ifgt <label><label> is a label name. To define the location of the label, use the <label> name followed by a colon:
<label>:<label> then becomes associated the address of the following instruction. Labels can only be assigned one location in a method. On the other hand, a single <label> can be the target of multiple branch instructions.
Stack Before
Description After value ... ...
ifgt pops the top int off the operand stack. If the int is greater than zero, execution branches to the address (pc + branchoffset), where pc is the address of the ifgt opcode in the bytecode and branchoffset is a 16-bit signed integer parameter following the ifgt opcode in the bytecode. If the int on the stack does is less than or equal to zero, execution continues at the next instruction.
If you are using Jasmin, branchoffset is computed for you from the address of <label>.
Example
iload_1 ; push the int value in local variable 1 onto the stack ifgt Label ; if the value on the stack is greater than zero, jump to Label return ; return if local variable 1 is less than or equal to zero Label: ; execution continues here if local variable 1 is greater than zero...Bytecode
Type | Description |
u1 | ifgt opcode = 0x9D (157) |
s2 | branchoffset |
ifnull, ifeq, ifle, ifne, ifnonnull, iflt, ifge
Notes
Addresses are measured in bytes from the start of the bytecode (i.e. address 0 is the first byte in the bytecode of the currently executing method).