[llvm] ef4b9c3 - Fix crash while printing MMO target flags

[Stanislav Mekhanoshin via llvm-commits]

Author: Stanislav Mekhanoshin
Date: 2022-09-14T17:29:48-07:00
New Revision: ef4b9c33f5dd096a4d7cd03654c17492f3802d89

URL: https://github.com/llvm/llvm-project/commit/ef4b9c33f5dd096a4d7cd03654c17492f3802d89
DIFF: https://github.com/llvm/llvm-project/commit/ef4b9c33f5dd096a4d7cd03654c17492f3802d89.diff

LOG: Fix crash while printing MMO target flags

MachineMemOperand::print can dereference a NULL pointer if TII
is not passed from the printMemOperand. This does not happen while
dumping the DAG/MIR from llc but crashes the debugger if a dump()
method is called from gdb.

Differential Revision: https://reviews.llvm.org/D133903

Added: 
    

Modified: 
    llvm/lib/CodeGen/MachineOperand.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/MachineOperand.cpp b/llvm/lib/CodeGen/MachineOperand.cpp
index 393a4f71b3cb2..df52741bc4b92 100644
--- a/llvm/lib/CodeGen/MachineOperand.cpp
+++ b/llvm/lib/CodeGen/MachineOperand.cpp
@@ -1114,15 +1114,24 @@ void MachineMemOperand::print(raw_ostream &OS, ModuleSlotTracker &MST,
     OS << "dereferenceable ";
   if (isInvariant())
     OS << "invariant ";
-  if (getFlags() & MachineMemOperand::MOTargetFlag1)
-    OS << '"' << getTargetMMOFlagName(*TII, MachineMemOperand::MOTargetFlag1)
-       << "\" ";
-  if (getFlags() & MachineMemOperand::MOTargetFlag2)
-    OS << '"' << getTargetMMOFlagName(*TII, MachineMemOperand::MOTargetFlag2)
-       << "\" ";
-  if (getFlags() & MachineMemOperand::MOTargetFlag3)
-    OS << '"' << getTargetMMOFlagName(*TII, MachineMemOperand::MOTargetFlag3)
-       << "\" ";
+  if (TII) {
+    if (getFlags() & MachineMemOperand::MOTargetFlag1)
+      OS << '"' << getTargetMMOFlagName(*TII, MachineMemOperand::MOTargetFlag1)
+         << "\" ";
+    if (getFlags() & MachineMemOperand::MOTargetFlag2)
+      OS << '"' << getTargetMMOFlagName(*TII, MachineMemOperand::MOTargetFlag2)
+         << "\" ";
+    if (getFlags() & MachineMemOperand::MOTargetFlag3)
+      OS << '"' << getTargetMMOFlagName(*TII, MachineMemOperand::MOTargetFlag3)
+         << "\" ";
+  } else {
+    if (getFlags() & MachineMemOperand::MOTargetFlag1)
+      OS << "\"MOTargetFlag1\" ";
+    if (getFlags() & MachineMemOperand::MOTargetFlag2)
+      OS << "\"MOTargetFlag2\" ";
+    if (getFlags() & MachineMemOperand::MOTargetFlag3)
+      OS << "\"MOTargetFlag3\" ";
+  }
 
   assert((isLoad() || isStore()) &&
          "machine memory operand must be a load or store (or both)");