dawn-cmake/docs/tint/origin-trial-changes.md

Tint changes during Origin Trial

Changes for M111

New features

• The workgroupUniformLoad builtin function is now supported. tint:1780
• The diagnostic directive and @diagnostic attribute are now supported. tint:1809
  • The attribute is currently only supported on function declarations.

Breaking changes

• You may need to add parentheses to less-than or greater-than binary expressions that now parse as template lists. For example a(b<c, d>e) will need parentheses around b<c or d>e. tint:1810.
• Uniformity analysis failures are now an error tint:880
  • The derivative_uniformity diagnostic filter can be used to modify the severity if needed.

Deprecated Features

• The keyword to alias a type has been renamed from type to alias. tint:1812
• static_assert has been renamed to const_assert. tint:1807

Changes for M110

Breaking changes

• The textureSampleLevel() overload for texture_external has been removed. Use textureSampleBaseClampToEdge(). tint:1671

Deprecated Features

• The sig member of the return type of frexp() has been renamed to fract. tint:1757
• Calling a function with multiple pointer arguments that alias each other is now a warning, and will become an error in a future release. tint:1675

Changes for M109

Breaking changes

• textureDimensions(), textureNumLayers() and textureNumLevels() now return unsigned integers / vectors. tint:1526
• The @stage attribute has been removed. The short forms should be used instead (@vertex, @fragment, or @compute). tint:1503
• Module-scope let is now an error. Use module-scope const instead. tint:1580
• Reserved words are now an error instead of a deprecation. tint:1463
• You may no longer use pointer parameters in workgroup address space. tint:1721

New features

• Uniformity analysis failures are warnings again tint:1728
• You can now call texture builtins with a mix of signed and unsigned integer arguments. tint:1733

Changes for M108

New features

• textureSampleBaseClampToEdge() has been implemented. tint:1671

Deprecated Features

• The external_texture overload of textureSampleLevel() has been deprecated. Use textureSampleBaseClampToEdge() instead. tint:1671

Fixes

• Constant evaluation of type conversions where the value exceeds the limits of the target type have been fixed. tint:1707

Changes for M107

New features

• saturate() has been implemented. tint:1591

Breaking changes

• Uniformity analysis failures are now an error tint:880
• Indexing an array, vector or matrix with a compile-time expression that's out-of-bounds is now an error tint:1665

Changes for M106

New features

• array() constructor can now infer type and count. tint:1628
• static_assert statement has been added. tint:1625

Deprecated Features

• The list of reserved words has been sync'd to the WGSL specification. tint:1463

Changes for M105

New features

• Module-scope var<private> can now infer the storage type, like function-scope var. tint:1584
• The acosh, asinh, and atanh builtin functions are now supported tint:1465

Breaking changes

• The smoothStep() builtin has been removed (use smoothstep instead). tint:1483
• Module-scope let has been replaced with module-scope const. tint:1580
  • Note: Module-scope const does not support structure types. Use var<private> if you need a module-scope structure type.
• Struct members can no longer be separated with semicolons (use commas instead). tint:1475
• Single scalar matrix constructors have been removed. These were never part of the WGSL spec. tint:1597

Deprecated Features

• The @stage attribute has been deprecated. The short forms should be used instead (@vertex, @fragment, or @compute). tint:1503

Changes for M104

New features

• Tint now supports abstract-numerics, removing the need to always suffix unsigned integers with u tint:1504
• Parsing of @compute, @fragment and @vertex added.

Changes for M103

New features

• Produce warnings for when calling barriers, textureSample, and derivative builtins in non-uniform control flow tint:880
• Matrix identity constructors and constructors for a single scalar value are now supported tint:1545

Breaking changes

• Builtin atomicCompareExchangeWeak returns a struct instead of a vec2. tint:1185

Changes for M102

New Features

• Parentheses are no longer required around expressions for if and switch statements tint:1424
• Compound assignment statements are now supported. tint:1325
• Postfix increment and decrement statements are now supported. tint:1488
• The colon in case statements is now optional. tint:1485

Breaking changes

• Struct members are now separated by commas. tint:1475
• The @block attribute has been removed. tint:1324
• The @stride attribute has been removed. tint:1381
• Attributes using [[attribute]] syntax are no longer supported. tint:1382
• The elseif keyword is no longer supported. tint:1289

Deprecated Features

• The smoothStep() builtin has been renamed to smoothstep(). tint:1483

Changes for M101

New Features

• Tint now supports unicode identifiers. tint:1437

Breaking changes

• The isNan(), isInf(), isFinite(), and isNormal() builtins have been removed. tint:1312

Changes for M100

Breaking changes

• The @interpolate(flat) attribute must now be specified on integral user-defined IO. tint:1224
• The ignore() intrinsic has been removed. Use phoney-assignment instead: ignore(expr); -> _ = expr;.
• break statements in continuing blocks are now correctly validated.

New Features

• Module-scope declarations can now be declared in any order. tint:1266
• The override keyword and @id() attribute for pipeline-overridable constants are now supported, replacing the @override attribute. tint:1403

Changes for M99

Breaking changes

Obviously infinite loops (no condition, no break) are now a validation error.

Deprecated Features

The following features have been deprecated and will be removed in M102:

• The [[block]] attribute has been deprecated. tint:1324
• Attributes now use the @decoration syntax instead of the [[decoration]] syntax. tint:1382
• elseif has been replaced with else if. tint:1289
• The [[stride]] attribute has been deprecated. tint:1381

New Features

• Vector and matrix element type can now be inferred from constructor argument types. tint:1334
• Added builtins degrees() and radians() for converting between degrees and radians. tint:1329
• let arrays and matrices can now be dynamically indexed. tint:1352
• Storage and Uniform buffer types no longer have to be structures. tint:1372
• A struct declaration does not have to be followed by a semicolon. tint:1380

Fixes

• Fixed an issue where for-loops that contain array or structure constructors in the loop initializer statements, condition expressions or continuing statements could fail to compile. tint:1364

Changes for M98

Breaking Changes

• Taking the address of a vector component is no longer allowed.
• Module-scope declarations can no longer alias a builtin name. tint:1318
• It is now an error to call a function either directly or transitively, from a loop continuing block, that uses discard. tint:1302

Deprecated Features

• The isNan(), isInf(), isFinite() and isNormal() builtins has been deprecated and will be removed in M101. tint:1312

New Features

• New texture gather builtins: textureGather() and textureGatherCompare(). tint:1330
• Shadowing is now fully supported. tint:819
• The dot() builtin now supports integer vector types.
• Identifiers can now start with a single leading underscore. tint:1292
• Control flow analysis has been improved, and functions no longer need to return if the statement is unreachable. tint:1302
• Unreachable statements now produce a warning instead of an error, to allow WGSL code to be updated to the new analysis behavior. These warnings may become errors in the future gpuweb#2378

Fixes

• Fixed an issue where using a module-scoped let in a workgroup_size may result in a compilation error. tint:1320

Changes for M97

Breaking Changes

• Deprecated modf() and frexp() builtin overloads that take a pointer second parameter have been removed.
• Deprecated texture builtin functions that accepted a read access controlled storage texture have been removed.
• Storage textures must now only use the write access control.

Deprecated Features

• The ignore() builtin has been replaced with phony-assignment. gpuweb#2127

New Features

• any() and all() now support a bool parameter. These simply return the passed argument. tint:1253
• Call statements may now include functions that return a value (ignore() is no longer needed).
• The interpolate(flat) attribute can now be specified on integral user-defined IO. It will eventually become an error to define integral user-defined IO without this attribute.
• Matrix construction from scalar element values is now supported.

Fixes

• Swizzling of vec3 types in storage and uniform buffers has been fixed for Metal 1.x. tint:1249
• Calling a function that returns an unused value no longer produces an FXC compilation error. tint:1259
• abs() fixed for unsigned integers on SPIR-V backend

Changes for M95

New Features

• The size of an array can now be defined using a non-overridable module-scope constant
• The num_workgroups builtin is now supported.

Fixes

• Hex floats: now correctly errors when the magnitude is non-zero, and the exponent would cause overflow. tint:1150, tint:1166
• Identifiers beginning with an underscore are now correctly rejected. tint:1179