From: drh <>
Date: Thu, 19 Mar 2026 13:40:40 +0000 (+0000)
Subject: Use compiler intrinsics to improve the performance of
X-Git-Tag: major-release~71
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=915a55444b42e8a3e61f65bab015ca96cd2342d4;p=thirdparty%2Fsqlite.git

Use compiler intrinsics to improve the performance of
sqlite3Multiply160().

FossilOrigin-Name: 3c64f31392328f51e205fde52f19cf70c193e90897ccb7e93c685bad4f342cac
---

diff --git a/manifest b/manifest
index bf533f05c5..31d28c58e7 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Do\snot\sassume\sthat\sa\srecursive\sCTE\semits\srows\sin\sORDER\sBY\sorder.\sFix\sfor\sforum\spost\s[forum:deb1eadf4d677bd5\s|\sdeb1eadf4d677bd5].
-D 2026-03-19T10:51:40.690
+C Use\scompiler\sintrinsics\sto\simprove\sthe\sperformance\sof\nsqlite3Multiply160().
+D 2026-03-19T13:40:40.360
 F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@ -797,7 +797,7 @@ F src/trigger.c 4bf3bfb3851d165e4404a9f9e69357345f3f7103378c07e07139fdd8aeb7bd20
 F src/update.c 3e5e7ff66fa19ebe4d1b113d480639a24cc1175adbefabbd1a948a07f28e37cf
 F src/upsert.c 215328c3f91623c520ec8672c44323553f12caeb4f01b1090ebdca99fdf7b4f1
 F src/utf.c 7267c3fb9e2467020507601af3354c2446c61f444387e094c779dccd5ca62165
-F src/util.c 7a4ba925c70380c06279fe14414227c9e23e8797a564cee61241da7ab47cf3d0
+F src/util.c 51662502243422f3238a7220fe00de32d9a7d0d3149dd33c6d721d7039cb2e74
 F src/vacuum.c d3d35d8ae893d419ade5fa196d761a83bddcbb62137a1a157ae751ef38b26e82
 F src/vdbe.c 01e380d1847dd934f9c6c73b2bb9df68915b3f917e63244f6f02c95641ca3acb
 F src/vdbe.h 70e862ac8a11b590f8c1eaac17a0078429d42bc4ea3f757a9af0f451dd966a71
@@ -2194,9 +2194,8 @@ F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee
 F tool/warnings.sh a554d13f6e5cf3760f041b87939e3d616ec6961859c3245e8ef701d1eafc2ca2
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
 F tool/winmain.c 00c8fb88e365c9017db14c73d3c78af62194d9644feaf60e220ab0f411f3604c
-P 5c237f1f863a32cf229010d2024d0d1e76a07a4d8b9492b26503b959f1c32485 a9a0dd521c7c24b0c8b22abf2a131028f4dc9cd233678dc1f658da81a4a70e4b
-R 05ecba0cebbda621ad1348997fcbfa48
-T +closed a9a0dd521c7c24b0c8b22abf2a131028f4dc9cd233678dc1f658da81a4a70e4b
-U dan
-Z a3e30a0c8e137f9263850331b9b6cc54
+P cadb6cdd32c3c9abd7e063f25acd39dddc9ff764a16019ffd5aa11063175326f
+R 4f3af9012bcfc827e4349045b7fa7e69
+U drh
+Z 0005327f465235b9cff79f72edc88c99
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 86e308128e..785032cb26 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-cadb6cdd32c3c9abd7e063f25acd39dddc9ff764a16019ffd5aa11063175326f
+3c64f31392328f51e205fde52f19cf70c193e90897ccb7e93c685bad4f342cac
diff --git a/src/util.c b/src/util.c
index 33eea8b06a..ae6b231ad1 100644
--- a/src/util.c
+++ b/src/util.c
@@ -499,6 +499,20 @@ static u64 sqlite3Multiply128(u64 a, u64 b, u64 *pLo){
 ** The lower 64 bits of A*B are discarded.
 */
 static u64 sqlite3Multiply160(u64 a, u32 aLo, u64 b, u32 *pLo){
+#if (defined(__GNUC__) || defined(__clang__)) \
+        && (defined(__x86_64__) || defined(__aarch64__) || defined(__riscv))
+  __uint128_t r = (__uint128_t)a * b;
+  r += ((__uint128_t)aLo * b) >> 32;
+  *pLo = (r>>32)&0xffffffff;
+  return r>>64;
+#elif defined(_MSC_VER) && defined(_M_X64)
+  u64 r1_hi = __umulh(a,b);
+  u64 r1_lo = a*b;
+  u64 r2 = (__umulh((u64)aLo,b)<<32) + ((aLo*b)>>32);
+  r1_hi += _addcarry_u64(0, r1_lo, r2, &r1_lo);
+  *pLo = r1_lo>>32;
+  return r1_hi;
+#else
   u64 x2 = a>>32;
   u64 x1 = a&0xffffffff;
   u64 x0 = aLo;
@@ -520,6 +534,7 @@ static u64 sqlite3Multiply160(u64 a, u32 aLo, u64 b, u32 *pLo){
   r3 += r2>>32;
   *pLo = r2&0xffffffff;
   return (r4<<32) + r3;
+#endif
 }
 
 /*