From 726f05dca7cf112651486f2272f933efbbe60888 Mon Sep 17 00:00:00 2001 From: otto Date: Wed, 29 Nov 2017 19:13:31 +0000 Subject: [PATCH] fold bsqrt_stop into bsqrt; from kshe; ok tom@ --- usr.bin/dc/bcode.c | 39 ++++++++++++--------------------------- 1 file changed, 12 insertions(+), 27 deletions(-) diff --git a/usr.bin/dc/bcode.c b/usr.bin/dc/bcode.c index 8e435bb8d9e..307c4aa7e60 100644 --- a/usr.bin/dc/bcode.c +++ b/usr.bin/dc/bcode.c @@ -1,4 +1,4 @@ -/* $OpenBSD: bcode.c,v 1.55 2017/11/28 17:43:45 otto Exp $ */ +/* $OpenBSD: bcode.c,v 1.56 2017/11/29 19:13:31 otto Exp $ */ /* * Copyright (c) 2003, Otto Moerbeek @@ -95,7 +95,6 @@ static void bdiv(void); static void bmod(void); static void bdivmod(void); static void bexp(void); -static bool bsqrt_stop(const BIGNUM *, const BIGNUM *, u_int *); static void bsqrt(void); static void not(void); static void equal_numbers(void); @@ -1268,28 +1267,12 @@ bexp(void) free_number(p); } -static bool -bsqrt_stop(const BIGNUM *x, const BIGNUM *y, u_int *onecount) -{ - BIGNUM *r; - bool ret; - - r = BN_new(); - bn_checkp(r); - bn_check(BN_sub(r, x, y)); - if (BN_is_one(r)) - (*onecount)++; - ret = BN_is_zero(r); - BN_free(r); - return ret || *onecount > 1; -} - static void bsqrt(void) { struct number *n; struct number *r; - BIGNUM *x, *y; + BIGNUM *x, *y, *t; u_int scale, onecount; BN_CTX *ctx; @@ -1312,14 +1295,16 @@ bsqrt(void) bn_checkp(y); ctx = BN_CTX_new(); bn_checkp(ctx); - for (;;) { - bn_checkp(BN_copy(y, x)); - bn_check(BN_div(x, NULL, n->number, x, ctx)); - bn_check(BN_add(x, x, y)); - bn_check(BN_rshift1(x, x)); - if (bsqrt_stop(x, y, &onecount)) - break; - } + do { + bn_check(BN_div(y, NULL, n->number, x, ctx)); + bn_check(BN_add(y, x, y)); + bn_check(BN_rshift1(y, y)); + bn_check(BN_sub(x, y, x)); + t = x; + x = y; + y = t; + } while (!BN_is_zero(y) && (onecount += BN_is_one(y)) < 2); + bn_check(BN_sub(y, x, y)); r = bmalloc(sizeof(*r)); r->scale = scale; r->number = y; -- 2.20.1