These changes enable a Hello World example. However, all implemented
codegen is not yet feature-complete.
- asm only supports 'svc #0' at the moment
- call only supports leaf functions at the moment
- setReg uses a naive method at the moment
I forgot to do -Denable-qemu -Denable-wasmtime when testing yesterday,
sorry about that.
In reuseOperand, the code assumed a re-used register would be tracked in
the register table but that is not always the case.
See #6113 for an alternate way of doing this that we didn't end up
following.
Closes#6079.
I also took the opportunity here to extract C.zig and Elf.zig from
link.zig.
* Implemented all R-type arithmetic/logical instructions
* Implemented all I-type arithmetic/logical instructions
* Implemented all load and store instructions
* Implemented all of RV64I except FENCE
* introduce a dump() function on Module.Fn which helpfully prints to
stderr the ZIR representation of a function (can be called before
attempting to codegen it). This is a debugging tool.
* implement x86 codegen for loops
* liveness: fix analysis of conditional branches. The logic was buggy
in a couple ways:
- it never actually saved the results into the IR instruction (fixed now)
- it incorrectly labeled operands as dying when their true death was
after the conditional branch ended (fixed now)
* zir rendering is enhanced to show liveness analysis results. this
helps when debugging liveness analysis.
* fix bug in zir rendering not numbering instructions correctly
closes#6021
* the .debug_line header is written properly
* link.File.Elf gains:
- SrcFn, which is now a field in Module.Fn
- SrcFile, which is now a field in Module.Scope.File
* link.File.Elf gets a whole *Package field rather than only
root_src_dir_path.
* the fields first_dbg_line_file and last_dbg_line_file tell where the
Line Number Program begins and ends, which alows moving files when
the header gets too big, and allows appending files to the end.
* codegen is passed a buffer for emitting .debug_line
Line Number Program opcodes for functions.
See #5963
There is some work-in-progress code here, but I need to go make some
experimental changes to changing how to represent source locations and I
want to do that in a separate commit.
* multiple returns jump to one canonical function exitlude. This is in
preparation for the defer feature.
* simple elision of trivial jump relocs.
* omit prelude/exitlude for naked calling convention functions.
* fix not switching on arch for prelude/exitlude
* fix swapped registers when setting stack mem from a register
* `optimize_mode` is passed to `link.File` and stored there
* improve the debugging function `Module.dumpInst`
* get rid of `Value.the_one_possible_value` in favor of a few more
specific values for different types. This is less buggy, one less
footgun.
* `Type.onePossibleValue` now returns a `?Value` instead of `bool`.
* codegen handles undefined values. `undef` is a new `MCValue` tag.
It uses 0xaa values depending on optimization mode. However
optimization mode does not yet support scope overrides.
* link.zig: move the `Options` field from `File.Elf` and `File.C` to
the base struct.
- fix the Tag enum to adhere to style conventions
* ZIR now supports emitting undefined values.
* Fix the logic of comptime math to properly compare against zero using
the `compareWithZero` function.
* implement sema for runtime deref, store pointer, coerce_to_ptr_elem,
and store
* identifiers support being lvalues, except for decls is still TODO
* codegen supports load, store, ref, alloc
* introduce more MCValue union tags to support pointers
* add load, ref, store typed IR instructions
* add Type.isVolatilePtr
