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Diffstat (limited to 'arch/alpha/lib/ev67-strlen_user.S')
| -rw-r--r-- | arch/alpha/lib/ev67-strlen_user.S | 107 |
1 files changed, 0 insertions, 107 deletions
diff --git a/arch/alpha/lib/ev67-strlen_user.S b/arch/alpha/lib/ev67-strlen_user.S deleted file mode 100644 index 57e0d77b81a6..000000000000 --- a/arch/alpha/lib/ev67-strlen_user.S +++ /dev/null | |||
| @@ -1,107 +0,0 @@ | |||
| 1 | /* | ||
| 2 | * arch/alpha/lib/ev67-strlen_user.S | ||
| 3 | * 21264 version contributed by Rick Gorton <rick.gorton@api-networks.com> | ||
| 4 | * | ||
| 5 | * Return the length of the string including the NULL terminator | ||
| 6 | * (strlen+1) or zero if an error occurred. | ||
| 7 | * | ||
| 8 | * In places where it is critical to limit the processing time, | ||
| 9 | * and the data is not trusted, strnlen_user() should be used. | ||
| 10 | * It will return a value greater than its second argument if | ||
| 11 | * that limit would be exceeded. This implementation is allowed | ||
| 12 | * to access memory beyond the limit, but will not cross a page | ||
| 13 | * boundary when doing so. | ||
| 14 | * | ||
| 15 | * Much of the information about 21264 scheduling/coding comes from: | ||
| 16 | * Compiler Writer's Guide for the Alpha 21264 | ||
| 17 | * abbreviated as 'CWG' in other comments here | ||
| 18 | * ftp.digital.com/pub/Digital/info/semiconductor/literature/dsc-library.html | ||
| 19 | * Scheduling notation: | ||
| 20 | * E - either cluster | ||
| 21 | * U - upper subcluster; U0 - subcluster U0; U1 - subcluster U1 | ||
| 22 | * L - lower subcluster; L0 - subcluster L0; L1 - subcluster L1 | ||
| 23 | * Try not to change the actual algorithm if possible for consistency. | ||
| 24 | */ | ||
| 25 | |||
| 26 | #include <asm/regdef.h> | ||
| 27 | |||
| 28 | |||
| 29 | /* Allow an exception for an insn; exit if we get one. */ | ||
| 30 | #define EX(x,y...) \ | ||
| 31 | 99: x,##y; \ | ||
| 32 | .section __ex_table,"a"; \ | ||
| 33 | .long 99b - .; \ | ||
| 34 | lda v0, $exception-99b(zero); \ | ||
| 35 | .previous | ||
| 36 | |||
| 37 | |||
| 38 | .set noreorder | ||
| 39 | .set noat | ||
| 40 | .text | ||
| 41 | |||
| 42 | .globl __strlen_user | ||
| 43 | .ent __strlen_user | ||
| 44 | .frame sp, 0, ra | ||
| 45 | |||
| 46 | .align 4 | ||
| 47 | __strlen_user: | ||
| 48 | ldah a1, 32767(zero) # do not use plain strlen_user() for strings | ||
| 49 | # that might be almost 2 GB long; you should | ||
| 50 | # be using strnlen_user() instead | ||
| 51 | nop | ||
| 52 | nop | ||
| 53 | nop | ||
| 54 | |||
| 55 | .globl __strnlen_user | ||
| 56 | |||
| 57 | .align 4 | ||
| 58 | __strnlen_user: | ||
| 59 | .prologue 0 | ||
| 60 | EX( ldq_u t0, 0(a0) ) # L : load first quadword (a0 may be misaligned) | ||
| 61 | lda t1, -1(zero) # E : | ||
| 62 | |||
| 63 | insqh t1, a0, t1 # U : | ||
| 64 | andnot a0, 7, v0 # E : | ||
| 65 | or t1, t0, t0 # E : | ||
| 66 | subq a0, 1, a0 # E : get our +1 for the return | ||
| 67 | |||
| 68 | cmpbge zero, t0, t1 # E : t1 <- bitmask: bit i == 1 <==> i-th byte == 0 | ||
| 69 | subq a1, 7, t2 # E : | ||
| 70 | subq a0, v0, t0 # E : | ||
| 71 | bne t1, $found # U : | ||
| 72 | |||
| 73 | addq t2, t0, t2 # E : | ||
| 74 | addq a1, 1, a1 # E : | ||
| 75 | nop # E : | ||
| 76 | nop # E : | ||
| 77 | |||
| 78 | .align 4 | ||
| 79 | $loop: ble t2, $limit # U : | ||
| 80 | EX( ldq t0, 8(v0) ) # L : | ||
| 81 | nop # E : | ||
| 82 | nop # E : | ||
| 83 | |||
| 84 | cmpbge zero, t0, t1 # E : | ||
| 85 | subq t2, 8, t2 # E : | ||
| 86 | addq v0, 8, v0 # E : addr += 8 | ||
| 87 | beq t1, $loop # U : | ||
| 88 | |||
| 89 | $found: cttz t1, t2 # U0 : | ||
| 90 | addq v0, t2, v0 # E : | ||
| 91 | subq v0, a0, v0 # E : | ||
| 92 | ret # L0 : | ||
| 93 | |||
| 94 | $exception: | ||
| 95 | nop | ||
| 96 | nop | ||
| 97 | nop | ||
| 98 | ret | ||
| 99 | |||
| 100 | .align 4 # currently redundant | ||
| 101 | $limit: | ||
| 102 | nop | ||
| 103 | nop | ||
| 104 | subq a1, t2, v0 | ||
| 105 | ret | ||
| 106 | |||
| 107 | .end __strlen_user | ||