From b0d7be6eb6b7a0d33687b5ca37ea7a67b5032824 Mon Sep 17 00:00:00 2001 From: Bob Wilson Date: Sat, 20 Mar 2010 22:20:40 +0000 Subject: pr6652: Use LDM to restore PC to the return address on ARMv4. Patch by John Tytgat! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99096 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/ARM/ARMLoadStoreOptimizer.cpp | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'lib/Target/ARM/ARMLoadStoreOptimizer.cpp') diff --git a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp index d0a3179..bdbec30 100644 --- a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp +++ b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp @@ -1155,19 +1155,24 @@ namespace { }; } -/// MergeReturnIntoLDM - If this is a exit BB, try merging the return op -/// (bx lr) into the preceeding stack restore so it directly restore the value -/// of LR into pc. -/// ldmfd sp!, {r7, lr} +/// MergeReturnIntoLDM - If this is a exit BB, try merging the return ops +/// ("bx lr" and "mov pc, lr") into the preceeding stack restore so it +/// directly restore the value of LR into pc. +/// ldmfd sp!, {..., lr} /// bx lr +/// or +/// ldmfd sp!, {..., lr} +/// mov pc, lr /// => -/// ldmfd sp!, {r7, pc} +/// ldmfd sp!, {..., pc} bool ARMLoadStoreOpt::MergeReturnIntoLDM(MachineBasicBlock &MBB) { if (MBB.empty()) return false; MachineBasicBlock::iterator MBBI = prior(MBB.end()); if (MBBI != MBB.begin() && - (MBBI->getOpcode() == ARM::BX_RET || MBBI->getOpcode() == ARM::tBX_RET)) { + (MBBI->getOpcode() == ARM::BX_RET || + MBBI->getOpcode() == ARM::tBX_RET || + MBBI->getOpcode() == ARM::MOVPCLR)) { MachineInstr *PrevMI = prior(MBBI); if (PrevMI->getOpcode() == ARM::LDM_UPD || PrevMI->getOpcode() == ARM::t2LDM_UPD) { -- cgit v1.1