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// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#if V8_TARGET_ARCH_MIPS64
#include "src/codegen.h"
#include "src/ic/ic.h"
#include "src/ic/stub-cache.h"
#include "src/interface-descriptors.h"
namespace v8 {
namespace internal {
#define __ ACCESS_MASM(masm)
static void ProbeTable(StubCache* stub_cache, MacroAssembler* masm,
StubCache::Table table, Register receiver, Register name,
// The offset is scaled by 4, based on
// kCacheIndexShift, which is two bits
Register offset, Register scratch, Register scratch2,
Register offset_scratch) {
ExternalReference key_offset(stub_cache->key_reference(table));
ExternalReference value_offset(stub_cache->value_reference(table));
ExternalReference map_offset(stub_cache->map_reference(table));
uint64_t key_off_addr = reinterpret_cast<uint64_t>(key_offset.address());
uint64_t value_off_addr = reinterpret_cast<uint64_t>(value_offset.address());
uint64_t map_off_addr = reinterpret_cast<uint64_t>(map_offset.address());
// Check the relative positions of the address fields.
DCHECK(value_off_addr > key_off_addr);
DCHECK((value_off_addr - key_off_addr) % 4 == 0);
DCHECK((value_off_addr - key_off_addr) < (256 * 4));
DCHECK(map_off_addr > key_off_addr);
DCHECK((map_off_addr - key_off_addr) % 4 == 0);
DCHECK((map_off_addr - key_off_addr) < (256 * 4));
Label miss;
Register base_addr = scratch;
scratch = no_reg;
// Multiply by 3 because there are 3 fields per entry (name, code, map).
__ Dlsa(offset_scratch, offset, offset, 1);
// Calculate the base address of the entry.
__ li(base_addr, Operand(key_offset));
__ Dlsa(base_addr, base_addr, offset_scratch,
kPointerSizeLog2 - StubCache::kCacheIndexShift);
// Check that the key in the entry matches the name.
__ ld(at, MemOperand(base_addr, 0));
__ Branch(&miss, ne, name, Operand(at));
// Check the map matches.
__ ld(at, MemOperand(base_addr,
static_cast<int32_t>(map_off_addr - key_off_addr)));
__ ld(scratch2, FieldMemOperand(receiver, HeapObject::kMapOffset));
__ Branch(&miss, ne, at, Operand(scratch2));
// Get the code entry from the cache.
Register code = scratch2;
scratch2 = no_reg;
__ ld(code, MemOperand(base_addr,
static_cast<int32_t>(value_off_addr - key_off_addr)));
#ifdef DEBUG
if (FLAG_test_secondary_stub_cache && table == StubCache::kPrimary) {
__ jmp(&miss);
} else if (FLAG_test_primary_stub_cache && table == StubCache::kSecondary) {
__ jmp(&miss);
}
#endif
// Jump to the first instruction in the code stub.
__ Daddu(at, code, Operand(Code::kHeaderSize - kHeapObjectTag));
__ Jump(at);
// Miss: fall through.
__ bind(&miss);
}
void StubCache::GenerateProbe(MacroAssembler* masm, Register receiver,
Register name, Register scratch, Register extra,
Register extra2, Register extra3) {
Label miss;
// Make sure that code is valid. The multiplying code relies on the
// entry size being 12.
// DCHECK(sizeof(Entry) == 12);
// DCHECK(sizeof(Entry) == 3 * kPointerSize);
// Make sure that there are no register conflicts.
DCHECK(!AreAliased(receiver, name, scratch, extra, extra2, extra3));
// Check register validity.
DCHECK(!scratch.is(no_reg));
DCHECK(!extra.is(no_reg));
DCHECK(!extra2.is(no_reg));
DCHECK(!extra3.is(no_reg));
#ifdef DEBUG
// If vector-based ics are in use, ensure that scratch, extra, extra2 and
// extra3 don't conflict with the vector and slot registers, which need
// to be preserved for a handler call or miss.
if (IC::ICUseVector(ic_kind_)) {
Register vector, slot;
if (ic_kind_ == Code::STORE_IC || ic_kind_ == Code::KEYED_STORE_IC) {
vector = StoreWithVectorDescriptor::VectorRegister();
slot = StoreWithVectorDescriptor::SlotRegister();
} else {
DCHECK(ic_kind_ == Code::LOAD_IC || ic_kind_ == Code::KEYED_LOAD_IC);
vector = LoadWithVectorDescriptor::VectorRegister();
slot = LoadWithVectorDescriptor::SlotRegister();
}
DCHECK(!AreAliased(vector, slot, scratch, extra, extra2, extra3));
}
#endif
Counters* counters = masm->isolate()->counters();
__ IncrementCounter(counters->megamorphic_stub_cache_probes(), 1, extra2,
extra3);
// Check that the receiver isn't a smi.
__ JumpIfSmi(receiver, &miss);
// Get the map of the receiver and compute the hash.
__ lwu(scratch, FieldMemOperand(name, Name::kHashFieldOffset));
__ ld(at, FieldMemOperand(receiver, HeapObject::kMapOffset));
__ Addu(scratch, scratch, at);
__ Xor(scratch, scratch, Operand(kPrimaryMagic));
__ And(scratch, scratch,
Operand((kPrimaryTableSize - 1) << kCacheIndexShift));
// Probe the primary table.
ProbeTable(this, masm, kPrimary, receiver, name, scratch, extra, extra2,
extra3);
// Primary miss: Compute hash for secondary probe.
__ Subu(scratch, scratch, name);
__ Addu(scratch, scratch, kSecondaryMagic);
__ And(scratch, scratch,
Operand((kSecondaryTableSize - 1) << kCacheIndexShift));
// Probe the secondary table.
ProbeTable(this, masm, kSecondary, receiver, name, scratch, extra, extra2,
extra3);
// Cache miss: Fall-through and let caller handle the miss by
// entering the runtime system.
__ bind(&miss);
__ IncrementCounter(counters->megamorphic_stub_cache_misses(), 1, extra2,
extra3);
}
#undef __
} // namespace internal
} // namespace v8
#endif // V8_TARGET_ARCH_MIPS64
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