It seems that some implementations may have problems with these right now,
like Intel and Rusticl. In theory, these attributes should be superficial
on the pointer type, as alignment guarantees are also added via the
alignment option of the OpLoad and OpStore instructions. Therefore, get rid
of them for now.
Entry points need to be attributed with a complete list of
global variables that they use. To that end, the global dependencies
mechanism is extended to also allow functions - when flushing the
module, the list of dependencies is examined to generate this
list of global variable result-ids.
SPIR-V cannot represent function pointers without extensions
that no vendor implements. For the time being, generate a test
kernel for each error, so that we can at least run SOME tests.
In the future we may be able to emulate function pointers in some
way, but that is not today.
SPIR-V globals must be emitted in order, so that any
declaration precedes usage. Zig, however, generates globals in
random order. To this end we keep for each global a list of
dependencies and perform a topological sort when flushing the
module.
Lowering constants is currently not really compatible with unions. In
this commit, constant lowering is drastically overhauled: instead of
playing nice and generating SPIR-V constant representations for everything
directly, we're just going to treat globals as an untyped bag of bytes (
or rather, SPIR-V 32-bit words), which we cast to the desired type at
usage. This is similar to how Rust generates constants in its LLVm backend.
Similar to function locals, taking the address of a global that does
not have an explicit address space assigned to it should result
in a generic pointer, not a global pointer. Also similar to function
locals, they cannot be generated into the generic storage class, and
so are generated into the global storage class and then cast to a
generic pointer, using OpSpecConstantOp. Note that using
OpSpecConstantOp results is only allowed by a hand full of other
OpSpecConstant instructions - which is why we generate constant
structs using OpSpecConstantComposite: These may use OpVariable
and OpSpecConstantOp results, while OpConstantComposite may not.
This cloneAir/cloneLiveness idea used to ignore Zig's internals
has proven buggy. Instead, just generate the code directly from
updateFunc and updateDecl as the other backends do, but pretend
that Zig is not an incremental compiler. The SPIR-V backend will
for the time being not support this.
Bools have a different immediate representation and memory
representation - which means that they must be converted every time
a bool is loaded from or stored into memory.
Taking the address of a local variable should result in a generic
pointer - too much code breaks if we do not do this. We cannot
lower locals into the generic storage class directly though, so
instead, lower the variables into the Function storage class
implicitly, and convert the pointer to a generic pointer.
Also Correct OpInboundsAccessChain generation (we only need
the one index).
There are two main ways in which a value can be stored: "Direct", as it
will be operated on as an immediate value, and "indirect", as it is stored
in memory. Some types need a different representation here: Bools, for
example, are opaque in SPIR-V, and so these need to have a different
representation in memory. The bool operations are not easily interchangable
with integer operations, though, so they need to be OpTypeBool as
immediate value.
Previously they were strong aliases, but as these types are used quite
intermittendly it resulted in a lot of toRef() calls. Removing them
improves readability a bit.
- Adds the Int8. Int16, Int64 and GenericPointer capabilities.
TODO: This should integrate with the feature system.
- Default some struct fields of SPIR-V types so that we dont
need to type them all the time.
- Store struct field name's in SPIR-V types, and generate the
OpMemberName decoration if they are non-null.
- Also add the field names to the actual SPIR-V types.
- Generate OpName for functions.
Implements the div-family and intcast AIR instructions, and starts
implementing a mechanism for masking the value of 'strange' integers
before they are used in an operation that does not hold under modulo.
Implements lowering for the add_with_overflow AIR instructions. Also implements
a helper function, simpleStructType, to quickly generate a SPIR-V structure type
without having to do the whole allocation dance.
When a result of a pure instruction is not used, it also does not need to
be generated. The other backends already implement these checks, they were
ignored in SPIR-V up until now. New instructions added in the future should
have these be implemented from the start.
Implements type lowering for arrays and structs, and implements instruction
lowering for bitcast and call. Bitcast currently naively maps to the OpBitcast
instruction - this is only valid for some primitive types, and should be
improved to work with composites.
In practice there are only a few variations of these types allowed, so it
kind-of makes sense to write them all out. Because the types are hashed this
does not actually save all that many bytes in the long run, though. Perhaps
some of these types should be pre-registered?
This allows the Zig calling convention and makes way for a Kernel
calling convention in the future. Any future checks on calling
conventions should be placed in Sema.zig.
spirv: introduce SpvModule.Fn to generate function code into
spirv: assembler error message setup
spirv: runtime spec info
spirv: inline assembly tokenizer
spirv: inline assembly lhs result/opcode parsing
spirv: forgot to fmt
spirv: tokenize opcodes and assigned result-ids
spirv: operand parsing setup
spirv: assembler string literals
spirv: assembler integer literals
spirv: assembler value enums
spirv: assembler bit masks
spirv: update assembler to new asm air format
spirv: target 1.5 for now
Current vulkan sdk version (1.3.204) ships spirv tools targetting 1.5,
and so these do not work with binaries targetting 1.6 yet. In the
future, this version number should be decided by the target.
spirv: store operands in flat arraylist.
Instead of having dedicated Operand variants for variadic operands,
just flatten them and store them in the normal inst.operands list.
This is a little simpler, but is not easily decodable in the operand
data representation.
spirv: parse variadic assembly operands
spirv: improve assembler result-id tokenization
spirv: begin instruction processing
spirv: only remove decl if it was actually allocated
spirv: work around weird miscompilation
Seems like there are problems with switch in anonymous struct literals.
spirv: begin resolving some types in assembler
spirv: improve instruction processing
spirv: rename some types + process OpTypeInt
spirv: process OpTypeVector
spirv: process OpTypeMatrix and OpTypeSampler
spirv: add opcode class to spec, remove @exclude'd instructions
spirv: process more type instructions
spirv: OpTypeFunction
spirv: OpTypeOpaque
spirv: parse LiteralContextDependentNumber operands
spirv: emit assembly instruction into right section
spirv: parse OpPhi parameters
spirv: inline assembly inputs
spirv: also copy air types
spirv: inline assembly outputs
spirv: spir-v address spaces
spirv: basic vector constants/types and shuffle
spirv: assembler OpTypeImage
spirv: some stuff
spirv: remove spirv address spaces for now
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);
```
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.
