A branch is an instruction in a computer program that can cause a computer to begin executing a different instruction sequence and thus deviate from its default behavior of executing instructions in order. Branch (or ''branching'', ''branched'') may also refer to the act of switching execution to a different instruction sequence as a result of executing a branch instruction. A branch instruction can be either an ''unconditional branch'', which always results in branching, or a ''conditional branch'', which may or may not cause branching, depending on some condition. Branch instructions are used to implement control flow in program loops and conditionals (i.e., executing a particular sequence of instructions only if certain conditions are satisfied). ==Implementation== The term ''branch'' can be used when referring to programs in high level languages as well as program written in machine code or assembly language. In high-level programming languages, branches usually take the form of conditional statements of various forms that encapsulate the instruction sequence that will be executed if the conditions are satisfied. Unconditional branch instructions such as GOTO are used to unconditionally "jump" to (begin execution of) a different instruction sequence. Machine level branch instructions are sometimes called ''jump'' instructions. Machine level jump instructions typically have ''unconditional'' and ''conditional'' forms where the latter may be ''taken'' or ''not taken'' depending on some condition. The truthness of this condition is typically evaluated and temporarily stored by some previous instruction (though not necessarily the one ''immediately'' before) and then used such as in ''jump if overflow-flag set''. This temporary information is often stored in a flag register but may also be located elsewhere. There are also machines (or particular instructions) where the condition may be checked by the jump instruction itself, such as ''branch 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Branch (computer science)」の詳細全文を読む
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