of re_compile_fastmap and generalizing it a little bit so that it
can also just return whether a given (sub)pattern can match the empty
string or not.
(regex_compile): Use `analyse_first' to decide whether the loop-check
needs to be done or not for *, +, *? and +? (the loop check is costly
for non-greedy repetition).
(re_compile_fastmap): Delegate the actual work to `analyse_first'.
(enum re_opcode_t): Update description of succeed_n.
(PATFETCH): Always define.
(regex_compile): Use lookahead rather than PATUNFETCH (for repetition
operators, char classes, shy-groups and intervals).
Optimize special cases of intervals so as to only use succeed_n and
jump_n when really needed.
(re_compile_fastmap): Simplify handling of jump_n and succeed_n now
that we don't have to handle the special cases any more.
Simplify on_failure_jump handling as well.
(mark_memory): Use it.
(SETJMP_WILL_LIKELY_WORK, SETJMP_WILL_NOT_WORK): New macros.
(setjmp_tested_p, longjmp_done): New variables.
(test_setjmp): New function.
(mark_stack) [!GC_SETJMP_WORKS]: Call test_setjmp.
(init_alloc): Initialize setjmp_tested_p and longjmp_done.
(PER_BUFFER_VAR_OFFSET): Renamed from BUFFER_LOCAL_VAR_OFFSET.
(PER_BUFFER_VAR_IDX): Renamed from BUFFER_LOCAL_VAR_IDX.
(PER_BUFFER_VALUE_P): Renamed from BUFFER_HAS_LOCAL_VALUE_P.
(SET_PER_BUFFER_VALUE_P): Renamed from SET_BUFFER_HAS_LOCAL_VALUE_P.
(PER_BUFFER_IDX): Renamed from BUFFER_LOCAL_IDX.
(PER_BUFFER_DEFAULT): Renamed from BUFFER_LOCAL_DEFAULT_VALUE.
(PER_BUFFER_VALUE): Renamed from BUFFER_LOCAL_VALUE.
(PER_BUFFER_SYMBOL): Renamed from BUFFER_LOCAL_SYMBOL.
(PER_BUFFER_TYPE): Renamed from BUFFER_LOCAL_TYPE.
(print_partial_compiled_pattern, re_compile_fastmap): Handle new opcode.
(regex_compile): Use on_failure_jump_nastyloop for non-greedy loops.
(re_match_2_internal): Add code for on_failure_jump_nastyloop when
executing it as well as when popping it off the stack to find infinite
loops in non-greedy repetition operators.
(syms_of_doc): Initialize Qfunction_documentation.
(Fdocumentation): If FUNCTION is a symbol with non-nil
`function-documentation' property, return a documentation derived
from that.
(max_buffer_local_idx): New variable.
(reset_buffer_local_variables, Fbuffer_local_variables): Rewritten
for new handling of per-buffer variables.
(buffer_slot_type_mismatch): Use new macros for per-buffer vars.
(init_buffer_once): Initialize per-buffer vars differently.
Set max_buffer_local_idx.
