1/*
2 * Copyright (c) 2013, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23package org.graalvm.compiler.hotspot.sparc;
24
25import static jdk.vm.ci.code.ValueUtil.asRegister;
26import static jdk.vm.ci.code.ValueUtil.isRegister;
27import static jdk.vm.ci.sparc.SPARC.g0;
28import static jdk.vm.ci.sparc.SPARC.g5;
29import static jdk.vm.ci.sparc.SPARC.i0;
30import static jdk.vm.ci.sparc.SPARC.i7;
31import static jdk.vm.ci.sparc.SPARC.l0;
32import static jdk.vm.ci.sparc.SPARC.l7;
33import static jdk.vm.ci.sparc.SPARC.o0;
34import static jdk.vm.ci.sparc.SPARC.o7;
35import static jdk.vm.ci.sparc.SPARC.sp;
36import static org.graalvm.compiler.asm.sparc.SPARCAssembler.BPCC;
37import static org.graalvm.compiler.asm.sparc.SPARCAssembler.isGlobalRegister;
38import static org.graalvm.compiler.asm.sparc.SPARCAssembler.Annul.NOT_ANNUL;
39import static org.graalvm.compiler.asm.sparc.SPARCAssembler.BranchPredict.PREDICT_NOT_TAKEN;
40import static org.graalvm.compiler.asm.sparc.SPARCAssembler.CC.Xcc;
41import static org.graalvm.compiler.asm.sparc.SPARCAssembler.ConditionFlag.NotEqual;
42import static org.graalvm.compiler.core.common.GraalOptions.ZapStackOnMethodEntry;
43
44import java.util.ArrayList;
45import java.util.HashSet;
46import java.util.Set;
47import java.util.concurrent.ConcurrentHashMap;
48
49import org.graalvm.compiler.asm.Assembler;
50import org.graalvm.compiler.asm.Label;
51import org.graalvm.compiler.asm.sparc.SPARCAddress;
52import org.graalvm.compiler.asm.sparc.SPARCAssembler;
53import org.graalvm.compiler.asm.sparc.SPARCMacroAssembler;
54import org.graalvm.compiler.asm.sparc.SPARCMacroAssembler.ScratchRegister;
55import org.graalvm.compiler.code.CompilationResult;
56import org.graalvm.compiler.code.DataSection;
57import org.graalvm.compiler.code.DataSection.Data;
58import org.graalvm.compiler.core.common.CompilationIdentifier;
59import org.graalvm.compiler.core.common.alloc.RegisterAllocationConfig;
60import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
61import org.graalvm.compiler.core.sparc.SPARCNodeMatchRules;
62import org.graalvm.compiler.debug.CounterKey;
63import org.graalvm.compiler.debug.DebugContext;
64import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
65import org.graalvm.compiler.hotspot.HotSpotDataBuilder;
66import org.graalvm.compiler.hotspot.HotSpotGraalRuntimeProvider;
67import org.graalvm.compiler.hotspot.HotSpotHostBackend;
68import org.graalvm.compiler.hotspot.HotSpotLIRGenerationResult;
69import org.graalvm.compiler.hotspot.meta.HotSpotForeignCallsProvider;
70import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
71import org.graalvm.compiler.hotspot.stubs.Stub;
72import org.graalvm.compiler.lir.InstructionValueConsumer;
73import org.graalvm.compiler.lir.LIR;
74import org.graalvm.compiler.lir.LIRFrameState;
75import org.graalvm.compiler.lir.LIRInstruction;
76import org.graalvm.compiler.lir.StandardOp.SaveRegistersOp;
77import org.graalvm.compiler.lir.asm.CompilationResultBuilder;
78import org.graalvm.compiler.lir.asm.CompilationResultBuilderFactory;
79import org.graalvm.compiler.lir.asm.DataBuilder;
80import org.graalvm.compiler.lir.asm.FrameContext;
81import org.graalvm.compiler.lir.framemap.FrameMap;
82import org.graalvm.compiler.lir.framemap.FrameMapBuilder;
83import org.graalvm.compiler.lir.gen.LIRGenerationResult;
84import org.graalvm.compiler.lir.gen.LIRGeneratorTool;
85import org.graalvm.compiler.lir.sparc.SPARCCall;
86import org.graalvm.compiler.lir.sparc.SPARCDelayedControlTransfer;
87import org.graalvm.compiler.lir.sparc.SPARCFrameMap;
88import org.graalvm.compiler.lir.sparc.SPARCFrameMapBuilder;
89import org.graalvm.compiler.lir.sparc.SPARCLIRInstructionMixin;
90import org.graalvm.compiler.lir.sparc.SPARCLIRInstructionMixin.SizeEstimate;
91import org.graalvm.compiler.lir.sparc.SPARCTailDelayedLIRInstruction;
92import org.graalvm.compiler.nodes.StructuredGraph;
93import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;
94import org.graalvm.compiler.options.OptionValues;
95import org.graalvm.util.EconomicMap;
96import org.graalvm.util.EconomicSet;
97import org.graalvm.util.Equivalence;
98
99import jdk.vm.ci.code.CallingConvention;
100import jdk.vm.ci.code.Register;
101import jdk.vm.ci.code.RegisterConfig;
102import jdk.vm.ci.code.StackSlot;
103import jdk.vm.ci.hotspot.HotSpotCallingConventionType;
104import jdk.vm.ci.meta.JavaType;
105import jdk.vm.ci.meta.ResolvedJavaMethod;
106
107/**
108 * HotSpot SPARC specific backend.
109 */
110public class SPARCHotSpotBackend extends HotSpotHostBackend {
111
112    private static final SizeEstimateStatistics CONSTANT_ESTIMATED_STATS = new SizeEstimateStatistics("ESTIMATE");
113    private static final SizeEstimateStatistics CONSTANT_ACTUAL_STATS = new SizeEstimateStatistics("ACTUAL");
114
115    public SPARCHotSpotBackend(GraalHotSpotVMConfig config, HotSpotGraalRuntimeProvider runtime, HotSpotProviders providers) {
116        super(config, runtime, providers);
117    }
118
119    private static class SizeEstimateStatistics {
120        private static final ConcurrentHashMap<String, CounterKey> counters = new ConcurrentHashMap<>();
121        private final String suffix;
122
123        SizeEstimateStatistics(String suffix) {
124            super();
125            this.suffix = suffix;
126        }
127
128        public void add(Class<?> c, int count, DebugContext debug) {
129            String name = SizeEstimateStatistics.class.getSimpleName() + "_" + c.getSimpleName() + "." + suffix;
130            CounterKey m = counters.computeIfAbsent(name, (n) -> DebugContext.counter(n));
131            m.add(debug, count);
132        }
133    }
134
135    @Override
136    public FrameMapBuilder newFrameMapBuilder(RegisterConfig registerConfig) {
137        RegisterConfig registerConfigNonNull = registerConfig == null ? getCodeCache().getRegisterConfig() : registerConfig;
138        return new SPARCFrameMapBuilder(newFrameMap(registerConfigNonNull), getCodeCache(), registerConfigNonNull);
139    }
140
141    @Override
142    public FrameMap newFrameMap(RegisterConfig registerConfig) {
143        return new SPARCFrameMap(getCodeCache(), registerConfig, this);
144    }
145
146    @Override
147    public LIRGeneratorTool newLIRGenerator(LIRGenerationResult lirGenRes) {
148        return new SPARCHotSpotLIRGenerator(getProviders(), getRuntime().getVMConfig(), lirGenRes);
149    }
150
151    @Override
152    public LIRGenerationResult newLIRGenerationResult(CompilationIdentifier compilationId, LIR lir, FrameMapBuilder frameMapBuilder, StructuredGraph graph, Object stub) {
153        return new HotSpotLIRGenerationResult(compilationId, lir, frameMapBuilder, makeCallingConvention(graph, (Stub) stub), stub);
154    }
155
156    @Override
157    public NodeLIRBuilderTool newNodeLIRBuilder(StructuredGraph graph, LIRGeneratorTool lirGen) {
158        return new SPARCHotSpotNodeLIRBuilder(graph, lirGen, new SPARCNodeMatchRules(lirGen));
159    }
160
161    @Override
162    protected void bangStackWithOffset(CompilationResultBuilder crb, int bangOffset) {
163        // Use SPARCAddress to get the final displacement including the stack bias.
164        SPARCMacroAssembler masm = (SPARCMacroAssembler) crb.asm;
165        SPARCAddress address = new SPARCAddress(sp, -bangOffset);
166        if (SPARCAssembler.isSimm13(address.getDisplacement())) {
167            masm.stx(g0, address);
168        } else {
169            try (ScratchRegister sc = masm.getScratchRegister()) {
170                Register scratch = sc.getRegister();
171                assert isGlobalRegister(scratch) : "Only global (g1-g7) registers are allowed if the frame was not initialized here. Got register " + scratch;
172                masm.setx(address.getDisplacement(), scratch, false);
173                masm.stx(g0, new SPARCAddress(sp, scratch));
174            }
175        }
176    }
177
178    public class HotSpotFrameContext implements FrameContext {
179
180        final boolean isStub;
181
182        HotSpotFrameContext(boolean isStub) {
183            this.isStub = isStub;
184        }
185
186        @Override
187        public boolean hasFrame() {
188            return true;
189        }
190
191        @Override
192        public void enter(CompilationResultBuilder crb) {
193            final int frameSize = crb.frameMap.totalFrameSize();
194            final int stackpoinerChange = -frameSize;
195            SPARCMacroAssembler masm = (SPARCMacroAssembler) crb.asm;
196            emitStackOverflowCheck(crb);
197
198            if (SPARCAssembler.isSimm13(stackpoinerChange)) {
199                masm.save(sp, stackpoinerChange, sp);
200            } else {
201                try (ScratchRegister sc = masm.getScratchRegister()) {
202                    Register scratch = sc.getRegister();
203                    assert isGlobalRegister(scratch) : "Only global registers are allowed before save. Got register " + scratch;
204                    masm.setx(stackpoinerChange, scratch, false);
205                    masm.save(sp, scratch, sp);
206                }
207            }
208
209            if (ZapStackOnMethodEntry.getValue(crb.getOptions())) {
210                final int slotSize = 8;
211                for (int i = 0; i < frameSize / slotSize; ++i) {
212                    // 0xC1C1C1C1
213                    masm.stx(g0, new SPARCAddress(sp, i * slotSize));
214                }
215            }
216        }
217
218        @Override
219        public void leave(CompilationResultBuilder crb) {
220            SPARCMacroAssembler masm = (SPARCMacroAssembler) crb.asm;
221            masm.restoreWindow();
222        }
223    }
224
225    @Override
226    protected Assembler createAssembler(FrameMap frameMap) {
227        return new SPARCMacroAssembler(getTarget());
228    }
229
230    @Override
231    public CompilationResultBuilder newCompilationResultBuilder(LIRGenerationResult lirGenRes, FrameMap frameMap, CompilationResult compilationResult, CompilationResultBuilderFactory factory) {
232        HotSpotLIRGenerationResult gen = (HotSpotLIRGenerationResult) lirGenRes;
233        LIR lir = gen.getLIR();
234        assert gen.getDeoptimizationRescueSlot() == null || frameMap.frameNeedsAllocating() : "method that can deoptimize must have a frame";
235
236        Stub stub = gen.getStub();
237        Assembler masm = createAssembler(frameMap);
238        // On SPARC we always use stack frames.
239        HotSpotFrameContext frameContext = new HotSpotFrameContext(stub != null);
240        DataBuilder dataBuilder = new HotSpotDataBuilder(getCodeCache().getTarget());
241        OptionValues options = lir.getOptions();
242        DebugContext debug = lir.getDebug();
243        CompilationResultBuilder crb = factory.createBuilder(getProviders().getCodeCache(), getProviders().getForeignCalls(), frameMap, masm, dataBuilder, frameContext, options, debug,
244                        compilationResult);
245        crb.setTotalFrameSize(frameMap.totalFrameSize());
246        crb.setMaxInterpreterFrameSize(gen.getMaxInterpreterFrameSize());
247        StackSlot deoptimizationRescueSlot = gen.getDeoptimizationRescueSlot();
248        if (deoptimizationRescueSlot != null && stub == null) {
249            crb.compilationResult.setCustomStackAreaOffset(deoptimizationRescueSlot);
250        }
251
252        if (stub != null) {
253            // Even on sparc we need to save floating point registers
254            EconomicSet<Register> destroyedCallerRegisters = gatherDestroyedCallerRegisters(lir);
255            EconomicMap<LIRFrameState, SaveRegistersOp> calleeSaveInfo = gen.getCalleeSaveInfo();
256            updateStub(stub, destroyedCallerRegisters, calleeSaveInfo, frameMap);
257        }
258        assert registerSizePredictionValidator(crb, debug);
259        return crb;
260    }
261
262    /**
263     * Registers a verifier which checks if the LIRInstructions estimate of constants size is
264     * greater or equal to the actual one.
265     */
266    private static boolean registerSizePredictionValidator(final CompilationResultBuilder crb, DebugContext debug) {
267        /**
268         * Used to hold state between beforeOp and afterOp
269         */
270        class ValidationState {
271            LIRInstruction op;
272            final DebugContext debug;
273            int constantSizeBefore;
274
275            ValidationState(DebugContext debug) {
276                this.debug = debug;
277            }
278
279            public void before(LIRInstruction before) {
280                assert op == null : "LIRInstruction " + op + " no after call received";
281                op = before;
282                constantSizeBefore = calculateDataSectionSize(crb.compilationResult.getDataSection());
283            }
284
285            public void after(LIRInstruction after) {
286                assert after.equals(op) : "Instructions before/after don't match " + op + "/" + after;
287                int constantSizeAfter = calculateDataSectionSize(crb.compilationResult.getDataSection());
288                int actual = constantSizeAfter - constantSizeBefore;
289                if (op instanceof SPARCLIRInstructionMixin) {
290                    org.graalvm.compiler.lir.sparc.SPARCLIRInstructionMixin.SizeEstimate size = ((SPARCLIRInstructionMixin) op).estimateSize();
291                    assert size != null : "No size prediction available for op: " + op;
292                    Class<?> c = op.getClass();
293                    CONSTANT_ESTIMATED_STATS.add(c, size.constantSize, debug);
294                    CONSTANT_ACTUAL_STATS.add(c, actual, debug);
295                    assert size.constantSize >= actual : "Op " + op + " exceeded estimated constant size; predicted: " + size.constantSize + " actual: " + actual;
296                } else {
297                    assert actual == 0 : "Op " + op + " emitted to DataSection without any estimate.";
298                }
299                op = null;
300                constantSizeBefore = 0;
301            }
302        }
303        final ValidationState state = new ValidationState(debug);
304        crb.setOpCallback(op -> state.before(op), op -> state.after(op));
305        return true;
306    }
307
308    private static int calculateDataSectionSize(DataSection ds) {
309        int sum = 0;
310        for (Data d : ds) {
311            sum += d.getSize();
312        }
313        return sum;
314    }
315
316    @Override
317    public void emitCode(CompilationResultBuilder crb, LIR lir, ResolvedJavaMethod installedCodeOwner) {
318        SPARCMacroAssembler masm = (SPARCMacroAssembler) crb.asm;
319        // TODO: (sa) Fold the two traversals into one
320        stuffDelayedControlTransfers(lir);
321        int constantSize = calculateConstantSize(lir);
322        boolean canUseImmediateConstantLoad = constantSize < (1 << 13);
323        masm.setImmediateConstantLoad(canUseImmediateConstantLoad);
324        FrameMap frameMap = crb.frameMap;
325        RegisterConfig regConfig = frameMap.getRegisterConfig();
326        Label unverifiedStub = installedCodeOwner == null || installedCodeOwner.isStatic() ? null : new Label();
327        for (int i = 0; i < 2; i++) {
328            if (i > 0) {
329                crb.resetForEmittingCode();
330                lir.resetLabels();
331                resetDelayedControlTransfers(lir);
332            }
333
334            // Emit the prefix
335            if (unverifiedStub != null) {
336                crb.recordMark(config.MARKID_UNVERIFIED_ENTRY);
337                // We need to use JavaCall here because we haven't entered the frame yet.
338                CallingConvention cc = regConfig.getCallingConvention(HotSpotCallingConventionType.JavaCall, null, new JavaType[]{getProviders().getMetaAccess().lookupJavaType(Object.class)}, this);
339                Register inlineCacheKlass = g5; // see MacroAssembler::ic_call
340
341                try (ScratchRegister sc = masm.getScratchRegister()) {
342                    Register scratch = sc.getRegister();
343                    Register receiver = asRegister(cc.getArgument(0));
344                    SPARCAddress src = new SPARCAddress(receiver, config.hubOffset);
345
346                    masm.ldx(src, scratch);
347                    masm.cmp(scratch, inlineCacheKlass);
348                }
349                BPCC.emit(masm, Xcc, NotEqual, NOT_ANNUL, PREDICT_NOT_TAKEN, unverifiedStub);
350                masm.nop();  // delay slot
351            }
352
353            masm.align(config.codeEntryAlignment);
354            crb.recordMark(config.MARKID_OSR_ENTRY);
355            crb.recordMark(config.MARKID_VERIFIED_ENTRY);
356
357            // Emit code for the LIR
358            crb.emit(lir);
359        }
360        profileInstructions(lir, crb);
361
362        HotSpotFrameContext frameContext = (HotSpotFrameContext) crb.frameContext;
363        HotSpotForeignCallsProvider foreignCalls = getProviders().getForeignCalls();
364        if (!frameContext.isStub) {
365            crb.recordMark(config.MARKID_EXCEPTION_HANDLER_ENTRY);
366            SPARCCall.directCall(crb, masm, foreignCalls.lookupForeignCall(EXCEPTION_HANDLER), null, null);
367            crb.recordMark(config.MARKID_DEOPT_HANDLER_ENTRY);
368            SPARCCall.directCall(crb, masm, foreignCalls.lookupForeignCall(DEOPTIMIZATION_HANDLER), null, null);
369        } else {
370            // No need to emit the stubs for entries back into the method since
371            // it has no calls that can cause such "return" entries
372        }
373
374        if (unverifiedStub != null) {
375            masm.bind(unverifiedStub);
376            try (ScratchRegister sc = masm.getScratchRegister()) {
377                Register scratch = sc.getRegister();
378                SPARCCall.indirectJmp(crb, masm, scratch, foreignCalls.lookupForeignCall(IC_MISS_HANDLER));
379            }
380        }
381        masm.peephole();
382    }
383
384    private static int calculateConstantSize(LIR lir) {
385        int size = 0;
386        for (AbstractBlockBase<?> block : lir.codeEmittingOrder()) {
387            if (block == null) {
388                continue;
389            }
390            for (LIRInstruction inst : lir.getLIRforBlock(block)) {
391                if (inst instanceof SPARCLIRInstructionMixin) {
392                    SizeEstimate pred = ((SPARCLIRInstructionMixin) inst).estimateSize();
393                    if (pred != null) {
394                        size += pred.constantSize;
395                    }
396                }
397            }
398        }
399        return size;
400    }
401
402    private static void resetDelayedControlTransfers(LIR lir) {
403        for (AbstractBlockBase<?> block : lir.codeEmittingOrder()) {
404            if (block == null) {
405                continue;
406            }
407            for (LIRInstruction inst : lir.getLIRforBlock(block)) {
408                if (inst instanceof SPARCDelayedControlTransfer) {
409                    ((SPARCDelayedControlTransfer) inst).resetState();
410                }
411            }
412        }
413    }
414
415    /**
416     * Fix-up over whole LIR.
417     *
418     * @see #stuffDelayedControlTransfers(LIR, AbstractBlockBase)
419     * @param l
420     */
421    private static void stuffDelayedControlTransfers(LIR l) {
422        for (AbstractBlockBase<?> b : l.codeEmittingOrder()) {
423            if (b != null) {
424                stuffDelayedControlTransfers(l, b);
425            }
426        }
427    }
428
429    /**
430     * Tries to put DelayedControlTransfer instructions and DelayableLIRInstructions together. Also
431     * it tries to move the DelayedLIRInstruction to the DelayedControlTransfer instruction, if
432     * possible.
433     */
434    private static void stuffDelayedControlTransfers(LIR l, AbstractBlockBase<?> block) {
435        ArrayList<LIRInstruction> instructions = l.getLIRforBlock(block);
436        if (instructions.size() >= 2) {
437            LIRDependencyAccumulator acc = new LIRDependencyAccumulator();
438            SPARCDelayedControlTransfer delayedTransfer = null;
439            int delayTransferPosition = -1;
440            for (int i = instructions.size() - 1; i >= 0; i--) {
441                LIRInstruction inst = instructions.get(i);
442                boolean adjacent = delayTransferPosition - i == 1;
443                if (!adjacent || inst.destroysCallerSavedRegisters() || leavesRegisterWindow(inst)) {
444                    delayedTransfer = null;
445                }
446                if (inst instanceof SPARCDelayedControlTransfer) {
447                    delayedTransfer = (SPARCDelayedControlTransfer) inst;
448                    acc.start(inst);
449                    delayTransferPosition = i;
450                } else if (delayedTransfer != null) {
451                    boolean overlap = acc.add(inst);
452                    if (!overlap && inst instanceof SPARCTailDelayedLIRInstruction) {
453                        // We have found a non overlapping LIR instruction which can be delayed
454                        ((SPARCTailDelayedLIRInstruction) inst).setDelayedControlTransfer(delayedTransfer);
455                        delayedTransfer = null;
456                    }
457                }
458            }
459        }
460    }
461
462    private static boolean leavesRegisterWindow(LIRInstruction inst) {
463        return inst instanceof SPARCLIRInstructionMixin && ((SPARCLIRInstructionMixin) inst).leavesRegisterWindow();
464    }
465
466    /**
467     * Accumulates inputs/outputs/temp/alive in a set along we walk back the LIRInstructions and
468     * detects, if there is any overlap. In this way LIRInstructions can be detected, which can be
469     * moved nearer to the DelayedControlTransfer instruction.
470     */
471    private static class LIRDependencyAccumulator {
472        private final Set<Object> inputs = new HashSet<>(10);
473        private boolean overlap = false;
474
475        private final InstructionValueConsumer valueConsumer = (instruction, value, mode, flags) -> {
476            Object valueObject = value;
477            if (isRegister(value)) { // Canonicalize registers
478                valueObject = asRegister(value);
479            }
480            if (!inputs.add(valueObject)) {
481                overlap = true;
482            }
483        };
484
485        public void start(LIRInstruction initial) {
486            inputs.clear();
487            overlap = false;
488            initial.visitEachInput(valueConsumer);
489            initial.visitEachTemp(valueConsumer);
490            initial.visitEachAlive(valueConsumer);
491        }
492
493        /**
494         * Adds the inputs of lir instruction to the accumulator and returns, true if there was any
495         * overlap of parameters.
496         *
497         * @param inst
498         * @return true if an overlap was found
499         */
500        public boolean add(LIRInstruction inst) {
501            overlap = false;
502            inst.visitEachOutput(valueConsumer);
503            inst.visitEachTemp(valueConsumer);
504            inst.visitEachInput(valueConsumer);
505            inst.visitEachAlive(valueConsumer);
506            return overlap;
507        }
508    }
509
510    @Override
511    public RegisterAllocationConfig newRegisterAllocationConfig(RegisterConfig registerConfig, String[] allocationRestrictedTo) {
512        RegisterConfig registerConfigNonNull = registerConfig == null ? getCodeCache().getRegisterConfig() : registerConfig;
513        return new SPARCHotSpotRegisterAllocationConfig(registerConfigNonNull, allocationRestrictedTo);
514    }
515
516    @Override
517    public EconomicSet<Register> translateToCallerRegisters(EconomicSet<Register> calleeRegisters) {
518        EconomicSet<Register> callerRegisters = EconomicSet.create(Equivalence.IDENTITY, calleeRegisters.size());
519        for (Register register : calleeRegisters) {
520            if (l0.number <= register.number && register.number <= l7.number) {
521                // do nothing
522            } else if (o0.number <= register.number && register.number <= o7.number) {
523                // do nothing
524            } else if (i0.number <= register.number && register.number <= i7.number) {
525                // translate input to output registers
526                callerRegisters.add(translateInputToOutputRegister(register));
527            } else {
528                callerRegisters.add(register);
529            }
530        }
531        return callerRegisters;
532    }
533
534    private Register translateInputToOutputRegister(Register register) {
535        assert i0.number <= register.number && register.number <= i7.number : "Not an input register " + register;
536        return getTarget().arch.getRegisters().get(o0.number + register.number - i0.number);
537    }
538}
539