Delete old x86 validator.

src/trusted/validator/x86/decoder/generator/README

-This directory implements the decoder table generator used by
-native_client/src/trusted/validator/x86/decoder. See the README in
-that directory for more information on how instructions are
-modeled. In particular, note the sections on "Modeled Instructions",
-"Opcode Sequences", and "Instruction Arguments".
-
-Modeled instructions specify what assembly instructions are recognized
-by the decoder. The form used is based on the AMD (R) document
-24594-Rev.3.14-September 2007, "AMD64 Architecture Programmer's manual
-Volume 3: General-Purpose and System Instructions", and Intel (R)
-docuements 253666-030US - March 2009, "Intel 654 and IA-32
-Architectures Software Developer's Manual, Volume2A: Instruction Set
-Reference, A-M" and 253667-030US - March 2009, "Intel 654 and IA-32
-Architectures Software Developer's Manual, Volume2B: Instruction Set
-Reference, N-Z".  In particular, it tries to follow the print forms
-defined by AMD's "Appendex section A.1 - Opcode-Syntax Notation", or
-Intel's "Appendix Section A.2 - Key To Abbreviations".
-
-Source files:
--------------
-
-modeled_nacl_inst.{c,h}
-
-   Defines structures to hold modeled instructions, and a
-   print routine to print these modeled instructions.
-
-ncdecode_tablegen.{h,c}
-
-   Implements the table generator executable. Includes:
-
-       code to add modeled instructions (one by one).
-
-       code to check consistency of the modeled instructions.
-
-       code to print out generated tables that encode the modeled
-       instructions.
-
-       code to print out a human readable form of the modeled
-       instructions, so that it easy to see what instructions are
-       being encoded into the generated tables.
-
-nacl_regsgen.{c,h}
-
-   Implements code that generates header files containing the
-   set of general purpose registers (and thier correlations) for
-   both x86-32 and x86-64.
-
-ncdecode_forms.{h,c}
-
-   Implements code that takes string definitions of modeled
-   instructions, and generates the corresponding appropriate calls to
-   model the instructions, as expected by code in
-   ncdecode_tablegen.h. The modeled instructions define an opcode
-   sequence, an instruction mnemonic, and instruction arguments
-   expected by that instruction.
-
-ncdecode_onebyte.c
-
-   Defines one byte opcodes for 386, return, and system instructions.
-
-ncdecodeX87.c
-
-   Defines the x87 floating point instructions.
-
-ncdecode_0F.c
-
-   Defines the multibyte opcode instructions, which begin with byte
-   0F.  Excludes sse instructions ((except for the Ldmxcse, Stmxcsr,
-   Lfence, and Mfence instructions).
-
-ncdecode_sse.c
-
-   Defines sse instructions (except for the Ldmxcse, Stmxcsr, Lfence,
-   and Mfence instructions, which are defined in ncdecode_0F.c).
-
-defsize64.{c,h}
-
-   Defines instructions (mnemonics) which for x86-64, always have
-   64-bit arguments, and ignores operand size specified by prefix
-   bytes.
-
-lock_insts.{c,h}
-
-   Defines instructions (mnemonics) that can use a lock prefix.
-
-long_mode.{c,h}
-
-   Defines instructions (mnemonics) that are considered LongMode in
-   x86-64.
-
-nacl_illegal.{c,h}
-
-   Defines instructions (mnemonics) that are (apriori) considered
-   illegal in native client.
-
-nc_def_jumps.{c,h}
-
-   Defines instructions (mnemonics) that do either conditional or
-   unconditional jumps.
-
-zero_extends.{c,h}
-
-   Defines instructions (mnemonics) that native client assumes to do
-   zero-extension when assigning a 32-bit value to a 64-bit register.
-
-   Note: This is not the same as specified in the instruction manuals.
-   Rather, it only includes those that have been whitelisted to do
-   this for native client.
-
-nc_rep_prefix.{c,h}
-
-   Defines instructions (mnemonics) that can use the REP/REPE/REPZ
-   (F3) and REPNE/REPNZ (F2) prefix.
-
-nacl_disallows.enum
-
-   Defines an enumerated type of possible reasons why a modeled
-   instruction may not be accepted by the table generator.
-
-ncdecode_st.{c,h}
-
-   Symbol table used to encode names used when defining modeled
-   instructions. This includes common registers (i.e. the stack and
-   ip), as well as functions that convert instruction arguments
-   (strings) into the corresponding modeled instruction data.
-
-nc_compress.{c,h}
-
-   Defines code that compresses the data used to model instructions,
-   so that the corresponding tables generated are smaller.
-
-ncval_simplify.{c,h}
-
-   Code that simplifies (fully) modeled instructions into patterns
-   that can be used by the x86-64 validator to parse the corresponding
-   instructions.
-
-force_cpp.cc
-
-   Dummy file to make scons understand that the corresponding
-   executable contains c++ code.
-
-build.scons
-
-   The scons file to construct the needed tables for the x86 decoders
-   and validators.
-
-   Note: The tables are not automatically rebuilt on each call to
-   scons. Rather, to regenerate the corresponding tables, one must do
-   the following (in the native_client directory):
-
-   .> ./scons --mode=opt-linux platform=x86-64 valclean
-   .> ./scons --mode=opt-linux platform=x86-64 valgen
-
-Generated Tables
-----------------
-
-The following tables are generated by scons (when call with argument
-"valgen"):
-
-gen/nacl_disallows.h
-
-   The generated enumerated type defined by file nacl_disallows.enum
-
-gen/nacl_disallows_impl.h
-
-   The generated implementation of the function NaClDisallowsFlagName.
-
-gen/nc_opcode_table_32.h
-
-   The generated tables for the full decoder for x86-32 instructions.
-
-gen/nc_opcode_table_64.h
-
-   The generated tables for the full decoder for x86-64 instructions.
-
-gen/nc_subregs_64.h
-
-   The generated mapping of all possible registers in x86-64, to the
-   index of the (64-bit) register that is is a subregister of.
-
-gen/nc_subregs_32.h
-
-   The generated mapping of all possible registers in x86-32, to the
-   index of the (32-bit) register that is is a subregister of.
-
-Modeled Instructions
---------------------
-
-To make it easier to see what instructions are generated, and test
-that changes to the code in this directory has NOT changed that set,
-the following test files exists:
-
-testdata/64/modeled_insts.txt
-
-   The instructions recognized by the full decoder for x86-64.
-
-testdata/32/modeled_insts.txt
-
-   The instructions recognized by the full decoder for x86-32.
-
-testdata/64/ncval_reg_sfi_modeled_insts.txt
-
-   The instruction patterns (generated by ncval_simplify.c) that
-   will be used by the x86-64 register SFI validator.
-
-testdata/32/ncval_reg_sfi_modeled_insts.txt
-
-   The instruction patterns (generated by ncval_simplify.c) that
-   will be used by the x86-32 register SFI validator.
-
-   Note: Deprecated and will be removed, since the x86-32 version
-   of the register SFI validator does not make sense.