diff options
Diffstat (limited to 'libc/sysdeps/powerpc/powerpc64/power4/memcmp.S')
| -rw-r--r-- | libc/sysdeps/powerpc/powerpc64/power4/memcmp.S | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/libc/sysdeps/powerpc/powerpc64/power4/memcmp.S b/libc/sysdeps/powerpc/powerpc64/power4/memcmp.S index ce323f1e2..7df52f810 100644 --- a/libc/sysdeps/powerpc/powerpc64/power4/memcmp.S +++ b/libc/sysdeps/powerpc/powerpc64/power4/memcmp.S @@ -1,5 +1,5 @@ /* Optimized strcmp implementation for PowerPC64. - Copyright (C) 2003, 2006, 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 @@ -53,7 +53,7 @@ EALIGN (BP_SYM(memcmp), 4, 0) beq- cr6, L(zeroLength) dcbt 0,rSTR1 dcbt 0,rSTR2 -/* If less than 8 bytes or not aligned, use the unalligned +/* If less than 8 bytes or not aligned, use the unaligned byte loop. */ blt cr1, L(bytealigned) std rWORD8,-8(r1) @@ -62,7 +62,7 @@ EALIGN (BP_SYM(memcmp), 4, 0) cfi_offset(rWORD7,-16) bne L(unaligned) /* At this point we know both strings have the same alignment and the - compare length is at least 8 bytes. rBITDIF containes the low order + compare length is at least 8 bytes. rBITDIF contains the low order 3 bits of rSTR1 and cr5 contains the result of the logical compare of rBITDIF to 0. If rBITDIF == 0 then we are already double word aligned and can perform the DWaligned loop. @@ -70,7 +70,7 @@ EALIGN (BP_SYM(memcmp), 4, 0) Otherwise we know the two strings have the same alignment (but not yet DW). So we can force the string addresses to the next lower DW boundary and special case this first DW word using shift left to - ellimiate bits preceeding the first byte. Since we want to join the + eliminate bits preceding the first byte. Since we want to join the normal (DWaligned) compare loop, starting at the second double word, we need to adjust the length (rN) and special case the loop versioning for the first DW. This insures that the loop count is @@ -152,8 +152,8 @@ L(DWaligned): L(dP1): mtctr rTMP /* Power4 wants mtctr 1st in dispatch group */ /* Normally we'd use rWORD7/rWORD8 here, but since we might exit early - (8-15 byte compare), we want to use only volitile registers. This - means we can avoid restoring non-volitile registers since we did not + (8-15 byte compare), we want to use only volatile registers. This + means we can avoid restoring non-volatile registers since we did not change any on the early exit path. The key here is the non-early exit path only cares about the condition code (cr5), not about which register pair was used. */ @@ -215,7 +215,7 @@ L(dP2e): bne cr5, L(dLcr5) b L(dLoop2) /* Again we are on a early exit path (16-23 byte compare), we want to - only use volitile registers and avoid restoring non-volitile + only use volatile registers and avoid restoring non-volatile registers. */ .align 4 L(dP2x): @@ -256,7 +256,7 @@ L(dP3e): bne cr6, L(dLcr6) b L(dLoop1) /* Again we are on a early exit path (24-31 byte compare), we want to - only use volitile registers and avoid restoring non-volitile + only use volatile registers and avoid restoring non-volatile registers. */ .align 4 L(dP3x): @@ -340,7 +340,7 @@ L(d04): beq L(zeroLength) /* At this point we have a remainder of 1 to 7 bytes to compare. Since we are aligned it is safe to load the whole double word, and use - shift right double to elliminate bits beyond the compare length. */ + shift right double to eliminate bits beyond the compare length. */ L(d00): ld rWORD1, 8(rSTR1) ld rWORD2, 8(rSTR2) @@ -496,15 +496,15 @@ L(zeroLength): .align 4 /* At this point we know the strings have different alignment and the - compare length is at least 8 bytes. rBITDIF containes the low order + compare length is at least 8 bytes. rBITDIF contains the low order 3 bits of rSTR1 and cr5 contains the result of the logical compare of rBITDIF to 0. If rBITDIF == 0 then rStr1 is double word aligned and can perform the DWunaligned loop. - Otherwise we know that rSTR1 is not aready DW aligned yet. + Otherwise we know that rSTR1 is not already DW aligned yet. So we can force the string addresses to the next lower DW boundary and special case this first DW word using shift left to - ellimiate bits preceeding the first byte. Since we want to join the + eliminate bits preceding the first byte. Since we want to join the normal (DWaligned) compare loop, starting at the second double word, we need to adjust the length (rN) and special case the loop versioning for the first DW. This insures that the loop count is @@ -537,7 +537,7 @@ L(unaligned): clrrdi rSTR2, rSTR2, 3 std r26,-48(r1) cfi_offset(r26,-48) -/* Compute the leaft/right shift counts for the unalign rSTR2, +/* Compute the left/right shift counts for the unalign rSTR2, compensating for the logical (DW aligned) start of rSTR1. */ clrldi rSHL, r27, 61 clrrdi rSTR1, rSTR1, 3 @@ -876,7 +876,7 @@ L(du14): sldi. rN, rN, 3 bne cr5, L(duLcr5) /* At this point we have a remainder of 1 to 7 bytes to compare. We use - shift right double to elliminate bits beyond the compare length. + shift right double to eliminate bits beyond the compare length. This allows the use of double word subtract to compute the final result. |