Generalize RET for vec logical and comparison ops

This is the eighth of several changes that fix problems with the
specification of the `vec` class.  An implementation that follows the
existing specification would not accept common code patterns and would
not pass the CTS.  None of the existing implementations actually follow
the existing specification.

This change clarifies the return type for the comparison and logical
operators.  All of these operators return a vec of integers, where the
size of the integer elements depends on the element types of the input
operands.  The previous wording only specified the return type for
certain `DataT` types, leaving other types unspecified.  Reword this in
a general way which applies to all `DataT` types.

These changes correspond to slide 27 of the presentation that was
discussed in the WG meetings.

adoc/chapters/programming_interface.adoc

@@ -18367,7 +18367,14 @@ vec<RET, NumElements> operatorOP(const vec& lhs, const vec& rhs)
 ----
    a@ Construct a new instance of the SYCL [code]#vec# class template with the same template parameters as [code]#lhs# [code]#vec# with each element of the new SYCL [code]#vec# instance the result of an element-wise [code]#OP# logical operation between each element of [code]#lhs# [code]#vec# and each element of the [code]#rhs# SYCL [code]#vec#.
 
-The [code]#DataT# template parameter of the constructed SYCL [code]#vec#, [code]#RET#, varies depending on the [code]#DataT# template parameter of this SYCL [code]#vec#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int8_t# or [code]#uint8_t# [code]#RET# must be [code]#int8_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int16_t#, [code]#uint16_t# or [code]#half# [code]#RET# must be [code]#int16_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int32_t#, [code]#uint32_t# or [code]#float# [code]#RET# must be [code]#int32_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int64_t#, [code]#uint64_t# or [code]#double# [code]#RET# must be [code]#int64_t#.
+The element type of the returned [code]#vec#, [code]#RET#, varies depending on
+the size of the [code]#DataT# template parameter of the input [code]#vec#.
+If [code]#sizeof(DataT)# is 1, [code]#RET# is [code]#int8_t#.
+If [code]#sizeof(DataT)# is 2, [code]#RET# is [code]#int16_t#.
+If [code]#sizeof(DataT)# is 4, [code]#RET# is [code]#int32_t#.
+If [code]#sizeof(DataT)# is 8, [code]#RET# is [code]#int64_t#.
+If [code]#sizeof(DataT)# is any other value, [code]#RET# is an implementation
+defined integer type.
 
 Where [code]#OP# is: [code]#&&#, [code]#||#.
 
@@ -18378,7 +18385,14 @@ vec<RET, NumElements> operatorOP(const vec& lhs, const DataT& rhs)
 ----
    a@ Construct a new instance of the SYCL [code]#vec# class template with the same template parameters as this SYCL [code]#vec# with each element of the new SYCL [code]#vec# instance the result of an element-wise [code]#OP# logical operation between each element of [code]#lhs# [code]#vec# and the [code]#rhs# scalar.
 
-The [code]#DataT# template parameter of the constructed SYCL [code]#vec#, [code]#RET#, varies depending on the [code]#DataT# template parameter of this SYCL [code]#vec#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int8_t# or [code]#uint8_t# [code]#RET# must be [code]#int8_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int16_t#, [code]#uint16_t# or [code]#half# [code]#RET# must be [code]#int16_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int32_t#, [code]#uint32_t# or [code]#float# [code]#RET# must be [code]#int32_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int64_t#, [code]#uint64_t# or [code]#double# [code]#RET# must be [code]#uint64_t#.
+The element type of the returned [code]#vec#, [code]#RET#, varies depending on
+the size of the [code]#DataT# template parameter of the input [code]#vec#.
+If [code]#sizeof(DataT)# is 1, [code]#RET# is [code]#int8_t#.
+If [code]#sizeof(DataT)# is 2, [code]#RET# is [code]#int16_t#.
+If [code]#sizeof(DataT)# is 4, [code]#RET# is [code]#int32_t#.
+If [code]#sizeof(DataT)# is 8, [code]#RET# is [code]#int64_t#.
+If [code]#sizeof(DataT)# is any other value, [code]#RET# is an implementation
+defined integer type.
 
 Where [code]#OP# is: [code]#&&#, [code]#||#.
 
@@ -18392,7 +18406,14 @@ the same template parameters as the [code]#rhs# SYCL [code]#vec#
 with each element of the new SYCL [code]#vec# instance the result of
 an element-wise [code]#OP# logical operation between the [code]#lhs# scalar and each element of the [code]#rhs# SYCL [code]#vec#.
 
-The [code]#DataT# template parameter of the constructed SYCL [code]#vec#, [code]#RET#, varies depending on the [code]#DataT# template parameter of this SYCL [code]#vec#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int8_t# or [code]#uint8_t# [code]#RET# must be [code]#int8_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int16_t#, [code]#uint16_t# or [code]#half# [code]#RET# must be [code]#int16_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int32_t#, [code]#uint32_t# or [code]#float# [code]#RET# must be [code]#int32_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int64_t#, [code]#uint64_t# or [code]#double# [code]#RET# must be [code]#int64_t#.
+The element type of the returned [code]#vec#, [code]#RET#, varies depending on
+the size of the [code]#DataT# template parameter of the input [code]#vec#.
+If [code]#sizeof(DataT)# is 1, [code]#RET# is [code]#int8_t#.
+If [code]#sizeof(DataT)# is 2, [code]#RET# is [code]#int16_t#.
+If [code]#sizeof(DataT)# is 4, [code]#RET# is [code]#int32_t#.
+If [code]#sizeof(DataT)# is 8, [code]#RET# is [code]#int64_t#.
+If [code]#sizeof(DataT)# is any other value, [code]#RET# is an implementation
+defined integer type.
 
 Where [code]#OP# is: [code]#&&#, [code]#||#.
 
@@ -18403,7 +18424,14 @@ vec<RET, NumElements> operatorOP(const vec& lhs, const vec& rhs)
 ----
    a@ Construct a new instance of the SYCL [code]#vec# class template with the element type [code]#RET# with each element of the new SYCL [code]#vec# instance the result of an element-wise [code]#OP# relational operation between each element of [code]#lhs# [code]#vec# and each element of the [code]#rhs# SYCL [code]#vec#. Each element of the SYCL [code]#vec# that is returned must be [code]#-1# if the operation results in [code]#true# and [code]#0# if the operation results in [code]#false#.  The [code]#==#, [code]#<#, [code]#>#, [code]#+<=+# and [code]#>=# operations result in [code]#false# if either the [code]#lhs# element or the [code]#rhs# element is a NaN.  The [code]#!=# operation results in [code]#true# if either the [code]#lhs# element or the [code]#rhs# element is a NaN.
 
-The [code]#DataT# template parameter of the constructed SYCL [code]#vec#, [code]#RET#, varies depending on the [code]#DataT# template parameter of this SYCL [code]#vec#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int8_t# or [code]#uint8_t# [code]#RET# must be [code]#int8_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int16_t#, [code]#uint16_t# or [code]#half# [code]#RET# must be [code]#int16_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int32_t#, [code]#uint32_t# or [code]#float# [code]#RET# must be [code]#int32_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int64_t#, [code]#uint64_t# or [code]#double# [code]#RET# must be [code]#uint64_t#.
+The element type of the returned [code]#vec#, [code]#RET#, varies depending on
+the size of the [code]#DataT# template parameter of the input [code]#vec#.
+If [code]#sizeof(DataT)# is 1, [code]#RET# is [code]#int8_t#.
+If [code]#sizeof(DataT)# is 2, [code]#RET# is [code]#int16_t#.
+If [code]#sizeof(DataT)# is 4, [code]#RET# is [code]#int32_t#.
+If [code]#sizeof(DataT)# is 8, [code]#RET# is [code]#int64_t#.
+If [code]#sizeof(DataT)# is any other value, [code]#RET# is an implementation
+defined integer type.
 
 Where [code]#OP# is: [code]#==#, [code]#!=#, [code]#<#, [code]#>#, [code]#+<=+#, [code]#>=#.
 
@@ -18414,7 +18442,14 @@ vec<RET, NumElements> operatorOP(const vec& lhs, const DataT& rhs)
 ----
    a@ Construct a new instance of the SYCL [code]#vec# class template with the [code]#DataT# parameter of [code]#RET# with each element of the new SYCL [code]#vec# instance the result of an element-wise [code]#OP# relational operation between each element of [code]#lhs# [code]#vec# and the [code]#rhs# scalar. Each element of the SYCL [code]#vec# that is returned must be [code]#-1# if the operation results in [code]#true# and [code]#0# if the operation results in [code]#false#.  The [code]#==#, [code]#<#, [code]#>#, [code]#+<=+# and [code]#>=# operations result in [code]#false# if either the [code]#lhs# element or the [code]#rhs# is a NaN.  The [code]#!=# operation results in [code]#true# if either the [code]#lhs# element or the [code]#rhs# is a NaN.
 
-The [code]#DataT# template parameter of the constructed SYCL [code]#vec#, [code]#RET#, varies depending on the [code]#DataT# template parameter of this SYCL [code]#vec#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int8_t# or [code]#uint8_t# [code]#RET# must be [code]#int8_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int16_t#, [code]#uint16_t# or [code]#half# [code]#RET# must be [code]#int16_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int32_t#, [code]#uint32_t# or [code]#float# [code]#RET# must be [code]#int32_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int64_t#, [code]#uint64_t# or [code]#double# [code]#RET# must be [code]#uint64_t#.
+The element type of the returned [code]#vec#, [code]#RET#, varies depending on
+the size of the [code]#DataT# template parameter of the input [code]#vec#.
+If [code]#sizeof(DataT)# is 1, [code]#RET# is [code]#int8_t#.
+If [code]#sizeof(DataT)# is 2, [code]#RET# is [code]#int16_t#.
+If [code]#sizeof(DataT)# is 4, [code]#RET# is [code]#int32_t#.
+If [code]#sizeof(DataT)# is 8, [code]#RET# is [code]#int64_t#.
+If [code]#sizeof(DataT)# is any other value, [code]#RET# is an implementation
+defined integer type.
 
 Where [code]#OP# is: [code]#==#, [code]#!=#, [code]#<#, [code]#>#, [code]#+<=+#, [code]#>=#.
 
@@ -18436,16 +18471,14 @@ vec<RET, NumElements> operatorOP(const DataT& lhs, const vec& rhs)
       operation results in [code]#true# if either the [code]#lhs# or the
       [code]#rhs# element is a NaN.
 
-The [code]#DataT# template parameter of the constructed SYCL
-[code]#vec#, [code]#RET#, varies depending on the [code]#DataT# template parameter of this SYCL [code]#vec#. For a SYCL
-[code]#vec# with [code]#DataT# of type [code]#int8_t# or
-[code]#uint8_t# [code]#RET# must be [code]#int8_t#. For a
-SYCL [code]#vec# with [code]#DataT# of type [code]#int16_t#, [code]#uint16_t# or [code]#half# [code]#RET#
-must be [code]#int16_t#. For a SYCL [code]#vec# with
-[code]#DataT# of type [code]#int32_t#, [code]#uint32_t# or
-[code]#float# [code]#RET# must be [code]#int32_t#. For a
-SYCL [code]#vec# with [code]#DataT# of type [code]#int64_t#, [code]#uint64_t# or [code]#double# [code]#RET#
-must be [code]#int64_t#.
+The element type of the returned [code]#vec#, [code]#RET#, varies depending on
+the size of the [code]#DataT# template parameter of the input [code]#vec#.
+If [code]#sizeof(DataT)# is 1, [code]#RET# is [code]#int8_t#.
+If [code]#sizeof(DataT)# is 2, [code]#RET# is [code]#int16_t#.
+If [code]#sizeof(DataT)# is 4, [code]#RET# is [code]#int32_t#.
+If [code]#sizeof(DataT)# is 8, [code]#RET# is [code]#int64_t#.
+If [code]#sizeof(DataT)# is any other value, [code]#RET# is an implementation
+defined integer type.
 
 Where [code]#OP# is: [code]#==#, [code]#!=#, [code]#<#, [code]#>#, [code]#+<=+#, [code]#>=#.
 
@@ -18465,7 +18498,14 @@ vec<RET, NumElements> operator!(const vec& v)
 ----
    a@ Construct a new instance of the SYCL [code]#vec# class template with the same template parameters as [code]#v# [code]#vec# with each element of the new SYCL [code]#vec# instance the result of an element-wise logical NOT operation on each element of [code]#v# [code]#vec#. Each element of the SYCL [code]#vec# that is returned must be [code]#-1# if the operation results in [code]#true# and [code]#0# if the operation results in [code]#false# or this SYCL [code]#vec# is a NaN.
 
-The [code]#DataT# template parameter of the constructed SYCL [code]#vec#, [code]#RET#, varies depending on the [code]#DataT# template parameter of this SYCL [code]#vec#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int8_t# or [code]#uint8_t# [code]#RET# must be [code]#int8_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int16_t#, [code]#uint16_t# or [code]#half# [code]#RET# must be [code]#int16_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int32_t#, [code]#uint32_t# or [code]#float# [code]#RET# must be [code]#int32_t#. For a SYCL [code]#vec# with [code]#DataT# of type [code]#int64_t#, [code]#uint64_t# or [code]#double# [code]#RET# must be [code]#int64_t#.
+The element type of the returned [code]#vec#, [code]#RET#, varies depending on
+the size of the [code]#DataT# template parameter of the input [code]#vec#.
+If [code]#sizeof(DataT)# is 1, [code]#RET# is [code]#int8_t#.
+If [code]#sizeof(DataT)# is 2, [code]#RET# is [code]#int16_t#.
+If [code]#sizeof(DataT)# is 4, [code]#RET# is [code]#int32_t#.
+If [code]#sizeof(DataT)# is 8, [code]#RET# is [code]#int64_t#.
+If [code]#sizeof(DataT)# is any other value, [code]#RET# is an implementation
+defined integer type.
 
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