What's the primary difference between branch instruction and branch with link instruction? ARM?

assembly arm subroutine function-call
夢のの夢 picture 夢のの夢 · Oct 11, 2015 · Viewed 16.4k times · Source

From what I read, the branch with link is used to perform subroutine call and the registered link is copied back to PC.

Answer

Colin picture Colin · Oct 11, 2015

Branch with link BL copies the address of the next instruction (after the BL) into the link register. The branch instruction doesn't. BL would be used for a subroutine call, so when you want to return to where you were you can branch back to the link register.

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