[PATCH v2 09/15] util: move 256-by-128 division helpers to int128

marcandre.lureau@redhat.com posted 15 patches 3 years, 7 months ago
Maintainers: Peter Maydell <peter.maydell@linaro.org>, Markus Armbruster <armbru@redhat.com>, Laurent Vivier <laurent@vivier.eu>, Michael Roth <michael.roth@amd.com>, Konstantin Kostiuk <kkostiuk@redhat.com>, John Snow <jsnow@redhat.com>, Cleber Rosa <crosa@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Xie Yongji <xieyongji@bytedance.com>
There is a newer version of this series
[PATCH v2 09/15] util: move 256-by-128 division helpers to int128
Posted by marcandre.lureau@redhat.com 3 years, 7 months ago
From: Marc-André Lureau <marcandre.lureau@redhat.com>

Break a cyclic dependency between int128 and host-utils.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/qemu/host-utils.h |   3 -
 include/qemu/int128.h     |   3 +
 util/host-utils.c         | 180 --------------------------------------
 util/int128.c             | 180 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 183 insertions(+), 183 deletions(-)

diff --git a/include/qemu/host-utils.h b/include/qemu/host-utils.h
index 29f3a9987880..fa228a4a86e2 100644
--- a/include/qemu/host-utils.h
+++ b/include/qemu/host-utils.h
@@ -32,7 +32,6 @@
 
 #include "qemu/compiler.h"
 #include "qemu/bswap.h"
-#include "qemu/int128.h"
 
 #ifdef CONFIG_INT128
 static inline void mulu64(uint64_t *plow, uint64_t *phigh,
@@ -785,6 +784,4 @@ static inline uint64_t udiv_qrnnd(uint64_t *r, uint64_t n1,
 #endif
 }
 
-Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor);
-Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor);
 #endif
diff --git a/include/qemu/int128.h b/include/qemu/int128.h
index d2b76ca6acdc..823c61edb0fd 100644
--- a/include/qemu/int128.h
+++ b/include/qemu/int128.h
@@ -472,4 +472,7 @@ static inline void bswap128s(Int128 *s)
 #define INT128_MAX int128_make128(UINT64_MAX, INT64_MAX)
 #define INT128_MIN int128_make128(0, INT64_MIN)
 
+Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor);
+Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor);
+
 #endif /* INT128_H */
diff --git a/util/host-utils.c b/util/host-utils.c
index fb91bcba823d..96d5dc0bed25 100644
--- a/util/host-utils.c
+++ b/util/host-utils.c
@@ -266,183 +266,3 @@ void ulshift(uint64_t *plow, uint64_t *phigh, int32_t shift, bool *overflow)
         *plow = *plow << shift;
     }
 }
-
-/*
- * Unsigned 256-by-128 division.
- * Returns the remainder via r.
- * Returns lower 128 bit of quotient.
- * Needs a normalized divisor (most significant bit set to 1).
- *
- * Adapted from include/qemu/host-utils.h udiv_qrnnd,
- * from the GNU Multi Precision Library - longlong.h __udiv_qrnnd
- * (https://gmplib.org/repo/gmp/file/tip/longlong.h)
- *
- * Licensed under the GPLv2/LGPLv3
- */
-static Int128 udiv256_qrnnd(Int128 *r, Int128 n1, Int128 n0, Int128 d)
-{
-    Int128 d0, d1, q0, q1, r1, r0, m;
-    uint64_t mp0, mp1;
-
-    d0 = int128_make64(int128_getlo(d));
-    d1 = int128_make64(int128_gethi(d));
-
-    r1 = int128_remu(n1, d1);
-    q1 = int128_divu(n1, d1);
-    mp0 = int128_getlo(q1);
-    mp1 = int128_gethi(q1);
-    mulu128(&mp0, &mp1, int128_getlo(d0));
-    m = int128_make128(mp0, mp1);
-    r1 = int128_make128(int128_gethi(n0), int128_getlo(r1));
-    if (int128_ult(r1, m)) {
-        q1 = int128_sub(q1, int128_one());
-        r1 = int128_add(r1, d);
-        if (int128_uge(r1, d)) {
-            if (int128_ult(r1, m)) {
-                q1 = int128_sub(q1, int128_one());
-                r1 = int128_add(r1, d);
-            }
-        }
-    }
-    r1 = int128_sub(r1, m);
-
-    r0 = int128_remu(r1, d1);
-    q0 = int128_divu(r1, d1);
-    mp0 = int128_getlo(q0);
-    mp1 = int128_gethi(q0);
-    mulu128(&mp0, &mp1, int128_getlo(d0));
-    m = int128_make128(mp0, mp1);
-    r0 = int128_make128(int128_getlo(n0), int128_getlo(r0));
-    if (int128_ult(r0, m)) {
-        q0 = int128_sub(q0, int128_one());
-        r0 = int128_add(r0, d);
-        if (int128_uge(r0, d)) {
-            if (int128_ult(r0, m)) {
-                q0 = int128_sub(q0, int128_one());
-                r0 = int128_add(r0, d);
-            }
-        }
-    }
-    r0 = int128_sub(r0, m);
-
-    *r = r0;
-    return int128_or(int128_lshift(q1, 64), q0);
-}
-
-/*
- * Unsigned 256-by-128 division.
- * Returns the remainder.
- * Returns quotient via plow and phigh.
- * Also returns the remainder via the function return value.
- */
-Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor)
-{
-    Int128 dhi = *phigh;
-    Int128 dlo = *plow;
-    Int128 rem, dhighest;
-    int sh;
-
-    if (!int128_nz(divisor) || !int128_nz(dhi)) {
-        *plow  = int128_divu(dlo, divisor);
-        *phigh = int128_zero();
-        return int128_remu(dlo, divisor);
-    } else {
-        sh = clz128(divisor);
-
-        if (int128_ult(dhi, divisor)) {
-            if (sh != 0) {
-                /* normalize the divisor, shifting the dividend accordingly */
-                divisor = int128_lshift(divisor, sh);
-                dhi = int128_or(int128_lshift(dhi, sh),
-                                int128_urshift(dlo, (128 - sh)));
-                dlo = int128_lshift(dlo, sh);
-            }
-
-            *phigh = int128_zero();
-            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
-        } else {
-            if (sh != 0) {
-                /* normalize the divisor, shifting the dividend accordingly */
-                divisor = int128_lshift(divisor, sh);
-                dhighest = int128_rshift(dhi, (128 - sh));
-                dhi = int128_or(int128_lshift(dhi, sh),
-                                int128_urshift(dlo, (128 - sh)));
-                dlo = int128_lshift(dlo, sh);
-
-                *phigh = udiv256_qrnnd(&dhi, dhighest, dhi, divisor);
-            } else {
-                /*
-                 * dhi >= divisor
-                 * Since the MSB of divisor is set (sh == 0),
-                 * (dhi - divisor) < divisor
-                 *
-                 * Thus, the high part of the quotient is 1, and we can
-                 * calculate the low part with a single call to udiv_qrnnd
-                 * after subtracting divisor from dhi
-                 */
-                dhi = int128_sub(dhi, divisor);
-                *phigh = int128_one();
-            }
-
-            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
-        }
-
-        /*
-         * since the dividend/divisor might have been normalized,
-         * the remainder might also have to be shifted back
-         */
-        rem = int128_urshift(rem, sh);
-        return rem;
-    }
-}
-
-/*
- * Signed 256-by-128 division.
- * Returns quotient via plow and phigh.
- * Also returns the remainder via the function return value.
- */
-Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor)
-{
-    bool neg_quotient = false, neg_remainder = false;
-    Int128 unsig_hi = *phigh, unsig_lo = *plow;
-    Int128 rem;
-
-    if (!int128_nonneg(*phigh)) {
-        neg_quotient = !neg_quotient;
-        neg_remainder = !neg_remainder;
-
-        if (!int128_nz(unsig_lo)) {
-            unsig_hi = int128_neg(unsig_hi);
-        } else {
-            unsig_hi = int128_not(unsig_hi);
-            unsig_lo = int128_neg(unsig_lo);
-        }
-    }
-
-    if (!int128_nonneg(divisor)) {
-        neg_quotient = !neg_quotient;
-
-        divisor = int128_neg(divisor);
-    }
-
-    rem = divu256(&unsig_lo, &unsig_hi, divisor);
-
-    if (neg_quotient) {
-        if (!int128_nz(unsig_lo)) {
-            *phigh = int128_neg(unsig_hi);
-            *plow = int128_zero();
-        } else {
-            *phigh = int128_not(unsig_hi);
-            *plow = int128_neg(unsig_lo);
-        }
-    } else {
-        *phigh = unsig_hi;
-        *plow = unsig_lo;
-    }
-
-    if (neg_remainder) {
-        return int128_neg(rem);
-    } else {
-        return rem;
-    }
-}
diff --git a/util/int128.c b/util/int128.c
index ed8f25fef161..482c63b6551e 100644
--- a/util/int128.c
+++ b/util/int128.c
@@ -145,3 +145,183 @@ Int128 int128_rems(Int128 a, Int128 b)
 }
 
 #endif
+
+/*
+ * Unsigned 256-by-128 division.
+ * Returns the remainder via r.
+ * Returns lower 128 bit of quotient.
+ * Needs a normalized divisor (most significant bit set to 1).
+ *
+ * Adapted from include/qemu/host-utils.h udiv_qrnnd,
+ * from the GNU Multi Precision Library - longlong.h __udiv_qrnnd
+ * (https://gmplib.org/repo/gmp/file/tip/longlong.h)
+ *
+ * Licensed under the GPLv2/LGPLv3
+ */
+static Int128 udiv256_qrnnd(Int128 *r, Int128 n1, Int128 n0, Int128 d)
+{
+    Int128 d0, d1, q0, q1, r1, r0, m;
+    uint64_t mp0, mp1;
+
+    d0 = int128_make64(int128_getlo(d));
+    d1 = int128_make64(int128_gethi(d));
+
+    r1 = int128_remu(n1, d1);
+    q1 = int128_divu(n1, d1);
+    mp0 = int128_getlo(q1);
+    mp1 = int128_gethi(q1);
+    mulu128(&mp0, &mp1, int128_getlo(d0));
+    m = int128_make128(mp0, mp1);
+    r1 = int128_make128(int128_gethi(n0), int128_getlo(r1));
+    if (int128_ult(r1, m)) {
+        q1 = int128_sub(q1, int128_one());
+        r1 = int128_add(r1, d);
+        if (int128_uge(r1, d)) {
+            if (int128_ult(r1, m)) {
+                q1 = int128_sub(q1, int128_one());
+                r1 = int128_add(r1, d);
+            }
+        }
+    }
+    r1 = int128_sub(r1, m);
+
+    r0 = int128_remu(r1, d1);
+    q0 = int128_divu(r1, d1);
+    mp0 = int128_getlo(q0);
+    mp1 = int128_gethi(q0);
+    mulu128(&mp0, &mp1, int128_getlo(d0));
+    m = int128_make128(mp0, mp1);
+    r0 = int128_make128(int128_getlo(n0), int128_getlo(r0));
+    if (int128_ult(r0, m)) {
+        q0 = int128_sub(q0, int128_one());
+        r0 = int128_add(r0, d);
+        if (int128_uge(r0, d)) {
+            if (int128_ult(r0, m)) {
+                q0 = int128_sub(q0, int128_one());
+                r0 = int128_add(r0, d);
+            }
+        }
+    }
+    r0 = int128_sub(r0, m);
+
+    *r = r0;
+    return int128_or(int128_lshift(q1, 64), q0);
+}
+
+/*
+ * Unsigned 256-by-128 division.
+ * Returns the remainder.
+ * Returns quotient via plow and phigh.
+ * Also returns the remainder via the function return value.
+ */
+Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor)
+{
+    Int128 dhi = *phigh;
+    Int128 dlo = *plow;
+    Int128 rem, dhighest;
+    int sh;
+
+    if (!int128_nz(divisor) || !int128_nz(dhi)) {
+        *plow  = int128_divu(dlo, divisor);
+        *phigh = int128_zero();
+        return int128_remu(dlo, divisor);
+    } else {
+        sh = clz128(divisor);
+
+        if (int128_ult(dhi, divisor)) {
+            if (sh != 0) {
+                /* normalize the divisor, shifting the dividend accordingly */
+                divisor = int128_lshift(divisor, sh);
+                dhi = int128_or(int128_lshift(dhi, sh),
+                                int128_urshift(dlo, (128 - sh)));
+                dlo = int128_lshift(dlo, sh);
+            }
+
+            *phigh = int128_zero();
+            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
+        } else {
+            if (sh != 0) {
+                /* normalize the divisor, shifting the dividend accordingly */
+                divisor = int128_lshift(divisor, sh);
+                dhighest = int128_rshift(dhi, (128 - sh));
+                dhi = int128_or(int128_lshift(dhi, sh),
+                                int128_urshift(dlo, (128 - sh)));
+                dlo = int128_lshift(dlo, sh);
+
+                *phigh = udiv256_qrnnd(&dhi, dhighest, dhi, divisor);
+            } else {
+                /*
+                 * dhi >= divisor
+                 * Since the MSB of divisor is set (sh == 0),
+                 * (dhi - divisor) < divisor
+                 *
+                 * Thus, the high part of the quotient is 1, and we can
+                 * calculate the low part with a single call to udiv_qrnnd
+                 * after subtracting divisor from dhi
+                 */
+                dhi = int128_sub(dhi, divisor);
+                *phigh = int128_one();
+            }
+
+            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
+        }
+
+        /*
+         * since the dividend/divisor might have been normalized,
+         * the remainder might also have to be shifted back
+         */
+        rem = int128_urshift(rem, sh);
+        return rem;
+    }
+}
+
+/*
+ * Signed 256-by-128 division.
+ * Returns quotient via plow and phigh.
+ * Also returns the remainder via the function return value.
+ */
+Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor)
+{
+    bool neg_quotient = false, neg_remainder = false;
+    Int128 unsig_hi = *phigh, unsig_lo = *plow;
+    Int128 rem;
+
+    if (!int128_nonneg(*phigh)) {
+        neg_quotient = !neg_quotient;
+        neg_remainder = !neg_remainder;
+
+        if (!int128_nz(unsig_lo)) {
+            unsig_hi = int128_neg(unsig_hi);
+        } else {
+            unsig_hi = int128_not(unsig_hi);
+            unsig_lo = int128_neg(unsig_lo);
+        }
+    }
+
+    if (!int128_nonneg(divisor)) {
+        neg_quotient = !neg_quotient;
+
+        divisor = int128_neg(divisor);
+    }
+
+    rem = divu256(&unsig_lo, &unsig_hi, divisor);
+
+    if (neg_quotient) {
+        if (!int128_nz(unsig_lo)) {
+            *phigh = int128_neg(unsig_hi);
+            *plow = int128_zero();
+        } else {
+            *phigh = int128_not(unsig_hi);
+            *plow = int128_neg(unsig_lo);
+        }
+    } else {
+        *phigh = unsig_hi;
+        *plow = unsig_lo;
+    }
+
+    if (neg_remainder) {
+        return int128_neg(rem);
+    } else {
+        return rem;
+    }
+}
-- 
2.37.0.rc0


Re: [PATCH v2 09/15] util: move 256-by-128 division helpers to int128
Posted by Lucas Mateus Martins Araujo e Castro 3 years, 6 months ago
On 12/07/2022 06:35, marcandre.lureau@redhat.com wrote:
> From: Marc-André Lureau<marcandre.lureau@redhat.com>
>
> Break a cyclic dependency between int128 and host-utils.
Reviewed-by: Lucas Mateus Castro <lucas.araujo@eldorado.org.br>
>
> Signed-off-by: Marc-André Lureau<marcandre.lureau@redhat.com>
> ---
>   include/qemu/host-utils.h |   3 -
>   include/qemu/int128.h     |   3 +
>   util/host-utils.c         | 180 --------------------------------------
>   util/int128.c             | 180 ++++++++++++++++++++++++++++++++++++++
>   4 files changed, 183 insertions(+), 183 deletions(-)
>
> diff --git a/include/qemu/host-utils.h b/include/qemu/host-utils.h
> index 29f3a9987880..fa228a4a86e2 100644
> --- a/include/qemu/host-utils.h
> +++ b/include/qemu/host-utils.h
> @@ -32,7 +32,6 @@
>
>   #include "qemu/compiler.h"
>   #include "qemu/bswap.h"
> -#include "qemu/int128.h"
>
>   #ifdef CONFIG_INT128
>   static inline void mulu64(uint64_t *plow, uint64_t *phigh,
> @@ -785,6 +784,4 @@ static inline uint64_t udiv_qrnnd(uint64_t *r, uint64_t n1,
>   #endif
>   }
>
> -Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor);
> -Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor);
>   #endif
> diff --git a/include/qemu/int128.h b/include/qemu/int128.h
> index d2b76ca6acdc..823c61edb0fd 100644
> --- a/include/qemu/int128.h
> +++ b/include/qemu/int128.h
> @@ -472,4 +472,7 @@ static inline void bswap128s(Int128 *s)
>   #define INT128_MAX int128_make128(UINT64_MAX, INT64_MAX)
>   #define INT128_MIN int128_make128(0, INT64_MIN)
>
> +Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor);
> +Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor);
> +
>   #endif /* INT128_H */
> diff --git a/util/host-utils.c b/util/host-utils.c
> index fb91bcba823d..96d5dc0bed25 100644
> --- a/util/host-utils.c
> +++ b/util/host-utils.c
> @@ -266,183 +266,3 @@ void ulshift(uint64_t *plow, uint64_t *phigh, int32_t shift, bool *overflow)
>           *plow = *plow << shift;
>       }
>   }
> -
> -/*
> - * Unsigned 256-by-128 division.
> - * Returns the remainder via r.
> - * Returns lower 128 bit of quotient.
> - * Needs a normalized divisor (most significant bit set to 1).
> - *
> - * Adapted from include/qemu/host-utils.h udiv_qrnnd,
> - * from the GNU Multi Precision Library - longlong.h __udiv_qrnnd
> - * (https://gmplib.org/repo/gmp/file/tip/longlong.h)
> - *
> - * Licensed under the GPLv2/LGPLv3
> - */
> -static Int128 udiv256_qrnnd(Int128 *r, Int128 n1, Int128 n0, Int128 d)
> -{
> -    Int128 d0, d1, q0, q1, r1, r0, m;
> -    uint64_t mp0, mp1;
> -
> -    d0 = int128_make64(int128_getlo(d));
> -    d1 = int128_make64(int128_gethi(d));
> -
> -    r1 = int128_remu(n1, d1);
> -    q1 = int128_divu(n1, d1);
> -    mp0 = int128_getlo(q1);
> -    mp1 = int128_gethi(q1);
> -    mulu128(&mp0, &mp1, int128_getlo(d0));
> -    m = int128_make128(mp0, mp1);
> -    r1 = int128_make128(int128_gethi(n0), int128_getlo(r1));
> -    if (int128_ult(r1, m)) {
> -        q1 = int128_sub(q1, int128_one());
> -        r1 = int128_add(r1, d);
> -        if (int128_uge(r1, d)) {
> -            if (int128_ult(r1, m)) {
> -                q1 = int128_sub(q1, int128_one());
> -                r1 = int128_add(r1, d);
> -            }
> -        }
> -    }
> -    r1 = int128_sub(r1, m);
> -
> -    r0 = int128_remu(r1, d1);
> -    q0 = int128_divu(r1, d1);
> -    mp0 = int128_getlo(q0);
> -    mp1 = int128_gethi(q0);
> -    mulu128(&mp0, &mp1, int128_getlo(d0));
> -    m = int128_make128(mp0, mp1);
> -    r0 = int128_make128(int128_getlo(n0), int128_getlo(r0));
> -    if (int128_ult(r0, m)) {
> -        q0 = int128_sub(q0, int128_one());
> -        r0 = int128_add(r0, d);
> -        if (int128_uge(r0, d)) {
> -            if (int128_ult(r0, m)) {
> -                q0 = int128_sub(q0, int128_one());
> -                r0 = int128_add(r0, d);
> -            }
> -        }
> -    }
> -    r0 = int128_sub(r0, m);
> -
> -    *r = r0;
> -    return int128_or(int128_lshift(q1, 64), q0);
> -}
> -
> -/*
> - * Unsigned 256-by-128 division.
> - * Returns the remainder.
> - * Returns quotient via plow and phigh.
> - * Also returns the remainder via the function return value.
> - */
> -Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor)
> -{
> -    Int128 dhi = *phigh;
> -    Int128 dlo = *plow;
> -    Int128 rem, dhighest;
> -    int sh;
> -
> -    if (!int128_nz(divisor) || !int128_nz(dhi)) {
> -        *plow  = int128_divu(dlo, divisor);
> -        *phigh = int128_zero();
> -        return int128_remu(dlo, divisor);
> -    } else {
> -        sh = clz128(divisor);
> -
> -        if (int128_ult(dhi, divisor)) {
> -            if (sh != 0) {
> -                /* normalize the divisor, shifting the dividend accordingly */
> -                divisor = int128_lshift(divisor, sh);
> -                dhi = int128_or(int128_lshift(dhi, sh),
> -                                int128_urshift(dlo, (128 - sh)));
> -                dlo = int128_lshift(dlo, sh);
> -            }
> -
> -            *phigh = int128_zero();
> -            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
> -        } else {
> -            if (sh != 0) {
> -                /* normalize the divisor, shifting the dividend accordingly */
> -                divisor = int128_lshift(divisor, sh);
> -                dhighest = int128_rshift(dhi, (128 - sh));
> -                dhi = int128_or(int128_lshift(dhi, sh),
> -                                int128_urshift(dlo, (128 - sh)));
> -                dlo = int128_lshift(dlo, sh);
> -
> -                *phigh = udiv256_qrnnd(&dhi, dhighest, dhi, divisor);
> -            } else {
> -                /*
> -                 * dhi >= divisor
> -                 * Since the MSB of divisor is set (sh == 0),
> -                 * (dhi - divisor) < divisor
> -                 *
> -                 * Thus, the high part of the quotient is 1, and we can
> -                 * calculate the low part with a single call to udiv_qrnnd
> -                 * after subtracting divisor from dhi
> -                 */
> -                dhi = int128_sub(dhi, divisor);
> -                *phigh = int128_one();
> -            }
> -
> -            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
> -        }
> -
> -        /*
> -         * since the dividend/divisor might have been normalized,
> -         * the remainder might also have to be shifted back
> -         */
> -        rem = int128_urshift(rem, sh);
> -        return rem;
> -    }
> -}
> -
> -/*
> - * Signed 256-by-128 division.
> - * Returns quotient via plow and phigh.
> - * Also returns the remainder via the function return value.
> - */
> -Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor)
> -{
> -    bool neg_quotient = false, neg_remainder = false;
> -    Int128 unsig_hi = *phigh, unsig_lo = *plow;
> -    Int128 rem;
> -
> -    if (!int128_nonneg(*phigh)) {
> -        neg_quotient = !neg_quotient;
> -        neg_remainder = !neg_remainder;
> -
> -        if (!int128_nz(unsig_lo)) {
> -            unsig_hi = int128_neg(unsig_hi);
> -        } else {
> -            unsig_hi = int128_not(unsig_hi);
> -            unsig_lo = int128_neg(unsig_lo);
> -        }
> -    }
> -
> -    if (!int128_nonneg(divisor)) {
> -        neg_quotient = !neg_quotient;
> -
> -        divisor = int128_neg(divisor);
> -    }
> -
> -    rem = divu256(&unsig_lo, &unsig_hi, divisor);
> -
> -    if (neg_quotient) {
> -        if (!int128_nz(unsig_lo)) {
> -            *phigh = int128_neg(unsig_hi);
> -            *plow = int128_zero();
> -        } else {
> -            *phigh = int128_not(unsig_hi);
> -            *plow = int128_neg(unsig_lo);
> -        }
> -    } else {
> -        *phigh = unsig_hi;
> -        *plow = unsig_lo;
> -    }
> -
> -    if (neg_remainder) {
> -        return int128_neg(rem);
> -    } else {
> -        return rem;
> -    }
> -}
> diff --git a/util/int128.c b/util/int128.c
> index ed8f25fef161..482c63b6551e 100644
> --- a/util/int128.c
> +++ b/util/int128.c
> @@ -145,3 +145,183 @@ Int128 int128_rems(Int128 a, Int128 b)
>   }
>
>   #endif
> +
> +/*
> + * Unsigned 256-by-128 division.
> + * Returns the remainder via r.
> + * Returns lower 128 bit of quotient.
> + * Needs a normalized divisor (most significant bit set to 1).
> + *
> + * Adapted from include/qemu/host-utils.h udiv_qrnnd,
> + * from the GNU Multi Precision Library - longlong.h __udiv_qrnnd
> + * (https://gmplib.org/repo/gmp/file/tip/longlong.h)
> + *
> + * Licensed under the GPLv2/LGPLv3
> + */
> +static Int128 udiv256_qrnnd(Int128 *r, Int128 n1, Int128 n0, Int128 d)
> +{
> +    Int128 d0, d1, q0, q1, r1, r0, m;
> +    uint64_t mp0, mp1;
> +
> +    d0 = int128_make64(int128_getlo(d));
> +    d1 = int128_make64(int128_gethi(d));
> +
> +    r1 = int128_remu(n1, d1);
> +    q1 = int128_divu(n1, d1);
> +    mp0 = int128_getlo(q1);
> +    mp1 = int128_gethi(q1);
> +    mulu128(&mp0, &mp1, int128_getlo(d0));
> +    m = int128_make128(mp0, mp1);
> +    r1 = int128_make128(int128_gethi(n0), int128_getlo(r1));
> +    if (int128_ult(r1, m)) {
> +        q1 = int128_sub(q1, int128_one());
> +        r1 = int128_add(r1, d);
> +        if (int128_uge(r1, d)) {
> +            if (int128_ult(r1, m)) {
> +                q1 = int128_sub(q1, int128_one());
> +                r1 = int128_add(r1, d);
> +            }
> +        }
> +    }
> +    r1 = int128_sub(r1, m);
> +
> +    r0 = int128_remu(r1, d1);
> +    q0 = int128_divu(r1, d1);
> +    mp0 = int128_getlo(q0);
> +    mp1 = int128_gethi(q0);
> +    mulu128(&mp0, &mp1, int128_getlo(d0));
> +    m = int128_make128(mp0, mp1);
> +    r0 = int128_make128(int128_getlo(n0), int128_getlo(r0));
> +    if (int128_ult(r0, m)) {
> +        q0 = int128_sub(q0, int128_one());
> +        r0 = int128_add(r0, d);
> +        if (int128_uge(r0, d)) {
> +            if (int128_ult(r0, m)) {
> +                q0 = int128_sub(q0, int128_one());
> +                r0 = int128_add(r0, d);
> +            }
> +        }
> +    }
> +    r0 = int128_sub(r0, m);
> +
> +    *r = r0;
> +    return int128_or(int128_lshift(q1, 64), q0);
> +}
> +
> +/*
> + * Unsigned 256-by-128 division.
> + * Returns the remainder.
> + * Returns quotient via plow and phigh.
> + * Also returns the remainder via the function return value.
> + */
> +Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor)
> +{
> +    Int128 dhi = *phigh;
> +    Int128 dlo = *plow;
> +    Int128 rem, dhighest;
> +    int sh;
> +
> +    if (!int128_nz(divisor) || !int128_nz(dhi)) {
> +        *plow  = int128_divu(dlo, divisor);
> +        *phigh = int128_zero();
> +        return int128_remu(dlo, divisor);
> +    } else {
> +        sh = clz128(divisor);
> +
> +        if (int128_ult(dhi, divisor)) {
> +            if (sh != 0) {
> +                /* normalize the divisor, shifting the dividend accordingly */
> +                divisor = int128_lshift(divisor, sh);
> +                dhi = int128_or(int128_lshift(dhi, sh),
> +                                int128_urshift(dlo, (128 - sh)));
> +                dlo = int128_lshift(dlo, sh);
> +            }
> +
> +            *phigh = int128_zero();
> +            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
> +        } else {
> +            if (sh != 0) {
> +                /* normalize the divisor, shifting the dividend accordingly */
> +                divisor = int128_lshift(divisor, sh);
> +                dhighest = int128_rshift(dhi, (128 - sh));
> +                dhi = int128_or(int128_lshift(dhi, sh),
> +                                int128_urshift(dlo, (128 - sh)));
> +                dlo = int128_lshift(dlo, sh);
> +
> +                *phigh = udiv256_qrnnd(&dhi, dhighest, dhi, divisor);
> +            } else {
> +                /*
> +                 * dhi >= divisor
> +                 * Since the MSB of divisor is set (sh == 0),
> +                 * (dhi - divisor) < divisor
> +                 *
> +                 * Thus, the high part of the quotient is 1, and we can
> +                 * calculate the low part with a single call to udiv_qrnnd
> +                 * after subtracting divisor from dhi
> +                 */
> +                dhi = int128_sub(dhi, divisor);
> +                *phigh = int128_one();
> +            }
> +
> +            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
> +        }
> +
> +        /*
> +         * since the dividend/divisor might have been normalized,
> +         * the remainder might also have to be shifted back
> +         */
> +        rem = int128_urshift(rem, sh);
> +        return rem;
> +    }
> +}
> +
> +/*
> + * Signed 256-by-128 division.
> + * Returns quotient via plow and phigh.
> + * Also returns the remainder via the function return value.
> + */
> +Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor)
> +{
> +    bool neg_quotient = false, neg_remainder = false;
> +    Int128 unsig_hi = *phigh, unsig_lo = *plow;
> +    Int128 rem;
> +
> +    if (!int128_nonneg(*phigh)) {
> +        neg_quotient = !neg_quotient;
> +        neg_remainder = !neg_remainder;
> +
> +        if (!int128_nz(unsig_lo)) {
> +            unsig_hi = int128_neg(unsig_hi);
> +        } else {
> +            unsig_hi = int128_not(unsig_hi);
> +            unsig_lo = int128_neg(unsig_lo);
> +        }
> +    }
> +
> +    if (!int128_nonneg(divisor)) {
> +        neg_quotient = !neg_quotient;
> +
> +        divisor = int128_neg(divisor);
> +    }
> +
> +    rem = divu256(&unsig_lo, &unsig_hi, divisor);
> +
> +    if (neg_quotient) {
> +        if (!int128_nz(unsig_lo)) {
> +            *phigh = int128_neg(unsig_hi);
> +            *plow = int128_zero();
> +        } else {
> +            *phigh = int128_not(unsig_hi);
> +            *plow = int128_neg(unsig_lo);
> +        }
> +    } else {
> +        *phigh = unsig_hi;
> +        *plow = unsig_lo;
> +    }
> +
> +    if (neg_remainder) {
> +        return int128_neg(rem);
> +    } else {
> +        return rem;
> +    }
> +}
> --
> 2.37.0.rc0
>
>
-- 
Lucas Mateus M. Araujo e Castro
Instituto de Pesquisas ELDORADO 
<https://www.eldorado.org.br/?utm_campaign=assinatura_de_e-mail&utm_medium=email&utm_source=RD+Station>
Departamento Computação Embarcada
Analista de Software Trainee
Aviso Legal - Disclaimer <https://www.eldorado.org.br/disclaimer.html>
Re: [PATCH v2 09/15] util: move 256-by-128 division helpers to int128
Posted by Marc-André Lureau 3 years, 6 months ago
Hi


On Tue, Jul 12, 2022 at 1:49 PM <marcandre.lureau@redhat.com> wrote:

> From: Marc-André Lureau <marcandre.lureau@redhat.com>
>
> Break a cyclic dependency between int128 and host-utils.
>

Anyone to approve that change? (This will allow us to more easily move
host-utils & int128 units to a subproject)
thanks


>
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  include/qemu/host-utils.h |   3 -
>  include/qemu/int128.h     |   3 +
>  util/host-utils.c         | 180 --------------------------------------
>  util/int128.c             | 180 ++++++++++++++++++++++++++++++++++++++
>  4 files changed, 183 insertions(+), 183 deletions(-)
>
> diff --git a/include/qemu/host-utils.h b/include/qemu/host-utils.h
> index 29f3a9987880..fa228a4a86e2 100644
> --- a/include/qemu/host-utils.h
> +++ b/include/qemu/host-utils.h
> @@ -32,7 +32,6 @@
>
>  #include "qemu/compiler.h"
>  #include "qemu/bswap.h"
> -#include "qemu/int128.h"
>
>  #ifdef CONFIG_INT128
>  static inline void mulu64(uint64_t *plow, uint64_t *phigh,
> @@ -785,6 +784,4 @@ static inline uint64_t udiv_qrnnd(uint64_t *r,
> uint64_t n1,
>  #endif
>  }
>
> -Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor);
> -Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor);
>  #endif
> diff --git a/include/qemu/int128.h b/include/qemu/int128.h
> index d2b76ca6acdc..823c61edb0fd 100644
> --- a/include/qemu/int128.h
> +++ b/include/qemu/int128.h
> @@ -472,4 +472,7 @@ static inline void bswap128s(Int128 *s)
>  #define INT128_MAX int128_make128(UINT64_MAX, INT64_MAX)
>  #define INT128_MIN int128_make128(0, INT64_MIN)
>
> +Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor);
> +Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor);
> +
>  #endif /* INT128_H */
> diff --git a/util/host-utils.c b/util/host-utils.c
> index fb91bcba823d..96d5dc0bed25 100644
> --- a/util/host-utils.c
> +++ b/util/host-utils.c
> @@ -266,183 +266,3 @@ void ulshift(uint64_t *plow, uint64_t *phigh,
> int32_t shift, bool *overflow)
>          *plow = *plow << shift;
>      }
>  }
> -
> -/*
> - * Unsigned 256-by-128 division.
> - * Returns the remainder via r.
> - * Returns lower 128 bit of quotient.
> - * Needs a normalized divisor (most significant bit set to 1).
> - *
> - * Adapted from include/qemu/host-utils.h udiv_qrnnd,
> - * from the GNU Multi Precision Library - longlong.h __udiv_qrnnd
> - * (https://gmplib.org/repo/gmp/file/tip/longlong.h)
> - *
> - * Licensed under the GPLv2/LGPLv3
> - */
> -static Int128 udiv256_qrnnd(Int128 *r, Int128 n1, Int128 n0, Int128 d)
> -{
> -    Int128 d0, d1, q0, q1, r1, r0, m;
> -    uint64_t mp0, mp1;
> -
> -    d0 = int128_make64(int128_getlo(d));
> -    d1 = int128_make64(int128_gethi(d));
> -
> -    r1 = int128_remu(n1, d1);
> -    q1 = int128_divu(n1, d1);
> -    mp0 = int128_getlo(q1);
> -    mp1 = int128_gethi(q1);
> -    mulu128(&mp0, &mp1, int128_getlo(d0));
> -    m = int128_make128(mp0, mp1);
> -    r1 = int128_make128(int128_gethi(n0), int128_getlo(r1));
> -    if (int128_ult(r1, m)) {
> -        q1 = int128_sub(q1, int128_one());
> -        r1 = int128_add(r1, d);
> -        if (int128_uge(r1, d)) {
> -            if (int128_ult(r1, m)) {
> -                q1 = int128_sub(q1, int128_one());
> -                r1 = int128_add(r1, d);
> -            }
> -        }
> -    }
> -    r1 = int128_sub(r1, m);
> -
> -    r0 = int128_remu(r1, d1);
> -    q0 = int128_divu(r1, d1);
> -    mp0 = int128_getlo(q0);
> -    mp1 = int128_gethi(q0);
> -    mulu128(&mp0, &mp1, int128_getlo(d0));
> -    m = int128_make128(mp0, mp1);
> -    r0 = int128_make128(int128_getlo(n0), int128_getlo(r0));
> -    if (int128_ult(r0, m)) {
> -        q0 = int128_sub(q0, int128_one());
> -        r0 = int128_add(r0, d);
> -        if (int128_uge(r0, d)) {
> -            if (int128_ult(r0, m)) {
> -                q0 = int128_sub(q0, int128_one());
> -                r0 = int128_add(r0, d);
> -            }
> -        }
> -    }
> -    r0 = int128_sub(r0, m);
> -
> -    *r = r0;
> -    return int128_or(int128_lshift(q1, 64), q0);
> -}
> -
> -/*
> - * Unsigned 256-by-128 division.
> - * Returns the remainder.
> - * Returns quotient via plow and phigh.
> - * Also returns the remainder via the function return value.
> - */
> -Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor)
> -{
> -    Int128 dhi = *phigh;
> -    Int128 dlo = *plow;
> -    Int128 rem, dhighest;
> -    int sh;
> -
> -    if (!int128_nz(divisor) || !int128_nz(dhi)) {
> -        *plow  = int128_divu(dlo, divisor);
> -        *phigh = int128_zero();
> -        return int128_remu(dlo, divisor);
> -    } else {
> -        sh = clz128(divisor);
> -
> -        if (int128_ult(dhi, divisor)) {
> -            if (sh != 0) {
> -                /* normalize the divisor, shifting the dividend
> accordingly */
> -                divisor = int128_lshift(divisor, sh);
> -                dhi = int128_or(int128_lshift(dhi, sh),
> -                                int128_urshift(dlo, (128 - sh)));
> -                dlo = int128_lshift(dlo, sh);
> -            }
> -
> -            *phigh = int128_zero();
> -            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
> -        } else {
> -            if (sh != 0) {
> -                /* normalize the divisor, shifting the dividend
> accordingly */
> -                divisor = int128_lshift(divisor, sh);
> -                dhighest = int128_rshift(dhi, (128 - sh));
> -                dhi = int128_or(int128_lshift(dhi, sh),
> -                                int128_urshift(dlo, (128 - sh)));
> -                dlo = int128_lshift(dlo, sh);
> -
> -                *phigh = udiv256_qrnnd(&dhi, dhighest, dhi, divisor);
> -            } else {
> -                /*
> -                 * dhi >= divisor
> -                 * Since the MSB of divisor is set (sh == 0),
> -                 * (dhi - divisor) < divisor
> -                 *
> -                 * Thus, the high part of the quotient is 1, and we can
> -                 * calculate the low part with a single call to udiv_qrnnd
> -                 * after subtracting divisor from dhi
> -                 */
> -                dhi = int128_sub(dhi, divisor);
> -                *phigh = int128_one();
> -            }
> -
> -            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
> -        }
> -
> -        /*
> -         * since the dividend/divisor might have been normalized,
> -         * the remainder might also have to be shifted back
> -         */
> -        rem = int128_urshift(rem, sh);
> -        return rem;
> -    }
> -}
> -
> -/*
> - * Signed 256-by-128 division.
> - * Returns quotient via plow and phigh.
> - * Also returns the remainder via the function return value.
> - */
> -Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor)
> -{
> -    bool neg_quotient = false, neg_remainder = false;
> -    Int128 unsig_hi = *phigh, unsig_lo = *plow;
> -    Int128 rem;
> -
> -    if (!int128_nonneg(*phigh)) {
> -        neg_quotient = !neg_quotient;
> -        neg_remainder = !neg_remainder;
> -
> -        if (!int128_nz(unsig_lo)) {
> -            unsig_hi = int128_neg(unsig_hi);
> -        } else {
> -            unsig_hi = int128_not(unsig_hi);
> -            unsig_lo = int128_neg(unsig_lo);
> -        }
> -    }
> -
> -    if (!int128_nonneg(divisor)) {
> -        neg_quotient = !neg_quotient;
> -
> -        divisor = int128_neg(divisor);
> -    }
> -
> -    rem = divu256(&unsig_lo, &unsig_hi, divisor);
> -
> -    if (neg_quotient) {
> -        if (!int128_nz(unsig_lo)) {
> -            *phigh = int128_neg(unsig_hi);
> -            *plow = int128_zero();
> -        } else {
> -            *phigh = int128_not(unsig_hi);
> -            *plow = int128_neg(unsig_lo);
> -        }
> -    } else {
> -        *phigh = unsig_hi;
> -        *plow = unsig_lo;
> -    }
> -
> -    if (neg_remainder) {
> -        return int128_neg(rem);
> -    } else {
> -        return rem;
> -    }
> -}
> diff --git a/util/int128.c b/util/int128.c
> index ed8f25fef161..482c63b6551e 100644
> --- a/util/int128.c
> +++ b/util/int128.c
> @@ -145,3 +145,183 @@ Int128 int128_rems(Int128 a, Int128 b)
>  }
>
>  #endif
> +
> +/*
> + * Unsigned 256-by-128 division.
> + * Returns the remainder via r.
> + * Returns lower 128 bit of quotient.
> + * Needs a normalized divisor (most significant bit set to 1).
> + *
> + * Adapted from include/qemu/host-utils.h udiv_qrnnd,
> + * from the GNU Multi Precision Library - longlong.h __udiv_qrnnd
> + * (https://gmplib.org/repo/gmp/file/tip/longlong.h)
> + *
> + * Licensed under the GPLv2/LGPLv3
> + */
> +static Int128 udiv256_qrnnd(Int128 *r, Int128 n1, Int128 n0, Int128 d)
> +{
> +    Int128 d0, d1, q0, q1, r1, r0, m;
> +    uint64_t mp0, mp1;
> +
> +    d0 = int128_make64(int128_getlo(d));
> +    d1 = int128_make64(int128_gethi(d));
> +
> +    r1 = int128_remu(n1, d1);
> +    q1 = int128_divu(n1, d1);
> +    mp0 = int128_getlo(q1);
> +    mp1 = int128_gethi(q1);
> +    mulu128(&mp0, &mp1, int128_getlo(d0));
> +    m = int128_make128(mp0, mp1);
> +    r1 = int128_make128(int128_gethi(n0), int128_getlo(r1));
> +    if (int128_ult(r1, m)) {
> +        q1 = int128_sub(q1, int128_one());
> +        r1 = int128_add(r1, d);
> +        if (int128_uge(r1, d)) {
> +            if (int128_ult(r1, m)) {
> +                q1 = int128_sub(q1, int128_one());
> +                r1 = int128_add(r1, d);
> +            }
> +        }
> +    }
> +    r1 = int128_sub(r1, m);
> +
> +    r0 = int128_remu(r1, d1);
> +    q0 = int128_divu(r1, d1);
> +    mp0 = int128_getlo(q0);
> +    mp1 = int128_gethi(q0);
> +    mulu128(&mp0, &mp1, int128_getlo(d0));
> +    m = int128_make128(mp0, mp1);
> +    r0 = int128_make128(int128_getlo(n0), int128_getlo(r0));
> +    if (int128_ult(r0, m)) {
> +        q0 = int128_sub(q0, int128_one());
> +        r0 = int128_add(r0, d);
> +        if (int128_uge(r0, d)) {
> +            if (int128_ult(r0, m)) {
> +                q0 = int128_sub(q0, int128_one());
> +                r0 = int128_add(r0, d);
> +            }
> +        }
> +    }
> +    r0 = int128_sub(r0, m);
> +
> +    *r = r0;
> +    return int128_or(int128_lshift(q1, 64), q0);
> +}
> +
> +/*
> + * Unsigned 256-by-128 division.
> + * Returns the remainder.
> + * Returns quotient via plow and phigh.
> + * Also returns the remainder via the function return value.
> + */
> +Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor)
> +{
> +    Int128 dhi = *phigh;
> +    Int128 dlo = *plow;
> +    Int128 rem, dhighest;
> +    int sh;
> +
> +    if (!int128_nz(divisor) || !int128_nz(dhi)) {
> +        *plow  = int128_divu(dlo, divisor);
> +        *phigh = int128_zero();
> +        return int128_remu(dlo, divisor);
> +    } else {
> +        sh = clz128(divisor);
> +
> +        if (int128_ult(dhi, divisor)) {
> +            if (sh != 0) {
> +                /* normalize the divisor, shifting the dividend
> accordingly */
> +                divisor = int128_lshift(divisor, sh);
> +                dhi = int128_or(int128_lshift(dhi, sh),
> +                                int128_urshift(dlo, (128 - sh)));
> +                dlo = int128_lshift(dlo, sh);
> +            }
> +
> +            *phigh = int128_zero();
> +            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
> +        } else {
> +            if (sh != 0) {
> +                /* normalize the divisor, shifting the dividend
> accordingly */
> +                divisor = int128_lshift(divisor, sh);
> +                dhighest = int128_rshift(dhi, (128 - sh));
> +                dhi = int128_or(int128_lshift(dhi, sh),
> +                                int128_urshift(dlo, (128 - sh)));
> +                dlo = int128_lshift(dlo, sh);
> +
> +                *phigh = udiv256_qrnnd(&dhi, dhighest, dhi, divisor);
> +            } else {
> +                /*
> +                 * dhi >= divisor
> +                 * Since the MSB of divisor is set (sh == 0),
> +                 * (dhi - divisor) < divisor
> +                 *
> +                 * Thus, the high part of the quotient is 1, and we can
> +                 * calculate the low part with a single call to udiv_qrnnd
> +                 * after subtracting divisor from dhi
> +                 */
> +                dhi = int128_sub(dhi, divisor);
> +                *phigh = int128_one();
> +            }
> +
> +            *plow = udiv256_qrnnd(&rem, dhi, dlo, divisor);
> +        }
> +
> +        /*
> +         * since the dividend/divisor might have been normalized,
> +         * the remainder might also have to be shifted back
> +         */
> +        rem = int128_urshift(rem, sh);
> +        return rem;
> +    }
> +}
> +
> +/*
> + * Signed 256-by-128 division.
> + * Returns quotient via plow and phigh.
> + * Also returns the remainder via the function return value.
> + */
> +Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor)
> +{
> +    bool neg_quotient = false, neg_remainder = false;
> +    Int128 unsig_hi = *phigh, unsig_lo = *plow;
> +    Int128 rem;
> +
> +    if (!int128_nonneg(*phigh)) {
> +        neg_quotient = !neg_quotient;
> +        neg_remainder = !neg_remainder;
> +
> +        if (!int128_nz(unsig_lo)) {
> +            unsig_hi = int128_neg(unsig_hi);
> +        } else {
> +            unsig_hi = int128_not(unsig_hi);
> +            unsig_lo = int128_neg(unsig_lo);
> +        }
> +    }
> +
> +    if (!int128_nonneg(divisor)) {
> +        neg_quotient = !neg_quotient;
> +
> +        divisor = int128_neg(divisor);
> +    }
> +
> +    rem = divu256(&unsig_lo, &unsig_hi, divisor);
> +
> +    if (neg_quotient) {
> +        if (!int128_nz(unsig_lo)) {
> +            *phigh = int128_neg(unsig_hi);
> +            *plow = int128_zero();
> +        } else {
> +            *phigh = int128_not(unsig_hi);
> +            *plow = int128_neg(unsig_lo);
> +        }
> +    } else {
> +        *phigh = unsig_hi;
> +        *plow = unsig_lo;
> +    }
> +
> +    if (neg_remainder) {
> +        return int128_neg(rem);
> +    } else {
> +        return rem;
> +    }
> +}
> --
> 2.37.0.rc0
>
>
>

-- 
Marc-André Lureau