[PATCH] D157948: [NFC]Fix possibly deref nullptr

[Wang, Xin via Phabricator via llvm-commits]

XinWang10 created this revision.
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XinWang10 requested review of this revision.
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1. In X86LowerAMXType.cpp dyn_cast could lead to UserI be nullptr which coud be dref in IRBuilder constructor.
2. In AsmPrinter.cpp, doInitialization could make MMI be nullptr if MMIWP->getMMI() is false, then the deref after could be unexpected.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D157948

Files:
  llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
  llvm/lib/Target/X86/X86LowerAMXType.cpp


Index: llvm/lib/Target/X86/X86LowerAMXType.cpp
===================================================================
--- llvm/lib/Target/X86/X86LowerAMXType.cpp
+++ llvm/lib/Target/X86/X86LowerAMXType.cpp
@@ -494,7 +494,7 @@
   Value *Row = II->getOperand(0);
   Value *Col = II->getOperand(1);
 
-  Instruction *UserI = dyn_cast<Instruction>(U.getUser());
+  Instruction *UserI = cast<Instruction>(U.getUser());
   IRBuilder<> Builder(UserI);
   Value *Stride = Builder.getInt64(64);
   std::array<Value *, 4> Args = {Row, Col, Ptr, Stride};
Index: llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
===================================================================
--- llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -516,7 +516,7 @@
                             CodeViewLineTablesGroupDescription);
     }
     if (!EmitCodeView || M.getDwarfVersion()) {
-      if (MMI->hasDebugInfo()) {
+      if (MMI && MMI->hasDebugInfo()) {
         DD = new DwarfDebug(this);
         Handlers.emplace_back(std::unique_ptr<DwarfDebug>(DD), DbgTimerName,
                               DbgTimerDescription, DWARFGroupName,
@@ -573,7 +573,8 @@
       break;
     case WinEH::EncodingType::X86:
     case WinEH::EncodingType::Itanium:
-      ES = new WinException(this);
+      if (MMI)
+        ES = new WinException(this);
       break;
     }
     break;


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