diff options
| -rw-r--r-- | lib/CodeGen/CriticalAntiDepBreaker.cpp | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/lib/CodeGen/CriticalAntiDepBreaker.cpp b/lib/CodeGen/CriticalAntiDepBreaker.cpp index 44ff9b3cad..4a62cb7d11 100644 --- a/lib/CodeGen/CriticalAntiDepBreaker.cpp +++ b/lib/CodeGen/CriticalAntiDepBreaker.cpp @@ -130,21 +130,25 @@ void CriticalAntiDepBreaker::Observe(MachineInstr *MI, unsigned Count, return; assert(Count < InsertPosIndex && "Instruction index out of expected range!"); - // Any register which was defined within the previous scheduling region - // may have been rescheduled and its lifetime may overlap with registers - // in ways not reflected in our current liveness state. For each such - // register, adjust the liveness state to be conservatively correct. - for (unsigned Reg = 0; Reg != TRI->getNumRegs(); ++Reg) - if (DefIndices[Reg] < InsertPosIndex && DefIndices[Reg] >= Count) { - assert(KillIndices[Reg] == ~0u && "Clobbered register is live!"); - - // Mark this register to be non-renamable. + for (unsigned Reg = 0; Reg != TRI->getNumRegs(); ++Reg) { + if (KillIndices[Reg] != ~0u) { + // If Reg is currently live, then mark that it can't be renamed as + // we don't know the extent of its live-range anymore (now that it + // has been scheduled). + Classes[Reg] = reinterpret_cast<TargetRegisterClass *>(-1); + KillIndices[Reg] = Count; + } else if (DefIndices[Reg] < InsertPosIndex && DefIndices[Reg] >= Count) { + // Any register which was defined within the previous scheduling region + // may have been rescheduled and its lifetime may overlap with registers + // in ways not reflected in our current liveness state. For each such + // register, adjust the liveness state to be conservatively correct. Classes[Reg] = reinterpret_cast<TargetRegisterClass *>(-1); // Move the def index to the end of the previous region, to reflect // that the def could theoretically have been scheduled at the end. DefIndices[Reg] = InsertPosIndex; } + } PrescanInstruction(MI); ScanInstruction(MI, Count); @@ -580,7 +584,7 @@ BreakAntiDependencies(const std::vector<SUnit>& SUnits, } // We just went back in time and modified history; the - // liveness information for the anti-depenence reg is now + // liveness information for the anti-dependence reg is now // inconsistent. Set the state as if it were dead. Classes[NewReg] = Classes[AntiDepReg]; DefIndices[NewReg] = DefIndices[AntiDepReg]; |