diff options
Diffstat (limited to 'libc/sysdeps/powerpc/powerpc32/power4/memcmp.S')
| -rw-r--r-- | libc/sysdeps/powerpc/powerpc32/power4/memcmp.S | 126 |
1 files changed, 63 insertions, 63 deletions
diff --git a/libc/sysdeps/powerpc/powerpc32/power4/memcmp.S b/libc/sysdeps/powerpc/powerpc32/power4/memcmp.S index edec7ab27..d7050a2f7 100644 --- a/libc/sysdeps/powerpc/powerpc32/power4/memcmp.S +++ b/libc/sysdeps/powerpc/powerpc32/power4/memcmp.S @@ -53,17 +53,17 @@ EALIGN (memcmp, 4, 0) blt cr1, L(bytealigned) stwu 1,-64(1) cfi_adjust_cfa_offset(64) - stw r31,48(1) + stw r31,48(1) cfi_offset(31,(48-64)) - stw r30,44(1) + stw r30,44(1) cfi_offset(30,(44-64)) bne L(unaligned) /* At this point we know both strings have the same alignment and the compare length is at least 8 bytes. rBITDIF contains the low order 2 bits of rSTR1 and cr5 contains the result of the logical compare - of rBITDIF to 0. If rBITDIF == 0 then we are already word + of rBITDIF to 0. If rBITDIF == 0 then we are already word aligned and can perform the word aligned loop. - + Otherwise we know the two strings have the same alignment (but not yet word aligned). So we force the string addresses to the next lower word boundary and special case this first word using shift left to @@ -143,7 +143,7 @@ L(Waligned): beq L(dP4) bgt cr1, L(dP3) beq cr1, L(dP2) - + /* Remainder is 4 */ .align 4 L(dP1): @@ -152,7 +152,7 @@ L(dP1): (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 + exit path only cares about the condition code (cr5), not about which register pair was used. */ lwz rWORD5, 0(rSTR1) lwz rWORD6, 0(rSTR2) @@ -170,7 +170,7 @@ L(dP1e): cmplw cr6, rWORD5, rWORD6 bne cr5, L(dLcr5) bne cr0, L(dLcr0) - + lwzu rWORD7, 16(rSTR1) lwzu rWORD8, 16(rSTR2) bne cr1, L(dLcr1) @@ -188,7 +188,7 @@ L(dP1x): bne L(d00) li rRTN, 0 blr - + /* Remainder is 8 */ .align 4 L(dP2): @@ -230,7 +230,7 @@ L(dP2x): bne L(d00) li rRTN, 0 blr - + /* Remainder is 12 */ .align 4 L(dP3): @@ -273,7 +273,7 @@ L(dP3x): bne L(d00) li rRTN, 0 blr - + /* Count is a multiple of 16, remainder is 0 */ .align 4 L(dP4): @@ -316,8 +316,8 @@ L(dLoop3): lwzu rWORD8, 16(rSTR2) bne- cr1, L(dLcr1) cmplw cr0, rWORD1, rWORD2 - bdnz+ L(dLoop) - + bdnz+ L(dLoop) + L(dL4): cmplw cr1, rWORD3, rWORD4 bne cr6, L(dLcr6) @@ -332,7 +332,7 @@ L(d24): bne cr6, L(dLcr6) L(d14): slwi. r12, rN, 3 - bne cr5, L(dLcr5) + bne cr5, L(dLcr5) L(d04): lwz r30,44(1) lwz r31,48(1) @@ -341,10 +341,10 @@ L(d04): beq L(zeroLength) /* At this point we have a remainder of 1 to 3 bytes to compare. Since we are aligned it is safe to load the whole word, and use - shift right to eliminate bits beyond the compare length. */ + shift right to eliminate bits beyond the compare length. */ L(d00): lwz rWORD1, 4(rSTR1) - lwz rWORD2, 4(rSTR2) + lwz rWORD2, 4(rSTR2) srw rWORD1, rWORD1, rN srw rWORD2, rWORD2, rN cmplw rWORD1,rWORD2 @@ -392,22 +392,22 @@ L(dLcr5x): bgtlr cr5 li rRTN, -1 blr - + .align 4 L(bytealigned): cfi_adjust_cfa_offset(-64) mtctr rN /* Power4 wants mtctr 1st in dispatch group */ /* We need to prime this loop. This loop is swing modulo scheduled - to avoid pipe delays. The dependent instruction latencies (load to + to avoid pipe delays. The dependent instruction latencies (load to compare to conditional branch) is 2 to 3 cycles. In this loop each dispatch group ends in a branch and takes 1 cycle. Effectively - the first iteration of the loop only serves to load operands and - branches based on compares are delayed until the next loop. + the first iteration of the loop only serves to load operands and + branches based on compares are delayed until the next loop. So we must precondition some registers and condition codes so that we don't exit the loop early on the first iteration. */ - + lbz rWORD1, 0(rSTR1) lbz rWORD2, 0(rSTR2) bdz- L(b11) @@ -427,7 +427,7 @@ L(bLoop): cmplw cr6, rWORD5, rWORD6 bdz- L(b3i) - + lbzu rWORD3, 1(rSTR1) lbzu rWORD4, 1(rSTR2) bne- cr1, L(bLcr1) @@ -441,10 +441,10 @@ L(bLoop): cmplw cr1, rWORD3, rWORD4 bdnz+ L(bLoop) - + /* We speculatively loading bytes before we have tested the previous bytes. But we must avoid overrunning the length (in the ctr) to - prevent these speculative loads from causing a segfault. In this + prevent these speculative loads from causing a segfault. In this case the loop will exit early (before the all pending bytes are tested. In this case we must complete the pending operations before returning. */ @@ -488,7 +488,7 @@ L(bx56): nop L(b12): bne- cr0, L(bx12) -L(bx34): +L(bx34): sub rRTN, rWORD3, rWORD4 blr @@ -497,7 +497,7 @@ L(bx12): sub rRTN, rWORD1, rWORD2 blr - .align 4 + .align 4 L(zeroLengthReturn): L(zeroLength): @@ -509,9 +509,9 @@ L(zeroLength): /* At this point we know the strings have different alignment and the compare length is at least 8 bytes. rBITDIF contains the low order 2 bits of rSTR1 and cr5 contains the result of the logical compare - of rBITDIF to 0. If rBITDIF == 0 then rStr1 is word aligned and can + of rBITDIF to 0. If rBITDIF == 0 then rStr1 is word aligned and can perform the Wunaligned loop. - + Otherwise we know that rSTR1 is not aready word aligned yet. So we can force the string addresses to the next lower word boundary and special case this first word using shift left to @@ -531,13 +531,13 @@ L(zeroLength): #define rE r0 /* Right rotation temp for rWORD6. */ #define rG r12 /* Right rotation temp for rWORD8. */ L(unaligned): - stw r29,40(r1) - cfi_offset(r29,(40-64)) + stw r29,40(r1) + cfi_offset(r29,(40-64)) clrlwi rSHL, rSTR2, 30 - stw r28,36(r1) + stw r28,36(r1) cfi_offset(r28,(36-64)) beq cr5, L(Wunaligned) - stw r27,32(r1) + stw r27,32(r1) cfi_offset(r27,(32-64)) /* Adjust the logical start of rSTR2 to compensate for the extra bits in the 1st rSTR1 W. */ @@ -545,19 +545,19 @@ L(unaligned): /* But do not attempt to address the W before that W that contains the actual start of rSTR2. */ clrrwi rSTR2, rSTR2, 2 - stw r26,28(r1) + stw r26,28(r1) cfi_offset(r26,(28-64)) /* Compute the left/right shift counts for the unalign rSTR2, - compensating for the logical (W aligned) start of rSTR1. */ + compensating for the logical (W aligned) start of rSTR1. */ clrlwi rSHL, r27, 30 - clrrwi rSTR1, rSTR1, 2 - stw r25,24(r1) + clrrwi rSTR1, rSTR1, 2 + stw r25,24(r1) cfi_offset(r25,(24-64)) slwi rSHL, rSHL, 3 cmplw cr5, r27, rSTR2 add rN, rN, rBITDIF slwi r11, rBITDIF, 3 - stw r24,20(r1) + stw r24,20(r1) cfi_offset(r24,(20-64)) subfic rSHR, rSHL, 32 srwi rTMP, rN, 4 /* Divide by 16 */ @@ -633,16 +633,16 @@ L(duPs4): compare length is at least 8 bytes. */ .align 4 L(Wunaligned): - stw r27,32(r1) + stw r27,32(r1) cfi_offset(r27,(32-64)) clrrwi rSTR2, rSTR2, 2 - stw r26,28(r1) + stw r26,28(r1) cfi_offset(r26,(28-64)) srwi rTMP, rN, 4 /* Divide by 16 */ - stw r25,24(r1) + stw r25,24(r1) cfi_offset(r25,(24-64)) andi. rBITDIF, rN, 12 /* Get the W remainder */ - stw r24,20(r1) + stw r24,20(r1) cfi_offset(r24,(20-64)) slwi rSHL, rSHL, 3 lwz rWORD6, 0(rSTR2) @@ -656,7 +656,7 @@ L(Wunaligned): mtctr rTMP /* Power4 wants mtctr 1st in dispatch group */ bgt cr1, L(duP3) beq cr1, L(duP2) - + /* Remainder is 4 */ .align 4 L(duP1): @@ -687,7 +687,7 @@ L(duP1e): bne cr0, L(duLcr0) or rWORD6, rE, rF cmplw cr6, rWORD5, rWORD6 - b L(duLoop3) + b L(duLoop3) .align 4 /* At this point we exit early with the first word compare complete and remainder of 0 to 3 bytes. See L(du14) for details on @@ -751,7 +751,7 @@ L(duP2x): lwz rWORD2, 4(rSTR2) srw rA, rWORD2, rSHR b L(dutrim) - + /* Remainder is 12 */ .align 4 L(duP3): @@ -801,7 +801,7 @@ L(duP3x): lwz rWORD2, 4(rSTR2) srw rA, rWORD2, rSHR b L(dutrim) - + /* Count is a multiple of 16, remainder is 0 */ .align 4 L(duP4): @@ -867,8 +867,8 @@ L(duLoop3): srw rG, rWORD8, rSHR slw rB, rWORD8, rSHL or rWORD8, rG, rH - bdnz+ L(duLoop) - + bdnz+ L(duLoop) + L(duL4): bne cr1, L(duLcr1) cmplw cr1, rWORD3, rWORD4 @@ -886,9 +886,9 @@ L(du14): slwi. rN, rN, 3 bne cr5, L(duLcr5) /* At this point we have a remainder of 1 to 3 bytes to compare. We use - shift right to eliminate bits beyond the compare length. + shift right to eliminate bits beyond the compare length. - However it may not be safe to load rWORD2 which may be beyond the + However it may not be safe to load rWORD2 which may be beyond the string length. So we compare the bit length of the remainder to the right shift count (rSHR). If the bit count is less than or equal we do not need to load rWORD2 (all significant bits are already in @@ -903,13 +903,13 @@ L(du14): L(dutrim): lwz rWORD1, 4(rSTR1) lwz r31,48(1) - subfic rN, rN, 32 /* Shift count is 32 - (rN * 8). */ + subfic rN, rN, 32 /* Shift count is 32 - (rN * 8). */ or rWORD2, rA, rB lwz r30,44(1) lwz r29,40(r1) srw rWORD1, rWORD1, rN srw rWORD2, rWORD2, rN - lwz r28,36(r1) + lwz r28,36(r1) lwz r27,32(r1) cmplw rWORD1,rWORD2 li rRTN,0 @@ -923,9 +923,9 @@ L(duLcr0): lwz r31,48(1) lwz r30,44(1) li rRTN, 1 - bgt cr0, L(dureturn29) + bgt cr0, L(dureturn29) lwz r29,40(r1) - lwz r28,36(r1) + lwz r28,36(r1) li rRTN, -1 b L(dureturn27) .align 4 @@ -933,9 +933,9 @@ L(duLcr1): lwz r31,48(1) lwz r30,44(1) li rRTN, 1 - bgt cr1, L(dureturn29) + bgt cr1, L(dureturn29) lwz r29,40(r1) - lwz r28,36(r1) + lwz r28,36(r1) li rRTN, -1 b L(dureturn27) .align 4 @@ -943,9 +943,9 @@ L(duLcr6): lwz r31,48(1) lwz r30,44(1) li rRTN, 1 - bgt cr6, L(dureturn29) + bgt cr6, L(dureturn29) lwz r29,40(r1) - lwz r28,36(r1) + lwz r28,36(r1) li rRTN, -1 b L(dureturn27) .align 4 @@ -953,9 +953,9 @@ L(duLcr5): lwz r31,48(1) lwz r30,44(1) li rRTN, 1 - bgt cr5, L(dureturn29) + bgt cr5, L(dureturn29) lwz r29,40(r1) - lwz r28,36(r1) + lwz r28,36(r1) li rRTN, -1 b L(dureturn27) .align 3 @@ -965,14 +965,14 @@ L(duZeroReturn): L(dureturn): lwz r31,48(1) lwz r30,44(1) -L(dureturn29): +L(dureturn29): lwz r29,40(r1) - lwz r28,36(r1) -L(dureturn27): + lwz r28,36(r1) +L(dureturn27): lwz r27,32(r1) -L(dureturn26): +L(dureturn26): lwz r26,28(r1) -L(dureturn25): +L(dureturn25): lwz r25,24(r1) lwz r24,20(r1) lwz 1,0(1) |