diff options
Diffstat (limited to 'ext/misc/series.c')
| -rw-r--r-- | ext/misc/series.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/ext/misc/series.c b/ext/misc/series.c index abd6af7ad..3e859a8f2 100644 --- a/ext/misc/series.c +++ b/ext/misc/series.c @@ -103,16 +103,20 @@ SQLITE_EXTENSION_INIT1 ** index is ix. The 0th member is given by smBase. The sequence members ** progress per ix increment by smStep. */ -static sqlite3_int64 genSeqMember(sqlite3_int64 smBase, - sqlite3_int64 smStep, - sqlite3_uint64 ix){ - if( ix>=(sqlite3_uint64)LLONG_MAX ){ +static sqlite3_int64 genSeqMember( + sqlite3_int64 smBase, + sqlite3_int64 smStep, + sqlite3_uint64 ix +){ + static const sqlite3_uint64 mxI64 = + ((sqlite3_uint64)0x7fffffff)<<32 | 0xffffffff; + if( ix>=mxI64 ){ /* Get ix into signed i64 range. */ - ix -= (sqlite3_uint64)LLONG_MAX; + ix -= mxI64; /* With 2's complement ALU, this next can be 1 step, but is split into * 2 for UBSAN's satisfaction (and hypothetical 1's complement ALUs.) */ - smBase += (LLONG_MAX/2) * smStep; - smBase += (LLONG_MAX - LLONG_MAX/2) * smStep; + smBase += (mxI64/2) * smStep; + smBase += (mxI64 - mxI64/2) * smStep; } /* Under UBSAN (or on 1's complement machines), must do this last term * in steps to avoid the dreaded (and harmless) signed multiply overlow. */ |