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divsl

Signed divide long, with remainder 68020

Divides a long by a long, signed, putting the quotient in one data register and the remainder in another.

Size .l68020 only: select opt p=68020 before any code or data

XNZVC –●●●0
  • ● set from the result
  • 0 always 0
  • – not changed

Forms

Operands

<ea>
An operand using one of the addressing modes listed for this form. The list determines whether it can be a register, memory or an immediate value. With opt p=68020, an allowed d(An,Xn) or d(PC,Xn) mode also permits the corresponding 68020 indexed and memory indirect forms. See 68020 addressing. More
Dr:Dq
A remainder register followed by a quotient register, for example d2:d1. For divs.l and divu.l, both supply the 64-bit dividend, high long first. For divsl.l and divul.l, only Dq supplies the 32-bit dividend. The quotient replaces Dq and the remainder replaces Dr. More
#imm
An immediate value written after #: a number, character or label, such as #10, #$FF or #'a'. It must fit the operation’s size: byte -128 to 255, word -32768 to 65535, or long -2147483648 to 4294967295; signed and unsigned spellings are accepted. More

In divsl.l <ea>, Dr:Dq, Dq supplies the dividend. The old value of Dr is not used. The quotient replaces Dq and the remainder replaces Dr. The remainder has the dividend’s sign: -7 divided by 2 gives quotient -3 and remainder -1.

Use different registers to keep both results. If Dr and Dq name the same register, only the quotient remains. This uses the same 32-bit dividend as the single-register form of divs.l. The register-pair form of divs.l takes a 64-bit dividend instead.

A zero divisor raises a division-by-zero exception through vector 5 at $14. The only signed 32-bit quotient overflow, -2147483648 divided by -1, sets V and leaves the registers unchanged. Otherwise V is cleared and N and Z describe the quotient. C is cleared and X is unchanged.

opt p=68020
* --- A quotient and a remainder of 32 bits ---
move.l #-100007, d2 ; the number to divide
divsl.l #10, d1:d2 ; d2 = -10000, and the remainder has its sign: d1 = -7