r352818 - [sanitizer-coverage] prune trace-cmp instrumentation for CMP isntructions that feed into the backedge branch. Instrumenting these CMP instructions is almost always useless (and harmful) for fuzzing

[Kostya Serebryany via cfe-commits]

Author: kcc
Date: Thu Jan 31 15:43:00 2019
New Revision: 352818

URL: http://llvm.org/viewvc/llvm-project?rev=352818&view=rev
Log:
[sanitizer-coverage] prune trace-cmp instrumentation for CMP isntructions that feed into the backedge branch. Instrumenting these CMP instructions is almost always useless (and harmful) for fuzzing

Modified:
    cfe/trunk/docs/SanitizerCoverage.rst

Modified: cfe/trunk/docs/SanitizerCoverage.rst
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/docs/SanitizerCoverage.rst?rev=352818&r1=352817&r2=352818&view=diff
==============================================================================
--- cfe/trunk/docs/SanitizerCoverage.rst (original)
+++ cfe/trunk/docs/SanitizerCoverage.rst Thu Jan 31 15:43:00 2019
@@ -248,6 +248,9 @@ and with  ``-fsanitize-coverage=trace-ge
 the `LLVM GEP instructions <https://llvm.org/docs/GetElementPtr.html>`_
 (to capture array indices).
 
+Unless ``no-prune`` option is provided, some of the comparison instructions
+will not be instrumented.
+
 .. code-block:: c++
 
   // Called before a comparison instruction.