mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-19 19:29:31 +00:00
info (since multiple reg types may share the same reg class). (2) Remove machine-specific regalloc. methods that are no longer needed. In particular, arguments and return value from a call do not need machine-specific code for allocation. (3) Rename TargetRegInfo::getRegType variants to avoid unintentional overloading when an include file is omitted. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7329 91177308-0d34-0410-b5e6-96231b3b80d8
268 lines
8.3 KiB
C++
268 lines
8.3 KiB
C++
//===-- RegClass.cpp -----------------------------------------------------===//
|
|
//
|
|
// class RegClass for coloring-based register allocation for LLVM.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "RegClass.h"
|
|
#include "RegAllocCommon.h"
|
|
#include "llvm/CodeGen/IGNode.h"
|
|
#include "llvm/Target/TargetRegInfo.h"
|
|
using std::cerr;
|
|
|
|
//----------------------------------------------------------------------------
|
|
// This constructor inits IG. The actual matrix is created by a call to
|
|
// createInterferenceGraph() above.
|
|
//----------------------------------------------------------------------------
|
|
RegClass::RegClass(const Function *M,
|
|
const TargetRegInfo *_MRI_,
|
|
const TargetRegClassInfo *_MRC_)
|
|
: Meth(M), MRI(_MRI_), MRC(_MRC_),
|
|
RegClassID( _MRC_->getRegClassID() ),
|
|
IG(this), IGNodeStack() {
|
|
if( DEBUG_RA >= RA_DEBUG_Interference)
|
|
cerr << "Created Reg Class: " << RegClassID << "\n";
|
|
|
|
IsColorUsedArr.resize(MRC->getNumOfAllRegs());
|
|
}
|
|
|
|
|
|
|
|
//----------------------------------------------------------------------------
|
|
// Main entry point for coloring a register class.
|
|
//----------------------------------------------------------------------------
|
|
void RegClass::colorAllRegs()
|
|
{
|
|
if(DEBUG_RA >= RA_DEBUG_Coloring)
|
|
cerr << "Coloring IG of reg class " << RegClassID << " ...\n";
|
|
|
|
// pre-color IGNodes
|
|
pushAllIGNodes(); // push all IG Nodes
|
|
|
|
unsigned int StackSize = IGNodeStack.size();
|
|
IGNode *CurIGNode;
|
|
|
|
// for all LRs on stack
|
|
for( unsigned int IGN=0; IGN < StackSize; IGN++) {
|
|
|
|
CurIGNode = IGNodeStack.top(); // pop the IGNode on top of stack
|
|
IGNodeStack.pop();
|
|
colorIGNode (CurIGNode); // color it
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
//----------------------------------------------------------------------------
|
|
// The method for pushing all IGNodes on to the stack.
|
|
//----------------------------------------------------------------------------
|
|
void RegClass::pushAllIGNodes()
|
|
{
|
|
bool NeedMoreSpills;
|
|
|
|
|
|
IG.setCurDegreeOfIGNodes(); // calculate degree of IGNodes
|
|
|
|
// push non-constrained IGNodes
|
|
bool PushedAll = pushUnconstrainedIGNodes();
|
|
|
|
if( DEBUG_RA >= RA_DEBUG_Coloring) {
|
|
cerr << " Puhsed all-unconstrained IGNodes. ";
|
|
if( PushedAll ) cerr << " No constrained nodes left.";
|
|
cerr << "\n";
|
|
}
|
|
|
|
if( PushedAll ) // if NO constrained nodes left
|
|
return;
|
|
|
|
|
|
// now, we have constrained nodes. So, push one of them (the one with min
|
|
// spill cost) and try to push the others as unConstrained nodes.
|
|
// Repeat this.
|
|
|
|
do {
|
|
//get node with min spill cost
|
|
//
|
|
IGNode *IGNodeSpill = getIGNodeWithMinSpillCost();
|
|
|
|
// push that node on to stack
|
|
//
|
|
IGNodeStack.push(IGNodeSpill);
|
|
|
|
// set its OnStack flag and decrement degree of neighs
|
|
//
|
|
IGNodeSpill->pushOnStack();
|
|
|
|
// now push NON-constrined ones, if any
|
|
//
|
|
NeedMoreSpills = !pushUnconstrainedIGNodes();
|
|
|
|
if (DEBUG_RA >= RA_DEBUG_Coloring)
|
|
cerr << "\nConstrained IG Node found !@!" << IGNodeSpill->getIndex();
|
|
|
|
} while(NeedMoreSpills); // repeat until we have pushed all
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
//--------------------------------------------------------------------------
|
|
// This method goes thru all IG nodes in the IGNodeList of an IG of a
|
|
// register class and push any unconstrained IG node left (that is not
|
|
// already pushed)
|
|
//--------------------------------------------------------------------------
|
|
|
|
bool RegClass::pushUnconstrainedIGNodes()
|
|
{
|
|
// # of LRs for this reg class
|
|
unsigned int IGNodeListSize = IG.getIGNodeList().size();
|
|
bool pushedall = true;
|
|
|
|
// a pass over IGNodeList
|
|
for( unsigned i =0; i < IGNodeListSize; i++) {
|
|
|
|
// get IGNode i from IGNodeList
|
|
IGNode *IGNode = IG.getIGNodeList()[i];
|
|
|
|
if( !IGNode ) // can be null due to merging
|
|
continue;
|
|
|
|
// if already pushed on stack, continue. This can happen since this
|
|
// method can be called repeatedly until all constrained nodes are
|
|
// pushed
|
|
if( IGNode->isOnStack() )
|
|
continue;
|
|
// if the degree of IGNode is lower
|
|
if( (unsigned) IGNode->getCurDegree() < MRC->getNumOfAvailRegs()) {
|
|
IGNodeStack.push( IGNode ); // push IGNode on to the stack
|
|
IGNode->pushOnStack(); // set OnStack and dec deg of neighs
|
|
|
|
if (DEBUG_RA >= RA_DEBUG_Coloring) {
|
|
cerr << " pushed un-constrained IGNode " << IGNode->getIndex() ;
|
|
cerr << " on to stack\n";
|
|
}
|
|
}
|
|
else pushedall = false; // we didn't push all live ranges
|
|
|
|
} // for
|
|
|
|
// returns true if we pushed all live ranges - else false
|
|
return pushedall;
|
|
}
|
|
|
|
|
|
|
|
//----------------------------------------------------------------------------
|
|
// Get the IGNode withe the minimum spill cost
|
|
//----------------------------------------------------------------------------
|
|
IGNode * RegClass::getIGNodeWithMinSpillCost()
|
|
{
|
|
|
|
unsigned int IGNodeListSize = IG.getIGNodeList().size();
|
|
double MinSpillCost = 0;
|
|
IGNode *MinCostIGNode = NULL;
|
|
bool isFirstNode = true;
|
|
|
|
// pass over IGNodeList to find the IGNode with minimum spill cost
|
|
// among all IGNodes that are not yet pushed on to the stack
|
|
//
|
|
for( unsigned int i =0; i < IGNodeListSize; i++) {
|
|
IGNode *IGNode = IG.getIGNodeList()[i];
|
|
|
|
if( ! IGNode ) // can be null due to merging
|
|
continue;
|
|
|
|
if( ! IGNode->isOnStack() ) {
|
|
|
|
double SpillCost = (double) IGNode->getParentLR()->getSpillCost() /
|
|
(double) (IGNode->getCurDegree() + 1);
|
|
|
|
if( isFirstNode ) { // for the first IG node
|
|
MinSpillCost = SpillCost;
|
|
MinCostIGNode = IGNode;
|
|
isFirstNode = false;
|
|
}
|
|
|
|
else if( MinSpillCost > SpillCost) {
|
|
MinSpillCost = SpillCost;
|
|
MinCostIGNode = IGNode;
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
assert( MinCostIGNode && "No IGNode to spill");
|
|
return MinCostIGNode;
|
|
}
|
|
|
|
|
|
|
|
//----------------------------------------------------------------------------
|
|
// Color the IGNode using the machine specific code.
|
|
//----------------------------------------------------------------------------
|
|
void RegClass::colorIGNode(IGNode *const Node)
|
|
{
|
|
|
|
if( ! Node->hasColor() ) { // not colored as an arg etc.
|
|
|
|
// init all elements of to IsColorUsedAr false;
|
|
clearColorsUsed();
|
|
|
|
// initialize all colors used by neighbors of this node to true
|
|
LiveRange *LR = Node->getParentLR();
|
|
unsigned NumNeighbors = Node->getNumOfNeighbors();
|
|
for (unsigned n=0; n < NumNeighbors; n++) {
|
|
IGNode *NeighIGNode = Node->getAdjIGNode(n);
|
|
LiveRange *NeighLR = NeighIGNode->getParentLR();
|
|
|
|
// Don't use a color if it is in use by the neighbour,
|
|
// or is suggested for use by the neighbour,
|
|
// markColorsUsed() should be given the color and the reg type for
|
|
// LR, not for NeighLR, because it should mark registers used based on
|
|
// the type we are looking for, not on the regType for the neighbour.
|
|
if (NeighLR->hasColor())
|
|
this->markColorsUsed(NeighLR->getColor(),
|
|
MRI->getRegTypeForLR(NeighLR),
|
|
MRI->getRegTypeForLR(LR)); // use LR, not NeighLR
|
|
else if (NeighLR->hasSuggestedColor() &&
|
|
NeighLR->isSuggestedColorUsable())
|
|
this->markColorsUsed(NeighLR->getSuggestedColor(),
|
|
MRI->getRegTypeForLR(NeighLR),
|
|
MRI->getRegTypeForLR(LR)); // use LR, not NeighLR
|
|
}
|
|
|
|
// call the target specific code for coloring
|
|
//
|
|
MRC->colorIGNode(Node, IsColorUsedArr);
|
|
}
|
|
else {
|
|
if( DEBUG_RA >= RA_DEBUG_Coloring) {
|
|
cerr << " Node " << Node->getIndex();
|
|
cerr << " already colored with color " << Node->getColor() << "\n";
|
|
}
|
|
}
|
|
|
|
|
|
if( !Node->hasColor() ) {
|
|
if( DEBUG_RA >= RA_DEBUG_Coloring) {
|
|
cerr << " Node " << Node->getIndex();
|
|
cerr << " - could not find a color (needs spilling)\n";
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
void RegClass::printIGNodeList() const {
|
|
std::cerr << "IG Nodes for Register Class " << RegClassID << ":" << "\n";
|
|
IG.printIGNodeList();
|
|
}
|
|
|
|
void RegClass::printIG() {
|
|
std::cerr << "IG for Register Class " << RegClassID << ":" << "\n";
|
|
IG.printIG();
|
|
}
|
|
|
|
|