X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=docs%2FBitCodeFormat.rst;h=d6e3099bdb63d8d620050f9c90916ad97a2511dd;hp=9363a62d0806b2730395bdf3e2f5bf73031c97ca;hb=ec63ff81dd85fcb1731ccfb07980a259cc974ee8;hpb=38f68c5a2e3993a3ae51421d82e57ccca8f6ec38 diff --git a/docs/BitCodeFormat.rst b/docs/BitCodeFormat.rst index 9363a62d080..d6e3099bdb6 100644 --- a/docs/BitCodeFormat.rst +++ b/docs/BitCodeFormat.rst @@ -28,8 +28,9 @@ Unlike XML, the bitstream format is a binary encoding, and unlike XML it provides a mechanism for the file to self-describe "abbreviations", which are effectively size optimizations for the content. -LLVM IR files may be optionally embedded into a `wrapper`_ structure that makes -it easy to embed extra data along with LLVM IR files. +LLVM IR files may be optionally embedded into a `wrapper`_ structure, or in a +`native object file`_. Both of these mechanisms make it easy to embed extra +data along with LLVM IR files. This document first describes the LLVM bitstream format, describes the wrapper format, then describes the record structure used by LLVM IR files. @@ -460,6 +461,19 @@ to the start of the bitcode stream in the file, and the Size field is the size in bytes of the stream. CPUType is a target-specific value that can be used to encode the CPU of the target. +.. _native object file: + +Native Object File Wrapper Format +================================= + +Bitcode files for LLVM IR may also be wrapped in a native object file +(i.e. ELF, COFF, Mach-O). The bitcode must be stored in a section of the +object file named ``.llvmbc``. This wrapper format is useful for accommodating +LTO in compilation pipelines where intermediate objects must be native object +files which contain metadata in other sections. + +Not all tools support this format. + .. _encoding of LLVM IR: LLVM IR Encoding @@ -658,7 +672,7 @@ for each library name referenced. MODULE_CODE_GLOBALVAR Record ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -``[GLOBALVAR, pointer type, isconst, initid, linkage, alignment, section, visibility, threadlocal, unnamed_addr, dllstorageclass]`` +``[GLOBALVAR, pointer type, isconst, initid, linkage, alignment, section, visibility, threadlocal, unnamed_addr, externally_initialized, dllstorageclass, comdat]`` The ``GLOBALVAR`` record (code 7) marks the declaration or definition of a global variable. The operand fields are: @@ -688,7 +702,8 @@ global variable. The operand fields are: * ``weak_odr``: code 10 * ``linkonce_odr``: code 11 * ``available_externally``: code 12 - * ``linker_private``: code 13 + * deprecated : code 13 + * deprecated : code 14 * alignment*: The logarithm base 2 of the variable's requested alignment, plus 1 @@ -713,7 +728,7 @@ global variable. The operand fields are: * *unnamed_addr*: If present and non-zero, indicates that the variable has ``unnamed_addr`` -.. _dllstorageclass: +.. _bcdllstorageclass: * *dllstorageclass*: If present, an encoding of the DLL storage class of this variable: @@ -726,7 +741,7 @@ global variable. The operand fields are: MODULE_CODE_FUNCTION Record ^^^^^^^^^^^^^^^^^^^^^^^^^^^ -``[FUNCTION, type, callingconv, isproto, linkage, paramattr, alignment, section, visibility, gc, prefix, dllstorageclass]`` +``[FUNCTION, type, callingconv, isproto, linkage, paramattr, alignment, section, visibility, gc, prologuedata, dllstorageclass, comdat, prefixdata, personalityfn]`` The ``FUNCTION`` record (code 8) marks the declaration or definition of a function. The operand fields are: @@ -739,6 +754,9 @@ function. The operand fields are: * ``coldcc``: code 9 * ``webkit_jscc``: code 12 * ``anyregcc``: code 13 + * ``preserve_mostcc``: code 14 + * ``preserve_allcc``: code 15 + * ``cxx_fast_tlscc``: code 17 * ``x86_stdcallcc``: code 64 * ``x86_fastcallcc``: code 65 * ``arm_apcscc``: code 66 @@ -767,10 +785,19 @@ function. The operand fields are: * *unnamed_addr*: If present and non-zero, indicates that the function has ``unnamed_addr`` -* *prefix*: If non-zero, the value index of the prefix data for this function, +* *prologuedata*: If non-zero, the value index of the prologue data for this function, plus 1. -* *dllstorageclass*: An encoding of the `dllstorageclass`_ of this function +* *dllstorageclass*: An encoding of the + :ref:`dllstorageclass` of this function + +* *comdat*: An encoding of the COMDAT of this function + +* *prefixdata*: If non-zero, the value index of the prefix data for this function, + plus 1. + +* *personalityfn*: If non-zero, the value index of the personality function for this function, + plus 1. MODULE_CODE_ALIAS Record ^^^^^^^^^^^^^^^^^^^^^^^^ @@ -788,7 +815,8 @@ fields are * *visibility*: If present, an encoding of the `visibility`_ of the alias -* *dllstorageclass*: If present, an encoding of the `dllstorageclass`_ of the alias +* *dllstorageclass*: If present, an encoding of the + :ref:`dllstorageclass` of the alias MODULE_CODE_PURGEVALS Record ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -824,7 +852,7 @@ in the *paramattr* field of module block `FUNCTION`_ records, or within the *attr* field of function block ``INST_INVOKE`` and ``INST_CALL`` records. Entries within ``PARAMATTR_BLOCK`` are constructed to ensure that each is unique -(i.e., no two indicies represent equivalent attribute lists). +(i.e., no two indices represent equivalent attribute lists). .. _PARAMATTR_CODE_ENTRY: @@ -877,7 +905,7 @@ table entry, which may be referenced by 0-based index from instructions, constants, metadata, type symbol table entries, or other type operator records. Entries within ``TYPE_BLOCK`` are constructed to ensure that each entry is -unique (i.e., no two indicies represent structurally equivalent types). +unique (i.e., no two indices represent structurally equivalent types). .. _TYPE_CODE_NUMENTRY: .. _NUMENTRY: @@ -1090,7 +1118,7 @@ named type. VALUE_SYMTAB_BLOCK Contents --------------------------- -The ``VALUE_SYMTAB_BLOCK`` block (id 14) ... +The ``VALUE_SYMTAB_BLOCK`` block (id 14) ... .. _METADATA_BLOCK: