Add DEBUG_WITH_TYPE as a clean alternative to tweaking DEBUG_TYPE.

This:
--
#undef DEBUG_TYPE
#define DEBUG_TYPE "foo"
DEBUG(...)
#undef DEBUG_TYPE
#define DEBUG_TYPE ""
--
becomes this:
--
DEBUG_WITH_TYPE("foo", ...)
--


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78435 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/ProgrammersManual.html b/docs/ProgrammersManual.html
index e3f91a2..e920cbb 100644
--- a/docs/ProgrammersManual.html
+++ b/docs/ProgrammersManual.html
@@ -646,6 +646,21 @@
 for instruction scheduling to be enabled with <tt>-debug-type=InstrSched</tt>,
 even if the source lives in multiple files.</p>
 
+<p>The <tt>DEBUG_WITH_TYPE</tt> macro is also available for situations where you
+would like to set <tt>DEBUG_TYPE</tt>, but only for one specific <tt>DEBUG</tt>
+statement. It takes an additional first parameter, which is the type to use. For
+example, the preceeding example could be written as:</p>
+
+
+<div class="doc_code">
+<pre>
+DEBUG_WITH_TYPE("", errs() &lt;&lt; "No debug type\n");
+DEBUG_WITH_TYPE("foo", errs() &lt;&lt; "'foo' debug type\n");
+DEBUG_WITH_TYPE("bar", errs() &lt;&lt; "'bar' debug type\n"));
+DEBUG_WITH_TYPE("", errs() &lt;&lt; "No debug type (2)\n");
+</pre>
+</div>
+
 </div>
 
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