Embedded constant pools.

src/ppc/assembler-ppc-inl.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 76 matching lines @@
 Address RelocInfo::target_address() {
   DCHECK(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_));
   return Assembler::target_address_at(pc_, host_);
 }
 
 
 Address RelocInfo::target_address_address() {
   DCHECK(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_) ||
          rmode_ == EMBEDDED_OBJECT || rmode_ == EXTERNAL_REFERENCE);
 
+  if (FLAG_enable_embedded_constant_pool &&
+      Assembler::IsConstantPoolLoadStart(pc_)) {
+    // We return the PC for ool constant pool since this function is used by the
+    // serializer and expects the address to reside within the code object.
+    return reinterpret_cast<Address>(pc_);
+  }
+
   // Read the address of the word containing the target_address in an
   // instruction stream.
   // The only architecture-independent user of this function is the serializer.
   // The serializer uses it to find out how many raw bytes of instruction to
   // output before the next target.
   // For an instruction like LIS/ORI where the target bits are mixed into the
   // instruction bits, the size of the target will be zero, indicating that the
   // serializer should not step forward in memory after a target is resolved
   // and written.
   return reinterpret_cast<Address>(pc_);
 }
 
 
 Address RelocInfo::constant_pool_entry_address() {
+  if (FLAG_enable_embedded_constant_pool) {
+    Address constant_pool = host_->constant_pool();
+    DCHECK(constant_pool);
+    ConstantPoolEntry::Access access;
+    if (Assembler::IsConstantPoolLoadStart(pc_, &access))
+      return Assembler::target_constant_pool_address_at(
+          pc_, constant_pool, access, ConstantPoolEntry::INTPTR);
+  }
   UNREACHABLE();
   return NULL;
 }
 
 
 int RelocInfo::target_address_size() { return Assembler::kSpecialTargetSize; }
 
 
 void RelocInfo::set_target_address(Address target,
                                    WriteBarrierMode write_barrier_mode,
@@ skipping 15 matching lines @@
 
 
 Address Assembler::target_address_from_return_address(Address pc) {
 // Returns the address of the call target from the return address that will
 // be returned to after a call.
 // Call sequence is :
 //  mov   ip, @ call address
 //  mtlr  ip
 //  blrl
 //                      @ return address
-  return pc - (kMovInstructions + 2) * kInstrSize;
+  int len;
+  ConstantPoolEntry::Access access;
+  if (FLAG_enable_embedded_constant_pool &&
+      IsConstantPoolLoadEnd(pc - 3 * kInstrSize, &access)) {
+    len = (access == ConstantPoolEntry::OVERFLOWED) ? 2 : 1;
+  } else {
+    len = kMovInstructionsNoConstantPool;
+  }
+  return pc - (len + 2) * kInstrSize;
 }
 
 
 Address Assembler::return_address_from_call_start(Address pc) {
-  return pc + (kMovInstructions + 2) * kInstrSize;
+  int len;
+  ConstantPoolEntry::Access access;
+  if (FLAG_enable_embedded_constant_pool &&
+      IsConstantPoolLoadStart(pc, &access)) {
+    len = (access == ConstantPoolEntry::OVERFLOWED) ? 2 : 1;
+  } else {
+    len = kMovInstructionsNoConstantPool;
+  }
+  return pc + (len + 2) * kInstrSize;
 }
 
 
 Object* RelocInfo::target_object() {
   DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
   return reinterpret_cast<Object*>(Assembler::target_address_at(pc_, host_));
 }
 
 
 Handle<Object> RelocInfo::target_object_handle(Assembler* origin) {
@@ skipping 57 matching lines @@
   Address address = cell->address() + Cell::kValueOffset;
   Memory::Address_at(pc_) = address;
   if (write_barrier_mode == UPDATE_WRITE_BARRIER && host() != NULL) {
     // TODO(1550) We are passing NULL as a slot because cell can never be on
     // evacuation candidate.
     host()->GetHeap()->incremental_marking()->RecordWrite(host(), NULL, cell);
   }
 }
 
 
-static const int kNoCodeAgeInstructions = 6;
-static const int kCodeAgingInstructions = Assembler::kMovInstructions + 3;
+static const int kNoCodeAgeInstructions =
+    FLAG_enable_embedded_constant_pool ? 7 : 6;
+static const int kCodeAgingInstructions =
+    Assembler::kMovInstructionsNoConstantPool + 3;
 static const int kNoCodeAgeSequenceInstructions =
     ((kNoCodeAgeInstructions >= kCodeAgingInstructions)
          ? kNoCodeAgeInstructions
          : kCodeAgingInstructions);
 static const int kNoCodeAgeSequenceNops =
     (kNoCodeAgeSequenceInstructions - kNoCodeAgeInstructions);
 static const int kCodeAgingSequenceNops =
     (kNoCodeAgeSequenceInstructions - kCodeAgingInstructions);
 static const int kCodeAgingTargetDelta = 1 * Assembler::kInstrSize;
 static const int kNoCodeAgeSequenceLength =
@@ skipping 200 matching lines @@
   CheckBuffer();
   *reinterpret_cast<Instr*>(pc_) = x;
   pc_ += kInstrSize;
   CheckTrampolinePoolQuick();
 }
 
 bool Operand::is_reg() const { return rm_.is_valid(); }
 
 
 // Fetch the 32bit value from the FIXED_SEQUENCE lis/ori
-Address Assembler::target_address_at(Address pc,
-                                     ConstantPoolArray* constant_pool) {
+Address Assembler::target_address_at(Address pc, Address constant_pool) {
+  if (FLAG_enable_embedded_constant_pool && constant_pool) {
+    ConstantPoolEntry::Access access;
+    if (IsConstantPoolLoadStart(pc, &access))
+      return Memory::Address_at(target_constant_pool_address_at(
+          pc, constant_pool, access, ConstantPoolEntry::INTPTR));
+  }
+
   Instr instr1 = instr_at(pc);
   Instr instr2 = instr_at(pc + kInstrSize);
   // Interpret 2 instructions generated by lis/ori
   if (IsLis(instr1) && IsOri(instr2)) {
 #if V8_TARGET_ARCH_PPC64
     Instr instr4 = instr_at(pc + (3 * kInstrSize));
     Instr instr5 = instr_at(pc + (4 * kInstrSize));
     // Assemble the 64 bit value.
     uint64_t hi = (static_cast<uint32_t>((instr1 & kImm16Mask) << 16) |
                    static_cast<uint32_t>(instr2 & kImm16Mask));
     uint64_t lo = (static_cast<uint32_t>((instr4 & kImm16Mask) << 16) |
                    static_cast<uint32_t>(instr5 & kImm16Mask));
     return reinterpret_cast<Address>((hi << 32) | lo);
 #else
     // Assemble the 32 bit value.
     return reinterpret_cast<Address>(((instr1 & kImm16Mask) << 16) |
                                      (instr2 & kImm16Mask));
 #endif
   }
 
   UNREACHABLE();
   return NULL;
 }
 
 
+#if V8_TARGET_ARCH_PPC64
+const int kLoadIntptrOpcode = LD;
+#else
+const int kLoadIntptrOpcode = LWZ;
+#endif
+
+// Constant pool load sequence detection:
+// 1) REGULAR access:
+//    load <dst>, kConstantPoolRegister + <offset>
+//
+// 2) OVERFLOWED access:
+//    addis <scratch>, kConstantPoolRegister, <offset_high>
+//    load <dst>, <scratch> + <offset_low>
+bool Assembler::IsConstantPoolLoadStart(Address pc,
+                                        ConstantPoolEntry::Access* access) {
+  Instr instr = instr_at(pc);
+  int opcode = instr & kOpcodeMask;
+  if (!GetRA(instr).is(kConstantPoolRegister)) return false;
+  bool overflowed = (opcode == ADDIS);
+#ifdef DEBUG
+  if (overflowed) {
+    opcode = instr_at(pc + kInstrSize) & kOpcodeMask;
+  }
+  DCHECK(opcode == kLoadIntptrOpcode || opcode == LFD);
+#endif
+  if (access) {
+    *access = (overflowed ? ConstantPoolEntry::OVERFLOWED
+                          : ConstantPoolEntry::REGULAR);
+  }
+  return true;
+}
+
+
+bool Assembler::IsConstantPoolLoadEnd(Address pc,
+                                      ConstantPoolEntry::Access* access) {
+  Instr instr = instr_at(pc);
+  int opcode = instr & kOpcodeMask;
+  if (!(opcode == kLoadIntptrOpcode || opcode == LFD)) return false;
+  bool overflowed = !GetRA(instr).is(kConstantPoolRegister);
+#ifdef DEBUG
+  if (overflowed) {
+    instr = instr_at(pc - kInstrSize);
+    opcode = instr & kOpcodeMask;
+    DCHECK((opcode == ADDIS) && GetRA(instr).is(kConstantPoolRegister));
+  }
+#endif
+  if (access) {
+    *access = (overflowed ? ConstantPoolEntry::OVERFLOWED
+                          : ConstantPoolEntry::REGULAR);
+  }
+  return true;
+}
+
+
+int Assembler::GetConstantPoolOffset(Address pc,
+                                     ConstantPoolEntry::Access access,
+                                     ConstantPoolEntry::Type type) {
+  bool overflowed = (access == ConstantPoolEntry::OVERFLOWED);
+#ifdef DEBUG
+  ConstantPoolEntry::Access access_check;
+  DCHECK(IsConstantPoolLoadStart(pc, &access_check));
+  DCHECK(access_check == access);
+#endif
+  int offset;
+  if (overflowed) {
+    offset = (instr_at(pc) & kImm16Mask) << 16;
+    offset += SIGN_EXT_IMM16(instr_at(pc + kInstrSize) & kImm16Mask);
+    DCHECK(!is_int16(offset));
+  } else {
+    offset = SIGN_EXT_IMM16((instr_at(pc) & kImm16Mask));
+  }
+  return offset;
+}
+
+
+void Assembler::PatchConstantPoolAccessInstruction(
+    int pc_offset, int offset, ConstantPoolEntry::Access access,
+    ConstantPoolEntry::Type type) {
+  Address pc = buffer_ + pc_offset;
+  bool overflowed = (access == ConstantPoolEntry::OVERFLOWED);
+#ifdef DEBUG
+  ConstantPoolEntry::Access access_check;
+  DCHECK(IsConstantPoolLoadStart(pc, &access_check));
+  DCHECK(access_check == access);
+  DCHECK(overflowed != is_int16(offset));
+#endif
+  if (overflowed) {
+    int hi_word = static_cast<int>(offset >> 16);
+    int lo_word = static_cast<int>(offset & 0xffff);
+    if (lo_word & 0x8000) hi_word++;
+
+    Instr instr1 = instr_at(pc);
+    Instr instr2 = instr_at(pc + kInstrSize);
+    instr1 &= ~kImm16Mask;
+    instr1 |= (hi_word & kImm16Mask);
+    instr2 &= ~kImm16Mask;
+    instr2 |= (lo_word & kImm16Mask);
+    instr_at_put(pc, instr1);
+    instr_at_put(pc + kInstrSize, instr2);
+  } else {
+    Instr instr = instr_at(pc);
+    instr &= ~kImm16Mask;
+    instr |= (offset & kImm16Mask);
+    instr_at_put(pc, instr);
+  }
+}
+
+
+Address Assembler::target_constant_pool_address_at(
+    Address pc, Address constant_pool, ConstantPoolEntry::Access access,
+    ConstantPoolEntry::Type type) {
+  Address addr = constant_pool;
+  DCHECK(addr);
+  addr += GetConstantPoolOffset(pc, access, type);
+  return addr;
+}
+
+
 // This sets the branch destination (which gets loaded at the call address).
 // This is for calls and branches within generated code.  The serializer
 // has already deserialized the mov instructions etc.
 // There is a FIXED_SEQUENCE assumption here
 void Assembler::deserialization_set_special_target_at(
     Address instruction_payload, Code* code, Address target) {
   set_target_address_at(instruction_payload, code, target);
 }
 
 
 void Assembler::deserialization_set_target_internal_reference_at(
     Address pc, Address target, RelocInfo::Mode mode) {
   if (RelocInfo::IsInternalReferenceEncoded(mode)) {
     Code* code = NULL;
     set_target_address_at(pc, code, target, SKIP_ICACHE_FLUSH);
   } else {
     Memory::Address_at(pc) = target;
   }
 }
 
 
 // This code assumes the FIXED_SEQUENCE of lis/ori
-void Assembler::set_target_address_at(Address pc,
-                                      ConstantPoolArray* constant_pool,
+void Assembler::set_target_address_at(Address pc, Address constant_pool,
                                       Address target,
                                       ICacheFlushMode icache_flush_mode) {
+  if (FLAG_enable_embedded_constant_pool && constant_pool) {
+    ConstantPoolEntry::Access access;
+    if (IsConstantPoolLoadStart(pc, &access)) {
+      Memory::Address_at(target_constant_pool_address_at(
+          pc, constant_pool, access, ConstantPoolEntry::INTPTR)) = target;
+      return;
+    }
+  }
+
   Instr instr1 = instr_at(pc);
   Instr instr2 = instr_at(pc + kInstrSize);
   // Interpret 2 instructions generated by lis/ori
   if (IsLis(instr1) && IsOri(instr2)) {
 #if V8_TARGET_ARCH_PPC64
     Instr instr4 = instr_at(pc + (3 * kInstrSize));
     Instr instr5 = instr_at(pc + (4 * kInstrSize));
     // Needs to be fixed up when mov changes to handle 64-bit values.
     uint32_t* p = reinterpret_cast<uint32_t*>(pc);
     uintptr_t itarget = reinterpret_cast<uintptr_t>(target);
@@ skipping 38 matching lines @@
     }
 #endif
     return;
   }
   UNREACHABLE();
 }
 }
 }  // namespace v8::internal
 
 #endif  // V8_PPC_ASSEMBLER_PPC_INL_H_