opt: Mirror vectorization presets of clang

clang enables vectorization at optimization levels > 1 and size level < 2. opt
should behave similarily.

Loop vectorization and SLP vectorization can be disabled with the flags
-disable-(loop/slp)-vectorization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196294 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 2 deletions

diff --git a/tools/opt/opt.cpp b/tools/opt/opt.cpp
index 8a8da01a99..dba16f72da 100644
--- a/tools/opt/opt.cpp
+++ b/tools/opt/opt.cpp
@@ -139,6 +139,16 @@ static cl::opt<bool>
 DisableLoopUnrolling("disable-loop-unrolling",
                      cl::desc("Disable loop unrolling in all relevant passes"),
                      cl::init(false));
+static cl::opt<bool>
+DisableLoopVectorization("disable-loop-vectorization",
+                     cl::desc("Disable the loop vectorization pass"),
+                     cl::init(false));
+
+static cl::opt<bool>
+DisableSLPVectorization("disable-slp-vectorization",
+                        cl::desc("Disable the slp vectorization pass"),
+                        cl::init(false));
+
 
 static cl::opt<bool>
 DisableSimplifyLibCalls("disable-simplify-libcalls",
@@ -461,8 +471,10 @@ static void AddOptimizationPasses(PassManagerBase &MPM,FunctionPassManager &FPM,
   Builder.DisableUnrollLoops = (DisableLoopUnrolling.getNumOccurrences() > 0) ?
                                DisableLoopUnrolling : OptLevel == 0;
 
-  Builder.LoopVectorize = OptLevel > 1 && SizeLevel < 2;
-  Builder.SLPVectorize = true;
+  Builder.LoopVectorize =
+      DisableLoopVectorization ? false : OptLevel > 1 && SizeLevel < 2;
+  Builder.SLPVectorize =
+      DisableSLPVectorization ? false : OptLevel > 1 && SizeLevel < 2;
 
   Builder.populateFunctionPassManager(FPM);
   Builder.populateModulePassManager(MPM);