KOS_OP_CHECK_COMPARE

• Style: EXTRA (CMP, COUNT, LABEL, RAW). Row = KosCompare selector, operand count, target pc, negate flag.

• Stack: [..., a1, ..., aN] → [...]. Chain-compare the top COUNT operands under the selector, negated when the negate flag is set; jump to LABEL when the chain fails. The operands are dropped either way. Raises TypeError when COUNT < 2.

• Invariants: Selector is a valid KosCompare ordinal. The richcompare six (LT/LE/EQ/NE/GT/GE, ordinals 0-5, matching CPython’s Py_LT..Py_GE) chain over any COUNT; IS, IS_NOT, IN and NOT_IN require COUNT == 2; IS_INSTANCE and IS_SUBCLASS take any COUNT >= 2.

• Compiler form: Produced by Compiler.compress fusing OBJECT_COMPARE + JUMP_FALSE into one instruction, and OBJECT_COMPARE + JUMP_TRUE into the same with the flag set. Never emitted directly by specials.

Example: Branch unless 1 < x < 100. Selector LT = 0.

index	opcode	arg	arg view	comment
0	CONST	0	0 (1)	stack: […, 1]
1	FAST	0	0 (x)	stack: […, 1, x]
2	CONST	1	1 (100)	stack: […, 1, x, 100]
3	CHECK_COMPARE	0	(LT, 3, -> 6, 0)	jump to 6 unless 1 < x < 100