diff options
Diffstat (limited to 'libc/sysdeps/powerpc/powerpc64/power6/memcpy.S')
| -rw-r--r-- | libc/sysdeps/powerpc/powerpc64/power6/memcpy.S | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/libc/sysdeps/powerpc/powerpc64/power6/memcpy.S b/libc/sysdeps/powerpc/powerpc64/power6/memcpy.S index 5487f95c4..64f5b2f42 100644 --- a/libc/sysdeps/powerpc/powerpc64/power6/memcpy.S +++ b/libc/sysdeps/powerpc/powerpc64/power6/memcpy.S @@ -1,5 +1,5 @@ /* Optimized memcpy implementation for PowerPC64. - Copyright (C) 2003, 2006, 2007, 2011 Free Software Foundation, Inc. + Copyright (C) 2003-2013 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -28,16 +28,16 @@ with the appropriate combination of byte and halfword load/stores. There is minimal effort to optimize the alignment of short moves. The 64-bit implementations of POWER3 and POWER4 do a reasonable job - of handling unligned load/stores that do not cross 32-byte boundries. + of handling unaligned load/stores that do not cross 32-byte boundaries. Longer moves (>= 32-bytes) justify the effort to get at least the destination doubleword (8-byte) aligned. Further optimization is - posible when both source and destination are doubleword aligned. + possible when both source and destination are doubleword aligned. Each case has a optimized unrolled loop. - For POWER6 unaligned loads will take a 20+ cycle hicup for any + For POWER6 unaligned loads will take a 20+ cycle hiccup for any L1 cache miss that crosses a 32- or 128-byte boundary. Store - is more forgiving and does not take a hicup until page or + is more forgiving and does not take a hiccup until page or segment boundaries. So we require doubleword alignment for the source but may take a risk and only require word alignment for the destination. */ @@ -50,9 +50,9 @@ EALIGN (BP_SYM (memcpy), 7, 0) neg 0,3 std 3,-16(1) std 31,-8(1) - andi. 11,3,7 /* check alignement of dst. */ + andi. 11,3,7 /* check alignment of dst. */ clrldi 0,0,61 /* Number of bytes until the 1st doubleword of dst. */ - clrldi 10,4,61 /* check alignement of src. */ + clrldi 10,4,61 /* check alignment of src. */ cmpldi cr6,5,8 ble- cr1,.L2 /* If move < 32 bytes use short move code. */ mtcrf 0x01,0 @@ -61,8 +61,8 @@ EALIGN (BP_SYM (memcpy), 7, 0) beq .L0 subf 5,0,5 - /* Move 0-7 bytes as needed to get the destination doubleword alligned. - Duplicate some code to maximize fall-throught and minimize agen delays. */ + /* Move 0-7 bytes as needed to get the destination doubleword aligned. + Duplicate some code to maximize fall-through and minimize agen delays. */ 1: bf 31,2f lbz 6,0(4) stb 6,0(3) @@ -95,10 +95,10 @@ EALIGN (BP_SYM (memcpy), 7, 0) add 4,4,0 add 3,3,0 - clrldi 10,4,61 /* check alignement of src again. */ + clrldi 10,4,61 /* check alignment of src again. */ srdi 9,5,3 /* Number of full double words remaining. */ - /* Copy doublewords from source to destination, assumpting the + /* Copy doublewords from source to destination, assuming the destination is aligned on a doubleword boundary. At this point we know there are at least 25 bytes left (32-7) to copy. @@ -130,7 +130,7 @@ EALIGN (BP_SYM (memcpy), 7, 0) load, load, store, store every 2 cycles. The following code is sensitive to cache line alignment. Do not - make any change with out first making sure thay don't result in + make any change with out first making sure they don't result in splitting ld/std pairs across a cache line. */ mtcrf 0x02,5 @@ -329,7 +329,7 @@ L(das_tail): L(das_tail2): /* At this point we have a tail of 0-7 bytes and we know that the - destiniation is double word aligned. */ + destination is double word aligned. */ 4: bf 29,2f lwz 6,0(4) stw 6,0(3) @@ -537,7 +537,7 @@ L(dus_tailX): .LE8: mr 12,4 bne cr6,L(dus_4) -/* Exactly 8 bytes. We may cross a 32-/128-byte boundry and take a ~20 +/* Exactly 8 bytes. We may cross a 32-/128-byte boundary and take a ~20 cycle delay. This case should be rare and any attempt to avoid this would take most of 20 cycles any way. */ ld 6,0(4) @@ -1146,7 +1146,7 @@ L(du_done): add 3,3,0 add 12,12,0 /* At this point we have a tail of 0-7 bytes and we know that the - destiniation is double word aligned. */ + destination is double word aligned. */ 4: bf 29,2f lwz 6,0(12) addi 12,12,4 |