If -fslp-vectorize or -fno-slp-vectorize are given, honor this selection. If no flag is given, enable it for -O3.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@187630 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 3a23732..b6f6c3d 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -1974,6 +1974,12 @@
return false;
}
+static bool isOptimizationLevel3(const ArgList &Args) {
+ if (Arg *A = Args.getLastArg(options::OPT_O_Group))
+ return StringRef(A->getValue()).equals("3");
+ return false;
+}
+
void Clang::ConstructJob(Compilation &C, const JobAction &JA,
const InputInfo &Output,
const InputInfoList &Inputs,
@@ -3452,9 +3458,17 @@
options::OPT_fno_vectorize, true))
CmdArgs.push_back("-vectorize-loops");
- // -fslp-vectorize is default.
- if (Args.hasFlag(options::OPT_fslp_vectorize,
- options::OPT_fno_slp_vectorize, true))
+ bool EnableSLP = false;
+ // If -fslp-vectorize or -fno-slp-vectorize are given, honor this selection.
+ if (Arg *A = Args.getLastArg(options::OPT_fslp_vectorize,
+ options::OPT_fno_slp_vectorize)) {
+ EnableSLP = A->getOption().matches(options::OPT_fslp_vectorize);
+ } else {
+ // Also enable SLP vectorization on O3 or OFast
+ EnableSLP = isOptimizationLevel3(Args) || isOptimizationLevelFast(Args);
+ }
+
+ if (EnableSLP)
CmdArgs.push_back("-vectorize-slp");
// -fno-slp-vectorize-aggressive is default.
