mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-15 04:30:12 +00:00
rearrange some info about the instruction encoding
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24204 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner
parent
42ba6b4b88
commit
f97fa59313
@ -39,8 +39,8 @@
|
|||||||
<li><a href="#constantpool">Global Constant Pool</a></li>
|
<li><a href="#constantpool">Global Constant Pool</a></li>
|
||||||
<li><a href="#functiondefs">Function Definition</a></li>
|
<li><a href="#functiondefs">Function Definition</a></li>
|
||||||
<li><a href="#compactiontable">Compaction Table</a></li>
|
<li><a href="#compactiontable">Compaction Table</a></li>
|
||||||
<li><a href="#instructionlist">Instruction List</a></li>
|
<li><a href="#instructionlist">Instructions List</a></li>
|
||||||
<li><a href="#opcodes">Instruction Opcodes</a></li>
|
<li><a href="#instructions">Instructions</a></li>
|
||||||
<li><a href="#symtab">Symbol Table</a></li>
|
<li><a href="#symtab">Symbol Table</a></li>
|
||||||
</ol>
|
</ol>
|
||||||
</li>
|
</li>
|
||||||
@ -1363,186 +1363,23 @@ of formats. See <a href="#instruction">Instructions</a> for details.</td>
|
|||||||
</tbody>
|
</tbody>
|
||||||
</table>
|
</table>
|
||||||
</div>
|
</div>
|
||||||
|
|
||||||
<!-- _______________________________________________________________________ -->
|
<!-- _______________________________________________________________________ -->
|
||||||
<div class="doc_subsubsection"><a name="instruction">Instructions</a></div>
|
<div class="doc_subsection"><a name="instructions">Instructions</a></div>
|
||||||
|
|
||||||
<div class="doc_text">
|
<div class="doc_text">
|
||||||
<p>For brevity, instructions are written in one of four formats,
|
<p>Instructions are written out one at a time as distinct units. Each
|
||||||
depending on the number of operands to the instruction. Each
|
instruction
|
||||||
instruction begins with a <a href="#uint32_vbr">uint32_vbr</a> that
|
record contains at least an <a href="#opcodes">opcode</a> and a type field,
|
||||||
encodes the type of the instruction as well as other things. The tables
|
and may contain a list of operands (whose interpretation depends on the opcode).
|
||||||
that follow describe the format of this first part of each instruction.</p>
|
Based on the number of operands, the
|
||||||
<p><b>Instruction Format 0</b></p>
|
<a href="#instencode">instruction is encoded</a> in a
|
||||||
<p>This format is used for a few instructions that can't easily be
|
dense format that tries to encoded each instruction into 32-bits if
|
||||||
shortened because they have large numbers of operands (e.g. PHI Node or
|
possible. </p>
|
||||||
getelementptr). Each of the opcode, type, and operand fields is found in
|
|
||||||
successive fields.</p>
|
|
||||||
<table>
|
|
||||||
<tbody>
|
|
||||||
<tr>
|
|
||||||
<th><b>Type</b></th>
|
|
||||||
<th class="td_left"><b>Field Description</b></th>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td><a href="#uint32_vbr">uint32_vbr</a></td>
|
|
||||||
<td class="td_left">Specifies the opcode of the instruction. Note
|
|
||||||
that for compatibility with the other instruction formats, the opcode
|
|
||||||
is shifted left by 2 bits. Bits 0 and 1 must have value zero for this
|
|
||||||
format.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td><a href="#uint24_vbr">uint24_vbr</a></td>
|
|
||||||
<td class="td_left">Provides the type slot number of the result type of
|
|
||||||
the instruction.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td><a href="#uint32_vbr">uint32_vbr</a></td>
|
|
||||||
<td class="td_left">The number of operands that follow.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td><a href="#uint32_vbr">uint32_vbr</a>+</td>
|
|
||||||
<td class="td_left">The slot number of the value(s) for the operand(s).
|
|
||||||
<sup>1</sup></td>
|
|
||||||
</tr>
|
|
||||||
</tbody>
|
|
||||||
</table>
|
|
||||||
Notes:
|
|
||||||
<ol>
|
|
||||||
<li>Note that if the instruction is a getelementptr and the type of
|
|
||||||
the operand is a sequential type (array or pointer) then the slot
|
|
||||||
number is shifted up two bits and the low order bits will encode the
|
|
||||||
type of index used, as follows: 0=uint, 1=int, 2=ulong, 3=long.</li>
|
|
||||||
</ol>
|
|
||||||
<p><b>Instruction Format 1</b></p>
|
|
||||||
<p>This format encodes the opcode, type and a single operand into a
|
|
||||||
single <a href="#uint32_vbr">uint32_vbr</a> as follows:</p>
|
|
||||||
<table>
|
|
||||||
<tbody>
|
|
||||||
<tr>
|
|
||||||
<th><b>Bits</b></th>
|
|
||||||
<th><b>Type</b></th>
|
|
||||||
<th class="td_left"><b>Field Description</b></th>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>0-1</td>
|
|
||||||
<td>constant "1"</td>
|
|
||||||
<td class="td_left">These two bits must be the value 1 which identifies
|
|
||||||
this as an instruction of format 1.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>2-7</td>
|
|
||||||
<td><a href="#opcode">opcode</a></td>
|
|
||||||
<td class="td_left">Specifies the opcode of the instruction. Note that
|
|
||||||
the maximum opcode value is 63.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>8-19</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the type for this
|
|
||||||
instruction. Maximum slot number is 2<sup>12</sup>-1=4095.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>20-31</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the value for the
|
|
||||||
first operand. Maximum slot number is 2<sup>12</sup>-1=4095. Note that
|
|
||||||
the value 2<sup>12</sup>-1 denotes zero operands.</td>
|
|
||||||
</tr>
|
|
||||||
</tbody>
|
|
||||||
</table>
|
|
||||||
<p><b>Instruction Format 2</b></p>
|
|
||||||
<p>This format encodes the opcode, type and two operands into a single <a
|
|
||||||
href="#uint32_vbr">uint32_vbr</a> as follows:</p>
|
|
||||||
<table>
|
|
||||||
<tbody>
|
|
||||||
<tr>
|
|
||||||
<th><b>Bits</b></th>
|
|
||||||
<th><b>Type</b></th>
|
|
||||||
<th class="td_left"><b>Field Description</b></th>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>0-1</td>
|
|
||||||
<td>constant "2"</td>
|
|
||||||
<td class="td_left">These two bits must be the value 2 which identifies
|
|
||||||
this as an instruction of format 2.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>2-7</td>
|
|
||||||
<td><a href="#opcodes">opcode</a></td>
|
|
||||||
<td class="td_left">Specifies the opcode of the instruction. Note that
|
|
||||||
the maximum opcode value is 63.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>8-15</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the type for this
|
|
||||||
instruction. Maximum slot number is 2<sup>8</sup>-1=255.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>16-23</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the value for the first
|
|
||||||
operand. Maximum slot number is 2<sup>8</sup>-1=255.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>24-31</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the value for the second
|
|
||||||
operand. Maximum slot number is 2<sup>8</sup>-1=255.</td>
|
|
||||||
</tr>
|
|
||||||
</tbody>
|
|
||||||
</table>
|
|
||||||
<p><b>Instruction Format 3</b></p>
|
|
||||||
<p>This format encodes the opcode, type and three operands into a
|
|
||||||
single <a href="#uint32_vbr">uint32_vbr</a> as follows:</p>
|
|
||||||
<table>
|
|
||||||
<tbody>
|
|
||||||
<tr>
|
|
||||||
<th><b>Bits</b></th>
|
|
||||||
<th><b>Type</b></th>
|
|
||||||
<th class="td_left"><b>Field Description</b></th>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>0-1</td>
|
|
||||||
<td>constant "3"</td>
|
|
||||||
<td class="td_left">These two bits must be the value 3 which identifies
|
|
||||||
this as an instruction of format 3.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>2-7</td>
|
|
||||||
<td><a href="#opcodes">opcode</a></td>
|
|
||||||
<td class="td_left">Specifies the opcode of the instruction. Note that
|
|
||||||
the maximum opcode value is 63.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>8-13</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the type for this
|
|
||||||
instruction. Maximum slot number is 2<sup>6</sup>-1=63.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>14-19</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the value for the first
|
|
||||||
operand. Maximum slot number is 2<sup>6</sup>-1=63.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>20-25</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the value for the second
|
|
||||||
operand. Maximum slot number is 2<sup>6</sup>-1=63.</td>
|
|
||||||
</tr>
|
|
||||||
<tr>
|
|
||||||
<td>26-31</td>
|
|
||||||
<td><a href="#unsigned">unsigned</a></td>
|
|
||||||
<td class="td_left">Specifies the slot number of the value for the third
|
|
||||||
operand. Maximum slot number is 2<sup>6</sup>-1=63.</td>
|
|
||||||
</tr>
|
|
||||||
</tbody>
|
|
||||||
</table>
|
|
||||||
</div>
|
</div>
|
||||||
|
|
||||||
<!-- _______________________________________________________________________ -->
|
<!-- _______________________________________________________________________ -->
|
||||||
<div class="doc_subsection"><a name="opcodes">Instruction Opcodes</a></div>
|
<div class="doc_subsubsection"><a name="opcodes">Instruction Opcodes</a></div>
|
||||||
<div class="doc_text">
|
<div class="doc_text">
|
||||||
<p>Instructions encode an opcode that identifies the kind of instruction.
|
<p>Instructions encode an opcode that identifies the kind of instruction.
|
||||||
Opcodes are an enumerated integer value. The specific values used depend on
|
Opcodes are an enumerated integer value. The specific values used depend on
|
||||||
@ -1614,10 +1451,9 @@ single <a href="#uint32_vbr">uint32_vbr</a> as follows:</p>
|
|||||||
<tr><td>Store+Volatile</td><td>63</td><td>3</td><td>1.3</td></tr>
|
<tr><td>Store+Volatile</td><td>63</td><td>3</td><td>1.3</td></tr>
|
||||||
</tbody>
|
</tbody>
|
||||||
</table>
|
</table>
|
||||||
</div>
|
|
||||||
|
|
||||||
<p><b><a name="pi_note">* Note: </a></b>
|
<p><b><a name="pi_note">* Note: </a></b>
|
||||||
These aren't really opcodes from an LLVM language prespeective. They encode
|
These aren't really opcodes from an LLVM language perspective. They encode
|
||||||
information into other opcodes without reserving space for that information.
|
information into other opcodes without reserving space for that information.
|
||||||
For example, opcode=63 is a Volatile Store. The opcode for this
|
For example, opcode=63 is a Volatile Store. The opcode for this
|
||||||
instruction is 25 (Store) but we encode it as 63 to indicate that is a Volatile
|
instruction is 25 (Store) but we encode it as 63 to indicate that is a Volatile
|
||||||
@ -1639,6 +1475,188 @@ opcode (Invoke, Call, Store) plus some set of modifiers, as follows:</p>
|
|||||||
<dt>TailCall</dt>
|
<dt>TailCall</dt>
|
||||||
<dd>This indicates that the Call has the 'tail' modifier.</dd>
|
<dd>This indicates that the Call has the 'tail' modifier.</dd>
|
||||||
</dl>
|
</dl>
|
||||||
|
</div>
|
||||||
|
|
||||||
|
|
||||||
|
<!-- _______________________________________________________________________ -->
|
||||||
|
<div class="doc_subsubsection"><a name="instencode">Instruction
|
||||||
|
Encoding</a></div>
|
||||||
|
|
||||||
|
<div class="doc_text">
|
||||||
|
<p>For brevity, instructions are written in one of four formats,
|
||||||
|
depending on the number of operands to the instruction. Each
|
||||||
|
instruction begins with a <a href="#uint32_vbr">uint32_vbr</a> that
|
||||||
|
encodes the type of the instruction as well as other things. The tables
|
||||||
|
that follow describe the format of this first part of each instruction.</p>
|
||||||
|
<p><b>Instruction Format 0</b></p>
|
||||||
|
<p>This format is used for a few instructions that can't easily be
|
||||||
|
shortened because they have large numbers of operands (e.g. PHI Node or
|
||||||
|
getelementptr). Each of the opcode, type, and operand fields is found in
|
||||||
|
successive fields.</p>
|
||||||
|
<table>
|
||||||
|
<tbody>
|
||||||
|
<tr>
|
||||||
|
<th><b>Type</b></th>
|
||||||
|
<th class="td_left"><b>Field Description</b></th>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td><a href="#uint32_vbr">uint32_vbr</a></td>
|
||||||
|
<td class="td_left">Specifies the opcode of the instruction. Note
|
||||||
|
that for compatibility with the other instruction formats, the opcode
|
||||||
|
is shifted left by 2 bits. Bits 0 and 1 must have value zero for this
|
||||||
|
format.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td><a href="#uint24_vbr">uint24_vbr</a></td>
|
||||||
|
<td class="td_left">Provides the type slot number of the result type of
|
||||||
|
the instruction.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td><a href="#uint32_vbr">uint32_vbr</a></td>
|
||||||
|
<td class="td_left">The number of operands that follow.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td><a href="#uint32_vbr">uint32_vbr</a>+</td>
|
||||||
|
<td class="td_left">The slot number of the value(s) for the operand(s).
|
||||||
|
<sup>1</sup></td>
|
||||||
|
</tr>
|
||||||
|
</tbody>
|
||||||
|
</table>
|
||||||
|
Notes:
|
||||||
|
<ol>
|
||||||
|
<li>Note that if the instruction is a getelementptr and the type of
|
||||||
|
the operand is a sequential type (array or pointer) then the slot
|
||||||
|
number is shifted up two bits and the low order bits will encode the
|
||||||
|
type of index used, as follows: 0=uint, 1=int, 2=ulong, 3=long.</li>
|
||||||
|
</ol>
|
||||||
|
<p><b>Instruction Format 1</b></p>
|
||||||
|
<p>This format encodes the opcode, type and a single operand into a
|
||||||
|
single <a href="#uint32_vbr">uint32_vbr</a> as follows:</p>
|
||||||
|
<table>
|
||||||
|
<tbody>
|
||||||
|
<tr>
|
||||||
|
<th><b>Bits</b></th>
|
||||||
|
<th><b>Type</b></th>
|
||||||
|
<th class="td_left"><b>Field Description</b></th>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>0-1</td>
|
||||||
|
<td>constant "1"</td>
|
||||||
|
<td class="td_left">These two bits must be the value 1 which identifies
|
||||||
|
this as an instruction of format 1.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>2-7</td>
|
||||||
|
<td><a href="#instructions">opcode</a></td>
|
||||||
|
<td class="td_left">Specifies the opcode of the instruction. Note that
|
||||||
|
the maximum opcode value is 63.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>8-19</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the type for this
|
||||||
|
instruction. Maximum slot number is 2<sup>12</sup>-1=4095.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>20-31</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the value for the
|
||||||
|
first operand. Maximum slot number is 2<sup>12</sup>-1=4095. Note that
|
||||||
|
the value 2<sup>12</sup>-1 denotes zero operands.</td>
|
||||||
|
</tr>
|
||||||
|
</tbody>
|
||||||
|
</table>
|
||||||
|
<p><b>Instruction Format 2</b></p>
|
||||||
|
<p>This format encodes the opcode, type and two operands into a single <a
|
||||||
|
href="#uint32_vbr">uint32_vbr</a> as follows:</p>
|
||||||
|
<table>
|
||||||
|
<tbody>
|
||||||
|
<tr>
|
||||||
|
<th><b>Bits</b></th>
|
||||||
|
<th><b>Type</b></th>
|
||||||
|
<th class="td_left"><b>Field Description</b></th>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>0-1</td>
|
||||||
|
<td>constant "2"</td>
|
||||||
|
<td class="td_left">These two bits must be the value 2 which identifies
|
||||||
|
this as an instruction of format 2.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>2-7</td>
|
||||||
|
<td><a href="#instructions">opcode</a></td>
|
||||||
|
<td class="td_left">Specifies the opcode of the instruction. Note that
|
||||||
|
the maximum opcode value is 63.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>8-15</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the type for this
|
||||||
|
instruction. Maximum slot number is 2<sup>8</sup>-1=255.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>16-23</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the value for the first
|
||||||
|
operand. Maximum slot number is 2<sup>8</sup>-1=255.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>24-31</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the value for the second
|
||||||
|
operand. Maximum slot number is 2<sup>8</sup>-1=255.</td>
|
||||||
|
</tr>
|
||||||
|
</tbody>
|
||||||
|
</table>
|
||||||
|
<p><b>Instruction Format 3</b></p>
|
||||||
|
<p>This format encodes the opcode, type and three operands into a
|
||||||
|
single <a href="#uint32_vbr">uint32_vbr</a> as follows:</p>
|
||||||
|
<table>
|
||||||
|
<tbody>
|
||||||
|
<tr>
|
||||||
|
<th><b>Bits</b></th>
|
||||||
|
<th><b>Type</b></th>
|
||||||
|
<th class="td_left"><b>Field Description</b></th>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>0-1</td>
|
||||||
|
<td>constant "3"</td>
|
||||||
|
<td class="td_left">These two bits must be the value 3 which identifies
|
||||||
|
this as an instruction of format 3.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>2-7</td>
|
||||||
|
<td><a href="#instructions">opcode</a></td>
|
||||||
|
<td class="td_left">Specifies the opcode of the instruction. Note that
|
||||||
|
the maximum opcode value is 63.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>8-13</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the type for this
|
||||||
|
instruction. Maximum slot number is 2<sup>6</sup>-1=63.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>14-19</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the value for the first
|
||||||
|
operand. Maximum slot number is 2<sup>6</sup>-1=63.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>20-25</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the value for the second
|
||||||
|
operand. Maximum slot number is 2<sup>6</sup>-1=63.</td>
|
||||||
|
</tr>
|
||||||
|
<tr>
|
||||||
|
<td>26-31</td>
|
||||||
|
<td><a href="#unsigned">unsigned</a></td>
|
||||||
|
<td class="td_left">Specifies the slot number of the value for the third
|
||||||
|
operand. Maximum slot number is 2<sup>6</sup>-1=63.</td>
|
||||||
|
</tr>
|
||||||
|
</tbody>
|
||||||
|
</table>
|
||||||
|
</div>
|
||||||
|
|
||||||
<!-- _______________________________________________________________________ -->
|
<!-- _______________________________________________________________________ -->
|
||||||
<div class="doc_subsection"><a name="symtab">Symbol Table</a> </div>
|
<div class="doc_subsection"><a name="symtab">Symbol Table</a> </div>
|
||||||
|
|||||||
Loading…
Reference in New Issue
Block a user