[WebAssembly] Simplify iterator navigations (NFC)

Summary:
- Replaces some uses of `MachineFunction::iterator(MBB)` with
  `MBB->getIterator()` and `MachineBasicBlock::iterator(MI)` with
  `MI->getIterator()`, which are simpler.
- Replaces some uses of `std::prev` of `std::next` that takes a
  MachineFunction or MachineBasicBlock iterator with `getPrevNode` and
  `getNextNode`, which are also simpler.

Reviewers: sbc100

Subscribers: dschuff, sunfish, jgravelle-google, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58913

llvm-svn: 355444

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyExplicitLocals.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyExplicitLocals.cpp
index 8494737d43d..d1bb8a7097a 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyExplicitLocals.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyExplicitLocals.cpp
@@ -274,7 +274,7 @@ bool WebAssemblyExplicitLocals::runOnMachineFunction(MachineFunction &MF) {
         if (!MFI.isVRegStackified(OldReg)) {
           const TargetRegisterClass *RC = MRI.getRegClass(OldReg);
           unsigned NewReg = MRI.createVirtualRegister(RC);
-          auto InsertPt = std::next(MachineBasicBlock::iterator(&MI));
+          auto InsertPt = std::next(MI.getIterator());
           if (MI.getOpcode() == WebAssembly::IMPLICIT_DEF) {
             MI.eraseFromParent();
             Changed = true;