What is a JCC instruction in x86

Question

I only know instructions, such as je, jnl, etc., in the x86 AT & T syntax.

What does jcc mean? Any transition instructions?

Answer 1

ccstands for condition code.

JccIt is not a separate instruction, it simply describes the transition mnemonics , which checks the condition code before the transition.

JNE, for example, checks the condition code before proceeding.

A typical case is to make a comparison (which sets CC), and then use one of the jump mnemonics.

, AND, OR, XOR, , (, , CMP).

Answer 2

CC . FLAGS, JECXZ, Intel Jcc Jcc insn set ref manual entry.

, Agner Fog, JECXZ , -.

?

, .

x86 : LOOP/LOOPcc. LOOPE LOOPNE - , . ( LOOP, )

Jcc JMP , (, jmp *rax AT & T). , . CALL RET .

XBEGIN , XEND, , .

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"cc", FLAGS, : SETcc CMOVcc. , Jcc, FLAGS - , . , .

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x86:

GNU C "cc", , inline-asm . ( x86 x86-64: clobber "cc". (, ARM) x86 , , gcc x86, , , , , "cc" clobber.)