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<a name="Output-of-Data"></a>
<h4 class="subsection">17.20.2 Output of Data</h4>


<dl>
<dt><a name="index-TARGET_005fASM_005fBYTE_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_BYTE_OP</strong></dt>
<dt><a name="index-TARGET_005fASM_005fALIGNED_005fHI_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_ALIGNED_HI_OP</strong></dt>
<dt><a name="index-TARGET_005fASM_005fALIGNED_005fSI_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_ALIGNED_SI_OP</strong></dt>
<dt><a name="index-TARGET_005fASM_005fALIGNED_005fDI_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_ALIGNED_DI_OP</strong></dt>
<dt><a name="index-TARGET_005fASM_005fALIGNED_005fTI_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_ALIGNED_TI_OP</strong></dt>
<dt><a name="index-TARGET_005fASM_005fUNALIGNED_005fHI_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_UNALIGNED_HI_OP</strong></dt>
<dt><a name="index-TARGET_005fASM_005fUNALIGNED_005fSI_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_UNALIGNED_SI_OP</strong></dt>
<dt><a name="index-TARGET_005fASM_005fUNALIGNED_005fDI_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_UNALIGNED_DI_OP</strong></dt>
<dt><a name="index-TARGET_005fASM_005fUNALIGNED_005fTI_005fOP"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_UNALIGNED_TI_OP</strong></dt>
<dd><p>These hooks specify assembly directives for creating certain kinds
of integer object.  The <code>TARGET_ASM_BYTE_OP</code> directive creates a
byte-sized object, the <code>TARGET_ASM_ALIGNED_HI_OP</code> one creates an
aligned two-byte object, and so on.  Any of the hooks may be
<code>NULL</code>, indicating that no suitable directive is available.
</p>
<p>The compiler will print these strings at the start of a new line,
followed immediately by the object&rsquo;s initial value.  In most cases,
the string should contain a tab, a pseudo-op, and then another tab.
</p></dd></dl>

<dl>
<dt><a name="index-TARGET_005fASM_005fINTEGER"></a>Target Hook: <em>bool</em> <strong>TARGET_ASM_INTEGER</strong> <em>(rtx <var>x</var>, unsigned int <var>size</var>, int <var>aligned_p</var>)</em></dt>
<dd><p>The <code>assemble_integer</code> function uses this hook to output an
integer object.  <var>x</var> is the object&rsquo;s value, <var>size</var> is its size
in bytes and <var>aligned_p</var> indicates whether it is aligned.  The
function should return <code>true</code> if it was able to output the
object.  If it returns false, <code>assemble_integer</code> will try to
split the object into smaller parts.
</p>
<p>The default implementation of this hook will use the
<code>TARGET_ASM_BYTE_OP</code> family of strings, returning <code>false</code>
when the relevant string is <code>NULL</code>.
</p></dd></dl>

<dl>
<dt><a name="index-TARGET_005fASM_005fDECL_005fEND"></a>Target Hook: <em>void</em> <strong>TARGET_ASM_DECL_END</strong> <em>(void)</em></dt>
<dd><p>Define this hook if the target assembler requires a special marker to
terminate an initialized variable declaration.
</p></dd></dl>

<dl>
<dt><a name="index-TARGET_005fASM_005fOUTPUT_005fADDR_005fCONST_005fEXTRA"></a>Target Hook: <em>bool</em> <strong>TARGET_ASM_OUTPUT_ADDR_CONST_EXTRA</strong> <em>(FILE *<var>file</var>, rtx <var>x</var>)</em></dt>
<dd><p>A target hook to recognize <var>rtx</var> patterns that <code>output_addr_const</code>
can&rsquo;t deal with, and output assembly code to <var>file</var> corresponding to
the pattern <var>x</var>.  This may be used to allow machine-dependent
<code>UNSPEC</code>s to appear within constants.
</p>
<p>If target hook fails to recognize a pattern, it must return <code>false</code>,
so that a standard error message is printed.  If it prints an error message
itself, by calling, for example, <code>output_operand_lossage</code>, it may just
return <code>true</code>.
</p></dd></dl>

<dl>
<dt><a name="index-ASM_005fOUTPUT_005fASCII"></a>Macro: <strong>ASM_OUTPUT_ASCII</strong> <em>(<var>stream</var>, <var>ptr</var>, <var>len</var>)</em></dt>
<dd><p>A C statement to output to the stdio stream <var>stream</var> an assembler
instruction to assemble a string constant containing the <var>len</var>
bytes at <var>ptr</var>.  <var>ptr</var> will be a C expression of type
<code>char *</code> and <var>len</var> a C expression of type <code>int</code>.
</p>
<p>If the assembler has a <code>.ascii</code> pseudo-op as found in the
Berkeley Unix assembler, do not define the macro
<code>ASM_OUTPUT_ASCII</code>.
</p></dd></dl>

<dl>
<dt><a name="index-ASM_005fOUTPUT_005fFDESC"></a>Macro: <strong>ASM_OUTPUT_FDESC</strong> <em>(<var>stream</var>, <var>decl</var>, <var>n</var>)</em></dt>
<dd><p>A C statement to output word <var>n</var> of a function descriptor for
<var>decl</var>.  This must be defined if <code>TARGET_VTABLE_USES_DESCRIPTORS</code>
is defined, and is otherwise unused.
</p></dd></dl>

<dl>
<dt><a name="index-CONSTANT_005fPOOL_005fBEFORE_005fFUNCTION"></a>Macro: <strong>CONSTANT_POOL_BEFORE_FUNCTION</strong></dt>
<dd><p>You may define this macro as a C expression.  You should define the
expression to have a nonzero value if GCC should output the constant
pool for a function before the code for the function, or a zero value if
GCC should output the constant pool after the function.  If you do
not define this macro, the usual case, GCC will output the constant
pool before the function.
</p></dd></dl>

<dl>
<dt><a name="index-ASM_005fOUTPUT_005fPOOL_005fPROLOGUE"></a>Macro: <strong>ASM_OUTPUT_POOL_PROLOGUE</strong> <em>(<var>file</var>, <var>funname</var>, <var>fundecl</var>, <var>size</var>)</em></dt>
<dd><p>A C statement to output assembler commands to define the start of the
constant pool for a function.  <var>funname</var> is a string giving
the name of the function.  Should the return type of the function
be required, it can be obtained via <var>fundecl</var>.  <var>size</var>
is the size, in bytes, of the constant pool that will be written
immediately after this call.
</p>
<p>If no constant-pool prefix is required, the usual case, this macro need
not be defined.
</p></dd></dl>

<dl>
<dt><a name="index-ASM_005fOUTPUT_005fSPECIAL_005fPOOL_005fENTRY"></a>Macro: <strong>ASM_OUTPUT_SPECIAL_POOL_ENTRY</strong> <em>(<var>file</var>, <var>x</var>, <var>mode</var>, <var>align</var>, <var>labelno</var>, <var>jumpto</var>)</em></dt>
<dd><p>A C statement (with or without semicolon) to output a constant in the
constant pool, if it needs special treatment.  (This macro need not do
anything for RTL expressions that can be output normally.)
</p>
<p>The argument <var>file</var> is the standard I/O stream to output the
assembler code on.  <var>x</var> is the RTL expression for the constant to
output, and <var>mode</var> is the machine mode (in case <var>x</var> is a
&lsquo;<samp>const_int</samp>&rsquo;).  <var>align</var> is the required alignment for the value
<var>x</var>; you should output an assembler directive to force this much
alignment.
</p>
<p>The argument <var>labelno</var> is a number to use in an internal label for
the address of this pool entry.  The definition of this macro is
responsible for outputting the label definition at the proper place.
Here is how to do this:
</p>
<div class="smallexample">
<pre class="smallexample"><code>(*targetm.asm_out.internal_label)</code> (<var>file</var>, &quot;LC&quot;, <var>labelno</var>);
</pre></div>

<p>When you output a pool entry specially, you should end with a
<code>goto</code> to the label <var>jumpto</var>.  This will prevent the same pool
entry from being output a second time in the usual manner.
</p>
<p>You need not define this macro if it would do nothing.
</p></dd></dl>

<dl>
<dt><a name="index-ASM_005fOUTPUT_005fPOOL_005fEPILOGUE"></a>Macro: <strong>ASM_OUTPUT_POOL_EPILOGUE</strong> <em>(<var>file</var> <var>funname</var> <var>fundecl</var> <var>size</var>)</em></dt>
<dd><p>A C statement to output assembler commands to at the end of the constant
pool for a function.  <var>funname</var> is a string giving the name of the
function.  Should the return type of the function be required, you can
obtain it via <var>fundecl</var>.  <var>size</var> is the size, in bytes, of the
constant pool that GCC wrote immediately before this call.
</p>
<p>If no constant-pool epilogue is required, the usual case, you need not
define this macro.
</p></dd></dl>

<dl>
<dt><a name="index-IS_005fASM_005fLOGICAL_005fLINE_005fSEPARATOR"></a>Macro: <strong>IS_ASM_LOGICAL_LINE_SEPARATOR</strong> <em>(<var>C</var>, <var>STR</var>)</em></dt>
<dd><p>Define this macro as a C expression which is nonzero if <var>C</var> is
used as a logical line separator by the assembler.  <var>STR</var> points
to the position in the string where <var>C</var> was found; this can be used if
a line separator uses multiple characters.
</p>
<p>If you do not define this macro, the default is that only
the character &lsquo;<samp>;</samp>&rsquo; is treated as a logical line separator.
</p></dd></dl>

<dl>
<dt><a name="index-TARGET_005fASM_005fOPEN_005fPAREN"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_OPEN_PAREN</strong></dt>
<dt><a name="index-TARGET_005fASM_005fCLOSE_005fPAREN"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_CLOSE_PAREN</strong></dt>
<dd><p>These target hooks are C string constants, describing the syntax in the
assembler for grouping arithmetic expressions.  If not overridden, they
default to normal parentheses, which is correct for most assemblers.
</p></dd></dl>

<p>These macros are provided by <samp>real.h</samp> for writing the definitions
of <code>ASM_OUTPUT_DOUBLE</code> and the like:
</p>
<dl>
<dt><a name="index-REAL_005fVALUE_005fTO_005fTARGET_005fSINGLE"></a>Macro: <strong>REAL_VALUE_TO_TARGET_SINGLE</strong> <em>(<var>x</var>, <var>l</var>)</em></dt>
<dt><a name="index-REAL_005fVALUE_005fTO_005fTARGET_005fDOUBLE"></a>Macro: <strong>REAL_VALUE_TO_TARGET_DOUBLE</strong> <em>(<var>x</var>, <var>l</var>)</em></dt>
<dt><a name="index-REAL_005fVALUE_005fTO_005fTARGET_005fLONG_005fDOUBLE"></a>Macro: <strong>REAL_VALUE_TO_TARGET_LONG_DOUBLE</strong> <em>(<var>x</var>, <var>l</var>)</em></dt>
<dt><a name="index-REAL_005fVALUE_005fTO_005fTARGET_005fDECIMAL32"></a>Macro: <strong>REAL_VALUE_TO_TARGET_DECIMAL32</strong> <em>(<var>x</var>, <var>l</var>)</em></dt>
<dt><a name="index-REAL_005fVALUE_005fTO_005fTARGET_005fDECIMAL64"></a>Macro: <strong>REAL_VALUE_TO_TARGET_DECIMAL64</strong> <em>(<var>x</var>, <var>l</var>)</em></dt>
<dt><a name="index-REAL_005fVALUE_005fTO_005fTARGET_005fDECIMAL128"></a>Macro: <strong>REAL_VALUE_TO_TARGET_DECIMAL128</strong> <em>(<var>x</var>, <var>l</var>)</em></dt>
<dd><p>These translate <var>x</var>, of type <code>REAL_VALUE_TYPE</code>, to the
target&rsquo;s floating point representation, and store its bit pattern in
the variable <var>l</var>.  For <code>REAL_VALUE_TO_TARGET_SINGLE</code> and
<code>REAL_VALUE_TO_TARGET_DECIMAL32</code>, this variable should be a
simple <code>long int</code>.  For the others, it should be an array of
<code>long int</code>.  The number of elements in this array is determined
by the size of the desired target floating point data type: 32 bits of
it go in each <code>long int</code> array element.  Each array element holds
32 bits of the result, even if <code>long int</code> is wider than 32 bits
on the host machine.
</p>
<p>The array element values are designed so that you can print them out
using <code>fprintf</code> in the order they should appear in the target
machine&rsquo;s memory.
</p></dd></dl>

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