From 84be3d5a73313eb19f2f9e0512153cd2e6f46c54 Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Sat, 5 Jan 2013 05:05:51 +0000 Subject: Don't call destructors on MachineInstr and MachineOperand. The series of patches leading up to this one makes llc -O0 run 8% faster. When deallocating a MachineFunction, there is no need to visit all MachineInstr and MachineOperand objects to deallocate them. All their memory come from a BumpPtrAllocator that is about to be purged, and they have empty destructors anyway. This only applies when deallocating the MachineFunction. DeleteMachineInstr() should still be used to recycle MI memory during the codegen passes. Remove the LeakDetector support for MachineInstr. I've never seen it used before, and now it definitely doesn't work. With this patch, leaked MachineInstrs would be much less of a problem since all of their memory will be reclaimed by ~MachineFunction(). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171599 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/MachineFunction.cpp | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'lib/CodeGen/MachineFunction.cpp') diff --git a/lib/CodeGen/MachineFunction.cpp b/lib/CodeGen/MachineFunction.cpp index 08d116afea..9647e83e24 100644 --- a/lib/CodeGen/MachineFunction.cpp +++ b/lib/CodeGen/MachineFunction.cpp @@ -76,7 +76,13 @@ MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM, } MachineFunction::~MachineFunction() { - BasicBlocks.clear(); + // Don't call destructors on MachineInstr and MachineOperand. All of their + // memory comes from the BumpPtrAllocator which is about to be purged. + // + // Do call MachineBasicBlock destructors, it contains std::vectors. + for (iterator I = begin(), E = end(); I != E; I = BasicBlocks.erase(I)) + I->Insts.clearAndLeakNodesUnsafely(); + InstructionRecycler.clear(Allocator); OperandRecycler.clear(Allocator); BasicBlockRecycler.clear(Allocator); @@ -176,15 +182,17 @@ MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { /// DeleteMachineInstr - Delete the given MachineInstr. /// +/// This function also serves as the MachineInstr destructor - the real +/// ~MachineInstr() destructor must be empty. void MachineFunction::DeleteMachineInstr(MachineInstr *MI) { // Strip it for parts. The operand array and the MI object itself are // independently recyclable. if (MI->Operands) deallocateOperandArray(MI->CapOperands, MI->Operands); - MI->Operands = 0; - MI->NumOperands = 0; - MI->~MachineInstr(); + // Don't call ~MachineInstr() which must be trivial anyway because + // ~MachineFunction drops whole lists of MachineInstrs wihout calling their + // destructors. InstructionRecycler.Deallocate(Allocator, MI); } -- cgit v1.2.3