Fix SELECT -9223372036854775808 result differs from SQLite

[krishvishal]

Closes #812

-9223372036854775808 is MIN_INT64. So when we extract out the minus and try to parse the remainder it becomes greater than MAX_INT64 (9223372036854775807) and will trigger overflow, which converts the literal into Real. So we have to handle it as a special case.

[krishvishal]

Before this fix:

SQLite query plan:

addr  opcode         p1    p2    p3    p4             p5  comment             
----  -------------  ----  ----  ----  -------------  --  -------------       
0     Init           0     1     0                    0                       
1     Int64          0     1     0     -9223372036854775808  0
2     ResultRow      1     1     0                    0                       
3     Halt           0     0     0                    0                       

Limbo query plan:

limbo> EXPLAIN SELECT -9223372036854775808;
addr  opcode             p1    p2    p3    p4             p5  comment
----  -----------------  ----  ----  ----  -------------  --  -------
0     Init               0     4     0                    0   Start at 4
1     Real               0     1     0     -9.223372036854776e18  0   r[1]=-9223372036854776000
2     ResultRow          1     1     0                    0   output=r[1]
3     Halt               0     0     0                    0
4     Transaction        0     0     0                    0
5     Goto               0     1     0                    0

After this fix:

Limbo query plan:

limbo> EXPLAIN SELECT -9223372036854775808;
addr  opcode             p1    p2    p3    p4             p5  comment
----  -----------------  ----  ----  ----  -------------  --  -------
0     Init               0     4     0                    0   Start at 4
1     Integer            0     1     0                    0   r[1]=-9223372036854775808
2     ResultRow          1     1     0                    0   output=r[1]
3     Halt               0     0     0                    0   
4     Transaction        0     0     0                    0   
5     Goto               0     1     0                    0   

[seonWKim]

LGTM 👍 Thanks for the quick fix