Commit 6a6d8b6f authored by Dave Thaler's avatar Dave Thaler Committed by Alexei Starovoitov
Browse files

bpf, docs: Add table captions 

As suggested by Ines Robles in his IETF GENART review at
https://datatracker.ietf.org/doc/review-ietf-bpf-isa-02-genart-lc-robles-2024-05-16/



Signed-off-by: default avatarDave Thaler <dthaler1968@gmail.com>
Link: https://lore.kernel.org/r/20240524164618.18894-1-dthaler1968@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 4e1215d9

Documentation/bpf/standardization/instruction-set.rst

+102 −82
Original line number Diff line number Diff line
@@ -32,7 +32,7 @@ Types 
This document refers to integer types with the notation `SN` to specify

a type's signedness (`S`) and bit width (`N`), respectively.



.. table:: Meaning of signedness notation.

.. table:: Meaning of signedness notation



  ==== =========

  S    Meaning
@@ -41,7 +41,7 @@ a type's signedness (`S`) and bit width (`N`), respectively. 
  s    signed

  ==== =========



.. table:: Meaning of bit-width notation.

.. table:: Meaning of bit-width notation



  ===== =========

  N     Bit width
@@ -263,6 +263,8 @@ Instruction classes 


The three least significant bits of the 'opcode' field store the instruction class:



.. table:: Instruction class



  =====  =====  ===============================  ===================================

  class  value  description                      reference

  =====  =====  ===============================  ===================================
@@ -292,6 +294,8 @@ For arithmetic and jump instructions (``ALU``, ``ALU64``, ``JMP`` and 
**s (source)**

  the source operand location, which unless otherwise specified is one of:



  .. table:: Source operand location



  ======  =====  ==============================================

  source  value  description

  ======  =====  ==============================================
@@ -312,6 +316,8 @@ The 'code' field encodes the operation as below, where 'src' refers to the 
the source operand and 'dst' refers to the value of the destination

register.



.. table:: Arithmetic instructions



  =====  =====  =======  ==========================================================

  name   code   offset   description

  =====  =====  =======  ==========================================================
@@ -426,6 +432,8 @@ select what byte order the operation converts from or to. For 
``ALU64``, the 1-bit source operand field in the opcode is reserved

and MUST be set to 0.



.. table:: Byte swap instructions



  =====  ========  =====  =================================================

  class  source    value  description

  =====  ========  =====  =================================================
@@ -468,6 +476,8 @@ otherwise identical operations, and indicates the base64 conformance 
group unless otherwise specified.

The 'code' field encodes the operation as below:



.. table:: Jump instructions



  ========  =====  =======  =================================  ===================================================

  code      value  src_reg  description                        notes

  ========  =====  =======  =================================  ===================================================
@@ -559,6 +569,8 @@ For load and store instructions (``LD``, ``LDX``, ``ST``, and ``STX``), the 
**mode**

  The mode modifier is one of:



  .. table:: Mode modifier



    =============  =====  ====================================  =============

    mode modifier  value  description                           reference

    =============  =====  ====================================  =============
@@ -573,6 +585,8 @@ For load and store instructions (``LD``, ``LDX``, ``ST``, and ``STX``), the 
**sz (size)**

  The size modifier is one of:



  .. table:: Size modifier



    ====  =====  =====================

    size  value  description

    ====  =====  =====================
@@ -641,6 +655,8 @@ The 'imm' field is used to encode the actual atomic operation. 
Simple atomic operation use a subset of the values defined to encode

arithmetic operations in the 'imm' field to encode the atomic operation:



.. table:: Simple atomic operations



  ========  =====  ===========

  imm       value  description

  ========  =====  ===========
@@ -662,6 +678,8 @@ XOR 0xa0 atomic xor 
In addition to the simple atomic operations, there also is a modifier and

two complex atomic operations:



.. table:: Complex atomic operations



===========  ================  ===========================

imm          value             description

===========  ================  ===========================
@@ -695,6 +713,8 @@ The following table defines a set of ``{IMM, DW, LD}`` instructions 
with opcode subtypes in the 'src_reg' field, using new terms such as "map"

defined further below:



.. table:: 64-bit immediate instructions



  =======  =========================================  ===========  ==============

  src_reg  pseudocode                                 imm type     dst type

  =======  =========================================  ===========  ==============