Currently Zig lowers `@intToFloat` for f80 incorrectly on non-x86
targets:
```
broken LLVM module found:
UIToFP result must be FP or FP vector
%62 = uitofp i64 %61 to i128
SIToFP result must be FP or FP vector
%66 = sitofp i64 %65 to i128
```
This happens because on such targets, we use i128 instead of x86_fp80 in
order to avoid "LLVM ERROR: Cannot select". `@intToFloat` must be
lowered differently to account for this difference as well.
LLVM bitcast wants integers that match the number of bits. So the const
bitcast has to use an i80, not an i128.
This commit makes the behavior tests fail for me, so it seems I did not
correctly construct the type. But it gets rid of the LLVM segfault.
I noticed that the strategy of memcpy the buf worked if I simply did an
LLVMConstTrunc() on the i128 to make it into an i80 before the
LLVMConstBitCast().
But is that correct in the face of different endianness? I'm not sure.
Instead use the standarized option for communicating the
zig compiler backend at comptime, which is `zig_backend`. This was
introduced in commit 1c24ef0d0b.
This exposes a function from stage2 to stage1 to append symbols to automatically export them.
This happends under the following conditions:
- Target is wasm
- User has not provided --export/--rdynamic flags themselves.
Make `@returnAddress()` return for the BPF target, as the BPF target for
the time being does not support probing for the return address. Stack
traces for the general purpose allocator for the BPF target is also set
to not be captured.
The target abi can also be set in build.zig via LibExeObjStep.target_abi
The value passed in is checked that it is a valid value in
std.Target.TargetAbi
The target abi is also validated against the target cpu
* stage1: change the `@typeName` of `@TypeOf(undefined)`,
`@TypeOf(null)`, and `@TypeOf(.foo)` to match stage2.
* move passing behavior tests to the passing-for-stage2 section.
This is mainly because arm64 macOS doesn't support all
versions supported by x86_64 macOS. This is just a temporary
thing until both architectures support the same set of OSes.
According to the documentation, `divTrunc` is "Truncated division.
Rounds toward zero". Lower it as a straightforward fdiv + trunc sequence
to make it behave as expected with mixed positive/negative operands.
Closes#10001
* move fmaq from freestanding libc to compiler_rt, unconditionally
exported weak_odr.
* stage1: add fmaf, fmal, fmaq as symbols that compiler-rt might
generate calls to.
* stage1: lower `@mulAdd` directly to a call to `fmaq` instead of to
the LLVM intrinsic because LLVM will lower it to `fmal` even when the
target's `long double` is not equivalent to `f128`.
This commit is intended to fix the test suite which is failing on the
previous commit.
* Remove the builtins `@addWithSaturation`, `@subWithSaturation`,
`@mulWithSaturation`, and `@shlWithSaturation` now that we have
first-class syntax for saturating arithmetic.
* langref: Clarify the behavior of `@shlExact`.
* Ast: rename `bit_shift_left` to `shl` and `bit_shift_right` to `shr`
for consistency.
* Air: rename to include underscore separator with consistency with
the rest of the ops.
* Air: add shl_exact instruction
* Use non-extended tags for saturating arithmetic, to keep it
simple so that all the arithmetic operations can be done the same
way.
- Sema: unify analyzeArithmetic with analyzeSatArithmetic
- implement comptime `+|`, `-|`, and `*|`
- allow float operands to saturating arithmetic
* `<<|` allows any integer type for the RHS.
* C backend: fix rebase conflicts
* LLVM backend: reduce the amount of branching for arithmetic ops
* zig.h: fix magic number not matching actual size of C integer types
- adds initial support for the operators +|, -|, *|, <<|, +|=, -|=, *|=, <<|=
- uses operators in addition to builtins in behavior test
- adds binOpExt() and assignBinOpExt() to AstGen.zig. these need to be audited
Introduce an explicit decl_map for *Decl to LLVMValueRef. Doc comment
reproduced here:
Ideally we would use `llvm_module.getNamedFunction` to go from *Decl to
LLVM function, but that has some downsides:
* we have to compute the fully qualified name every time we want to do the lookup
* for externally linked functions, the name is not fully qualified, but when
a Decl goes from exported to not exported and vice-versa, we would use the wrong
version of the name and incorrectly get function not found in the llvm module.
* it works for functions not all globals.
Therefore, this table keeps track of the mapping.
Non-exported functions now use fully-qualified symbol names.
`Module.Decl.getFullyQualifiedName` now returns a sentinel-terminated
slice which is useful to pass to LLVMAddFunction.
Instead of using aliases for all external symbols, now the LLVM backend
takes advantage of LLVMSetValueName to rename functions that become
exported. Aliases are still used for the second and remaining exports.
freeDecl is now handled properly in the LLVM backend, deleting the
LLVMValueRef corresponding to the Decl being deleted. The linker
backends for ELF, COFF, Mach-O, and Wasm had to be updated to forward
the freeDecl call to the LLVM backend.
* prepare compiler-rt to support being compiled by stage2
- put in a few minor workarounds that will be removed later, such as
using `builtin.stage2_arch` rather than `builtin.cpu.arch`.
- only try to export a few symbols for now - we'll move more symbols
over to the "working in stage2" section as they become functional
and gain test coverage.
- use `inline fn` at function declarations rather than `@call` with an
always_inline modifier at the callsites, to avoid depending on the
anonymous array literal syntax language feature (for now).
* AIR: replace floatcast instruction with fptrunc and fpext for
shortening and widening floating point values, respectively.
* Introduce a new ZIR instruction, `export_value`, which implements
`@export` for the case when the thing to be exported is a local
comptime value that points to a function.
- AstGen: fix `@export` not properly reporting ambiguous decl
references.
* Sema: handle ExportOptions linkage. The value is now available to all
backends.
- Implement setting global linkage as appropriate in the LLVM
backend. I did not yet inspect the LLVM IR, so this still needs to
be audited. There is already a pending task to make sure the alias
stuff is working as intended, and this is related.
- Sema almost handles section, just a tiny bit more code is needed in
`resolveExportOptions`.
* Sema: implement float widening and shortening for both `@floatCast`
and float coercion.
- Implement the LLVM backend code for this as well.
Conflicts:
* cmake/Findclang.cmake
* cmake/Findlld.cmake
* cmake/Findllvm.cmake
In master branch, more search paths were added to these files with "12"
in the path. In this commit I updated them to "13".
* src/stage1/codegen.cpp
* src/zig_llvm.cpp
* src/zig_llvm.h
In master branch, ZigLLVMBuildCmpXchg is improved to add
`is_single_threaded`. However, the LLVM 13 C API has this already, and
in the llvm13 branch, ZigLLVMBuildCmpXchg is deleted in favor of the C
API. In this commit I updated stage2 to use the LLVM 13 C API rather
than depending on an improved ZigLLVMBuildCmpXchg.
Additionally, src/target.zig largestAtomicBits needed to be updated to
include the new m68k ISA.
* Implement Sema for `@cmpxchgWeak` and `@cmpxchgStrong`. Both runtime
and comptime codepaths are implement.
* Implement Codegen for LLVM backend and C backend.
* Add LazySrcLoc.node_offset_builtin_call_argX 3...5
* Sema: rework comptime control flow.
- `error.ComptimeReturn` is used to signal that a comptime function
call has returned a result (stored in the Inlining struct).
`analyzeCall` notices this and handles the result.
- The ZIR instructions `break_inline`, `block_inline`,
`condbr_inline` are now redundant and can be deleted. `break`,
`block`, and `condbr` function equivalently inside a comptime scope.
- The ZIR instructions `loop` and `repeat` also are modified to
directly perform comptime control flow inside a comptime scope,
skipping an unnecessary mechanism for analysis of runtime code.
This makes Zig perform closer to an interpreter when evaluating
comptime code.
* Sema: zirRetErrValue looks at Sema.ret_fn_ty rather than sema.func
for adding to the inferred error set. This fixes a bug for
inlined/comptime function calls.
* Implement ZIR printing for cmpxchg.
* stage1: make cmpxchg respect --single-threaded
- Our LLVM C++ API wrapper failed to expose this boolean flag before.
* Fix AIR printing for struct fields showing incorrect liveness data.
- adds 1 simple behavior tests for each
which does integer and vector ops at
runtime and comptime
- adds bigint_*_sat() methods for each
- use CreateIntrinsic() which accepts a
variable number of arguments to pass
the scale parameter
* update langref
- added case to test/compile_errors.zig given floats
- explain upstream bug in llvm.smul.fix.sat and link to #9643 in langref and commented out test cases
* sat-arithmetic: skip mul tests if arch == .wasm32 because ci is erroring with 'LLVM ERROR: Unable to expand fixed point multiplication' when compiling for wasm32
While the SysV ABI is not that complicated, LLVM does not allow us
direct access to enforce it. By mimicking the IR generated by clang,
we can trick LLVM into doing the right thing. This involves two main
additions:
1. `AGG` ABI class
This is not part of the spec, but since we have to track class per
eightbyte and not per struct, the current enum is not enough. I
considered adding multiple classes like: `INTEGER_INTEGER`,
`INTEGER_SSE`, `SSE_INTEGER`. However, all of those cases would trigger
the same code path so it's simpler to collapse into one. This class is
only used on SysV.
2. LLVM C ABI type
Clang uses different types in C ABI function signatures than the
original structs passed in, and does conversion. For example, this
struct: `{ i8, i8, float }` would use `{ i16, float }` at ABI boundaries.
When passed as an argument, it is instead split into two arguments `i16`
and `float`. Therefore, for every struct that passes ABI boundaries we
need to keep track of its corresponding ABI type. Here are some more
examples:
```
| Struct | ABI equivalent |
| { i8, i8, i8, i8 } | i32 |
| { float, float } | double |
| { float, i32, i8 } | { float, i64 } |
```
Then, we must update function calls, returns, parameter lists and inits
to properly convert back and forth as needed.
@select(
comptime T: type,
pred: std.meta.Vector(len, bool),
a: std.meta.Vector(len, T),
b: std.meta.Vector(len, T)
) std.meta.Vector(len, T)
Constructs a vector from a & b, based on the values in the predicate vector. For indices where the predicate value is true, the corresponding
element from the a vector is selected, and otherwise from b.
