diff options
Diffstat (limited to 'lib/CodeGen/VirtRegRewriter.cpp')
| -rw-r--r-- | lib/CodeGen/VirtRegRewriter.cpp | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/lib/CodeGen/VirtRegRewriter.cpp b/lib/CodeGen/VirtRegRewriter.cpp index be0b016..48558fe 100644 --- a/lib/CodeGen/VirtRegRewriter.cpp +++ b/lib/CodeGen/VirtRegRewriter.cpp @@ -1157,6 +1157,32 @@ private: return false; } + /// CommuteChangesDestination - We are looking for r0 = op r1, r2 and + /// where SrcReg is r1 and it is tied to r0. Return true if after + /// commuting this instruction it will be r0 = op r2, r1. + static bool CommuteChangesDestination(MachineInstr *DefMI, + const TargetInstrDesc &TID, + unsigned SrcReg, + const TargetInstrInfo *TII, + unsigned &DstIdx) { + if (TID.getNumDefs() != 1 && TID.getNumOperands() != 3) + return false; + if (!DefMI->getOperand(1).isReg() || + DefMI->getOperand(1).getReg() != SrcReg) + return false; + unsigned DefIdx; + if (!DefMI->isRegTiedToDefOperand(1, &DefIdx) || DefIdx != 0) + return false; + unsigned SrcIdx1, SrcIdx2; + if (!TII->findCommutedOpIndices(DefMI, SrcIdx1, SrcIdx2)) + return false; + if (SrcIdx1 == 1 && SrcIdx2 == 2) { + DstIdx = 2; + return true; + } + return false; + } + /// CommuteToFoldReload - /// Look for /// r1 = load fi#1 @@ -1185,7 +1211,7 @@ private: unsigned NewDstIdx; if (DefMII != MBB.begin() && TID.isCommutable() && - TII->CommuteChangesDestination(DefMI, NewDstIdx)) { + CommuteChangesDestination(DefMI, TID, SrcReg, TII, NewDstIdx)) { MachineOperand &NewDstMO = DefMI->getOperand(NewDstIdx); unsigned NewReg = NewDstMO.getReg(); if (!NewDstMO.isKill() || TRI->regsOverlap(NewReg, SrcReg)) |