diff options
Diffstat (limited to 'lib/CodeGen/RegAllocGreedy.cpp')
-rw-r--r-- | lib/CodeGen/RegAllocGreedy.cpp | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/lib/CodeGen/RegAllocGreedy.cpp b/lib/CodeGen/RegAllocGreedy.cpp index aa7c178..901b993 100644 --- a/lib/CodeGen/RegAllocGreedy.cpp +++ b/lib/CodeGen/RegAllocGreedy.cpp @@ -44,6 +44,7 @@ #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/Timer.h" #include "llvm/Support/raw_ostream.h" +#include "llvm/Target/TargetSubtargetInfo.h" #include <queue> using namespace llvm; @@ -79,6 +80,12 @@ ExhaustiveSearch("exhaustive-register-search", cl::NotHidden, cl::desc("Exhaustive Search for registers bypassing the depth " "and interference cutoffs of last chance recoloring")); +static cl::opt<bool> EnableLocalReassignment( + "enable-local-reassign", cl::Hidden, + cl::desc("Local reassignment can yield better allocation decisions, but " + "may be compile time intensive"), + cl::init(false)); + // FIXME: Find a good default for this flag and remove the flag. static cl::opt<unsigned> CSRFirstTimeCost("regalloc-csr-first-time-cost", @@ -285,6 +292,10 @@ class RAGreedy : public MachineFunctionPass, /// Callee-save register cost, calculated once per machine function. BlockFrequency CSRCost; + /// Run or not the local reassignment heuristic. This information is + /// obtained from the TargetSubtargetInfo. + bool EnableLocalReassign; + public: RAGreedy(); @@ -731,7 +742,7 @@ bool RAGreedy::canEvictInterference(LiveInterval &VirtReg, unsigned PhysReg, // Evicting another local live range in this case could lead to suboptimal // coloring. if (!MaxCost.isMax() && IsLocal && LIS->intervalIsInOneMBB(*Intf) && - !canReassign(*Intf, PhysReg)) { + (!EnableLocalReassign || !canReassign(*Intf, PhysReg))) { return false; } } @@ -2308,9 +2319,14 @@ bool RAGreedy::runOnMachineFunction(MachineFunction &mf) { << "********** Function: " << mf.getName() << '\n'); MF = &mf; - TRI = MF->getTarget().getRegisterInfo(); - TII = MF->getTarget().getInstrInfo(); + const TargetMachine &TM = MF->getTarget(); + TRI = TM.getRegisterInfo(); + TII = TM.getInstrInfo(); RCI.runOnMachineFunction(mf); + + EnableLocalReassign = EnableLocalReassignment || + TM.getSubtargetImpl()->enableRALocalReassignment(TM.getOptLevel()); + if (VerifyEnabled) MF->verify(this, "Before greedy register allocator"); |