MslEmitter.h File Reference

Deterministic Metal Shading Language emission from a donner::gpu::shader IR module. More...

#include <string>
#include "donner/gpu/shader/IrModule.h"
#include "donner/gpu/shader/ShaderResult.h"

Include dependency graph for MslEmitter.h:

Namespaces
namespace	donner
	Top-level Donner namespace, which is split into different sub-namespaces such as donner::svg and donner::css.

Functions
ShaderResult< std::string >	donner::gpu::shader::EmitMsl (const IrModule &module)
	Emits deterministic MSL text for module (design 0053 "Original emitters").

Detailed Description

Deterministic Metal Shading Language emission from a donner::gpu::shader IR module.

Function Documentation

EmitMsl()

ShaderResult< std::string > donner::gpu::shader::EmitMsl

(

const IrModule &

module

)

Emits deterministic MSL text for module (design 0053 "Original emitters").

Follows the same determinism discipline as EmitWgsl: declaration-order emission with dependency-ordered struct definitions, two-space indentation, LF-only lines with no trailing whitespace, shortest-round-trip float formatting (C++-legal: a .0 is added when the shortest form has no decimal point or exponent, then f), and fully parenthesized subexpressions.

Mapping highlights:

• Types: f32 -> float, vecN<T> -> floatN/intN/uintN/boolN, mat4x4f -> float4x4, sized arrays -> C arrays, structs -> C++ structs. The MSL natural layout of every buffer-referenced struct is verified member-by-member against the WGSL layout engine (ComputeStructLayout); any divergence (for example MSL's 16-byte float3, or a uniform array whose WGSL stride was padded to 16) fails closed instead of emitting a silently mismatched layout.
• Bindings use the argument-table map in MslBindingMap.h. MSL has no module-scope resources, so every module binding becomes a parameter: entry points receive them with [[buffer]]/[[texture]]/[[sampler]] attributes, plain functions receive them as leading parameters in module declaration order, and user-call sites forward them. Storage buffers are device const pointers (read-only expressed via const; device rather than constant address space so buffer sizes are unconstrained), uniform buffers are constant T&.
• Entry points: the vertex stage takes a generated <name>_Input struct via [[stage_in]] (fields carry [[attribute(location)]]) plus [[instance_id]]; the fragment stage takes a generated input struct whose members carry [[position]] / [[user(locnN)]]. Outputs are generated structs with [[position]] / [[user(locnN)]] (vertex) or [[color(N)]] (fragment). Parameter names are aliased locally so IR references emit unchanged.
• Builtins: saturate/fract/fwidth/abs/min/max/clamp/sqrt/length/round map to the metal namespace functions (via using namespace metal;), select(f, t, c) maps to (c ? t : f), textureSample -> tex.sample(smp, uv), textureLoad -> tex.read(uint2(coords), uint(level)), textureDimensions -> uint2(tex.get_width(), tex.get_height()), and discard -> discard_fragment().

Parameters

module

Module to emit.