Rather than storing all the shifts in temporaries, we perform the correct
shifting without temporaries. This makes the runtime code more performant
and also the backend code is simplified as we have a singular abstraction.
This does however not support floats of bitsizes
different than 32 or 64. f16, f80, f126 will require
support for compiler-rt and are out-of-scope for this commit.
Signed integers are currently not supported either.
And use it to debug a LazySrcLoc in stage2 that is set to a bogus value.
The actual fix in this commit is:
```diff
- try sema.emitBackwardBranch(&child_block, call_src);
+ try sema.emitBackwardBranch(block, call_src);
```
Split type relocs into two kinds: local and global. Global relocs
use a global type resolver and calculate offset to the existing
definition of a type abbreviation.
Local relocs use offset in the abbrev section of the containing
atom plus addend to generate a local relocation.
Implements semantic analysis for the new try/try_inline ZIR
instruction. Adds the new try/try_ptr AIR instructions and implements
them for the LLVM backend.
Fixes not calling rvalue() for tryExpr in AstGen.
This is part of an effort to implement #11772.
* `?E` where E is an error set with only one field now lowers the same
as `bool`.
* Fix implementation of errUnionErrOffset and errUnionPayloadOffset to
properly compute the offset of each field. Also name them the same
as the corresponding LLVM functions and have the same function
signature, to avoid confusion. This fixes a bug where wasm was
passing the error union type instead of the payload type.
* Fix C backend handling of optionals with zero-bit payload types.
* C backend: separate out airOptionalPayload and airOptionalPayloadPtr
which reduces branching and cleans up control flow.
* Make Type.isNoReturn return true for error sets with no fields.
* Make `?error{}` have only one possible value (null).
This also fixes the instruction for all other integer bitsizes,
as it was previously assuming to always be a bool.
128 bit substraction was also fixed as it contained a bug where it swapped
lhs with rhs.
This also implments wrapping for arbitrary integer widths between 64 and 128.
`@truncate` was fixed where the wasm types between operand and result differentiated.
We solved this by first casting and then wrapping.
`airMaxMin` was slightly updated to automatically support 128 bit integers,
by using the `cmp` function, instead of doing it manually. This makes the function
more maintanable as well.
`ctz` and `clz` now support 128 bit integers, while updating the previous implementation
also.
We now pass the correct wasm type when the return type is a 128-bit integer.
When a function accepts a 128-bit integer, we now allocate space on the virtual stack
and store both arguments within that space as currently all following instructions
assume the 128 bit integer doesn't live in a local, but the stack.
This implements support for all compare operations on a 128bit integer,
for both signed and unsigned integers.
The new implementation is almost more efficient as it requires no control-flow,
unlike the old implementation which used a block with breaks.
The implementation for add_with_overflow and sub_with_overflow is now a lot
more robust and takes account for signed integers and arbitrary integer bitsizes.
The final output is equal to that of the LLVM backend.
Maps lines and columns between wasm bytecode and Zig source code.
While this supports prologue and epilogue information, we need to add
support for performing relocations as the offsets are relative to the code section,
which means we must relocate it according to the atom offset's offset while keeping function count
in mind as well (due to leb128 encoding).
Implements very basic debug information for locals.
For now it only implements debug info when the variable is stored within a
Wasm local. The goal is to support those that live in the data section (virtual stack).
As we now store negative signed integers as two's complement,
we must also ensure that when truncating a float, its value is wrapped
around the integer's size.
This also splits `@mulWithOverflow` into its own function to make
the code more maintainable and reduce branching.
When a signed integer is negative, the integer will be stored as a two's complement,
rather than its signed value. Instead, we verify the signed bits during arithmetic operations.
This fixes signed cases of `@mulWithOverflow`.
The reason for having `@tan` is that we already have `@sin` and `@cos`
because some targets have machine code instructions for them, but in the
case that the implementation needs to go into compiler-rt, sin, cos, and
tan all share a common dependency which includes a table of data. To
avoid duplicating this table of data, we promote tan to become a builtin
alongside sin and cos.
ZIR: The tag enum is at capacity so this commit moves
`field_call_bind_named` to be `extended`. I measured this as one of
the least used tags in the zig codebase.
Fix libc math suffix for `f32` being wrong in both stage1 and stage2.
stage1: add missing libc prefix for float functions.
Rather than allocating Decl objects with an Allocator, we instead allocate
them with a SegmentedList. This provides four advantages:
* Stable memory so that one thread can access a Decl object while another
thread allocates additional Decl objects from this list.
* It allows us to use u32 indexes to reference Decl objects rather than
pointers, saving memory in Type, Value, and dependency sets.
* Using integers to reference Decl objects rather than pointers makes
serialization trivial.
* It provides a unique integer to be used for anonymous symbol names,
avoiding multi-threaded contention on an atomic counter.
When the last instruction is a debug instruction, the type of it is void.
Similarly for 'noreturn' emit an 'unreachable' instruction to tell the wasm-validator
the path cannot be reached.
Also respect the '--strip' flag in the self-hosted wasm linker and not emit a 'name' section
when the flag is set to `true`.
* The `@bitCast` workaround is removed in favor of `@ptrCast` properly
doing element casting for slice element types. This required an
enhancement both to stage1 and stage2.
* stage1 incorrectly accepts `.{}` instead of `{}`. stage2 code that
abused this is fixed.
* Make some parameters comptime to support functions in switch
expressions (as opposed to making them function pointers).
* Avoid relying on local temporaries being mutable.
* Workarounds for when stage1 and stage2 disagree on function pointer
types.
* Workaround recursive formatting bug with a `@panic("TODO")`.
* Remove unreachable `else` prongs for some inferred error sets.
All in effort towards #89.
Rather than using blocks and control flow to check which operand is the maximum or minimum,
we use wasm's `select` instruction which returns us the operand based on a result from a comparison.
This saves us the need of control flow, as well as reduce the instruction count from 13 to 7.
Implements the `ctz` AIR instruction for integers with bitsize <= 64.
When the bitsize of the integer does not match the bitsize of a wasm type,
we first XOR the value with the value of (1<<bitsize) to set the right bits
and ensure we will only count the trailing zeroes of the integer with the correct bitsize.
Implements the `clz` AIR instruction for integers with bitsize <= 64.
When the bitsize of the integer is not the same as wasm's bitsize,
we substract the difference in bits as those will always be 0 for the integer, but should
not be counted towards the end result. We also wrap the result to ensure it fits
in the result type as documented in the language reference.
This implements the `mul_add` AIR instruction for floats of bitsize 32 and 64.
f16's will require us being able to extend and truncate f16's to correctly
store and load them without losing the accuracy.
This implements the `max` and `min` AIR instructions by checking
whether LHS is great/lesser than RHS. If that's the case, we assign
LHS to the result, otherwise assign RHS to it instead.
