diff options
| author | Andres Freund <andres@anarazel.de> | 2017-12-12 16:32:31 -0800 |
|---|---|---|
| committer | Andres Freund <andres@anarazel.de> | 2017-12-12 16:55:37 -0800 |
| commit | 101c7ee3ee847bac970c74b73b4f2858484383e5 (patch) | |
| tree | 0e2c14000aa86975fbb36fb36470f54251b83b54 /src/backend/utils/adt/varlena.c | |
| parent | 4d6ad31257adaf8a51e1c4377d96afa656d9165f (diff) | |
| download | postgresql-101c7ee3ee847bac970c74b73b4f2858484383e5.tar.gz postgresql-101c7ee3ee847bac970c74b73b4f2858484383e5.zip | |
Use new overflow aware integer operations.
A previous commit added inline functions that provide fast(er) and
correct overflow checks for signed integer math. Use them in a
significant portion of backend code. There's more to touch in both
backend and frontend code, but these were the easily identifiable
cases.
The old overflow checks are noticeable in integer heavy workloads.
A secondary benefit is that getting rid of overflow checks that rely
on signed integer overflow wrapping around, will allow us to get rid
of -fwrapv in the future. Which in turn slows down other code.
Author: Andres Freund
Discussion: https://postgr.es/m/20171024103954.ztmatprlglz3rwke@alap3.anarazel.de
Diffstat (limited to 'src/backend/utils/adt/varlena.c')
| -rw-r--r-- | src/backend/utils/adt/varlena.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c index 39b68dbc651..a84e845ad24 100644 --- a/src/backend/utils/adt/varlena.c +++ b/src/backend/utils/adt/varlena.c @@ -21,6 +21,7 @@ #include "access/tuptoaster.h" #include "catalog/pg_collation.h" #include "catalog/pg_type.h" +#include "common/int.h" #include "common/md5.h" #include "lib/hyperloglog.h" #include "libpq/pqformat.h" @@ -1047,8 +1048,7 @@ text_overlay(text *t1, text *t2, int sp, int sl) ereport(ERROR, (errcode(ERRCODE_SUBSTRING_ERROR), errmsg("negative substring length not allowed"))); - sp_pl_sl = sp + sl; - if (sp_pl_sl <= sl) + if (pg_add_s32_overflow(sp, sl, &sp_pl_sl)) ereport(ERROR, (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), errmsg("integer out of range"))); @@ -2950,8 +2950,7 @@ bytea_overlay(bytea *t1, bytea *t2, int sp, int sl) ereport(ERROR, (errcode(ERRCODE_SUBSTRING_ERROR), errmsg("negative substring length not allowed"))); - sp_pl_sl = sp + sl; - if (sp_pl_sl <= sl) + if (pg_add_s32_overflow(sp, sl, &sp_pl_sl)) ereport(ERROR, (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), errmsg("integer out of range"))); @@ -5279,13 +5278,13 @@ text_format_parse_digits(const char **ptr, const char *end_ptr, int *value) while (*cp >= '0' && *cp <= '9') { - int newval = val * 10 + (*cp - '0'); + int8 digit = (*cp - '0'); - if (newval / 10 != val) /* overflow? */ + if (unlikely(pg_mul_s32_overflow(val, 10, &val)) || + unlikely(pg_add_s32_overflow(val, digit, &val))) ereport(ERROR, (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE), errmsg("number is out of range"))); - val = newval; ADVANCE_PARSE_POINTER(cp, end_ptr); found = true; } |