From: Jakob Stoklund Olesen Date: Tue, 7 Sep 2010 22:38:45 +0000 (+0000) Subject: Don't add operands during register rewriting. X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6b964cd21118e816a4669d660d2c96751dc7ccf3;p=oota-llvm.git Don't add operands during register rewriting. LiveIntervals already adds operands for super-registers when a subreg def defines the whole register. Thus, it is not necessary to do it again when rewriting. In fact, the super-register imp-defs caused miscompilations because the late scheduler couldn't see that the super-register was read. We still add super-reg operands when rewriting virtuals to physicals. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113299 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/CodeGen/VirtRegRewriter.cpp b/lib/CodeGen/VirtRegRewriter.cpp index d988e106c52..240d28cf301 100644 --- a/lib/CodeGen/VirtRegRewriter.cpp +++ b/lib/CodeGen/VirtRegRewriter.cpp @@ -67,23 +67,16 @@ VirtRegRewriter::~VirtRegRewriter() {} /// Note that operands may be added, so the MO reference is no longer valid. static void substitutePhysReg(MachineOperand &MO, unsigned Reg, const TargetRegisterInfo &TRI) { - if (unsigned SubIdx = MO.getSubReg()) { - // Insert the physical subreg and reset the subreg field. - MO.setReg(TRI.getSubReg(Reg, SubIdx)); - MO.setSubReg(0); - - // Any def, dead, and kill flags apply to the full virtual register, so they - // also apply to the full physical register. Add imp-def/dead and imp-kill - // as needed. + if (MO.getSubReg()) { + MO.substPhysReg(Reg, TRI); + + // Any kill flags apply to the full virtual register, so they also apply to + // the full physical register. + // We assume that partial defs have already been decorated with a super-reg + // operand by LiveIntervals. MachineInstr &MI = *MO.getParent(); - if (MO.isDef()) - if (MO.isDead()) - MI.addRegisterDead(Reg, &TRI, /*AddIfNotFound=*/ true); - else - MI.addRegisterDefined(Reg, &TRI); - else if (!MO.isUndef() && - (MO.isKill() || - MI.isRegTiedToDefOperand(&MO-&MI.getOperand(0)))) + if (MO.isUse() && !MO.isUndef() && + (MO.isKill() || MI.isRegTiedToDefOperand(&MO-&MI.getOperand(0)))) MI.addRegisterKilled(Reg, &TRI, /*AddIfNotFound=*/ true); } else { MO.setReg(Reg);