mercurial/mpatch.c
author Pierre-Yves David <pierre-yves.david@octobus.net>
Sat, 25 Apr 2020 12:37:46 +0200
changeset 46151 c6bc77f7e593
parent 41336 763b45bc4483
child 46819 d4ba4d51f85f
permissions -rw-r--r--
copies-rust: tokenize all paths into integer Copy information for each changesets tend to affect a small new number of path. However, each of these path might be handled a large number of time. Handling HgPathBuf (aka `Vec<u8>`) is expensive. Handling integer is cheap. With this patch we: - turn any input path into an integer "token" early, - do all the internal logic using such "token", - turn "token" back into path right before returning a result. This gives use a quite significant performance boost in our slower cases. Repo Case Source-Rev Dest-Rev # of revisions old time new time Difference Factor time per rev --------------------------------------------------------------------------------------------------------------------------------------------------------------- pypy x000_revs_x000_added_x_copies 8a3b5bfd266e 2c68e87c3efe : 6780 revs, 0.092828 s, 0.081225 s, -0.011603 s, × 0.8750, 11 µs/rev pypy x0000_revs_x_added_0_copies d1defd0dc478 c9cb1334cc78 : 43645 revs, 0.711975 s, 0.586011 s, -0.125964 s, × 0.8231, 13 µs/rev pypy x0000_revs_xx000_added_x000_copies 08ea3258278e d9fa043f30c0 : 11316 revs, 0.124505 s, 0.114173 s, -0.010332 s, × 0.9170, 10 µs/rev netbeans x000_revs_x000_added_x000_copies ff453e9fee32 411350406ec2 : 5750 revs, 0.072072 s, 0.061004 s, -0.011068 s, × 0.8464, 10 µs/rev netbeans x0000_revs_xx000_added_x000_copies 588c2d1ced70 1aad62e59ddd : 66949 revs, 0.682732 s, 0.535874 s, -0.146858 s, × 0.7849, 8 µs/rev mozilla-central x00000_revs_x0000_added_x0000_copies 6832ae71433c 4c222a1d9a00 : 153721 revs, 1.935918 s, 1.781383 s, -0.154535 s, × 0.9202, 11 µs/rev mozilla-central x00000_revs_x00000_added_x000_copies 76caed42cf7c 1daa622bbe42 : 204976 revs, 2.827320 s, 2.603867 s, -0.223453 s, × 0.9210, 12 µs/rev mozilla-try x0000_revs_xx000_added_x000_copies 89294cd501d9 7ccb2fc7ccb5 : 97052 revs, 3.243010 s, 1.529120 s, -1.713890 s, × 0.4715, 15 µs/rev mozilla-try x00000_revs_x_added_0_copies 6a320851d377 1ebb79acd503 : 363753 revs, 5.693818 s, 4.842699 s, -0.851119 s, × 0.8505, 13 µs/rev mozilla-try x00000_revs_x_added_x_copies 5173c4b6f97c 95d83ee7242d : 362229 revs, 5.677655 s, 4.761732 s, -0.915923 s, × 0.8387, 13 µs/rev mozilla-try x00000_revs_x000_added_x_copies 9126823d0e9c ca82787bb23c : 359344 revs, 5.563370 s, 4.733912 s, -0.829458 s, × 0.8509, 13 µs/rev mozilla-try x00000_revs_x0000_added_x0000_copies 8d3fafa80d4b eb884023b810 : 192665 revs, 2.864099 s, 2.593410 s, -0.270689 s, × 0.9055, 13 µs/rev mozilla-try x00000_revs_x00000_added_x0000_copies 1b661134e2ca 1ae03d022d6d : 228985 revs, 113.297287 s, 41.041198 s, -72.256089 s, × 0.3622, 179 µs/rev mozilla-try x00000_revs_x00000_added_x000_copies 9b2a99adc05e 8e29777b48e6 : 382065 revs, 59.498652 s, 27.915689 s, -31.582963 s, × 0.4692, 73 µs/rev Full timing comparison between this revision and the previous one: Repo Case Source-Rev Dest-Rev # of revisions old time new time Difference Factor time per rev --------------------------------------------------------------------------------------------------------------------------------------------------------------- mercurial x_revs_x_added_0_copies ad6b123de1c7 39cfcef4f463 : 1 revs, 0.000042 s, 0.000042 s, +0.000000 s, × 1.0000, 42 µs/rev mercurial x_revs_x_added_x_copies 2b1c78674230 0c1d10351869 : 6 revs, 0.000104 s, 0.000110 s, +0.000006 s, × 1.0577, 18 µs/rev mercurial x000_revs_x000_added_x_copies 81f8ff2a9bf2 dd3267698d84 : 1032 revs, 0.004913 s, 0.004918 s, +0.000005 s, × 1.0010, 4 µs/rev pypy x_revs_x_added_0_copies aed021ee8ae8 099ed31b181b : 9 revs, 0.000191 s, 0.000195 s, +0.000004 s, × 1.0209, 21 µs/rev pypy x_revs_x000_added_0_copies 4aa4e1f8e19a 359343b9ac0e : 1 revs, 0.000050 s, 0.000049 s, -0.000001 s, × 0.9800, 49 µs/rev pypy x_revs_x_added_x_copies ac52eb7bbbb0 72e022663155 : 7 revs, 0.000112 s, 0.000112 s, +0.000000 s, × 1.0000, 16 µs/rev pypy x_revs_x00_added_x_copies c3b14617fbd7 ace7255d9a26 : 1 revs, 0.000288 s, 0.000324 s, +0.000036 s, × 1.1250, 324 µs/rev pypy x_revs_x000_added_x000_copies df6f7a526b60 a83dc6a2d56f : 6 revs, 0.010411 s, 0.010611 s, +0.000200 s, × 1.0192, 1768 µs/rev pypy x000_revs_xx00_added_0_copies 89a76aede314 2f22446ff07e : 4785 revs, 0.052852 s, 0.050835 s, -0.002017 s, × 0.9618, 10 µs/rev pypy x000_revs_x000_added_x_copies 8a3b5bfd266e 2c68e87c3efe : 6780 revs, 0.092828 s, 0.081225 s, -0.011603 s, × 0.8750, 11 µs/rev pypy x000_revs_x000_added_x000_copies 89a76aede314 7b3dda341c84 : 5441 revs, 0.063269 s, 0.061291 s, -0.001978 s, × 0.9687, 11 µs/rev pypy x0000_revs_x_added_0_copies d1defd0dc478 c9cb1334cc78 : 43645 revs, 0.711975 s, 0.586011 s, -0.125964 s, × 0.8231, 13 µs/rev pypy x0000_revs_xx000_added_0_copies bf2c629d0071 4ffed77c095c : 2 revs, 0.012771 s, 0.012824 s, +0.000053 s, × 1.0042, 6412 µs/rev pypy x0000_revs_xx000_added_x000_copies 08ea3258278e d9fa043f30c0 : 11316 revs, 0.124505 s, 0.114173 s, -0.010332 s, × 0.9170, 10 µs/rev netbeans x_revs_x_added_0_copies fb0955ffcbcd a01e9239f9e7 : 2 revs, 0.000082 s, 0.000085 s, +0.000003 s, × 1.0366, 42 µs/rev netbeans x_revs_x000_added_0_copies 6f360122949f 20eb231cc7d0 : 2 revs, 0.000111 s, 0.000108 s, -0.000003 s, × 0.9730, 54 µs/rev netbeans x_revs_x_added_x_copies 1ada3faf6fb6 5a39d12eecf4 : 3 revs, 0.000171 s, 0.000175 s, +0.000004 s, × 1.0234, 58 µs/rev netbeans x_revs_x00_added_x_copies 35be93ba1e2c 9eec5e90c05f : 9 revs, 0.000708 s, 0.000719 s, +0.000011 s, × 1.0155, 79 µs/rev netbeans x000_revs_xx00_added_0_copies eac3045b4fdd 51d4ae7f1290 : 1421 revs, 0.010608 s, 0.010175 s, -0.000433 s, × 0.9592, 7 µs/rev netbeans x000_revs_x000_added_x_copies e2063d266acd 6081d72689dc : 1533 revs, 0.015635 s, 0.015569 s, -0.000066 s, × 0.9958, 10 µs/rev netbeans x000_revs_x000_added_x000_copies ff453e9fee32 411350406ec2 : 5750 revs, 0.072072 s, 0.061004 s, -0.011068 s, × 0.8464, 10 µs/rev netbeans x0000_revs_xx000_added_x000_copies 588c2d1ced70 1aad62e59ddd : 66949 revs, 0.682732 s, 0.535874 s, -0.146858 s, × 0.7849, 8 µs/rev mozilla-central x_revs_x_added_0_copies 3697f962bb7b 7015fcdd43a2 : 2 revs, 0.000090 s, 0.000090 s, +0.000000 s, × 1.0000, 45 µs/rev mozilla-central x_revs_x000_added_0_copies dd390860c6c9 40d0c5bed75d : 8 revs, 0.000210 s, 0.000281 s, +0.000071 s, × 1.3381, 35 µs/rev mozilla-central x_revs_x_added_x_copies 8d198483ae3b 14207ffc2b2f : 9 revs, 0.000182 s, 0.000187 s, +0.000005 s, × 1.0275, 20 µs/rev mozilla-central x_revs_x00_added_x_copies 98cbc58cc6bc 446a150332c3 : 7 revs, 0.000594 s, 0.000660 s, +0.000066 s, × 1.1111, 94 µs/rev mozilla-central x_revs_x000_added_x000_copies 3c684b4b8f68 0a5e72d1b479 : 3 revs, 0.003102 s, 0.003385 s, +0.000283 s, × 1.0912, 1128 µs/rev mozilla-central x_revs_x0000_added_x0000_copies effb563bb7e5 c07a39dc4e80 : 6 revs, 0.060234 s, 0.069812 s, +0.009578 s, × 1.1590, 11635 µs/rev mozilla-central x000_revs_xx00_added_0_copies 6100d773079a 04a55431795e : 1593 revs, 0.006300 s, 0.006503 s, +0.000203 s, × 1.0322, 4 µs/rev mozilla-central x000_revs_x000_added_x_copies 9f17a6fc04f9 2d37b966abed : 41 revs, 0.004817 s, 0.004988 s, +0.000171 s, × 1.0355, 121 µs/rev mozilla-central x000_revs_x000_added_x000_copies 7c97034feb78 4407bd0c6330 : 7839 revs, 0.065451 s, 0.063963 s, -0.001488 s, × 0.9773, 8 µs/rev mozilla-central x0000_revs_xx000_added_0_copies 9eec5917337d 67118cc6dcad : 615 revs, 0.026282 s, 0.026225 s, -0.000057 s, × 0.9978, 42 µs/rev mozilla-central x0000_revs_xx000_added_x000_copies f78c615a656c 96a38b690156 : 30263 revs, 0.206873 s, 0.201377 s, -0.005496 s, × 0.9734, 6 µs/rev mozilla-central x00000_revs_x0000_added_x0000_copies 6832ae71433c 4c222a1d9a00 : 153721 revs, 1.935918 s, 1.781383 s, -0.154535 s, × 0.9202, 11 µs/rev mozilla-central x00000_revs_x00000_added_x000_copies 76caed42cf7c 1daa622bbe42 : 204976 revs, 2.827320 s, 2.603867 s, -0.223453 s, × 0.9210, 12 µs/rev mozilla-try x_revs_x_added_0_copies aaf6dde0deb8 9790f499805a : 2 revs, 0.000842 s, 0.000845 s, +0.000003 s, × 1.0036, 422 µs/rev mozilla-try x_revs_x000_added_0_copies d8d0222927b4 5bb8ce8c7450 : 2 revs, 0.000870 s, 0.000862 s, -0.000008 s, × 0.9908, 431 µs/rev mozilla-try x_revs_x_added_x_copies 092fcca11bdb 936255a0384a : 4 revs, 0.000165 s, 0.000161 s, -0.000004 s, × 0.9758, 40 µs/rev mozilla-try x_revs_x00_added_x_copies b53d2fadbdb5 017afae788ec : 2 revs, 0.001145 s, 0.001163 s, +0.000018 s, × 1.0157, 581 µs/rev mozilla-try x_revs_x000_added_x000_copies 20408ad61ce5 6f0ee96e21ad : 1 revs, 0.026500 s, 0.032414 s, +0.005914 s, × 1.2232, 32414 µs/rev mozilla-try x_revs_x0000_added_x0000_copies effb563bb7e5 c07a39dc4e80 : 6 revs, 0.059407 s, 0.070149 s, +0.010742 s, × 1.1808, 11691 µs/rev mozilla-try x000_revs_xx00_added_0_copies 6100d773079a 04a55431795e : 1593 revs, 0.006325 s, 0.006526 s, +0.000201 s, × 1.0318, 4 µs/rev mozilla-try x000_revs_x000_added_x_copies 9f17a6fc04f9 2d37b966abed : 41 revs, 0.005171 s, 0.005187 s, +0.000016 s, × 1.0031, 126 µs/rev mozilla-try x000_revs_x000_added_x000_copies 1346fd0130e4 4c65cbdabc1f : 6657 revs, 0.066837 s, 0.065047 s, -0.001790 s, × 0.9732, 9 µs/rev mozilla-try x0000_revs_x_added_0_copies 63519bfd42ee a36a2a865d92 : 40314 revs, 0.314252 s, 0.301129 s, -0.013123 s, × 0.9582, 7 µs/rev mozilla-try x0000_revs_x_added_x_copies 9fe69ff0762d bcabf2a78927 : 38690 revs, 0.304160 s, 0.280683 s, -0.023477 s, × 0.9228, 7 µs/rev mozilla-try x0000_revs_xx000_added_x_copies 156f6e2674f2 4d0f2c178e66 : 8598 revs, 0.089223 s, 0.084897 s, -0.004326 s, × 0.9515, 9 µs/rev mozilla-try x0000_revs_xx000_added_0_copies 9eec5917337d 67118cc6dcad : 615 revs, 0.026711 s, 0.026620 s, -0.000091 s, × 0.9966, 43 µs/rev mozilla-try x0000_revs_xx000_added_x000_copies 89294cd501d9 7ccb2fc7ccb5 : 97052 revs, 3.243010 s, 1.529120 s, -1.713890 s, × 0.4715, 15 µs/rev mozilla-try x0000_revs_x0000_added_x0000_copies e928c65095ed e951f4ad123a : 52031 revs, 0.756500 s, 0.738709 s, -0.017791 s, × 0.9765, 14 µs/rev mozilla-try x00000_revs_x_added_0_copies 6a320851d377 1ebb79acd503 : 363753 revs, 5.693818 s, 4.842699 s, -0.851119 s, × 0.8505, 13 µs/rev mozilla-try x00000_revs_x00000_added_0_copies dc8a3ca7010e d16fde900c9c : 34414 revs, 0.590904 s, 0.596946 s, +0.006042 s, × 1.0102, 17 µs/rev mozilla-try x00000_revs_x_added_x_copies 5173c4b6f97c 95d83ee7242d : 362229 revs, 5.677655 s, 4.761732 s, -0.915923 s, × 0.8387, 13 µs/rev mozilla-try x00000_revs_x000_added_x_copies 9126823d0e9c ca82787bb23c : 359344 revs, 5.563370 s, 4.733912 s, -0.829458 s, × 0.8509, 13 µs/rev mozilla-try x00000_revs_x0000_added_x0000_copies 8d3fafa80d4b eb884023b810 : 192665 revs, 2.864099 s, 2.593410 s, -0.270689 s, × 0.9055, 13 µs/rev mozilla-try x00000_revs_x00000_added_x0000_copies 1b661134e2ca 1ae03d022d6d : 228985 revs, 113.297287 s, 41.041198 s, -72.256089 s, × 0.3622, 179 µs/rev mozilla-try x00000_revs_x00000_added_x000_copies 9b2a99adc05e 8e29777b48e6 : 382065 revs, 59.498652 s, 27.915689 s, -31.582963 s, × 0.4692, 73 µs/rev Full timing comparison between this revision and the filelog copy tracing. Repo Case Source-Rev Dest-Rev # of revisions filelog sidedata Difference Factor time per rev --------------------------------------------------------------------------------------------------------------------------------------------------------------- mercurial x_revs_x_added_0_copies ad6b123de1c7 39cfcef4f463 : 1 revs, 0.000903 s, 0.000042 s, -0.000861 s, × 0.0465, 41 µs/rev mercurial x_revs_x_added_x_copies 2b1c78674230 0c1d10351869 : 6 revs, 0.001861 s, 0.000110 s, -0.001751 s, × 0.0591, 18 µs/rev mercurial x000_revs_x000_added_x_copies 81f8ff2a9bf2 dd3267698d84 : 1032 revs, 0.018577 s, 0.004918 s, -0.013659 s, × 0.2647, 4 µs/rev pypy x_revs_x_added_0_copies aed021ee8ae8 099ed31b181b : 9 revs, 0.001519 s, 0.000195 s, -0.001324 s, × 0.1283, 21 µs/rev pypy x_revs_x000_added_0_copies 4aa4e1f8e19a 359343b9ac0e : 1 revs, 0.213855 s, 0.000049 s, -0.350d73 s, × 0.0002, 48 µs/rev pypy x_revs_x_added_x_copies ac52eb7bbbb0 72e022663155 : 7 revs, 0.017022 s, 0.000112 s, -0.016910 s, × 0.0065, 15 µs/rev pypy x_revs_x00_added_x_copies c3b14617fbd7 ace7255d9a26 : 1 revs, 0.019398 s, 0.000324 s, -0.019074 s, × 0.0167, 323 µs/rev pypy x_revs_x000_added_x000_copies df6f7a526b60 a83dc6a2d56f : 6 revs, 0.769467 s, 0.010611 s, -0.758856 s, × 0.0137, 1768 µs/rev pypy x000_revs_xx00_added_0_copies 89a76aede314 2f22446ff07e : 4785 revs, 1.221952 s, 0.050835 s, -1.171117 s, × 0.0416, 10 µs/rev pypy x000_revs_x000_added_x_copies 8a3b5bfd266e 2c68e87c3efe : 6780 revs, 1.304007 s, 0.081225 s, -1.222782 s, × 0.0622, 11 µs/rev pypy x000_revs_x000_added_x000_copies 89a76aede314 7b3dda341c84 : 5441 revs, 1.686610 s, 0.061291 s, -1.625319 s, × 0.0363, 11 µs/rev pypy x0000_revs_x_added_0_copies d1defd0dc478 c9cb1334cc78 : 43645 revs, 0.001107 s, 0.586011 s, +0.584904 s, × 529.36, 13 µs/rev pypy x0000_revs_xx000_added_0_copies bf2c629d0071 4ffed77c095c : 2 revs, 1.100760 s, 0.012824 s, -1.087936 s, × 0.0116, 6408 µs/rev pypy x0000_revs_xx000_added_x000_copies 08ea3258278e d9fa043f30c0 : 11316 revs, 1.350547 s, 0.114173 s, -1.236374 s, × 0.0845, 10 µs/rev netbeans x_revs_x_added_0_copies fb0955ffcbcd a01e9239f9e7 : 2 revs, 0.027864 s, 0.000085 s, -0.027779 s, × 0.0030, 42 µs/rev netbeans x_revs_x000_added_0_copies 6f360122949f 20eb231cc7d0 : 2 revs, 0.132479 s, 0.000108 s, -0.132371 s, × 0.0008, 53 µs/rev netbeans x_revs_x_added_x_copies 1ada3faf6fb6 5a39d12eecf4 : 3 revs, 0.025405 s, 0.000175 s, -0.025230 s, × 0.0068, 58 µs/rev netbeans x_revs_x00_added_x_copies 35be93ba1e2c 9eec5e90c05f : 9 revs, 0.053244 s, 0.000719 s, -0.052525 s, × 0.0135, 79 µs/rev netbeans x000_revs_xx00_added_0_copies eac3045b4fdd 51d4ae7f1290 : 1421 revs, 0.038017 s, 0.010175 s, -0.027842 s, × 0.2676, 7 µs/rev netbeans x000_revs_x000_added_x_copies e2063d266acd 6081d72689dc : 1533 revs, 0.198308 s, 0.015569 s, -0.182739 s, × 0.0785, 10 µs/rev netbeans x000_revs_x000_added_x000_copies ff453e9fee32 411350406ec2 : 5750 revs, 0.949749 s, 0.061004 s, -0.888745 s, × 0.0642, 10 µs/rev netbeans x0000_revs_xx000_added_x000_copies 588c2d1ced70 1aad62e59ddd : 66949 revs, 3.932262 s, 0.535874 s, -3.396388 s, × 0.1362, 8 µs/rev mozilla-central x_revs_x_added_0_copies 3697f962bb7b 7015fcdd43a2 : 2 revs, 0.024490 s, 0.000090 s, -0.024400 s, × 0.0036, 44 µs/rev mozilla-central x_revs_x000_added_0_copies dd390860c6c9 40d0c5bed75d : 8 revs, 0.143885 s, 0.000281 s, -0.143604 s, × 0.0019, 35 µs/rev mozilla-central x_revs_x_added_x_copies 8d198483ae3b 14207ffc2b2f : 9 revs, 0.025471 s, 0.000187 s, -0.025284 s, × 0.0073, 20 µs/rev mozilla-central x_revs_x00_added_x_copies 98cbc58cc6bc 446a150332c3 : 7 revs, 0.086013 s, 0.000660 s, -0.085353 s, × 0.0076, 94 µs/rev mozilla-central x_revs_x000_added_x000_copies 3c684b4b8f68 0a5e72d1b479 : 3 revs, 0.200726 s, 0.003385 s, -0.197341 s, × 0.0168, 1127 µs/rev mozilla-central x_revs_x0000_added_x0000_copies effb563bb7e5 c07a39dc4e80 : 6 revs, 2.224171 s, 0.069812 s, -2.154359 s, × 0.0313, 11633 µs/rev mozilla-central x000_revs_xx00_added_0_copies 6100d773079a 04a55431795e : 1593 revs, 0.090780 s, 0.006503 s, -0.084277 s, × 0.0716, 4 µs/rev mozilla-central x000_revs_x000_added_x_copies 9f17a6fc04f9 2d37b966abed : 41 revs, 0.764805 s, 0.004988 s, -0.759817 s, × 0.0065, 121 µs/rev mozilla-central x000_revs_x000_added_x000_copies 7c97034feb78 4407bd0c6330 : 7839 revs, 1.161405 s, 0.063963 s, -1.097442 s, × 0.0550, 8 µs/rev mozilla-central x0000_revs_xx000_added_0_copies 9eec5917337d 67118cc6dcad : 615 revs, 6.816186 s, 0.026225 s, -6.789961 s, × 0.0038, 42 µs/rev mozilla-central x0000_revs_xx000_added_x000_copies f78c615a656c 96a38b690156 : 30263 revs, 3.374819 s, 0.201377 s, -3.173442 s, × 0.0596, 6 µs/rev mozilla-central x00000_revs_x0000_added_x0000_copies 6832ae71433c 4c222a1d9a00 : 153721 revs, 16.285469 s, 1.781383 s, -14.504086 s, × 0.1093, 11 µs/rev mozilla-central x00000_revs_x00000_added_x000_copies 76caed42cf7c 1daa622bbe42 : 204976 revs, 21.207733 s, 2.603867 s, -18.603866 s, × 0.1227, 12 µs/rev mozilla-try x_revs_x_added_0_copies aaf6dde0deb8 9790f499805a : 2 revs, 0.080843 s, 0.000845 s, -0.079998 s, × 0.0104, 422 µs/rev mozilla-try x_revs_x000_added_0_copies d8d0222927b4 5bb8ce8c7450 : 2 revs, 0.511068 s, 0.000862 s, -0.510206 s, × 0.0016, 430 µs/rev mozilla-try x_revs_x_added_x_copies 092fcca11bdb 936255a0384a : 4 revs, 0.021573 s, 0.000161 s, -0.021412 s, × 0.0074, 40 µs/rev mozilla-try x_revs_x00_added_x_copies b53d2fadbdb5 017afae788ec : 2 revs, 0.227726 s, 0.001163 s, -0.226563 s, × 0.0051, 581 µs/rev mozilla-try x_revs_x000_added_x000_copies 20408ad61ce5 6f0ee96e21ad : 1 revs, 1.120448 s, 0.032414 s, -1.088034 s, × 0.0289, 32381 µs/rev mozilla-try x_revs_x0000_added_x0000_copies effb563bb7e5 c07a39dc4e80 : 6 revs, 2.241713 s, 0.070149 s, -2.171564 s, × 0.0312, 11689 µs/rev mozilla-try x000_revs_xx00_added_0_copies 6100d773079a 04a55431795e : 1593 revs, 0.090633 s, 0.006526 s, -0.084107 s, × 0.0720, 4 µs/rev mozilla-try x000_revs_x000_added_x_copies 9f17a6fc04f9 2d37b966abed : 41 revs, 0.770403 s, 0.005187 s, -0.765216 s, × 0.0067, 126 µs/rev mozilla-try x000_revs_x000_added_x000_copies 1346fd0130e4 4c65cbdabc1f : 6657 revs, 1.184557 s, 0.065047 s, -1.119510 s, × 0.0549, 9 µs/rev mozilla-try x0000_revs_x_added_0_copies 63519bfd42ee a36a2a865d92 : 40314 revs, 0.085790 s, 0.301129 s, +0.215339 s, × 3.5100, 7 µs/rev mozilla-try x0000_revs_x_added_x_copies 9fe69ff0762d bcabf2a78927 : 38690 revs, 0.080616 s, 0.280683 s, +0.200067 s, × 3.4817, 7 µs/rev mozilla-try x0000_revs_xx000_added_x_copies 156f6e2674f2 4d0f2c178e66 : 8598 revs, 7.712554 s, 0.084897 s, -7.627657 s, × 0.0110, 9 µs/rev mozilla-try x0000_revs_xx000_added_0_copies 9eec5917337d 67118cc6dcad : 615 revs, 6.937294 s, 0.026620 s, -6.910674 s, × 0.0038, 43 µs/rev mozilla-try x0000_revs_xx000_added_x000_copies 89294cd501d9 7ccb2fc7ccb5 : 97052 revs, 7.712313 s, 1.529120 s, -6.183193 s, × 0.1982, 15 µs/rev mozilla-try x0000_revs_x0000_added_x0000_copies e928c65095ed e951f4ad123a : 52031 revs, 9.966910 s, 0.738709 s, -9.228201 s, × 0.0741, 14 µs/rev mozilla-try x00000_revs_x_added_0_copies 6a320851d377 1ebb79acd503 : 363753 revs, 0.090397 s, 4.842699 s, +4.752302 s, × 53.571, 13 µs/rev mozilla-try x00000_revs_x00000_added_0_copies dc8a3ca7010e d16fde900c9c : 34414 revs, 27.817167 s, 0.596946 s, -27.220221 s, × 0.0214, 17 µs/rev mozilla-try x00000_revs_x_added_x_copies 5173c4b6f97c 95d83ee7242d : 362229 revs, 0.091305 s, 4.761732 s, +4.670427 s, × 52.151, 13 µs/rev mozilla-try x00000_revs_x000_added_x_copies 9126823d0e9c ca82787bb23c : 359344 revs, 0.231183 s, 4.733912 s, +4.502729 s, × 20.476, 13 µs/rev mozilla-try x00000_revs_x0000_added_x0000_copies 8d3fafa80d4b eb884023b810 : 192665 revs, 19.830617 s, 2.593410 s, -17.237207 s, × 0.1307, 13 µs/rev mozilla-try x00000_revs_x00000_added_x0000_copies 1b661134e2ca 1ae03d022d6d : 228985 revs, 21.743873 s, 41.041198 s, +19.297325 s, × 1.8874, 179 µs/rev mozilla-try x00000_revs_x00000_added_x000_copies 9b2a99adc05e 8e29777b48e6 : 382065 revs, 25.935037 s, 27.915689 s, +1.980652 s, × 1.0763, 73 µs/rev Differential Revision: https://phab.mercurial-scm.org/D9493

/*
 mpatch.c - efficient binary patching for Mercurial

 This implements a patch algorithm that's O(m + nlog n) where m is the
 size of the output and n is the number of patches.

 Given a list of binary patches, it unpacks each into a hunk list,
 then combines the hunk lists with a treewise recursion to form a
 single hunk list. This hunk list is then applied to the original
 text.

 The text (or binary) fragments are copied directly from their source
 Python objects into a preallocated output string to avoid the
 allocation of intermediate Python objects. Working memory is about 2x
 the total number of hunks.

 Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>

 This software may be used and distributed according to the terms
 of the GNU General Public License, incorporated herein by reference.
*/

#include <limits.h>
#include <stdlib.h>
#include <string.h>

#include "bitmanipulation.h"
#include "compat.h"
#include "mpatch.h"

/* VC9 doesn't include bool and lacks stdbool.h based on cext/util.h */
#if defined(_MSC_VER) || __STDC_VERSION__ < 199901L
#define true 1
#define false 0
typedef unsigned char bool;
#else
#include <stdbool.h>
#endif

static struct mpatch_flist *lalloc(ssize_t size)
{
	struct mpatch_flist *a = NULL;

	if (size < 1) {
		size = 1;
	}

	a = (struct mpatch_flist *)malloc(sizeof(struct mpatch_flist));
	if (a) {
		a->base = (struct mpatch_frag *)malloc(
		    sizeof(struct mpatch_frag) * size);
		if (a->base) {
			a->head = a->tail = a->base;
			return a;
		}
		free(a);
	}
	return NULL;
}

void mpatch_lfree(struct mpatch_flist *a)
{
	if (a) {
		free(a->base);
		free(a);
	}
}

static ssize_t lsize(struct mpatch_flist *a)
{
	return a->tail - a->head;
}

/* add helper to add src and *dest iff it won't overflow */
static inline bool safeadd(int src, int *dest)
{
	if ((src > 0) == (*dest > 0)) {
		if (*dest > 0) {
			if (src > (INT_MAX - *dest)) {
				return false;
			}
		} else {
			if (src < (INT_MIN - *dest)) {
				return false;
			}
		}
	}
	*dest += src;
	return true;
}

/* subtract src from dest and store result in dest */
static inline bool safesub(int src, int *dest)
{
	if (((src > 0) && (*dest < INT_MIN + src)) ||
	    ((src < 0) && (*dest > INT_MAX + src))) {
		return false;
	}
	*dest -= src;
	return true;
}

/* move hunks in source that are less cut to dest, compensating
   for changes in offset. the last hunk may be split if necessary.
*/
static int gather(struct mpatch_flist *dest, struct mpatch_flist *src, int cut,
                  int offset)
{
	struct mpatch_frag *d = dest->tail, *s = src->head;
	int postend, c, l;

	while (s != src->tail) {
		int soffset = s->start;
		if (!safeadd(offset, &soffset)) {
			break; /* add would overflow, oh well */
		}
		if (soffset >= cut) {
			break; /* we've gone far enough */
		}

		postend = offset;
		if (!safeadd(s->start, &postend) ||
		    !safeadd(s->len, &postend)) {
			break;
		}
		if (postend <= cut) {
			/* save this hunk */
			int tmp = s->start;
			if (!safesub(s->end, &tmp)) {
				break;
			}
			if (!safeadd(s->len, &tmp)) {
				break;
			}
			if (!safeadd(tmp, &offset)) {
				break; /* add would overflow, oh well */
			}
			*d++ = *s++;
		} else {
			/* break up this hunk */
			c = cut;
			if (!safesub(offset, &c)) {
				break;
			}
			if (s->end < c) {
				c = s->end;
			}
			l = cut - offset - s->start;
			if (s->len < l) {
				l = s->len;
			}

			offset += s->start + l - c;

			d->start = s->start;
			d->end = c;
			d->len = l;
			d->data = s->data;
			d++;
			s->start = c;
			s->len = s->len - l;
			s->data = s->data + l;

			break;
		}
	}

	dest->tail = d;
	src->head = s;
	return offset;
}

/* like gather, but with no output list */
static int discard(struct mpatch_flist *src, int cut, int offset)
{
	struct mpatch_frag *s = src->head;
	int postend, c, l;

	while (s != src->tail) {
		int cmpcut = s->start;
		if (!safeadd(offset, &cmpcut)) {
			break;
		}
		if (cmpcut >= cut) {
			break;
		}

		postend = offset;
		if (!safeadd(s->start, &postend)) {
			break;
		}
		if (!safeadd(s->len, &postend)) {
			break;
		}
		if (postend <= cut) {
			/* do the subtraction first to avoid UB integer overflow
			 */
			int tmp = s->start;
			if (!safesub(s->end, &tmp)) {
				break;
			}
			if (!safeadd(s->len, &tmp)) {
				break;
			}
			if (!safeadd(tmp, &offset)) {
				break;
			}
			s++;
		} else {
			c = cut;
			if (!safesub(offset, &c)) {
				break;
			}
			if (s->end < c) {
				c = s->end;
			}
			l = cut - offset - s->start;
			if (s->len < l) {
				l = s->len;
			}

			offset += s->start + l - c;
			s->start = c;
			s->len = s->len - l;
			s->data = s->data + l;

			break;
		}
	}

	src->head = s;
	return offset;
}

/* combine hunk lists a and b, while adjusting b for offset changes in a/
   this deletes a and b and returns the resultant list. */
static struct mpatch_flist *combine(struct mpatch_flist *a,
                                    struct mpatch_flist *b)
{
	struct mpatch_flist *c = NULL;
	struct mpatch_frag *bh, *ct;
	int offset = 0, post;

	if (a && b) {
		c = lalloc((lsize(a) + lsize(b)) * 2);
	}

	if (c) {

		for (bh = b->head; bh != b->tail; bh++) {
			/* save old hunks */
			offset = gather(c, a, bh->start, offset);

			/* discard replaced hunks */
			post = discard(a, bh->end, offset);

			/* insert new hunk */
			ct = c->tail;
			ct->start = bh->start;
			ct->end = bh->end;
			if (!safesub(offset, &(ct->start)) ||
			    !safesub(post, &(ct->end))) {
				/* It was already possible to exit
				 * this function with a return value
				 * of NULL before the safesub()s were
				 * added, so this should be fine. */
				mpatch_lfree(c);
				c = NULL;
				goto done;
			}
			ct->len = bh->len;
			ct->data = bh->data;
			c->tail++;
			offset = post;
		}

		/* hold on to tail from a */
		memcpy(c->tail, a->head, sizeof(struct mpatch_frag) * lsize(a));
		c->tail += lsize(a);
	}
done:
	mpatch_lfree(a);
	mpatch_lfree(b);
	return c;
}

/* decode a binary patch into a hunk list */
int mpatch_decode(const char *bin, ssize_t len, struct mpatch_flist **res)
{
	struct mpatch_flist *l;
	struct mpatch_frag *lt;
	int pos = 0;

	/* assume worst case size, we won't have many of these lists */
	l = lalloc(len / 12 + 1);
	if (!l) {
		return MPATCH_ERR_NO_MEM;
	}

	lt = l->tail;

	/* We check against len-11 to ensure we have at least 12 bytes
	   left in the patch so we can read our three be32s out of it. */
	while (pos >= 0 && pos < (len - 11)) {
		lt->start = getbe32(bin + pos);
		lt->end = getbe32(bin + pos + 4);
		lt->len = getbe32(bin + pos + 8);
		if (lt->start < 0 || lt->start > lt->end || lt->len < 0) {
			break; /* sanity check */
		}
		if (!safeadd(12, &pos)) {
			break;
		}
		lt->data = bin + pos;
		if (!safeadd(lt->len, &pos)) {
			break;
		}
		lt++;
	}

	if (pos != len) {
		mpatch_lfree(l);
		return MPATCH_ERR_CANNOT_BE_DECODED;
	}

	l->tail = lt;
	*res = l;
	return 0;
}

/* calculate the size of resultant text */
ssize_t mpatch_calcsize(ssize_t len, struct mpatch_flist *l)
{
	ssize_t outlen = 0, last = 0;
	struct mpatch_frag *f = l->head;

	while (f != l->tail) {
		if (f->start < last || f->end > len) {
			return MPATCH_ERR_INVALID_PATCH;
		}
		outlen += f->start - last;
		last = f->end;
		outlen += f->len;
		f++;
	}

	outlen += len - last;
	return outlen;
}

int mpatch_apply(char *buf, const char *orig, ssize_t len,
                 struct mpatch_flist *l)
{
	struct mpatch_frag *f = l->head;
	int last = 0;
	char *p = buf;

	while (f != l->tail) {
		if (f->start < last || f->start > len || f->end > len ||
		    last < 0) {
			return MPATCH_ERR_INVALID_PATCH;
		}
		memcpy(p, orig + last, f->start - last);
		p += f->start - last;
		memcpy(p, f->data, f->len);
		last = f->end;
		p += f->len;
		f++;
	}
	if (last < 0) {
		return MPATCH_ERR_INVALID_PATCH;
	}
	memcpy(p, orig + last, len - last);
	return 0;
}

/* recursively generate a patch of all bins between start and end */
struct mpatch_flist *
mpatch_fold(void *bins, struct mpatch_flist *(*get_next_item)(void *, ssize_t),
            ssize_t start, ssize_t end)
{
	ssize_t len;

	if (start + 1 == end) {
		/* trivial case, output a decoded list */
		return get_next_item(bins, start);
	}

	/* divide and conquer, memory management is elsewhere */
	len = (end - start) / 2;
	return combine(mpatch_fold(bins, get_next_item, start, start + len),
	               mpatch_fold(bins, get_next_item, start + len, end));
}