projects / apple / xnu.git / blame
| Commit | Line | Data |
|---|---|---|
| 91447636 A |
1 | /* |
| 2 | * Copyright (c) 2003 Apple Computer, Inc. All rights reserved. | |
| 3 | * | |
| 4 | * @APPLE_LICENSE_HEADER_START@ | |
| 5 | * | |
| 6 | * The contents of this file constitute Original Code as defined in and | |
| 7 | * are subject to the Apple Public Source License Version 1.1 (the | |
| 8 | * "License"). You may not use this file except in compliance with the | |
| 9 | * License. Please obtain a copy of the License at | |
| 10 | * http://www.apple.com/publicsource and read it before using this file. | |
| 11 | * | |
| 12 | * This Original Code and all software distributed under the License are | |
| 13 | * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 14 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 15 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 16 | * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the | |
| 17 | * License for the specific language governing rights and limitations | |
| 18 | * under the License. | |
| 19 | * | |
| 20 | * @APPLE_LICENSE_HEADER_END@ | |
| 21 | */ | |
| 22 | ||
| 23 | #define ASSEMBLER | |
| 24 | #include <sys/appleapiopts.h> | |
| 25 | #include <ppc/asm.h> | |
| 26 | #include <machine/cpu_capabilities.h> | |
| 27 | #include <machine/commpage.h> | |
| 28 | ||
| 29 | /* | |
| 30 | * WARNING: this code is written for 32-bit mode, and ported by the kernel if necessary | |
| 31 | * to 64-bit mode for use in the 64-bit commpage. This "port" consists of the following | |
| 32 | * simple transformations: | |
| 33 | * - all word compares are changed to doubleword | |
| 34 | * - all "srwi[.]" opcodes are changed to "srdi[.]" | |
| 35 | * Nothing else is done. For this to work, the following rules must be | |
| 36 | * carefully followed: | |
| 37 | * - do not use carry or overflow | |
| 38 | * - only use record mode if you are sure the results are mode-invariant | |
| 39 | * for example, all "andi." and almost all "rlwinm." are fine | |
| 40 | * - do not use "slwi", "slw", or "srw" | |
| 41 | * An imaginative programmer could break the porting model in other ways, but the above | |
| 42 | * are the most likely problem areas. It is perhaps surprising how well in practice | |
| 43 | * this simple method works. | |
| 44 | */ | |
| 45 | ||
| 46 | .text | |
| 47 | .align 2 | |
| 48 | ||
| 49 | ||
| 50 | /* ********************* | |
| 51 | * * M E M S E T _ 6 4 * | |
| 52 | * ********************* | |
| 53 | * | |
| 54 | * This is a subroutine called by Libc memset and _memset_pattern for large nonzero | |
| 55 | * operands (zero operands are funneled into bzero.) This version is for a | |
| 56 | * hypothetic processor that is 64-bit but not Altivec. | |
| 57 | * It is not optimized, since it would only be used during bringup. | |
| 58 | * | |
| 59 | * Registers at entry: | |
| 60 | * r4 = count of bytes to store (must be >= 32) | |
| 61 | * r8 = ptr to the 1st byte to store (16-byte aligned) | |
| 62 | * r9 = ptr to 16-byte pattern to store (16-byte aligned) | |
| 63 | * When we return: | |
| 64 | * r3 = not changed, since memset returns it | |
| 65 | * r4 = bytes remaining to store (will be <32) | |
| 66 | * r7 = not changed | |
| 67 | * r8 = ptr to next byte to store (still 16-byte aligned) | |
| 68 | * r12 = not changed (holds return value for memset) | |
| 69 | */ | |
| 70 | ||
| 71 | memset_64: | |
| 72 | srwi r0,r4,5 // get number of 32-byte chunks (>0) | |
| 73 | ld r10,0(r9) // load pattern | |
| 74 | ld r11,8(r9) | |
| 75 | rlwinm r4,r4,0,0x1F // mask down count | |
| 76 | mtctr r0 // set up loop count | |
| 77 | ||
| 78 | // Loop over 32-byte chunks. | |
| 79 | 1: | |
| 80 | std r10,0(r8) | |
| 81 | std r11,8(r8) | |
| 82 | std r10,16(r8) | |
| 83 | std r11,24(r8) | |
| 84 | addi r8,r8,32 | |
| 85 | bdnz++ 1b | |
| 86 | ||
| 87 | blr | |
| 88 | ||
| 89 | ||
| 90 | COMMPAGE_DESCRIPTOR(memset_64,_COMM_PAGE_MEMSET_PATTERN,k64Bit,kHasAltivec, \ | |
| 91 | kCommPageBoth+kPort32to64) |