pgsql: Add support for detecting register-stack overrun on IA64.

Add support for detecting register-stack overrun on IA64.

Per recent investigation, the register stack can grow faster than the
regular stack depending on compiler and choice of options.  To avoid
crashes we must check both stacks in check_stack_depth().

Back-patch to all supported versions.

Branch
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REL8_4_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=faa90079839343e7b350c869b45f496ea3e9a05c

Modified Files
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src/backend/tcop/postgres.c |   60 +++++++++++++++++++++++++++++++++++++++++++
1 files changed, 60 insertions(+), 0 deletions(-)