[flang] Add -f[no-]vectorize flags

Author: DavidTruby

clang/include/clang/Driver/Driver.h

@@ -856,6 +856,9 @@ void applyOverrideOptions(SmallVectorImpl<const char *> &Args,
                           llvm::StringSet<> &SavedStrings,
                           raw_ostream *OS = nullptr);
 
+bool shouldEnableVectorizerAtOLevel(const llvm::opt::ArgList &Args,
+                                    bool isSlpVec);
+
 } // end namespace driver
 } // end namespace clang
 

clang/include/clang/Driver/Options.td

@@ -4038,11 +4038,15 @@ defm assumptions : BoolFOption<"assumptions",
           "Disable codegen and compile-time checks for C++23's [[assume]] attribute">,
   PosFlag<SetTrue>>;
 
+
+let Visibility = [ClangOption, FlangOption] in {
 def fvectorize : Flag<["-"], "fvectorize">, Group<f_Group>,
   HelpText<"Enable the loop vectorization passes">;
 def fno_vectorize : Flag<["-"], "fno-vectorize">, Group<f_Group>;
 def : Flag<["-"], "ftree-vectorize">, Alias<fvectorize>;
 def : Flag<["-"], "fno-tree-vectorize">, Alias<fno_vectorize>;
+}
+
 def fslp_vectorize : Flag<["-"], "fslp-vectorize">, Group<f_Group>,
   HelpText<"Enable the superword-level parallelism vectorization passes">;
 def fno_slp_vectorize : Flag<["-"], "fno-slp-vectorize">, Group<f_Group>;
@@ -7323,6 +7327,10 @@ let Visibility = [CC1Option, FC1Option] in {
 def mlink_builtin_bitcode : Separate<["-"], "mlink-builtin-bitcode">,
   HelpText<"Link and internalize needed symbols from the given bitcode file "
            "before performing optimizations.">;
+
+def vectorize_loops : Flag<["-"], "vectorize-loops">,
+  HelpText<"Run the Loop vectorization passes">,
+  MarshallingInfoFlag<CodeGenOpts<"VectorizeLoop">>;
 } // let Visibility = [CC1Option, FC1Option]
 
 let Visibility = [CC1Option] in {
@@ -7439,9 +7447,6 @@ defm link_builtin_bitcode_postopt: BoolMOption<"link-builtin-bitcode-postopt",
   PosFlag<SetTrue, [], [ClangOption], "Link builtin bitcodes after the "
   "optimization pipeline">,
   NegFlag<SetFalse, [], [ClangOption]>>;
-def vectorize_loops : Flag<["-"], "vectorize-loops">,
-  HelpText<"Run the Loop vectorization passes">,
-  MarshallingInfoFlag<CodeGenOpts<"VectorizeLoop">>;
 def vectorize_slp : Flag<["-"], "vectorize-slp">,
   HelpText<"Run the SLP vectorization passes">,
   MarshallingInfoFlag<CodeGenOpts<"VectorizeSLP">>;

clang/lib/Driver/Driver.cpp

@@ -6980,3 +6980,37 @@ void driver::applyOverrideOptions(SmallVectorImpl<const char *> &Args,
       ++S;
   }
 }
+
+/// Vectorize at all optimization levels greater than 1 except for -Oz.
+/// For -Oz the loop vectorizer is disabled, while the slp vectorizer is
+/// enabled.
+bool driver::shouldEnableVectorizerAtOLevel(const ArgList &Args,
+                                            bool isSlpVec) {
+  if (Arg *A = Args.getLastArg(options::OPT_O_Group)) {
+    if (A->getOption().matches(options::OPT_O4) ||
+        A->getOption().matches(options::OPT_Ofast))
+      return true;
+
+    if (A->getOption().matches(options::OPT_O0))
+      return false;
+
+    assert(A->getOption().matches(options::OPT_O) && "Must have a -O flag");
+
+    // Vectorize -Os.
+    StringRef S(A->getValue());
+    if (S == "s")
+      return true;
+
+    // Don't vectorize -Oz, unless it's the slp vectorizer.
+    if (S == "z")
+      return isSlpVec;
+
+    unsigned OptLevel = 0;
+    if (S.getAsInteger(10, OptLevel))
+      return false;
+
+    return OptLevel > 1;
+  }
+
+  return false;
+}

clang/lib/Driver/ToolChains/Clang.cpp

@@ -503,39 +503,6 @@ static void addCoveragePrefixMapArg(const Driver &D, const ArgList &Args,
   }
 }
 
-/// Vectorize at all optimization levels greater than 1 except for -Oz.
-/// For -Oz the loop vectorizer is disabled, while the slp vectorizer is
-/// enabled.
-static bool shouldEnableVectorizerAtOLevel(const ArgList &Args, bool isSlpVec) {
-  if (Arg *A = Args.getLastArg(options::OPT_O_Group)) {
-    if (A->getOption().matches(options::OPT_O4) ||
-        A->getOption().matches(options::OPT_Ofast))
-      return true;
-
-    if (A->getOption().matches(options::OPT_O0))
-      return false;
-
-    assert(A->getOption().matches(options::OPT_O) && "Must have a -O flag");
-
-    // Vectorize -Os.
-    StringRef S(A->getValue());
-    if (S == "s")
-      return true;
-
-    // Don't vectorize -Oz, unless it's the slp vectorizer.
-    if (S == "z")
-      return isSlpVec;
-
-    unsigned OptLevel = 0;
-    if (S.getAsInteger(10, OptLevel))
-      return false;
-
-    return OptLevel > 1;
-  }
-
-  return false;
-}
-
 /// Add -x lang to \p CmdArgs for \p Input.
 static void addDashXForInput(const ArgList &Args, const InputInfo &Input,
                              ArgStringList &CmdArgs) {

clang/lib/Driver/ToolChains/Flang.cpp

@@ -143,6 +143,16 @@ void Flang::addCodegenOptions(const ArgList &Args,
       !stackArrays->getOption().matches(options::OPT_fno_stack_arrays))
     CmdArgs.push_back("-fstack-arrays");
 
+  // Enable vectorization per default according to the optimization level
+  // selected. For optimization levels that want vectorization we use the alias
+  // option to simplify the hasFlag logic.
+  bool enableVec = shouldEnableVectorizerAtOLevel(Args, false);
+  OptSpecifier vectorizeAliasOption =
+      enableVec ? options::OPT_O_Group : options::OPT_fvectorize;
+  if (Args.hasFlag(options::OPT_fvectorize, vectorizeAliasOption,
+                   options::OPT_fno_vectorize, enableVec))
+    CmdArgs.push_back("-vectorize-loops");
+
   if (shouldLoopVersion(Args))
     CmdArgs.push_back("-fversion-loops-for-stride");
 

flang/include/flang/Frontend/CodeGenOptions.def

@@ -31,6 +31,7 @@ CODEGENOPT(PrepareForFullLTO , 1, 0) ///< Set when -flto is enabled on the
 CODEGENOPT(PrepareForThinLTO , 1, 0) ///< Set when -flto=thin is enabled on the
                                      ///< compile step.
 CODEGENOPT(StackArrays, 1, 0) ///< -fstack-arrays (enable the stack-arrays pass)
+CODEGENOPT(VectorizeLoop, 1, 0) ///< Enable loop vectorization.
 CODEGENOPT(LoopVersioning, 1, 0) ///< Enable loop versioning.
 CODEGENOPT(AliasAnalysis, 1, 0) ///< Enable alias analysis pass
 

flang/lib/Frontend/CompilerInvocation.cpp

@@ -23,6 +23,7 @@
 #include "clang/Basic/AllDiagnostics.h"
 #include "clang/Basic/DiagnosticDriver.h"
 #include "clang/Basic/DiagnosticOptions.h"
+#include "clang/Driver/Driver.h"
 #include "clang/Driver/DriverDiagnostic.h"
 #include "clang/Driver/OptionUtils.h"
 #include "clang/Driver/Options.h"
@@ -242,6 +243,9 @@ static void parseCodeGenArgs(Fortran::frontend::CodeGenOptions &opts,
                    clang::driver::options::OPT_fno_stack_arrays, false))
     opts.StackArrays = 1;
 
+  if (args.getLastArg(clang::driver::options::OPT_vectorize_loops))
+    opts.VectorizeLoop = 1;
+
   if (args.hasFlag(clang::driver::options::OPT_floop_versioning,
                    clang::driver::options::OPT_fno_loop_versioning, false))
     opts.LoopVersioning = 1;

flang/lib/Frontend/FrontendActions.cpp

@@ -982,6 +982,9 @@ void CodeGenAction::runOptimizationPipeline(llvm::raw_pwrite_stream &os) {
   llvm::StandardInstrumentations si(llvmModule->getContext(),
                                     opts.DebugPassManager);
   si.registerCallbacks(pic, &mam);
+
+  pto.LoopVectorization = opts.VectorizeLoop;
+
   llvm::PassBuilder pb(targetMachine, pto, pgoOpt, &pic);
 
   // Attempt to load pass plugins and register their callbacks with PB.

flang/test/Driver/optimization-remark.f90

@@ -5,33 +5,33 @@
 ! DEFINE: %{output} = -emit-llvm -flang-deprecated-no-hlfir -o /dev/null 2>&1
 
 ! Check fc1 can handle -Rpass
-! RUN: %flang_fc1 %s -O1 -Rpass %{output} 2>&1 | FileCheck %s --check-prefix=REMARKS
+! RUN: %flang_fc1 %s -O1 -vectorize-loops -Rpass %{output} 2>&1 | FileCheck %s --check-prefix=REMARKS
 
 ! Check that we can override -Rpass= with -Rno-pass.
-! RUN: %flang_fc1 %s -O1 -Rpass -Rno-pass %{output} 2>&1 | FileCheck %s --allow-empty --check-prefix=NO-REMARKS
+! RUN: %flang_fc1 %s -O1 -vectorize-loops -Rpass -Rno-pass %{output} 2>&1 | FileCheck %s --allow-empty --check-prefix=NO-REMARKS
 
 ! Check -Rno-pass, -Rno-pass-analysis, -Rno-pass-missed nothing emitted
-! RUN: %flang %s -O1 -Rno-pass -S %{output} 2>&1 | FileCheck %s --allow-empty --check-prefix=NO-REMARKS
-! RUN: %flang %s -O1 -Rno-pass-missed -S %{output} 2>&1 | FileCheck %s --allow-empty --check-prefix=NO-REMARKS
-! RUN: %flang %s -O1 -Rno-pass-analysis -S %{output} 2>&1 | FileCheck %s --allow-empty --check-prefix=NO-REMARKS
+! RUN: %flang %s -O2 -Rno-pass -S %{output} 2>&1 | FileCheck %s --allow-empty --check-prefix=NO-REMARKS
+! RUN: %flang %s -O2 -Rno-pass-missed -S %{output} 2>&1 | FileCheck %s --allow-empty --check-prefix=NO-REMARKS
+! RUN: %flang %s -O2 -Rno-pass-analysis -S %{output} 2>&1 | FileCheck %s --allow-empty --check-prefix=NO-REMARKS
 
 ! Check valid -Rpass regex
-! RUN: %flang %s -O1 -Rpass=loop -S %{output} 2>&1 | FileCheck %s --check-prefix=PASS-REGEX-LOOP-ONLY
+! RUN: %flang %s -O2 -Rpass=loop -S %{output} 2>&1 | FileCheck %s --check-prefix=PASS-REGEX-LOOP-ONLY
 
 ! Check valid -Rpass-missed regex
-! RUN: %flang %s -O1 -Rpass-missed=loop -S %{output} 2>&1 | FileCheck %s --check-prefix=MISSED-REGEX-LOOP-ONLY
+! RUN: %flang %s -O2 -Rpass-missed=loop -S %{output} 2>&1 | FileCheck %s --check-prefix=MISSED-REGEX-LOOP-ONLY
 
 ! Check valid -Rpass-analysis regex
-! RUN: %flang %s -O1 -Rpass-analysis=loop -S %{output} 2>&1 | FileCheck %s --check-prefix=ANALYSIS-REGEX-LOOP-ONLY
+! RUN: %flang %s -O2 -Rpass-analysis=loop -S %{output} 2>&1 | FileCheck %s --check-prefix=ANALYSIS-REGEX-LOOP-ONLY
 
 ! Check full -Rpass message is emitted
-! RUN: %flang %s -O1 -Rpass -S %{output} 2>&1 | FileCheck %s --check-prefix=PASS
+! RUN: %flang %s -O2 -Rpass -S %{output} 2>&1 | FileCheck %s --check-prefix=PASS
 
 ! Check full -Rpass-missed message is emitted
-! RUN: %flang %s -O1 -Rpass-missed -S %{output} 2>&1 | FileCheck %s --check-prefix=MISSED
+! RUN: %flang %s -O2 -Rpass-missed -S %{output} 2>&1 | FileCheck %s --check-prefix=MISSED
 
 ! Check full -Rpass-analysis message is emitted
-! RUN: %flang %s -O1 -Rpass-analysis -S -o /dev/null 2>&1 | FileCheck %s --check-prefix=ANALYSIS
+! RUN: %flang %s -O2 -Rpass-analysis -S -o /dev/null 2>&1 | FileCheck %s --check-prefix=ANALYSIS
 
 ! REMARKS: remark:
 ! NO-REMARKS-NOT: remark: