Merge branch 'main' into khr_addrspace_cast

adoc/chapters/architecture.adoc

@@ -1389,7 +1389,7 @@ implementation-defined.
 
 
 [[sec:coordination]]
-=== Coordination and Synchronization
+=== Coordination and synchronization
 
 Coordination between the host and any devices can be expressed in the host SYCL
 application using calls into the SYCL runtime.
@@ -1403,7 +1403,7 @@ Such functions can be used to ensure that the host and any devices do not access
 data concurrently, and/or to reason about the ordering of operations across the
 host and any devices.
 
-==== Host-Device Coordination
+==== Host-device coordination
 
 The following operations can be used to coordinate host and device(s):
 
@@ -1456,7 +1456,7 @@ So it is up to the programmer to use a member function to wait for completion in
 some cases if this does not fit the goal.
 See <<sec:managing-object-lifetimes>> for more information on object life time.
 
-==== Work-item Coordination
+==== Work-item coordination
 
 A <<group-barrier>> provides a mechanism to coordinate all work-items in the
 same group.

adoc/chapters/device_compiler.adoc

@@ -205,6 +205,16 @@ Amongst other things, this restriction makes it illegal for a
     implementation defines the [code]#SYCL_EXTERNAL# macro as described in
     <<subsec:syclexternal>>.
 
+Inside a <<discarded-statement>> or in the case of a
+<<manifestly-constant-evaluated>>, any code accepted by the C++ standard in this
+case is also accepted in a SYCL <<device-function>>.
+
+[NOTE]
+====
+The restriction waiver in <<discarded-statement>> or
+<<manifestly-constant-evaluated>> allows any kind of meta-programming in a
+<<device-function>>.
+====
 
 [[subsec:scalartypes]]
 == Built-in scalar data types
@@ -377,8 +387,17 @@ in <<sec:backends>> must be defined by all conformant implementations.
 
 A number of kernel features defined by this SYCL specification are optional;
 they may be supported on some devices but not on other devices.
+
+As stated in <<sec:language.restrictions.kernels>>, the restrictions for
+optional kernel features do not apply to discarded statements or to manifestly
+constant-evaluated expressions or conversions in device code.
+Device code may use optional features in <<discarded-statement>> or
+<<manifestly-constant-evaluated>> even if the device does not support the
+optional feature.
+
 As described in <<sec:device-aspects>>, an application can test whether a device
-supports these features by testing whether the device has an associated aspect.
+supports an optional feature by testing whether the device has an associated
+aspect.
 The following aspects are those that correspond to optional kernel features:
 
   * [code]#fp16#

adoc/chapters/glossary.adoc

@@ -188,6 +188,12 @@ For the full description please refer to <<subsec:buffers>>.
     One of the device with the highest non-negative value is selected.
     See <<sec:device-selector>> for more details.
 
+[[discarded-statement]]discarded statement::
+    ISO C++ +[stmt.if]+ describes a discarded statement as the branch statement
+    of an [code]#if constexpr# which is not instantiated because of the boolean
+    condition.
+    For more context, see <<sec:language.restrictions.kernels>>.
+
 [[event]]event::
     A SYCL object that represents the status of an operation that is being
     executed by the SYCL runtime.
@@ -339,6 +345,14 @@ For the full description please refer to <<subsec:buffers>>.
     Local memory is a memory region associated with a <<work-group>> and
     accessible only by <<work-item,work-items>> in that <<work-group>>.
 
+[[manifestly-constant-evaluated]]manifestly constant-evaluated expression or conversion::
+    ISO C++ +[expr.const]+ describes manifestly constant-evaluated expression or
+    conversion like constant expressions, condition of an +if constexpr+, an
+    immediate invocation, used in template parameters, in constant
+    initialization, etc.
+    This is evaluated at compile-time by the compiler.
+    For more context, see <<sec:language.restrictions.kernels>>.
+
 [[mem-fence]]mem-fence::
     A memory fence provides control over re-ordering of memory load and store
     operations when coupled with an atomic operation.
@@ -353,7 +367,6 @@ For the full description please refer to <<subsec:buffers>>.
     A <<specialization-constant>> in a device image whose value can be used by
     an online compiler as an immediate value during the compilation.
 
-
 [[nd-item]]nd-item::
     A unique identifier representing a single <<work-item>> and <<work-group>>
     within the index space of a SYCL kernel execution.

adoc/chapters/programming_interface.adoc

@@ -9933,7 +9933,6 @@ For interoperability with the <<backend>>, users should rely on types exposed by
 the decorated version.
 If the value of [code]#access::decorated# is [code]#access::decorated::legacy#,
 the 1.2.1 interface is exposed.
-This interface is deprecated.
 
 The template traits [code]#remove_decoration# and type alias
 [code]#remove_decoration_t# retrieve the non-decorated pointer or reference from
@@ -10136,7 +10135,7 @@ operator=(const multi_ptr<value_type, AS, IsDecorated>&)
 ----
    a@ Available only when: [code]#(Space == access::address_space::generic_space && AS != access::address_space::constant_space)#.
 
-Assigns the value of the left hand side [code]#multi_ptr# into the [code]#generic_ptr#.
+Assigns the value of the right hand side [code]#multi_ptr# into the [code]#generic_ptr#.
 
 a@
 [source]
@@ -10149,7 +10148,7 @@ operator=(multi_ptr<value_type, AS, IsDecorated>&&)
    a@ Available only when:
       [code]#(Space == access::address_space::generic_space && AS != access::address_space::constant_space)#.
 
-Move the value of the left hand side [code]#multi_ptr# into the [code]#generic_ptr#.
+Move the value of the right hand side [code]#multi_ptr# into the [code]#generic_ptr#.
 
 a@
 [source]
@@ -10642,10 +10641,6 @@ below.
 include::{header_dir}/pointer.h[lines=4..-1]
 ----
 
-Note that using [code]#global_ptr#, [code]#local_ptr#, [code]#constant_ptr# or
-[code]#private_ptr# without specifying the decoration is deprecated.
-The default argument is provided for compatibility with 1.2.1.
-
 
 [[subsec:samplers]]
 === Image samplers
@@ -13892,9 +13887,10 @@ property::reduction::initialize_to_identity
       identity value passed to the reduction interface, or to the identity
       value determined by the [code]#known_identity# trait if no identity value
       was specified. If no identity value was specified and an identity value
-      cannot be determined by the [code]#known_identity# trait, the compiler
-      must raise a diagnostic. When this property is set, the original value of
-      the reduction variable is not included in the reduction.
+      cannot be determined by the [code]#known_identity# trait, the
+      implementation must throw an [code]#exception# with the
+      [code]#errc::invalid# error code. When this property is set, the original
+      value of the reduction variable is not included in the reduction.
 
 |====
 

adoc/chapters/what_changed.adoc

@@ -385,7 +385,6 @@ Changes in [code]#multi_ptr# interface:
      Returned pointer and reference are not annotated by an address space;
   ** interface exposing decorated types.
      Returned pointer and reference are annotated by an address space;
-  ** legacy 1.2.1 interface (deprecated).
   * deprecation of the 1.2.1 interface;
   * deprecation of [code]#constant_ptr#;
   * [code]#global_ptr#, [code]#local_ptr# and [code]#private_ptr# alias take the
@@ -468,4 +467,8 @@ parameters did not clearly specify which accessor's size determines the amount
 of memory that is copied.
 The spec now clarifies that the [code]#src# accessor's size is used.
 
+Any code considered as a <<discarded-statement>> or as a
+<<manifestly-constant-evaluated>> by the C++ standard is now also accepted in
+SYCL device function.
+
 // %%%%%%%%%%%%%%%%%%%%%%%%%%%% end what_changed %%%%%%%%%%%%%%%%%%%%%%%%%%%%

adoc/config/rouge/lib/rouge/lexers/sycl.rb

@@ -312,6 +312,7 @@ class Sycl < Cpp
         context_bound
         cpu_selector
         decorated_constant_ptr
+        decorated_generic_ptr
         decorated_global_ptr
         decorated_local_ptr
         decorated_private_ptr

adoc/extensions/index.adoc

@@ -7,10 +7,9 @@ working group.
 These extensions may be promoted to core features in future versions of the SYCL
 specification, but their design is subject to change.
 
-(There are currently no extensions in this appendix.)
-
 // leveloffset=2 allows extensions to be written as standalone documents
 // include::sycl_khr_extension_name.adoc[leveloffset=2]
 
+include::sycl_khr_default_context.adoc[leveloffset=2]
 include::sycl_khr_static_addrspace_cast.adoc[leveloffset=2]
 include::sycl_khr_dynamic_addrspace_cast.adoc[leveloffset=2]

adoc/extensions/sycl_khr_default_context.adoc

@@ -0,0 +1,57 @@
+[[sec:khr-default-context]]
+= SYCL_KHR_DEFAULT_CONTEXT
+
+When a [code]#queue# object is constructed without passing an explicit
+[code]#context# object, the queue uses the platform's default context.
+This extension adds a new query function to retrieve this default context from a
+[code]#platform# object.
+
+[[sec:khr-default-context-dependencies]]
+== Dependencies
+
+This extension has no dependencies on other extensions.
+
+[[sec:khr-default-context-feature-test]]
+== Feature test macro
+
+An implementation supporting this extension must predefine the macro
+[code]#SYCL_KHR_DEFAULT_CONTEXT# to one of the values defined in the table
+below.
+
+[%header,cols="1,5"]
+|===
+|Value
+|Description
+
+|1
+|Initial version of this extension.
+|===
+
+[[sec:khr-default-context-platform]]
+== Extensions to the platform class
+
+This extension adds the following new member functions to the [code]#platform#
+class.
+
+[source,role=synopsis,id=api:khr-default-context-platform]
+----
+namespace sycl {
+class platform {
+  context khr_get_default_context() const;
+  // ...
+};
+}
+----
+
+[[sec:khr-default-context-platform-member-funcs]]
+=== Member functions
+
+.[apidef]#platform::khr_get_default_context#
+[source,role=synopsis,id=api:platform-khr-get-default-context]
+----
+context khr_get_default_context() const
+----
+
+_Returns:_ A copy of the default context object for this platform.
+The default context contains all of the <<root-device, root devices>> that are
+associated with this platform.

adoc/headers/multipointer.h

@@ -15,7 +15,7 @@ enum class address_space : /* unspecified */ {
 enum class decorated : /* unspecified */ {
   no,
   yes,
-  legacy // Deprecated in SYCL 2020
+  legacy
 };
 
 } // namespace access

adoc/headers/multipointerlegacy.h

@@ -4,7 +4,6 @@
 namespace sycl {
 
 // Legacy interface, inherited from 1.2.1.
-// Deprecated.
 template <typename ElementType, access::address_space Space>
 class [[deprecated]] multi_ptr<ElementType, Space, access::decorated::legacy> {
  public:
@@ -162,7 +161,6 @@ class [[deprecated]] multi_ptr<ElementType, Space, access::decorated::legacy> {
 };
 
 // Legacy interface, inherited from 1.2.1.
-// Deprecated.
 // Specialization of multi_ptr for void and const void
 // VoidType can be either void or const void
 template <access::address_space Space>

adoc/headers/pointer.h

@@ -30,6 +30,11 @@ template <typename ElementType,
 using private_ptr =
     multi_ptr<ElementType, access::address_space::private_space, IsDecorated>;
 
+template <typename ElementType,
+          access::decorated IsDecorated = access::decorated::legacy>
+using generic_ptr =
+    multi_ptr<ElementType, access::address_space::generic_space, IsDecorated>;
+
 // Template specialization aliases for different pointer address spaces.
 // The interface exposes non-decorated pointer while keeping the
 // address space information internally.
@@ -48,6 +53,11 @@ using raw_private_ptr =
     multi_ptr<ElementType, access::address_space::private_space,
               access::decorated::no>;
 
+template <typename ElementType>
+using raw_generic_ptr =
+    multi_ptr<ElementType, access::address_space::generic_space,
+              access::decorated::no>;
+
 // Template specialization aliases for different pointer address spaces.
 // The interface exposes decorated pointer.
 
@@ -66,4 +76,9 @@ using decorated_private_ptr =
     multi_ptr<ElementType, access::address_space::private_space,
               access::decorated::yes>;
 
+template <typename ElementType>
+using decorated_generic_ptr =
+    multi_ptr<ElementType, access::address_space::generic_space,
+              access::decorated::yes>;
+
 } // namespace sycl

adoc/scripts/reflow.py

@@ -53,7 +53,7 @@
 # A single letter followed by a period, typically a middle initial.
 endInitial = re.compile(r'^[A-Z]\.$')
 # An abbreviation, which does not (usually) end a line.
-endAbbrev = re.compile(r'(e\.g|i\.e|c\.f|\bvs\b|\bco\b|\bltd\b|\bch\b)\.$', re.IGNORECASE)
+endAbbrev = re.compile(r'(e\.g|i\.e|\bvs\b|\bco\b|\bltd\b|\bch\b|\bcf\b)\.$', re.IGNORECASE)
 # A lower case word.  When "etc." is followed by this, it does not end a line.
 startsLowerCase = re.compile(r'\(?[a-z]')