[llvm] r356566 - [CGP] convert chain of 'if' to 'switch'; NFC

[Sanjay Patel via llvm-commits]

Author: spatel
Date: Wed Mar 20 08:53:06 2019
New Revision: 356566

URL: http://llvm.org/viewvc/llvm-project?rev=356566&view=rev
Log:
[CGP] convert chain of 'if' to 'switch'; NFC

This should be extended, but CGP does some strange things,
so I'm intentionally not changing the potential order of
any transforms yet.

Modified:
    llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp

Modified: llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp?rev=356566&r1=356565&r2=356566&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp (original)
+++ llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp Wed Mar 20 08:53:06 2019
@@ -6876,6 +6876,7 @@ bool CodeGenPrepare::optimizeInst(Instru
   if (InsertedInsts.count(I))
     return false;
 
+  // TODO: Move into the switch on opcode below here.
   if (PHINode *P = dyn_cast<PHINode>(I)) {
     // It is possible for very late stage optimizations (such as SimplifyCFG)
     // to introduce PHI nodes too late to be cleaned up.  If we detect such a
@@ -6994,20 +6995,18 @@ bool CodeGenPrepare::optimizeInst(Instru
   if (tryToSinkFreeOperands(I))
     return true;
 
-  if (CallInst *CI = dyn_cast<CallInst>(I))
-    return optimizeCallInst(CI, ModifiedDT);
-
-  if (SelectInst *SI = dyn_cast<SelectInst>(I))
-    return optimizeSelectInst(SI, ModifiedDT);
-
-  if (ShuffleVectorInst *SVI = dyn_cast<ShuffleVectorInst>(I))
-    return optimizeShuffleVectorInst(SVI);
-
-  if (auto *Switch = dyn_cast<SwitchInst>(I))
-    return optimizeSwitchInst(Switch);
-
-  if (isa<ExtractElementInst>(I))
-    return optimizeExtractElementInst(I);
+  switch (I->getOpcode()) {
+  case Instruction::Call:
+    return optimizeCallInst(cast<CallInst>(I), ModifiedDT);
+  case Instruction::Select:
+    return optimizeSelectInst(cast<SelectInst>(I), ModifiedDT);
+  case Instruction::ShuffleVector:
+    return optimizeShuffleVectorInst(cast<ShuffleVectorInst>(I));
+  case Instruction::Switch:
+    return optimizeSwitchInst(cast<SwitchInst>(I));
+  case Instruction::ExtractElement:
+    return optimizeExtractElementInst(cast<ExtractElementInst>(I));
+  }
 
   return false;
 }