Horton

Re: remaining sql/json patches

amit <amitlangote09@gmail.com>

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From: Amit Langote <amitlangote09@gmail.com>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
Cc: Andrew Dunstan <andrew@dunslane.net>, Erik Rijkers <er@xs4all.nl>, PostgreSQL-development <pgsql-hackers@postgresql.org>, jian he <jian.universality@gmail.com>
Date: 2023-10-06T09:23:37Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. SQL/JSON: Various improvements to SQL/JSON query function docs

  2. SQL/JSON: Fix some obsolete comments.

  3. SQL/JSON: Fix issues with DEFAULT .. ON ERROR / EMPTY

  4. JSON_TABLE: Add support for NESTED paths and columns

  5. Fix JsonExpr deparsing to emit QUOTES and WRAPPER correctly

  6. Fix typo introduced in 6185c9737

  7. Add basic JSON_TABLE() functionality

  8. Avoid splitting errmsg string to span multiple lines

  9. Add SQL/JSON query functions

  10. Implement various jsonpath methods

  11. Add soft error handling to some expression nodes

  12. Adjust populate_record_field() to handle errors softly

  13. Refactor code used by jsonpath executor to fetch variables

  14. Test EXPLAIN (FORMAT JSON) ... XMLTABLE

  15. Simplify productions for FORMAT JSON [ ENCODING name ]

  16. Add trailing commas to enum definitions

  17. doc: add missing <returnvalue> and whitespace

  18. Add more SQL/JSON constructor functions

  19. Rename a nonterminal used in SQL/JSON grammar

  20. Some refactoring to export json(b) conversion functions

  21. Don't include CaseTestExpr in JsonValueExpr.formatted_expr

  22. Code review for commit b6e1157e7d

  23. Pass constructName to transformJsonValueExpr()

  24. Unify JSON categorize type API and export for external use

  25. Make some indentation in gram.y consistent

  26. Allow most keywords to be used as column labels without requiring AS.

  27. Reduce size of backend scanner's tables.

  28. Use perfect hashing, instead of binary search, for keyword lookup.

Attachments

On Wed, Oct 4, 2023 at 10:26 PM Amit Langote <amitlangote09@gmail.com> wrote:
> On Tue, Oct 3, 2023 at 10:11 PM Amit Langote <amitlangote09@gmail.com> wrote:
> > On Mon, Oct 2, 2023 at 2:26 PM Amit Langote <amitlangote09@gmail.com> wrote:
> > > On Mon, Oct 2, 2023 at 1:24 PM Amit Langote <amitlangote09@gmail.com> wrote:
> > > > Pushed this 30 min ago (no email on -committers yet!) and am looking
> > > > at the following llvm crash reported by buildfarm animal pogona [1]:
> > > > This seems to me to be complaining about the following addition:
> > > >
> > > > +                   {
> > > > +                       Oid         ioparam = op->d.iocoerce.typioparam;
> > > > +                       LLVMValueRef v_params[6];
> > > > +                       LLVMValueRef v_success;
> > > > +
> > > > +                       v_params[0] = l_ptr_const(op->d.iocoerce.finfo_in,
> > > > +                                                 l_ptr(StructFmgrInfo));
> > > > +                       v_params[1] = v_output;
> > > > +                       v_params[2] = l_oid_const(lc, ioparam);
> > > > +                       v_params[3] = l_int32_const(lc, -1);
> > > > +                       v_params[4] = l_ptr_const(op->d.iocoerce.escontext,
> > > > +
> > > > l_ptr(StructErrorSaveContext));
> > > >
> > > > -                   LLVMBuildStore(b, v_retval, v_resvaluep);
> > > > +                       /*
> > > > +                        * InputFunctionCallSafe() will write directly into
> > > > +                        * *op->resvalue.
> > > > +                        */
> > > > +                       v_params[5] = v_resvaluep;
> > > > +
> > > > +                       v_success = LLVMBuildCall(b, llvm_pg_func(mod,
> > > > "InputFunctionCallSafe"),
> > > > +                                                 v_params, lengthof(v_params),
> > > > +                                                 "funccall_iocoerce_in_safe");
> > > > +
> > > > +                       /*
> > > > +                        * Return null if InputFunctionCallSafe() encountered
> > > > +                        * an error.
> > > > +                        */
> > > > +                       v_resnullp = LLVMBuildICmp(b, LLVMIntEQ, v_success,
> > > > +                                                  l_sbool_const(0), "");
> > > > +                   }
> > >
> ...I haven't yet pinpointed down
> which of the LLVM's asserts it is, nor have I been able to walk
> through LLVM source code using gdb to figure what the new code is
> doing wrong.  Maybe I'm still missing a trick or two...

I finally managed to analyze the crash by getting the correct LLVM build.

So the following bits are the culprits:

1. v_output needed to be converted from being reference to a Datum to
be reference to char * as follows before passing to
InputFunctionCallSafe():

-                       v_params[1] = v_output;
+                       v_params[1] = LLVMBuildIntToPtr(b, v_output,
+
l_ptr(LLVMInt8TypeInContext(lc)),
+                                                       "");

2. Assignment of op->d.iocoerce.escontext needed to be changed like this:

                        v_params[4] = l_ptr_const(op->d.iocoerce.escontext,
-
l_ptr(StructErrorSaveContext));
+                                                 l_ptr(StructNode));

3. v_success needed to be "zero-extended" to match in type with
whatever s_bool_const() produces, as follows:

+                       v_success = LLVMBuildZExt(b, v_success,
TypeStorageBool, "");
                        v_resnullp = LLVMBuildICmp(b, LLVMIntEQ, v_success,
                                                   l_sbool_const(0), "");

No more crashes with the above fixes.

Attached shows the delta against the patch I reverted.  I'll push the
fixed up version on Monday.

-- 
Thanks, Amit Langote
EDB: http://www.enterprisedb.com