# HG changeset patch # User Bram Moolenaar # Date 1574693104 -3600 # Node ID 128662297ddf1c186eed7e1be9e02a75a76ed9bc # Parent 975583db60c0ab85b185e406038203303424f35e patch 8.1.2342: random number generator in Vim script is slow Commit: https://github.com/vim/vim/commit/06b0b4bc27077013e9b4b48fd1d9b33e543ccf99 Author: Bram Moolenaar Date: Mon Nov 25 15:40:55 2019 +0100 patch 8.1.2342: random number generator in Vim script is slow Problem: Random number generator in Vim script is slow. Solution: Add rand() and srand(). (Yasuhiro Matsumoto, closes https://github.com/vim/vim/issues/1277) diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt --- a/runtime/doc/eval.txt +++ b/runtime/doc/eval.txt @@ -2648,6 +2648,7 @@ pumvisible() Number whether popup menu pyeval({expr}) any evaluate |Python| expression py3eval({expr}) any evaluate |python3| expression pyxeval({expr}) any evaluate |python_x| expression +rand([{expr}]) Number get pseudo-random number range({expr} [, {max} [, {stride}]]) List items from {expr} to {max} readdir({dir} [, {expr}]) List file names in {dir} selected by {expr} @@ -2761,6 +2762,7 @@ spellsuggest({word} [, {max} [, {capital split({expr} [, {pat} [, {keepempty}]]) List make |List| from {pat} separated {expr} sqrt({expr}) Float square root of {expr} +srand([{expr}]) List get seed for |rand()| state([{what}]) String current state of Vim str2float({expr}) Float convert String to Float str2list({expr} [, {utf8}]) List convert each character of {expr} to @@ -7637,6 +7639,20 @@ range({expr} [, {max} [, {stride}]]) Can also be used as a |method|: > GetExpr()->range() < + +rand([{expr}]) *rand()* + Return a pseudo-random Number generated with an xorshift + algorithm using seed {expr}. {expr} can be initialized by + |srand()| and will be updated by rand(). + If {expr} is omitted, an internal seed value is used and + updated. + + Examples: > + :echo rand() + :let seed = srand() + :echo rand(seed) + :echo rand(seed) +< *readdir()* readdir({directory} [, {expr}]) Return a list with file and directory names in {directory}. @@ -9130,6 +9146,19 @@ sqrt({expr}) *sqrt()* {only available when compiled with the |+float| feature} +srand([{expr}]) *srand()* + Initialize seed used by |rand()|: + - If {expr} is not given, seed values are initialized by + time(NULL) a.k.a. epoch time. + - If {expr} is given, return seed values which x element is + {expr}. This is useful for testing or when a predictable + sequence is expected. + + Examples: > + :let seed = srand() + :let seed = srand(userinput) + :echo rand(seed) + state([{what}]) *state()* Return a string which contains characters indicating the current state. Mostly useful in callbacks that want to do diff --git a/src/evalfunc.c b/src/evalfunc.c --- a/src/evalfunc.c +++ b/src/evalfunc.c @@ -169,6 +169,7 @@ static void f_pyeval(typval_T *argvars, #if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) static void f_pyxeval(typval_T *argvars, typval_T *rettv); #endif +static void f_rand(typval_T *argvars, typval_T *rettv); static void f_range(typval_T *argvars, typval_T *rettv); static void f_reg_executing(typval_T *argvars, typval_T *rettv); static void f_reg_recording(typval_T *argvars, typval_T *rettv); @@ -225,6 +226,7 @@ static void f_spellsuggest(typval_T *arg static void f_split(typval_T *argvars, typval_T *rettv); #ifdef FEAT_FLOAT static void f_sqrt(typval_T *argvars, typval_T *rettv); +static void f_srand(typval_T *argvars, typval_T *rettv); static void f_str2float(typval_T *argvars, typval_T *rettv); #endif static void f_str2list(typval_T *argvars, typval_T *rettv); @@ -634,6 +636,7 @@ static funcentry_T global_functions[] = #if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) {"pyxeval", 1, 1, FEARG_1, f_pyxeval}, #endif + {"rand", 0, 1, FEARG_1, f_rand}, {"range", 1, 3, FEARG_1, f_range}, {"readdir", 1, 2, FEARG_1, f_readdir}, {"readfile", 1, 3, FEARG_1, f_readfile}, @@ -725,6 +728,7 @@ static funcentry_T global_functions[] = {"split", 1, 3, FEARG_1, f_split}, #ifdef FEAT_FLOAT {"sqrt", 1, 1, FEARG_1, f_sqrt}, + {"srand", 0, 1, FEARG_1, f_srand}, #endif {"state", 0, 1, FEARG_1, f_state}, #ifdef FEAT_FLOAT @@ -5129,6 +5133,79 @@ f_pyxeval(typval_T *argvars, typval_T *r #endif /* + * "rand()" function + */ + static void +f_rand(typval_T *argvars, typval_T *rettv) +{ + list_T *l = NULL; + UINT32_T x, y, z, w, t; + static int rand_seed_initialized = FALSE; + static UINT32_T xyzw[4] = {123456789, 362436069, 521288629, 88675123}; + +#define SHUFFLE_XORSHIFT128 \ + t = x ^ (x << 11); \ + x = y; y = z; z = w; \ + w = (w ^ (w >> 19)) ^ (t ^ (t >> 8)); + + if (argvars[0].v_type == VAR_UNKNOWN) + { + // When argument is not given, return random number initialized + // statically. + if (!rand_seed_initialized) + { + xyzw[0] = (varnumber_T)time(NULL); + rand_seed_initialized = TRUE; + } + + x = xyzw[0]; + y = xyzw[1]; + z = xyzw[2]; + w = xyzw[3]; + SHUFFLE_XORSHIFT128; + xyzw[0] = x; + xyzw[1] = y; + xyzw[2] = z; + xyzw[3] = w; + } + else if (argvars[0].v_type == VAR_LIST) + { + listitem_T *lx, *ly, *lz, *lw; + + l = argvars[0].vval.v_list; + if (list_len(l) != 4) + goto theend; + + lx = list_find(l, 0L); + ly = list_find(l, 1L); + lz = list_find(l, 2L); + lw = list_find(l, 3L); + if (lx->li_tv.v_type != VAR_NUMBER) goto theend; + if (ly->li_tv.v_type != VAR_NUMBER) goto theend; + if (lz->li_tv.v_type != VAR_NUMBER) goto theend; + if (lw->li_tv.v_type != VAR_NUMBER) goto theend; + x = (UINT32_T)lx->li_tv.vval.v_number; + y = (UINT32_T)ly->li_tv.vval.v_number; + z = (UINT32_T)lz->li_tv.vval.v_number; + w = (UINT32_T)lw->li_tv.vval.v_number; + SHUFFLE_XORSHIFT128; + lx->li_tv.vval.v_number = (varnumber_T)x; + ly->li_tv.vval.v_number = (varnumber_T)y; + lz->li_tv.vval.v_number = (varnumber_T)z; + lw->li_tv.vval.v_number = (varnumber_T)w; + } + else + goto theend; + + rettv->v_type = VAR_NUMBER; + rettv->vval.v_number = (varnumber_T)w; + return; + +theend: + semsg(_(e_invarg2), tv_get_string(&argvars[0])); +} + +/* * "range()" function */ static void @@ -7013,6 +7090,31 @@ f_sqrt(typval_T *argvars, typval_T *rett } /* + * "srand()" function + */ + static void +f_srand(typval_T *argvars, typval_T *rettv) +{ + if (rettv_list_alloc(rettv) == FAIL) + return; + if (argvars[0].v_type == VAR_UNKNOWN) + list_append_number(rettv->vval.v_list, (varnumber_T)vim_time()); + else + { + int error = FALSE; + UINT32_T x = (UINT32_T)tv_get_number_chk(&argvars[0], &error); + + if (error) + return; + + list_append_number(rettv->vval.v_list, x); + } + list_append_number(rettv->vval.v_list, 362436069); + list_append_number(rettv->vval.v_list, 521288629); + list_append_number(rettv->vval.v_list, 88675123); +} + +/* * "str2float()" function */ static void diff --git a/src/testdir/Make_all.mak b/src/testdir/Make_all.mak --- a/src/testdir/Make_all.mak +++ b/src/testdir/Make_all.mak @@ -211,6 +211,7 @@ NEW_TESTS = \ test_pyx3 \ test_quickfix \ test_quotestar \ + test_random \ test_recover \ test_regex_char_classes \ test_regexp_latin \ @@ -403,6 +404,7 @@ NEW_TESTS_RES = \ test_pyx3.res \ test_quickfix.res \ test_quotestar.res \ + test_random.res \ test_regex_char_classes.res \ test_registers.res \ test_restricted.res \ diff --git a/src/testdir/test_random.vim b/src/testdir/test_random.vim new file mode 100644 --- /dev/null +++ b/src/testdir/test_random.vim @@ -0,0 +1,28 @@ +" Tests for srand() and rand() + +func Test_Rand() + let r = srand(123456789) + call assert_equal([123456789, 362436069, 521288629, 88675123], r) + call assert_equal(3701687786, rand(r)) + call assert_equal(458299110, rand(r)) + call assert_equal(2500872618, rand(r)) + call assert_equal(3633119408, rand(r)) + call assert_equal(516391518, rand(r)) + + call test_settime(12341234) + let s = srand() + call assert_equal(s, srand()) + call test_settime(12341235) + call assert_notequal(s, srand()) + + call srand() + let v = rand() + call assert_notequal(v, rand()) + + call assert_fails('echo srand([1])', 'E745:') + call assert_fails('echo rand([1, 2, 3])', 'E475:') + call assert_fails('echo rand([[1], 2, 3, 4])', 'E475:') + call assert_fails('echo rand([1, [2], 3, 4])', 'E475:') + call assert_fails('echo rand([1, 2, [3], 4])', 'E475:') + call assert_fails('echo rand([1, 2, 3, [4]])', 'E475:') +endfunc diff --git a/src/version.c b/src/version.c --- a/src/version.c +++ b/src/version.c @@ -738,6 +738,8 @@ static char *(features[]) = static int included_patches[] = { /* Add new patch number below this line */ /**/ + 2342, +/**/ 2341, /**/ 2340,