From a8e391f3baf2cfbcfa57e46d4cfe95c089921100 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Thu, 7 Sep 2017 17:51:43 +0200 Subject: Rewrite select_val_bins so that its labels can be packed --- erts/emulator/beam/beam_load.c | 52 ++++++++++-------------------------------- 1 file changed, 12 insertions(+), 40 deletions(-) (limited to 'erts/emulator/beam/beam_load.c') diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c index 9bb5866cb3..944ff7bc4c 100644 --- a/erts/emulator/beam/beam_load.c +++ b/erts/emulator/beam/beam_load.c @@ -4039,7 +4039,6 @@ gen_select_val(LoaderState* stp, GenOpArg S, GenOpArg Fail, int i, j, align = 0; if (size == 2) { - /* * Use a special-cased instruction if there are only two values. */ @@ -4056,47 +4055,19 @@ gen_select_val(LoaderState* stp, GenOpArg S, GenOpArg Fail, op->a[5] = Rest[3]; return op; - - } else if (size > 10) { - - /* binary search instruction */ - - NEW_GENOP(stp, op); - op->next = NULL; - op->op = genop_i_select_val_bins_3; - GENOP_ARITY(op, arity); - op->a[0] = S; - op->a[1] = Fail; - op->a[2].type = TAG_u; - op->a[2].val = size; - for (i = 3; i < arity; i++) { - op->a[i] = Rest[i-3]; - } - - /* - * Sort the values to make them useful for a binary search. - */ - - qsort(op->a+3, size, 2*sizeof(GenOpArg), - (int (*)(const void *, const void *)) genopargcompare); -#ifdef DEBUG - for (i = 3; i < arity-2; i += 2) { - ASSERT(op->a[i].val < op->a[i+2].val); - } -#endif - return op; } - /* linear search instruction */ - - align = 1; + if (size <= 10) { + /* Use linear search. Reserve place for a sentinel. */ + align = 1; + } arity += 2*align; size += align; NEW_GENOP(stp, op); op->next = NULL; - op->op = genop_i_select_val_lins_3; + op->op = (align == 0) ? genop_i_select_val_bins_3 : genop_i_select_val_lins_3; GENOP_ARITY(op, arity); op->a[0] = S; op->a[1] = Fail; @@ -4110,7 +4081,7 @@ gen_select_val(LoaderState* stp, GenOpArg S, GenOpArg Fail, } /* - * Sort the values to make them useful for a sentinel search + * Sort the values to make them useful for a binary or sentinel search. */ qsort(tmp, size - align, 2*sizeof(GenOpArg), @@ -4125,11 +4096,12 @@ gen_select_val(LoaderState* stp, GenOpArg S, GenOpArg Fail, erts_free(ERTS_ALC_T_LOADER_TMP, (void *) tmp); - /* add sentinel */ - - op->a[j].type = TAG_u; - op->a[j].val = ~((BeamInstr)0); - op->a[j+size] = Fail; + if (align) { + /* Add sentinel for linear search. */ + op->a[j].type = TAG_u; + op->a[j].val = ~((BeamInstr)0); + op->a[j+size] = Fail; + } #ifdef DEBUG for (i = 0; i < size - 1; i++) { -- cgit v1.2.3