From ff03048c1350fcc4fda1ef6d6c57252f3a950854 Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Thu, 28 Jul 2011 21:48:00 +0000 Subject: LangRef and basic memory-representation/reading/writing for 'cmpxchg' and 'atomicrmw' instructions, which allow representing all the current atomic rmw intrinsics. The allowed operands for these instructions are heavily restricted at the moment; we can probably loosen it a bit, but supporting general first-class types (where it makes sense) might get a bit complicated, given how SelectionDAG works. As an initial cut, these operations do not support specifying an alignment, but it would be possible to add if we think it's useful. Specifying an alignment lower than the natural alignment would be essentially impossible to support on anything other than x86, but specifying a greater alignment would be possible. I can't think of any useful optimizations which would use that information, but maybe someone else has ideas. Optimizer/codegen support coming soon. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136404 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Bitcode/Reader/BitcodeReader.cpp | 59 ++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) (limited to 'lib/Bitcode/Reader/BitcodeReader.cpp') diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp index bab33ed257..e0af683a24 100644 --- a/lib/Bitcode/Reader/BitcodeReader.cpp +++ b/lib/Bitcode/Reader/BitcodeReader.cpp @@ -131,6 +131,23 @@ static int GetDecodedBinaryOpcode(unsigned Val, Type *Ty) { } } +static AtomicRMWInst::BinOp GetDecodedRMWOperation(unsigned Val) { + switch (Val) { + default: return AtomicRMWInst::BAD_BINOP; + case bitc::RMW_XCHG: return AtomicRMWInst::Xchg; + case bitc::RMW_ADD: return AtomicRMWInst::Add; + case bitc::RMW_SUB: return AtomicRMWInst::Sub; + case bitc::RMW_AND: return AtomicRMWInst::And; + case bitc::RMW_NAND: return AtomicRMWInst::Nand; + case bitc::RMW_OR: return AtomicRMWInst::Or; + case bitc::RMW_XOR: return AtomicRMWInst::Xor; + case bitc::RMW_MAX: return AtomicRMWInst::Max; + case bitc::RMW_MIN: return AtomicRMWInst::Min; + case bitc::RMW_UMAX: return AtomicRMWInst::UMax; + case bitc::RMW_UMIN: return AtomicRMWInst::UMin; + } +} + static AtomicOrdering GetDecodedOrdering(unsigned Val) { switch (Val) { case bitc::ORDERING_NOTATOMIC: return NotAtomic; @@ -2595,6 +2612,48 @@ bool BitcodeReader::ParseFunctionBody(Function *F) { InstructionList.push_back(I); break; } + case bitc::FUNC_CODE_INST_CMPXCHG: { + // CMPXCHG:[ptrty, ptr, cmp, new, vol, ordering, synchscope] + unsigned OpNum = 0; + Value *Ptr, *Cmp, *New; + if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) || + getValue(Record, OpNum, + cast(Ptr->getType())->getElementType(), Cmp) || + getValue(Record, OpNum, + cast(Ptr->getType())->getElementType(), New) || + OpNum+3 != Record.size()) + return Error("Invalid CMPXCHG record"); + AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+1]); + if (Ordering == NotAtomic) + return Error("Invalid CMPXCHG record"); + SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+2]); + I = new AtomicCmpXchgInst(Ptr, Cmp, New, Ordering, SynchScope); + cast(I)->setVolatile(Record[OpNum]); + InstructionList.push_back(I); + break; + } + case bitc::FUNC_CODE_INST_ATOMICRMW: { + // ATOMICRMW:[ptrty, ptr, val, op, vol, ordering, synchscope] + unsigned OpNum = 0; + Value *Ptr, *Val; + if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) || + getValue(Record, OpNum, + cast(Ptr->getType())->getElementType(), Val) || + OpNum+4 != Record.size()) + return Error("Invalid ATOMICRMW record"); + AtomicRMWInst::BinOp Operation = GetDecodedRMWOperation(Record[OpNum]); + if (Operation < AtomicRMWInst::FIRST_BINOP || + Operation > AtomicRMWInst::LAST_BINOP) + return Error("Invalid ATOMICRMW record"); + AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]); + if (Ordering == NotAtomic) + return Error("Invalid ATOMICRMW record"); + SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]); + I = new AtomicRMWInst(Operation, Ptr, Val, Ordering, SynchScope); + cast(I)->setVolatile(Record[OpNum+1]); + InstructionList.push_back(I); + break; + } case bitc::FUNC_CODE_INST_FENCE: { // FENCE:[ordering, synchscope] if (2 != Record.size()) return Error("Invalid FENCE record"); -- cgit v1.2.3-18-g5258