+ const Function* F = MF.getFunction();
+ const TargetMachine& TM = MF.getTarget();
+
+ // Calculate this function's optimization goal.
+ unsigned OptimizationGoal;
+ if (F->hasFnAttribute(Attribute::OptimizeNone))
+ // For best debugging illusion, speed and small size sacrificed
+ OptimizationGoal = 6;
+ else if (F->optForMinSize())
+ // Aggressively for small size, speed and debug illusion sacrificed
+ OptimizationGoal = 4;
+ else if (F->optForSize())
+ // For small size, but speed and debugging illusion preserved
+ OptimizationGoal = 3;
+ else if (TM.getOptLevel() == CodeGenOpt::Aggressive)
+ // Aggressively for speed, small size and debug illusion sacrificed
+ OptimizationGoal = 2;
+ else if (TM.getOptLevel() > CodeGenOpt::None)
+ // For speed, but small size and good debug illusion preserved
+ OptimizationGoal = 1;
+ else // TM.getOptLevel() == CodeGenOpt::None
+ // For good debugging, but speed and small size preserved
+ OptimizationGoal = 5;
+
+ // Combine a new optimization goal with existing ones.
+ if (OptimizationGoals == -1) // uninitialized goals
+ OptimizationGoals = OptimizationGoal;
+ else if (OptimizationGoals != OptimizationGoal) // conflicting goals
+ OptimizationGoals = 0;