From c100247b248caf44b901abfe645ad793ecb41a51 Mon Sep 17 00:00:00 2001
From: "(no author)" <(no author)>
Date: Thu, 11 Feb 2010 20:36:56 +0000
Subject: [PATCH] Added a test for inv_divappr_q_n and made it pass.

---
 mpn/generic/inv_divappr_q_n.c | 13 +++++++------
 mpn/generic/tdiv_q.c          |  2 +-
 tests/mpn/Makefile.am         |  2 +-
 tests/mpn/Makefile.in         | 24 ++++++++++++++++--------
 4 files changed, 25 insertions(+), 16 deletions(-)

diff --git a/mpn/generic/inv_divappr_q_n.c b/mpn/generic/inv_divappr_q_n.c
index d93dccea..cfb4fdcd 100644
--- a/mpn/generic/inv_divappr_q_n.c
+++ b/mpn/generic/inv_divappr_q_n.c
@@ -21,6 +21,7 @@ MA 02110-1301, USA. */
 
 #include <mpir.h>
 #include "gmp-impl.h"
+#include "longlong.h"
 
 /* 
    Computes an approximate quotient of { np, 2*dn } by { dp, dn } which is
@@ -31,7 +32,7 @@ mp_limb_t
 mpn_inv_divappr_q_n(mp_ptr qp, mp_ptr np, 
                               mp_srcptr dp, mp_size_t dn, mp_srcptr inv)
 {
-   mp_limb_t ret = 0;
+   mp_limb_t cy, lo, ret = 0;
    mp_ptr tp;
    TMP_DECL;
 
@@ -43,9 +44,11 @@ mpn_inv_divappr_q_n(mp_ptr qp, mp_ptr np,
       mpn_sub_n(np + dn, np + dn, dp, dn);
    }
 
-   tp = TMP_ALLOC_LIMBS(2*dn);
-   mpn_mulhigh_n(tp, np + dn, inv, dn);
-   mpn_add_n(qp, tp + dn, dp, dn);
+   tp = TMP_ALLOC_LIMBS(2*dn + 1);
+   mpn_mul(tp, np + dn - 1, dn + 1, inv, dn);
+   add_ssaaaa(cy, lo, 0, np[dn - 1], 0, tp[dn]);
+   mpn_add_n(qp, tp + dn + 1, np + dn, dn);
+   ret += mpn_add_1(qp, qp, dn, cy + 1);
 
    /* 
       Let X = B^dn + inv, D = { dp, dn }, N = { np, 2*dn }, then
@@ -55,8 +58,6 @@ mpn_inv_divappr_q_n(mp_ptr qp, mp_ptr np,
       NX//B^{2*dn} <= N//D <= NX//B^{2*dn} + 1.
    */
       
-   ret += mpn_add_1(qp, qp, dn, 1);
-   
    if (UNLIKELY(ret == 2))
    {
       ret = 1;
diff --git a/mpn/generic/tdiv_q.c b/mpn/generic/tdiv_q.c
index c968a571..61ddb761 100644
--- a/mpn/generic/tdiv_q.c
+++ b/mpn/generic/tdiv_q.c
@@ -196,7 +196,7 @@ mpn_tdiv_q (mp_ptr qp,
 	    {
            mp_ptr inv = TMP_ALLOC_LIMBS(dn);
            mpn_invert(inv, dp, dn);
-           qh = mpn_inv_div_q (qp, np, nn, dp, dn, inv);
+           qh = mpn_inv_div_q (qp, new_np, nn, dp, dn, inv);
 	    }
 	  qp[nn - dn] = qh;
 	}
diff --git a/tests/mpn/Makefile.am b/tests/mpn/Makefile.am
index 4cda1a71..e5ac627f 100644
--- a/tests/mpn/Makefile.am
+++ b/tests/mpn/Makefile.am
@@ -28,7 +28,7 @@ check_PROGRAMS = t-asmtype t-aors_1 t-divrem_1 t-fat t-get_d \
   t-lorrshift1 t-divebyff t-addadd_n t-addsub_n t-subadd_n \
   t-redc_basecase t-divebyBm1of t-mullowhigh t-mullow_basecase \
   t-neg t-mulmod_2expp1 t-mulmod_2expm1 t-tdiv_q t-sb_divappr_q \
-  t-dc_divappr_q_n t-invert 
+  t-dc_divappr_q_n t-inv_divappr_q_n t-invert 
   
 if ENABLE_STATIC
 if ENABLE_SHARED
diff --git a/tests/mpn/Makefile.in b/tests/mpn/Makefile.in
index 0fa0db4b..7227dee1 100644
--- a/tests/mpn/Makefile.in
+++ b/tests/mpn/Makefile.in
@@ -61,7 +61,7 @@ check_PROGRAMS = t-asmtype$(EXEEXT) t-aors_1$(EXEEXT) \
 	t-neg$(EXEEXT) t-mulmod_2expp1$(EXEEXT) \
 	t-mulmod_2expm1$(EXEEXT) t-tdiv_q$(EXEEXT) \
 	t-sb_divappr_q$(EXEEXT) t-dc_divappr_q_n$(EXEEXT) \
-	t-invert$(EXEEXT) $(am__EXEEXT_1)
+	t-inv_divappr_q_n$(EXEEXT) t-invert$(EXEEXT) $(am__EXEEXT_1)
 @ENABLE_SHARED_TRUE@@ENABLE_STATIC_TRUE@am__append_1 = st_fat st_instrument
 subdir = tests/mpn
 DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
@@ -150,6 +150,11 @@ t_instrument_OBJECTS = t-instrument.$(OBJEXT)
 t_instrument_LDADD = $(LDADD)
 t_instrument_DEPENDENCIES = $(top_builddir)/tests/libtests.la \
 	$(top_builddir)/libmpir.la
+t_inv_divappr_q_n_SOURCES = t-inv_divappr_q_n.c
+t_inv_divappr_q_n_OBJECTS = t-inv_divappr_q_n.$(OBJEXT)
+t_inv_divappr_q_n_LDADD = $(LDADD)
+t_inv_divappr_q_n_DEPENDENCIES = $(top_builddir)/tests/libtests.la \
+	$(top_builddir)/libmpir.la
 t_invert_SOURCES = t-invert.c
 t_invert_OBJECTS = t-invert.$(OBJEXT)
 t_invert_LDADD = $(LDADD)
@@ -245,17 +250,17 @@ LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
 SOURCES = $(st_fat_SOURCES) $(st_instrument_SOURCES) t-addadd_n.c \
 	t-addsub_n.c t-aors_1.c t-asmtype.c t-dc_divappr_q_n.c \
 	t-divebyBm1of.c t-divebyff.c t-divrem_1.c t-fat.c t-get_d.c \
-	t-instrument.c t-invert.c t-iord_u.c t-lorrshift1.c \
-	t-mp_bases.c t-mullow_basecase.c t-mullowhigh.c t-mulmid.c \
-	t-mulmod_2expm1.c t-mulmod_2expp1.c t-neg.c t-perfsqr.c \
-	t-redc_basecase.c t-sb_divappr_q.c t-scan.c t-subadd_n.c \
-	t-tdiv_q.c
+	t-instrument.c t-inv_divappr_q_n.c t-invert.c t-iord_u.c \
+	t-lorrshift1.c t-mp_bases.c t-mullow_basecase.c t-mullowhigh.c \
+	t-mulmid.c t-mulmod_2expm1.c t-mulmod_2expp1.c t-neg.c \
+	t-perfsqr.c t-redc_basecase.c t-sb_divappr_q.c t-scan.c \
+	t-subadd_n.c t-tdiv_q.c
 DIST_SOURCES = $(am__st_fat_SOURCES_DIST) \
 	$(am__st_instrument_SOURCES_DIST) t-addadd_n.c t-addsub_n.c \
 	t-aors_1.c t-asmtype.c t-dc_divappr_q_n.c t-divebyBm1of.c \
 	t-divebyff.c t-divrem_1.c t-fat.c t-get_d.c t-instrument.c \
-	t-invert.c t-iord_u.c t-lorrshift1.c t-mp_bases.c \
-	t-mullow_basecase.c t-mullowhigh.c t-mulmid.c \
+	t-inv_divappr_q_n.c t-invert.c t-iord_u.c t-lorrshift1.c \
+	t-mp_bases.c t-mullow_basecase.c t-mullowhigh.c t-mulmid.c \
 	t-mulmod_2expm1.c t-mulmod_2expp1.c t-neg.c t-perfsqr.c \
 	t-redc_basecase.c t-sb_divappr_q.c t-scan.c t-subadd_n.c \
 	t-tdiv_q.c
@@ -500,6 +505,9 @@ t-get_d$(EXEEXT): $(t_get_d_OBJECTS) $(t_get_d_DEPENDENCIES)
 t-instrument$(EXEEXT): $(t_instrument_OBJECTS) $(t_instrument_DEPENDENCIES) 
 	@rm -f t-instrument$(EXEEXT)
 	$(LINK) $(t_instrument_OBJECTS) $(t_instrument_LDADD) $(LIBS)
+t-inv_divappr_q_n$(EXEEXT): $(t_inv_divappr_q_n_OBJECTS) $(t_inv_divappr_q_n_DEPENDENCIES) 
+	@rm -f t-inv_divappr_q_n$(EXEEXT)
+	$(LINK) $(t_inv_divappr_q_n_OBJECTS) $(t_inv_divappr_q_n_LDADD) $(LIBS)
 t-invert$(EXEEXT): $(t_invert_OBJECTS) $(t_invert_DEPENDENCIES) 
 	@rm -f t-invert$(EXEEXT)
 	$(LINK) $(t_invert_OBJECTS) $(t_invert_LDADD) $(LIBS)