From bc03a666203de25faf6246847fecbc8502267212 Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Sat, 6 Dec 2025 16:13:53 +0100 Subject: Add saturated arithmetic operations MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- libj2_j2u_sub_j2u.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) (limited to 'libj2_j2u_sub_j2u.c') diff --git a/libj2_j2u_sub_j2u.c b/libj2_j2u_sub_j2u.c index bd645e2..d69fb02 100644 --- a/libj2_j2u_sub_j2u.c +++ b/libj2_j2u_sub_j2u.c @@ -62,6 +62,12 @@ check_(uintmax_t a_high, uintmax_t a_low, uintmax_t b_high, uintmax_t b_low, EXPECT(libj2_j2u_eq_j2u(&a, &expected)); EXPECT(libj2_j2u_eq_j2u(&b, &b_saved)); + a = a_saved; + b = b_saved; + libj2_j2u_sat_sub_j2u(&a, &b); + EXPECT(r_overflow ? libj2_j2u_is_zero(&a) : libj2_j2u_eq_j2u(&a, &expected)); + EXPECT(libj2_j2u_eq_j2u(&b, &b_saved)); + a = a_saved; b = b_saved; EXPECT(libj2_j2u_sub_j2u_overflow_p((const struct libj2_j2u *)&a, (const struct libj2_j2u *)&b) == r_overflow); @@ -88,6 +94,26 @@ check_(uintmax_t a_high, uintmax_t a_low, uintmax_t b_high, uintmax_t b_low, EXPECT(libj2_j2u_eq_j2u(&b, &expected)); EXPECT(libj2_j2u_eq_j2u(&a, &a_saved)); + r = (struct libj2_j2u){111, 222}; + a = a_saved; + b = b_saved; + libj2_j2u_sat_sub_j2u_to_j2u(&a, &b, &r); + EXPECT(r_overflow ? libj2_j2u_is_zero(&r) : libj2_j2u_eq_j2u(&r, &expected)); + EXPECT(libj2_j2u_eq_j2u(&a, &a_saved)); + EXPECT(libj2_j2u_eq_j2u(&b, &b_saved)); + + a = a_saved; + b = b_saved; + libj2_j2u_sat_sub_j2u_to_j2u(&a, &b, &a); + EXPECT(r_overflow ? libj2_j2u_is_zero(&a) : libj2_j2u_eq_j2u(&a, &expected)); + EXPECT(libj2_j2u_eq_j2u(&b, &b_saved)); + + a = a_saved; + b = b_saved; + libj2_j2u_sat_sub_j2u_to_j2u(&a, &b, &b); + EXPECT(r_overflow ? libj2_j2u_is_zero(&b) : libj2_j2u_eq_j2u(&b, &expected)); + EXPECT(libj2_j2u_eq_j2u(&a, &a_saved)); + a = a_saved; b = b_saved; libj2_j2u_rsub_j2u(&b, &a); @@ -100,6 +126,12 @@ check_(uintmax_t a_high, uintmax_t a_low, uintmax_t b_high, uintmax_t b_low, EXPECT(libj2_j2u_eq_j2u(&b, &expected)); EXPECT(libj2_j2u_eq_j2u(&a, &a_saved)); + a = a_saved; + b = b_saved; + libj2_j2u_sat_rsub_j2u(&b, &a); + EXPECT(r_overflow ? libj2_j2u_is_zero(&b) : libj2_j2u_eq_j2u(&b, &expected)); + EXPECT(libj2_j2u_eq_j2u(&a, &a_saved)); + a = a_saved; b = b_saved; EXPECT(libj2_j2u_rsub_j2u_overflow_p(&b, &a) == r_overflow); @@ -160,6 +192,10 @@ check_double(uintmax_t high, uintmax_t low) EXPECT(libj2_j2u_sub_j2u_overflow(&a, &a) == 0); EXPECT(libj2_j2u_is_zero(&a)); + a = a_saved; + libj2_j2u_sat_sub_j2u(&a, &a); + EXPECT(libj2_j2u_is_zero(&a)); + a = a_saved; EXPECT(libj2_j2u_sub_j2u_overflow_p((const struct libj2_j2u *)&a, (const struct libj2_j2u *)&a) == 0); EXPECT(libj2_j2u_eq_j2u(&a, &a_saved)); @@ -174,6 +210,16 @@ check_double(uintmax_t high, uintmax_t low) EXPECT(libj2_j2u_sub_j2u_to_j2u_overflow(&a, &a, &a) == 0); EXPECT(libj2_j2u_is_zero(&a)); + r = (struct libj2_j2u){111, 222}; + a = a_saved; + libj2_j2u_sat_sub_j2u_to_j2u(&a, &a, &r); + EXPECT(libj2_j2u_is_zero(&r)); + EXPECT(libj2_j2u_eq_j2u(&a, &a_saved)); + + a = a_saved; + libj2_j2u_sat_sub_j2u_to_j2u(&a, &a, &a); + EXPECT(libj2_j2u_is_zero(&a)); + a = a_saved; libj2_j2u_rsub_j2u(&a, &a); EXPECT(libj2_j2u_is_zero(&a)); @@ -182,6 +228,10 @@ check_double(uintmax_t high, uintmax_t low) EXPECT(libj2_j2u_rsub_j2u_overflow(&a, &a) == 0); EXPECT(libj2_j2u_is_zero(&a)); + a = a_saved; + libj2_j2u_sat_rsub_j2u(&a, &a); + EXPECT(libj2_j2u_is_zero(&a)); + a = a_saved; EXPECT(libj2_j2u_rsub_j2u_overflow_p((const struct libj2_j2u *)&a, (const struct libj2_j2u *)&a) == 0); EXPECT(libj2_j2u_eq_j2u(&a, &a_saved)); -- cgit v1.2.3-70-g09d2