projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| 97f98500 HT |
1 | /** @file\r |
| 2 | 64-bit Math Worker Function.\r | |
| 3 | The 32-bit versions of C compiler generate calls to library routines\r | |
| 4 | to handle 64-bit math. These functions use non-standard calling conventions.\r | |
| 5 | \r | |
| 2ac68e8b | 6 | Copyright (c) 2014, Intel Corporation. All rights reserved.<BR>\r |
| 97f98500 HT |
7 | This program and the accompanying materials\r |
| 8 | are licensed and made available under the terms and conditions of the BSD License\r | |
| 9 | which accompanies this distribution. The full text of the license may be found at\r | |
| 10 | http://opensource.org/licenses/bsd-license.php\r | |
| 11 | \r | |
| 12 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
| 13 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
| 14 | \r | |
| 15 | **/\r | |
| 16 | \r | |
| 17 | \r | |
| 18 | /*\r | |
| 19 | * Shifts a 64-bit signed value left by a particular number of bits.\r | |
| 20 | */\r | |
| 21 | __declspec(naked) void __cdecl _allshl (void)\r | |
| 22 | {\r | |
| 23 | _asm {\r | |
| 24 | ;\r | |
| 25 | ; Handle shifting of 64 or more bits (return 0)\r | |
| 26 | ;\r | |
| 27 | cmp cl, 64\r | |
| 28 | jae short ReturnZero\r | |
| 29 | \r | |
| 30 | ;\r | |
| 31 | ; Handle shifting of between 0 and 31 bits\r | |
| 32 | ;\r | |
| 2ac68e8b | 33 | cmp cl, 32\r |
| 97f98500 HT |
34 | jae short More32\r |
| 35 | shld edx, eax, cl\r | |
| 36 | shl eax, cl\r | |
| 37 | ret\r | |
| 38 | \r | |
| 39 | ;\r | |
| 40 | ; Handle shifting of between 32 and 63 bits\r | |
| 41 | ;\r | |
| 42 | More32:\r | |
| 43 | mov edx, eax\r | |
| 44 | xor eax, eax\r | |
| 45 | and cl, 31\r | |
| 46 | shl edx, cl\r | |
| 47 | ret\r | |
| 48 | \r | |
| 49 | ReturnZero:\r | |
| 50 | xor eax,eax\r | |
| 51 | xor edx,edx\r | |
| 52 | ret\r | |
| 53 | }\r | |
| 54 | }\r |