diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc64/le/power10/strcmp.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc64/le/power10/strcmp.S | 161 |
1 files changed, 95 insertions, 66 deletions
diff --git a/sysdeps/powerpc/powerpc64/le/power10/strcmp.S b/sysdeps/powerpc/powerpc64/le/power10/strcmp.S index a3c1adad53..3406f4f26a 100644 --- a/sysdeps/powerpc/powerpc64/le/power10/strcmp.S +++ b/sysdeps/powerpc/powerpc64/le/power10/strcmp.S @@ -62,7 +62,7 @@ lxvl 32+v5,reg2,r0; \ add reg1,reg1,len_reg; \ add reg2,reg2,len_reg; \ - vcmpnezb. v7,v4,v5; \ + vcmpnezb v7,v4,v5; \ vctzlsbb r6,v7; \ cmpld cr7,r6,len_reg; \ blt cr7,L(different); \ @@ -72,70 +72,110 @@ .machine power9 ENTRY_TOCLESS (STRCMP, 4) - li r11,16 - /* eq bit of cr1 used as swap status flag to indicate if - source pointers were swapped. */ - crclr 4*cr1+eq - vspltisb v19,-1 - andi. r7,r3,15 - sub r7,r11,r7 /* r7(nalign1) = 16 - (str1 & 15). */ - andi. r9,r4,15 - sub r5,r11,r9 /* r5(nalign2) = 16 - (str2 & 15). */ - cmpld cr7,r7,r5 - beq cr7,L(same_aligned) - blt cr7,L(nalign1_min) - /* Swap r3 and r4, and r7 and r5 such that r3 and r7 hold the - pointer which is closer to the next 16B boundary so that only - one CHECK_N_BYTES is needed before entering the loop below. */ - mr r8,r4 - mr r4,r3 - mr r3,r8 - mr r12,r7 - mr r7,r5 - mr r5,r12 - crset 4*cr1+eq /* Set bit on swapping source pointers. */ + andi. r7,r3,4095 + andi. r8,r4,4095 + cmpldi cr0,r7,4096-16 + cmpldi cr1,r8,4096-16 + bgt cr0,L(crosses) + bgt cr1,L(crosses) + COMPARE_16(v4,v5,0) - .p2align 5 +L(crosses): + andi. r7,r3,15 + subfic r7,r7,16 /* r7(nalign1) = 16 - (str1 & 15). */ + andi. r9,r4,15 + subfic r5,r9,16 /* r5(nalign2) = 16 - (str2 & 15). */ + cmpld cr7,r7,r5 + beq cr7,L(same_aligned) + blt cr7,L(nalign1_min) + + /* nalign2 is minimum and s2 pointer is aligned. */ + CHECK_N_BYTES(r3,r4,r5) + /* Are we on the 64B hunk which crosses a page? */ + andi. r10,r3,63 /* Determine offset into 64B hunk. */ + andi. r8,r3,15 /* The offset into the 16B hunk. */ + neg r7,r3 + andi. r9,r7,15 /* Number of bytes after a 16B cross. */ + rlwinm. r7,r7,26,0x3F /* ((r3-4096))>>6&63. */ + beq L(compare_64_pagecross) + mtctr r7 + b L(compare_64B_unaligned) + + /* nalign1 is minimum and s1 pointer is aligned. */ L(nalign1_min): CHECK_N_BYTES(r3,r4,r7) + /* Are we on the 64B hunk which crosses a page? */ + andi. r10,r4,63 /* Determine offset into 64B hunk. */ + andi. r8,r4,15 /* The offset into the 16B hunk. */ + neg r7,r4 + andi. r9,r7,15 /* Number of bytes after a 16B cross. */ + rlwinm. r7,r7,26,0x3F /* ((r4-4096))>>6&63. */ + beq L(compare_64_pagecross) + mtctr r7 .p2align 5 -L(s1_aligned): - /* r9 and r5 is number of bytes to be read after and before - page boundary correspondingly. */ - sub r5,r5,r7 - subfic r9,r5,16 - /* Now let r7 hold the count of quadwords which can be - checked without crossing a page boundary. quadword offset is - (str2>>4)&0xFF. */ - rlwinm r7,r4,28,0xFF - /* Below check is required only for first iteration. For second - iteration and beyond, the new loop counter is always 255. */ - cmpldi r7,255 - beq L(L3) - /* Get the initial loop count by 255-((str2>>4)&0xFF). */ - subfic r11,r7,255 +L(compare_64B_unaligned): + COMPARE_16(v4,v5,0) + COMPARE_16(v4,v5,16) + COMPARE_16(v4,v5,32) + COMPARE_16(v4,v5,48) + addi r3,r3,64 + addi r4,r4,64 + bdnz L(compare_64B_unaligned) - .p2align 5 -L(L1): + /* Cross the page boundary of s2, carefully. Only for first + iteration we have to get the count of 64B blocks to be checked. + From second iteration and beyond, loop counter is always 63. */ +L(compare_64_pagecross): + li r11, 63 mtctr r11 - - .p2align 5 -L(L2): - COMPARE_16(v4,v5,0) /* Load 16B blocks using lxv. */ + cmpldi r10,16 + ble L(cross_4) + cmpldi r10,32 + ble L(cross_3) + cmpldi r10,48 + ble L(cross_2) +L(cross_1): + CHECK_N_BYTES(r3,r4,r9) + CHECK_N_BYTES(r3,r4,r8) + COMPARE_16(v4,v5,0) + COMPARE_16(v4,v5,16) + COMPARE_16(v4,v5,32) + addi r3,r3,48 + addi r4,r4,48 + b L(compare_64B_unaligned) +L(cross_2): + COMPARE_16(v4,v5,0) addi r3,r3,16 addi r4,r4,16 - bdnz L(L2) - /* Cross the page boundary of s2, carefully. */ - - .p2align 5 -L(L3): - CHECK_N_BYTES(r3,r4,r5) CHECK_N_BYTES(r3,r4,r9) - li r11,255 /* Load the new loop counter. */ - b L(L1) + CHECK_N_BYTES(r3,r4,r8) + COMPARE_16(v4,v5,0) + COMPARE_16(v4,v5,16) + addi r3,r3,32 + addi r4,r4,32 + b L(compare_64B_unaligned) +L(cross_3): + COMPARE_16(v4,v5,0) + COMPARE_16(v4,v5,16) + addi r3,r3,32 + addi r4,r4,32 + CHECK_N_BYTES(r3,r4,r9) + CHECK_N_BYTES(r3,r4,r8) + COMPARE_16(v4,v5,0) + addi r3,r3,16 + addi r4,r4,16 + b L(compare_64B_unaligned) +L(cross_4): + COMPARE_16(v4,v5,0) + COMPARE_16(v4,v5,16) + COMPARE_16(v4,v5,32) + addi r3,r3,48 + addi r4,r4,48 + CHECK_N_BYTES(r3,r4,r9) + CHECK_N_BYTES(r3,r4,r8) + b L(compare_64B_unaligned) - .p2align 5 L(same_aligned): CHECK_N_BYTES(r3,r4,r7) /* Align s1 to 32B and adjust s2 address. @@ -168,18 +208,7 @@ L(16B_aligned_loop): /* Calculate and return the difference. */ L(different): - vctzlsbb r6,v7 - vextubrx r5,r6,v4 - vextubrx r4,r6,v5 - bt 4*cr1+eq,L(swapped) - subf r3,r4,r5 - blr - - /* If src pointers were swapped, then swap the - indices and calculate the return value. */ -L(swapped): - subf r3,r5,r4 - blr + TAIL(v4,v5) .p2align 5 L(32B_aligned_loop): |