Line data    Source code

       1             : // Copyright 2012 the V8 project authors. All rights reserved.
       2             : // Use of this source code is governed by a BSD-style license that can be
       3             : // found in the LICENSE file.
       4             : 
       5             : #if V8_TARGET_ARCH_X64
       6             : 
       7             : #include "src/codegen.h"
       8             : #include "src/ic/ic.h"
       9             : #include "src/ic/stub-cache.h"
      10             : #include "src/objects-inl.h"
      11             : 
      12             : namespace v8 {
      13             : namespace internal {
      14             : 
      15             : 
      16      465231 : Condition CompareIC::ComputeCondition(Token::Value op) {
      17      465231 :   switch (op) {
      18             :     case Token::EQ_STRICT:
      19             :     case Token::EQ:
      20             :       return equal;
      21             :     case Token::LT:
      22       85130 :       return less;
      23             :     case Token::GT:
      24       43418 :       return greater;
      25             :     case Token::LTE:
      26        8210 :       return less_equal;
      27             :     case Token::GTE:
      28       12442 :       return greater_equal;
      29             :     default:
      30           0 :       UNREACHABLE();
      31             :       return no_condition;
      32             :   }
      33             : }
      34             : 
      35             : 
      36      272912 : bool CompareIC::HasInlinedSmiCode(Address address) {
      37             :   // The address of the instruction following the call.
      38             :   Address test_instruction_address =
      39             :       address + Assembler::kCallTargetAddressOffset;
      40             : 
      41             :   // If the instruction following the call is not a test al, nothing
      42             :   // was inlined.
      43      272912 :   return *test_instruction_address == Assembler::kTestAlByte;
      44             : }
      45             : 
      46             : 
      47      633394 : void PatchInlinedSmiCode(Isolate* isolate, Address address,
      48             :                          InlinedSmiCheck check) {
      49             :   // The address of the instruction following the call.
      50             :   Address test_instruction_address =
      51      633394 :       address + Assembler::kCallTargetAddressOffset;
      52             : 
      53             :   // If the instruction following the call is not a test al, nothing
      54             :   // was inlined.
      55      633394 :   if (*test_instruction_address != Assembler::kTestAlByte) {
      56             :     DCHECK(*test_instruction_address == Assembler::kNopByte);
      57      633394 :     return;
      58             :   }
      59             : 
      60             :   Address delta_address = test_instruction_address + 1;
      61             :   // The delta to the start of the map check instruction and the
      62             :   // condition code uses at the patched jump.
      63      210442 :   uint8_t delta = *reinterpret_cast<uint8_t*>(delta_address);
      64      210442 :   if (FLAG_trace_ic) {
      65           0 :     LOG(isolate, PatchIC(address, test_instruction_address, delta));
      66             :   }
      67             : 
      68             :   // Patch with a short conditional jump. Enabling means switching from a short
      69             :   // jump-if-carry/not-carry to jump-if-zero/not-zero, whereas disabling is the
      70             :   // reverse operation of that.
      71      210442 :   Address jmp_address = test_instruction_address - delta;
      72             :   DCHECK((check == ENABLE_INLINED_SMI_CHECK)
      73             :              ? (*jmp_address == Assembler::kJncShortOpcode ||
      74             :                 *jmp_address == Assembler::kJcShortOpcode)
      75             :              : (*jmp_address == Assembler::kJnzShortOpcode ||
      76             :                 *jmp_address == Assembler::kJzShortOpcode));
      77             :   Condition cc =
      78             :       (check == ENABLE_INLINED_SMI_CHECK)
      79      210440 :           ? (*jmp_address == Assembler::kJncShortOpcode ? not_zero : zero)
      80      420882 :           : (*jmp_address == Assembler::kJnzShortOpcode ? not_carry : carry);
      81      210442 :   *jmp_address = static_cast<byte>(Assembler::kJccShortPrefix | cc);
      82             : }
      83             : }  // namespace internal
      84             : }  // namespace v8
      85             : 
      86             : #endif  // V8_TARGET_ARCH_X64