Great renaming: Sparc --> SparcV9

llvm-svn: 11826
diff --git a/llvm/lib/Target/SparcV9/SparcV9RegClassInfo.cpp b/llvm/lib/Target/SparcV9/SparcV9RegClassInfo.cpp
new file mode 100644
index 0000000..d0fe117
--- /dev/null
+++ b/llvm/lib/Target/SparcV9/SparcV9RegClassInfo.cpp
@@ -0,0 +1,397 @@
+//===-- SparcV9RegClassInfo.cpp - Register class def'ns for SparcV9 -----------===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the register classes used by the SparcV9 target description.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Type.h"
+#include "SparcV9RegClassInfo.h"
+#include "SparcV9Internals.h"
+#include "SparcV9RegInfo.h"
+#include "RegAlloc/RegAllocCommon.h"
+#include "RegAlloc/IGNode.h"
+
+namespace llvm {
+
+//-----------------------------------------------------------------------------
+// Int Register Class - method for coloring a node in the interference graph.
+//
+// Algorithm:
+//     Record the colors/suggested colors of all neighbors.
+//
+//     If there is a suggested color, try to allocate it
+//     If there is no call interf, try to allocate volatile, then non volatile
+//     If there is call interf, try to allocate non-volatile. If that fails
+//     try to allocate a volatile and insert save across calls
+//     If both above fail, spill.
+//  
+//-----------------------------------------------------------------------------
+void SparcV9IntRegClass::colorIGNode(IGNode * Node,
+                               const std::vector<bool> &IsColorUsedArr) const
+{
+  LiveRange *LR = Node->getParentLR();
+
+  if (DEBUG_RA) {
+    std::cerr << "\nColoring LR [CallInt=" << LR->isCallInterference() <<"]:"; 
+    printSet(*LR);
+  }
+
+  if (LR->hasSuggestedColor()) {
+    unsigned SugCol = LR->getSuggestedColor();
+    if (!IsColorUsedArr[SugCol]) {
+      if (LR->isSuggestedColorUsable()) {
+	// if the suggested color is volatile, we should use it only if
+	// there are no call interferences. Otherwise, it will get spilled.
+	if (DEBUG_RA)
+	  std::cerr << "\n  -Coloring with sug color: " << SugCol;
+
+	LR->setColor(LR->getSuggestedColor());
+	return;
+      } else if(DEBUG_RA) {
+        std::cerr << "\n Couldn't alloc Sug col - LR volatile & calls interf";
+      }
+    } else if (DEBUG_RA) {                // can't allocate the suggested col
+      std::cerr << "\n  Could NOT allocate the suggested color (already used) ";
+      printSet(*LR); std::cerr << "\n";
+    }
+  }
+
+  unsigned SearchStart;                 // start pos of color in pref-order
+  bool ColorFound= false;               // have we found a color yet?
+
+  //if this Node is between calls
+  if (! LR->isCallInterference()) { 
+    // start with volatiles (we can  allocate volatiles safely)
+    SearchStart = SparcV9IntRegClass::StartOfAllRegs;  
+  } else {           
+    // start with non volatiles (no non-volatiles)
+    SearchStart =  SparcV9IntRegClass::StartOfNonVolatileRegs;  
+  }
+
+  unsigned c=0;                         // color
+ 
+  // find first unused color
+  for (c=SearchStart; c < SparcV9IntRegClass::NumOfAvailRegs; c++) { 
+    if (!IsColorUsedArr[c]) {
+      ColorFound = true;
+      break;
+    }
+  }
+
+  if (ColorFound) {
+    LR->setColor(c);                  // first color found in preferred order
+    if (DEBUG_RA) std::cerr << "\n  Colored after first search with col " << c;
+  }
+
+  // if color is not found because of call interference
+  // try even finding a volatile color and insert save across calls
+  //
+  else if (LR->isCallInterference()) {
+    // start from 0 - try to find even a volatile this time
+    SearchStart = SparcV9IntRegClass::StartOfAllRegs;  
+
+    // find first unused volatile color
+    for(c=SearchStart; c < SparcV9IntRegClass::StartOfNonVolatileRegs; c++) { 
+      if (! IsColorUsedArr[c]) {
+        ColorFound = true;
+        break;
+      }
+    }
+
+    if (ColorFound) { 
+      LR->setColor(c);  
+      //  get the live range corresponding to live var
+      // since LR span across calls, must save across calls 
+      //
+      LR->markForSaveAcrossCalls();       
+      if (DEBUG_RA)
+        std::cerr << "\n  Colored after SECOND search with col " << c;
+    }
+  }
+
+
+  // If we couldn't find a color regardless of call interference - i.e., we
+  // don't have either a volatile or non-volatile color left
+  //
+  if (!ColorFound)  
+    LR->markForSpill();               // no color found - must spill
+}
+
+//-----------------------------------------------------------------------------
+// Int CC Register Class - method for coloring a node in the interference graph.
+//
+// Algorithm:
+//
+//     If (node has any interferences)
+//         /* all interference operations can use only one register! */
+//         mark the LR for spilling
+//     else {
+//         if (the LR is a 64-bit comparison) use %xcc
+//         else /*32-bit or smaller*/ use %icc
+//     }
+// 
+// Note: The third name (%ccr) is essentially an assembly mnemonic and
+// depends solely on the opcode, so the name can be chosen in EmitAssembly.
+//-----------------------------------------------------------------------------
+void SparcV9IntCCRegClass::colorIGNode(IGNode *Node,
+                                 const std::vector<bool> &IsColorUsedArr) const
+{
+  if (Node->getNumOfNeighbors() > 0)
+    Node->getParentLR()->markForSpill();
+
+  // Mark the appropriate register in any case (even if it needs to be spilled)
+  // because there is only one possible register, but more importantly, the
+  // spill algorithm cannot find it.  In particular, we have to choose
+  // whether to use %xcc or %icc based on type of value compared
+  // 
+  const LiveRange* ccLR = Node->getParentLR();
+  const Type* setCCType = (* ccLR->begin())->getType(); // any Value in LR
+  assert(setCCType->isIntegral() || isa<PointerType>(setCCType));
+  int ccReg = ((isa<PointerType>(setCCType) || setCCType == Type::LongTy)
+               ? xcc : icc);
+
+#ifndef NDEBUG
+  // Let's just make sure values of two different types have not been
+  // coalesced into this LR.
+  for (ValueSet::const_iterator I=ccLR->begin(), E=ccLR->end(); I!=E; ++I) {
+    const Type* ccType = (*I)->getType();
+    assert((ccReg == xcc && (isa<PointerType>(ccType)
+                             || ccType == Type::LongTy)) ||
+           (ccReg == icc && ccType->isIntegral() && ccType != Type::LongTy)
+           && "Comparisons needing different intCC regs coalesced in LR!");
+  }
+#endif
+
+  Node->setColor(ccReg);                // only one int cc reg is available
+}
+
+
+void SparcV9FloatCCRegClass::colorIGNode(IGNode *Node,
+                                const std::vector<bool> &IsColorUsedArr) const {
+  for(unsigned c = 0; c != 4; ++c)
+    if (!IsColorUsedArr[c]) { // find unused color
+      Node->setColor(c);   
+      return;
+    }
+  
+  Node->getParentLR()->markForSpill();
+}
+
+
+
+//-----------------------------------------------------------------------------
+// Float Register Class - method for coloring a node in the interference graph.
+//
+// Algorithm:
+//
+//     If the LR is a double try to allocate f32 - f63
+//     If the above fails or LR is single precision
+//        If the LR does not interfere with a call
+//	   start allocating from f0
+//	Else start allocating from f6
+//     If a color is still not found because LR interferes with a call
+//        Search in f0 - f6. If found mark for spill across calls.
+//     If a color is still not fond, mark for spilling
+//
+//----------------------------------------------------------------------------
+void SparcV9FloatRegClass::colorIGNode(IGNode * Node,
+                                 const std::vector<bool> &IsColorUsedArr) const
+{
+  LiveRange *LR = Node->getParentLR();
+
+#ifndef NDEBUG
+  // Check that the correct colors have been are marked for fp-doubles.
+  // 
+  // FIXME: This is old code that is no longer needed.  Temporarily converting
+  // it into a big assertion just to check that the replacement logic
+  // (invoking SparcV9FloatRegClass::markColorsUsed() directly from
+  // RegClass::colorIGNode) works correctly.
+  // 
+  // In fact, this entire function should be identical to
+  // SparcV9IntRegClass::colorIGNode(), and perhaps can be
+  // made into a general case in CodeGen/RegAlloc/RegClass.cpp.  
+  // 
+  unsigned NumNeighbors =  Node->getNumOfNeighbors();   // total # of neighbors
+  for(unsigned n=0; n < NumNeighbors; n++) {            // for each neigh 
+    IGNode *NeighIGNode = Node->getAdjIGNode(n);
+    LiveRange *NeighLR = NeighIGNode->getParentLR();
+    
+    if (NeighLR->hasColor()) {
+      assert(IsColorUsedArr[ NeighLR->getColor() ]);
+      if (NeighLR->getType() == Type::DoubleTy)
+        assert(IsColorUsedArr[ NeighLR->getColor()+1 ]);
+      
+    } else if (NeighLR->hasSuggestedColor() &&
+               NeighLR-> isSuggestedColorUsable() ) {
+
+      // if the neighbour can use the suggested color 
+      assert(IsColorUsedArr[ NeighLR->getSuggestedColor() ]);
+      if (NeighLR->getType() == Type::DoubleTy)
+        assert(IsColorUsedArr[ NeighLR->getSuggestedColor()+1 ]);
+    }
+  }
+#endif
+
+  // **NOTE: We don't check for call interferences in allocating suggested
+  // color in this class since ALL registers are volatile. If this fact
+  // changes, we should change the following part 
+  //- see SparcV9IntRegClass::colorIGNode()
+  // 
+  if( LR->hasSuggestedColor() ) {
+    if( ! IsColorUsedArr[ LR->getSuggestedColor() ] ) {
+      LR->setColor(  LR->getSuggestedColor() );
+      return;
+    } else if (DEBUG_RA)  {                 // can't allocate the suggested col
+      std::cerr << " Could NOT allocate the suggested color for LR ";
+      printSet(*LR); std::cerr << "\n";
+    }
+  }
+
+
+  int ColorFound = -1;               // have we found a color yet?
+  bool isCallInterf = LR->isCallInterference();
+
+  // if value is a double - search the double only region (f32 - f63)
+  // i.e. we try to allocate f32 - f63 first for doubles since singles
+  // cannot go there. By doing that, we provide more space for singles
+  // in f0 - f31
+  //
+  if (LR->getType() == Type::DoubleTy)       
+    ColorFound = findFloatColor( LR, 32, 64, IsColorUsedArr );
+
+  if (ColorFound >= 0) {               // if we could find a color
+    LR->setColor(ColorFound);                
+    return;
+  } else { 
+
+    // if we didn't find a color because the LR was single precision or
+    // all f32-f63 range is filled, we try to allocate a register from
+    // the f0 - f31 region 
+
+    unsigned SearchStart;                 // start pos of color in pref-order
+
+    //if this Node is between calls (i.e., no call interferences )
+    if (! isCallInterf) {
+      // start with volatiles (we can  allocate volatiles safely)
+      SearchStart = SparcV9FloatRegClass::StartOfAllRegs;  
+    } else {
+      // start with non volatiles (no non-volatiles)
+      SearchStart =  SparcV9FloatRegClass::StartOfNonVolatileRegs;  
+    }
+    
+    ColorFound = findFloatColor(LR, SearchStart, 32, IsColorUsedArr);
+  }
+
+  if (ColorFound >= 0) {               // if we could find a color
+    LR->setColor(ColorFound);                  
+    return;
+  } else if (isCallInterf) { 
+    // We are here because there is a call interference and no non-volatile
+    // color could be found.
+    // Now try to allocate even a volatile color
+    ColorFound = findFloatColor(LR, SparcV9FloatRegClass::StartOfAllRegs, 
+				SparcV9FloatRegClass::StartOfNonVolatileRegs,
+				IsColorUsedArr);
+  }
+
+  if (ColorFound >= 0) {
+    LR->setColor(ColorFound);         // first color found in preferred order
+    LR->markForSaveAcrossCalls();  
+  } else {
+    // we are here because no color could be found
+    LR->markForSpill();               // no color found - must spill
+  }
+}
+
+//-----------------------------------------------------------------------------
+// This method marks the registers used for a given register number.
+// This marks a single register for Float regs, but the R,R+1 pair
+// for double-precision registers.
+//-----------------------------------------------------------------------------
+
+void SparcV9FloatRegClass::markColorsUsed(unsigned RegInClass,
+                                        int UserRegType,
+                                        int RegTypeWanted,
+                                    std::vector<bool> &IsColorUsedArr) const
+{
+  if (UserRegType == SparcV9RegInfo::FPDoubleRegType ||
+      RegTypeWanted == SparcV9RegInfo::FPDoubleRegType) {
+    // This register is used as or is needed as a double-precision reg.
+    // We need to mark the [even,odd] pair corresponding to this reg.
+    // Get the even numbered register corresponding to this reg.
+    unsigned EvenRegInClass = RegInClass & ~1u;
+    assert(EvenRegInClass+1 < NumOfAllRegs &&
+           EvenRegInClass+1 < IsColorUsedArr.size());
+    IsColorUsedArr[EvenRegInClass]   = true;
+    IsColorUsedArr[EvenRegInClass+1] = true;
+  }
+  else {
+    assert(RegInClass < NumOfAllRegs && RegInClass < IsColorUsedArr.size());
+    assert(UserRegType == RegTypeWanted
+           && "Something other than FP single/double types share a reg class?");
+    IsColorUsedArr[RegInClass] = true;
+  }
+}
+
+// This method finds unused registers of the specified register type,
+// using the given "used" flag array IsColorUsedArr.  It checks a single
+// entry in the array directly for float regs, and checks the pair [R,R+1]
+// for double-precision registers
+// It returns -1 if no unused color is found.
+// 
+int SparcV9FloatRegClass::findUnusedColor(int RegTypeWanted,
+                                const std::vector<bool> &IsColorUsedArr) const
+{
+  if (RegTypeWanted == SparcV9RegInfo::FPDoubleRegType) {
+    unsigned NC = 2 * this->getNumOfAvailRegs();
+    assert(IsColorUsedArr.size() == NC && "Invalid colors-used array");
+    for (unsigned c = 0; c < NC; c+=2)
+      if (!IsColorUsedArr[c]) {
+        assert(!IsColorUsedArr[c+1] && "Incorrect used regs for FP double!");
+	return c;
+      }
+    return -1;
+  }
+  else
+    return TargetRegClassInfo::findUnusedColor(RegTypeWanted, IsColorUsedArr);
+}
+
+//-----------------------------------------------------------------------------
+// Helper method for coloring a node of Float Reg class.
+// Finds the first available color in the range [Start,End] depending on the
+// type of the Node (i.e., float/double)
+//-----------------------------------------------------------------------------
+
+int SparcV9FloatRegClass::findFloatColor(const LiveRange *LR, 
+                                       unsigned Start,
+                                       unsigned End, 
+                               const std::vector<bool> &IsColorUsedArr) const
+{
+  if (LR->getType() == Type::DoubleTy) { 
+    // find first unused color for a double 
+    assert(Start % 2 == 0 && "Odd register number could be used for double!");
+    for (unsigned c=Start; c < End ; c+= 2)
+      if (!IsColorUsedArr[c]) {
+        assert(!IsColorUsedArr[c+1] &&
+               "Incorrect marking of used regs for SparcV9 FP double!");
+	return c;
+      }
+  } else {
+    // find first unused color for a single
+    for (unsigned c = Start; c < End; c++)
+      if (!IsColorUsedArr[c])
+        return c;
+  }
+
+  return -1;
+
+}
+
+} // End llvm namespace