Lines Matching +full:half +full:- +full:bit

1 /* SPDX-License-Identifier: GPL-2.0 */
3 /*---------------------------------------------------------------------------+
10  |                       Australia.  E-mail [email protected]               |
20  |    Return value is the tag of the answer, or-ed with FPU_Exception if     |
21  |    one was raised, or -1 on internal error.                               |
26  +---------------------------------------------------------------------------*/
28 /*---------------------------------------------------------------------------+
32  |  %eax:%ebx  64 bit significand                                            |
33  |  %edx       32 bit extension of the significand                           |
47  |   must be non-zero.                                                       |
48  |   If the significand extension is non-zero then the significand is        |
50  |   greater than zero and less than one ls bit of the significand.          |
52  |   non-zero values:                                                        |
54  |                                 bit smaller than the magnitude of the     |
56  |         exactly 0x80000000  <=> the significand is exactly 1/2 an ls bit  |
60  |                                 bit smaller than the magnitude of the     |
63  +---------------------------------------------------------------------------*/
65 /*---------------------------------------------------------------------------+
70  |  a real FPU. These require a bit more thought because at this stage the   |
73  +---------------------------------------------------------------------------*/
90 /*	Make the code re-entrant by putting
96 /*	Not re-entrant, so we can gain speed by putting
138 	jle	L_Make_denorm			/* The number is a de-normal */
140 	movb	$0,FPU_denormal			/* 0 -> not a de-normal */
171 /* Round etc to 24 bit precision */
184 	cmpl	RC_DOWN,%ecx		/* Towards -infinity */
210 	/* Do rounding of the 24th bit if needed (nearest or even) */
214 	jc	LCheck_truncate_24	/* less than half, no increment needed */
216 	jne	LGreater_Half_24	/* greater than half, increment needed */
218 	/* Possibly half, we need to check the ls bits */
220 	jnz	LGreater_Half_24	/* greater than half, increment needed */
223 	jnz	LGreater_Half_24	/* greater than half, increment needed */
225 	/* Exactly half, increment only if 24th bit is 1 (round to even) */
229 LGreater_Half_24:			/* Rounding: increment at the 24th bit */
251 /* Round etc to 53 bit precision */
264 	cmpl	RC_DOWN,%ecx		/* Towards -infinity */
289 	/* Do rounding of the 53rd bit if needed (nearest or even) */
293 	jc	LCheck_truncate_53	/* less than half, no increment needed */
295 	jnz	LGreater_Half_53	/* greater than half, increment needed */
297 	/* Possibly half, we need to check the ls bits */
299 	jnz	LGreater_Half_53	/* greater than half, increment needed */
301 	/* Exactly half, increment only if 53rd bit is 1 (round to even) */
305 LGreater_Half_53:			/* Rounding: increment at the 53rd bit */
325 /* Round etc to 64 bit precision */
338 	cmpl	RC_DOWN,%ecx		/* Towards -infinity */
367 	/* Now test for round-to-even */
445  * round-up.
493  *   is for a small de-normalising shift.
498 	setne	%ch		/* Save whether %edx is non-zero */
533 /* Exactly 64 bit shift */
550 /* This is easy, %eax must be non-zero, so.. */
563 /* Undo the de-normalisation. */
645 	/* The number may have been changed to a non-denormal */
707 	mov	$-1,%eax