gdb: add -catch-hiperr to the Machine Interface (MI)

[amd-shahab]

Introduce a new MI command to catch HIP runtime errors that takes the form of:

  -catch-hiperr [ -c <condition>] [ -t ]

Along with it the documentation is updated and new tests are added.

Motivation

Add Machine Interface for "catch hiperr".

Technical Details

Machine Interface allows other tools control GDB by sending it commands and reading its feedback. This was missing for the "catch hiperr" support that we added earlier.

Test Plan

A new test with 4 different scenarios are added (see gdb.rocm/mi-catch-hiperr.exp).

Test Result

All the new tests are and "catch hiperr" tests are passing.

Running /data/work/src/dev/rocgdb/gdb/testsuite/gdb.rocm/mi-catch-hiperr.exp ...
PASS: gdb.rocm/mi-catch-hiperr.exp: simple catch
PASS: gdb.rocm/mi-catch-hiperr.exp: breakpoint info of simple catch
PASS: gdb.rocm/mi-catch-hiperr.exp: temporary catch
PASS: gdb.rocm/mi-catch-hiperr.exp: breakpoint info of temporary catch
PASS: gdb.rocm/mi-catch-hiperr.exp: conditional catch
PASS: gdb.rocm/mi-catch-hiperr.exp: breakpoint info of conditional catch
PASS: gdb.rocm/mi-catch-hiperr.exp: temporary conditional catch
PASS: gdb.rocm/mi-catch-hiperr.exp: breakpoint info of temporary conditional catch

[lancesix]

First very quick remarks.

[lancesix]

usual parsing question… How do you differentiate -t as a flag after the condition v.s. -t being the unari - operator, i.e. hipErrorInvalidDevice - t?

[amd-shahab]

Debugging the code around the option parsing [1], reveals that the valid ways of passing arguments to options (in this example, condition to -c) is to not use any spaces in the argument or have them double-quoted. For instance, see the two alternatives below and how they end up setting the parameters:

# alt.1: no spaces
interpreter-exec mi '-catch-hiperr -c $_hiperr=hipErrorInvalidDevice-t -t'

mi_cmd_catch_hiperr (..., const char *const argv, int argc)
  argc: 3
  argv[0]: "-c"
  argv[1]: "$_hiperr==hipErrorInvalidDevice-t"
  argv[2]: "-t"
  .
  .
  .
  condition = "$_hiperr==hipErrorInvalidDevice-t"
  temp = true

---------------------------------------------------
# alt.2: double-quoted
interpreter-exec mi '-catch-hiperr -c "$_hiperr == hipErrorInvalidDevice - t" -t'

mi_cmd_catch_hiperr (..., const char *const argv, int argc)
  argc: 3
  argv[0]: "-c"
  argv[1]: "$_hiperr == hipErrorInvalidDevice - t"
  argv[2]: "-t"
  .
  .
  .
  condition = "$_hiperr == hipErrorInvalidDevice - t"
  temp = true

Any deviation from this and we'll end up with the wrong argc/argv to begin with:

interpreter-exec mi '-catch-hiperr -c $_hiperr == hipErrorInvalidDevice - t -t'

mi_cmd_catch_hiperr (..., const char *const argv, int argc)
  argc: 7
  argv[0]: "-c"
  argv[1]: "$_hiperr"
  argv[2]: "=="
  argv[3]: "hipErrorInvalidDevice"
  argv[4]: "-"
  argv[5]: "t"
  argv[6]: "-t"
  .
  .
  .
  condition = "$_hiperr"
  then "opt" in the for-loop [1] becomes negative and the loop is broken
  and we'll end up with a conditional catchpoint with $_hiperr as its condition.

[1] gdb/mi/mi-cmd-catch.c

void mi_cmd_catch_hiperr (const char *cmd, const char *const *argv, int argc)
{
  ...
  for (;;)
    {
      int opt = mi_getopt (cmd, argc, argv, opts, &oind, &oarg);

      if (opt < 0)
        break;

      switch ((enum opt) opt)
        {
        case OPT_CONDITION:
          condition = oarg;
          break;
        case OPT_TEMP:
          temp = true;
          break;
        }
    }
  ...
}

For the record, I've added -catch-hiperr -c "$_hiperr == hipErrorInvalidDevice -t" -t as a test now.

[amd-shahab]

• Use -catch-hiperr -c "$_hiperr == hipErrorInvalidDevice -t" -t as temporary conditional test
• Use mi_gdb_tests instead of gdb_test and gdb_test_multiple
• get rid of the rocm boiler plates (load_lib rocm.exp, require allow_hip_tests, and the standard_testfile .../prepare_for_testing ...)