1 /*******************************************************************************
3 * Module Name: utmath - Integer math support routines
6 ******************************************************************************/
8 /******************************************************************************
12 * Some or all of this work - Copyright (c) 1999 - 2003, Intel Corp.
13 * All rights reserved.
17 * 2.1. This is your license from Intel Corp. under its intellectual property
18 * rights. You may have additional license terms from the party that provided
19 * you this software, covering your right to use that party's intellectual
22 * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
23 * copy of the source code appearing in this file ("Covered Code") an
24 * irrevocable, perpetual, worldwide license under Intel's copyrights in the
25 * base code distributed originally by Intel ("Original Intel Code") to copy,
26 * make derivatives, distribute, use and display any portion of the Covered
27 * Code in any form, with the right to sublicense such rights; and
29 * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
30 * license (with the right to sublicense), under only those claims of Intel
31 * patents that are infringed by the Original Intel Code, to make, use, sell,
32 * offer to sell, and import the Covered Code and derivative works thereof
33 * solely to the minimum extent necessary to exercise the above copyright
34 * license, and in no event shall the patent license extend to any additions
35 * to or modifications of the Original Intel Code. No other license or right
36 * is granted directly or by implication, estoppel or otherwise;
38 * The above copyright and patent license is granted only if the following
43 * 3.1. Redistribution of Source with Rights to Further Distribute Source.
44 * Redistribution of source code of any substantial portion of the Covered
45 * Code or modification with rights to further distribute source must include
46 * the above Copyright Notice, the above License, this list of Conditions,
47 * and the following Disclaimer and Export Compliance provision. In addition,
48 * Licensee must cause all Covered Code to which Licensee contributes to
49 * contain a file documenting the changes Licensee made to create that Covered
50 * Code and the date of any change. Licensee must include in that file the
51 * documentation of any changes made by any predecessor Licensee. Licensee
52 * must include a prominent statement that the modification is derived,
53 * directly or indirectly, from Original Intel Code.
55 * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
56 * Redistribution of source code of any substantial portion of the Covered
57 * Code or modification without rights to further distribute source must
58 * include the following Disclaimer and Export Compliance provision in the
59 * documentation and/or other materials provided with distribution. In
60 * addition, Licensee may not authorize further sublicense of source of any
61 * portion of the Covered Code, and must include terms to the effect that the
62 * license from Licensee to its licensee is limited to the intellectual
63 * property embodied in the software Licensee provides to its licensee, and
64 * not to intellectual property embodied in modifications its licensee may
67 * 3.3. Redistribution of Executable. Redistribution in executable form of any
68 * substantial portion of the Covered Code or modification must reproduce the
69 * above Copyright Notice, and the following Disclaimer and Export Compliance
70 * provision in the documentation and/or other materials provided with the
73 * 3.4. Intel retains all right, title, and interest in and to the Original
76 * 3.5. Neither the name Intel nor any other trademark owned or controlled by
77 * Intel shall be used in advertising or otherwise to promote the sale, use or
78 * other dealings in products derived from or relating to the Covered Code
79 * without prior written authorization from Intel.
81 * 4. Disclaimer and Export Compliance
83 * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
84 * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
85 * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
86 * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
87 * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
88 * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
91 * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
92 * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
93 * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
94 * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
95 * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
96 * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
97 * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
100 * 4.3. Licensee shall not export, either directly or indirectly, any of this
101 * software or system incorporating such software without first obtaining any
102 * required license or other approval from the U. S. Department of Commerce or
103 * any other agency or department of the United States Government. In the
104 * event Licensee exports any such software from the United States or
105 * re-exports any such software from a foreign destination, Licensee shall
106 * ensure that the distribution and export/re-export of the software is in
107 * compliance with all laws, regulations, orders, or other restrictions of the
108 * U.S. Export Administration Regulations. Licensee agrees that neither it nor
109 * any of its subsidiaries will export/re-export any technical data, process,
110 * software, or service, directly or indirectly, to any country for which the
111 * United States government or any agency thereof requires an export license,
112 * other governmental approval, or letter of assurance, without first obtaining
113 * such license, approval or letter.
115 *****************************************************************************/
116 /* $DragonFly: src/sys/contrib/dev/acpica/Attic/utmath.c,v 1.1 2003/09/24 03:32:16 drhodus Exp $ */
124 #define _COMPONENT ACPI_UTILITIES
125 ACPI_MODULE_NAME ("utmath")
128 * Support for double-precision integer divide. This code is included here
129 * in order to support kernel environments where the double-precision math
130 * library is not available.
133 #ifndef ACPI_USE_NATIVE_DIVIDE
134 /*******************************************************************************
136 * FUNCTION: AcpiUtShortDivide
138 * PARAMETERS: InDividend - Pointer to the dividend
139 * Divisor - 32-bit divisor
140 * OutQuotient - Pointer to where the quotient is returned
141 * OutRemainder - Pointer to where the remainder is returned
143 * RETURN: Status (Checks for divide-by-zero)
145 * DESCRIPTION: Perform a short (maximum 64 bits divided by 32 bits)
146 * divide and modulo. The result is a 64-bit quotient and a
149 ******************************************************************************/
153 ACPI_INTEGER *InDividend,
155 ACPI_INTEGER *OutQuotient,
156 UINT32 *OutRemainder)
158 UINT64_OVERLAY Dividend;
159 UINT64_OVERLAY Quotient;
163 ACPI_FUNCTION_TRACE ("UtShortDivide");
165 Dividend.Full = *InDividend;
167 /* Always check for a zero divisor */
171 ACPI_REPORT_ERROR (("AcpiUtShortDivide: Divide by zero\n"));
172 return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO);
176 * The quotient is 64 bits, the remainder is always 32 bits,
177 * and is generated by the second divide.
179 ACPI_DIV_64_BY_32 (0, Dividend.Part.Hi, Divisor,
180 Quotient.Part.Hi, Remainder32);
181 ACPI_DIV_64_BY_32 (Remainder32, Dividend.Part.Lo, Divisor,
182 Quotient.Part.Lo, Remainder32);
184 /* Return only what was requested */
188 *OutQuotient = Quotient.Full;
192 *OutRemainder = Remainder32;
195 return_ACPI_STATUS (AE_OK);
199 /*******************************************************************************
201 * FUNCTION: AcpiUtDivide
203 * PARAMETERS: InDividend - Pointer to the dividend
204 * InDivisor - Pointer to the divisor
205 * OutQuotient - Pointer to where the quotient is returned
206 * OutRemainder - Pointer to where the remainder is returned
208 * RETURN: Status (Checks for divide-by-zero)
210 * DESCRIPTION: Perform a divide and modulo.
212 ******************************************************************************/
216 ACPI_INTEGER *InDividend,
217 ACPI_INTEGER *InDivisor,
218 ACPI_INTEGER *OutQuotient,
219 ACPI_INTEGER *OutRemainder)
221 UINT64_OVERLAY Dividend;
222 UINT64_OVERLAY Divisor;
223 UINT64_OVERLAY Quotient;
224 UINT64_OVERLAY Remainder;
225 UINT64_OVERLAY NormalizedDividend;
226 UINT64_OVERLAY NormalizedDivisor;
228 UINT64_OVERLAY Partial2;
229 UINT64_OVERLAY Partial3;
232 ACPI_FUNCTION_TRACE ("UtDivide");
235 /* Always check for a zero divisor */
239 ACPI_REPORT_ERROR (("AcpiUtDivide: Divide by zero\n"));
240 return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO);
243 Divisor.Full = *InDivisor;
244 Dividend.Full = *InDividend;
245 if (Divisor.Part.Hi == 0)
248 * 1) Simplest case is where the divisor is 32 bits, we can
249 * just do two divides
251 Remainder.Part.Hi = 0;
254 * The quotient is 64 bits, the remainder is always 32 bits,
255 * and is generated by the second divide.
257 ACPI_DIV_64_BY_32 (0, Dividend.Part.Hi, Divisor.Part.Lo,
258 Quotient.Part.Hi, Partial1);
259 ACPI_DIV_64_BY_32 (Partial1, Dividend.Part.Lo, Divisor.Part.Lo,
260 Quotient.Part.Lo, Remainder.Part.Lo);
266 * 2) The general case where the divisor is a full 64 bits
269 Quotient.Part.Hi = 0;
270 NormalizedDividend = Dividend;
271 NormalizedDivisor = Divisor;
273 /* Normalize the operands (shift until the divisor is < 32 bits) */
277 ACPI_SHIFT_RIGHT_64 (NormalizedDivisor.Part.Hi,
278 NormalizedDivisor.Part.Lo);
279 ACPI_SHIFT_RIGHT_64 (NormalizedDividend.Part.Hi,
280 NormalizedDividend.Part.Lo);
282 } while (NormalizedDivisor.Part.Hi != 0);
286 ACPI_DIV_64_BY_32 (NormalizedDividend.Part.Hi,
287 NormalizedDividend.Part.Lo,
288 NormalizedDivisor.Part.Lo,
289 Quotient.Part.Lo, Partial1);
292 * The quotient is always 32 bits, and simply requires adjustment.
293 * The 64-bit remainder must be generated.
295 Partial1 = Quotient.Part.Lo * Divisor.Part.Hi;
296 Partial2.Full = (ACPI_INTEGER) Quotient.Part.Lo * Divisor.Part.Lo;
297 Partial3.Full = (ACPI_INTEGER) Partial2.Part.Hi + Partial1;
299 Remainder.Part.Hi = Partial3.Part.Lo;
300 Remainder.Part.Lo = Partial2.Part.Lo;
302 if (Partial3.Part.Hi == 0)
304 if (Partial3.Part.Lo >= Dividend.Part.Hi)
306 if (Partial3.Part.Lo == Dividend.Part.Hi)
308 if (Partial2.Part.Lo > Dividend.Part.Lo)
311 Remainder.Full -= Divisor.Full;
317 Remainder.Full -= Divisor.Full;
321 Remainder.Full = Remainder.Full - Dividend.Full;
322 Remainder.Part.Hi = (UINT32) -((INT32) Remainder.Part.Hi);
323 Remainder.Part.Lo = (UINT32) -((INT32) Remainder.Part.Lo);
325 if (Remainder.Part.Lo)
332 /* Return only what was requested */
336 *OutQuotient = Quotient.Full;
340 *OutRemainder = Remainder.Full;
343 return_ACPI_STATUS (AE_OK);
348 /*******************************************************************************
350 * FUNCTION: AcpiUtShortDivide, AcpiUtDivide
352 * DESCRIPTION: Native versions of the UtDivide functions. Use these if either
353 * 1) The target is a 64-bit platform and therefore 64-bit
354 * integer math is supported directly by the machine.
355 * 2) The target is a 32-bit or 16-bit platform, and the
356 * double-precision integer math library is available to
357 * perform the divide.
359 ******************************************************************************/
363 ACPI_INTEGER *InDividend,
365 ACPI_INTEGER *OutQuotient,
366 UINT32 *OutRemainder)
369 ACPI_FUNCTION_TRACE ("UtShortDivide");
372 /* Always check for a zero divisor */
376 ACPI_REPORT_ERROR (("AcpiUtShortDivide: Divide by zero\n"));
377 return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO);
380 /* Return only what was requested */
384 *OutQuotient = *InDividend / Divisor;
388 *OutRemainder = (UINT32) *InDividend % Divisor;
391 return_ACPI_STATUS (AE_OK);
396 ACPI_INTEGER *InDividend,
397 ACPI_INTEGER *InDivisor,
398 ACPI_INTEGER *OutQuotient,
399 ACPI_INTEGER *OutRemainder)
401 ACPI_FUNCTION_TRACE ("UtDivide");
404 /* Always check for a zero divisor */
408 ACPI_REPORT_ERROR (("AcpiUtDivide: Divide by zero\n"));
409 return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO);
413 /* Return only what was requested */
417 *OutQuotient = *InDividend / *InDivisor;
421 *OutRemainder = *InDividend % *InDivisor;
424 return_ACPI_STATUS (AE_OK);