[llvm] r325439 - [X86] Add 'sahf' to getHostCPUFeatures so -march=native will pick it up correctly.

[Craig Topper via llvm-commits]

Author: ctopper
Date: Sat Feb 17 08:52:49 2018
New Revision: 325439

URL: http://llvm.org/viewvc/llvm-project?rev=325439&view=rev
Log:
[X86] Add 'sahf' to getHostCPUFeatures so -march=native will pick it up correctly.

Summary: We probably mostly get this right due to family/model/stepping mapping to CPU names. But we should detect it explicitly.

Reviewers: RKSimon, echristo, dim, spatel

Reviewed By: dim

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43418

Modified:
    llvm/trunk/lib/Support/Host.cpp

Modified: llvm/trunk/lib/Support/Host.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Host.cpp?rev=325439&r1=325438&r2=325439&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Host.cpp (original)
+++ llvm/trunk/lib/Support/Host.cpp Sat Feb 17 08:52:49 2018
@@ -1206,6 +1206,7 @@ bool sys::getHostCPUFeatures(StringMap<b
 
   bool HasExtLeaf1 = MaxExtLevel >= 0x80000001 &&
                      !getX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
+  Features["sahf"]   = HasExtLeaf1 && ((ECX >>  0) & 1);
   Features["lzcnt"]  = HasExtLeaf1 && ((ECX >>  5) & 1);
   Features["sse4a"]  = HasExtLeaf1 && ((ECX >>  6) & 1);
   Features["prfchw"] = HasExtLeaf1 && ((ECX >>  8) & 1);