diff options
Diffstat (limited to 'llvm/lib/CodeGen/MachineLICM.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/MachineLICM.cpp | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/llvm/lib/CodeGen/MachineLICM.cpp b/llvm/lib/CodeGen/MachineLICM.cpp index 1a8e92332bc..a8368e9c80d 100644 --- a/llvm/lib/CodeGen/MachineLICM.cpp +++ b/llvm/lib/CodeGen/MachineLICM.cpp @@ -330,6 +330,10 @@ bool MachineLICM::runOnMachineFunction(MachineFunction &MF) { /// Return true if instruction stores to the specified frame. static bool InstructionStoresToFI(const MachineInstr *MI, int FI) { + // If we lost memory operands, conservatively assume that the instruction + // writes to all slots. + if (MI->memoperands_empty()) + return true; for (MachineInstr::mmo_iterator o = MI->memoperands_begin(), oe = MI->memoperands_end(); o != oe; ++o) { if (!(*o)->isStore() || !(*o)->getPseudoValue()) @@ -846,8 +850,14 @@ MachineLICM::calcRegisterCost(const MachineInstr *MI, bool ConsiderSeen, /// Return true if this machine instruction loads from global offset table or /// constant pool. -static bool isLoadFromGOTOrConstantPool(MachineInstr &MI) { +static bool mayLoadFromGOTOrConstantPool(MachineInstr &MI) { assert (MI.mayLoad() && "Expected MI that loads!"); + + // If we lost memory operands, conservatively assume that the instruction + // reads from everything.. + if (MI.memoperands_empty()) + return true; + for (MachineInstr::mmo_iterator I = MI.memoperands_begin(), E = MI.memoperands_end(); I != E; ++I) { if (const PseudoSourceValue *PSV = (*I)->getPseudoValue()) { @@ -872,7 +882,7 @@ bool MachineLICM::IsLICMCandidate(MachineInstr &I) { // from constant memory are not safe to speculate all the time, for example // indexed load from a jump table. // Stores and side effects are already checked by isSafeToMove. - if (I.mayLoad() && !isLoadFromGOTOrConstantPool(I) && + if (I.mayLoad() && !mayLoadFromGOTOrConstantPool(I) && !IsGuaranteedToExecute(I.getParent())) return false; |
