ignored.
+.. _threadsyncopcodes:
+
+Inter-thread synchronization opcodes
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+These opcodes are intended for communication between threads running
+within the same compute grid. For now they're only valid in compute
+programs.
+
+.. opcode:: MFENCE - Memory fence
+
+ Syntax: ``MFENCE resource``
+
+ Example: ``MFENCE RES[0]``
+
+ This opcode forces strong ordering between any memory access
+ operations that affect the specified resource. This means that
+ previous loads and stores (and only those) will be performed and
+ visible to other threads before the program execution continues.
+
+
+.. opcode:: LFENCE - Load memory fence
+
+ Syntax: ``LFENCE resource``
+
+ Example: ``LFENCE RES[0]``
+
+ Similar to MFENCE, but it only affects the ordering of memory loads.
+
+
+.. opcode:: SFENCE - Store memory fence
+
+ Syntax: ``SFENCE resource``
+
+ Example: ``SFENCE RES[0]``
+
+ Similar to MFENCE, but it only affects the ordering of memory stores.
+
+
+.. opcode:: BARRIER - Thread group barrier
+
+ ``BARRIER``
+
+ This opcode suspends the execution of the current thread until all
+ the remaining threads in the working group reach the same point of
+ the program. Results are unspecified if any of the remaining
+ threads terminates or never reaches an executed BARRIER instruction.
+
+
+.. _atomopcodes:
+
+Atomic opcodes
+^^^^^^^^^^^^^^
+
+These opcodes provide atomic variants of some common arithmetic and
+logical operations. In this context atomicity means that another
+concurrent memory access operation that affects the same memory
+location is guaranteed to be performed strictly before or after the
+entire execution of the atomic operation.
+
+For the moment they're only valid in compute programs.
+
+.. opcode:: ATOMUADD - Atomic integer addition
+
+ Syntax: ``ATOMUADD dst, resource, offset, src``
+
+ Example: ``ATOMUADD TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = dst_i + src_i
+
+
+.. opcode:: ATOMXCHG - Atomic exchange
+
+ Syntax: ``ATOMXCHG dst, resource, offset, src``
+
+ Example: ``ATOMXCHG TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = src_i
+
+
+.. opcode:: ATOMCAS - Atomic compare-and-exchange
+
+ Syntax: ``ATOMCAS dst, resource, offset, cmp, src``
+
+ Example: ``ATOMCAS TEMP[0], RES[0], TEMP[1], TEMP[2], TEMP[3]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = (dst_i == cmp_i ? src_i : dst_i)
+
+
+.. opcode:: ATOMAND - Atomic bitwise And
+
+ Syntax: ``ATOMAND dst, resource, offset, src``
+
+ Example: ``ATOMAND TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = dst_i \& src_i
+
+
+.. opcode:: ATOMOR - Atomic bitwise Or
+
+ Syntax: ``ATOMOR dst, resource, offset, src``
+
+ Example: ``ATOMOR TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = dst_i | src_i
+
+
+.. opcode:: ATOMXOR - Atomic bitwise Xor
+
+ Syntax: ``ATOMXOR dst, resource, offset, src``
+
+ Example: ``ATOMXOR TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = dst_i \oplus src_i
+
+
+.. opcode:: ATOMUMIN - Atomic unsigned minimum
+
+ Syntax: ``ATOMUMIN dst, resource, offset, src``
+
+ Example: ``ATOMUMIN TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = (dst_i < src_i ? dst_i : src_i)
+
+
+.. opcode:: ATOMUMAX - Atomic unsigned maximum
+
+ Syntax: ``ATOMUMAX dst, resource, offset, src``
+
+ Example: ``ATOMUMAX TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = (dst_i > src_i ? dst_i : src_i)
+
+
+.. opcode:: ATOMIMIN - Atomic signed minimum
+
+ Syntax: ``ATOMIMIN dst, resource, offset, src``
+
+ Example: ``ATOMIMIN TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = (dst_i < src_i ? dst_i : src_i)
+
+
+.. opcode:: ATOMIMAX - Atomic signed maximum
+
+ Syntax: ``ATOMIMAX dst, resource, offset, src``
+
+ Example: ``ATOMIMAX TEMP[0], RES[0], TEMP[1], TEMP[2]``
+
+ The following operation is performed atomically on each component:
+
+.. math::
+
+ dst_i = resource[offset]_i
+
+ resource[offset]_i = (dst_i > src_i ? dst_i : src_i)
+
+
+
Explanation of symbols used
------------------------------
UsageMask field specifies which of the register components can be accessed
and is one of TGSI_WRITEMASK.
+The Local flag specifies that a given value isn't intended for
+subroutine parameter passing and, as a result, the implementation
+isn't required to give any guarantees of it being preserved across
+subroutine boundaries. As it's merely a compiler hint, the
+implementation is free to ignore it.
+
If Dimension flag is set to 1, a Declaration Dimension token follows.
If Semantic flag is set to 1, a Declaration Semantic token follows.
projects / mesa.git / blobdiff