To reduce diff vs upstream.

This was accidentally duplicated in some earlier merge or backport. It's
in an "#ifdef WIN32" block, so it's dead for GPDB, but let's be tidy.

It was used by file replication, but now it's gone.

Convert elog() calls to ereport() for user facing errors in setting
GUC values.

As of the merge with PostgreSQL 8.4, we now have builtin support for
enum GUCs. Convert the bespoke GPDB code for managing enum GUCs into
using the enum GUC functionality. There should be no user visible
changes from this except that the error messages are changing.

gp_hashagg_respill_bias has been dead for close to 10 years while
gp_hashjoin_bloomfilter was a leftover from 1fd4d7ee.
gp_hashagg_rewrite_limit was deprecated close to 10 years ago and
made into a no-op.

gp_fault_action and the consumers of gp_backup_directIO* GUCs were
removed with the recent filespaces removal.

When build remap info for fields of type described by given
tupledesc, set tupledesc in remapper only when remapping
is required.

This patch removes codegen wholesale from Greenplum.

In addition to reverting the commits involving codegen, we also removed
miscellaneous references to the feature and GUC.

The following commits from 5.0.0 were reverted (topologically ordered):

f38c9064 Support avg aggregate function in codegen
87dcae4c Capture and print error messages from llvm::verifyFunction
65137540 libgpcodegen assert() overrides use GPDB Assert()
81d378b4 GenerateExecVariableList calls regular slot_getattr when the code generation of the latter fails
05a28211 Update Google Test source path used by codegen
22a35fcc Call ereport when code generating float operators
79517271 Support overflow checks for doubles.
b5373a1e Fix codegen unittest link problem
7a1a98c9 Print filename and lineno in codegened CreateElog
58eda293 Fix wrong virtual tuple check in codegened slot_getattr
bc6faa08 Set llvm_isNull_ptr to false when the result of codegened expression evaluation is not null
8bbbd63f Enhance codegened advance_aggregates with support for null attributes
e1fd6072 Abort code generation of expression evaluation trees with unsupported ExprState types
509460ee Support null attributes in codegen expression evaluation framework
739d978d Move enrollment of codegened ExecVariableList to ExecInitNode
c05528d1 Fix CHECK_SYMBOL_DEFINED macro in CMakeLists.txt
12cfd7bd Support offset calculation when there is null in the tuple and codegen is enabled
40a2631e Use slot_getattr wrapper function for regular version.(#1194)
613e9fbb Revert "Fix codegen issue by moving slot_getattr to heaptuple.c similar to"
ee03f799 Fix cpplint error on advance aggregate
2a65b0aa Fix slot function nullptr issue in expr eval.
3107fc0e Fix for !(expr1 & expr2) and hasnull logic in slot_getatrr codegen.
c940c7f6 Fix codegen issue by moving slot_getattr to heaptuple.c similar to Postgres.
c8125736 Introduce guc to enable/disable all generator.
a4f39507 Ensure that codegen unittests pass with GCC 6.2.0 (#1177)
682d0b28 Allow overriding assert() functionality in libgpcodegen in DEBUG mode
3209258a Organize codegen source files and unit tests
d2ba88a9 Fix codegen unittests using DatumCastGenerator
020b71a5 Generate code for COUNT aggregate function
0eeec886 Fixing codegen related bugs in InitializeSupportedFunction
41055352 Rewrite PGGenericFuncGenerator to support variable number of types
e5318b6b Add AdvanceAggregatesCodegenEnroll mock function
87521715 Codegen advance_aggregates for SUM transition function
2043d95b Use string messages in codegened slot_getattr fallback block
f160fa5a Add new GUC to control Codegen Optimization level.
697ffc1a Fix cpplint errors
c5e3aed4 Support Virtual Tuples and Memtuples in SlotGetAttrCodegen
5996aaa7 Keep a reference to the CodegenManager in code generators
6833b3c2 Remove unused header and just include what you use in codegen
ab1eda87 Allow setting codegen guc to ON only if code generation is supported by the build
dcd40712 Use PGFuncGeneratorInfo to codegen pg functions
83869d1c Replace dynamic_cast with dyn_cast for llvm objects
23007017 Decide what to generate for ExecEvalExpr based on PlanState
387d8ce8 Add EXPLAIN CODEGEN to print generated IR to the client
c4a9bd27 Introduce Datum to cpp cast, cpp type to Datum cast  and normal cast.(#944)
66158dfd Record external function names for useful debugging
adab9120 Support variable length attributes in SlotGetAttrCodegen.
335e09aa Proclaim that the codegen'ed version of generated functions are called in debug build
50fd9140 Fix cpplint errors
88a04412 Use ExprTreeGeneratorInfo for expression tree generation.
3b4af3bb Split code generation of ExecVariableList from slot_getattr
8cd9ed9f Support <= operator for date/timestamp data types and some minor refactors.
e4dccf46 Implement InlineFunction to force inline at call site
71170942 Mock postmaster.o for codegen_framework_unittest.t
09f00581 Codegen expressions that contain plus, minus and mul operators on float8 data types
d7fb2f6d Fix codegen unittests on Linux and various compiler warnings while building codegen.
45f2aa96 Fix test and update coding style This closes #874
1b26fbfc Enrolled targetlist for scan and aggregate
ebd1d014 Enhance codegen framework to support arbitrary expr tree
ec626ce6 Generate and enroll naive ExecEvalExpr in Scan's quals
1186001e Revert "Create naive code-generated version of ExecQual"
6f928a65 Replace RegisterExternalFunction with GetOrRegisterExternalFunction using an unordered_map in codegen_utils
6ae0085b Move ElogWrapper to GpCodegenUtils.
d3f80b45 Add verifyfunction for generated llvm function.
7bcf094a Fix codegen compiler error with 8.3 merge
aae0ad3d Create naive code-generated version of ExecQual
dce266ad Minor code quality fixes in src/backend/codegen
d281f340 Support null attributes in code generated ExecVariableList
82fd418e Address a number of cpplint errors in codegen_utils_unittest.cc
887aa48d Add check for CodegenUtils::GetType for bool arrays
bb9b92c6 Enhance Base Codegen to do clean up when generation fails
b9ef5e3f Fix build error for Annotated types
a5cfefd9 Add support for array types in codegen_utils.
2b883384 Fix static_assert call
7b75d9ea This commit  generates code for code path: ExecVariableList > slot_getattr > _slot_getsomeattrs > slot_deform_tuple. This code path is executed during scan in simple select queries that do not have a where clause (e.g., select bar from foo;).
6d0a06e8 Fix CodeGen typos and CodeGeneratorManagerCreate function signature in gpcodegen_mock.c
4916a606 Add support for registering vararg external functions with codegen utils.
ae4a7754 Integrate codegen framework and make simple external call to slot deform tuple. This closes #649
ee5fb851 Renaming code_generator to codegen_utils and CodeGenerator to CodegenUtils. This closes #648
88e9baba Adding GPDB code generation utils
Signed-off-by: NJesse Zhang <sbjesse@gmail.com>
Signed-off-by: NMelanie Plageman <mplageman@pivotal.io>
Signed-off-by: NSambitesh Dash <sdash@pivotal.io>

These were added in GPDB to encapsulate RelFileNode and persistent table
information. But persistent tables are no more, so there is no reason to
differ from upstream.

To reduce merge conflicts as we start to merge with upstream again.

With persistent tables removed there are no more consumers of this
API, so remove it.

The change in index.c is a behavioral change. The behavior on reindexing
shared catalogs now matches upstream again. The rest is just removal of
dead code.

A long time ago, they were disabled, because the GIN code had not been
modified to work with file replication. Now with WAL replication, there's
no reason to not support them.

After finding a match in semijoin mode, arrange to advance to
the next outer tuple not next inner tuple after returning the
current match. The node->mj_MatchedOuter is always false here,
there is no need to check it.

Author: Max Yang <myang@pivotal.io>

In the first cut of the walreplication work, I left out the part that
drops a segfile during AO compaction, because there was no
straightforward native PostgreSQL function to drop just a single segfile.
However, that leads to a massive disk space leak, as the space freed by
VACUUM on an AO table is not reclaimed, until the same segment number is
used again for further insertions, so we clearly must do something about
that.

Instead of dropping the segfile altogether, like we used to, truncate the
file to 0 bytes. Mostly because that's more expedient to do, as we have
the functions to do that and to WAL-log that, whereas code to fully remove
just a single segfile doesn't exist. But if you squint a bit, you could
even call that an optimization: it saves the overhead of recreating the
file again, if you load more data to it later.

Pointed out by Coverity.

As Coverity pointed out, 'pelem' has already been dereferenced in the
function, and hence it can never be NULL here. And indeed it should never
be NULL.

With 'prule', we explicitly checked for NULL earlier in the function.

A PL/JAVA NULL point reference has been reported by coverity scan.
The issue is located in guc.c for a pljava guc option
"pljava_classpath_insecure" and fixed in this commit.

tuple store which just advances current position by N instead of getting
tuple N times.

Author: Max Yang <myang@pivotal.io>

The timezone data in Greenplum are from the base version of
PostgreSQL that the current version of Greenplum is based on.
This cause issues since it means we are years behind on tz
changes that have happened. This pulls in the timezone data
and code from PostgreSQL 10.1 with as few changes to Greenplum
as possible to minimize merge conflicts. The goal is to gain
data rather than features, and for Greenplum for each release
to be able to stay current with the iana tz database as it is
imported into upstream PostgreSQL.

This removes a Greenplum specific test for the Yakutsk timezone
as it was made obsolete by upstream tz commit 1ac038c2c3f25f72.

This is mostly cherry-pick of upstream commit
commit 970a1868
Author: Robert Haas <rhaas@postgresql.org>
Date:   Fri Dec 3 08:44:15 2010 -0500

    Use GUC lexer for recovery.conf parsing.

    This eliminates some crufty, special-purpose code and, as a non-trivial
    side benefit, allows recovery.conf parameters to be unquoted.

    Dimitri Fontaine, with review and cleanup by Alvaro Herrera, Itagaki
    Takahiro, and me.

Originally, we skip probing primary without mirrors, however, we still
use the num_primary_segments to indicate number of requests. This caused
inconsistency when processing the response, since, not all the primary
segments got probe response.

The fix is to only track the actual number of probe requests sent.

Author: Xin Zhang <xzhang@pivotal.io>
Author: Ashwin Agrawal <aagrawal@pivotal.io>

- detect primary goes down
- flip the role to m/p/d/n and p/m/u/n (role/prefer/status/mode) in
  gp_segment_configuration
- send promotion message to mirror to promote it

Author: Xin Zhang <xzhang@pivotal.io>
Author: Jacob Champion <pchampion@pivotal.io>
Author: Asim R P <apraveen@pivotal.io>

It set the master_mirroring_administrator_disable variable, but it's not
used for anything. Remove the variable, and all the code to pass that flag
through.

It was now unused.

SetSyncStandbysDefined and friends are now much simpler; there isn't
really anything interesting to test anymore. We already have an
integration test that covers the operation for the whole cluster.

Revert SyncRepUpdateSyncStandbysDefined to its upstream contract: only
checkpointer may call it, and it acquires the SyncRepLock on its own.
If we don't need to ensure that the FTS responder sends back
syncrep=false immediately, the logic is vastly simplified, and we can
remove the assertion on the receiver end.

Also note that we don't need to set the GUC in memory directly; the
SIGHUP will load the new GUC from disk, further simplifying things here.

Author: Jacob Champion <pchampion@pivotal.io>
Author: Ashwin Agrawal <aagrawal@pivotal.io>

gp_remove_segment_persistent_entries() function doesn't exist any more.