Add --print-supported-cpus flag for clang.

This patch allows clang users to print out a list of supported CPU models using
clang [--target=<target triple>] --print-supported-cpus

Then, users can select the CPU model to compile to using
clang --target=<triple> -mcpu=<model> a.c

It is a handy feature to help cross compilation.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@363464 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/ClangCommandLineReference.rst b/docs/ClangCommandLineReference.rst
index 30ac27f95f9ddce3c3741f66da0709c9cb1ed6d8..bad91ff830d21f14ba04cc1db8e87333b7de6b6e 100644 (file)
--- a/docs/ClangCommandLineReference.rst
+++ b/docs/ClangCommandLineReference.rst
@@ -610,6 +610,10 @@ C++ standard library to use
 
 Generate code for the given target
 
+.. option:: --print-supported-cpus
+
+Print supported cpu models for the given target
+
 .. option:: -time
 
 Time individual commands

diff --git a/docs/CommandGuide/clang.rst b/docs/CommandGuide/clang.rst
index 84e0dddb8e1fc5628eb44f7e7bd81e4703a7bd97..1ed11c77ad0676e3650391cb0dc8f390d4b2c09d 100644 (file)
--- a/docs/CommandGuide/clang.rst
+++ b/docs/CommandGuide/clang.rst
@@ -324,6 +324,12 @@ number of cross compilers, or may only support a native target.
   When building for iPhone OS, specify the minimum version supported by your
   application.
 
+.. option:: --print-supported-cpus
+
+  Print out a list of supported processors for the given target (specified 
+  through --target=<architecture> or -arch <architecture>). If no target is 
+  specified, the system default target will be used.
+
 .. option:: -march=<cpu>
 
   Specify that Clang should generate code for a specific processor family

diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index 65c1721daa8b8d78aa33e79c316aaad9b75257e1..07d1c220c795c94c9eab1bc51fd3e1d89c918b5e 100644 (file)
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -2632,6 +2632,10 @@ def : Separate<["--"], "no-system-header-prefix">, Alias<no_system_header_prefix
 def s : Flag<["-"], "s">, Group<Link_Group>;
 def target : Joined<["--"], "target=">, Flags<[DriverOption, CoreOption]>,
   HelpText<"Generate code for the given target">;
+def _print_supported_cpus : Flag<["-", "--"], "print-supported-cpus">,
+  Group<CompileOnly_Group>, Flags<[CC1Option, CoreOption]>,
+  HelpText<"Print supported cpu models for the given target (if target is not specified,"
+           " it will print the supported cpus for the default target)">;
 def gcc_toolchain : Joined<["--"], "gcc-toolchain=">, Flags<[DriverOption]>,
   HelpText<"Use the gcc toolchain at the given directory">;
 def time : Flag<["-"], "time">,

diff --git a/include/clang/Frontend/FrontendOptions.h b/include/clang/Frontend/FrontendOptions.h
index 1bbd048967489564c4849bb579e660e3fba3713e..66fbe6ae6ca7ab78624581b739036678e21c2698 100644 (file)
--- a/include/clang/Frontend/FrontendOptions.h
+++ b/include/clang/Frontend/FrontendOptions.h
@@ -260,6 +260,9 @@ public:
   /// Show timers for individual actions.
   unsigned ShowTimers : 1;
 
+  /// print the supported cpus for the current target
+  unsigned PrintSupportedCPUs : 1;
+
   /// Output time trace profile.
   unsigned TimeTrace : 1;
 

diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index 17552b28763a9fc60cec5be841ba19db9eeb862c..3bda71597e3a0cb39cbe6c093a0a32ed99ae11ca 100644 (file)
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -1671,7 +1671,8 @@ bool Driver::HandleImmediateArgs(const Compilation &C) {
   }
 
   if (C.getArgs().hasArg(options::OPT_v) ||
-      C.getArgs().hasArg(options::OPT__HASH_HASH_HASH)) {
+      C.getArgs().hasArg(options::OPT__HASH_HASH_HASH) ||
+      C.getArgs().hasArg(options::OPT__print_supported_cpus)) {
     PrintVersion(C, llvm::errs());
     SuppressMissingInputWarning = true;
   }
@@ -3375,6 +3376,17 @@ void Driver::BuildActions(Compilation &C, DerivedArgList &Args,
     Args.ClaimAllArgs(options::OPT_cl_compile_Group);
   }
 
+  // If the use specify --print-supported-cpus, clang will only print out
+  // supported cpu names without doing compilation.
+  if (Arg *A = Args.getLastArg(options::OPT__print_supported_cpus)) {
+    Actions.clear();
+    // the compilation now has only two phases: Input and Compile
+    // use the --prints-supported-cpus flag as the dummy input to cc1
+    Action *InputAc = C.MakeAction<InputAction>(*A, types::TY_C);
+    Actions.push_back(
+        C.MakeAction<PrecompileJobAction>(InputAc, types::TY_Nothing));
+  }
+
   // Claim ignored clang-cl options.
   Args.ClaimAllArgs(options::OPT_cl_ignored_Group);
 

diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 5596e4b6a3c8c1a87c1cd3d02e012d2791c6f372..7ba08c6acad050c09fcbed0ab64911e788173e03 100644 (file)
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -1752,6 +1752,7 @@ static InputKind ParseFrontendArgs(FrontendOptions &Opts, ArgList &Args,
   Opts.ShowHelp = Args.hasArg(OPT_help);
   Opts.ShowStats = Args.hasArg(OPT_print_stats);
   Opts.ShowTimers = Args.hasArg(OPT_ftime_report);
+  Opts.PrintSupportedCPUs = Args.hasArg(OPT__print_supported_cpus);
   Opts.TimeTrace = Args.hasArg(OPT_ftime_trace);
   Opts.ShowVersion = Args.hasArg(OPT_version);
   Opts.ASTMergeFiles = Args.getAllArgValues(OPT_ast_merge);

diff --git a/test/Driver/print-supported-cpus.c b/test/Driver/print-supported-cpus.c
new file mode 100644 (file)
index 0000000..a6b9a71
--- /dev/null
+++ b/test/Driver/print-supported-cpus.c
@@ -0,0 +1,16 @@
+// Test that the --print-supported-cpus flag works
+
+// RUN: %clang --target=x86_64-unknown-linux-gnu \
+// RUN:   --print-supported-cpus 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=CHECK-X86
+// CHECK-X86: Target: x86_64-unknown-linux-gnu
+// CHECK-X86: corei7
+// CHECK-X86: Use -mcpu or -mtune to specify the target's processor.
+
+// RUN: %clang --target=arm-unknown-linux-android \
+// RUN:   --print-supported-cpus 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=CHECK-ARM
+// CHECK-ARM: Target: arm-unknown-linux-android
+// CHECK-ARM: cortex-a73
+// CHECK-ARM: cortex-a75
+// CHECK-ARM: Use -mcpu or -mtune to specify the target's processor.

diff --git a/tools/driver/cc1_main.cpp b/tools/driver/cc1_main.cpp
index 2ed27c22708aa039467ac54f9096c86f1589323e..01a42489333397f213946edfefab1486a58ab67e 100644 (file)
--- a/tools/driver/cc1_main.cpp
+++ b/tools/driver/cc1_main.cpp
@@ -13,6 +13,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Basic/Stack.h"
+#include "clang/Basic/TargetOptions.h"
 #include "clang/CodeGen/ObjectFilePCHContainerOperations.h"
 #include "clang/Config/config.h"
 #include "clang/Driver/DriverDiagnostic.h"
@@ -36,10 +37,12 @@
 #include "llvm/Support/ManagedStatic.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Signals.h"
+#include "llvm/Support/TargetRegistry.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Support/TimeProfiler.h"
 #include "llvm/Support/Timer.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetMachine.h"
 #include <cstdio>
 
 #ifdef CLANG_HAVE_RLIMITS
@@ -166,6 +169,23 @@ static void ensureSufficientStack() {
 static void ensureSufficientStack() {}
 #endif
 
+/// print supported cpus of the given target
+int PrintSupportedCPUs(std::string TargetStr) {
+  std::string Error;
+  const llvm::Target *TheTarget =
+      llvm::TargetRegistry::lookupTarget(TargetStr, Error);
+  if (!TheTarget) {
+    llvm::errs() << Error;
+    return 1;
+  }
+
+  // the target machine will handle the mcpu printing
+  llvm::TargetOptions Options;
+  std::unique_ptr<llvm::TargetMachine> TheTargetMachine(
+      TheTarget->createTargetMachine(TargetStr, "", "+cpuHelp", Options, None));
+  return 0;
+}
+
 int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
   ensureSufficientStack();
 
@@ -199,6 +219,11 @@ int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
   if (Clang->getFrontendOpts().TimeTrace)
     llvm::timeTraceProfilerInitialize();
 
+  // --print-supported-cpus takes priority over the actual compilation
+  if (Clang->getFrontendOpts().PrintSupportedCPUs) {
+    return PrintSupportedCPUs(Clang->getTargetOpts().Triple);
+  }
+
   // Infer the builtin include path if unspecified.
   if (Clang->getHeaderSearchOpts().UseBuiltinIncludes &&
       Clang->getHeaderSearchOpts().ResourceDir.empty())