One of the main motivating use cases for this language feature is
tracing/profiling tools, which expect null-terminated strings for these
values. Since the data is statically allocated, making them
additionally null-terminated comes at no cost.
This prevents the requirement of compile-time code to convert to
null-termination, which could increase the compilation time of
code with tracing enabled.
See #2029
- for one-possible-value types, ir_analyze_struct_field_ptr()
no longer hardcodes const/volatile
- when slicing arrays, ir_analyze_instruction_slice()
no longer consults ConstValSpecialStatic
closes#5474
extracted function ir_try_evaluate_bin_op_const
extracted type_is_self_comparable function
renamed ir_try_evaluate_bin_op_const to ir_try_evaluate_bin_op_cmp_const
implemented analysis of ?T == T
added ir_set_cursor_at_end_and_append_basic_block_gen
use build_br_gen and ir_set_cursor_at_end_and_append_block_gen
added ir_append_basic_block_gen
removed include of all_types in ir.cpp
extracted compile-time and runtime evaluation of cmp_optional_non_optional to separate functions
closes#5390closes#1332
The binary file abstraction changed its struct named "Decl" to
"TextBlock" and it now represents an allocated slice of memory in
the .text section. It has two new fields: prev and next, making it
a linked list node. This allows a TextBlock to find its neighbors.
The ElfFile struct now has free_list and last_text_block fields.
Doc comments for free_list are reproduced here:
A list of text blocks that have surplus capacity. This list can have false
positives, as functions grow and shrink over time, only sometimes being added
or removed from the freelist.
A text block has surplus capacity when its overcapacity value is greater than
minimum_text_block_size * alloc_num / alloc_den. That is, when it has so
much extra capacity, that we could fit a small new symbol in it, itself with
ideal_capacity or more.
Ideal capacity is defined by size * alloc_num / alloc_den.
Overcapacity is measured by actual_capacity - ideal_capacity. Note that
overcapacity can be negative. A simple way to have negative overcapacity is to
allocate a fresh text block, which will have ideal capacity, and then grow it
by 1 byte. It will then have -1 overcapacity.
The last_text_block keeps track of the end of the .text section.
Allocation, freeing, and resizing decls are all now more sophisticated,
and participate in the virtual address allocation scheme. There is no
longer the possibility for virtual address collisions.
Alexandros Naskos
antlilja
Andrew Kelley
xackus
Robin Voetter
Charlie Stanton
Ryan Liptak
Vexu
Noam Preil
Jakub Konka
Jonathan Marler
Michael Dusan
foobles
Timon Kruiper