greatly improve the LLVM IR bitcode encoding documentation,
patch by Peter Housel! llvm-svn: 85479
This commit is contained in:
Chris Lattner
parent
d74ffbde67
commit
e9006fe142
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@ -27,6 +27,15 @@
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<li><a href="#llvmir">LLVM IR Encoding</a>
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<ol>
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<li><a href="#basics">Basics</a></li>
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<li><a href="#MODULE_BLOCK">MODULE_BLOCK Contents</a></li>
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<li><a href="#PARAMATTR_BLOCK">PARAMATTR_BLOCK Contents</a></li>
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<li><a href="#TYPE_BLOCK">TYPE_BLOCK Contents</a></li>
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<li><a href="#CONSTANTS_BLOCK">CONSTANTS_BLOCK Contents</a></li>
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<li><a href="#FUNCTION_BLOCK">FUNCTION_BLOCK Contents</a></li>
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<li><a href="#TYPE_SYMTAB_BLOCK">TYPE_SYMTAB_BLOCK Contents</a></li>
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<li><a href="#VALUE_SYMTAB_BLOCK">VALUE_SYMTAB_BLOCK Contents</a></li>
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<li><a href="#METADATA_BLOCK">METADATA_BLOCK Contents</a></li>
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<li><a href="#METADATA_ATTACHMENT">METADATA_ATTACHMENT Contents</a></li>
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</ol>
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</li>
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</ol>
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@ -220,7 +229,7 @@ A bitstream is a sequential series of <a href="#blocks">Blocks</a> and
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abbreviation ID encoded as a fixed-bitwidth field. The width is specified by
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the current block, as described below. The value of the abbreviation ID
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specifies either a builtin ID (which have special meanings, defined below) or
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one of the abbreviation IDs defined by the stream itself.
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one of the abbreviation IDs defined for the current block by the stream itself.
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</p>
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<p>
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@ -258,7 +267,7 @@ application specific. Nested blocks capture the hierarchical structure of the da
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encoded in it, and various properties are associated with blocks as the file is
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parsed. Block definitions allow the reader to efficiently skip blocks
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in constant time if the reader wants a summary of blocks, or if it wants to
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efficiently skip data they do not understand. The LLVM IR reader uses this
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efficiently skip data it does not understand. The LLVM IR reader uses this
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mechanism to skip function bodies, lazily reading them on demand.
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</p>
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@ -268,7 +277,8 @@ block. In particular, each block maintains:
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</p>
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<ol>
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<li>A current abbrev id width. This value starts at 2, and is set every time a
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<li>A current abbrev id width. This value starts at 2 at the beginning of
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the stream, and is set every time a
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block record is entered. The block entry specifies the abbrev id width for
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the body of the block.</li>
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@ -335,13 +345,14 @@ an even multiple of 32-bits.
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<div class="doc_text">
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<p>
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Data records consist of a record code and a number of (up to) 64-bit integer
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values. The interpretation of the code and values is application specific and
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there are multiple different ways to encode a record (with an unabbrev record or
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with an abbreviation). In the LLVM IR format, for example, there is a record
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Data records consist of a record code and a number of (up to) 64-bit
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integer values. The interpretation of the code and values is
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application specific and may vary between different block types.
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Records can be encoded either using an unabbrev record, or with an
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abbreviation. In the LLVM IR format, for example, there is a record
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which encodes the target triple of a module. The code is
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<tt>MODULE_CODE_TRIPLE</tt>, and the values of the record are the ASCII codes
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for the characters in the string.
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<tt>MODULE_CODE_TRIPLE</tt>, and the values of the record are the
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ASCII codes for the characters in the string.
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</p>
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</div>
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@ -358,7 +369,7 @@ Encoding</a></div>
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<p>
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An <tt>UNABBREV_RECORD</tt> provides a default fallback encoding, which is both
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completely general and extremely inefficient. It can describe an arbitrary
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record by emitting the code and operands as vbrs.
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record by emitting the code and operands as VBRs.
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</p>
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<p>
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@ -391,6 +402,11 @@ allows the files to be completely self describing. The actual encoding of
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abbreviations is defined below.
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</p>
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<p>The record code, which is the first field of an abbreviated record,
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may be encoded in the abbreviation definition (as a literal
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operand) or supplied in the abbreviated record (as a Fixed or VBR
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operand value).</p>
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</div>
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<!-- ======================================================================= -->
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@ -409,8 +425,9 @@ emitted.
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<p>
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Abbreviations can be determined dynamically per client, per file. Because the
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abbreviations are stored in the bitstream itself, different streams of the same
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format can contain different sets of abbreviations if the specific stream does
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not need it. As a concrete example, LLVM IR files usually emit an abbreviation
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format can contain different sets of abbreviations according to the needs
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of the specific stream.
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As a concrete example, LLVM IR files usually emit an abbreviation
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for binary operators. If a specific LLVM module contained no or few binary
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operators, the abbreviation does not need to be emitted.
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</p>
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@ -431,7 +448,8 @@ defined abbreviations in the scope of this block. This definition only exists
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inside this immediate block — it is not visible in subblocks or enclosing
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blocks. Abbreviations are implicitly assigned IDs sequentially starting from 4
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(the first application-defined abbreviation ID). Any abbreviations defined in a
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<tt>BLOCKINFO</tt> record receive IDs first, in order, followed by any
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<tt>BLOCKINFO</tt> record for the particular block type
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receive IDs first, in order, followed by any
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abbreviations defined within the block itself. Abbreviated data records
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reference this ID to indicate what abbreviation they are invoking.
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</p>
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@ -461,31 +479,32 @@ emitted as their code, followed by the extra data.
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<p>The possible operand encodings are:</p>
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<ol>
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<li>Fixed: The field should be emitted as
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<ul>
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<li>Fixed (code 1): The field should be emitted as
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a <a href="#fixedwidth">fixed-width value</a>, whose width is specified by
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the operand's extra data.</li>
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<li>VBR: The field should be emitted as
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<li>VBR (code 2): The field should be emitted as
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a <a href="#variablewidth">variable-width value</a>, whose width is
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specified by the operand's extra data.</li>
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<li>Array: This field is an array of values. The array operand
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has no extra data, but expects another operand to follow it which indicates
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<li>Array (code 3): This field is an array of values. The array operand
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has no extra data, but expects another operand to follow it, indicating
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the element type of the array. When reading an array in an abbreviated
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record, the first integer is a vbr6 that indicates the array length,
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followed by the encoded elements of the array. An array may only occur as
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the last operand of an abbreviation (except for the one final operand that
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gives the array's type).</li>
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<li>Char6: This field should be emitted as
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<li>Char6 (code 4): This field should be emitted as
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a <a href="#char6">char6-encoded value</a>. This operand type takes no
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extra data.</li>
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<li>Blob: This field is emitted as a vbr6, followed by padding to a
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extra data. Char6 encoding is normally used as an array element type.
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</li>
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<li>Blob (code 5): This field is emitted as a vbr6, followed by padding to a
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32-bit boundary (for alignment) and an array of 8-bit objects. The array of
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bytes is further followed by tail padding to ensure that its total length is
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a multiple of 4 bytes. This makes it very efficient for the reader to
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decode the data without having to make a copy of it: it can use a pointer to
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the data in the mapped in file and poke directly at it. A blob may only
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occur as the last operand of an abbreviation.</li>
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</ol>
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</ul>
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<p>
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For example, target triples in LLVM modules are encoded as a record of the
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@ -517,7 +536,7 @@ as:
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<ol>
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<li>The first value, 4, is the abbreviation ID for this abbreviation.</li>
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<li>The second value, 2, is the code for <tt>TRIPLE</tt> in LLVM IR files.</li>
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<li>The second value, 2, is the record code for <tt>TRIPLE</tt> records within LLVM IR file <tt>MODULE_BLOCK</tt> blocks.</li>
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<li>The third value, 4, is the length of the array.</li>
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<li>The rest of the values are the char6 encoded values
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for <tt>"abcd"</tt>.</li>
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@ -541,7 +560,7 @@ used for any other string value.
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<p>
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In addition to the basic block structure and record encodings, the bitstream
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also defines specific builtin block types. These block types specify how the
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also defines specific built-in block types. These block types specify how the
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stream is to be decoded or other metadata. In the future, new standard blocks
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may be added. Block IDs 0-7 are reserved for standard blocks.
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</p>
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@ -569,7 +588,7 @@ blocks. The currently specified records are:
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</div>
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<p>
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The <tt>SETBID</tt> record indicates which block ID is being
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The <tt>SETBID</tt> record (code 1) indicates which block ID is being
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described. <tt>SETBID</tt> records can occur multiple times throughout the
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block to change which block ID is being described. There must be
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a <tt>SETBID</tt> record prior to any other records.
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@ -584,13 +603,13 @@ in <tt>BLOCKINFO</tt> blocks receive abbreviation IDs as described
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in <tt><a href="#DEFINE_ABBREV">DEFINE_ABBREV</a></tt>.
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</p>
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<p>The <tt>BLOCKNAME</tt> can optionally occur in this block. The elements of
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the record are the bytes for the string name of the block. llvm-bcanalyzer uses
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<p>The <tt>BLOCKNAME</tt> record (code 2) can optionally occur in this block. The elements of
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the record are the bytes of the string name of the block. llvm-bcanalyzer can use
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this to dump out bitcode files symbolically.</p>
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<p>The <tt>SETRECORDNAME</tt> record can optionally occur in this block. The
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first entry is a record ID number and the rest of the elements of the record are
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the bytes for the string name of the record. llvm-bcanalyzer uses
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<p>The <tt>SETRECORDNAME</tt> record (code 3) can also optionally occur in this block. The
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first operand value is a record ID number, and the rest of the elements of the record are
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the bytes for the string name of the record. llvm-bcanalyzer can use
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this to dump out bitcode files symbolically.</p>
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<p>
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@ -626,7 +645,7 @@ Each of the fields are 32-bit fields stored in little endian form (as with
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the rest of the bitcode file fields). The Magic number is always
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<tt>0x0B17C0DE</tt> and the version is currently always <tt>0</tt>. The Offset
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field is the offset in bytes to the start of the bitcode stream in the file, and
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the Size field is a size in bytes of the stream. CPUType is a target-specific
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the Size field is the size in bytes of the stream. CPUType is a target-specific
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value that can be used to encode the CPU of the target.
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</p>
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@ -681,26 +700,28 @@ When combined with the bitcode magic number and viewed as bytes, this is
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<div class="doc_text">
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<p>
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<a href="#variablewidth">Variable Width Integers</a> are an efficient way to
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encode arbitrary sized unsigned values, but is an extremely inefficient way to
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encode signed values (as signed values are otherwise treated as maximally large
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unsigned values).
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<a href="#variablewidth">Variable Width Integer</a> encoding is an efficient way to
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encode arbitrary sized unsigned values, but is an extremely inefficient for
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encoding signed values, as signed values are otherwise treated as maximally large
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unsigned values.
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</p>
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<p>
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As such, signed vbr values of a specific width are emitted as follows:
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As such, signed VBR values of a specific width are emitted as follows:
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</p>
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<ul>
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<li>Positive values are emitted as vbrs of the specified width, but with their
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<li>Positive values are emitted as VBRs of the specified width, but with their
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value shifted left by one.</li>
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<li>Negative values are emitted as vbrs of the specified width, but the negated
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<li>Negative values are emitted as VBRs of the specified width, but the negated
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value is shifted left by one, and the low bit is set.</li>
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</ul>
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<p>
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With this encoding, small positive and small negative values can both be emitted
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efficiently.
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With this encoding, small positive and small negative values can both
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be emitted efficiently. Signed VBR encoding is used in
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<tt>CST_CODE_INTEGER</tt> and <tt>CST_CODE_WIDE_INTEGER</tt> records
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within <tt>CONSTANTS_BLOCK</tt> blocks.
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</p>
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</div>
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@ -716,21 +737,23 @@ LLVM IR is defined with the following blocks:
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</p>
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<ul>
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<li>8 — <tt>MODULE_BLOCK</tt> — This is the top-level block that
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<li>8 — <a href="#MODULE_BLOCK"><tt>MODULE_BLOCK</tt></a> — This is the top-level block that
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contains the entire module, and describes a variety of per-module
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information.</li>
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<li>9 — <tt>PARAMATTR_BLOCK</tt> — This enumerates the parameter
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<li>9 — <a href="#PARAMATTR_BLOCK"><tt>PARAMATTR_BLOCK</tt></a> — This enumerates the parameter
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attributes.</li>
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<li>10 — <tt>TYPE_BLOCK</tt> — This describes all of the types in
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<li>10 — <a href="#TYPE_BLOCK"><tt>TYPE_BLOCK</tt></a> — This describes all of the types in
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the module.</li>
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<li>11 — <tt>CONSTANTS_BLOCK</tt> — This describes constants for a
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<li>11 — <a href="#CONSTANTS_BLOCK"><tt>CONSTANTS_BLOCK</tt></a> — This describes constants for a
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module or function.</li>
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<li>12 — <tt>FUNCTION_BLOCK</tt> — This describes a function
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<li>12 — <a href="#FUNCTION_BLOCK"><tt>FUNCTION_BLOCK</tt></a> — This describes a function
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body.</li>
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<li>13 — <tt>TYPE_SYMTAB_BLOCK</tt> — This describes the type symbol
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<li>13 — <a href="#TYPE_SYMTAB_BLOCK"><tt>TYPE_SYMTAB_BLOCK</tt></a> — This describes the type symbol
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table.</li>
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<li>14 — <tt>VALUE_SYMTAB_BLOCK</tt> — This describes a value symbol
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<li>14 — <a href="#VALUE_SYMTAB_BLOCK"><tt>VALUE_SYMTAB_BLOCK</tt></a> — This describes a value symbol
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table.</li>
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<li>15 — <a href="#METADATA_BLOCK"><tt>METADATA_BLOCK</tt></a> — This describes metadata items.</li>
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<li>16 — <a href="#METADATA_ATTACHMENT"><tt>METADATA_ATTACHMENT</tt></a> — This contains records associating metadata with function instruction values.</li>
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</ul>
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</div>
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@ -741,7 +764,387 @@ LLVM IR is defined with the following blocks:
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<div class="doc_text">
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<p>
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<p>The <tt>MODULE_BLOCK</tt> block (id 8) is the top-level block for LLVM
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bitcode files, and each bitcode file must contain exactly one. In
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addition to records (described below) containing information
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about the module, a <tt>MODULE_BLOCK</tt> block may contain the
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following sub-blocks:
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</p>
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<ul>
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<li><a href="#BLOCKINFO"><tt>BLOCKINFO</tt></a></li>
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<li><a href="#PARAMATTR_BLOCK"><tt>PARAMATTR_BLOCK</tt></a></li>
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<li><a href="#TYPE_BLOCK"><tt>TYPE_BLOCK</tt></a></li>
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<li><a href="#TYPE_SYMTAB_BLOCK"><tt>TYPE_SYMTAB_BLOCK</tt></a></li>
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<li><a href="#VALUE_SYMTAB_BLOCK"><tt>VALUE_SYMTAB_BLOCK</tt></a></li>
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<li><a href="#CONSTANTS_BLOCK"><tt>CONSTANTS_BLOCK</tt></a></li>
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<li><a href="#FUNCTION_BLOCK"><tt>FUNCTION_BLOCK</tt></a></li>
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<li><a href="#METADATA_BLOCK"><tt>METADATA_BLOCK</tt></a></li>
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</ul>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsubsection"><a name="MODULE_CODE_VERSION">MODULE_CODE_VERSION Record</a>
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</div>
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<div class="doc_text">
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<p><tt>[VERSION, version#]</tt></p>
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<p>The <tt>VERSION</tt> record (code 1) contains a single value
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indicating the format version. Only version 0 is supported at this
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time.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsubsection"><a name="MODULE_CODE_TRIPLE">MODULE_CODE_TRIPLE Record</a>
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</div>
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<div class="doc_text">
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<p><tt>[TRIPLE, ...string...]</tt></p>
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<p>The <tt>TRIPLE</tt> record (code 2) contains a variable number of
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values representing the bytes of the <tt>target triple</tt>
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specification string.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsubsection"><a name="MODULE_CODE_DATALAYOUT">MODULE_CODE_DATALAYOUT Record</a>
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</div>
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<div class="doc_text">
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<p><tt>[DATALAYOUT, ...string...]</tt></p>
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<p>The <tt>DATALAYOUT</tt> record (code 3) contains a variable number of
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values representing the bytes of the <tt>target datalayout</tt>
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specification string.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsubsection"><a name="MODULE_CODE_ASM">MODULE_CODE_ASM Record</a>
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</div>
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<div class="doc_text">
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<p><tt>[ASM, ...string...]</tt></p>
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<p>The <tt>ASM</tt> record (code 4) contains a variable number of
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values representing the bytes of <tt>module asm</tt> strings, with
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individual assembly blocks separated by newline (ASCII 10) characters.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsubsection"><a name="MODULE_CODE_SECTIONNAME">MODULE_CODE_SECTIONNAME Record</a>
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</div>
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<div class="doc_text">
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<p><tt>[SECTIONNAME, ...string...]</tt></p>
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<p>The <tt>SECTIONNAME</tt> record (code 5) contains a variable number
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of values representing the bytes of a single section name
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string. There should be one <tt>SECTIONNAME</tt> record for each
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section name referenced (e.g., in global variable or function
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<tt>section</tt> attributes) within the module. These records can be
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referenced by the 1-based index in the <i>section</i> fields of
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<tt>GLOBALVAR</tt> or <tt>FUNCTION</tt> records.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsubsection"><a name="MODULE_CODE_DEPLIB">MODULE_CODE_DEPLIB Record</a>
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</div>
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<div class="doc_text">
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<p><tt>[DEPLIB, ...string...]</tt></p>
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<p>The <tt>DEPLIB</tt> record (code 6) contains a variable number of
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values representing the bytes of a single dependent library name
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string, one of the libraries mentioned in a <tt>deplibs</tt>
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declaration. There should be one <tt>DEPLIB</tt> record for each
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library name referenced.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsubsection"><a name="MODULE_CODE_GLOBALVAR">MODULE_CODE_GLOBALVAR Record</a>
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</div>
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|
||||
<div class="doc_text">
|
||||
<p><tt>[GLOBALVAR, pointer type, isconst, initid, linkage, alignment, section, visibility, threadlocal]</tt></p>
|
||||
|
||||
<p>The <tt>GLOBALVAR</tt> record (code 7) marks the declaration or
|
||||
definition of a global variable. The operand fields are:</p>
|
||||
|
||||
<ul>
|
||||
<li><i>pointer type</i>: The type index of the pointer type used to point to
|
||||
this global variable</li>
|
||||
|
||||
<li><i>isconst</i>: Non-zero if the variable is treated as constant within
|
||||
the module, or zero if it is not</li>
|
||||
|
||||
<li><i>initid</i>: If non-zero, the value index of the initializer for this
|
||||
variable, plus 1.</li>
|
||||
|
||||
<li><a name="linkage"><i>linkage</i></a>: An encoding of the linkage
|
||||
type for this variable:
|
||||
<ul>
|
||||
<li><tt>external</tt>: code 0</li>
|
||||
<li><tt>weak</tt>: code 1</li>
|
||||
<li><tt>appending</tt>: code 2</li>
|
||||
<li><tt>internal</tt>: code 3</li>
|
||||
<li><tt>linkonce</tt>: code 4</li>
|
||||
<li><tt>dllimport</tt>: code 5</li>
|
||||
<li><tt>dllexport</tt>: code 6</li>
|
||||
<li><tt>extern_weak</tt>: code 7</li>
|
||||
<li><tt>common</tt>: code 8</li>
|
||||
<li><tt>private</tt>: code 9</li>
|
||||
<li><tt>weak_odr</tt>: code 10</li>
|
||||
<li><tt>linkonce_odr</tt>: code 11</li>
|
||||
<li><tt>available_externally</tt>: code 12</li>
|
||||
<li><tt>linker_private</tt>: code 13</li>
|
||||
</ul>
|
||||
</li>
|
||||
|
||||
<li><i>alignment</i>: The logarithm base 2 of the variable's requested
|
||||
alignment, plus 1</li>
|
||||
|
||||
<li><i>section</i>: If non-zero, the 1-based section index in the
|
||||
table of <a href="#MODULE_CODE_SECTIONNAME">MODULE_CODE_SECTIONNAME</a>
|
||||
entries.</li>
|
||||
|
||||
<li><a name="visibility"><i>visibility</i></a>: If present, an
|
||||
encoding of the visibility of this variable:
|
||||
<ul>
|
||||
<li><tt>default</tt>: code 0</li>
|
||||
<li><tt>hidden</tt>: code 1</li>
|
||||
<li><tt>protected</tt>: code 2</li>
|
||||
</ul>
|
||||
</li>
|
||||
|
||||
<li><i>threadlocal</i>: If present and non-zero, indicates that the variable
|
||||
is <tt>thread_local</tt></li>
|
||||
|
||||
</ul>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsubsection"><a name="MODULE_CODE_FUNCTION">MODULE_CODE_FUNCTION Record</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p><tt>[FUNCTION, type, callingconv, isproto, linkage, paramattr, alignment, section, visibility, gc]</tt></p>
|
||||
|
||||
<p>The <tt>FUNCTION</tt> record (code 8) marks the declaration or
|
||||
definition of a function. The operand fields are:</p>
|
||||
|
||||
<ul>
|
||||
<li><i>type</i>: The type index of the function type describing this function</li>
|
||||
|
||||
<li><i>callingconv</i>: The calling convention number:
|
||||
<ul>
|
||||
<li><tt>ccc</tt>: code 0</li>
|
||||
<li><tt>fastcc</tt>: code 8</li>
|
||||
<li><tt>coldcc</tt>: code 9</li>
|
||||
<li><tt>x86_stdcallcc</tt>: code 64</li>
|
||||
<li><tt>x86_fastcallcc</tt>: code 65</li>
|
||||
<li><tt>arm_apcscc</tt>: code 66</li>
|
||||
<li><tt>arm_aapcscc</tt>: code 67</li>
|
||||
<li><tt>arm_aapcs_vfpcc</tt>: code 68</li>
|
||||
</ul>
|
||||
</li>
|
||||
|
||||
<li><i>isproto</i>: Non-zero if this entry represents a declaration
|
||||
rather than a definition</li>
|
||||
|
||||
<li><i>linkage</i>: An encoding of the <a href="#linkage">linkage type</a>
|
||||
for this function</li>
|
||||
|
||||
<li><i>paramattr</i>: If nonzero, the 1-based parameter attribute index
|
||||
into the table of <a href="#PARAMATTR_CODE_ENTRY">PARAMATTR_CODE_ENTRY</a>
|
||||
entries.</li>
|
||||
|
||||
<li><i>alignment</i>: The logarithm base 2 of the function's requested
|
||||
alignment, plus 1</li>
|
||||
|
||||
<li><i>section</i>: If non-zero, the 1-based section index in the
|
||||
table of <a href="#MODULE_CODE_SECTIONNAME">MODULE_CODE_SECTIONNAME</a>
|
||||
entries.</li>
|
||||
|
||||
<li><i>visibility</i>: An encoding of the <a href="#visibility">visibility</a>
|
||||
of this function</li>
|
||||
|
||||
<li><i>gc</i>: If present and nonzero, the 1-based garbage collector
|
||||
index in the table of
|
||||
<a href="#MODULE_CODE_GCNAME">MODULE_CODE_GCNAME</a> entries.</li>
|
||||
</ul>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsubsection"><a name="MODULE_CODE_ALIAS">MODULE_CODE_ALIAS Record</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p><tt>[ALIAS, alias type, aliasee val#, linkage, visibility]</tt></p>
|
||||
|
||||
<p>The <tt>ALIAS</tt> record (code 9) marks the definition of an
|
||||
alias. The operand fields are</p>
|
||||
|
||||
<ul>
|
||||
<li><i>alias type</i>: The type index of the alias</li>
|
||||
|
||||
<li><i>aliasee val#</i>: The value index of the aliased value</li>
|
||||
|
||||
<li><i>linkage</i>: An encoding of the <a href="#linkage">linkage type</a>
|
||||
for this alias</li>
|
||||
|
||||
<li><i>visibility</i>: If present, an encoding of the
|
||||
<a href="#visibility">visibility</a> of the alias</li>
|
||||
|
||||
</ul>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsubsection"><a name="MODULE_CODE_PURGEVALS">MODULE_CODE_PURGEVALS Record</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
<p><tt>[PURGEVALS, numvals]</tt></p>
|
||||
|
||||
<p>The <tt>PURGEVALS</tt> record (code 10) resets the module-level
|
||||
value list to the size given by the single operand value. Module-level
|
||||
value list items are added by <tt>GLOBALVAR</tt>, <tt>FUNCTION</tt>,
|
||||
and <tt>ALIAS</tt> records. After a <tt>PURGEVALS</tt> record is seen,
|
||||
new value indices will start from the given <i>numvals</i> value.</p>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsubsection"><a name="MODULE_CODE_GCNAME">MODULE_CODE_GCNAME Record</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
<p><tt>[GCNAME, ...string...]</tt></p>
|
||||
|
||||
<p>The <tt>GCNAME</tt> record (code 11) contains a variable number of
|
||||
values representing the bytes of a single garbage collector name
|
||||
string. There should be one <tt>GCNAME</tt> record for each garbage
|
||||
collector name referenced in function <tt>gc</tt> attributes within
|
||||
the module. These records can be referenced by 1-based index in the <i>gc</i>
|
||||
fields of <tt>FUNCTION</tt> records.</p>
|
||||
</div>
|
||||
|
||||
<!-- ======================================================================= -->
|
||||
<div class="doc_subsection"><a name="PARAMATTR_BLOCK">PARAMATTR_BLOCK Contents</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p>The <tt>PARAMATTR_BLOCK</tt> block (id 9) ...
|
||||
</p>
|
||||
|
||||
</div>
|
||||
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsubsection"><a name="PARAMATTR_CODE_ENTRY">PARAMATTR_CODE_ENTRY Record</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p><tt>[ENTRY, paramidx0, attr0, paramidx1, attr1...]</tt></p>
|
||||
|
||||
<p>The <tt>ENTRY</tt> record (code 1) ...
|
||||
</p>
|
||||
</div>
|
||||
|
||||
<!-- ======================================================================= -->
|
||||
<div class="doc_subsection"><a name="TYPE_BLOCK">TYPE_BLOCK Contents</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p>The <tt>TYPE_BLOCK</tt> block (id 10) ...
|
||||
</p>
|
||||
|
||||
</div>
|
||||
|
||||
|
||||
<!-- ======================================================================= -->
|
||||
<div class="doc_subsection"><a name="CONSTANTS_BLOCK">CONSTANTS_BLOCK Contents</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p>The <tt>CONSTANTS_BLOCK</tt> block (id 11) ...
|
||||
</p>
|
||||
|
||||
</div>
|
||||
|
||||
|
||||
<!-- ======================================================================= -->
|
||||
<div class="doc_subsection"><a name="FUNCTION_BLOCK">FUNCTION_BLOCK Contents</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p>The <tt>FUNCTION_BLOCK</tt> block (id 12) ...
|
||||
</p>
|
||||
|
||||
<p>In addition to the record types described below, a
|
||||
<tt>FUNCTION_BLOCK</tt> block may contain the following sub-blocks:
|
||||
</p>
|
||||
|
||||
<ul>
|
||||
<li><a href="#CONSTANTS_BLOCK"><tt>CONSTANTS_BLOCK</tt></a></li>
|
||||
<li><a href="#VALUE_SYMTAB_BLOCK"><tt>VALUE_SYMTAB_BLOCK</tt></a></li>
|
||||
<li><a href="#METADATA_ATTACHMENT"><tt>METADATA_ATTACHMENT</tt></a></li>
|
||||
</ul>
|
||||
|
||||
</div>
|
||||
|
||||
|
||||
<!-- ======================================================================= -->
|
||||
<div class="doc_subsection"><a name="TYPE_SYMTAB_BLOCK">TYPE_SYMTAB_BLOCK Contents</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p>The <tt>TYPE_SYMTAB_BLOCK</tt> block (id 13) ...
|
||||
</p>
|
||||
|
||||
</div>
|
||||
|
||||
|
||||
<!-- ======================================================================= -->
|
||||
<div class="doc_subsection"><a name="VALUE_SYMTAB_BLOCK">VALUE_SYMTAB_BLOCK Contents</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p>The <tt>VALUE_SYMTAB_BLOCK</tt> block (id 14) ...
|
||||
</p>
|
||||
|
||||
</div>
|
||||
|
||||
|
||||
<!-- ======================================================================= -->
|
||||
<div class="doc_subsection"><a name="METADATA_BLOCK">METADATA_BLOCK Contents</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p>The <tt>METADATA_BLOCK</tt> block (id 15) ...
|
||||
</p>
|
||||
|
||||
</div>
|
||||
|
||||
|
||||
<!-- ======================================================================= -->
|
||||
<div class="doc_subsection"><a name="METADATA_ATTACHMENT">METADATA_ATTACHMENT Contents</a>
|
||||
</div>
|
||||
|
||||
<div class="doc_text">
|
||||
|
||||
<p>The <tt>METADATA_ATTACHMENT</tt> block (id 16) ...
|
||||
</p>
|
||||
|
||||
</div>
|
||||
|
|
|
|||
Loading…
Reference in New Issue