DBC: CheckClassInstr

runtime/vm/constants_dbc.h

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_CONSTANTS_DBC_H_
 #define VM_CONSTANTS_DBC_H_
 
 #include "platform/globals.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 65 matching lines @@
 //   | opcode |             T            |   T: signed 24-bit operand
 //   +--------+--------+--------+--------+
 //
 //
 // INSTRUCTIONS
 //
 //  - Trap
 //
 //    Unreachable instruction.
 //
-//  - Nop
+//  - Nop D
 //
-//    This instuction does nothing.
+//    This instuction does nothing. It may refer to an object in the constant
+//    pool that may be decoded by other instructions.
 //
 //  - Compile
 //
 //    Compile current function and start executing newly produced code
 //    (used to implement LazyCompileStub);
 //
 //  - Intrinsic id
 //
 //    Execute intrinsic with the given id. If intrinsic returns true then
 //    return from the current function to the caller passing value produced
@@ skipping 106 matching lines @@
 //
 //    Skips the next instruction unless the given condition holds. 'Num'
 //    variants perform number check while non-Num variants just compare
 //    RawObject pointers.
 //
 //    Used to implement conditional jump:
 //
 //        IfNeStrictTOS
 //        Jump T         ;; jump if not equal
 //
+//  - If<Cond>Null rA
+//
+//    Cond is Eq or Ne. Skips the next instruction unless the given condition
+//    holds.
+//
 //  - CreateArrayTOS
 //
 //    Allocate array of length SP[0] with type arguments SP[-1].
 //
 //  - Allocate D
 //
 //    Allocate object of class PP[D] with no type arguments.
 //
 //  - AllocateT
 //
@@ skipping 126 matching lines @@
 //
 //  - CheckSmi rA
 //
 //    If FP[rA] is a Smi, then skip the next instruction.
 //
 //  - CheckClassId rA, D
 //
 //    If the object at FP[rA]'s class id matches hthe class id in PP[D], then
 //    skip the following instruction.
 //
+//  - CheckDenseSwitch rA, D
+//
+//    Skips the next 3 instructions if the object at FP[rA] is a valid class for
+//    a dense switch with low cid encoded in the following Nop instruction, and
+//    the cid mask encoded in the Nop instruction after that, or if D == 1 and
+//    FP[rA] is a Smi. Skips 2 instructions otherwise.
+//
+//  - CheckCid rA, D

[Vyacheslav Egorov (Google), 2016/06/29 17:11:06]

32bit build allocates only 16bits for a CID. I think it's fair to assume even in
64-bit build that CID is 16bit (because application with more than 2^16 classes
will not run on 32-bit build anyway).

Also I suggest not having can_be_smi flag for a single cid comparison. Value can
be smi iff cid we are checking against is kSmiCid.

[zra, 2016/06/29 22:19:17]

Done.

+//
+//    Skips the next two instructions if the object at FP[rA] is a Smi and
+//    D == 1, or if FP[rA] has cid equal to the cid encoded by the following
+//    Nop instruction. Otherwise skips 1 instruction.
+//
+//  - CheckCids rA, D
+//
+//    Skips the next two instructions if the object at FP[rA] is a Smi and
+//    D == 1, or if FP[rA]'s cid is found in the array of cids encoded by the
+//    following Nop instruction. Otherwise skips 1 instruction.
+//
 //  - CheckStack
 //
 //    Compare SP against isolate stack limit and call StackOverflow handler if
 //    necessary.
 //
 //  - DebugStep, DebugBreak A
 //
 //    Debugger support. DebugBreak is bytecode that can be patched into the
 //    instruction stream to trigger in place breakpoint.
 //
@@ skipping 42 matching lines @@
 //     reg register (unsigned FP relative local)
 //     xeg x-register (signed FP relative local)
 //     tgt jump target relative to the PC of the current instruction
 //
 // TODO(vegorov) jump targets should be encoded relative to PC of the next
 //               instruction because PC is incremeted immediately after fetch
 //               and before decoding.
 //
 #define BYTECODES_LIST(V)                              \
   V(Trap,                            0, ___, ___, ___) \
-  V(Nop,                             0, ___, ___, ___) \
+  V(Nop,                             D, lit, ___, ___) \
   V(Compile,                         0, ___, ___, ___) \
   V(HotCheck,                      A_D, num, num, ___) \
   V(Intrinsic,                       A, num, ___, ___) \
   V(Drop1,                           0, ___, ___, ___) \
   V(DropR,                           A, num, ___, ___) \
   V(Drop,                            A, num, ___, ___) \
   V(Jump,                            T, tgt, ___, ___) \
   V(Return,                          A, reg, ___, ___) \
   V(ReturnTOS,                       0, ___, ___, ___) \
   V(Move,                          A_X, reg, xeg, ___) \
@@ skipping 36 matching lines @@
   V(PushStatic,                      D, lit, ___, ___) \
   V(InitStaticTOS,                   0, ___, ___, ___) \
   V(IfNeStrictTOS,                   0, ___, ___, ___) \
   V(IfEqStrictTOS,                   0, ___, ___, ___) \
   V(IfNeStrictNumTOS,                0, ___, ___, ___) \
   V(IfEqStrictNumTOS,                0, ___, ___, ___) \
   V(IfNeStrict,                    A_D, reg, reg, ___) \
   V(IfEqStrict,                    A_D, reg, reg, ___) \
   V(IfNeStrictNum,                 A_D, reg, reg, ___) \
   V(IfEqStrictNum,                 A_D, reg, reg, ___) \
+  V(IfEqNull,                        A, reg, ___, ___) \
+  V(IfNeNull,                        A, reg, ___, ___) \
   V(CreateArrayTOS,                  0, ___, ___, ___) \
   V(Allocate,                        D, lit, ___, ___) \
   V(AllocateT,                       0, ___, ___, ___) \
   V(StoreIndexedTOS,                 0, ___, ___, ___) \
   V(StoreIndexed,                A_B_C, reg, reg, reg) \
   V(StoreField,                  A_B_C, reg, num, reg) \
   V(StoreFieldTOS,                   D, num, ___, ___) \
   V(LoadField,                   A_B_C, reg, reg, num) \
   V(LoadFieldTOS,                    D, num, ___, ___) \
   V(BooleanNegateTOS,                0, ___, ___, ___) \
   V(BooleanNegate,                 A_D, reg, reg, ___) \
   V(Throw,                           A, num, ___, ___) \
   V(Entry,                       A_B_C, num, num, num) \
   V(EntryOptional,               A_B_C, num, num, num) \
   V(EntryOptimized,                A_D, num, num, ___) \
   V(Frame,                           D, num, ___, ___) \
   V(SetFrame,                        A, num, ___, num) \
   V(AllocateContext,                 D, num, ___, ___) \
   V(CloneContext,                    0, ___, ___, ___) \
   V(MoveSpecial,                   A_D, reg, num, ___) \
   V(InstantiateType,                 D, lit, ___, ___) \
   V(InstantiateTypeArgumentsTOS,   A_D, num, lit, ___) \
   V(AssertAssignable,                D, num, lit, ___) \
   V(AssertBoolean,                   A, num, ___, ___) \
   V(CheckSmi,                        A, reg, ___, ___) \
   V(CheckClassId,                  A_D, reg, lit, ___) \
+  V(CheckDenseSwitch,              A_D, reg, num, ___) \
+  V(CheckCid,                      A_D, reg, num, ___) \
+  V(CheckCids,                     A_D, reg, num, ___) \
   V(CheckStack,                      0, ___, ___, ___) \
   V(DebugStep,                       0, ___, ___, ___) \
   V(DebugBreak,                      A, num, ___, ___) \
   V(Deopt,                         A_D, num, num, ___) \
 
 typedef uint32_t Instr;
 
 class Bytecode {
  public:
   enum Opcode {
@@ skipping 102 matching lines @@
   kNumberOfDummyFpuRegisters,
 };
 const FpuRegister FpuTMP = kFakeFpuRegister;
 const intptr_t kNumberOfFpuRegisters = 1;
 
 enum Condition { EQ, NE };
 
 }  // namespace dart
 
 #endif  // VM_CONSTANTS_DBC_H_