<li><a href="#functionstructure">Functions</a></li>
<li><a href="#paramattrs">Parameter Attributes</a></li>
<li><a href="#moduleasm">Module-Level Inline Assembly</a></li>
+ <li><a href="#datalayout">Data Layout</a></li>
</ol>
</li>
<li><a href="#typesystem">Type System</a>
<li><a href="#t_pointer">Pointer Type</a></li>
<li><a href="#t_struct">Structure Type</a></li>
<li><a href="#t_pstruct">Packed Structure Type</a></li>
- <li><a href="#t_packed">Packed Type</a></li>
+ <li><a href="#t_vector">Vector Type</a></li>
<li><a href="#t_opaque">Opaque Type</a></li>
</ol>
</li>
</li>
<li><a href="#bitwiseops">Bitwise Binary Operations</a>
<ol>
- <li><a href="#i_and">'<tt>and</tt>' Instruction</a></li>
- <li><a href="#i_or">'<tt>or</tt>' Instruction</a></li>
- <li><a href="#i_xor">'<tt>xor</tt>' Instruction</a></li>
<li><a href="#i_shl">'<tt>shl</tt>' Instruction</a></li>
<li><a href="#i_lshr">'<tt>lshr</tt>' Instruction</a></li>
<li><a href="#i_ashr">'<tt>ashr</tt>' Instruction</a></li>
+ <li><a href="#i_and">'<tt>and</tt>' Instruction</a></li>
+ <li><a href="#i_or">'<tt>or</tt>' Instruction</a></li>
+ <li><a href="#i_xor">'<tt>xor</tt>' Instruction</a></li>
</ol>
</li>
<li><a href="#vectorops">Vector Operations</a>
prototype and implemented declaration of the function (as does normal C).
</dd>
- <dt><b>"<tt>csretcc</tt>" - The C struct return calling convention</b>:</dt>
-
- <dd>This calling convention matches the target C calling conventions, except
- that functions with this convention are required to take a pointer as their
- first argument, and the return type of the function must be void. This is
- used for C functions that return aggregates by-value. In this case, the
- function has been transformed to take a pointer to the struct as the first
- argument to the function. For targets where the ABI specifies specific
- behavior for structure-return calls, the calling convention can be used to
- distinguish between struct return functions and other functions that take a
- pointer to a struct as the first argument.
- </dd>
-
<dt><b>"<tt>fastcc</tt>" - The fast calling convention</b>:</dt>
<dd>This calling convention attempts to make calls as fast as possible
<dt><tt>sext</tt></dt>
<dd>This indicates that the parameter should be sign extended just before
a call to this function.</dd>
+ <dt><tt>inreg</tt></dt>
+ <dd>This indicates that the parameter should be placed in register (if
+ possible) during assembling function call. Support for this attribute is
+ target-specific</dd>
+ <dt><tt>sret</tt></dt>
+ <dd>This indicates that the parameter specifies the address of a structure
+ that is the return value of the function in the source program.
+ </dd>
</dl>
- <p>The current motivation for parameter attributes is to enable the sign and
- zero extend information necessary for the C calling convention to be passed
- from the front end to LLVM. The <tt>zext</tt> and <tt>sext</tt> attributes
- are used by the code generator to perform the required extension. However,
- parameter attributes are an orthogonal feature to calling conventions and
- may be used for other purposes in the future.</p>
</div>
<!-- ======================================================================= -->
</p>
</div>
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="datalayout">Data Layout</a>
+</div>
+
+<div class="doc_text">
+<p>A module may specify a target specific data layout string that specifies how
+data is to be laid out in memory. The syntax for the data layout is simply:<br/>
+<pre> target datalayout = "<i>layout specification</i>"
+</pre>
+The <i>layout specification</i> consists of a list of specifications separated
+by the minus sign character ('-'). Each specification starts with a letter
+and may include other information after the letter to define some aspect of the
+data layout. The specifications accepted are as follows: </p>
+<dl>
+ <dt><tt>E</tt></dt>
+ <dd>Specifies that the target lays out data in big-endian form. That is, the
+ bits with the most significance have the lowest address location.</dd>
+ <dt><tt>e</tt></dt>
+ <dd>Specifies that hte target lays out data in little-endian form. That is,
+ the bits with the least significance have the lowest address location.</dd>
+ <dt><tt>p:<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the <i>size</i> of a pointer and its <i>abi</i> and
+ <i>preferred</i> alignments. All sizes are in bits. Specifying the <i>pref</i>
+ alignment is optional. If omitted, the preceding <tt>:</tt> should be omitted
+ too.</dd>
+ <dt><tt>i<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the alignment for an integer type of a given bit
+ <i>size</i>. The value of <i>size</i> must be in the range [1,2^23).</dd>
+ <dt><tt>v<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the alignment for a vector type of a given bit
+ <i>size</i>.</dd>
+ <dt><tt>f<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the alignment for a floating point type of a given bit
+ <i>size</i>. The value of <i>size</i> must be either 32 (float) or 64
+ (double).</dd>
+ <dt><tt>a<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the alignment for an aggregate type of a given bit
+ <i>size</i>.</dd>
+</dl>
+<p>When constructing the data layout for a given target, LLVM starts with a
+default set of specifications which are then (possibly) overriden by the
+specifications in the <tt>datalayout</tt> keyword. The default specifications
+are given in this list:</p>
+<ul>
+ <li><tt>E</tt> - big endian</li>
+ <li><tt>p:32:64:64</tt> - 32-bit pointers with 64-bit alignment</li>
+ <li><tt>i1:8:8</tt> - i1 is 8-bit (byte) aligned</li>
+ <li><tt>i8:8:8</tt> - i8 is 8-bit (byte) aligned</li>
+ <li><tt>i16:16:16</tt> - i16 is 16-bit aligned</li>
+ <li><tt>i32:32:32</tt> - i32 is 32-bit aligned</li>
+ <li><tt>i64:32:64</tt> - i64 has abi alignment of 32-bits but preferred
+ alignment of 64-bits</li>
+ <li><tt>f32:32:32</tt> - float is 32-bit aligned</li>
+ <li><tt>f64:64:64</tt> - double is 64-bit aligned</li>
+ <li><tt>v64:64:64</tt> - 64-bit vector is 64-bit aligned</li>
+ <li><tt>v128:128:128</tt> - 128-bit vector is 128-bit aligned</li>
+ <li><tt>a0:0:1</tt> - aggregates are 8-bit aligned</li>
+</ul>
+<p>When llvm is determining the alignment for a given type, it uses the
+following rules:
+<ol>
+ <li>If the type sought is an exact match for one of the specifications, that
+ specification is used.</li>
+ <li>If no match is found, and the type sought is an integer type, then the
+ smallest integer type that is larger than the bitwidth of the sought type is
+ used. If none of the specifications are larger than the bitwidth then the the
+ largest integer type is used. For example, given the default specifications
+ above, the i7 type will use the alignment of i8 (next largest) while both
+ i65 and i256 will use the alignment of i64 (largest specified).</li>
+ <li>If no match is found, and the type sought is a vector type, then the
+ largest vector type that is smaller than the sought vector type will be used
+ as a fall back. This happens because <128 x double> can be implemented in
+ terms of 64 <2 x double>, for example.</li>
+</ol>
+</div>
<!-- *********************************************************************** -->
<div class="doc_section"> <a name="typesystem">Type System</a> </div>
<tr>
<td><a name="t_firstclass">first class</a></td>
<td><tt>i1, i8, i16, i32, i64, float, double, <br/>
- <a href="#t_pointer">pointer</a>,<a href="#t_packed">packed</a></tt>
+ <a href="#t_pointer">pointer</a>,<a href="#t_vector">vector</a></tt>
</td>
</tr>
</tbody>
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="t_packed">Packed Type</a> </div>
+<div class="doc_subsubsection"> <a name="t_vector">Vector Type</a> </div>
<div class="doc_text">
<h5>Overview:</h5>
-<p>A packed type is a simple derived type that represents a vector
-of elements. Packed types are used when multiple primitive data
+<p>A vector type is a simple derived type that represents a vector
+of elements. Vector types are used when multiple primitive data
are operated in parallel using a single instruction (SIMD).
-A packed type requires a size (number of
+A vector type requires a size (number of
elements) and an underlying primitive data type. Vectors must have a power
-of two length (1, 2, 4, 8, 16 ...). Packed types are
+of two length (1, 2, 4, 8, 16 ...). Vector types are
considered <a href="#t_firstclass">first class</a>.</p>
<h5>Syntax:</h5>
<tt><2 x i64></tt><br/>
</td>
<td class="left">
- Packed vector of 4 32-bit integer values.<br/>
- Packed vector of 8 floating-point values.<br/>
- Packed vector of 2 64-bit integer values.<br/>
+ Vector of 4 32-bit integer values.<br/>
+ Vector of 8 floating-point values.<br/>
+ Vector of 2 64-bit integer values.<br/>
</td>
</tr>
</table>
types of elements must match those specified by the type.
</dd>
- <dt><b>Packed constants</b></dt>
+ <dt><b>Vector constants</b></dt>
- <dd>Packed constants are represented with notation similar to packed type
+ <dd>Vector constants are represented with notation similar to vector type
definitions (a comma separated list of elements, surrounded by
less-than/greater-than's (<tt><></tt>)). For example: "<tt>< i32 42,
- i32 11, i32 74, i32 100 ></tt>".
Packed constants must have <a
- href="#t_packed">packed type</a>, and the number and types of elements must
+ i32 11, i32 74, i32 100 ></tt>".
VEctor constants must have <a
+ href="#t_vector">vector type</a>, and the number and types of elements must
match those specified by the type.
</dd>
identical (same number of bits). The conversion is done as if the CST value
was stored to memory and read back as TYPE. In other words, no bits change
with this operator, just the type. This can be used for conversion of
- packed types to any other type, as long as they have the same bit width. For
+ vector types to any other type, as long as they have the same bit width. For
pointers it is only valid to cast to another pointer type.
</dd>
<h5>Arguments:</h5>
<p>The conditional branch form of the '<tt>br</tt>' instruction takes a
single '<tt>i1</tt>' value and two '<tt>label</tt>' values. The
-unconditional form of the '<tt>br</tt>' instruction takes a single '<tt>label</tt>'
-value as a target.</p>
+unconditional form of the '<tt>br</tt>' instruction takes a single
+'<tt>label</tt>' value as a target.</p>
<h5>Semantics:</h5>
<p>Upon execution of a conditional '<tt>br</tt>' instruction, the '<tt>i1</tt>'
argument is evaluated. If the value is <tt>true</tt>, control flows
<p>Binary operators are used to do most of the computation in a
program. They require two operands, execute an operation on them, and
produce a single value. The operands might represent
-multiple data, as is the case with the <a href="#t_packed">packed</a> data type.
+multiple data, as is the case with the <a href="#t_vector">vector</a> data type.
The result value of a binary operator is not
necessarily the same type as its operands.</p>
<p>There are several different binary operators:</p>
<h5>Arguments:</h5>
<p>The two arguments to the '<tt>add</tt>' instruction must be either <a
href="#t_integer">integer</a> or <a href="#t_floating">floating point</a> values.
- This instruction can also take <a href="#t_packed">packed</a> versions of the values.
+ This instruction can also take <a href="#t_vector">vector</a> versions of the values.
Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the integer or floating point sum of the two
<p>The two arguments to the '<tt>sub</tt>' instruction must be either <a
href="#t_integer">integer</a> or <a href="#t_floating">floating point</a>
values.
-This instruction can also take <a href="#t_packed">packed</a> versions of the values.
+This instruction can also take <a href="#t_vector">vector</a> versions of the values.
Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the integer or floating point difference of
<p>The two arguments to the '<tt>mul</tt>' instruction must be either <a
href="#t_integer">integer</a> or <a href="#t_floating">floating point</a>
values.
-This instruction can also take <a href="#t_packed">packed</a> versions of the values.
+This instruction can also take <a href="#t_vector">vector</a> versions of the values.
Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the integer or floating point product of the
<h5>Arguments:</h5>
<p>The two arguments to the '<tt>udiv</tt>' instruction must be
<a href="#t_integer">integer</a> values. Both arguments must have identical
-types. This instruction can also take <a href="#t_packed">packed</a> versions
+types. This instruction can also take <a href="#t_vector">vector</a> versions
of the values in which case the elements must be integers.</p>
<h5>Semantics:</h5>
<p>The value produced is the unsigned integer quotient of the two operands. This
<h5>Arguments:</h5>
<p>The two arguments to the '<tt>sdiv</tt>' instruction must be
<a href="#t_integer">integer</a> values. Both arguments must have identical
-types. This instruction can also take <a href="#t_packed">packed</a> versions
+types. This instruction can also take <a href="#t_vector">vector</a> versions
of the values in which case the elements must be integers.</p>
<h5>Semantics:</h5>
<p>The value produced is the signed integer quotient of the two operands. This
<h5>Arguments:</h5>
<p>The two arguments to the '<tt>div</tt>' instruction must be
<a href="#t_floating">floating point</a> values. Both arguments must have
-identical types. This instruction can also take <a href="#t_packed">packed</a>
+identical types. This instruction can also take <a href="#t_vector">vector</a>
versions of the values in which case the elements must be floating point.</p>
<h5>Semantics:</h5>
<p>The value produced is the floating point quotient of the two operands.</p>
and produce a single value. The resulting value of the bitwise binary
operators is always the same type as its first operand.</p>
</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_shl">'<tt>shl</tt>'
+Instruction</a> </div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = shl <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+</pre>
+<h5>Overview:</h5>
+<p>The '<tt>shl</tt>' instruction returns the first operand shifted to
+the left a specified number of bits.</p>
+<h5>Arguments:</h5>
+<p>Both arguments to the '<tt>shl</tt>' instruction must be the same <a
+ href="#t_integer">integer</a> type.</p>
+<h5>Semantics:</h5>
+<p>The value produced is <tt>var1</tt> * 2<sup><tt>var2</tt></sup>.</p>
+<h5>Example:</h5><pre>
+ <result> = shl i32 4, %var <i>; yields {i32}: 4 << %var</i>
+ <result> = shl i32 4, 2 <i>; yields {i32}: 16</i>
+ <result> = shl i32 1, 10 <i>; yields {i32}: 1024</i>
+</pre>
+</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_lshr">'<tt>lshr</tt>'
+Instruction</a> </div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = lshr <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>lshr</tt>' instruction (logical shift right) returns the first
+operand shifted to the right a specified number of bits.</p>
+
+<h5>Arguments:</h5>
+<p>Both arguments to the '<tt>lshr</tt>' instruction must be the same
+<a href="#t_integer">integer</a> type.</p>
+
+<h5>Semantics:</h5>
+<p>This instruction always performs a logical shift right operation. The most
+significant bits of the result will be filled with zero bits after the
+shift.</p>
+
+<h5>Example:</h5>
+<pre>
+ <result> = lshr i32 4, 1 <i>; yields {i32}:result = 2</i>
+ <result> = lshr i32 4, 2 <i>; yields {i32}:result = 1</i>
+ <result> = lshr i8 4, 3 <i>; yields {i8}:result = 0</i>
+ <result> = lshr i8 -2, 1 <i>; yields {i8}:result = 0x7FFFFFFF </i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_ashr">'<tt>ashr</tt>'
+Instruction</a> </div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre> <result> = ashr <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>ashr</tt>' instruction (arithmetic shift right) returns the first
+operand shifted to the right a specified number of bits.</p>
+
+<h5>Arguments:</h5>
+<p>Both arguments to the '<tt>ashr</tt>' instruction must be the same
+<a href="#t_integer">integer</a> type.</p>
+
+<h5>Semantics:</h5>
+<p>This instruction always performs an arithmetic shift right operation,
+The most significant bits of the result will be filled with the sign bit
+of <tt>var1</tt>.</p>
+
+<h5>Example:</h5>
+<pre>
+ <result> = ashr i32 4, 1 <i>; yields {i32}:result = 2</i>
+ <result> = ashr i32 4, 2 <i>; yields {i32}:result = 1</i>
+ <result> = ashr i8 4, 3 <i>; yields {i8}:result = 0</i>
+ <result> = ashr i8 -2, 1 <i>; yields {i8}:result = -1</i>
+</pre>
+</div>
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="i_and">'<tt>and</tt>'
Instruction</a> </div>
<result> = xor i32 %V, -1 <i>; yields {i32}:result = ~%V</i>
</pre>
</div>
-<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_shl">'<tt>shl</tt>'
-Instruction</a> </div>
-<div class="doc_text">
-<h5>Syntax:</h5>
-<pre> <result> = shl <ty> <var1>, i8 <var2> <i>; yields {ty}:result</i>
-</pre>
-<h5>Overview:</h5>
-<p>The '<tt>shl</tt>' instruction returns the first operand shifted to
-the left a specified number of bits.</p>
-<h5>Arguments:</h5>
-<p>The first argument to the '<tt>shl</tt>' instruction must be an <a
- href="#t_integer">integer</a> type. The second argument must be an '<tt>i8</tt>'
-type.</p>
-<h5>Semantics:</h5>
-<p>The value produced is <tt>var1</tt> * 2<sup><tt>var2</tt></sup>.</p>
-<h5>Example:</h5>
-<pre> <result> = shl i32 4, i8 %var <i>; yields {i32}:result = 4 << %var</i>
- <result> = shl i32 4, i8 2 <i>; yields {i32}:result = 16</i>
- <result> = shl i32 1, i8 10 <i>; yields {i32}:result = 1024</i>
-</pre>
-</div>
-<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_lshr">'<tt>lshr</tt>'
-Instruction</a> </div>
-<div class="doc_text">
-<h5>Syntax:</h5>
-<pre> <result> = lshr <ty> <var1>, i8 <var2> <i>; yields {ty}:result</i>
-</pre>
-
-<h5>Overview:</h5>
-<p>The '<tt>lshr</tt>' instruction (logical shift right) returns the first
-operand shifted to the right a specified number of bits.</p>
-
-<h5>Arguments:</h5>
-<p>The first argument to the '<tt>lshr</tt>' instruction must be an <a
- href="#t_integer">integer</a> type. The second argument must be an '<tt>i8</tt>' type.</p>
-
-<h5>Semantics:</h5>
-<p>This instruction always performs a logical shift right operation. The
-<tt>var2</tt> most significant bits will be filled with zero bits after the
-shift.</p>
-
-<h5>Example:</h5>
-<pre>
- <result> = lshr i32 4, i8 1 <i>; yields {i32}:result = 2</i>
- <result> = lshr i32 4, i8 2 <i>; yields {i32}:result = 1</i>
- <result> = lshr i8 4, i8 3 <i>; yields {i8 }:result = 0</i>
- <result> = lshr i8 -2, i8 1 <i>; yields {i8 }:result = 0x7FFFFFFF </i>
-</pre>
-</div>
-
-<!-- ======================================================================= -->
-<div class="doc_subsubsection"> <a name="i_ashr">'<tt>ashr</tt>'
-Instruction</a> </div>
-<div class="doc_text">
-
-<h5>Syntax:</h5>
-<pre> <result> = ashr <ty> <var1>, i8 <var2> <i>; yields {ty}:result</i>
-</pre>
-
-<h5>Overview:</h5>
-<p>The '<tt>ashr</tt>' instruction (arithmetic shift right) returns the first
-operand shifted to the right a specified number of bits.</p>
-
-<h5>Arguments:</h5>
-<p>The first argument to the '<tt>ashr</tt>' instruction must be an
-<a href="#t_integer">integer</a> type. The second argument must be an
-'<tt>i8</tt>' type.</p>
-
-<h5>Semantics:</h5>
-<p>This instruction always performs an arithmetic shift right operation,
-regardless of whether the arguments are signed or not. The <tt>var2</tt> most
-significant bits will be filled with the sign bit of <tt>var1</tt>.</p>
-
-<h5>Example:</h5>
-<pre>
- <result> = ashr i32 4, i8 1 <i>; yields {i32}:result = 2</i>
- <result> = ashr i32 4, i8 2 <i>; yields {i32}:result = 1</i>
- <result> = ashr i8 4, i8 3 <i>; yields {i8}:result = 0</i>
- <result> = ashr i8 -2, i8 1 <i>; yields {i8 }:result = -1</i>
-</pre>
-</div>
<!-- ======================================================================= -->
<div class="doc_subsection">
<p>
The '<tt>extractelement</tt>' instruction extracts a single scalar
-element from a packed vector at a specified index.
+element from a vector at a specified index.
</p>
<p>
The first operand of an '<tt>extractelement</tt>' instruction is a
-value of <a href="#t_packed">packed</a> type. The second operand is
+value of <a href="#t_vector">vector</a> type. The second operand is
an index indicating the position from which to extract the element.
The index may be a variable.</p>
<p>
The '<tt>insertelement</tt>' instruction inserts a scalar
-element into a packed vector at a specified index.
+element into a vector at a specified index.
</p>
<p>
The first operand of an '<tt>insertelement</tt>' instruction is a
-value of <a href="#t_packed">packed</a> type. The second operand is a
+value of <a href="#t_vector">vector</a> type. The second operand is a
scalar value whose type must equal the element type of the first
operand. The third operand is an index indicating the position at
which to insert the value. The index may be a variable.</p>
<h5>Semantics:</h5>
<p>
-The result is a packed vector of the same type as <tt>val</tt>. Its
+The result is a vector of the same type as <tt>val</tt>. Its
element values are those of <tt>val</tt> except at position
<tt>idx</tt>, where it gets the value <tt>elt</tt>. If <tt>idx</tt>
exceeds the length of <tt>val</tt>, the results are undefined.
projects / oota-llvm.git / blobdiff