CodeGen: Create a proper ModuleSlotTracker for MachineInstr

Another follow-up related to r240848: try a little harder to share slot
tracking calculations within a single `MachineInstr` dump.  This is
unrelated to `MachineFunction::print()`, since that should be passing
through the function's `ModuleSlotTracker` by now, but could affect the
speed of dumping from a debugger if there is more than one IR-level
operand.

llvm-svn: 240852

1 files changed, 7 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp
index 39a395081db..fdc4226ad92 100644
--- a/llvm/lib/CodeGen/MachineInstr.cpp
+++ b/llvm/lib/CodeGen/MachineInstr.cpp
@@ -1532,8 +1532,13 @@ void MachineInstr::dump() const {
 }
 
 void MachineInstr::print(raw_ostream &OS, bool SkipOpers) const {
-  ModuleSlotTracker DummyMST(nullptr);
-  print(OS, DummyMST, SkipOpers);
+  const Module *M = nullptr;
+  if (const MachineBasicBlock *MBB = getParent())
+    if (const MachineFunction *MF = MBB->getParent())
+      M = MF->getFunction()->getParent();
+
+  ModuleSlotTracker MST(M);
+  print(OS, MST, SkipOpers);
 }
 
 void MachineInstr::print(raw_ostream &OS, ModuleSlotTracker &MST,