ART世界探险(17) - 中层中间代码MIR

简介: 我们从Dalvik指令开始讨论中层中间代码MIR

ART世界探险(17) - 中层中间代码MIR

Dalvik字节码的指令格式

指令格式分类

Dalvik指令,根据需要的寄存器数目的不同,长度也有所不同。
如下面的结构所示,有下面的这些情况:

  enum Format {
    k10x,  // op
    k12x,  // op vA, vB
    k11n,  // op vA, #+B
    k11x,  // op vAA
    k10t,  // op +AA
    k20t,  // op +AAAA
    k22x,  // op vAA, vBBBB
    k21t,  // op vAA, +BBBB
    k21s,  // op vAA, #+BBBB
    k21h,  // op vAA, #+BBBB00000[00000000]
    k21c,  // op vAA, thing@BBBB
    k23x,  // op vAA, vBB, vCC
    k22b,  // op vAA, vBB, #+CC
    k22t,  // op vA, vB, +CCCC
    k22s,  // op vA, vB, #+CCCC
    k22c,  // op vA, vB, thing@CCCC
    k32x,  // op vAAAA, vBBBB
    k30t,  // op +AAAAAAAA
    k31t,  // op vAA, +BBBBBBBB
    k31i,  // op vAA, #+BBBBBBBB
    k31c,  // op vAA, thing@BBBBBBBB
    k35c,  // op {vC, vD, vE, vF, vG}, thing@BBBB (B: count, A: vG)
    k3rc,  // op {vCCCC .. v(CCCC+AA-1)}, meth@BBBB
    k51l,  // op vAA, #+BBBBBBBBBBBBBBBB
  };

计算指令格式长度

MIRGraph的ParseInsn方法就是用来计算指令长度的。

/*
 * Parse an instruction, return the length of the instruction
 */
int MIRGraph::ParseInsn(const uint16_t* code_ptr, MIR::DecodedInstruction* decoded_instruction) {
  const Instruction* inst = Instruction::At(code_ptr);
  decoded_instruction->opcode = inst->Opcode();
  decoded_instruction->vA = inst->HasVRegA() ? inst->VRegA() : 0;
  decoded_instruction->vB = inst->HasVRegB() ? inst->VRegB() : 0;
  decoded_instruction->vB_wide = inst->HasWideVRegB() ? inst->WideVRegB() : 0;
  decoded_instruction->vC = inst->HasVRegC() ?  inst->VRegC() : 0;
  if (inst->HasVarArgs()) {
    inst->GetVarArgs(decoded_instruction->arg);
  }
  return inst->SizeInCodeUnits();
}

MIR中使用的Dalvik指令集

我们之前用了8讲的内容专门讲指令。
下面我们将这些指令的中间细节列一下,大家从下面的表中可以查到每一条指令的格式。

const uint64_t MIRGraph::oat_data_flow_attributes_[kMirOpLast] = {
  // 00 NOP
  DF_NOP,

  // 01 MOVE vA, vB
  DF_DA | DF_UB | DF_IS_MOVE,

  // 02 MOVE_FROM16 vAA, vBBBB
  DF_DA | DF_UB | DF_IS_MOVE,

  // 03 MOVE_16 vAAAA, vBBBB
  DF_DA | DF_UB | DF_IS_MOVE,

  // 04 MOVE_WIDE vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_IS_MOVE,

  // 05 MOVE_WIDE_FROM16 vAA, vBBBB
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_IS_MOVE,

  // 06 MOVE_WIDE_16 vAAAA, vBBBB
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_IS_MOVE,

  // 07 MOVE_OBJECT vA, vB
  DF_DA | DF_UB | DF_NULL_TRANSFER_0 | DF_IS_MOVE | DF_REF_A | DF_REF_B,

  // 08 MOVE_OBJECT_FROM16 vAA, vBBBB
  DF_DA | DF_UB | DF_NULL_TRANSFER_0 | DF_IS_MOVE | DF_REF_A | DF_REF_B,

  // 09 MOVE_OBJECT_16 vAAAA, vBBBB
  DF_DA | DF_UB | DF_NULL_TRANSFER_0 | DF_IS_MOVE | DF_REF_A | DF_REF_B,

  // 0A MOVE_RESULT vAA
  DF_DA,

  // 0B MOVE_RESULT_WIDE vAA
  DF_DA | DF_A_WIDE,

  // 0C MOVE_RESULT_OBJECT vAA
  DF_DA | DF_REF_A,

  // 0D MOVE_EXCEPTION vAA
  DF_DA | DF_REF_A | DF_NON_NULL_DST,

  // 0E RETURN_VOID
  DF_NOP,

  // 0F RETURN vAA
  DF_UA,

  // 10 RETURN_WIDE vAA
  DF_UA | DF_A_WIDE,

  // 11 RETURN_OBJECT vAA
  DF_UA | DF_REF_A,

  // 12 CONST_4 vA, #+B
  DF_DA | DF_SETS_CONST,

  // 13 CONST_16 vAA, #+BBBB
  DF_DA | DF_SETS_CONST,

  // 14 CONST vAA, #+BBBBBBBB
  DF_DA | DF_SETS_CONST,

  // 15 CONST_HIGH16 VAA, #+BBBB0000
  DF_DA | DF_SETS_CONST,

  // 16 CONST_WIDE_16 vAA, #+BBBB
  DF_DA | DF_A_WIDE | DF_SETS_CONST,

  // 17 CONST_WIDE_32 vAA, #+BBBBBBBB
  DF_DA | DF_A_WIDE | DF_SETS_CONST,

  // 18 CONST_WIDE vAA, #+BBBBBBBBBBBBBBBB
  DF_DA | DF_A_WIDE | DF_SETS_CONST,

  // 19 CONST_WIDE_HIGH16 vAA, #+BBBB000000000000
  DF_DA | DF_A_WIDE | DF_SETS_CONST,

  // 1A CONST_STRING vAA, string@BBBB
  DF_DA | DF_REF_A | DF_NON_NULL_DST,

  // 1B CONST_STRING_JUMBO vAA, string@BBBBBBBB
  DF_DA | DF_REF_A | DF_NON_NULL_DST,

  // 1C CONST_CLASS vAA, type@BBBB
  DF_DA | DF_REF_A | DF_NON_NULL_DST,

  // 1D MONITOR_ENTER vAA
  DF_UA | DF_NULL_CHK_A | DF_REF_A,

  // 1E MONITOR_EXIT vAA
  DF_UA | DF_NULL_CHK_A | DF_REF_A,

  // 1F CHK_CAST vAA, type@BBBB
  DF_UA | DF_REF_A | DF_CHK_CAST | DF_UMS,

  // 20 INSTANCE_OF vA, vB, type@CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_REF_B | DF_UMS,

  // 21 ARRAY_LENGTH vA, vB
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_CORE_A | DF_REF_B,

  // 22 NEW_INSTANCE vAA, type@BBBB
  DF_DA | DF_NON_NULL_DST | DF_REF_A | DF_UMS,

  // 23 NEW_ARRAY vA, vB, type@CCCC
  DF_DA | DF_UB | DF_NON_NULL_DST | DF_REF_A | DF_CORE_B | DF_UMS,

  // 24 FILLED_NEW_ARRAY {vD, vE, vF, vG, vA}
  DF_FORMAT_35C | DF_NON_NULL_RET | DF_UMS,

  // 25 FILLED_NEW_ARRAY_RANGE {vCCCC .. vNNNN}, type@BBBB
  DF_FORMAT_3RC | DF_NON_NULL_RET | DF_UMS,

  // 26 FILL_ARRAY_DATA vAA, +BBBBBBBB
  DF_UA | DF_REF_A | DF_UMS,

  // 27 THROW vAA
  DF_UA | DF_REF_A | DF_UMS,

  // 28 GOTO
  DF_NOP,

  // 29 GOTO_16
  DF_NOP,

  // 2A GOTO_32
  DF_NOP,

  // 2B PACKED_SWITCH vAA, +BBBBBBBB
  DF_UA | DF_CORE_A,

  // 2C SPARSE_SWITCH vAA, +BBBBBBBB
  DF_UA | DF_CORE_A,

  // 2D CMPL_FLOAT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_FP_B | DF_FP_C | DF_CORE_A,

  // 2E CMPG_FLOAT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_FP_B | DF_FP_C | DF_CORE_A,

  // 2F CMPL_DOUBLE vAA, vBB, vCC
  DF_DA | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_FP_B | DF_FP_C | DF_CORE_A,

  // 30 CMPG_DOUBLE vAA, vBB, vCC
  DF_DA | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_FP_B | DF_FP_C | DF_CORE_A,

  // 31 CMP_LONG vAA, vBB, vCC
  DF_DA | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 32 IF_EQ vA, vB, +CCCC
  DF_UA | DF_UB | DF_SAME_TYPE_AB,

  // 33 IF_NE vA, vB, +CCCC
  DF_UA | DF_UB | DF_SAME_TYPE_AB,

  // 34 IF_LT vA, vB, +CCCC
  DF_UA | DF_UB | DF_SAME_TYPE_AB,

  // 35 IF_GE vA, vB, +CCCC
  DF_UA | DF_UB | DF_SAME_TYPE_AB,

  // 36 IF_GT vA, vB, +CCCC
  DF_UA | DF_UB | DF_SAME_TYPE_AB,

  // 37 IF_LE vA, vB, +CCCC
  DF_UA | DF_UB | DF_SAME_TYPE_AB,

  // 38 IF_EQZ vAA, +BBBB
  DF_UA,

  // 39 IF_NEZ vAA, +BBBB
  DF_UA,

  // 3A IF_LTZ vAA, +BBBB
  DF_UA,

  // 3B IF_GEZ vAA, +BBBB
  DF_UA,

  // 3C IF_GTZ vAA, +BBBB
  DF_UA,

  // 3D IF_LEZ vAA, +BBBB
  DF_UA,

  // 3E UNUSED_3E
  DF_NOP,

  // 3F UNUSED_3F
  DF_NOP,

  // 40 UNUSED_40
  DF_NOP,

  // 41 UNUSED_41
  DF_NOP,

  // 42 UNUSED_42
  DF_NOP,

  // 43 UNUSED_43
  DF_NOP,

  // 44 AGET vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 45 AGET_WIDE vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 46 AGET_OBJECT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_A | DF_REF_B | DF_CORE_C | DF_LVN,

  // 47 AGET_BOOLEAN vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 48 AGET_BYTE vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 49 AGET_CHAR vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 4A AGET_SHORT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 4B APUT vAA, vBB, vCC
  DF_UA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 4C APUT_WIDE vAA, vBB, vCC
  DF_UA | DF_A_WIDE | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 4D APUT_OBJECT vAA, vBB, vCC
  DF_UA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_A | DF_REF_B | DF_CORE_C | DF_LVN,

  // 4E APUT_BOOLEAN vAA, vBB, vCC
  DF_UA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 4F APUT_BYTE vAA, vBB, vCC
  DF_UA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 50 APUT_CHAR vAA, vBB, vCC
  DF_UA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 51 APUT_SHORT vAA, vBB, vCC
  DF_UA | DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 52 IGET vA, vB, field@CCCC
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 53 IGET_WIDE vA, vB, field@CCCC
  DF_DA | DF_A_WIDE | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 54 IGET_OBJECT vA, vB, field@CCCC
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_A | DF_REF_B | DF_IFIELD | DF_LVN,

  // 55 IGET_BOOLEAN vA, vB, field@CCCC
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 56 IGET_BYTE vA, vB, field@CCCC
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 57 IGET_CHAR vA, vB, field@CCCC
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 58 IGET_SHORT vA, vB, field@CCCC
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 59 IPUT vA, vB, field@CCCC
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 5A IPUT_WIDE vA, vB, field@CCCC
  DF_UA | DF_A_WIDE | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 5B IPUT_OBJECT vA, vB, field@CCCC
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_A | DF_REF_B | DF_IFIELD | DF_LVN,

  // 5C IPUT_BOOLEAN vA, vB, field@CCCC
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 5D IPUT_BYTE vA, vB, field@CCCC
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 5E IPUT_CHAR vA, vB, field@CCCC
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 5F IPUT_SHORT vA, vB, field@CCCC
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // 60 SGET vAA, field@BBBB
  DF_DA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 61 SGET_WIDE vAA, field@BBBB
  DF_DA | DF_A_WIDE | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 62 SGET_OBJECT vAA, field@BBBB
  DF_DA | DF_REF_A | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 63 SGET_BOOLEAN vAA, field@BBBB
  DF_DA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 64 SGET_BYTE vAA, field@BBBB
  DF_DA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 65 SGET_CHAR vAA, field@BBBB
  DF_DA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 66 SGET_SHORT vAA, field@BBBB
  DF_DA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 67 SPUT vAA, field@BBBB
  DF_UA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 68 SPUT_WIDE vAA, field@BBBB
  DF_UA | DF_A_WIDE | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 69 SPUT_OBJECT vAA, field@BBBB
  DF_UA | DF_REF_A | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 6A SPUT_BOOLEAN vAA, field@BBBB
  DF_UA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 6B SPUT_BYTE vAA, field@BBBB
  DF_UA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 6C SPUT_CHAR vAA, field@BBBB
  DF_UA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 6D SPUT_SHORT vAA, field@BBBB
  DF_UA | DF_SFIELD | DF_CLINIT | DF_UMS,

  // 6E INVOKE_VIRTUAL {vD, vE, vF, vG, vA}
  DF_FORMAT_35C | DF_NULL_CHK_OUT0 | DF_UMS,

  // 6F INVOKE_SUPER {vD, vE, vF, vG, vA}
  DF_FORMAT_35C | DF_NULL_CHK_OUT0 | DF_UMS,

  // 70 INVOKE_DIRECT {vD, vE, vF, vG, vA}
  DF_FORMAT_35C | DF_NULL_CHK_OUT0 | DF_UMS,

  // 71 INVOKE_STATIC {vD, vE, vF, vG, vA}
  DF_FORMAT_35C | DF_CLINIT | DF_UMS,

  // 72 INVOKE_INTERFACE {vD, vE, vF, vG, vA}
  DF_FORMAT_35C | DF_NULL_CHK_OUT0 | DF_UMS,

  // 73 RETURN_VOID_NO_BARRIER
  DF_NOP,

  // 74 INVOKE_VIRTUAL_RANGE {vCCCC .. vNNNN}
  DF_FORMAT_3RC | DF_NULL_CHK_OUT0 | DF_UMS,

  // 75 INVOKE_SUPER_RANGE {vCCCC .. vNNNN}
  DF_FORMAT_3RC | DF_NULL_CHK_OUT0 | DF_UMS,

  // 76 INVOKE_DIRECT_RANGE {vCCCC .. vNNNN}
  DF_FORMAT_3RC | DF_NULL_CHK_OUT0 | DF_UMS,

  // 77 INVOKE_STATIC_RANGE {vCCCC .. vNNNN}
  DF_FORMAT_3RC | DF_CLINIT | DF_UMS,

  // 78 INVOKE_INTERFACE_RANGE {vCCCC .. vNNNN}
  DF_FORMAT_3RC | DF_NULL_CHK_OUT0 | DF_UMS,

  // 79 UNUSED_79
  DF_NOP,

  // 7A UNUSED_7A
  DF_NOP,

  // 7B NEG_INT vA, vB
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // 7C NOT_INT vA, vB
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // 7D NEG_LONG vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // 7E NOT_LONG vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // 7F NEG_FLOAT vA, vB
  DF_DA | DF_UB | DF_FP_A | DF_FP_B,

  // 80 NEG_DOUBLE vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // 81 INT_TO_LONG vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_CORE_A | DF_CORE_B,

  // 82 INT_TO_FLOAT vA, vB
  DF_DA | DF_UB | DF_FP_A | DF_CORE_B,

  // 83 INT_TO_DOUBLE vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_FP_A | DF_CORE_B,

  // 84 LONG_TO_INT vA, vB
  DF_DA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // 85 LONG_TO_FLOAT vA, vB
  DF_DA | DF_UB | DF_B_WIDE | DF_FP_A | DF_CORE_B,

  // 86 LONG_TO_DOUBLE vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_FP_A | DF_CORE_B,

  // 87 FLOAT_TO_INT vA, vB
  DF_DA | DF_UB | DF_FP_B | DF_CORE_A,

  // 88 FLOAT_TO_LONG vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_FP_B | DF_CORE_A,

  // 89 FLOAT_TO_DOUBLE vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_FP_A | DF_FP_B,

  // 8A DOUBLE_TO_INT vA, vB
  DF_DA | DF_UB | DF_B_WIDE | DF_FP_B | DF_CORE_A,

  // 8B DOUBLE_TO_LONG vA, vB
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_FP_B | DF_CORE_A,

  // 8C DOUBLE_TO_FLOAT vA, vB
  DF_DA | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // 8D INT_TO_BYTE vA, vB
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // 8E INT_TO_CHAR vA, vB
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // 8F INT_TO_SHORT vA, vB
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // 90 ADD_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 91 SUB_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 92 MUL_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 93 DIV_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 94 REM_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 95 AND_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 96 OR_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 97 XOR_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 98 SHL_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 99 SHR_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 9A USHR_INT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 9B ADD_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 9C SUB_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 9D MUL_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 9E DIV_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // 9F REM_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // A0 AND_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // A1 OR_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // A2 XOR_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // A3 SHL_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // A4 SHR_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // A5 USHR_LONG vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_CORE_A | DF_CORE_B | DF_CORE_C,

  // A6 ADD_FLOAT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_FP_A | DF_FP_B | DF_FP_C,

  // A7 SUB_FLOAT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_FP_A | DF_FP_B | DF_FP_C,

  // A8 MUL_FLOAT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_FP_A | DF_FP_B | DF_FP_C,

  // A9 DIV_FLOAT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_FP_A | DF_FP_B | DF_FP_C,

  // AA REM_FLOAT vAA, vBB, vCC
  DF_DA | DF_UB | DF_UC | DF_FP_A | DF_FP_B | DF_FP_C,

  // AB ADD_DOUBLE vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_FP_A | DF_FP_B | DF_FP_C,

  // AC SUB_DOUBLE vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_FP_A | DF_FP_B | DF_FP_C,

  // AD MUL_DOUBLE vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_FP_A | DF_FP_B | DF_FP_C,

  // AE DIV_DOUBLE vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_FP_A | DF_FP_B | DF_FP_C,

  // AF REM_DOUBLE vAA, vBB, vCC
  DF_DA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_UC | DF_C_WIDE | DF_FP_A | DF_FP_B | DF_FP_C,

  // B0 ADD_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B1 SUB_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B2 MUL_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B3 DIV_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B4 REM_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B5 AND_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B6 OR_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B7 XOR_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B8 SHL_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // B9 SHR_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // BA USHR_INT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // BB ADD_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // BC SUB_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // BD MUL_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // BE DIV_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // BF REM_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // C0 AND_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // C1 OR_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // C2 XOR_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // C3 SHL_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // C4 SHR_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // C5 USHR_LONG_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_CORE_A | DF_CORE_B,

  // C6 ADD_FLOAT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_FP_A | DF_FP_B,

  // C7 SUB_FLOAT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_FP_A | DF_FP_B,

  // C8 MUL_FLOAT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_FP_A | DF_FP_B,

  // C9 DIV_FLOAT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_FP_A | DF_FP_B,

  // CA REM_FLOAT_2ADDR vA, vB
  DF_DA | DF_UA | DF_UB | DF_FP_A | DF_FP_B,

  // CB ADD_DOUBLE_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // CC SUB_DOUBLE_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // CD MUL_DOUBLE_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // CE DIV_DOUBLE_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // CF REM_DOUBLE_2ADDR vA, vB
  DF_DA | DF_A_WIDE | DF_UA | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // D0 ADD_INT_LIT16 vA, vB, #+CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D1 RSUB_INT vA, vB, #+CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D2 MUL_INT_LIT16 vA, vB, #+CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D3 DIV_INT_LIT16 vA, vB, #+CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D4 REM_INT_LIT16 vA, vB, #+CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D5 AND_INT_LIT16 vA, vB, #+CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D6 OR_INT_LIT16 vA, vB, #+CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D7 XOR_INT_LIT16 vA, vB, #+CCCC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D8 ADD_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // D9 RSUB_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // DA MUL_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // DB DIV_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // DC REM_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // DD AND_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // DE OR_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // DF XOR_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // E0 SHL_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // E1 SHR_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // E2 USHR_INT_LIT8 vAA, vBB, #+CC
  DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,

  // E3 IGET_QUICK
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // E4 IGET_WIDE_QUICK
  DF_DA | DF_A_WIDE | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // E5 IGET_OBJECT_QUICK
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_A | DF_REF_B | DF_IFIELD | DF_LVN,

  // E6 IPUT_QUICK
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // E7 IPUT_WIDE_QUICK
  DF_UA | DF_A_WIDE | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // E8 IPUT_OBJECT_QUICK
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_A | DF_REF_B | DF_IFIELD | DF_LVN,

  // E9 INVOKE_VIRTUAL_QUICK
  DF_FORMAT_35C | DF_NULL_CHK_OUT0 | DF_UMS,

  // EA INVOKE_VIRTUAL_RANGE_QUICK
  DF_FORMAT_3RC | DF_NULL_CHK_OUT0 | DF_UMS,

  // EB IPUT_BOOLEAN_QUICK vA, vB, index
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // EC IPUT_BYTE_QUICK vA, vB, index
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // ED IPUT_CHAR_QUICK vA, vB, index
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // EE IPUT_SHORT_QUICK vA, vB, index
  DF_UA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // EF IGET_BOOLEAN_QUICK vA, vB, index
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // F0 IGET_BYTE_QUICK vA, vB, index
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // F1 IGET_CHAR_QUICK vA, vB, index
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // F2 IGET_SHORT_QUICK vA, vB, index
  DF_DA | DF_UB | DF_NULL_CHK_B | DF_REF_B | DF_IFIELD | DF_LVN,

  // F3 UNUSED_F3
  DF_NOP,

  // F4 UNUSED_F4
  DF_NOP,

  // F5 UNUSED_F5
  DF_NOP,

  // F6 UNUSED_F6
  DF_NOP,

  // F7 UNUSED_F7
  DF_NOP,

  // F8 UNUSED_F8
  DF_NOP,

  // F9 UNUSED_F9
  DF_NOP,

  // FA UNUSED_FA
  DF_NOP,

  // FB UNUSED_FB
  DF_NOP,

  // FC UNUSED_FC
  DF_NOP,

  // FD UNUSED_FD
  DF_NOP,

  // FE UNUSED_FE
  DF_NOP,

  // FF UNUSED_FF
  DF_NOP,

  // Beginning of extended MIR opcodes
  // 100 MIR_PHI
  DF_DA | DF_NULL_TRANSFER_N,

  // 101 MIR_COPY
  DF_DA | DF_UB | DF_IS_MOVE,

  // 102 MIR_FUSED_CMPL_FLOAT
  DF_UA | DF_UB | DF_FP_A | DF_FP_B,

  // 103 MIR_FUSED_CMPG_FLOAT
  DF_UA | DF_UB | DF_FP_A | DF_FP_B,

  // 104 MIR_FUSED_CMPL_DOUBLE
  DF_UA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // 105 MIR_FUSED_CMPG_DOUBLE
  DF_UA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_FP_A | DF_FP_B,

  // 106 MIR_FUSED_CMP_LONG
  DF_UA | DF_A_WIDE | DF_UB | DF_B_WIDE | DF_CORE_A | DF_CORE_B,

  // 107 MIR_NOP
  DF_NOP,

  // 108 MIR_NULL_CHECK
  DF_UA | DF_REF_A | DF_NULL_CHK_A | DF_LVN,

  // 109 MIR_RANGE_CHECK
  0,

  // 10A MIR_DIV_ZERO_CHECK
  0,

  // 10B MIR_CHECK
  0,

  // 10D MIR_SELECT
  DF_DA | DF_UB,

  // 10E MirOpConstVector
  0,

  // 10F MirOpMoveVector
  0,

  // 110 MirOpPackedMultiply
  0,

  // 111 MirOpPackedAddition
  0,

  // 112 MirOpPackedSubtract
  0,

  // 113 MirOpPackedShiftLeft
  0,

  // 114 MirOpPackedSignedShiftRight
  0,

  // 115 MirOpPackedUnsignedShiftRight
  0,

  // 116 MirOpPackedAnd
  0,

  // 117 MirOpPackedOr
  0,

  // 118 MirOpPackedXor
  0,

  // 119 MirOpPackedAddReduce
  DF_FORMAT_EXTENDED,

  // 11A MirOpPackedReduce
  DF_FORMAT_EXTENDED,

  // 11B MirOpPackedSet
  DF_FORMAT_EXTENDED,

  // 11C MirOpReserveVectorRegisters
  0,

  // 11D MirOpReturnVectorRegisters
  0,

  // 11E MirOpMemBarrier
  0,

  // 11F MirOpPackedArrayGet
  DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 120 MirOpPackedArrayPut
  DF_UB | DF_UC | DF_NULL_CHK_B | DF_RANGE_CHK_C | DF_REF_B | DF_CORE_C | DF_LVN,

  // 121 MirOpMaddInt
  DF_FORMAT_EXTENDED,

  // 122 MirOpMsubInt
  DF_FORMAT_EXTENDED,

  // 123 MirOpMaddLong
  DF_FORMAT_EXTENDED,

  // 124 MirOpMsubLong
  DF_FORMAT_EXTENDED,
};

MIR

生成一条MIR

// Allocate a new MIR.
MIR* MIRGraph::NewMIR() {
  MIR* mir = new (arena_) MIR();
  return mir;
}

代码块 - BasicBlock

我们都知道,Java中的代码是由一个个代码块所组成的。

代码块的类型 - BBType

enum BBType {
  kNullBlock,
  kEntryBlock,
  kDalvikByteCode,
  kExitBlock,
  kExceptionHandling,
  kDead,
};

代码块列表类型

enum BlockListType {
  kNotUsed = 0,
  kCatch,
  kPackedSwitch,
  kSparseSwitch,
};

基本块的数据流

// Dataflow attributes of a basic block.
struct BasicBlockDataFlow {
  ArenaBitVector* use_v;
  ArenaBitVector* def_v;
  ArenaBitVector* live_in_v;
  int32_t* vreg_to_ssa_map_exit;
};

基本代码块的创建 - CreateNewBB方法

  1. 首先根据block_list_中已有的基本代码块的数目生成新的BasicBlockId。
  2. 然后调用NewMemBB去真正分配空间。
  3. 生成之后,再压到block_list_向量中。
BasicBlock* MIRGraph::CreateNewBB(BBType block_type) {
  BasicBlockId id = static_cast<BasicBlockId>(block_list_.size());
  BasicBlock* res = NewMemBB(block_type, id);
  block_list_.push_back(res);
  return res;
}

分配一个基本代码块

主要是预留出相应的空间来。
另外还要到block_id_map_中备个案。

// Allocate a new basic block.
BasicBlock* MIRGraph::NewMemBB(BBType block_type, int block_id) {
  BasicBlock* bb = new (arena_) BasicBlock(block_id, block_type, arena_);

  // TUNING: better estimate of the exit block predecessors?
  bb->predecessors.reserve((block_type == kExitBlock) ? 2048 : 2);
  block_id_map_.Put(block_id, block_id);
  return bb;
}

代码项

Dex文件中的代码项,用CodeItem结构体来表示:

  struct CodeItem {
    uint16_t registers_size_;
    uint16_t ins_size_;
    uint16_t outs_size_;
    uint16_t tries_size_;
    uint32_t debug_info_off_;  // file offset to debug info stream
    uint32_t insns_size_in_code_units_;  // size of the insns array, in 2 byte code units
    uint16_t insns_[1];

   private:
    DISALLOW_COPY_AND_ASSIGN(CodeItem);
  };

调用类型

调用方法的类型有以下几种:

  • kStatic:调用静态方法
  • kDirect:调用普通方法
  • kVirtual:调用虚方法
  • kSuper:调用父类方法
  • kInterface:调用实现的接口中的方法
enum InvokeType {
  kStatic,     // <<static>>
  kDirect,     // <<direct>>
  kVirtual,    // <<virtual>>
  kSuper,      // <<super>>
  kInterface,  // <<interface>>
  kMaxInvokeType = kInterface
};

最后,我们上一张MIRGraph的大图. 后面几节我们主要都是跟它打交道了

MIRGraph

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