r340021 - [ThinLTO] Correct documentation on default number of threads

[Teresa Johnson via cfe-commits]

Author: tejohnson
Date: Fri Aug 17 06:19:36 2018
New Revision: 340021

URL: http://llvm.org/viewvc/llvm-project?rev=340021&view=rev
Log:
[ThinLTO] Correct documentation on default number of threads

Summary:
The number of threads used for ThinLTO backend parallelism was
dropped to the number of cores in r284618 to avoid oversubscribing
physical cores due to hyperthreading. This updates the documentation
to reflect that change.

Fixes PR38610.

Reviewers: pcc

Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D50882

Modified:
    cfe/trunk/docs/ThinLTO.rst

Modified: cfe/trunk/docs/ThinLTO.rst
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/docs/ThinLTO.rst?rev=340021&r1=340020&r2=340021&view=diff
==============================================================================
--- cfe/trunk/docs/ThinLTO.rst (original)
+++ cfe/trunk/docs/ThinLTO.rst Fri Aug 17 06:19:36 2018
@@ -105,7 +105,9 @@ Controlling Backend Parallelism
 -------------------------------
 .. _parallelism:
 
-By default, the ThinLTO link step will launch up to
+By default, the ThinLTO link step will launch as many
+threads in parallel as there are cores. If the number of
+cores can't be computed for the architecture, then it will launch
 ``std::thread::hardware_concurrency`` number of threads in parallel.
 For machines with hyper-threading, this is the total number of
 virtual cores. For some applications and machine configurations this