1 /******************************************************************************
2  *
3  * Module Name: dtexpress.c - Support for integer expressions and labels
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include "aslcompiler.h"
45 #include "dtcompiler.h"
46 #include "dtparser.y.h"
47 
48 #define _COMPONENT          DT_COMPILER
49         ACPI_MODULE_NAME    ("dtexpress")
50 
51 
52 /* Local prototypes */
53 
54 static void
55 DtInsertLabelField (
56     DT_FIELD                *Field);
57 
58 static DT_FIELD *
59 DtLookupLabel (
60     char                    *Name);
61 
62 /* Global used for errors during parse and related functions */
63 
64 DT_FIELD                *Gbl_CurrentField;
65 
66 
67 /******************************************************************************
68  *
69  * FUNCTION:    DtResolveIntegerExpression
70  *
71  * PARAMETERS:  Field               - Field object with Integer expression
72  *              ReturnValue         - Where the integer is returned
73  *
74  * RETURN:      Status, and the resolved 64-bit integer value
75  *
76  * DESCRIPTION: Resolve an integer expression to a single value. Supports
77  *              both integer constants and labels.
78  *
79  *****************************************************************************/
80 
81 ACPI_STATUS
82 DtResolveIntegerExpression (
83     DT_FIELD                *Field,
84     UINT64                  *ReturnValue)
85 {
86     UINT64                  Result;
87 
88 
89     DbgPrint (ASL_DEBUG_OUTPUT, "Full Integer expression: %s\n",
90         Field->Value);
91 
92     Gbl_CurrentField = Field;
93 
94     Result = DtEvaluateExpression (Field->Value);
95     *ReturnValue = Result;
96     return (AE_OK);
97 }
98 
99 
100 /******************************************************************************
101  *
102  * FUNCTION:    DtDoOperator
103  *
104  * PARAMETERS:  LeftValue           - First 64-bit operand
105  *              Operator            - Parse token for the operator (EXPOP_*)
106  *              RightValue          - Second 64-bit operand
107  *
108  * RETURN:      64-bit result of the requested operation
109  *
110  * DESCRIPTION: Perform the various 64-bit integer math functions
111  *
112  *****************************************************************************/
113 
114 UINT64
115 DtDoOperator (
116     UINT64                  LeftValue,
117     UINT32                  Operator,
118     UINT64                  RightValue)
119 {
120     UINT64                  Result;
121 
122 
123     /* Perform the requested operation */
124 
125     switch (Operator)
126     {
127     case EXPOP_ONES_COMPLIMENT:
128 
129         Result = ~RightValue;
130         break;
131 
132     case EXPOP_LOGICAL_NOT:
133 
134         Result = !RightValue;
135         break;
136 
137     case EXPOP_MULTIPLY:
138 
139         Result = LeftValue * RightValue;
140         break;
141 
142     case EXPOP_DIVIDE:
143 
144         if (!RightValue)
145         {
146             DtError (ASL_ERROR, ASL_MSG_DIVIDE_BY_ZERO,
147                 Gbl_CurrentField, NULL);
148             return (0);
149         }
150         Result = LeftValue / RightValue;
151         break;
152 
153     case EXPOP_MODULO:
154 
155         if (!RightValue)
156         {
157             DtError (ASL_ERROR, ASL_MSG_DIVIDE_BY_ZERO,
158                 Gbl_CurrentField, NULL);
159             return (0);
160         }
161         Result = LeftValue % RightValue;
162         break;
163 
164     case EXPOP_ADD:
165         Result = LeftValue + RightValue;
166         break;
167 
168     case EXPOP_SUBTRACT:
169 
170         Result = LeftValue - RightValue;
171         break;
172 
173     case EXPOP_SHIFT_RIGHT:
174 
175         Result = LeftValue >> RightValue;
176         break;
177 
178     case EXPOP_SHIFT_LEFT:
179 
180         Result = LeftValue << RightValue;
181         break;
182 
183     case EXPOP_LESS:
184 
185         Result = LeftValue < RightValue;
186         break;
187 
188     case EXPOP_GREATER:
189 
190         Result = LeftValue > RightValue;
191         break;
192 
193     case EXPOP_LESS_EQUAL:
194 
195         Result = LeftValue <= RightValue;
196         break;
197 
198     case EXPOP_GREATER_EQUAL:
199 
200         Result = LeftValue >= RightValue;
201         break;
202 
203     case EXPOP_EQUAL:
204 
205         Result = LeftValue == RightValue;
206         break;
207 
208     case EXPOP_NOT_EQUAL:
209 
210         Result = LeftValue != RightValue;
211         break;
212 
213     case EXPOP_AND:
214 
215         Result = LeftValue & RightValue;
216         break;
217 
218     case EXPOP_XOR:
219 
220         Result = LeftValue ^ RightValue;
221         break;
222 
223     case EXPOP_OR:
224 
225         Result = LeftValue | RightValue;
226         break;
227 
228     case EXPOP_LOGICAL_AND:
229 
230         Result = LeftValue && RightValue;
231         break;
232 
233     case EXPOP_LOGICAL_OR:
234 
235         Result = LeftValue || RightValue;
236         break;
237 
238    default:
239 
240         /* Unknown operator */
241 
242         DtFatal (ASL_MSG_INVALID_EXPRESSION,
243             Gbl_CurrentField, NULL);
244         return (0);
245     }
246 
247     DbgPrint (ASL_DEBUG_OUTPUT,
248         "IntegerEval: (%8.8X%8.8X %s %8.8X%8.8X) = %8.8X%8.8X\n",
249         ACPI_FORMAT_UINT64 (LeftValue),
250         DtGetOpName (Operator),
251         ACPI_FORMAT_UINT64 (RightValue),
252         ACPI_FORMAT_UINT64 (Result));
253 
254     return (Result);
255 }
256 
257 
258 /******************************************************************************
259  *
260  * FUNCTION:    DtResolveLabel
261  *
262  * PARAMETERS:  LabelString         - Contains the label
263  *
264  * RETURN:      Table offset associated with the label
265  *
266  * DESCRIPTION: Lookup a lable and return its value.
267  *
268  *****************************************************************************/
269 
270 UINT64
271 DtResolveLabel (
272     char                    *LabelString)
273 {
274     DT_FIELD                *LabelField;
275 
276 
277     DbgPrint (ASL_DEBUG_OUTPUT, "Resolve Label: %s\n", LabelString);
278 
279     /* Resolve a label reference to an integer (table offset) */
280 
281     if (*LabelString != '$')
282     {
283         return (0);
284     }
285 
286     LabelField = DtLookupLabel (LabelString);
287     if (!LabelField)
288     {
289         DtError (ASL_ERROR, ASL_MSG_UNKNOWN_LABEL,
290             Gbl_CurrentField, LabelString);
291         return (0);
292     }
293 
294     /* All we need from the label is the offset in the table */
295 
296     DbgPrint (ASL_DEBUG_OUTPUT, "Resolved Label: 0x%8.8X\n",
297         LabelField->TableOffset);
298 
299     return (LabelField->TableOffset);
300 }
301 
302 
303 /******************************************************************************
304  *
305  * FUNCTION:    DtDetectAllLabels
306  *
307  * PARAMETERS:  FieldList           - Field object at start of generic list
308  *
309  * RETURN:      None
310  *
311  * DESCRIPTION: Detect all labels in a list of "generic" opcodes (such as
312  *              a UEFI table.) and insert them into the global label list.
313  *
314  *****************************************************************************/
315 
316 void
317 DtDetectAllLabels (
318     DT_FIELD                *FieldList)
319 {
320     ACPI_DMTABLE_INFO       *Info;
321     DT_FIELD                *GenericField;
322     UINT32                  TableOffset;
323 
324 
325     TableOffset = Gbl_CurrentTableOffset;
326     GenericField = FieldList;
327 
328     /*
329      * Process all "Label:" fields within the parse tree. We need
330      * to know the offsets for all labels before we can compile
331      * the parse tree in order to handle forward references. Traverse
332      * tree and get/set all field lengths of all operators in order to
333      * determine the label offsets.
334      */
335     while (GenericField)
336     {
337         Info = DtGetGenericTableInfo (GenericField->Name);
338         if (Info)
339         {
340             /* Maintain table offsets */
341 
342             GenericField->TableOffset = TableOffset;
343             TableOffset += DtGetFieldLength (GenericField, Info);
344 
345             /* Insert all labels in the global label list */
346 
347             if (Info->Opcode == ACPI_DMT_LABEL)
348             {
349                 DtInsertLabelField (GenericField);
350             }
351         }
352 
353         GenericField = GenericField->Next;
354     }
355 }
356 
357 
358 /******************************************************************************
359  *
360  * FUNCTION:    DtInsertLabelField
361  *
362  * PARAMETERS:  Field               - Field object with Label to be inserted
363  *
364  * RETURN:      None
365  *
366  * DESCRIPTION: Insert a label field into the global label list
367  *
368  *****************************************************************************/
369 
370 static void
371 DtInsertLabelField (
372     DT_FIELD                *Field)
373 {
374 
375     DbgPrint (ASL_DEBUG_OUTPUT,
376         "DtInsertLabelField: Found Label : %s at output table offset %X\n",
377         Field->Value, Field->TableOffset);
378 
379     Field->NextLabel = Gbl_LabelList;
380     Gbl_LabelList = Field;
381 }
382 
383 
384 /******************************************************************************
385  *
386  * FUNCTION:    DtLookupLabel
387  *
388  * PARAMETERS:  Name                - Label to be resolved
389  *
390  * RETURN:      Field object associated with the label
391  *
392  * DESCRIPTION: Lookup a label in the global label list. Used during the
393  *              resolution of integer expressions.
394  *
395  *****************************************************************************/
396 
397 static DT_FIELD *
398 DtLookupLabel (
399     char                    *Name)
400 {
401     DT_FIELD                *LabelField;
402 
403 
404     /* Skip a leading $ */
405 
406     if (*Name == '$')
407     {
408         Name++;
409     }
410 
411     /* Search global list */
412 
413     LabelField = Gbl_LabelList;
414     while (LabelField)
415     {
416         if (!ACPI_STRCMP (Name, LabelField->Value))
417         {
418             return (LabelField);
419         }
420         LabelField = LabelField->NextLabel;
421     }
422 
423     return (NULL);
424 }
425