instruction is a guard. This patch factors out this logic into a separate
utility function which works uniformly in all places.

Differential Revision: https://reviews.llvm.org/D51152
Reviewed By: fedor.sergeev

llvm-svn: 340921

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Utils/GuardUtils.cpp b/llvm/lib/Transforms/Utils/GuardUtils.cpp
index 08de0a4..5a9a9df 100644
--- a/llvm/lib/Transforms/Utils/GuardUtils.cpp
+++ b/llvm/lib/Transforms/Utils/GuardUtils.cpp
@@ -15,6 +15,7 @@
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/PatternMatch.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 
 using namespace llvm;
@@ -24,6 +25,11 @@ static cl::opt<uint32_t> PredicatePassBranchWeight(
     cl::desc("The probability of a guard failing is assumed to be the "
              "reciprocal of this value (default = 1 << 20)"));
 
+bool llvm::isGuard(const User *U) {
+  using namespace llvm::PatternMatch;
+  return match(U, m_Intrinsic<Intrinsic::experimental_guard>());
+}
+
 void llvm::makeGuardControlFlowExplicit(Function *DeoptIntrinsic,
                                         CallInst *Guard) {
   OperandBundleDef DeoptOB(*Guard->getOperandBundle(LLVMContext::OB_deopt));