From 34923bcdbacdce7500ceef304b130ea6bb411be0 Mon Sep 17 00:00:00 2001 From: Evan Cheng Date: Thu, 12 Aug 2010 20:30:05 +0000 Subject: Make sure ARM constant island pass does not break up an IT block. If the split point is in the middle of an IT block, it should move it up to just above the IT instruction. rdar://8302637 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110947 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/ARM/ARMConstantIslandPass.cpp | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) (limited to 'lib/Target/ARM') diff --git a/lib/Target/ARM/ARMConstantIslandPass.cpp b/lib/Target/ARM/ARMConstantIslandPass.cpp index 224842d..9f4de8c 100644 --- a/lib/Target/ARM/ARMConstantIslandPass.cpp +++ b/lib/Target/ARM/ARMConstantIslandPass.cpp @@ -18,6 +18,7 @@ #include "ARMAddressingModes.h" #include "ARMMachineFunctionInfo.h" #include "ARMInstrInfo.h" +#include "Thumb2InstrInfo.h" #include "llvm/CodeGen/MachineConstantPool.h" #include "llvm/CodeGen/MachineFunctionPass.h" #include "llvm/CodeGen/MachineInstrBuilder.h" @@ -1181,11 +1182,13 @@ void ARMConstantIslands::CreateNewWater(unsigned CPUserIndex, MachineBasicBlock::iterator MI = UserMI; ++MI; unsigned CPUIndex = CPUserIndex+1; + unsigned NumCPUsers = CPUsers.size(); + MachineInstr *LastIT = 0; for (unsigned Offset = UserOffset+TII->GetInstSizeInBytes(UserMI); Offset < BaseInsertOffset; Offset += TII->GetInstSizeInBytes(MI), - MI = llvm::next(MI)) { - if (CPUIndex < CPUsers.size() && CPUsers[CPUIndex].MI == MI) { + MI = llvm::next(MI)) { + if (CPUIndex < NumCPUsers && CPUsers[CPUIndex].MI == MI) { CPUser &U = CPUsers[CPUIndex]; if (!OffsetIsInRange(Offset, EndInsertOffset, U.MaxDisp, U.NegOk, U.IsSoImm)) { @@ -1197,9 +1200,23 @@ void ARMConstantIslands::CreateNewWater(unsigned CPUserIndex, EndInsertOffset += CPUsers[CPUIndex].CPEMI->getOperand(2).getImm(); CPUIndex++; } + + // Remember the last IT instruction. + if (MI->getOpcode() == ARM::t2IT) + LastIT = MI; } + DEBUG(errs() << "Split in middle of big block\n"); - NewMBB = SplitBlockBeforeInstr(prior(MI)); + --MI; + + // Avoid splitting an IT block. + if (LastIT) { + unsigned PredReg = 0; + ARMCC::CondCodes CC = llvm::getITInstrPredicate(MI, PredReg); + if (CC != ARMCC::AL) + MI = LastIT; + } + NewMBB = SplitBlockBeforeInstr(MI); } } -- cgit v1.1