Smali
Op & FormatMnemonic / SyntaxArgumentsDescription
00 10xnop Waste cycles.

Note: Data-bearing pseudo-instructions are tagged with this opcode, in which case the high-order byte of the opcode unit indicates the nature of the data. See "packed-switch-payload Format", "sparse-switch-payload Format", and "fill-array-data-payload Format" below.

01 12xmove vA, vBA: destination register (4 bits)
B: source register (4 bits)		Move the contents of one non-object register to another.
02 22xmove/from16 vAA, vBBBBA: destination register (8 bits)
B: source register (16 bits)		Move the contents of one non-object register to another.
03 32xmove/16 vAAAA, vBBBBA: destination register (16 bits)
B: source register (16 bits)		Move the contents of one non-object register to another.
04 12xmove-wide vA, vBA: destination register pair (4 bits)
B: source register pair (4 bits)		Move the contents of one register-pair to another.

Note: It is legal to move from vN to either vN-1 or vN+1, so implementations must arrange for both halves of a register pair to be read before anything is written.

05 22xmove-wide/from16 vAA, vBBBBA: destination register pair (8 bits)
B: source register pair (16 bits)		Move the contents of one register-pair to another.

Note: Implementation considerations are the same as move-wide, above.

06 32xmove-wide/16 vAAAA, vBBBBA: destination register pair (16 bits)
B: source register pair (16 bits)		Move the contents of one register-pair to another.

Note: Implementation considerations are the same as move-wide, above.

07 12xmove-object vA, vBA: destination register (4 bits)
B: source register (4 bits)		Move the contents of one object-bearing register to another.
08 22xmove-object/from16 vAA, vBBBBA: destination register (8 bits)
B: source register (16 bits)		Move the contents of one object-bearing register to another.
09 32xmove-object/16 vAAAA, vBBBBA: destination register (16 bits)
B: source register (16 bits)		Move the contents of one object-bearing register to another.
0a 11xmove-result vAAA: destination register (8 bits)Move the single-word non-object result of the most recent invoke-kind into the indicated register. This must be done as the instruction immediately after an invoke-kind whose (single-word, non-object) result is not to be ignored; anywhere else is invalid.
0b 11xmove-result-wide vAAA: destination register pair (8 bits)Move the double-word result of the most recent invoke-kind into the indicated register pair. This must be done as the instruction immediately after an invoke-kind whose (double-word) result is not to be ignored; anywhere else is invalid.
0c 11xmove-result-object vAAA: destination register (8 bits)Move the object result of the most recent invoke-kind into the indicated register. This must be done as the instruction immediately after an invoke-kind or filled-new-array whose (object) result is not to be ignored; anywhere else is invalid.
0d 11xmove-exception vAAA: destination register (8 bits)Save a just-caught exception into the given register. This must be the first instruction of any exception handler whose caught exception is not to be ignored, and this instruction must only ever occur as the first instruction of an exception handler; anywhere else is invalid.
0e 10xreturn-void Return from a void method.
0f 11xreturn vAAA: return value register (8 bits)Return from a single-width (32-bit) non-object value-returning method.
10 11xreturn-wide vAAA: return value register-pair (8 bits)Return from a double-width (64-bit) value-returning method.
11 11xreturn-object vAAA: return value register (8 bits)Return from an object-returning method.
12 11nconst/4 vA, #+BA: destination register (4 bits)
B: signed int (4 bits)		Move the given literal value (sign-extended to 32 bits) into the specified register.
13 21sconst/16 vAA, #+BBBBA: destination register (8 bits)
B: signed int (16 bits)		Move the given literal value (sign-extended to 32 bits) into the specified register.
14 31iconst vAA, #+BBBBBBBBA: destination register (8 bits)
B: arbitrary 32-bit constant		Move the given literal value into the specified register.
15 21hconst/high16 vAA, #+BBBB0000A: destination register (8 bits)
B: signed int (16 bits)		Move the given literal value (right-zero-extended to 32 bits) into the specified register.
16 21sconst-wide/16 vAA, #+BBBBA: destination register (8 bits)
B: signed int (16 bits)		Move the given literal value (sign-extended to 64 bits) into the specified register-pair.
17 31iconst-wide/32 vAA, #+BBBBBBBBA: destination register (8 bits)
B: signed int (32 bits)		Move the given literal value (sign-extended to 64 bits) into the specified register-pair.
18 51lconst-wide vAA, #+BBBBBBBBBBBBBBBBA: destination register (8 bits)
B: arbitrary double-width (64-bit) constant		Move the given literal value into the specified register-pair.
19 21hconst-wide/high16 vAA, #+BBBB000000000000A: destination register (8 bits)
B: signed int (16 bits)		Move the given literal value (right-zero-extended to 64 bits) into the specified register-pair.
1a 21cconst-string vAA, string@BBBBA: destination register (8 bits)
B: string index		Move a reference to the string specified by the given index into the specified register.
1b 31cconst-string/jumbo vAA, string@BBBBBBBBA: destination register (8 bits)
B: string index		Move a reference to the string specified by the given index into the specified register.
1c 21cconst-class vAA, type@BBBBA: destination register (8 bits)
B: type index		Move a reference to the class specified by the given index into the specified register. In the case where the indicated type is primitive, this will store a reference to the primitive type's degenerate class.
1d 11xmonitor-enter vAAA: reference-bearing register (8 bits)Acquire the monitor for the indicated object.
1e 11xmonitor-exit vAAA: reference-bearing register (8 bits)Release the monitor for the indicated object.

Note: If this instruction needs to throw an exception, it must do so as if the pc has already advanced past the instruction. It may be useful to think of this as the instruction successfully executing (in a sense), and the exception getting thrown after the instruction but before the next one gets a chance to run. This definition makes it possible for a method to use a monitor cleanup catch-all (e.g., finally) block as the monitor cleanup for that block itself, as a way to handle the arbitrary exceptions that might get thrown due to the historical implementation of Thread.stop(), while still managing to have proper monitor hygiene.

1f 21ccheck-cast vAA, type@BBBBA: reference-bearing register (8 bits)
B: type index (16 bits)		Throw a ClassCastException if the reference in the given register cannot be cast to the indicated type.

Note: Since A must always be a reference (and not a primitive value), this will necessarily fail at runtime (that is, it will throw an exception) if B refers to a primitive type.

20 22cinstance-of vA, vB, type@CCCCA: destination register (4 bits)
B: reference-bearing register (4 bits)
C: type index (16 bits)		Store in the given destination register 1 if the indicated reference is an instance of the given type, or 0 if not.

Note: Since B must always be a reference (and not a primitive value), this will always result in 0 being stored if C refers to a primitive type.

21 12xarray-length vA, vBA: destination register (4 bits)
B: array reference-bearing register (4 bits)		Store in the given destination register the length of the indicated array, in entries
22 21cnew-instance vAA, type@BBBBA: destination register (8 bits)
B: type index		Construct a new instance of the indicated type, storing a reference to it in the destination. The type must refer to a non-array class.
23 22cnew-array vA, vB, type@CCCCA: destination register (4 bits)
B: size register
C: type index		Construct a new array of the indicated type and size. The type must be an array type.
24 35cfilled-new-array {vC, vD, vE, vF, vG}, type@BBBBA: array size and argument word count (4 bits)
B: type index (16 bits)
C..G: argument registers (4 bits each)		Construct an array of the given type and size, filling it with the supplied contents. The type must be an array type. The array's contents must be single-word (that is, no arrays of long or double, but reference types are acceptable). The constructed instance is stored as a "result" in the same way that the method invocation instructions store their results, so the constructed instance must be moved to a register with an immediately subsequent move-result-object instruction (if it is to be used).
25 3rcfilled-new-array/range {vCCCC .. vNNNN}, type@BBBBA: array size and argument word count (8 bits)
B: type index (16 bits)
C: first argument register (16 bits)
N = A + C - 1		Construct an array of the given type and size, filling it with the supplied contents. Clarifications and restrictions are the same as filled-new-array, described above.
26 31tfill-array-data vAA, +BBBBBBBB (with supplemental data as specified below in "fill-array-data-payload Format")A: array reference (8 bits)
B: signed "branch" offset to table data pseudo-instruction (32 bits)		Fill the given array with the indicated data. The reference must be to an array of primitives, and the data table must match it in type and must contain no more elements than will fit in the array. That is, the array may be larger than the table, and if so, only the initial elements of the array are set, leaving the remainder alone.
27 11xthrow vAAA: exception-bearing register (8 bits)
Throw the indicated exception.
28 10tgoto +AAA: signed branch offset (8 bits)Unconditionally jump to the indicated instruction.

Note: The branch offset must not be 0. (A spin loop may be legally constructed either with goto/32 or by including a nop as a target before the branch.)

29 20tgoto/16 +AAAAA: signed branch offset (16 bits)
Unconditionally jump to the indicated instruction.

Note: The branch offset must not be 0. (A spin loop may be legally constructed either with goto/32 or by including a nop as a target before the branch.)

2a 30tgoto/32 +AAAAAAAAA: signed branch offset (32 bits)
Unconditionally jump to the indicated instruction.
2b 31tpacked-switch vAA, +BBBBBBBB (with supplemental data as specified below in "packed-switch-payload Format")A: register to test
B: signed "branch" offset to table data pseudo-instruction (32 bits)		Jump to a new instruction based on the value in the given register, using a table of offsets corresponding to each value in a particular integral range, or fall through to the next instruction if there is no match.
2c 31tsparse-switch vAA, +BBBBBBBB (with supplemental data as specified below in "sparse-switch-payload Format")A: register to test
B: signed "branch" offset to table data pseudo-instruction (32 bits)		Jump to a new instruction based on the value in the given register, using an ordered table of value-offset pairs, or fall through to the next instruction if there is no match.
2d..31 23xcmpkind vAA, vBB, vCC
2d: cmpl-float (lt bias)
2e: cmpg-float (gt bias)
2f: cmpl-double (lt bias)
30: cmpg-double (gt bias)
31: cmp-long		A: destination register (8 bits)
B: first source register or pair
C: second source register or pair		Perform the indicated floating point or long comparison, setting a to 0 if b == c, 1 if b > c, or -1 if b < c. The "bias" listed for the floating point operations indicates how NaN comparisons are treated: "gt bias" instructions return 1 for NaN comparisons, and "lt bias" instructions return -1.

For example, to check to see if floating point x < y it is advisable to use cmpg-float; a result of -1 indicates that the test was true, and the other values indicate it was false either due to a valid comparison or because one of the values was NaN.

32..37 22tif-test vA, vB, +CCCC
32: if-eq
33: if-ne
34: if-lt
35: if-ge
36: if-gt
37: if-le
A: first register to test (4 bits)
B: second register to test (4 bits)
C: signed branch offset (16 bits)		Branch to the given destination if the given two registers' values compare as specified.

Note: The branch offset must not be 0. (A spin loop may be legally constructed either by branching around a backward goto or by including a nop as a target before the branch.)

38..3d 21tif-testz vAA, +BBBB
38: if-eqz
39: if-nez
3a: if-ltz
3b: if-gez
3c: if-gtz
3d: if-lez
A: register to test (8 bits)
B: signed branch offset (16 bits)		Branch to the given destination if the given register's value compares with 0 as specified.

Note: The branch offset must not be 0. (A spin loop may be legally constructed either by branching around a backward goto or by including a nop as a target before the branch.)

3e..43 10x(unused) (unused)
44..51 23xarrayop vAA, vBB, vCC
44: aget
45: aget-wide
46: aget-object
47: aget-boolean
48: aget-byte
49: aget-char
4a: aget-short
4b: aput
4c: aput-wide
4d: aput-object
4e: aput-boolean
4f: aput-byte
50: aput-char
51: aput-short		A: value register or pair; may be source or dest (8 bits)
B: array register (8 bits)
C: index register (8 bits)		Perform the identified array operation at the identified index of the given array, loading or storing into the value register.
52..5f 22ciinstanceop vA, vB, field@CCCC
52: iget
53: iget-wide
54: iget-object
55: iget-boolean
56: iget-byte
57: iget-char
58: iget-short
59: iput
5a: iput-wide
5b: iput-object
5c: iput-boolean
5d: iput-byte
5e: iput-char
5f: iput-short		A: value register or pair; may be source or dest (4 bits)
B: object register (4 bits)
C: instance field reference index (16 bits)		Perform the identified object instance field operation with the identified field, loading or storing into the value register.

Note: These opcodes are reasonable candidates for static linking, altering the field argument to be a more direct offset.

60..6d 21csstaticop vAA, field@BBBB
60: sget
61: sget-wide
62: sget-object
63: sget-boolean
64: sget-byte
65: sget-char
66: sget-short
67: sput
68: sput-wide
69: sput-object
6a: sput-boolean
6b: sput-byte
6c: sput-char
6d: sput-short		A: value register or pair; may be source or dest (8 bits)
B: static field reference index (16 bits)		Perform the identified object static field operation with the identified static field, loading or storing into the value register.

Note: These opcodes are reasonable candidates for static linking, altering the field argument to be a more direct offset.

6e..72 35cinvoke-kind {vC, vD, vE, vF, vG}, meth@BBBB
6e: invoke-virtual
6f: invoke-super
70: invoke-direct
71: invoke-static
72: invoke-interface		A: argument word count (4 bits)
B: method reference index (16 bits)
C..G: argument registers (4 bits each)		Call the indicated method. The result (if any) may be stored with an appropriate move-result* variant as the immediately subsequent instruction.

invoke-virtual is used to invoke a normal virtual method (a method that is not private, static, or final, and is also not a constructor).

When the method_id references a method of a non-interface class, invoke-super is used to invoke the closest superclass's virtual method (as opposed to the one with the same method_id in the calling class). The same method restrictions hold as for invoke-virtual.

In Dex files version 037 or later, if the method_id refers to an interface method, invoke-super is used to invoke the most specific, non-overridden version of that method defined on that interface. The same method restrictions hold as for invoke-virtual. In Dex files prior to version 037, having an interface method_id is illegal and undefined.

invoke-direct is used to invoke a non-static direct method (that is, an instance method that is by its nature non-overridable, namely either a private instance method or a constructor).

invoke-static is used to invoke a static method (which is always considered a direct method).

invoke-interface is used to invoke an interface method, that is, on an object whose concrete class isn't known, using a method_id that refers to an interface.

Note: These opcodes are reasonable candidates for static linking, altering the method argument to be a more direct offset (or pair thereof).

73 10x(unused) (unused)
74..78 3rcinvoke-kind/range {vCCCC .. vNNNN}, meth@BBBB
74: invoke-virtual/range
75: invoke-super/range
76: invoke-direct/range
77: invoke-static/range
78: invoke-interface/range		A: argument word count (8 bits)
B: method reference index (16 bits)
C: first argument register (16 bits)
N = A + C - 1		Call the indicated method. See first invoke-kind description above for details, caveats, and suggestions.
79..7a 10x(unused) (unused)
7b..8f 12xunop vA, vB
7b: neg-int
7c: not-int
7d: neg-long
7e: not-long
7f: neg-float
80: neg-double
81: int-to-long
82: int-to-float
83: int-to-double
84: long-to-int
85: long-to-float
86: long-to-double
87: float-to-int
88: float-to-long
89: float-to-double
8a: double-to-int
8b: double-to-long
8c: double-to-float
8d: int-to-byte
8e: int-to-char
8f: int-to-short		A: destination register or pair (4 bits)
B: source register or pair (4 bits)		Perform the identified unary operation on the source register, storing the result in the destination register.
90..af 23xbinop vAA, vBB, vCC
90: add-int
91: sub-int
92: mul-int
93: div-int
94: rem-int
95: and-int
96: or-int
97: xor-int
98: shl-int
99: shr-int
9a: ushr-int
9b: add-long
9c: sub-long
9d: mul-long
9e: div-long
9f: rem-long
a0: and-long
a1: or-long
a2: xor-long
a3: shl-long
a4: shr-long
a5: ushr-long
a6: add-float
a7: sub-float
a8: mul-float
a9: div-float
aa: rem-float
ab: add-double
ac: sub-double
ad: mul-double
ae: div-double
af: rem-double		A: destination register or pair (8 bits)
B: first source register or pair (8 bits)
C: second source register or pair (8 bits)		Perform the identified binary operation on the two source registers, storing the result in the destination register.

Note: Contrary to other -long mathematical operations (which take register pairs for both their first and their second source), shl-long, shr-long, and ushr-long take a register pair for their first source (the value to be shifted), but a single register for their second source (the shifting distance).

b0..cf 12xbinop/2addr vA, vB
b0: add-int/2addr
b1: sub-int/2addr
b2: mul-int/2addr
b3: div-int/2addr
b4: rem-int/2addr
b5: and-int/2addr
b6: or-int/2addr
b7: xor-int/2addr
b8: shl-int/2addr
b9: shr-int/2addr
ba: ushr-int/2addr
bb: add-long/2addr
bc: sub-long/2addr
bd: mul-long/2addr
be: div-long/2addr
bf: rem-long/2addr
c0: and-long/2addr
c1: or-long/2addr
c2: xor-long/2addr
c3: shl-long/2addr
c4: shr-long/2addr
c5: ushr-long/2addr
c6: add-float/2addr
c7: sub-float/2addr
c8: mul-float/2addr
c9: div-float/2addr
ca: rem-float/2addr
cb: add-double/2addr
cc: sub-double/2addr
cd: mul-double/2addr
ce: div-double/2addr
cf: rem-double/2addr		A: destination and first source register or pair (4 bits)
B: second source register or pair (4 bits)		Perform the identified binary operation on the two source registers, storing the result in the first source register.

Note: Contrary to other -long/2addr mathematical operations (which take register pairs for both their destination/first source and their second source), shl-long/2addr, shr-long/2addr, and ushr-long/2addr take a register pair for their destination/first source (the value to be shifted), but a single register for their second source (the shifting distance).

d0..d7 22sbinop/lit16 vA, vB, #+CCCC
d0: add-int/lit16
d1: rsub-int (reverse subtract)
d2: mul-int/lit16
d3: div-int/lit16
d4: rem-int/lit16
d5: and-int/lit16
d6: or-int/lit16
d7: xor-int/lit16		A: destination register (4 bits)
B: source register (4 bits)
C: signed int constant (16 bits)		Perform the indicated binary op on the indicated register (first argument) and literal value (second argument), storing the result in the destination register.

Note: rsub-int does not have a suffix since this version is the main opcode of its family. Also, see below for details on its semantics.

d8..e2 22bbinop/lit8 vAA, vBB, #+CC
d8: add-int/lit8
d9: rsub-int/lit8
da: mul-int/lit8
db: div-int/lit8
dc: rem-int/lit8
dd: and-int/lit8
de: or-int/lit8
df: xor-int/lit8
e0: shl-int/lit8
e1: shr-int/lit8
e2: ushr-int/lit8		A: destination register (8 bits)
B: source register (8 bits)
C: signed int constant (8 bits)		Perform the indicated binary op on the indicated register (first argument) and literal value (second argument), storing the result in the destination register.

Note: See below for details on the semantics of rsub-int.

e3..f9 10x(unused) (unused)
fa 45ccinvoke-polymorphic {vC, vD, vE, vF, vG}, meth@BBBB, proto@HHHHA: argument word count (4 bits)
B: method reference index (16 bits)
C: receiver (4 bits)
D..G: argument registers (4 bits each)
H: prototype reference index (16 bits)		Invoke the indicated signature polymorphic method. The result (if any) may be stored with an appropriate move-result* variant as the immediately subsequent instruction.

The method reference must be to a signature polymorphic method, such as java.lang.invoke.MethodHandle.invoke or java.lang.invoke.MethodHandle.invokeExact.

The receiver must be an object supporting the signature polymorphic method being invoked.

The prototype reference describes the argument types provided and the expected return type.

The invoke-polymorphic bytecode may raise exceptions when it executes. The exceptions are described in the API documentation for the signature polymorphic method being invoked.

Present in Dex files from version 038 onwards.
fb 4rccinvoke-polymorphic/range {vCCCC .. vNNNN}, meth@BBBB, proto@HHHHA: argument word count (8 bits)
B: method reference index (16 bits)
C: receiver (16 bits)
H: prototype reference index (16 bits)
N = A + C - 1		Invoke the indicated method handle. See the invoke-polymorphic description above for details.

Present in Dex files from version 038 onwards.
fc 35cinvoke-custom {vC, vD, vE, vF, vG}, call_site@BBBBA: argument word count (4 bits)
B: call site reference index (16 bits)
C..G: argument registers (4 bits each)		Resolves and invokes the indicated call site. The result from the invocation (if any) may be stored with an appropriate move-result* variant as the immediately subsequent instruction.

This instruction executes in two phases: call site resolution and call site invocation.

Call site resolution checks whether the indicated call site has an associated java.lang.invoke.CallSite instance. If not, the bootstrap linker method for the indicated call site is invoked using arguments present in the DEX file (see call_site_item). The bootstrap linker method returns a java.lang.invoke.CallSite instance that will then be associated with the indicated call site if no association exists. Another thread may have already made the association first, and if so execution of the instruction continues with the first associated java.lang.invoke.CallSite instance.

Call site invocation is made on the java.lang.invoke.MethodHandle target of the resolved java.lang.invoke.CallSite instance. The target is invoked as if executing invoke-polymorphic (described above) using the method handle and arguments to the invoke-custom instruction as the arguments to an exact method handle invocation.

Exceptions raised by the bootstrap linker method are wrapped in a java.lang.BootstrapMethodError. A BootstrapMethodError is also raised if:
  • the bootstrap linker method fails to return a java.lang.invoke.CallSite instance.
  • the returned java.lang.invoke.CallSite has a null method handle target.
  • the method handle target is not of the requested type.
Present in Dex files from version 038 onwards.
fd 3rcinvoke-custom/range {vCCCC .. vNNNN}, call_site@BBBBA: argument word count (8 bits)
B: call site reference index (16 bits)
C: first argument register (16-bits)
N = A + C - 1		Resolve and invoke a call site. See the invoke-custom description above for details.

Present in Dex files from version 038 onwards.
fe 21cconst-method-handle vAA, method_handle@BBBBA: destination register (8 bits)
B: method handle index (16 bits)		Move a reference to the method handle specified by the given index into the specified register.

Present in Dex files from version 039 onwards.
ff 21cconst-method-type vAA, proto@BBBBA: destination register (8 bits)
B: method prototype reference (16 bits)		Move a reference to the method prototype specified by the given index into the specified register.

Present in Dex files from version 039 onwards.