[turbofan] Clean up and factor out branch generation logic.

src/compiler/mips64/instruction-selector-mips64.cc

Index: src/compiler/mips64/instruction-selector-mips64.cc
diff --git a/src/compiler/mips64/instruction-selector-mips64.cc b/src/compiler/mips64/instruction-selector-mips64.cc
index f1a585d0596e1df6044fd6ca106746c9e4aacbc6..80504ed72c3ea0471328eda3c5ed54fbaa1c2b69 100644
--- a/src/compiler/mips64/instruction-selector-mips64.cc
+++ b/src/compiler/mips64/instruction-selector-mips64.cc
@@ -871,12 +871,6 @@ void VisitWordCompareZero(InstructionSelector* selector, Node* user,
 void InstructionSelector::VisitBranch(Node* branch, BasicBlock* tbranch,
                                       BasicBlock* fbranch) {
   FlagsContinuation cont(kNotEqual, tbranch, fbranch);
-  // If we can fall through to the true block, invert the branch.
-  if (IsNextInAssemblyOrder(tbranch)) {
-    cont.Negate();
-    cont.SwapBlocks();
-  }
-
   VisitWordCompareZero(this, branch, branch->InputAt(0), &cont);
 }