> We have a flag for this already on the CALL_EXPR. But we don't retain it > over tuples, and hence we also don't look at it in > inline_forbidden_p_stmt. This patch fixes both. (The strange testing of > builtin-ness is because in CALL_EXPR the ALLOCA_FOR_VAR_P and > CALL_FROM_THUNK_P flags are overloaded)
More precisely, we don't expose it on tuples; we do retain it over tuples since we tuplify CALL_FROM_THUNK_P and we rematerialize it in expand_call_stmt. The flag is later passed to expand_builtin_alloca. > * gimple.h (enum gf_mask): Add GF_CALL_ALLOCA_FOR_VAR. > (gimple_call_set_alloca_for_var): New inline function. > (gimple_call_alloca_for_var_p): Ditto. > * gimple.c (gimple_build_call_from_tree): Remember ALLOCA_FOR_VAR_P > state. > * cfgexpand.c (expand_call_stmt): Restore ALLOCA_FOR_VAR_P state. > > * tree-inline.c (inline_forbidden_p_stmt): Don't reject alloca > calls if they were for VLA objects. Nice patch. The idea also occurred to me recently because we often run into the inlining limitation in Ada. Btw, I don't remember why I chose ALLOCA_FOR_VAR_P over CALL_ALLOCA_FOR_VAR_P but, given the name of the GIMPLE flag and predicate, it's probably time to change it. -- Eric Botcazou
