projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| dfc34940 SM |
1 | /* |
| 2 | * "memset" implementation for SH4 | |
| 3 | * | |
| 4 | * Copyright (C) 1999 Niibe Yutaka | |
| 5 | * Copyright (c) 2009 STMicroelectronics Limited | |
| 6 | * Author: Stuart Menefy <stuart.menefy:st.com> | |
| 7 | */ | |
| 8 | ||
| 9 | /* | |
| 10 | * void *memset(void *s, int c, size_t n); | |
| 11 | */ | |
| 12 | ||
| 13 | #include <linux/linkage.h> | |
| 14 | ||
| 15 | ENTRY(memset) | |
| 16 | mov #12,r0 | |
| 17 | add r6,r4 | |
| 18 | cmp/gt r6,r0 | |
| 19 | bt/s 40f ! if it's too small, set a byte at once | |
| 20 | mov r4,r0 | |
| 21 | and #3,r0 | |
| 22 | cmp/eq #0,r0 | |
| 23 | bt/s 2f ! It's aligned | |
| 24 | sub r0,r6 | |
| 25 | 1: | |
| 26 | dt r0 | |
| 27 | bf/s 1b | |
| 28 | mov.b r5,@-r4 | |
| 29 | 2: ! make VVVV | |
| 30 | extu.b r5,r5 | |
| 31 | swap.b r5,r0 ! V0 | |
| 32 | or r0,r5 ! VV | |
| 33 | swap.w r5,r0 ! VV00 | |
| 34 | or r0,r5 ! VVVV | |
| 35 | ||
| 36 | ! Check if enough bytes need to be copied to be worth the big loop | |
| 37 | mov #0x40, r0 ! (MT) | |
| 38 | cmp/gt r6,r0 ! (MT) 64 > len => slow loop | |
| 39 | ||
| 40 | bt/s 22f | |
| 41 | mov r6,r0 | |
| 42 | ||
| 43 | ! align the dst to the cache block size if necessary | |
| 44 | mov r4, r3 | |
| 45 | mov #~(0x1f), r1 | |
| 46 | ||
| 47 | and r3, r1 | |
| 48 | cmp/eq r3, r1 | |
| 49 | ||
| 50 | bt/s 11f ! dst is already aligned | |
| 51 | sub r1, r3 ! r3-r1 -> r3 | |
| 52 | shlr2 r3 ! number of loops | |
| 53 | ||
| 54 | 10: mov.l r5,@-r4 | |
| 55 | dt r3 | |
| 56 | bf/s 10b | |
| 57 | add #-4, r6 | |
| 58 | ||
| 59 | 11: ! dst is 32byte aligned | |
| 60 | mov r6,r2 | |
| 61 | mov #-5,r0 | |
| 62 | shld r0,r2 ! number of loops | |
| 63 | ||
| 64 | add #-32, r4 | |
| 65 | mov r5, r0 | |
| 66 | 12: | |
| 67 | movca.l r0,@r4 | |
| 68 | mov.l r5,@(4, r4) | |
| 69 | mov.l r5,@(8, r4) | |
| 70 | mov.l r5,@(12,r4) | |
| 71 | mov.l r5,@(16,r4) | |
| 72 | mov.l r5,@(20,r4) | |
| 73 | add #-0x20, r6 | |
| 74 | mov.l r5,@(24,r4) | |
| 75 | dt r2 | |
| 76 | mov.l r5,@(28,r4) | |
| 77 | bf/s 12b | |
| 78 | add #-32, r4 | |
| 79 | ||
| 80 | add #32, r4 | |
| 81 | mov #8, r0 | |
| 82 | cmp/ge r0, r6 | |
| 83 | bf 40f | |
| 84 | ||
| 85 | mov r6,r0 | |
| 86 | 22: | |
| 87 | shlr2 r0 | |
| 88 | shlr r0 ! r0 = r6 >> 3 | |
| 89 | 3: | |
| 90 | dt r0 | |
| 91 | mov.l r5,@-r4 ! set 8-byte at once | |
| 92 | bf/s 3b | |
| 93 | mov.l r5,@-r4 | |
| 94 | ! | |
| 95 | mov #7,r0 | |
| 96 | and r0,r6 | |
| 97 | ||
| 98 | ! fill bytes (length may be zero) | |
| 99 | 40: tst r6,r6 | |
| 100 | bt 5f | |
| 101 | 4: | |
| 102 | dt r6 | |
| 103 | bf/s 4b | |
| 104 | mov.b r5,@-r4 | |
| 105 | 5: | |
| 106 | rts | |
| 107 | mov r4,r0 |