Also fixed abiAlignment - for pointers it was returning the abi
alignment inside the type, rather than of the pointer itself. There is
now `ptrAlignment` for getting the alignment inside the type of
pointers.
* zir.Code: introduce a decls array. This is so that `decl_val` and
`decl_ref` instructions can refer to a Decl with a u32 and therefore
they can also store a source location. This is needed for proper
compile error reporting.
* astgen uses a hash map to avoid redundantly adding a Decl to the
decls array.
* fixed reporting "instruction illegal outside function body" instead
of the desired message "unable to resolve comptime value".
* astgen skips emitting dbg_stmt instructions in comptime scopes.
* astgen has some logic to avoid adding unnecessary type coercion
instructions for common values.
Introduce "inline" variants of ZIR tags:
* block => block_inline
* repeat => repeat_inline
* break => break_inline
* condbr => condbr_inline
The inline variants perform control flow at compile-time, and they
utilize the return value of `Sema.analyzeBody`.
`analyzeBody` now returns an Index, not a Ref, which is the ZIR index of
a break instruction. This effectively communicates both the intended
break target block as well as the operand, allowing parent blocks to
find out whether they, in turn, should return the break instruction up the
call stack, or accept the operand as the block's result and continue
analyzing instructions in the block.
Additionally:
* removed the deprecated ZIR tag `block_comptime`.
* removed `break_void_node` so that all break instructions use the same Data.
* zir.Code: remove the `root_start` and `root_len` fields. There is now
implied to be a block at index 0 for the root body. This is so that
`break_inline` has something to point at and we no longer need the
special instruction `break_flat`.
* implement source location byteOffset() for .node_offset_if_cond
.node_offset_for_cond is probably redundant and can be deleted.
We don't have `comptime var` supported yet, so this commit adds a test
that at least makes sure the condition is required to be comptime known
for `inline while`.
* comment out the failing stage2 test cases
(so that we can uncomment the ones that are newly passing with
further commits)
* Sema: implement negate, negatewrap
* astgen: implement field access, multiline string literals, and
character literals
* Module: when resolving an AST node into a byte offset, use the
main_tokens array, not the firstToken function
* Now it supports being an lvalue (see additional lines in the test
case).
* Properly handles a pointer result location (see additional lines in
the test case that assign the result of the orelse to a variable
rather than a const).
* Properly sets the result location type when possible, so that type
inference of an `orelse` operand expression knows its result type.
We can now codegen optionals! This includes the following instructions:
- is_null
- is_null_ptr
- is_non_null
- is_non_null_ptr
- optional_payload
- optional_payload_ptr
- br_void
Also includes a test for optionals.
All stage2 tests are passing again in this branch.
Remaining checklist for this branch:
* get the rest of the zig fmt test cases passing
- re-enable the translate-c test case that is blocking on this
* implement the 2 `@panic(TODO)`'s in parse.zig
* use fn_proto not fn_decl for extern function declarations
The astgen for switch expressions did not respect the ZIR rules of only
referencing instructions that are in scope:
%14 = block_comptime_flat({
%15 = block_comptime_flat({
%16 = const(TypedValue{ .ty = comptime_int, .val = 1})
})
%17 = block_comptime_flat({
%18 = const(TypedValue{ .ty = comptime_int, .val = 2})
})
})
%19 = block({
%20 = ref(%5)
%21 = deref(%20)
%22 = switchbr(%20, [%15, %17], {
%15 => {
%23 = const(TypedValue{ .ty = comptime_int, .val = 1})
%24 = store(%10, %23)
%25 = const(TypedValue{ .ty = void, .val = {}})
%26 = break("label_19", %25)
},
%17 => {
%27 = const(TypedValue{ .ty = comptime_int, .val = 2})
%28 = store(%10, %27)
%29 = const(TypedValue{ .ty = void, .val = {}})
%30 = break("label_19", %29)
}
}, {
%31 = unreachable_safe()
}, special_prong=else)
})
In this snippet you can see that the comptime expr referenced %15 and
%17 which are not in scope. There also was no test coverage for runtime
switch expressions.
Switch expressions will have to be re-introduced to follow these rules
and with some test coverage. There is some usable code being deleted in
this commit; it will be useful to reference when re-implementing switch
later.
A few more improvements to do while we're at it:
* only use .ref result loc on switch target if any prongs obtain the
payload with |*syntax|
- this improvement should be done to if, while, and for as well.
- this will remove the needless ref/deref instructions above
* remove switchbr and add switch_block, which is both a block and a
switch branch.
- similarly we should remove loop and add loop_block.
This commit introduces a "force_comptime" flag into the GenZIR
scope. The main purpose of this will be to choose the "comptime"
variants of certain key zir instructions, such as function calls and
branches. We will be moving away from using the block_comptime_flat
ZIR instruction, and eventually deleting it.
This commit also contains miscellaneous fixes to this branch that bring
it to the state of passing all the tests.
The following AST avoids unnecessary derefs now:
* error set decl
* field access
* array access
* for loops: replace ensure_indexable and deref on the len_ptr with a
special purpose ZIR instruction called indexable_ptr_len.
Added an error note when for loop operand is the wrong type.
I also accidentally implemented `@field`.
When codegen ends in failure, we need to manually clean up any fixups
that may have been gathered during that `codegen.generateSymbol` call.
Otherwise, we will end trapping.
* Implement error notes
- note: other symbol exported here
- note: previous else prong is here
- note: previous '_' prong is here
* Add Compilation.CObject.ErrorMsg. This object properly converts to
AllErrors.Message when the time comes.
* Add Compilation.CObject.failure_retryable. Properly handles
out-of-memory and other transient failures.
* Introduce Module.SrcLoc which has not only a byte offset but also
references the file which the byte offset applies to.
* Scope.Block now contains both a pointer to the "owner" Decl and the
"source" Decl. As an example, during inline function call, the
"owner" will be the Decl of the caller and the "source" will be the
Decl of the callee.
* Module.ErrorMsg now sports a `file_scope` field so that notes can
refer to source locations in a file other than the parent error
message.
* Some instances where a `*Scope` was stored, now store a
`*Scope.Container`.
* Some methods in the `Scope` namespace were moved to the more specific
type, since there was only an implementation for one particular tag.
- `removeDecl` moved to `Scope.Container`
- `destroy` moved to `Scope.File`
* Two kinds of Scope deleted:
- zir_module
- decl
* astgen: properly use DeclVal / DeclRef. DeclVal was incorrectly
changed to be a reference; this commit fixes it. Fewer ZIR
instructions processed as a result.
- declval_in_module is renamed to declval
- previous declval ZIR instruction is deleted; it was only for .zir
files.
* Test harness: friendlier diagnostics when an unexpected set of errors
is encountered.
* zir_sema: fix analyzeInstBlockFlat by properly calling resolvingInst
on the last zir instruction in the block.
Compile log implementation:
* Write to a buffer rather than directly to stderr.
* Only keep track of 1 callsite per Decl.
* No longer mutate the ZIR Inst struct data.
* "Compile log statement found" errors are only emitted when there are
no other compile errors.
-femit-zir and support for .zir source files is regressed. If we wanted
to support this again, outputting .zir would need to be done as yet
another backend rather than in the haphazard way it was previously
implemented.
For parsing .zir, it was implemented previously in a way that was not
helpful for debugging. We need tighter integration with the test harness
for it to be useful; so clearly a rewrite is needed. Given that a
rewrite is needed, and it was getting in the way of progress and
organization of the rest of stage2, I regressed the feature.
In rare occassions, it may happen that string table is allocated free
space preceeding symbol table. This is an error in the eyes of the `dyld`
dynamic loader and thus has to forbidden by the linker.
