CMPQ TOP, $-1		/* return value == -1? */
	JEQ fsread_checkfd	/* return value = -1 */
	TESTQ TOP, TOP		/* check if read return value == 0 */
	JNZ fsread_continue
fsread_checkfd:
	MOVQ 32(SP), CX		/* read return value == 0, check if fd is stdin */
	TESTQ CX, CX
	JNZ fsread_continue
	/* and fd == 0, terminate */
	ADDQ $40, SP
	/* TODO
	 * this should have been JMP terminate(SB), but it is raising a #GP error.
	 * CALL terminate(SB) works fine.
	 * Would have to dig through the amd64 manuals and
	 * https://www.felixcloutier.com/x86/jmp to figure out why.
	 * until then, use the label to jump to

JMP to a label: JMP _fthterminate
2011b8 4883c428 (644)   ADDQ    $40,SP
2011bc e9d0fcffff       (493)   JMP     ,200e91
2011c1 4883c428 (656)   ADDQ    $40,SP

JMP to symbol: JMP terminate(SB)
2011b8 4883c428 (645)   ADDQ    $40,SP
2011bc ff2425910e2000   (654)   JMP     ,terminate+0(SB)
2011c3 4883c428 (657)   ADDQ    $40,SP

CALL to symbol: CALL terminate(SB)
2011b8 4883c428 (645)   ADDQ    $40,SP
2011bc e8d0fcffff       (655)   CALL    ,200e91+terminate
2011c1 4883c428 (657)   ADDQ    $40,SP
	JMP _fthterminate
	 */
	JMP fthdump(SB)

fsread_continue:
	ADDQ $40, SP
	NEXT