[OPENMP] -fopenmp enables OpenMP support (fix for http://llvm.org/PR23492)

[ABataev]

Summary

-fopenmp turns on OpenMP support and links libiomp5 as OpenMP library. Also there is -fopenmp={libiomp5|libgomp} option that allows to override effect of -fopenmp and link libgomp library (if -fopenmp=libgomp is specified).

[ABataev]

Ping!

[rsmith]

lib/Driver/Tools.cpp

3812–3813

Is there a reason to forward both of these to the frontend? It seems more inline with the design goal of giving the frontend a minimal and explicit interface to either rewrite -fopenmp to -fopenmp=libiomp5 in the driver or to not expose the underlying library to the frontend at all (it doesn't seem like the frontend needs to care).

[ABataev]

Replace frontend option -fopenmp=libiomp5 by -fopenmp per comment from Richard Smith

[rsmith]

LGTM

lib/Driver/Tools.cpp

   Args.AddLastArg(CmdArgs, options::OPT_fno_operator_names);
   // AltiVec language extensions aren't relevant for assembling.
   if (!isa<PreprocessJobAction>(JA) || 
       Output.getType() != types::TY_PP_Asm)
     Args.AddLastArg(CmdArgs, options::OPT_faltivec);
   Args.AddLastArg(CmdArgs, options::OPT_fdiagnostics_show_template_tree);
   Args.AddLastArg(CmdArgs, options::OPT_fno_elide_type);
 
+  // Forward flags for OpenMP
+  Args.AddLastArg(CmdArgs, options::OPT_fopenmp);
+  Args.AddLastArg(CmdArgs, options::OPT_fopenmp_EQ);
+
   const SanitizerArgs &Sanitize = getToolChain().getSanitizerArgs();
   Sanitize.addArgs(Args, CmdArgs);
 
   // Report an error for -faltivec on anything other than PowerPC.
   if (const Arg *A = Args.getLastArg(options::OPT_faltivec))
     if (!(getToolChain().getArch() == llvm::Triple::ppc ||
           getToolChain().getArch() == llvm::Triple::ppc64 ||
           getToolChain().getArch() == llvm::Triple::ppc64le))
void darwin::Link::ConstructJob(Compilation &C, const JobAction &JA,
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nostartfiles))
     getMachOToolChain().addStartObjectFileArgs(Args, CmdArgs);
 
   Args.AddAllArgs(CmdArgs, options::OPT_L);
 
   LibOpenMP UsedOpenMPLib = LibUnknown;
-  if (Args.hasArg(options::OPT_fopenmp)) {
-    UsedOpenMPLib = LibGOMP;
-  } else if (const Arg *A = Args.getLastArg(options::OPT_fopenmp_EQ)) {
+  if (const Arg *A = Args.getLastArg(options::OPT_fopenmp_EQ)) {
     UsedOpenMPLib = llvm::StringSwitch<LibOpenMP>(A->getValue())
         .Case("libgomp",  LibGOMP)
         .Case("libiomp5", LibIOMP5)
         .Default(LibUnknown);
     if (UsedOpenMPLib == LibUnknown)
       getToolChain().getDriver().Diag(diag::err_drv_unsupported_option_argument)
         << A->getOption().getName() << A->getValue();
+  } else if (Args.hasArg(options::OPT_fopenmp)) {
+    UsedOpenMPLib = LibIOMP5;
   }
   switch (UsedOpenMPLib) {
   case LibGOMP:
     CmdArgs.push_back("-lgomp");
     break;
   case LibIOMP5:
     CmdArgs.push_back("-liomp5");
     break;
if (!Args.hasArg(options::OPT_nostdlib)) {
     if (!Args.hasArg(options::OPT_nodefaultlibs)) {
       if (Args.hasArg(options::OPT_static))
         CmdArgs.push_back("--start-group");
 
       if (NeedsSanitizerDeps)
         linkSanitizerRuntimeDeps(ToolChain, CmdArgs);
 
       LibOpenMP UsedOpenMPLib = LibUnknown;
-      if (Args.hasArg(options::OPT_fopenmp)) {
-        UsedOpenMPLib = LibGOMP;
-      } else if (const Arg *A = Args.getLastArg(options::OPT_fopenmp_EQ)) {
+      if (const Arg *A = Args.getLastArg(options::OPT_fopenmp_EQ)) {
         UsedOpenMPLib = llvm::StringSwitch<LibOpenMP>(A->getValue())
-            .Case("libgomp",  LibGOMP)
+                            .Case("libgomp", LibGOMP)
                             .Case("libiomp5", LibIOMP5)
                             .Default(LibUnknown);
         if (UsedOpenMPLib == LibUnknown)
           D.Diag(diag::err_drv_unsupported_option_argument)
               << A->getOption().getName() << A->getValue();
+      } else if (Args.hasArg(options::OPT_fopenmp)) {
+        UsedOpenMPLib = LibIOMP5;
       }
       switch (UsedOpenMPLib) {
       case LibGOMP:
         CmdArgs.push_back("-lgomp");
 
         // FIXME: Exclude this for platforms with libgomp that don't require
         // librt. Most modern Linux platforms require it, but some may not.
         CmdArgs.push_back("-lrt");

lib/Frontend/CompilerInvocation.cpp

LangOptions::PragmaMSPointersToMembersKind InheritanceModel =
             .Default(LangOptions::PPTMK_BestCase);
     if (InheritanceModel == LangOptions::PPTMK_BestCase)
       Diags.Report(diag::err_drv_invalid_value)
           << "-fms-memptr-rep=" << A->getValue();
 
     Opts.setMSPointerToMemberRepresentationMethod(InheritanceModel);
   }
 
-  // Check if -fopenmp= is specified.
+  // Check if -fopenmp or -fopenmp= is specified.
+  Opts.OpenMP = Args.hasArg(options::OPT_fopenmp);
   if (const Arg *A = Args.getLastArg(options::OPT_fopenmp_EQ)) {
     Opts.OpenMP = llvm::StringSwitch<bool>(A->getValue())
                       .Case("libiomp5", true)
                       .Default(false);
   }
 
   // Record whether the __DEPRECATED define was requested.
   Opts.Deprecated = Args.hasFlag(OPT_fdeprecated_macro,
                                  OPT_fno_deprecated_macro,
                                  Opts.Deprecated);
 
   // FIXME: Eliminate this dependency.

test/OpenMP/linking.c

 // Test the that the driver produces reasonable linker invocations with
 // -fopenmp or -fopenmp=libiomp5|libgomp.
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -fopenmp -target i386-unknown-linux \
 // RUN:   | FileCheck --check-prefix=CHECK-LD-32 %s
 // CHECK-LD-32: "{{.*}}ld{{(.exe)?}}"
-// CHECK-LD-32: "-lgomp" "-lrt" "-lgcc"
+// CHECK-LD-32: "-liomp5" "-lgcc"
 // CHECK-LD-32: "-lpthread" "-lc"
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -fopenmp -target x86_64-unknown-linux \
 // RUN:   | FileCheck --check-prefix=CHECK-LD-64 %s
 // CHECK-LD-64: "{{.*}}ld{{(.exe)?}}"
-// CHECK-LD-64: "-lgomp" "-lrt" "-lgcc"
+// CHECK-LD-64: "-liomp5" "-lgcc"
 // CHECK-LD-64: "-lpthread" "-lc"
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -fopenmp=libgomp -target i386-unknown-linux \
 // RUN:   | FileCheck --check-prefix=CHECK-GOMP-LD-32 %s
 // CHECK-GOMP-LD-32: "{{.*}}ld{{(.exe)?}}"
 // CHECK-GOMP-LD-32: "-lgomp" "-lrt" "-lgcc"
 // CHECK-GOMP-LD-32: "-lpthread" "-lc"

 // CHECK-LIB-LD-32: error: unsupported argument 'lib' to option 'fopenmp='
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -fopenmp=lib -target x86_64-unknown-linux \
 // RUN:   | FileCheck --check-prefix=CHECK-LIB-LD-64 %s
 // CHECK-LIB-LD-64: error: unsupported argument 'lib' to option 'fopenmp='
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
-// RUN:     -fopenmp -fopenmp=libiomp5 -target i386-unknown-linux \
-// RUN:   | FileCheck --check-prefix=CHECK-LD-WARN-32 %s
-// CHECK-LD-WARN-32: warning: argument unused during compilation: '-fopenmp=libiomp5'
-// CHECK-LD-WARN-32: "{{.*}}ld{{(.exe)?}}"
-// CHECK-LD-WARN-32: "-lgomp" "-lrt" "-lgcc"
-// CHECK-LD-WARN-32: "-lpthread" "-lc"
+// RUN:     -fopenmp -fopenmp=libgomp -target i386-unknown-linux \
+// RUN:   | FileCheck --check-prefix=CHECK-LD-OVERRIDE-32 %s
+// CHECK-LD-OVERRIDE-32: "{{.*}}ld{{(.exe)?}}"
+// CHECK-LD-OVERRIDE-32: "-lgomp" "-lrt" "-lgcc"
+// CHECK-LD-OVERRIDE-32: "-lpthread" "-lc"
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
-// RUN:     -fopenmp -fopenmp=libiomp5 -target x86_64-unknown-linux \
-// RUN:   | FileCheck --check-prefix=CHECK-LD-WARN-64 %s
-// CHECK-LD-WARN-64: warning: argument unused during compilation: '-fopenmp=libiomp5'
-// CHECK-LD-WARN-64: "{{.*}}ld{{(.exe)?}}"
-// CHECK-LD-WARN-64: "-lgomp" "-lrt" "-lgcc"
-// CHECK-LD-WARN-64: "-lpthread" "-lc"
+// RUN:     -fopenmp -fopenmp=libgomp -target x86_64-unknown-linux \
+// RUN:   | FileCheck --check-prefix=CHECK-LD-OVERRIDE-64 %s
+// CHECK-LD-OVERRIDE-64: "{{.*}}ld{{(.exe)?}}"
+// CHECK-LD-OVERRIDE-64: "-lgomp" "-lrt" "-lgcc"
+// CHECK-LD-OVERRIDE-64: "-lpthread" "-lc"
 //

test/OpenMP/openmp_common.c

 // RUN: %clang_cc1 -verify -fopenmp=libiomp5 -ferror-limit 100 -o - %s
+// RUN: %clang_cc1 -verify -fopenmp -ferror-limit 100 -o - %s
 
 #pragma omp // expected-error {{expected an OpenMP directive}}
 #pragma omp unknown_directive // expected-error {{expected an OpenMP directive}}
 
 void foo() {
 #pragma omp // expected-error {{expected an OpenMP directive}}
 #pragma omp unknown_directive // expected-error {{expected an OpenMP directive}}
 }

test/OpenMP/predefined_macro.c

 // RUN: %clang_cc1 -fopenmp=libiomp5 -verify -DFOPENMP -o - %s
+// RUN: %clang_cc1 -fopenmp -verify -DFOPENMP -o - %s
 // RUN: %clang_cc1 -verify -o - %s
+// RUN: %clang_cc1 -verify -fopenmp -fopenmp=libgomp -o - %s
 // expected-no-diagnostics
 #ifdef FOPENMP
-// -fopenmp=libiomp5 option is specified
+// -fopenmp=libiomp5 or -fopenmp option is specified
 #ifndef _OPENMP
 #error "No _OPENMP macro is defined with -fopenmp option"
 #elsif _OPENMP != 201307
 #error "_OPENMP has incorrect value"
 #endif //_OPENMP
 #else
-// No -fopenmp=libiomp5 option is specified
+// No -fopenmp=libiomp5 or -fopenmp option is specified
 #ifdef _OPENMP
 #error "_OPENMP macro is defined without -fopenmp option"
 #endif // _OPENMP
 #endif // FOPENMP
 
-// RUN: %clang_cc1 -fopenmp=libiomp5 -verify -DFOPENMP -o - %s
-// RUN: %clang_cc1 -verify -o - %s
-// expected-no-diagnostics
-#ifdef FOPENMP
-// -fopenmp=libiomp5 option is specified
-#ifndef _OPENMP
-#error "No _OPENMP macro is defined with -fopenmp option"
-#elsif _OPENMP != 201307
-#error "_OPENMP has incorrect value"
-#endif // _OPENMP
-#else
-// No -fopenmp=libiomp5 option is specified
-#ifdef _OPENMP
-#error "_OPENMP macro is defined without -fopenmp option"
-#endif // _OPENMP
-#endif // FOPENMP