From 0339047bc93147c1c6f78f867ae6b0c215406235 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 23 Mar 2012 17:29:57 -0400
Subject: [PATCH] Code review for protransform patches.
Fix loss of previous expression-simplification work when a transform
function fires: we must not simply revert to untransformed input tree.
Instead build a dummy FuncExpr node to pass to the transform function.
This has the additional advantage of providing a simpler, more uniform
API for transform functions.
Move documentation to a somewhat less buried spot, relocate some
poorly-placed code, be more wary of null constants and invalid typmod
values, add an opr_sanity check on protransform function signatures,
and some other minor cosmetic adjustments.
Note: although this patch touches pg_proc.h, no need for catversion
bump, because the changes are cosmetic and don't actually change the
intended catalog contents.
---
doc/src/sgml/catalogs.sgml | 3 +-
doc/src/sgml/xfunc.sgml | 34 +++++++
src/backend/nodes/nodeFuncs.c | 29 +++++-
src/backend/optimizer/util/clauses.c | 115 ++++++++++-------------
src/backend/parser/parse_clause.c | 22 -----
src/backend/utils/adt/datetime.c | 29 +++---
src/backend/utils/adt/numeric.c | 23 +++--
src/backend/utils/adt/timestamp.c | 30 +++---
src/backend/utils/adt/varbit.c | 23 +++--
src/backend/utils/adt/varchar.c | 26 ++---
src/include/catalog/pg_proc.h | 23 ++---
src/include/nodes/nodeFuncs.h | 1 +
src/include/parser/parse_clause.h | 2 -
src/test/regress/expected/opr_sanity.out | 10 ++
src/test/regress/sql/opr_sanity.sql | 7 ++
15 files changed, 205 insertions(+), 172 deletions(-)
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
index 9564e012e66..dcaeda413d3 100644
--- a/doc/src/sgml/catalogs.sgml
+++ b/doc/src/sgml/catalogs.sgml
@@ -4398,7 +4398,8 @@
<entry><structfield>protransform</structfield></entry>
<entry><type>regproc</type></entry>
<entry><literal><link linkend="catalog-pg-proc"><structname>pg_proc</structname></link>.oid</literal></entry>
- <entry>Calls to function can be simplified by this other function</entry>
+ <entry>Calls to this function can be simplified by this other function
+ (see <xref linkend="xfunc-transform-functions">)</entry>
</row>
<row>
diff --git a/doc/src/sgml/xfunc.sgml b/doc/src/sgml/xfunc.sgml
index e8620ef0738..58df90e30fe 100644
--- a/doc/src/sgml/xfunc.sgml
+++ b/doc/src/sgml/xfunc.sgml
@@ -3177,6 +3177,40 @@ CREATE FUNCTION make_array(anyelement) RETURNS anyarray
</para>
</sect2>
+ <sect2 id="xfunc-transform-functions">
+ <title>Transform Functions</title>
+
+ <para>
+ Some function calls can be simplified during planning based on
+ properties specific to the function. For example,
+ <literal>int4mul(n, 1)</> could be simplified to just <literal>n</>.
+ To define such function-specific optimizations, write a
+ <firstterm>transform function</> and place its OID in the
+ <structfield>protransform</> field of the primary function's
+ <structname>pg_proc</> entry. The transform function must have the SQL
+ signature <literal>protransform(internal) RETURNS internal</>. The
+ argument, actually <type>FuncExpr *</>, is a dummy node representing a
+ call to the primary function. If the transform function's study of the
+ expression tree proves that a simplified expression tree can substitute
+ for all possible concrete calls represented thereby, build and return
+ that simplified expression. Otherwise, return a <literal>NULL</>
+ pointer (<emphasis>not</> a SQL null).
+ </para>
+
+ <para>
+ We make no guarantee that <productname>PostgreSQL</> will never call the
+ primary function in cases that the transform function could simplify.
+ Ensure rigorous equivalence between the simplified expression and an
+ actual call to the primary function.
+ </para>
+
+ <para>
+ Currently, this facility is not exposed to users at the SQL level
+ because of security concerns, so it is only practical to use for
+ optimizing built-in functions.
+ </para>
+ </sect2>
+
<sect2>
<title>Shared Memory and LWLocks</title>
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 51459c4a43f..6f9e0536694 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -17,6 +17,7 @@
#include "catalog/pg_collation.h"
#include "catalog/pg_type.h"
#include "miscadmin.h"
+#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "nodes/relation.h"
#include "utils/builtins.h"
@@ -547,6 +548,30 @@ exprIsLengthCoercion(const Node *expr, int32 *coercedTypmod)
return false;
}
+/*
+ * relabel_to_typmod
+ * Add a RelabelType node that changes just the typmod of the expression.
+ *
+ * This is primarily intended to be used during planning. Therefore, it
+ * strips any existing RelabelType nodes to maintain the planner's invariant
+ * that there are not adjacent RelabelTypes, and it uses COERCE_DONTCARE
+ * which would typically be inappropriate earlier.
+ */
+Node *
+relabel_to_typmod(Node *expr, int32 typmod)
+{
+ Oid type = exprType(expr);
+ Oid coll = exprCollation(expr);
+
+ /* Strip any existing RelabelType node(s) */
+ while (expr && IsA(expr, RelabelType))
+ expr = (Node *) ((RelabelType *) expr)->arg;
+
+ /* Apply new typmod, preserving the previous exposed type and collation */
+ return (Node *) makeRelabelType((Expr *) expr, type, typmod, coll,
+ COERCE_DONTCARE);
+}
+
/*
* expression_returns_set
* Test whether an expression returns a set result.
@@ -2694,7 +2719,9 @@ query_or_expression_tree_mutator(Node *node,
* that could appear under it, but not other statement types.
*/
bool
- raw_expression_tree_walker(Node *node, bool (*walker) (), void *context)
+raw_expression_tree_walker(Node *node,
+ bool (*walker) (),
+ void *context)
{
ListCell *temp;
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index b14ae2e3670..117c9c0e451 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -107,11 +107,11 @@ static List *simplify_and_arguments(List *args,
eval_const_expressions_context *context,
bool *haveNull, bool *forceFalse);
static Node *simplify_boolean_equality(Oid opno, List *args);
-static Expr *simplify_function(Expr *oldexpr, Oid funcid,
- Oid result_type, int32 result_typmod, Oid result_collid,
- Oid input_collid, List **args,
+static Expr *simplify_function(Oid funcid,
+ Oid result_type, int32 result_typmod,
+ Oid result_collid, Oid input_collid, List **args,
bool has_named_args,
- bool allow_inline,
+ bool allow_non_const,
eval_const_expressions_context *context);
static List *reorder_function_arguments(List *args, Oid result_type,
HeapTuple func_tuple,
@@ -2332,8 +2332,7 @@ eval_const_expressions_mutator(Node *node,
* length coercion; we want to preserve the typmod in the
* eventual Const if so.
*/
- simple = simplify_function((Expr *) expr,
- expr->funcid,
+ simple = simplify_function(expr->funcid,
expr->funcresulttype,
exprTypmod(node),
expr->funccollid,
@@ -2389,8 +2388,7 @@ eval_const_expressions_mutator(Node *node,
* Code for op/func reduction is pretty bulky, so split it out
* as a separate function.
*/
- simple = simplify_function((Expr *) expr,
- expr->opfuncid,
+ simple = simplify_function(expr->opfuncid,
expr->opresulttype, -1,
expr->opcollid,
expr->inputcollid,
@@ -2491,8 +2489,7 @@ eval_const_expressions_mutator(Node *node,
* Code for op/func reduction is pretty bulky, so split it
* out as a separate function.
*/
- simple = simplify_function((Expr *) expr,
- expr->opfuncid,
+ simple = simplify_function(expr->opfuncid,
expr->opresulttype, -1,
expr->opcollid,
expr->inputcollid,
@@ -2698,8 +2695,7 @@ eval_const_expressions_mutator(Node *node,
getTypeInputInfo(expr->resulttype,
&infunc, &intypioparam);
- simple = simplify_function(NULL,
- outfunc,
+ simple = simplify_function(outfunc,
CSTRINGOID, -1,
InvalidOid,
InvalidOid,
@@ -2728,8 +2724,7 @@ eval_const_expressions_mutator(Node *node,
false,
true));
- simple = simplify_function(NULL,
- infunc,
+ simple = simplify_function(infunc,
expr->resulttype, -1,
expr->resultcollid,
InvalidOid,
@@ -3581,15 +3576,11 @@ simplify_boolean_equality(Oid opno, List *args)
* Subroutine for eval_const_expressions: try to simplify a function call
* (which might originally have been an operator; we don't care)
*
- * Inputs are the original expression (can be NULL), function OID, actual
- * result type OID (which is needed for polymorphic functions), result typmod,
- * result collation, the input collation to use for the function, the
- * pre-simplified argument list, and some flags; also the context data for
- * eval_const_expressions. In common cases, several of the arguments could be
- * derived from the original expression. Sending them separately avoids
- * duplicating NodeTag-specific knowledge, and it's necessary for CoerceViaIO.
- * A NULL original expression disables use of transform functions while
- * retaining all other behaviors.
+ * Inputs are the function OID, actual result type OID (which is needed for
+ * polymorphic functions), result typmod, result collation,
+ * the input collation to use for the function,
+ * the pre-simplified argument list, and some flags;
+ * also the context data for eval_const_expressions.
*
* Returns a simplified expression if successful, or NULL if cannot
* simplify the function call.
@@ -3601,28 +3592,32 @@ simplify_boolean_equality(Oid opno, List *args)
* pass-by-reference, and it may get modified even if simplification fails.
*/
static Expr *
-simplify_function(Expr *oldexpr, Oid funcid,
- Oid result_type, int32 result_typmod, Oid result_collid,
- Oid input_collid, List **args,
+simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
+ Oid result_collid, Oid input_collid, List **args,
bool has_named_args,
- bool allow_inline,
+ bool allow_non_const,
eval_const_expressions_context *context)
{
HeapTuple func_tuple;
+ Form_pg_proc func_form;
Expr *newexpr;
- Oid transform;
/*
* We have three strategies for simplification: execute the function to
* deliver a constant result, use a transform function to generate a
* substitute node tree, or expand in-line the body of the function
* definition (which only works for simple SQL-language functions, but
- * that is a common case). Each needs access to the function's pg_proc
- * tuple, so fetch it just once.
+ * that is a common case). Each case needs access to the function's
+ * pg_proc tuple, so fetch it just once.
+ *
+ * Note: the allow_non_const flag suppresses both the second and third
+ * strategies; so if !allow_non_const, simplify_function can only return
+ * a Const or NULL. Argument-list rewriting happens anyway, though.
*/
func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
if (!HeapTupleIsValid(func_tuple))
elog(ERROR, "cache lookup failed for function %u", funcid);
+ func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
/*
* While we have the tuple, reorder named arguments and add default
@@ -3631,48 +3626,38 @@ simplify_function(Expr *oldexpr, Oid funcid,
if (has_named_args)
*args = reorder_function_arguments(*args, result_type, func_tuple,
context);
- else if (((Form_pg_proc) GETSTRUCT(func_tuple))->pronargs > list_length(*args))
+ else if (func_form->pronargs > list_length(*args))
*args = add_function_defaults(*args, result_type, func_tuple, context);
newexpr = evaluate_function(funcid, result_type, result_typmod,
result_collid, input_collid, *args,
func_tuple, context);
- /*
- * Some functions calls can be simplified at plan time based on properties
- * specific to the function. For example, "varchar(s::varchar(4), 8,
- * true)" simplifies to "s::varchar(4)", and "int4mul(n, 1)" could
- * simplify to "n". To define such function-specific optimizations, write
- * a "transform function" and store its OID in the pg_proc.protransform of
- * the primary function. Give each transform function the signature
- * "protransform(internal) RETURNS internal". The argument, internally an
- * Expr *, is the node representing a call to the primary function. If
- * the transform function's study of that node proves that a simplified
- * Expr substitutes for all possible concrete calls represented thereby,
- * return that simplified Expr. Otherwise, return the NULL pointer.
- *
- * Currently, the specific Expr nodetag can be FuncExpr, OpExpr or
- * DistinctExpr. This list may change in the future. The function should
- * check the nodetag and return the NULL pointer for unexpected inputs.
- *
- * We make no guarantee that PostgreSQL will never call the primary
- * function in cases that the transform function would simplify. Ensure
- * rigorous equivalence between the simplified expression and an actual
- * call to the primary function.
- *
- * Currently, this facility is undocumented and not exposed to users at
- * the SQL level. Core length coercion casts use it to avoid calls
- * guaranteed to return their input unchanged. This in turn allows ALTER
- * TABLE ALTER TYPE to avoid rewriting tables for some typmod changes. In
- * the future, this facility may find other applications, like simplifying
- * x*0, x*1, and x+0.
- */
- transform = ((Form_pg_proc) GETSTRUCT(func_tuple))->protransform;
- if (!newexpr && OidIsValid(transform) && oldexpr)
- newexpr = (Expr *) DatumGetPointer(OidFunctionCall1(transform,
- PointerGetDatum(oldexpr)));
+ if (!newexpr && allow_non_const && OidIsValid(func_form->protransform))
+ {
+ /*
+ * Build a dummy FuncExpr node containing the simplified arg list. We
+ * use this approach to present a uniform interface to the transform
+ * function regardless of how the function is actually being invoked.
+ */
+ FuncExpr fexpr;
+
+ fexpr.xpr.type = T_FuncExpr;
+ fexpr.funcid = funcid;
+ fexpr.funcresulttype = result_type;
+ fexpr.funcretset = func_form->proretset;
+ fexpr.funcformat = COERCE_DONTCARE;
+ fexpr.funccollid = result_collid;
+ fexpr.inputcollid = input_collid;
+ fexpr.args = *args;
+ fexpr.location = -1;
+
+ newexpr = (Expr *)
+ DatumGetPointer(OidFunctionCall1(func_form->protransform,
+ PointerGetDatum(&fexpr)));
+ }
- if (!newexpr && allow_inline)
+ if (!newexpr && allow_non_const)
newexpr = inline_function(funcid, result_type, result_collid,
input_collid, *args,
func_tuple, context);
diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c
index 3a23cddd337..97ab9d5581a 100644
--- a/src/backend/parser/parse_clause.c
+++ b/src/backend/parser/parse_clause.c
@@ -2271,25 +2271,3 @@ transformFrameOffset(ParseState *pstate, int frameOptions, Node *clause)
return node;
}
-
-/*
- * relabel_to_typmod
- * Add a RelabelType node that changes just the typmod, and remove all
- * now-superfluous RelabelType nodes beneath it.
- */
-Node *
-relabel_to_typmod(Node *expr, int32 typmod)
-{
- Oid type = exprType(expr);
- Oid coll = exprCollation(expr);
-
- /*
- * Strip any existing RelabelType, then add one. This is to preserve the
- * invariant of no redundant RelabelTypes.
- */
- while (IsA(expr, RelabelType))
- expr = (Node *) ((RelabelType *) expr)->arg;
-
- return (Node *) makeRelabelType((Expr *) expr, type, typmod, coll,
- COERCE_DONTCARE);
-}
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 9ceb269b3fc..31ae045da9d 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -24,7 +24,6 @@
#include "funcapi.h"
#include "miscadmin.h"
#include "nodes/nodeFuncs.h"
-#include "parser/parse_clause.h"
#include "utils/builtins.h"
#include "utils/date.h"
#include "utils/datetime.h"
@@ -4153,32 +4152,34 @@ CheckDateTokenTables(void)
}
/*
- * Helper for temporal protransform functions. Types time, timetz, timestamp
- * and timestamptz each have a range of allowed precisions. An unspecified
- * precision is rigorously equivalent to the highest specifiable precision.
+ * Common code for temporal protransform functions. Types time, timetz,
+ * timestamp and timestamptz each have a range of allowed precisions. An
+ * unspecified precision is rigorously equivalent to the highest specifiable
+ * precision.
+ *
+ * Note: timestamp_scale throws an error when the typmod is out of range, but
+ * we can't get there from a cast: our typmodin will have caught it already.
*/
Node *
TemporalTransform(int32 max_precis, Node *node)
{
FuncExpr *expr = (FuncExpr *) node;
- Node *typmod;
Node *ret = NULL;
+ Node *typmod;
- if (!IsA(expr, FuncExpr))
- return ret;
+ Assert(IsA(expr, FuncExpr));
+ Assert(list_length(expr->args) >= 2);
- Assert(list_length(expr->args) == 2);
- typmod = lsecond(expr->args);
+ typmod = (Node *) lsecond(expr->args);
- if (IsA(typmod, Const))
+ if (IsA(typmod, Const) && !((Const *) typmod)->constisnull)
{
- Node *source = linitial(expr->args);
+ Node *source = (Node *) linitial(expr->args);
int32 old_precis = exprTypmod(source);
int32 new_precis = DatumGetInt32(((Const *) typmod)->constvalue);
- if (new_precis == -1 ||
- new_precis == max_precis ||
- (old_precis != -1 && new_precis >= old_precis))
+ if (new_precis < 0 || new_precis == max_precis ||
+ (old_precis >= 0 && new_precis >= old_precis))
ret = relabel_to_typmod(source, new_precis);
}
diff --git a/src/backend/utils/adt/numeric.c b/src/backend/utils/adt/numeric.c
index 627870a4464..5723b9af4ed 100644
--- a/src/backend/utils/adt/numeric.c
+++ b/src/backend/utils/adt/numeric.c
@@ -31,7 +31,6 @@
#include "libpq/pqformat.h"
#include "miscadmin.h"
#include "nodes/nodeFuncs.h"
-#include "parser/parse_clause.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/int8.h"
@@ -717,7 +716,7 @@ numeric_send(PG_FUNCTION_ARGS)
/*
* numeric_transform() -
*
- * Flatten calls to our length coercion function that solely represent
+ * Flatten calls to numeric's length coercion function that solely represent
* increases in allowable precision. Scale changes mutate every datum, so
* they are unoptimizable. Some values, e.g. 1E-1001, can only fit into an
* unconstrained numeric, so a change from an unconstrained numeric to any
@@ -727,18 +726,17 @@ Datum
numeric_transform(PG_FUNCTION_ARGS)
{
FuncExpr *expr = (FuncExpr *) PG_GETARG_POINTER(0);
- Node *typmod;
Node *ret = NULL;
+ Node *typmod;
- if (!IsA(expr, FuncExpr))
- PG_RETURN_POINTER(ret);
+ Assert(IsA(expr, FuncExpr));
+ Assert(list_length(expr->args) >= 2);
- Assert(list_length(expr->args) == 2);
- typmod = lsecond(expr->args);
+ typmod = (Node *) lsecond(expr->args);
- if (IsA(typmod, Const))
+ if (IsA(typmod, Const) && !((Const *) typmod)->constisnull)
{
- Node *source = linitial(expr->args);
+ Node *source = (Node *) linitial(expr->args);
int32 old_typmod = exprTypmod(source);
int32 new_typmod = DatumGetInt32(((Const *) typmod)->constvalue);
int32 old_scale = (old_typmod - VARHDRSZ) & 0xffff;
@@ -748,11 +746,12 @@ numeric_transform(PG_FUNCTION_ARGS)
/*
* If new_typmod < VARHDRSZ, the destination is unconstrained; that's
- * always OK. If old_typmod >= VARHDRSZ, the source is constrained.
- * and we're OK if the scale is unchanged and the precison is not
+ * always OK. If old_typmod >= VARHDRSZ, the source is constrained,
+ * and we're OK if the scale is unchanged and the precision is not
* decreasing. See further notes in function header comment.
*/
- if (new_typmod < VARHDRSZ || (old_typmod >= VARHDRSZ &&
+ if (new_typmod < (int32) VARHDRSZ ||
+ (old_typmod >= (int32) VARHDRSZ &&
new_scale == old_scale && new_precision >= old_precision))
ret = relabel_to_typmod(source, new_typmod);
}
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index 88ff57dd38a..9a7238be38d 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -28,7 +28,6 @@
#include "libpq/pqformat.h"
#include "miscadmin.h"
#include "nodes/nodeFuncs.h"
-#include "parser/parse_clause.h"
#include "parser/scansup.h"
#include "utils/array.h"
#include "utils/builtins.h"
@@ -316,10 +315,6 @@ timestamptypmodout(PG_FUNCTION_ARGS)
Datum
timestamp_transform(PG_FUNCTION_ARGS)
{
- /*
- * timestamp_scale throws an error when the typmod is out of range, but we
- * can't get there from a cast: our typmodin will have caught it already.
- */
PG_RETURN_POINTER(TemporalTransform(MAX_TIMESTAMP_PRECISION,
(Node *) PG_GETARG_POINTER(0)));
}
@@ -937,18 +932,17 @@ Datum
interval_transform(PG_FUNCTION_ARGS)
{
FuncExpr *expr = (FuncExpr *) PG_GETARG_POINTER(0);
- Node *typmod;
Node *ret = NULL;
+ Node *typmod;
- if (!IsA(expr, FuncExpr))
- PG_RETURN_POINTER(ret);
+ Assert(IsA(expr, FuncExpr));
+ Assert(list_length(expr->args) >= 2);
- Assert(list_length(expr->args) == 2);
- typmod = lsecond(expr->args);
+ typmod = (Node *) lsecond(expr->args);
- if (IsA(typmod, Const))
+ if (IsA(typmod, Const) && !((Const *) typmod)->constisnull)
{
- Node *source = linitial(expr->args);
+ Node *source = (Node *) linitial(expr->args);
int32 old_typmod = exprTypmod(source);
int32 new_typmod = DatumGetInt32(((Const *) typmod)->constvalue);
int old_range;
@@ -958,7 +952,7 @@ interval_transform(PG_FUNCTION_ARGS)
int new_range_fls;
int old_range_fls;
- if (old_typmod == -1)
+ if (old_typmod < 0)
{
old_range = INTERVAL_FULL_RANGE;
old_precis = INTERVAL_FULL_PRECISION;
@@ -978,11 +972,9 @@ interval_transform(PG_FUNCTION_ARGS)
*/
new_range_fls = fls(new_range);
old_range_fls = fls(old_range);
- if (new_typmod == -1 ||
- ((new_range_fls >= SECOND ||
- new_range_fls >= old_range_fls) &&
- (old_range_fls < SECOND ||
- new_precis >= MAX_INTERVAL_PRECISION ||
+ if (new_typmod < 0 ||
+ ((new_range_fls >= SECOND || new_range_fls >= old_range_fls) &&
+ (old_range_fls < SECOND || new_precis >= MAX_INTERVAL_PRECISION ||
new_precis >= old_precis)))
ret = relabel_to_typmod(source, new_typmod);
}
@@ -1068,7 +1060,7 @@ AdjustIntervalForTypmod(Interval *interval, int32 typmod)
* can't do it consistently. (We cannot enforce a range limit on the
* highest expected field, since we do not have any equivalent of
* SQL's <interval leading field precision>.) If we ever decide to
- * revisit this, interval_transform will likely requite adjusting.
+ * revisit this, interval_transform will likely require adjusting.
*
* Note: before PG 8.4 we interpreted a limited set of fields as
* actually causing a "modulo" operation on a given value, potentially
diff --git a/src/backend/utils/adt/varbit.c b/src/backend/utils/adt/varbit.c
index 1227e5a5082..e74e062338d 100644
--- a/src/backend/utils/adt/varbit.c
+++ b/src/backend/utils/adt/varbit.c
@@ -19,7 +19,6 @@
#include "access/htup.h"
#include "libpq/pqformat.h"
#include "nodes/nodeFuncs.h"
-#include "parser/parse_clause.h"
#include "utils/array.h"
#include "utils/varbit.h"
@@ -649,31 +648,31 @@ varbit_send(PG_FUNCTION_ARGS)
/*
* varbit_transform()
- * Flatten calls to our length coercion function that leave the new maximum
- * length >= the previous maximum length. We ignore the isExplicit argument,
- * which only affects truncation.
+ * Flatten calls to varbit's length coercion function that set the new maximum
+ * length >= the previous maximum length. We can ignore the isExplicit
+ * argument, since that only affects truncation cases.
*/
Datum
varbit_transform(PG_FUNCTION_ARGS)
{
FuncExpr *expr = (FuncExpr *) PG_GETARG_POINTER(0);
- Node *typmod;
Node *ret = NULL;
+ Node *typmod;
- if (!IsA(expr, FuncExpr))
- PG_RETURN_POINTER(ret);
+ Assert(IsA(expr, FuncExpr));
+ Assert(list_length(expr->args) >= 2);
- Assert(list_length(expr->args) == 3);
- typmod = lsecond(expr->args);
+ typmod = (Node *) lsecond(expr->args);
- if (IsA(typmod, Const))
+ if (IsA(typmod, Const) && !((Const *) typmod)->constisnull)
{
- Node *source = linitial(expr->args);
+ Node *source = (Node *) linitial(expr->args);
int32 new_typmod = DatumGetInt32(((Const *) typmod)->constvalue);
int32 old_max = exprTypmod(source);
int32 new_max = new_typmod;
- if (new_max <= 0 || (old_max >= 0 && old_max <= new_max))
+ /* Note: varbit() treats typmod 0 as invalid, so we do too */
+ if (new_max <= 0 || (old_max > 0 && old_max <= new_max))
ret = relabel_to_typmod(source, new_typmod);
}
diff --git a/src/backend/utils/adt/varchar.c b/src/backend/utils/adt/varchar.c
index 98ec04ef631..5774102bc02 100644
--- a/src/backend/utils/adt/varchar.c
+++ b/src/backend/utils/adt/varchar.c
@@ -19,7 +19,6 @@
#include "access/tuptoaster.h"
#include "libpq/pqformat.h"
#include "nodes/nodeFuncs.h"
-#include "parser/parse_clause.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "mb/pg_wchar.h"
@@ -551,31 +550,32 @@ varcharsend(PG_FUNCTION_ARGS)
/*
- * Flatten calls to our length coercion function that leave the new maximum
- * length >= the previous maximum length. We ignore the isExplicit argument,
- * which only affects truncation.
+ * varchar_transform()
+ * Flatten calls to varchar's length coercion function that set the new maximum
+ * length >= the previous maximum length. We can ignore the isExplicit
+ * argument, since that only affects truncation cases.
*/
Datum
varchar_transform(PG_FUNCTION_ARGS)
{
FuncExpr *expr = (FuncExpr *) PG_GETARG_POINTER(0);
- Node *typmod;
Node *ret = NULL;
+ Node *typmod;
- if (!IsA(expr, FuncExpr))
- PG_RETURN_POINTER(ret);
+ Assert(IsA(expr, FuncExpr));
+ Assert(list_length(expr->args) >= 2);
- Assert(list_length(expr->args) == 3);
- typmod = lsecond(expr->args);
+ typmod = (Node *) lsecond(expr->args);
- if (IsA(typmod, Const))
+ if (IsA(typmod, Const) && !((Const *) typmod)->constisnull)
{
- Node *source = linitial(expr->args);
+ Node *source = (Node *) linitial(expr->args);
+ int32 old_typmod = exprTypmod(source);
int32 new_typmod = DatumGetInt32(((Const *) typmod)->constvalue);
- int32 old_max = exprTypmod(source) - VARHDRSZ;
+ int32 old_max = old_typmod - VARHDRSZ;
int32 new_max = new_typmod - VARHDRSZ;
- if (new_max < 0 || (old_max >= 0 && old_max <= new_max))
+ if (new_typmod < 0 || (old_typmod >= 0 && old_max <= new_max))
ret = relabel_to_typmod(source, new_typmod);
}
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 2db848903c4..49b0754a2ca 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -767,7 +767,7 @@ DATA(insert OID = 668 ( bpchar PGNSP PGUID 12 1 0 0 0 f f f f t f i 3 0 10
DESCR("adjust char() to typmod length");
DATA(insert OID = 3097 ( varchar_transform PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2281 "2281" _null_ _null_ _null_ _null_ varchar_transform _null_ _null_ _null_ ));
DESCR("transform a varchar length coercion");
-DATA(insert OID = 669 ( varchar PGNSP PGUID 12 1 0 0 3097 f f f f t f i 3 0 1043 "1043 23 16" _null_ _null_ _null_ _null_ varchar _null_ _null_ _null_ ));
+DATA(insert OID = 669 ( varchar PGNSP PGUID 12 1 0 0 varchar_transform f f f f t f i 3 0 1043 "1043 23 16" _null_ _null_ _null_ _null_ varchar _null_ _null_ _null_ ));
DESCR("adjust varchar() to typmod length");
DATA(insert OID = 676 ( mktinterval PGNSP PGUID 12 1 0 0 0 f f f f t f i 2 0 704 "702 702" _null_ _null_ _null_ _null_ mktinterval _null_ _null_ _null_ ));
@@ -1267,7 +1267,7 @@ DESCR("date difference preserving months and years");
DATA(insert OID = 3918 ( interval_transform PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2281 "2281" _null_ _null_ _null_ _null_ interval_transform _null_ _null_ _null_ ));
DESCR("transform an interval length coercion");
-DATA(insert OID = 1200 ( interval PGNSP PGUID 12 1 0 0 3918 f f f f t f i 2 0 1186 "1186 23" _null_ _null_ _null_ _null_ interval_scale _null_ _null_ _null_ ));
+DATA(insert OID = 1200 ( interval PGNSP PGUID 12 1 0 0 interval_transform f f f f t f i 2 0 1186 "1186 23" _null_ _null_ _null_ _null_ interval_scale _null_ _null_ _null_ ));
DESCR("adjust interval precision");
DATA(insert OID = 1215 ( obj_description PGNSP PGUID 14 100 0 0 0 f f f f t f s 2 0 25 "26 19" _null_ _null_ _null_ _null_ "select description from pg_catalog.pg_description where objoid = $1 and classoid = (select oid from pg_catalog.pg_class where relname = $2 and relnamespace = PGNSP) and objsubid = 0" _null_ _null_ _null_ ));
@@ -2023,7 +2023,7 @@ DATA(insert OID = 1685 ( bit PGNSP PGUID 12 1 0 0 0 f f f f t f i 3 0 1560
DESCR("adjust bit() to typmod length");
DATA(insert OID = 3158 ( varbit_transform PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2281 "2281" _null_ _null_ _null_ _null_ varbit_transform _null_ _null_ _null_ ));
DESCR("transform a varbit length coercion");
-DATA(insert OID = 1687 ( varbit PGNSP PGUID 12 1 0 0 3158 f f f f t f i 3 0 1562 "1562 23 16" _null_ _null_ _null_ _null_ varbit _null_ _null_ _null_ ));
+DATA(insert OID = 1687 ( varbit PGNSP PGUID 12 1 0 0 varbit_transform f f f f t f i 3 0 1562 "1562 23 16" _null_ _null_ _null_ _null_ varbit _null_ _null_ _null_ ));
DESCR("adjust varbit() to typmod length");
DATA(insert OID = 1698 ( position PGNSP PGUID 12 1 0 0 0 f f f f t f i 2 0 23 "1560 1560" _null_ _null_ _null_ _null_ bitposition _null_ _null_ _null_ ));
@@ -2156,10 +2156,10 @@ DATA(insert OID = 2917 ( numerictypmodin PGNSP PGUID 12 1 0 0 0 f f f f t f i
DESCR("I/O typmod");
DATA(insert OID = 2918 ( numerictypmodout PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "23" _null_ _null_ _null_ _null_ numerictypmodout _null_ _null_ _null_ ));
DESCR("I/O typmod");
-DATA(insert OID = 1703 ( numeric PGNSP PGUID 12 1 0 0 3157 f f f f t f i 2 0 1700 "1700 23" _null_ _null_ _null_ _null_ numeric _null_ _null_ _null_ ));
-DESCR("adjust numeric to typmod precision/scale");
DATA(insert OID = 3157 ( numeric_transform PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2281 "2281" _null_ _null_ _null_ _null_ numeric_transform _null_ _null_ _null_ ));
DESCR("transform a numeric length coercion");
+DATA(insert OID = 1703 ( numeric PGNSP PGUID 12 1 0 0 numeric_transform f f f f t f i 2 0 1700 "1700 23" _null_ _null_ _null_ _null_ numeric _null_ _null_ _null_ ));
+DESCR("adjust numeric to typmod precision/scale");
DATA(insert OID = 1704 ( numeric_abs PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 1700 "1700" _null_ _null_ _null_ _null_ numeric_abs _null_ _null_ _null_ ));
DATA(insert OID = 1705 ( abs PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 1700 "1700" _null_ _null_ _null_ _null_ numeric_abs _null_ _null_ _null_ ));
DESCR("absolute value");
@@ -2746,7 +2746,10 @@ DESCR("less-equal-greater");
DATA(insert OID = 3917 ( timestamp_transform PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2281 "2281" _null_ _null_ _null_ _null_ timestamp_transform _null_ _null_ _null_ ));
DESCR("transform a timestamp length coercion");
-DATA(insert OID = 1961 ( timestamp PGNSP PGUID 12 1 0 0 3917 f f f f t f i 2 0 1114 "1114 23" _null_ _null_ _null_ _null_ timestamp_scale _null_ _null_ _null_ ));
+DATA(insert OID = 3944 ( time_transform PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2281 "2281" _null_ _null_ _null_ _null_ time_transform _null_ _null_ _null_ ));
+DESCR("transform a time length coercion");
+
+DATA(insert OID = 1961 ( timestamp PGNSP PGUID 12 1 0 0 timestamp_transform f f f f t f i 2 0 1114 "1114 23" _null_ _null_ _null_ _null_ timestamp_scale _null_ _null_ _null_ ));
DESCR("adjust timestamp precision");
DATA(insert OID = 1965 ( oidlarger PGNSP PGUID 12 1 0 0 0 f f f f t f i 2 0 26 "26 26" _null_ _null_ _null_ _null_ oidlarger _null_ _null_ _null_ ));
@@ -2754,13 +2757,11 @@ DESCR("larger of two");
DATA(insert OID = 1966 ( oidsmaller PGNSP PGUID 12 1 0 0 0 f f f f t f i 2 0 26 "26 26" _null_ _null_ _null_ _null_ oidsmaller _null_ _null_ _null_ ));
DESCR("smaller of two");
-DATA(insert OID = 1967 ( timestamptz PGNSP PGUID 12 1 0 0 3917 f f f f t f i 2 0 1184 "1184 23" _null_ _null_ _null_ _null_ timestamptz_scale _null_ _null_ _null_ ));
+DATA(insert OID = 1967 ( timestamptz PGNSP PGUID 12 1 0 0 timestamp_transform f f f f t f i 2 0 1184 "1184 23" _null_ _null_ _null_ _null_ timestamptz_scale _null_ _null_ _null_ ));
DESCR("adjust timestamptz precision");
-DATA(insert OID = 3944 ( time_transform PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2281 "2281" _null_ _null_ _null_ _null_ time_transform _null_ _null_ _null_ ));
-DESCR("transform a time length coercion");
-DATA(insert OID = 1968 ( time PGNSP PGUID 12 1 0 0 3944 f f f f t f i 2 0 1083 "1083 23" _null_ _null_ _null_ _null_ time_scale _null_ _null_ _null_ ));
+DATA(insert OID = 1968 ( time PGNSP PGUID 12 1 0 0 time_transform f f f f t f i 2 0 1083 "1083 23" _null_ _null_ _null_ _null_ time_scale _null_ _null_ _null_ ));
DESCR("adjust time precision");
-DATA(insert OID = 1969 ( timetz PGNSP PGUID 12 1 0 0 3944 f f f f t f i 2 0 1266 "1266 23" _null_ _null_ _null_ _null_ timetz_scale _null_ _null_ _null_ ));
+DATA(insert OID = 1969 ( timetz PGNSP PGUID 12 1 0 0 time_transform f f f f t f i 2 0 1266 "1266 23" _null_ _null_ _null_ _null_ timetz_scale _null_ _null_ _null_ ));
DESCR("adjust time with time zone precision");
DATA(insert OID = 2003 ( textanycat PGNSP PGUID 14 1 0 0 0 f f f f t f s 2 0 25 "25 2776" _null_ _null_ _null_ _null_ "select $1 || $2::pg_catalog.text" _null_ _null_ _null_ ));
diff --git a/src/include/nodes/nodeFuncs.h b/src/include/nodes/nodeFuncs.h
index def4f313ab7..e609e4bae20 100644
--- a/src/include/nodes/nodeFuncs.h
+++ b/src/include/nodes/nodeFuncs.h
@@ -29,6 +29,7 @@
extern Oid exprType(const Node *expr);
extern int32 exprTypmod(const Node *expr);
extern bool exprIsLengthCoercion(const Node *expr, int32 *coercedTypmod);
+extern Node *relabel_to_typmod(Node *expr, int32 typmod);
extern bool expression_returns_set(Node *clause);
extern Oid exprCollation(const Node *expr);
diff --git a/src/include/parser/parse_clause.h b/src/include/parser/parse_clause.h
index f8eb41aad45..fd3fc8f5709 100644
--- a/src/include/parser/parse_clause.h
+++ b/src/include/parser/parse_clause.h
@@ -44,6 +44,4 @@ extern List *transformDistinctOnClause(ParseState *pstate, List *distinctlist,
extern Index assignSortGroupRef(TargetEntry *tle, List *tlist);
extern bool targetIsInSortList(TargetEntry *tle, Oid sortop, List *sortList);
-extern Node *relabel_to_typmod(Node *expr, int32 typmod);
-
#endif /* PARSE_CLAUSE_H */
diff --git a/src/test/regress/expected/opr_sanity.out b/src/test/regress/expected/opr_sanity.out
index 7815b0d7be4..110ea4111f9 100644
--- a/src/test/regress/expected/opr_sanity.out
+++ b/src/test/regress/expected/opr_sanity.out
@@ -330,6 +330,16 @@ WHERE proargmodes IS NOT NULL AND proargnames IS NOT NULL AND
-----+---------
(0 rows)
+-- Check for protransform functions with the wrong signature
+SELECT p1.oid, p1.proname, p2.oid, p2.proname
+FROM pg_proc AS p1, pg_proc AS p2
+WHERE p2.oid = p1.protransform AND
+ (p2.prorettype != 'internal'::regtype OR p2.proretset OR p2.pronargs != 1
+ OR p2.proargtypes[0] != 'internal'::regtype);
+ oid | proname | oid | proname
+-----+---------+-----+---------
+(0 rows)
+
-- Insist that all built-in pg_proc entries have descriptions
SELECT p1.oid, p1.proname
FROM pg_proc as p1 LEFT JOIN pg_description as d
diff --git a/src/test/regress/sql/opr_sanity.sql b/src/test/regress/sql/opr_sanity.sql
index 3ed6366bfc0..a3be0c1114f 100644
--- a/src/test/regress/sql/opr_sanity.sql
+++ b/src/test/regress/sql/opr_sanity.sql
@@ -256,6 +256,13 @@ FROM pg_proc as p1
WHERE proargmodes IS NOT NULL AND proargnames IS NOT NULL AND
array_length(proargmodes,1) <> array_length(proargnames,1);
+-- Check for protransform functions with the wrong signature
+SELECT p1.oid, p1.proname, p2.oid, p2.proname
+FROM pg_proc AS p1, pg_proc AS p2
+WHERE p2.oid = p1.protransform AND
+ (p2.prorettype != 'internal'::regtype OR p2.proretset OR p2.pronargs != 1
+ OR p2.proargtypes[0] != 'internal'::regtype);
+
-- Insist that all built-in pg_proc entries have descriptions
SELECT p1.oid, p1.proname
FROM pg_proc as p1 LEFT JOIN pg_description as d
--
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