1 //===-- SparcV9RegClassInfo.cpp - Register class def'ns for SparcV9 -----------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the register classes used by the SparcV9 target description.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Type.h"
15 #include "SparcV9RegClassInfo.h"
16 #include "SparcV9Internals.h"
17 #include "SparcV9RegInfo.h"
18 #include "RegAlloc/RegAllocCommon.h"
19 #include "RegAlloc/IGNode.h"
23 //-----------------------------------------------------------------------------
24 // Int Register Class - method for coloring a node in the interference graph.
27 // Record the colors/suggested colors of all neighbors.
29 // If there is a suggested color, try to allocate it
30 // If there is no call interf, try to allocate volatile, then non volatile
31 // If there is call interf, try to allocate non-volatile. If that fails
32 // try to allocate a volatile and insert save across calls
33 // If both above fail, spill.
35 //-----------------------------------------------------------------------------
36 void SparcV9IntRegClass::colorIGNode(IGNode * Node,
37 const std::vector<bool> &IsColorUsedArr) const
39 LiveRange *LR = Node->getParentLR();
42 std::cerr << "\nColoring LR [CallInt=" << LR->isCallInterference() <<"]:";
46 if (LR->hasSuggestedColor()) {
47 unsigned SugCol = LR->getSuggestedColor();
48 if (!IsColorUsedArr[SugCol]) {
49 if (LR->isSuggestedColorUsable()) {
50 // if the suggested color is volatile, we should use it only if
51 // there are no call interferences. Otherwise, it will get spilled.
53 std::cerr << "\n -Coloring with sug color: " << SugCol;
55 LR->setColor(LR->getSuggestedColor());
58 std::cerr << "\n Couldn't alloc Sug col - LR volatile & calls interf";
60 } else if (DEBUG_RA) { // can't allocate the suggested col
61 std::cerr << "\n Could NOT allocate the suggested color (already used) ";
62 printSet(*LR); std::cerr << "\n";
66 unsigned SearchStart; // start pos of color in pref-order
67 bool ColorFound= false; // have we found a color yet?
69 //if this Node is between calls
70 if (! LR->isCallInterference()) {
71 // start with volatiles (we can allocate volatiles safely)
72 SearchStart = SparcV9IntRegClass::StartOfAllRegs;
74 // start with non volatiles (no non-volatiles)
75 SearchStart = SparcV9IntRegClass::StartOfNonVolatileRegs;
78 unsigned c=0; // color
80 // find first unused color
81 for (c=SearchStart; c < SparcV9IntRegClass::NumOfAvailRegs; c++) {
82 if (!IsColorUsedArr[c]) {
89 LR->setColor(c); // first color found in preferred order
90 if (DEBUG_RA) std::cerr << "\n Colored after first search with col " << c;
93 // if color is not found because of call interference
94 // try even finding a volatile color and insert save across calls
96 else if (LR->isCallInterference()) {
97 // start from 0 - try to find even a volatile this time
98 SearchStart = SparcV9IntRegClass::StartOfAllRegs;
100 // find first unused volatile color
101 for(c=SearchStart; c < SparcV9IntRegClass::StartOfNonVolatileRegs; c++) {
102 if (! IsColorUsedArr[c]) {
110 // get the live range corresponding to live var
111 // since LR span across calls, must save across calls
113 LR->markForSaveAcrossCalls();
115 std::cerr << "\n Colored after SECOND search with col " << c;
120 // If we couldn't find a color regardless of call interference - i.e., we
121 // don't have either a volatile or non-volatile color left
124 LR->markForSpill(); // no color found - must spill
127 //-----------------------------------------------------------------------------
128 // Int CC Register Class - method for coloring a node in the interference graph.
132 // If (node has any interferences)
133 // /* all interference operations can use only one register! */
134 // mark the LR for spilling
136 // if (the LR is a 64-bit comparison) use %xcc
137 // else /*32-bit or smaller*/ use %icc
140 // Note: The third name (%ccr) is essentially an assembly mnemonic and
141 // depends solely on the opcode, so the name can be chosen in EmitAssembly.
142 //-----------------------------------------------------------------------------
143 void SparcV9IntCCRegClass::colorIGNode(IGNode *Node,
144 const std::vector<bool> &IsColorUsedArr) const
146 if (Node->getNumOfNeighbors() > 0)
147 Node->getParentLR()->markForSpill();
149 // Mark the appropriate register in any case (even if it needs to be spilled)
150 // because there is only one possible register, but more importantly, the
151 // spill algorithm cannot find it. In particular, we have to choose
152 // whether to use %xcc or %icc based on type of value compared
154 const LiveRange* ccLR = Node->getParentLR();
155 const Type* setCCType = (* ccLR->begin())->getType(); // any Value in LR
156 assert(setCCType->isIntegral() || isa<PointerType>(setCCType));
157 int ccReg = ((isa<PointerType>(setCCType) || setCCType == Type::LongTy)
161 // Let's just make sure values of two different types have not been
162 // coalesced into this LR.
163 for (ValueSet::const_iterator I=ccLR->begin(), E=ccLR->end(); I!=E; ++I) {
164 const Type* ccType = (*I)->getType();
165 assert((ccReg == xcc && (isa<PointerType>(ccType)
166 || ccType == Type::LongTy)) ||
167 (ccReg == icc && ccType->isIntegral() && ccType != Type::LongTy)
168 && "Comparisons needing different intCC regs coalesced in LR!");
172 Node->setColor(ccReg); // only one int cc reg is available
176 void SparcV9FloatCCRegClass::colorIGNode(IGNode *Node,
177 const std::vector<bool> &IsColorUsedArr) const {
178 for(unsigned c = 0; c != 4; ++c)
179 if (!IsColorUsedArr[c]) { // find unused color
184 Node->getParentLR()->markForSpill();
189 //-----------------------------------------------------------------------------
190 // Float Register Class - method for coloring a node in the interference graph.
194 // If the LR is a double try to allocate f32 - f63
195 // If the above fails or LR is single precision
196 // If the LR does not interfere with a call
197 // start allocating from f0
198 // Else start allocating from f6
199 // If a color is still not found because LR interferes with a call
200 // Search in f0 - f6. If found mark for spill across calls.
201 // If a color is still not fond, mark for spilling
203 //----------------------------------------------------------------------------
204 void SparcV9FloatRegClass::colorIGNode(IGNode * Node,
205 const std::vector<bool> &IsColorUsedArr) const
207 LiveRange *LR = Node->getParentLR();
210 // Check that the correct colors have been are marked for fp-doubles.
212 // FIXME: This is old code that is no longer needed. Temporarily converting
213 // it into a big assertion just to check that the replacement logic
214 // (invoking SparcV9FloatRegClass::markColorsUsed() directly from
215 // RegClass::colorIGNode) works correctly.
217 // In fact, this entire function should be identical to
218 // SparcV9IntRegClass::colorIGNode(), and perhaps can be
219 // made into a general case in CodeGen/RegAlloc/RegClass.cpp.
221 unsigned NumNeighbors = Node->getNumOfNeighbors(); // total # of neighbors
222 for(unsigned n=0; n < NumNeighbors; n++) { // for each neigh
223 IGNode *NeighIGNode = Node->getAdjIGNode(n);
224 LiveRange *NeighLR = NeighIGNode->getParentLR();
226 if (NeighLR->hasColor()) {
227 assert(IsColorUsedArr[ NeighLR->getColor() ]);
228 if (NeighLR->getType() == Type::DoubleTy)
229 assert(IsColorUsedArr[ NeighLR->getColor()+1 ]);
231 } else if (NeighLR->hasSuggestedColor() &&
232 NeighLR-> isSuggestedColorUsable() ) {
234 // if the neighbour can use the suggested color
235 assert(IsColorUsedArr[ NeighLR->getSuggestedColor() ]);
236 if (NeighLR->getType() == Type::DoubleTy)
237 assert(IsColorUsedArr[ NeighLR->getSuggestedColor()+1 ]);
242 // **NOTE: We don't check for call interferences in allocating suggested
243 // color in this class since ALL registers are volatile. If this fact
244 // changes, we should change the following part
245 //- see SparcV9IntRegClass::colorIGNode()
247 if( LR->hasSuggestedColor() ) {
248 if( ! IsColorUsedArr[ LR->getSuggestedColor() ] ) {
249 LR->setColor( LR->getSuggestedColor() );
251 } else if (DEBUG_RA) { // can't allocate the suggested col
252 std::cerr << " Could NOT allocate the suggested color for LR ";
253 printSet(*LR); std::cerr << "\n";
258 int ColorFound = -1; // have we found a color yet?
259 bool isCallInterf = LR->isCallInterference();
261 // if value is a double - search the double only region (f32 - f63)
262 // i.e. we try to allocate f32 - f63 first for doubles since singles
263 // cannot go there. By doing that, we provide more space for singles
266 if (LR->getType() == Type::DoubleTy)
267 ColorFound = findFloatColor( LR, 32, 64, IsColorUsedArr );
269 if (ColorFound >= 0) { // if we could find a color
270 LR->setColor(ColorFound);
274 // if we didn't find a color because the LR was single precision or
275 // all f32-f63 range is filled, we try to allocate a register from
276 // the f0 - f31 region
278 unsigned SearchStart; // start pos of color in pref-order
280 //if this Node is between calls (i.e., no call interferences )
281 if (! isCallInterf) {
282 // start with volatiles (we can allocate volatiles safely)
283 SearchStart = SparcV9FloatRegClass::StartOfAllRegs;
285 // start with non volatiles (no non-volatiles)
286 SearchStart = SparcV9FloatRegClass::StartOfNonVolatileRegs;
289 ColorFound = findFloatColor(LR, SearchStart, 32, IsColorUsedArr);
292 if (ColorFound >= 0) { // if we could find a color
293 LR->setColor(ColorFound);
295 } else if (isCallInterf) {
296 // We are here because there is a call interference and no non-volatile
297 // color could be found.
298 // Now try to allocate even a volatile color
299 ColorFound = findFloatColor(LR, SparcV9FloatRegClass::StartOfAllRegs,
300 SparcV9FloatRegClass::StartOfNonVolatileRegs,
304 if (ColorFound >= 0) {
305 LR->setColor(ColorFound); // first color found in preferred order
306 LR->markForSaveAcrossCalls();
308 // we are here because no color could be found
309 LR->markForSpill(); // no color found - must spill
313 //-----------------------------------------------------------------------------
314 // This method marks the registers used for a given register number.
315 // This marks a single register for Float regs, but the R,R+1 pair
316 // for double-precision registers.
317 //-----------------------------------------------------------------------------
319 void SparcV9FloatRegClass::markColorsUsed(unsigned RegInClass,
322 std::vector<bool> &IsColorUsedArr) const
324 if (UserRegType == SparcV9RegInfo::FPDoubleRegType ||
325 RegTypeWanted == SparcV9RegInfo::FPDoubleRegType) {
326 // This register is used as or is needed as a double-precision reg.
327 // We need to mark the [even,odd] pair corresponding to this reg.
328 // Get the even numbered register corresponding to this reg.
329 unsigned EvenRegInClass = RegInClass & ~1u;
330 assert(EvenRegInClass+1 < NumOfAllRegs &&
331 EvenRegInClass+1 < IsColorUsedArr.size());
332 IsColorUsedArr[EvenRegInClass] = true;
333 IsColorUsedArr[EvenRegInClass+1] = true;
336 assert(RegInClass < NumOfAllRegs && RegInClass < IsColorUsedArr.size());
337 assert(UserRegType == RegTypeWanted
338 && "Something other than FP single/double types share a reg class?");
339 IsColorUsedArr[RegInClass] = true;
343 // This method finds unused registers of the specified register type,
344 // using the given "used" flag array IsColorUsedArr. It checks a single
345 // entry in the array directly for float regs, and checks the pair [R,R+1]
346 // for double-precision registers
347 // It returns -1 if no unused color is found.
349 int SparcV9FloatRegClass::findUnusedColor(int RegTypeWanted,
350 const std::vector<bool> &IsColorUsedArr) const
352 if (RegTypeWanted == SparcV9RegInfo::FPDoubleRegType) {
353 unsigned NC = 2 * this->getNumOfAvailRegs();
354 assert(IsColorUsedArr.size() == NC && "Invalid colors-used array");
355 for (unsigned c = 0; c < NC; c+=2)
356 if (!IsColorUsedArr[c]) {
357 assert(!IsColorUsedArr[c+1] && "Incorrect used regs for FP double!");
363 return TargetRegClassInfo::findUnusedColor(RegTypeWanted, IsColorUsedArr);
366 //-----------------------------------------------------------------------------
367 // Helper method for coloring a node of Float Reg class.
368 // Finds the first available color in the range [Start,End] depending on the
369 // type of the Node (i.e., float/double)
370 //-----------------------------------------------------------------------------
372 int SparcV9FloatRegClass::findFloatColor(const LiveRange *LR,
375 const std::vector<bool> &IsColorUsedArr) const
377 if (LR->getType() == Type::DoubleTy) {
378 // find first unused color for a double
379 assert(Start % 2 == 0 && "Odd register number could be used for double!");
380 for (unsigned c=Start; c < End ; c+= 2)
381 if (!IsColorUsedArr[c]) {
382 assert(!IsColorUsedArr[c+1] &&
383 "Incorrect marking of used regs for SparcV9 FP double!");
387 // find first unused color for a single
388 for (unsigned c = Start; c < End; c++)
389 if (!IsColorUsedArr[c])
397 } // End llvm namespace