[llvm] r306279 - [IfConversion] Hoist removeBranch calls out of if/else clauses [NFC]

[Mikael Holmen via llvm-commits]

Author: uabelho
Date: Mon Jun 26 02:33:04 2017
New Revision: 306279

URL: http://llvm.org/viewvc/llvm-project?rev=306279&view=rev
Log:
[IfConversion] Hoist removeBranch calls out of if/else clauses [NFC]

Summary:
Also added a comment.

Pulled out of https://reviews.llvm.org/D34099.

Reviewers: iteratee

Reviewed By: iteratee

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34388

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

Modified: llvm/trunk/lib/CodeGen/IfConversion.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/IfConversion.cpp?rev=306279&r1=306278&r2=306279&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/IfConversion.cpp (original)
+++ llvm/trunk/lib/CodeGen/IfConversion.cpp Mon Jun 26 02:33:04 2017
@@ -1474,8 +1474,11 @@ bool IfConverter::IfConvertSimple(BBInfo
     DontKill.addLiveIns(NextMBB);
   }
 
+  // Remove the branches from the entry so we can add the contents of the true
+  // block to it.
+  BBI.NonPredSize -= TII->removeBranch(*BBI.BB);
+
   if (CvtMBB.pred_size() > 1) {
-    BBI.NonPredSize -= TII->removeBranch(*BBI.BB);
     // Copy instructions in the true block, predicate them, and add them to
     // the entry block.
     CopyAndPredicateBlock(BBI, *CvtBBI, Cond);
@@ -1484,11 +1487,11 @@ bool IfConverter::IfConvertSimple(BBInfo
     // explicitly remove CvtBBI as a successor.
     BBI.BB->removeSuccessor(&CvtMBB, true);
   } else {
+    // Predicate the instructions in the true block.
     RemoveKills(CvtMBB.begin(), CvtMBB.end(), DontKill, *TRI);
     PredicateBlock(*CvtBBI, CvtMBB.end(), Cond);
 
     // Merge converted block into entry block.
-    BBI.NonPredSize -= TII->removeBranch(*BBI.BB);
     MergeBlocks(BBI, *CvtBBI);
   }
 
@@ -1588,8 +1591,11 @@ bool IfConverter::IfConvertTriangle(BBIn
     BBCvt = MBPI->getEdgeProbability(BBI.BB, &CvtMBB);
   }
 
+  // Remove the branches from the entry so we can add the contents of the true
+  // block to it.
+  BBI.NonPredSize -= TII->removeBranch(*BBI.BB);
+
   if (CvtMBB.pred_size() > 1) {
-    BBI.NonPredSize -= TII->removeBranch(*BBI.BB);
     // Copy instructions in the true block, predicate them, and add them to
     // the entry block.
     CopyAndPredicateBlock(BBI, *CvtBBI, Cond, true);
@@ -1603,7 +1609,6 @@ bool IfConverter::IfConvertTriangle(BBIn
     PredicateBlock(*CvtBBI, CvtMBB.end(), Cond);
 
     // Now merge the entry of the triangle with the true block.
-    BBI.NonPredSize -= TII->removeBranch(*BBI.BB);
     MergeBlocks(BBI, *CvtBBI, false);
   }