Merge from 'master' to 'sycl-web' (#10)

  CONFLICT (content): Merge conflict in clang/test/Preprocessor/sycl-macro.cpp
  CONFLICT (content): Merge conflict in clang/test/Driver/sycl.c
  CONFLICT (content): Merge conflict in clang/lib/Frontend/CompilerInvocation.cpp
  CONFLICT (content): Merge conflict in clang/lib/Driver/ToolChains/Clang.cpp
  CONFLICT (content): Merge conflict in clang/include/clang/Basic/LangOptions.def

Author: bader

clang/include/clang/Basic/LangOptions.def

@@ -204,6 +204,7 @@ LANGOPT(OpenCL            , 1, 0, "OpenCL")
 LANGOPT(OpenCLVersion     , 32, 0, "OpenCL C version")
 LANGOPT(OpenCLCPlusPlus   , 1, 0, "C++ for OpenCL")
 LANGOPT(OpenCLCPlusPlusVersion     , 32, 0, "C++ for OpenCL version")
+ENUM_LANGOPT(SYCLVersion, SYCLVersionList, 4, SYCLVersionList::undefined, "Version of the SYCL standard used")
 LANGOPT(NativeHalfType    , 1, 0, "Native half type support")
 LANGOPT(NativeHalfArgsAndReturns, 1, 0, "Native half args and returns")
 LANGOPT(HalfArgsAndReturns, 1, 0, "half args and returns")
@@ -230,13 +231,11 @@ LANGOPT(GPURelocatableDeviceCode, 1, 0, "generate relocatable device code")
 LANGOPT(GPUAllowDeviceInit, 1, 0, "allowing device side global init functions for HIP")
 LANGOPT(GPUMaxThreadsPerBlock, 32, 256, "default max threads per block for kernel launch bounds for HIP")
 
-LANGOPT(SYCL              , 1, 0, "SYCL")
 LANGOPT(SYCLIsDevice      , 1, 0, "Generate code for SYCL device")
 LANGOPT(SYCLIsHost        , 1, 0, "SYCL host compilation")
 LANGOPT(SYCLAllowFuncPtr  , 1, 0, "Allow function pointers in SYCL device code")
 LANGOPT(SYCLStdLayoutKernelParams, 1, 0, "Enable standard layout requirement for SYCL kernel parameters")
 LANGOPT(SYCLUnnamedLambda , 1, 0, "Allow unnamed lambda SYCL kernels")
-LANGOPT(SYCLVersion       , 32, 0, "Version of the SYCL standard used")
 
 LANGOPT(HIPUseNewLaunchAPI, 1, 0, "Use new kernel launching API for HIP")
 

clang/include/clang/Driver/Options.td

@@ -545,6 +545,8 @@ def cl_no_signed_zeros : Flag<["-"], "cl-no-signed-zeros">, Group<opencl_Group>,
   HelpText<"OpenCL only. Allow use of less precise no signed zeros computations in the generated binary.">;
 def cl_std_EQ : Joined<["-"], "cl-std=">, Group<opencl_Group>, Flags<[CC1Option]>,
   HelpText<"OpenCL language standard to compile for.">, Values<"cl,CL,cl1.1,CL1.1,cl1.2,CL1.2,cl2.0,CL2.0,clc++,CLC++">;
+def sycl_std_EQ : Joined<["-"], "sycl-std=">, Group<sycl_Group>, Flags<[CC1Option]>,
+  HelpText<"SYCL language standard to compile for.">, Values<"1.2.1">;
 def cl_denorms_are_zero : Flag<["-"], "cl-denorms-are-zero">, Group<opencl_Group>,
   HelpText<"OpenCL only. Allow denormals to be flushed to zero.">;
 def cl_fp32_correctly_rounded_divide_sqrt : Flag<["-"], "cl-fp32-correctly-rounded-divide-sqrt">, Group<opencl_Group>, Flags<[CC1Option]>,
@@ -3477,13 +3479,10 @@ defm underscoring : BooleanFFlag<"underscoring">, Group<gfortran_Group>;
 defm whole_file : BooleanFFlag<"whole-file">, Group<gfortran_Group>;
 
 // C++ SYCL options
-def fsycl : Flag<["-"], "fsycl">, Group<sycl_Group>, Flags<[CC1Option, CoreOption]>,
+def fsycl : Flag<["-"], "fsycl">, Group<sycl_Group>, Flags<[CC1Option, NoArgumentUnused, CoreOption]>,
   HelpText<"Enable SYCL kernels compilation for device">;
-def fno_sycl : Flag<["-"], "fno-sycl">, Group<sycl_Group>, Flags<[CoreOption]>,
-  HelpText<"Disable SYCL kernels compilation for device">;
-def sycl_std_EQ : Joined<["-"], "sycl-std=">, Group<sycl_Group>, Flags<[CC1Option, NoArgumentUnused, CoreOption]>,
-  HelpText<"SYCL language standard to compile for.">, Values<"2017, 121, 1.2.1, sycl-1.2.1">;
-
+def fno_sycl : Flag<["-"], "fno-sycl">, Group<sycl_Group>,
+  HelpText<"Disable SYCL kernels compilation for device">, Flags<[NoArgumentUnused, CoreOption]>;
 def reuse_exe_EQ : Joined<["-"], "reuse-exe=">,
   HelpText<"Speed up FPGA aoc compile if the device code in <exe> is unchanged.">,
   MetaVarName<"<exe>">;

clang/lib/AST/Mangle.cpp

@@ -50,7 +50,8 @@ enum CCMangling {
   CCM_Fast,
   CCM_RegCall,
   CCM_Vector,
-  CCM_Std
+  CCM_Std,
+  CCM_WasmMainArgcArgv
 };
 
 static bool isExternC(const NamedDecl *ND) {
@@ -63,6 +64,16 @@ static CCMangling getCallingConvMangling(const ASTContext &Context,
                                          const NamedDecl *ND) {
   const TargetInfo &TI = Context.getTargetInfo();
   const llvm::Triple &Triple = TI.getTriple();
+
+  // On wasm, the argc/argv form of "main" is renamed so that the startup code
+  // can call it with the correct function signature.
+  // On Emscripten, users may be exporting "main" and expecting to call it
+  // themselves, so we can't mangle it.
+  if (Triple.isWasm() && !Triple.isOSEmscripten())
+    if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
+      if (FD->isMain() && FD->hasPrototype() && FD->param_size() == 2)
+        return CCM_WasmMainArgcArgv;
+
   if (!Triple.isOSWindows() || !Triple.isX86())
     return CCM_Other;
 
@@ -143,6 +154,12 @@ void MangleContext::mangleName(const NamedDecl *D, raw_ostream &Out) {
 
   const ASTContext &ASTContext = getASTContext();
   CCMangling CC = getCallingConvMangling(ASTContext, D);
+
+  if (CC == CCM_WasmMainArgcArgv) {
+    Out << "__main_argc_argv";
+    return;
+  }
+
   bool MCXX = shouldMangleCXXName(D);
   const TargetInfo &TI = Context.getTargetInfo();
   if (CC == CCM_Other || (MCXX && TI.getCXXABI() == TargetCXXABI::Microsoft)) {

clang/lib/CodeGen/CodeGenModule.cpp

@@ -464,6 +464,10 @@ void CodeGenModule::Release() {
     CodeGenFunction(*this).EmitCfiCheckStub();
   }
   emitAtAvailableLinkGuard();
+  if (Context.getTargetInfo().getTriple().isWasm() &&
+      !Context.getTargetInfo().getTriple().isOSEmscripten()) {
+    EmitMainVoidAlias();
+  }
   emitLLVMUsed();
   if (SanStats)
     SanStats->finish();
@@ -5807,6 +5811,17 @@ void CodeGenModule::EmitDeferredUnusedCoverageMappings() {
   }
 }
 
+void CodeGenModule::EmitMainVoidAlias() {
+  // In order to transition away from "__original_main" gracefully, emit an
+  // alias for "main" in the no-argument case so that libc can detect when
+  // new-style no-argument main is in used.
+  if (llvm::Function *F = getModule().getFunction("main")) {
+    if (!F->isDeclaration() && F->arg_size() == 0 && !F->isVarArg() &&
+        F->getReturnType()->isIntegerTy(Context.getTargetInfo().getIntWidth()))
+      addUsedGlobal(llvm::GlobalAlias::create("__main_void", F));
+  }
+}
+
 /// Turns the given pointer into a constant.
 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context,
                                           const void *Ptr) {

clang/lib/CodeGen/CodeGenModule.h

@@ -1036,6 +1036,9 @@ class CodeGenModule : public CodeGenTypeCache {
   /// for the uninstrumented functions.
   void EmitDeferredUnusedCoverageMappings();
 
+  /// Emit an alias for "main" if it has no arguments (needed for wasm).
+  void EmitMainVoidAlias();
+
   /// Tell the consumer that this variable has been instantiated.
   void HandleCXXStaticMemberVarInstantiation(VarDecl *VD);
 

clang/lib/Driver/ToolChains/Clang.cpp

@@ -4080,7 +4080,6 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
 
   if (UseSYCLTriple) {
     // We want to compile sycl kernels.
-    CmdArgs.push_back("-fsycl");
     CmdArgs.push_back("-fsycl-is-device");
     // Pass the triple of host when doing SYCL
     auto AuxT = llvm::Triple(llvm::sys::getProcessTriple());
@@ -4120,7 +4119,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back("-fsycl-std-layout-kernel-params");
   } else if (IsSYCL) {
     // Ensure the default version in SYCL mode is 1.2.1
-      CmdArgs.push_back("-sycl-std=2017");
+    CmdArgs.push_back("-sycl-std=1.2.1");
   }
 
   if (IsOpenMPDevice) {

clang/lib/Frontend/CompilerInvocation.cpp

@@ -2538,22 +2538,22 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
       LangStd = OpenCLLangStd;
   }
 
-  Opts.SYCL = Args.hasArg(options::OPT_fsycl);
-  Opts.SYCLIsDevice = Opts.SYCL && Args.hasArg(options::OPT_fsycl_is_device);
-  if (Opts.SYCL) {
-    // -sycl-std applies to any SYCL source, not only those containing kernels,
-    // but also those using the SYCL API
-    if (const Arg *A = Args.getLastArg(OPT_sycl_std_EQ)) {
-      Opts.SYCLVersion = llvm::StringSwitch<unsigned>(A->getValue())
-                             .Cases("2017", "1.2.1", "121", "sycl-1.2.1", 2017)
-                             .Default(0U);
-
-      if (Opts.SYCLVersion == 0U) {
-        // User has passed an invalid value to the flag, this is an error
-        Diags.Report(diag::err_drv_invalid_value)
-            << A->getAsString(Args) << A->getValue();
-      }
+  // -sycl-std applies to any SYCL source, not only those containing kernels,
+  // but also those using the SYCL API
+  if(const Arg  *A = Args.getLastArg(OPT_sycl_std_EQ)) {
+    Opts.setSYCLVersion(llvm::StringSwitch<LangOptions::SYCLVersionList>(A->getValue())
+      .Cases("1.2.1",  "121", "sycl-1.2.1", LangOptions::SYCLVersionList::sycl_1_2_1)
+      .Default(LangOptions::SYCLVersionList::undefined));
+
+    if (Opts.getSYCLVersion() == LangOptions::SYCLVersionList::undefined) {
+      // User has passed an invalid value to the flag, this is an error
+      Diags.Report(diag::err_drv_invalid_value) 
+          << A->getAsString(Args) << A->getValue();
     }
+  } else if (Args.hasArg(options::OPT_fsycl_is_device) 
+                         || Args.hasArg(options::OPT_fsycl_is_host)
+                         || Args.hasArg(options::OPT_fsycl)) {
+    Opts.setSYCLVersion(LangOptions::SYCLVersionList::sycl_1_2_1);
   }
 
   Opts.IncludeDefaultHeader = Args.hasArg(OPT_finclude_default_header);

clang/lib/Frontend/InitHeaderSearch.cpp

@@ -433,8 +433,7 @@ void InitHeaderSearch::AddDefaultIncludePaths(const LangOptions &Lang,
     break;
 
   case llvm::Triple::UnknownOS:
-    if (triple.getArch() == llvm::Triple::wasm32 ||
-        triple.getArch() == llvm::Triple::wasm64)
+    if (triple.isWasm())
       return;
     break;
   }

clang/lib/Frontend/InitPreprocessor.cpp

@@ -461,10 +461,15 @@ static void InitializeStandardPredefinedMacros(const TargetInfo &TI,
       Builder.defineMacro("__FAST_RELAXED_MATH__");
   }
 
-  if (LangOpts.SYCL) {
-    // SYCL Version is set to a value when building SYCL applications
-    if (LangOpts.SYCLVersion == 2017)
+  // SYCL Version is set to a value when building SYCL applications
+  switch (LangOpts.getSYCLVersion()) {
+    case LangOptions::SYCLVersionList::sycl_1_2_1:
       Builder.defineMacro("CL_SYCL_LANGUAGE_VERSION", "121");
+      break;
+    case LangOptions::SYCLVersionList::undefined:
+    default:
+      // This is not a SYCL source, nothing to add
+      break;
   }
 
   // Not "standard" per se, but available even with the -undef flag.

clang/test/CodeGen/wasm-call-main.c

@@ -0,0 +1,13 @@
+// RUN: %clang_cc1 -triple wasm32 -o - -emit-llvm %s | FileCheck %s
+
+// Mangle argc/argv main even when it's not defined in this TU.
+
+#include <stddef.h>
+
+int main(int argc, char *argv[]);
+
+int foo(void) {
+    return main(0, NULL);
+}
+
+// CHECK: call i32 @__main_argc_argv(