CodeGen: Use MachineInstr& in TargetInstrInfo, NFC

This is mostly a mechanical change to make TargetInstrInfo API take
MachineInstr& (instead of MachineInstr* or MachineBasicBlock::iterator)
when the argument is expected to be a valid MachineInstr.  This is a
general API improvement.

Although it would be possible to do this one function at a time, that
would demand a quadratic amount of churn since many of these functions
call each other.  Instead I've done everything as a block and just
updated what was necessary.

This is mostly mechanical fixes: adding and removing `*` and `&`
operators.  The only non-mechanical change is to split
ARMBaseInstrInfo::getOperandLatencyImpl out from
ARMBaseInstrInfo::getOperandLatency.  Previously, the latter took a
`MachineInstr*` which it updated to the instruction bundle leader; now,
the latter calls the former either with the same `MachineInstr&` or the
bundle leader.

As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.

Note: I updated WebAssembly, Lanai, and AVR (despite being
off-by-default) since it turned out to be easy.  I couldn't run tests
for AVR since llc doesn't link with it turned on.

llvm-svn: 274189

2 files changed, 18 insertions, 21 deletions

diff --git a/llvm/lib/Target/XCore/XCoreInstrInfo.cpp b/llvm/lib/Target/XCore/XCoreInstrInfo.cpp
index 19b74632609..230d470eda2 100644
--- a/llvm/lib/Target/XCore/XCoreInstrInfo.cpp
+++ b/llvm/lib/Target/XCore/XCoreInstrInfo.cpp
@@ -60,17 +60,16 @@ static bool isZeroImm(const MachineOperand &op) {
 /// the destination along with the FrameIndex of the loaded stack slot.  If
 /// not, return 0.  This predicate must return 0 if the instruction has
 /// any side effects other than loading from the stack slot.
-unsigned
-XCoreInstrInfo::isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const{
-  int Opcode = MI->getOpcode();
+unsigned XCoreInstrInfo::isLoadFromStackSlot(const MachineInstr &MI,
+                                             int &FrameIndex) const {
+  int Opcode = MI.getOpcode();
   if (Opcode == XCore::LDWFI) 
   {
-    if ((MI->getOperand(1).isFI()) && // is a stack slot
-        (MI->getOperand(2).isImm()) &&  // the imm is zero
-        (isZeroImm(MI->getOperand(2)))) 
-    {
-      FrameIndex = MI->getOperand(1).getIndex();
-      return MI->getOperand(0).getReg();
+    if ((MI.getOperand(1).isFI()) &&  // is a stack slot
+        (MI.getOperand(2).isImm()) && // the imm is zero
+        (isZeroImm(MI.getOperand(2)))) {
+      FrameIndex = MI.getOperand(1).getIndex();
+      return MI.getOperand(0).getReg();
     }
   }
   return 0;
@@ -81,18 +80,16 @@ XCoreInstrInfo::isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) con
   /// the source reg along with the FrameIndex of the loaded stack slot.  If
   /// not, return 0.  This predicate must return 0 if the instruction has
   /// any side effects other than storing to the stack slot.
-unsigned
-XCoreInstrInfo::isStoreToStackSlot(const MachineInstr *MI,
-                                   int &FrameIndex) const {
-  int Opcode = MI->getOpcode();
+unsigned XCoreInstrInfo::isStoreToStackSlot(const MachineInstr &MI,
+                                            int &FrameIndex) const {
+  int Opcode = MI.getOpcode();
   if (Opcode == XCore::STWFI)
   {
-    if ((MI->getOperand(1).isFI()) && // is a stack slot
-        (MI->getOperand(2).isImm()) &&  // the imm is zero
-        (isZeroImm(MI->getOperand(2))))
-    {
-      FrameIndex = MI->getOperand(1).getIndex();
-      return MI->getOperand(0).getReg();
+    if ((MI.getOperand(1).isFI()) &&  // is a stack slot
+        (MI.getOperand(2).isImm()) && // the imm is zero
+        (isZeroImm(MI.getOperand(2)))) {
+      FrameIndex = MI.getOperand(1).getIndex();
+      return MI.getOperand(0).getReg();
     }
   }
   return 0;
diff --git a/llvm/lib/Target/XCore/XCoreInstrInfo.h b/llvm/lib/Target/XCore/XCoreInstrInfo.h
index 69e75c586fe..d9b4937a688 100644
--- a/llvm/lib/Target/XCore/XCoreInstrInfo.h
+++ b/llvm/lib/Target/XCore/XCoreInstrInfo.h
@@ -39,7 +39,7 @@ public:
   /// the destination along with the FrameIndex of the loaded stack slot.  If
   /// not, return 0.  This predicate must return 0 if the instruction has
   /// any side effects other than loading from the stack slot.
-  unsigned isLoadFromStackSlot(const MachineInstr *MI,
+  unsigned isLoadFromStackSlot(const MachineInstr &MI,
                                int &FrameIndex) const override;
 
   /// isStoreToStackSlot - If the specified machine instruction is a direct
@@ -47,7 +47,7 @@ public:
   /// the source reg along with the FrameIndex of the loaded stack slot.  If
   /// not, return 0.  This predicate must return 0 if the instruction has
   /// any side effects other than storing to the stack slot.
-  unsigned isStoreToStackSlot(const MachineInstr *MI,
+  unsigned isStoreToStackSlot(const MachineInstr &MI,
                               int &FrameIndex) const override;
 
   bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,