[转]jvm opcode instruction

A.3 Instructions by Category This section contains a listing of the instructions and what they do, grouped by category. Here is a key to the descriptions: a The top slot of the stack. May be an int, float, or reference. b The second stack slot. May be an int, float, or reference. c The third stack slot. May be an int, float, or reference. d The fourth stack slot. May be an int, float, or reference. ab The long or double on top of the stack, made up of slots a and b. cd The long or double second on the stack, made up of slots c and d. A.3.1 Arithmetic Mnemonic Arguments Description dadd Add double (ab+cd) dcmpg Compare double dcmpl Compare double ddiv Divide double (ab/cd) dmul Multiply double (ab*cd) dneg Negate double (-ab) drem Remainder double (ab%cd) dsub Subtract double (ab-cd) fadd Add float (a+b) fcmpg Compare float fcmpl Compare float fdiv Divide float (a/b) fmul Multiply float (a*b) fneg Negate float (-a) frem Remainder float (a%b) fsub Subtract float (a-b) i2b Convert int to byte i2c Convert int to char i2s Convert int to short iadd Add int (a+b) iand Bitwise and ints (a & b) idiv Divide ints (a/b) imul Multiply ints (a*b) ineg Negate int (-a) ior Bitwise or ints (a b) irem Remainder int (a%b) ishl Shift int left (a << b) ishr Shift int right (a >> c) isub Subtract int (a-b) iushr Unsigned shift int right (a >>> c) ixor Bitwise xor ints (a ^ b) ladd Add long (ab+cd) land Bitwise and longs (ab & cd) lcmp Compare longs ldiv Divide long (ab/cd) lmul Multiply long (ab*cd) lneg Negate long (-ab) lor Bitwise or longs (ab cd) lrem Remainder longs (ab%cd) lshl Shift long left (bc << 9) lshr Shift long right (bc >> 9) lsub Subtract long (ab-cd) lushr Unsigned shift long right (bc >>> 9) lxor Bitwise x or longs (ab ^ cd) A.3.2 Array Mnemonic Arguments Description aaload Push array element a from array b aastore Store a in array element b of array c anewarray class Create array of class, length a arraylength Length of array a athrow Throw exception a baload Push array element a from array b bastore Store a in array element b of array c caload Push array element a from array b castore Store a in array element daload Push array element a from array b dastore Store ab in array element faload Push array element a from array b fastore Store a in array element b of array c iaload Push array element a from array b iastore Store a in array element laload Push array element a from array b lastore Store ab in array element c of array d multianewarray class n Create multidimensional array with first n dimensions initialized to lengths a, b, c. . . newarray type Create array of type, length a saload Push array element a from array b sastore Store a in array element b of array c A.3.3 Constant Mnemonic Arguments Description aconst_null Push null reference bipush n Push int between ?28 and 127 dconst_0 Push 0 (double) dconst_1 Push 1 (double) fconst_0 Push 0 (float) fconst_1 Push 1 (float) fconst_2 Push 2 (float) iconst_0 Push 0 (int) iconst_1 Push 1 (int) iconst_2 Push 2 (int) iconst_3 Push 3 (int) iconst_4 Push 4 (int) iconst_5 Push 5 (int) iconst_m1 Push ?(int) lconst_0 Push 0 (long) lconst_1 Push 1 (long) ldc x Push x (a constant int, float, or String) ldc_w x Push x (a constant int, float, or String) ldc2_w x Push x (a constant long or double) sipush n Push int between ?2,768 and 32767 A.3.4 Control Mnemonic Arguments Description areturn Return reference from method dreturn Return double from method freturn Return float from method goto label Branch always goto_w label Branch always to label if_acmpeq label Branch if a == b if_acmpne label Branch if a != b if_icmpeq label Branch if a > b if_icmpge label Branch if a >= b if_icmpgt label Branch if a > b if_icmple label Branch if a <= b if_icmplt label Branch if a < b if_icmpne label Branch if a != b ifeq label Branch if a == 0 ifge label Branch if a >= 0 ifgt label Branch if a > 0 ifle label Branch if a <= 0 iflt label Branch if a < 0 ifne label Branch if a != 0 ifnonnull label Branch if a is not null ifnull label Branch if a is null ireturn Return int from method jsr label Branch to label; push return location jsr_w label Jump to label lookupswitch tag1: label1 tag2: label2... default: labeln Branch to label1 on tag1, label2 on tag2, . . . , labeln otherwise lreturn Return long from method nop Do nothing ret n Branch to location in variable n return Return from method tableswitch n label1 label2 . . . default: labeln Branch to label1 on n, label2 on n+1, . . . , labeln otherwise A.3.5 Data Type Conversion Mnemonic Arguments Description d2f Convert double ab to float d2i Convert double ab to int d2l Convert double ab to long f2d Convert float a to double f2i Convert float a to int f2l Convert float a to long i2d Convert int a to double i2f Convert int a to float i2l Convert int a to long l2d Convert long ab to double l2f Convert long ab to float l2i Convert long ab to int A.3.6 Object Mnemonic Arguments Description checkcast class Throw exception if a is not an instance of class getfield class/field desc Push object field from object a getstatic class/field desc Push static field instanceof class Push 1 if a is class, 0 otherwise invokeinterface class/method desc n Invoke method through interface with n argument words invokespecial class/method desc Invoke method directly invokestatic class/method desc Invoke static method invokevirtual class/method desc Invoke method virtually new class Create new object of class putfield class/field desc Store a in object field putstatic class/field desc Store a in static field A.3.7 Stack Manipulation Mnemonic Arguments Description dup Duplicate a dup_x1 Duplicate a, insert under b dup_x2 Duplicate a, insert under c dup2 Duplicate ab dup2_x1 Duplicate ab, insert under c dup2_x2 Duplicate ab, insert under d pop Remove a pop2 Remove ab swap Swap a and b A.3.8 Synchronization Mnemonic Arguments Description monitorenter Gain control of monitor of a monitorexit Release monitor of a A.3.9 Variable Mnemonic Arguments Description aload n Push local variable n aload_0 Push local variable 0 aload_1 Push local variable 1 aload_2 Push local variable 2 aload_3 Push local variable 3 astore n Store a in local variable n astore_0 Store a in local variable 0 astore_1 Store a in local variable 1 astore_2 Store a in local variable 2 astore_3 Store a in local variable 3 dload n Push local variable n dload_0 Push local variable 0 dload_1 Push local variable 1 dload_2 Push local variable 2 dload_3 Push local variable 3 dstore n Store ab in local variable n dstore_0 Store ab in local variable 0 dstore_1 Store ab in local variable 1 dstore_2 Store ab in local variable 2 dstore_3 Store ab in local variable 3 fload n Push local variable n fload_0 Push local variable 0 fload_1 Push local variable 1 fload_2 Push local variable 2 fload_3 Push local variable 3 fstore n Store a in local variable n fstore_0 Store a in local variable 0 fstore_1 Store a in local variable 1 fstore_2 Store a in local variable 2 fstore_3 Store a in local variable 3 iinc n increment Increment local variable iload n Push local variable n iload_0 Push local variable 0 iload_1 Push local variable 1 iload_2 Push local variable 2 iload_3 Push local variable 3 istore n Store a in local variable n istore_0 Store a in local variable 0 istore_1 Store a in local variable 1 istore_2 Store a in local variable 2 istore_3 Store a in local variable 3 lload n Push local variable n lload_0 Push local variable 0 lload_1 Push local variable 1 lload_2 Push local variable 2 lload_3 Push local variable 3 lstore n Store ab in local variable n lstore_0 Store ab in local variable 0 lstore_1 Store ab in local variable 1 lstore_2 Store ab in local variable 2 lstore_3 Store ab in local variable 3 wide instruction arguments Like instruction, except using wider range of values