Setup policies for register allocation.
Change-Id: I857e77530fca3e2fb872fc142a916af1b48400dc
diff --git a/compiler/optimizing/code_generator.h b/compiler/optimizing/code_generator.h
index 54f9e70..74cbccc 100644
--- a/compiler/optimizing/code_generator.h
+++ b/compiler/optimizing/code_generator.h
@@ -62,6 +62,12 @@
// bits are in a stack slot. The kQuickParameter kind is for
// handling this special case.
kQuickParameter = 4,
+
+ // Unallocated location represents a location that is not fixed and can be
+ // allocated by a register allocator. Each unallocated location has
+ // a policy that specifies what kind of location is suitable. Payload
+ // contains register allocation policy.
+ kUnallocated = 5,
};
Location() : value_(kInvalid) {
@@ -166,10 +172,50 @@
case kStackSlot: return "S";
case kDoubleStackSlot: return "DS";
case kQuickParameter: return "Q";
+ case kUnallocated: return "U";
}
return "?";
}
+ // Unallocated locations.
+ enum Policy {
+ kAny,
+ kRequiresRegister,
+ kSameAsFirstInput,
+ };
+
+ bool IsUnallocated() const {
+ return GetKind() == kUnallocated;
+ }
+
+ static Location UnallocatedLocation(Policy policy) {
+ return Location(kUnallocated, PolicyField::Encode(policy));
+ }
+
+ // Any free register is suitable to replace this unallocated location.
+ static Location Any() {
+ return UnallocatedLocation(kAny);
+ }
+
+ static Location RequiresRegister() {
+ return UnallocatedLocation(kRequiresRegister);
+ }
+
+ // The location of the first input to the instruction will be
+ // used to replace this unallocated location.
+ static Location SameAsFirstInput() {
+ return UnallocatedLocation(kSameAsFirstInput);
+ }
+
+ Policy GetPolicy() const {
+ DCHECK(IsUnallocated());
+ return PolicyField::Decode(GetPayload());
+ }
+
+ uword GetEncoding() const {
+ return GetPayload();
+ }
+
private:
// Number of bits required to encode Kind value.
static constexpr uint32_t kBitsForKind = 4;
@@ -187,6 +233,9 @@
typedef BitField<Kind, 0, kBitsForKind> KindField;
typedef BitField<uword, kBitsForKind, kBitsForPayload> PayloadField;
+ // Layout for kUnallocated locations payload.
+ typedef BitField<Policy, 0, 3> PolicyField;
+
// Layout for stack slots.
static const intptr_t kStackIndexBias =
static_cast<intptr_t>(1) << (kBitsForPayload - 1);
@@ -208,40 +257,52 @@
class LocationSummary : public ArenaObject {
public:
explicit LocationSummary(HInstruction* instruction)
- : inputs(instruction->GetBlock()->GetGraph()->GetArena(), instruction->InputCount()),
- temps(instruction->GetBlock()->GetGraph()->GetArena(), 0) {
- inputs.SetSize(instruction->InputCount());
+ : inputs_(instruction->GetBlock()->GetGraph()->GetArena(), instruction->InputCount()),
+ temps_(instruction->GetBlock()->GetGraph()->GetArena(), 0) {
+ inputs_.SetSize(instruction->InputCount());
for (size_t i = 0; i < instruction->InputCount(); i++) {
- inputs.Put(i, Location());
+ inputs_.Put(i, Location());
}
}
void SetInAt(uint32_t at, Location location) {
- inputs.Put(at, location);
+ inputs_.Put(at, location);
}
Location InAt(uint32_t at) const {
- return inputs.Get(at);
+ return inputs_.Get(at);
+ }
+
+ size_t GetInputCount() const {
+ return inputs_.Size();
}
void SetOut(Location location) {
- output = Location(location);
+ output_ = Location(location);
}
void AddTemp(Location location) {
- temps.Add(location);
+ temps_.Add(location);
}
Location GetTemp(uint32_t at) const {
- return temps.Get(at);
+ return temps_.Get(at);
}
- Location Out() const { return output; }
+ void SetTempAt(uint32_t at, Location location) {
+ temps_.Put(at, location);
+ }
+
+ size_t GetTempCount() const {
+ return temps_.Size();
+ }
+
+ Location Out() const { return output_; }
private:
- GrowableArray<Location> inputs;
- GrowableArray<Location> temps;
- Location output;
+ GrowableArray<Location> inputs_;
+ GrowableArray<Location> temps_;
+ Location output_;
DISALLOW_COPY_AND_ASSIGN(LocationSummary);
};
@@ -286,15 +347,33 @@
std::vector<uint8_t>* vector, const DexCompilationUnit& dex_compilation_unit) const;
protected:
- explicit CodeGenerator(HGraph* graph)
+ CodeGenerator(HGraph* graph, size_t number_of_registers)
: frame_size_(0),
graph_(graph),
block_labels_(graph->GetArena(), 0),
- pc_infos_(graph->GetArena(), 32) {
+ pc_infos_(graph->GetArena(), 32),
+ blocked_registers_(static_cast<bool*>(
+ graph->GetArena()->Alloc(number_of_registers * sizeof(bool), kArenaAllocData))) {
block_labels_.SetSize(graph->GetBlocks()->Size());
}
~CodeGenerator() { }
+ // Register allocation logic.
+ void AllocateRegistersLocally(HInstruction* instruction) const;
+
+ // Backend specific implementation for allocating a register.
+ virtual ManagedRegister AllocateFreeRegister(Primitive::Type type,
+ bool* blocked_registers) const = 0;
+
+ // Raw implementation of allocating a register: loops over blocked_registers to find
+ // the first available register.
+ size_t AllocateFreeRegisterInternal(bool* blocked_registers, size_t number_of_registers) const;
+
+ virtual void SetupBlockedRegisters(bool* blocked_registers) const = 0;
+ virtual size_t GetNumberOfRegisters() const = 0;
+
+ virtual Location GetStackLocation(HLoadLocal* load) const = 0;
+
// Frame size required for this method.
uint32_t frame_size_;
uint32_t core_spill_mask_;
@@ -309,6 +388,9 @@
GrowableArray<Label> block_labels_;
GrowableArray<PcInfo> pc_infos_;
+ // Temporary data structure used when doing register allocation.
+ bool* const blocked_registers_;
+
DISALLOW_COPY_AND_ASSIGN(CodeGenerator);
};