Repair brain fade in commit b181a91981203f6ec9403115a2917bd3f9473707.

The split between which things need to happen in the C-locale case and
which needed to happen in the locale-aware case was a few bricks short
of a load.  Try to fix that.

diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index f26a77cf2936c413e87398614c3939b195d5313e..c79b6413916ce1630250db6658f0d03c90c7ea20 100644 (file)
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -1998,12 +1998,12 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
 {
    TextSortSupport    *tss = (TextSortSupport *) ssup->ssup_extra;
    text               *authoritative = DatumGetTextPP(original);
+   char               *authoritative_data = VARDATA_ANY(authoritative);
 
    /* working state */
    Datum               res;
    char               *pres;
    int                 len;
-   Size                bsize;
    uint32              hash;
 
    /*
@@ -2017,14 +2017,16 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
 
    /*
     * If we're using the C collation, use memcmp(), rather than strxfrm(),
-    * to abbreviated keys.  The full comparator for the C locale is always
+    * to abbreviate keys.  The full comparator for the C locale is always
     * memcmp(), and we can't risk having this give a different answer.
     * Besides, this should be faster, too.
     */
    if (tss->collate_c)
-       memcpy(pres, VARDATA_ANY(authoritative), Min(len, sizeof(Datum)));
+       memcpy(pres, authoritative_data, Min(len, sizeof(Datum)));
    else
    {
+       Size            bsize;
+
        /*
         * We're not using the C collation, so fall back on strxfrm.
         */
@@ -2067,6 +2069,14 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
                               Min(tss->buflen2 * 2, MaxAllocSize));
            tss->buf2 = palloc(tss->buflen2);
        }
+
+       /*
+        * Every Datum byte is always compared.  This is safe because the
+        * strxfrm() blob is itself NUL terminated, leaving no danger of
+        * misinterpreting any NUL bytes not intended to be interpreted as
+        * logically representing termination.
+        */
+       memcpy(pres, tss->buf2, Min(sizeof(Datum), bsize));
    }
 
    /*
@@ -2080,15 +2090,14 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
     * in order to compensate for cases where differences are past
     * CACHE_LINE_SIZE bytes, so as to limit the overhead of hashing.
     */
-   hash = hash_any((unsigned char *) tss->buf1, Min(len, PG_CACHE_LINE_SIZE));
+   hash = hash_any((unsigned char *) authoritative_data,
+                   Min(len, PG_CACHE_LINE_SIZE));
 
    if (len > PG_CACHE_LINE_SIZE)
        hash ^= DatumGetUInt32(hash_uint32((uint32) len));
 
    addHyperLogLog(&tss->full_card, hash);
 
-   memcpy(pres, tss->buf2, Min(sizeof(Datum), bsize));
-
    /* Hash abbreviated key */
 #if SIZEOF_DATUM == 8
    {
@@ -2105,12 +2114,6 @@ bttext_abbrev_convert(Datum original, SortSupport ssup)
 
    addHyperLogLog(&tss->abbr_card, hash);
 
-   /*
-    * Every Datum byte is always compared.  This is safe because the strxfrm()
-    * blob is itself NUL terminated, leaving no danger of misinterpreting any
-    * NUL bytes not intended to be interpreted as logically representing
-    * termination.
-    */
    return res;
 }