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_3_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=940de279ce4a626eebbf033cfa72767e85a0f885

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