Add ANTLR parse tree caching with version validation

Add cross-session ANTLR parse tree caching for T-SQL stored procedures.
Serialized parse trees and datums are stored in babelfish_function_ext
using nodeToString/stringToNode. On procedure execution, cached results
are restored to skip ANTLR re-parsing. Cache reads validate the stored
bbf_version and modify_date before deserializing, skipping stale entries
from different Babelfish versions or procedures modified with the GUC
disabled.

Changes:
- Add antlr_parse_tree_text, antlr_parse_tree_datums,
  antlr_parse_tree_modify_date, and antlr_parse_tree_bbf_version columns
to sys.babelfish_function_ext
- Store serialized parse tree and version in
  pltsql_store_func_default_positions
- Restore and validate cached parse tree in new function
  pltsql_restore_func_parse_result invoked prior to ANTLR parse

Task: BABEL-6037
Signed-off-by: Manisha Deshpande <mmdeshp@amazon.com>

Author: manisha-deshpande

contrib/babelfishpg_tsql/Makefile

@@ -21,8 +21,6 @@ MODULE_big = $(EXTENSION)
 OBJS = src/pl_gram.o src/pl_handler.o src/pl_comp.o src/pl_exec.o
 OBJS += src/pl_funcs.o src/pl_scanner.o $(WIN32RES)
 OBJS += src/pl_comp-2.o
-OBJS += src/pltsql_serialize.o
-OBJS += src/pltsql_deserialize.o
 OBJS += src/pl_explain.o
 OBJS += src/properties.o
 OBJS += src/databasepropertyex.o

contrib/babelfishpg_tsql/sql/ownership.sql

@@ -41,7 +41,10 @@ CREATE TABLE sys.babelfish_function_ext (
 	create_date SYS.DATETIME NOT NULL,
 	modify_date SYS.DATETIME NOT NULL,
 	definition sys.NTEXT DEFAULT NULL,
-	antlr_parse_tree JSONB DEFAULT NULL, -- JSONB serialized ANTLR parse tree for caching
+	antlr_parse_tree_text TEXT DEFAULT NULL, -- Native PG nodeToString() serialized parse tree [TODO: convert to BINARY TEXT]
+	antlr_parse_tree_datums TEXT DEFAULT NULL, -- Native PG nodeToString() serialized datums array [TODO: convert to BINARY TEXT]
+  antlr_parse_tree_modify_date SYS.DATETIME DEFAULT NULL,
+	antlr_parse_tree_bbf_version TEXT DEFAULT NULL,
 	PRIMARY KEY(funcname, nspname, funcsignature)
 );
 GRANT SELECT ON sys.babelfish_function_ext TO PUBLIC;

contrib/babelfishpg_tsql/sql/upgrades/babelfishpg_tsql--5.5.0--5.6.0.sql

@@ -245,7 +245,10 @@ CREATE TABLE sys.babelfish_function_ext (
  create_date SYS.DATETIME NOT NULL,
  modify_date SYS.DATETIME NOT NULL,
  definition sys.NTEXT DEFAULT NULL,
- antlr_parse_tree JSONB DEFAULT NULL, -- JSONB serialized ANTLR parse tree for caching
+ antlr_parse_tree_text TEXT DEFAULT NULL, -- Native PG nodeToString() serialized parse tree
+ antlr_parse_tree_datums TEXT DEFAULT NULL, -- Native PG nodeToString() serialized datums array
+ antlr_parse_tree_modify_date SYS.DATETIME DEFAULT NULL,
+ antlr_parse_tree_bbf_version TEXT DEFAULT NULL,
  PRIMARY KEY(funcname, nspname, funcsignature)
 );
 GRANT SELECT ON sys.babelfish_function_ext TO PUBLIC;

contrib/babelfishpg_tsql/src/catalog.h

@@ -277,8 +277,11 @@ typedef FormData_bbf_servers_def *Form_bbf_servers_def;
 #define Anum_bbf_function_ext_create_date 8
 #define Anum_bbf_function_ext_modify_date 9
 #define Anum_bbf_function_ext_definition 10
-#define Anum_bbf_function_ext_antlr_parse_tree 11
-#define BBF_FUNCTION_EXT_NUM_COLS 11
+#define Anum_bbf_function_ext_antlr_parse_tree_text 11
+#define Anum_bbf_function_ext_antlr_parse_tree_datums 12
+#define Anum_bbf_function_ext_antlr_parse_tree_modify_date 13
+#define Anum_bbf_function_ext_antlr_parse_tree_bbf_version 14
+#define BBF_FUNCTION_EXT_NUM_COLS 14
 #define FLAG_IS_ANSI_NULLS_ON (1<<0)
 #define FLAG_USES_QUOTED_IDENTIFIER (1<<1)
 #define FLAG_CREATED_WITH_RECOMPILE (1<<2)

contrib/babelfishpg_tsql/src/codegen.c

@@ -147,7 +147,7 @@ create_goto(int lineno)
 {
 	PLtsql_stmt_goto *stmt_goto;
 
-	stmt_goto = palloc(sizeof(PLtsql_stmt_goto));
+	stmt_goto = makeNode(PLtsql_stmt_goto);
 	stmt_goto->cmd_type = PLTSQL_STMT_GOTO;
 	stmt_goto->lineno = lineno;
 	stmt_goto->cond = NULL;		/* unconditional goto */
@@ -159,7 +159,7 @@ create_goto(int lineno)
 static PLtsql_stmt_save_ctx *
 create_save_ctx(int lineno)
 {
-	PLtsql_stmt_save_ctx *save_ctx = palloc(sizeof(PLtsql_stmt_save_ctx));
+	PLtsql_stmt_save_ctx *save_ctx = makeNode(PLtsql_stmt_save_ctx);
 
 	save_ctx->cmd_type = PLTSQL_STMT_SAVE_CTX;
 	save_ctx->lineno = lineno;
@@ -171,7 +171,7 @@ create_save_ctx(int lineno)
 static PLtsql_stmt_restore_ctx_full *
 create_restore_ctx_full(int lineno)
 {
-	PLtsql_stmt_restore_ctx_full *restore_ctx = palloc(sizeof(PLtsql_stmt_restore_ctx_full));
+	PLtsql_stmt_restore_ctx_full *restore_ctx = makeNode(PLtsql_stmt_restore_ctx_full);
 
 	restore_ctx->cmd_type = PLTSQL_STMT_RESTORE_CTX_FULL;
 	restore_ctx->lineno = lineno;
@@ -181,7 +181,7 @@ create_restore_ctx_full(int lineno)
 static PLtsql_stmt_restore_ctx_partial *
 create_restore_ctx_partial(int lineno)
 {
-	PLtsql_stmt_restore_ctx_partial *restore_ctx = palloc(sizeof(PLtsql_stmt_restore_ctx_partial));
+	PLtsql_stmt_restore_ctx_partial *restore_ctx = makeNode(PLtsql_stmt_restore_ctx_partial);
 
 	restore_ctx->cmd_type = PLTSQL_STMT_RESTORE_CTX_PARTIAL;
 	restore_ctx->lineno = lineno;