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 
151         Result = LeftValue / RightValue;
152         break;
153 
154     case EXPOP_MODULO:
155 
156         if (!RightValue)
157         {
158             DtError (ASL_ERROR, ASL_MSG_DIVIDE_BY_ZERO,
159                 Gbl_CurrentField, NULL);
160             return (0);
161         }
162 
163         Result = LeftValue % RightValue;
164         break;
165 
166     case EXPOP_ADD:
167         Result = LeftValue + RightValue;
168         break;
169 
170     case EXPOP_SUBTRACT:
171 
172         Result = LeftValue - RightValue;
173         break;
174 
175     case EXPOP_SHIFT_RIGHT:
176 
177         Result = LeftValue >> RightValue;
178         break;
179 
180     case EXPOP_SHIFT_LEFT:
181 
182         Result = LeftValue << RightValue;
183         break;
184 
185     case EXPOP_LESS:
186 
187         Result = LeftValue < RightValue;
188         break;
189 
190     case EXPOP_GREATER:
191 
192         Result = LeftValue > RightValue;
193         break;
194 
195     case EXPOP_LESS_EQUAL:
196 
197         Result = LeftValue <= RightValue;
198         break;
199 
200     case EXPOP_GREATER_EQUAL:
201 
202         Result = LeftValue >= RightValue;
203         break;
204 
205     case EXPOP_EQUAL:
206 
207         Result = LeftValue == RightValue;
208         break;
209 
210     case EXPOP_NOT_EQUAL:
211 
212         Result = LeftValue != RightValue;
213         break;
214 
215     case EXPOP_AND:
216 
217         Result = LeftValue & RightValue;
218         break;
219 
220     case EXPOP_XOR:
221 
222         Result = LeftValue ^ RightValue;
223         break;
224 
225     case EXPOP_OR:
226 
227         Result = LeftValue | RightValue;
228         break;
229 
230     case EXPOP_LOGICAL_AND:
231 
232         Result = LeftValue && RightValue;
233         break;
234 
235     case EXPOP_LOGICAL_OR:
236 
237         Result = LeftValue || RightValue;
238         break;
239 
240    default:
241 
242         /* Unknown operator */
243 
244         DtFatal (ASL_MSG_INVALID_EXPRESSION,
245             Gbl_CurrentField, NULL);
246         return (0);
247     }
248 
249     DbgPrint (ASL_DEBUG_OUTPUT,
250         "IntegerEval: (%8.8X%8.8X %s %8.8X%8.8X) = %8.8X%8.8X\n",
251         ACPI_FORMAT_UINT64 (LeftValue),
252         DtGetOpName (Operator),
253         ACPI_FORMAT_UINT64 (RightValue),
254         ACPI_FORMAT_UINT64 (Result));
255 
256     return (Result);
257 }
258 
259 
260 /******************************************************************************
261  *
262  * FUNCTION:    DtResolveLabel
263  *
264  * PARAMETERS:  LabelString         - Contains the label
265  *
266  * RETURN:      Table offset associated with the label
267  *
268  * DESCRIPTION: Lookup a lable and return its value.
269  *
270  *****************************************************************************/
271 
272 UINT64
273 DtResolveLabel (
274     char                    *LabelString)
275 {
276     DT_FIELD                *LabelField;
277 
278 
279     DbgPrint (ASL_DEBUG_OUTPUT, "Resolve Label: %s\n", LabelString);
280 
281     /* Resolve a label reference to an integer (table offset) */
282 
283     if (*LabelString != '$')
284     {
285         return (0);
286     }
287 
288     LabelField = DtLookupLabel (LabelString);
289     if (!LabelField)
290     {
291         DtError (ASL_ERROR, ASL_MSG_UNKNOWN_LABEL,
292             Gbl_CurrentField, LabelString);
293         return (0);
294     }
295 
296     /* All we need from the label is the offset in the table */
297 
298     DbgPrint (ASL_DEBUG_OUTPUT, "Resolved Label: 0x%8.8X\n",
299         LabelField->TableOffset);
300 
301     return (LabelField->TableOffset);
302 }
303 
304 
305 /******************************************************************************
306  *
307  * FUNCTION:    DtDetectAllLabels
308  *
309  * PARAMETERS:  FieldList           - Field object at start of generic list
310  *
311  * RETURN:      None
312  *
313  * DESCRIPTION: Detect all labels in a list of "generic" opcodes (such as
314  *              a UEFI table.) and insert them into the global label list.
315  *
316  *****************************************************************************/
317 
318 void
319 DtDetectAllLabels (
320     DT_FIELD                *FieldList)
321 {
322     ACPI_DMTABLE_INFO       *Info;
323     DT_FIELD                *GenericField;
324     UINT32                  TableOffset;
325 
326 
327     TableOffset = Gbl_CurrentTableOffset;
328     GenericField = FieldList;
329 
330     /*
331      * Process all "Label:" fields within the parse tree. We need
332      * to know the offsets for all labels before we can compile
333      * the parse tree in order to handle forward references. Traverse
334      * tree and get/set all field lengths of all operators in order to
335      * determine the label offsets.
336      */
337     while (GenericField)
338     {
339         Info = DtGetGenericTableInfo (GenericField->Name);
340         if (Info)
341         {
342             /* Maintain table offsets */
343 
344             GenericField->TableOffset = TableOffset;
345             TableOffset += DtGetFieldLength (GenericField, Info);
346 
347             /* Insert all labels in the global label list */
348 
349             if (Info->Opcode == ACPI_DMT_LABEL)
350             {
351                 DtInsertLabelField (GenericField);
352             }
353         }
354 
355         GenericField = GenericField->Next;
356     }
357 }
358 
359 
360 /******************************************************************************
361  *
362  * FUNCTION:    DtInsertLabelField
363  *
364  * PARAMETERS:  Field               - Field object with Label to be inserted
365  *
366  * RETURN:      None
367  *
368  * DESCRIPTION: Insert a label field into the global label list
369  *
370  *****************************************************************************/
371 
372 static void
373 DtInsertLabelField (
374     DT_FIELD                *Field)
375 {
376 
377     DbgPrint (ASL_DEBUG_OUTPUT,
378         "DtInsertLabelField: Found Label : %s at output table offset %X\n",
379         Field->Value, Field->TableOffset);
380 
381     Field->NextLabel = Gbl_LabelList;
382     Gbl_LabelList = Field;
383 }
384 
385 
386 /******************************************************************************
387  *
388  * FUNCTION:    DtLookupLabel
389  *
390  * PARAMETERS:  Name                - Label to be resolved
391  *
392  * RETURN:      Field object associated with the label
393  *
394  * DESCRIPTION: Lookup a label in the global label list. Used during the
395  *              resolution of integer expressions.
396  *
397  *****************************************************************************/
398 
399 static DT_FIELD *
400 DtLookupLabel (
401     char                    *Name)
402 {
403     DT_FIELD                *LabelField;
404 
405 
406     /* Skip a leading $ */
407 
408     if (*Name == '$')
409     {
410         Name++;
411     }
412 
413     /* Search global list */
414 
415     LabelField = Gbl_LabelList;
416     while (LabelField)
417     {
418         if (!strcmp (Name, LabelField->Value))
419         {
420             return (LabelField);
421         }
422 
423         LabelField = LabelField->NextLabel;
424     }
425 
426     return (NULL);
427 }
428