6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-03-01 01:30:36 +00:00
Code Issues Projects Releases Wiki Activity

Document the pseudo-instruction opcodes in opcode range 56-63. These are

Browse Source 
used to support things like volatile load/store, tail calls, and calling
conventions without reserving space for the additional information.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21996 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Reid Spencer 2005-05-14 00:06:06 +00:00
parent 10d2645710
commit a5681773ab
1 changed files with 36 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
docs/BytecodeFormat.html
View File

@ -1601,10 +1601,46 @@ single <a href="#uint32_vbr">uint32_vbr</a> as follows:</p>
<tr><td>Select</td><td>34</td><td>2</td><td>1.2</td></tr>
<tr><td>UserOp1</td><td>35</td><td>1</td><td>1.0</td></tr>
<tr><td>UserOp2</td><td>36</td><td>1</td><td>1.0</td></tr>
<tr><td colspan="4">
<b>Pseudo Instructions<a href="#pi_note">*</a></b>
</td></tr>
<tr><td>Invoke+CC </td><td>56</td><td>5</td><td>1.5</td></tr>
<tr><td>Invoke+FastCC</td><td>57</td><td>5</td><td>1.5</td></tr>
<tr><td>Call+CC</td><td>58</td><td>5</td><td>1.5</td></tr>
<tr><td>Call+FastCC+TailCall</td><td>59</td><td>5</td><td>1.5</td></tr>
<tr><td>Call+FastCC</td><td>60</td><td>5</td><td>1.5</td></tr>
<tr><td>Call+CCC+TailCall</td><td>61</td><td>5</td><td>1.5</td></tr>
<tr><td>Load+Volatile</td><td>62</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>
</table>
</div>
<p><b><a name="pi_note">* Note: </a></b>
These aren't really opcodes from an LLVM language prespeective. They encode
information into other opcodes without reserving space for that information.
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
Store. The same is done for the calling conventions and tail calls.
In each of these entries in range 56-63, the opcode is documented as the base
opcode (Invoke, Call, Store) plus some set of modifiers, as follows:</p>
<dl>
<dt>CC</dt>
<dd>This means a generic (user defined) calling convention number is specified
in a VBR that follows the opcode immediately. This is used when the calling
convention for the Invoke or the Call instruction is not one of the LLVM
standard ones (like FastCC or CCC)
</dd>
<dt>FastCC</dt>
<dd>This indicates that the Call or Invoke is using the FastCC calling
convention which puts arguments in registers to avoid stack loading.</dd>
<dt>CCC</dt>
<dd>This indicates that the Call or Invoke is using the "C" calling convention
which is specified by the C99 language.</dd>
<dt>TailCall</dt>
<dd>This indicates that the Call or Invoke is a tail call.</dd>
</dl>
<!-- _______________________________________________________________________ -->
<div class="doc_subsection"><a name="symtab">Symbol Table</a> </div>
<div class="doc_text">