Revert "Convert liveness tracking to work on a sub-register level instead of just...

[oota-llvm.git] / lib / CodeGen / TargetRegisterInfo.cpp

diff --git a/lib/CodeGen/TargetRegisterInfo.cpp b/lib/CodeGen/TargetRegisterInfo.cpp
index 49dc3f9f17af79ae857f2b8ac048e804ea204fb1..5a1524364b6b5249bfa1f37f0db2a54334f8b53a 100644 (file)
--- a/lib/CodeGen/TargetRegisterInfo.cpp
+++ b/lib/CodeGen/TargetRegisterInfo.cpp
@@ -13,18 +13,22 @@
 
 #include "llvm/Target/TargetRegisterInfo.h"
 #include "llvm/ADT/BitVector.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/VirtRegMap.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Target/TargetMachine.h"
 
 using namespace llvm;
 
 TargetRegisterInfo::TargetRegisterInfo(const TargetRegisterInfoDesc *ID,
                              regclass_iterator RCB, regclass_iterator RCE,
                              const char *const *SRINames,
-                             const unsigned *SRILaneMasks)
+                             const unsigned *SRILaneMasks,
+                             unsigned SRICoveringLanes)
   : InfoDesc(ID), SubRegIndexNames(SRINames),
     SubRegIndexLaneMasks(SRILaneMasks),
-    RegClassBegin(RCB), RegClassEnd(RCE) {
+    RegClassBegin(RCB), RegClassEnd(RCE),
+    CoveringLanes(SRICoveringLanes) {
 }
 
 TargetRegisterInfo::~TargetRegisterInfo() {}
@@ -69,6 +73,14 @@ void PrintRegUnit::print(raw_ostream &OS) const {
     OS << '~' << TRI->getName(*Roots);
 }
 
+void PrintVRegOrUnit::print(raw_ostream &OS) const {
+  if (TRI && TRI->isVirtualRegister(Unit)) {
+    OS << "%vreg" << TargetRegisterInfo::virtReg2Index(Unit);
+    return;
+  }
+  PrintRegUnit::print(OS);
+}
+
 /// getAllocatableClass - Return the maximal subclass of the given register
 /// class that is alloctable, or NULL.
 const TargetRegisterClass *
@@ -81,7 +93,7 @@ TargetRegisterInfo::getAllocatableClass(const TargetRegisterClass *RC) const {
        Base < BaseE; Base += 32) {
     unsigned Idx = Base;
     for (unsigned Mask = *SubClass++; Mask; Mask >>= 1) {
-      unsigned Offset = CountTrailingZeros_32(Mask);
+      unsigned Offset = countTrailingZeros(Mask);
       const TargetRegisterClass *SubRC = getRegClass(Idx + Offset);
       if (SubRC->isAllocatable())
         return SubRC;
@@ -151,7 +163,7 @@ const TargetRegisterClass *firstCommonClass(const uint32_t *A,
                                             const TargetRegisterInfo *TRI) {
   for (unsigned I = 0, E = TRI->getNumRegClasses(); I < E; I += 32)
     if (unsigned Common = *A++ & *B++)
-      return TRI->getRegClass(I + CountTrailingZeros_32(Common));
+      return TRI->getRegClass(I + countTrailingZeros(Common));
   return 0;
 }
 
@@ -246,3 +258,38 @@ getCommonSuperRegClass(const TargetRegisterClass *RCA, unsigned SubA,
   }
   return BestRC;
 }
+
+// Compute target-independent register allocator hints to help eliminate copies.
+void
+TargetRegisterInfo::getRegAllocationHints(unsigned VirtReg,
+                                          ArrayRef<MCPhysReg> Order,
+                                          SmallVectorImpl<MCPhysReg> &Hints,
+                                          const MachineFunction &MF,
+                                          const VirtRegMap *VRM) const {
+  const MachineRegisterInfo &MRI = MF.getRegInfo();
+  std::pair<unsigned, unsigned> Hint = MRI.getRegAllocationHint(VirtReg);
+
+  // Hints with HintType != 0 were set by target-dependent code.
+  // Such targets must provide their own implementation of
+  // TRI::getRegAllocationHints to interpret those hint types.
+  assert(Hint.first == 0 && "Target must implement TRI::getRegAllocationHints");
+
+  // Target-independent hints are either a physical or a virtual register.
+  unsigned Phys = Hint.second;
+  if (VRM && isVirtualRegister(Phys))
+    Phys = VRM->getPhys(Phys);
+
+  // Check that Phys is a valid hint in VirtReg's register class.
+  if (!isPhysicalRegister(Phys))
+    return;
+  if (MRI.isReserved(Phys))
+    return;
+  // Check that Phys is in the allocation order. We shouldn't heed hints
+  // from VirtReg's register class if they aren't in the allocation order. The
+  // target probably has a reason for removing the register.
+  if (std::find(Order.begin(), Order.end(), Phys) == Order.end())
+    return;
+
+  // All clear, tell the register allocator to prefer this register.
+  Hints.push_back(Phys);
+}