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().

Since this is poorly-tested code, committing only to HEAD for the
moment ... but we might want to consider back-patching later.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=d7a2ce4905da7d812407b6354f038aac17e97024

Modified Files
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src/backend/tcop/postgres.c |   61 +++++++++++++++++++++++++++++++++++++++++++
1 files changed, 61 insertions(+), 0 deletions(-)