[Clang] Enable RISC-V support for Fuchsia

[phosek]

Summary

We don't have a full sysroot yet, so for now we only include compiler
support and compiler-rt builtins, the rest of the runtimes will get
enabled later.

[lenary]

clang/cmake/caches/Fuchsia-stage2.cmake

130

I don't know what's preventing you from enabling compiling the runtimes. I made a cmake config that built the runtimes, in part based off the fuschia config in this file.

I suppose this requires you to have a RISC-V sysroot, which you may not have.

[phosek]

clang/cmake/caches/Fuchsia-stage2.cmake

130

Correct, as mentioned in the summary of this change, we don't have a sysroot yet. Once the sysroot is ready, we'll enable runtimes as well in a follow up change.

clang/cmake/caches/Fuchsia-stage2.cmake

 # This file sets up a CMakeCache for the second stage of a Fuchsia toolchain build.
 
-set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64 CACHE STRING "")
+set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64;RISCV CACHE STRING "")
 
 set(PACKAGE_VENDOR Fuchsia CACHE STRING "")
 
 set(LLVM_ENABLE_BACKTRACES OFF CACHE BOOL "")
 if(NOT APPLE)
   set(LLVM_ENABLE_LLD ON CACHE BOOL "")
 endif()
 set(LLVM_ENABLE_LTO ON CACHE BOOL "")
if(LINUX_${target}_SYSROOT)
     # Use .build-id link.
     list(APPEND RUNTIME_BUILD_ID_LINK "${target}")
   endif()
 endforeach()
 
 if(FUCHSIA_SDK)
   set(FUCHSIA_aarch64_NAME arm64)
   set(FUCHSIA_x86_64_NAME x64)
-  foreach(target x86_64;aarch64)
+  set(FUCHSIA_riscv64_NAME riscv64)
+  foreach(target x86_64;aarch64;riscv64)
     set(FUCHSIA_${target}_COMPILER_FLAGS "-I${FUCHSIA_SDK}/pkg/fdio/include")
     set(FUCHSIA_${target}_LINKER_FLAGS "-L${FUCHSIA_SDK}/arch/${FUCHSIA_${target}_NAME}/lib")
     set(FUCHSIA_${target}_SYSROOT "${FUCHSIA_SDK}/arch/${FUCHSIA_${target}_NAME}/sysroot")
   endforeach()
 
-  foreach(target x86_64;aarch64)
+  foreach(target x86_64;aarch64;riscv64)
     # Set the per-target builtins options.
     list(APPEND BUILTIN_TARGETS "${target}-unknown-fuchsia")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_SYSTEM_NAME Fuchsia CACHE STRING "")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_ASM_FLAGS ${FUCHSIA_${target}_COMPILER_FLAGS} CACHE STRING "")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_C_FLAGS ${FUCHSIA_${target}_COMPILER_FLAGS} CACHE STRING "")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_CXX_FLAGS ${FUCHSIA_${target}_COMPILER_FLAGS} CACHE STRING "")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_SHARED_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE STRING "")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_MODULE_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE STRING "")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_EXE_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE STRING "")
     set(BUILTINS_${target}-unknown-fuchsia_CMAKE_SYSROOT ${FUCHSIA_${target}_SYSROOT} CACHE PATH "")
+  endforeach()
 
+  foreach(target x86_64;aarch64)
     # Set the per-target runtimes options.
     list(APPEND RUNTIME_TARGETS "${target}-unknown-fuchsia")
     set(RUNTIMES_${target}-unknown-fuchsia_CMAKE_SYSTEM_NAME Fuchsia CACHE STRING "")
     set(RUNTIMES_${target}-unknown-fuchsia_CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "")
     set(RUNTIMES_${target}-unknown-fuchsia_CMAKE_BUILD_WITH_INSTALL_RPATH ON CACHE BOOL "")
     set(RUNTIMES_${target}-unknown-fuchsia_CMAKE_ASM_FLAGS ${FUCHSIA_${target}_COMPILER_FLAGS} CACHE STRING "")
     set(RUNTIMES_${target}-unknown-fuchsia_CMAKE_C_FLAGS ${FUCHSIA_${target}_COMPILER_FLAGS} CACHE STRING "")
     set(RUNTIMES_${target}-unknown-fuchsia_CMAKE_CXX_FLAGS ${FUCHSIA_${target}_COMPILER_FLAGS} CACHE STRING "")

clang/cmake/caches/Fuchsia.cmake

 # This file sets up a CMakeCache for a Fuchsia toolchain build.
 
-set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64 CACHE STRING "")
+set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64;RISCV CACHE STRING "")
 
 set(PACKAGE_VENDOR Fuchsia CACHE STRING "")
 
 set(LLVM_ENABLE_BACKTRACES OFF CACHE BOOL "")
 set(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR ON CACHE BOOL "")
 set(LLVM_ENABLE_TERMINFO OFF CACHE BOOL "")
 set(LLVM_ENABLE_UNWIND_TABLES OFF CACHE BOOL "")
 set(LLVM_ENABLE_ZLIB OFF CACHE BOOL "")

clang/lib/Basic/Targets.cpp

default:
       return new RISCV32TargetInfo(Triple, Opts);
     }
 
   case llvm::Triple::riscv64:
     // TODO: add cases for NetBSD, RTEMS once tested.
     switch (os) {
     case llvm::Triple::FreeBSD:
       return new FreeBSDTargetInfo<RISCV64TargetInfo>(Triple, Opts);
+    case llvm::Triple::Fuchsia:
+      return new FuchsiaTargetInfo<RISCV64TargetInfo>(Triple, Opts);
     case llvm::Triple::Linux:
       return new LinuxTargetInfo<RISCV64TargetInfo>(Triple, Opts);
     default:
       return new RISCV64TargetInfo(Triple, Opts);
     }
 
   case llvm::Triple::sparc:
     switch (os) {

clang/lib/Driver/ToolChains/Fuchsia.cpp

if (!SelectedMultilib.isDefault())
         for (const auto &Path : PathsCallback(SelectedMultilib))
           // Prepend the multilib path to ensure it takes the precedence.
           getFilePaths().insert(getFilePaths().begin(), Path);
 }
 
 std::string Fuchsia::ComputeEffectiveClangTriple(const ArgList &Args,
                                                  types::ID InputType) const {
   llvm::Triple Triple(ComputeLLVMTriple(Args, InputType));
-  return (Triple.getArchName() + "-" + Triple.getOSName()).str();
+  return Triple.str();
 }
 
 Tool *Fuchsia::buildLinker() const {
   return new tools::fuchsia::Linker(*this);
 }
 
 ToolChain::RuntimeLibType Fuchsia::GetRuntimeLibType(
     const ArgList &Args) const {
SanitizerMask Fuchsia::getSupportedSanitizers() const {
   Res |= SanitizerKind::FuzzerNoLink;
   Res |= SanitizerKind::SafeStack;
   Res |= SanitizerKind::Scudo;
   return Res;
 }
 
 SanitizerMask Fuchsia::getDefaultSanitizers() const {
   SanitizerMask Res;
-  if (getTriple().getArch() == llvm::Triple::aarch64)
+  switch (getTriple().getArch()) {
+  case llvm::Triple::aarch64:
     Res |= SanitizerKind::ShadowCallStack;
-  else
+    break;
+  case llvm::Triple::x86_64:
     Res |= SanitizerKind::SafeStack;
+    break;
+  case llvm::Triple::riscv64:
+    break;
+  default:
+    llvm_unreachable("invalid architecture");
+  }
   return Res;
 }

clang/test/Driver/fuchsia.c

 // RUN: %clang %s -### -no-canonical-prefixes --target=x86_64-fuchsia \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
 // RUN:     | FileCheck -check-prefixes=CHECK,CHECK-X86_64 %s
 // RUN: %clang %s -### -no-canonical-prefixes --target=aarch64-fuchsia \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
 // RUN:     | FileCheck -check-prefixes=CHECK,CHECK-AARCH64 %s
+// RUN: %clang %s -### -no-canonical-prefixes --target=riscv64-fuchsia \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-RISCV64 %s
 // CHECK: {{.*}}clang{{.*}}" "-cc1"
+// CHECK-X86_64: "-triple" "x86_64-unknown-fuchsia"
+// CHECK-AARCH64: "-triple" "aarch64-unknown-fuchsia"
+// CHECK-RISCV64: "-triple" "riscv64-unknown-fuchsia"
 // CHECK: "--mrelax-relocations"
 // CHECK: "-munwind-tables"
 // CHECK: "-fuse-init-array"
 // CHECK: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
 // CHECK: "-isysroot" "[[SYSROOT:[^"]+]]"
 // CHECK: "-internal-externc-isystem" "[[SYSROOT]]{{/|\\\\}}include"
 // CHECK-AARCH64: "-fsanitize=shadow-call-stack"
 // CHECK-X86_64: "-fsanitize=safe-stack"
 // CHECK: "-stack-protector" "2"
 // CHECK: "-fno-common"
 // CHECK: {{.*}}ld.lld{{.*}}" "-z" "rodynamic" "-z" "separate-loadable-segments"
 // CHECK: "--sysroot=[[SYSROOT]]"
 // CHECK: "-pie"
 // CHECK: "--build-id"
 // CHECK: "--hash-style=gnu"
 // CHECK: "-dynamic-linker" "ld.so.1"
 // CHECK: Scrt1.o
 // CHECK-NOT: crti.o
 // CHECK-NOT: crtbegin.o
 // CHECK: "-L[[SYSROOT]]{{/|\\\\}}lib"
 // CHECK-X86_64: "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}libclang_rt.builtins.a"
 // CHECK-AARCH64: "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}aarch64-fuchsia{{/|\\\\}}libclang_rt.builtins.a"
+// CHECK-RISCV64: "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}riscv64-fuchsia{{/|\\\\}}libclang_rt.builtins.a"
 // CHECK: "-lc"
 // CHECK-NOT: crtend.o
 // CHECK-NOT: crtn.o
 
 // RUN: %clang %s -### --target=x86_64-fuchsia -rtlib=libgcc -fuse-ld=lld 2>&1 \
 // RUN:     | FileCheck %s -check-prefix=CHECK-RTLIB
 // CHECK-RTLIB: error: invalid runtime library name in argument '-rtlib=libgcc'
 

clang/test/Driver/fuchsia.cpp

 // RUN: %clangxx %s -### -no-canonical-prefixes --target=x86_64-fuchsia \
 // RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
-// RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 | FileCheck %s
+// RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-X86_64 %s
+// RUN: %clangxx %s -### -no-canonical-prefixes --target=aarch64-fuchsia \
+// RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-AARCH64 %s
+// RUN: %clangxx %s -### -no-canonical-prefixes --target=riscv64-fuchsia \
+// RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-RISCV64 %s
 // CHECK: {{.*}}clang{{.*}}" "-cc1"
-// CHECK: "-triple" "x86_64-fuchsia"
+// CHECK-X86_64: "-triple" "x86_64-unknown-fuchsia"
+// CHECK-AARCH64: "-triple" "aarch64-unknown-fuchsia"
+// CHECK-RISCV64: "-triple" "riscv64-unknown-fuchsia"
 // CHECK: "-fuse-init-array"
 // CHECK: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
 // CHECK: "-isysroot" "[[SYSROOT:[^"]+]]"
 // CHECK: "-internal-isystem" "{{.*[/\\]}}include{{/|\\\\}}c++{{/|\\\\}}v1"
 // CHECK: "-internal-externc-isystem" "[[SYSROOT]]{{/|\\\\}}include"
 // CHECK: {{.*}}ld.lld{{.*}}" "-z" "rodynamic"
 // CHECK: "--sysroot=[[SYSROOT]]"
 // CHECK: "-pie"
 // CHECK: "--build-id"
 // CHECK: "-dynamic-linker" "ld.so.1"
 // CHECK: Scrt1.o
 // CHECK-NOT: crti.o
 // CHECK-NOT: crtbegin.o
 // CHECK: "-L[[SYSROOT]]{{/|\\\\}}lib"
 // CHECK: "--push-state"
 // CHECK: "--as-needed"
 // CHECK: "-lc++"
 // CHECK: "-lm"
 // CHECK: "--pop-state"
-// CHECK: "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}libclang_rt.builtins.a"
+// CHECK-X86_64: "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}libclang_rt.builtins.a"
+// CHECK-AARCH64: "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}aarch64-fuchsia{{/|\\\\}}libclang_rt.builtins.a"
+// CHECK-RISCV64: "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}riscv64-fuchsia{{/|\\\\}}libclang_rt.builtins.a"
 // CHECK: "-lc"
 // CHECK-NOT: crtend.o
 // CHECK-NOT: crtn.o
 
 // RUN: %clangxx %s -### --target=x86_64-unknown-fuchsia -stdlib=libstdc++ \
 // RUN:     -fuse-ld=lld 2>&1 \
 // RUN:     | FileCheck %s -check-prefix=CHECK-STDLIB
 // CHECK-STDLIB: error: invalid library name in argument '-stdlib=libstdc++'