On Sat, 4 May 2024 19:35:21 GMT, Scott Gibbons <sgibb...@openjdk.org> wrote:
>> Re-write the IndexOf code without the use of the pcmpestri instruction, only >> using AVX2 instructions. This change accelerates String.IndexOf on average >> 1.3x for AVX2. The benchmark numbers: >> >> >> Benchmark Score >> Latest >> StringIndexOf.advancedWithMediumSub 343.573 317.934 >> 0.925375393x >> StringIndexOf.advancedWithShortSub1 1039.081 1053.96 >> 1.014319384x >> StringIndexOf.advancedWithShortSub2 55.828 110.541 >> 1.980027943x >> StringIndexOf.constantPattern 9.361 11.906 >> 1.271872663x >> StringIndexOf.searchCharLongSuccess 4.216 4.218 >> 1.000474383x >> StringIndexOf.searchCharMediumSuccess 3.133 3.216 >> 1.02649218x >> StringIndexOf.searchCharShortSuccess 3.76 3.761 >> 1.000265957x >> StringIndexOf.success 9.186 >> 9.713 1.057369911x >> StringIndexOf.successBig 14.341 46.343 >> 3.231504079x >> StringIndexOfChar.latin1_AVX2_String 6220.918 12154.52 >> 1.953814533x >> StringIndexOfChar.latin1_AVX2_char 5503.556 5540.044 >> 1.006629895x >> StringIndexOfChar.latin1_SSE4_String 6978.854 6818.689 >> 0.977049957x >> StringIndexOfChar.latin1_SSE4_char 5657.499 5474.624 >> 0.967675646x >> StringIndexOfChar.latin1_Short_String 7132.541 >> 6863.359 0.962260014x >> StringIndexOfChar.latin1_Short_char 16013.389 16162.437 >> 1.009307711x >> StringIndexOfChar.latin1_mixed_String 7386.123 14771.622 >> 1.999915517x >> StringIndexOfChar.latin1_mixed_char 9901.671 9782.245 >> 0.987938803 > > Scott Gibbons has updated the pull request incrementally with one additional > commit since the last revision: > > Rearrange; add lambdas for clarity src/hotspot/cpu/x86/stubGenerator_x86_64_string.cpp line 1476: > 1474: _masm); > 1475: > 1476: __ movq(r11, -1); There doesn't seem to be a use of r11 below in this function. src/hotspot/cpu/x86/stubGenerator_x86_64_string.cpp line 1493: > 1491: // Assume r10 is n - k > 1492: __ leaq(last, Address(haystack, r10, Address::times_1, isU ? -30 : > -31)); > 1493: __ jmpb(temp); Need to pass r10 as parameter. Also temp label could be given a better name. src/hotspot/cpu/x86/stubGenerator_x86_64_string.cpp line 1502: > 1500: > 1501: __ cmpq(hsPtrRet, last); > 1502: __ cmovq(Assembler::aboveEqual, hsPtrRet, last); cmovq is expensive, better sequence would be: __ cmpq(hsPtrRet, last); __ jb_b(temp); __ movq(hsPtrRet, last); src/hotspot/cpu/x86/stubGenerator_x86_64_string.cpp line 1510: > 1508: compare_big_haystack_to_needle(sizeKnown, size, > NUMBER_OF_NEEDLE_BYTES_TO_COMPARE, loop_top, hsPtrRet, hsLength, > 1509: needleLen, isU, DO_EARLY_BAILOUT, > eq_mask, temp2, r10, _masm); > 1510: At this point hsLength is not the remaining length from hsPtrRet, would that cause a problem? If not, all the special paths in compare_big_haystack_to_needle need not be generated on this call. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/16753#discussion_r1602016421 PR Review Comment: https://git.openjdk.org/jdk/pull/16753#discussion_r1601943761 PR Review Comment: https://git.openjdk.org/jdk/pull/16753#discussion_r1602251994 PR Review Comment: https://git.openjdk.org/jdk/pull/16753#discussion_r1602010926
