From cfadf3f62230505c1156e07f46c06813271bb5ac Mon Sep 17 00:00:00 2001 From: Shilei Tian Date: Thu, 4 Apr 2024 20:29:26 -0400 Subject: [TableGen] Fix a potential crash when operand doesn't appear in the instruction pattern (#87663) We have a check of whether an operand is in the instruction pattern, and emit an error if it is not, but we simply continue execution, including directly dereferencing a point-like object `InVal`, which will be just created when accessing the map. It contains a `nullptr` so dereferencing it causes crash. This is a very trivial fix. --- llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'llvm') diff --git a/llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp b/llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp index 076d042..7a5d2be 100644 --- a/llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp +++ b/llvm/utils/TableGen/Common/CodeGenDAGPatterns.cpp @@ -3858,8 +3858,10 @@ void CodeGenDAGPatterns::parseInstructionPattern(CodeGenInstruction &CGI, for (unsigned i = NumResults, e = CGI.Operands.size(); i != e; ++i) { CGIOperandList::OperandInfo &Op = CGI.Operands[i]; const std::string &OpName = Op.Name; - if (OpName.empty()) + if (OpName.empty()) { I.error("Operand #" + Twine(i) + " in operands list has no name!"); + continue; + } if (!InstInputs.count(OpName)) { // If this is an operand with a DefaultOps set filled in, we can ignore @@ -3872,16 +3874,19 @@ void CodeGenDAGPatterns::parseInstructionPattern(CodeGenInstruction &CGI, } I.error("Operand $" + OpName + " does not appear in the instruction pattern"); + continue; } TreePatternNodePtr InVal = InstInputs[OpName]; InstInputs.erase(OpName); // It occurred, remove from map. if (InVal->isLeaf() && isa(InVal->getLeafValue())) { Record *InRec = cast(InVal->getLeafValue())->getDef(); - if (!checkOperandClass(Op, InRec)) + if (!checkOperandClass(Op, InRec)) { I.error("Operand $" + OpName + "'s register class disagrees" " between the operand and pattern"); + continue; + } } Operands.push_back(Op.Rec); -- cgit v1.1