[PATCH] [PATCH] Enable targeting riscv64-linux-android

[hiraditya]

Summary

Putting: https://android.googlesource.com/toolchain/llvm_android/+/refs/heads/master/patches/Enable-targeting-riscv64-linux-android.patch for review.

Authored by: Colin Cross <[e-mail]>

[enh]

clang/lib/Driver/ToolChains/Linux.cpp

95–96

(we should remove this and mips64 at some point...)

[phosek]

clang/lib/Driver/ToolChains/Linux.cpp

129–130

Is there a test that covers this function? If yes, it should be updated to also cover this branch. If no, then we should consider introducing one (although that could be done in a separate change).

[hiraditya]

clang/lib/Driver/ToolChains/Linux.cpp

95–96

will do in a follow up patch. thanks!

129–130

good point. i'll update/add testcase as appropriate in a separate patch. Thanks for bringing this up.

[phosek]

LGTM

[MaskRay]

clang/lib/Driver/ToolChains/Linux.cpp

129–130

This function is a gloss hack for Debian style multiarch library paths (there is no "vendor" part in the target triples). It's frowned upon and the code is somehow shared with Android as well. It'd be best if Android can move away touching this function.

You may try removing Android customization and see what may break.

[enh]

clang/lib/Driver/ToolChains/Linux.cpp

129–130

we use this to specify what target api level you're targeting. so a developer will say "x86-linux-android28" or whatever. (we're effectively "multiarch" ourselves, but more so, because we have a new one every year.)

clang/lib/Driver/ToolChains/Linux.cpp

case llvm::Triple::aarch64_be:
     return "aarch64_be-linux-gnu";
 
   case llvm::Triple::m68k:
     return "m68k-linux-gnu";
 
   case llvm::Triple::mips:
     return IsMipsR6 ? "mipsisa32r6-linux-gnu" : "mips-linux-gnu";
   case llvm::Triple::mipsel:
     if (IsAndroid)
       return "mipsel-linux-android";
     return IsMipsR6 ? "mipsisa32r6el-linux-gnu" : "mipsel-linux-gnu";
   case llvm::Triple::mips64: {
     std::string MT = std::string(IsMipsR6 ? "mipsisa64r6" : "mips64") +
                      "-linux-" + (IsMipsN32Abi ? "gnuabin32" : "gnuabi64");
     if (D.getVFS().exists(concat(SysRoot, "/lib", MT)))
       return MT;
     if (D.getVFS().exists(concat(SysRoot, "/lib/mips64-linux-gnu")))
       return "mips64-linux-gnu";
case llvm::Triple::ppc:
     return "powerpc-linux-gnu";
   case llvm::Triple::ppcle:
     return "powerpcle-linux-gnu";
   case llvm::Triple::ppc64:
     return "powerpc64-linux-gnu";
   case llvm::Triple::ppc64le:
     return "powerpc64le-linux-gnu";
   case llvm::Triple::riscv64:
+    if (IsAndroid)
+      return "riscv64-linux-android";
     return "riscv64-linux-gnu";
   case llvm::Triple::sparc:
     return "sparc-linux-gnu";
   case llvm::Triple::sparcv9:
     return "sparc64-linux-gnu";
   case llvm::Triple::systemz:
     return "s390x-linux-gnu";
   }

compiler-rt/cmake/Modules/AllSupportedArchDefs.cmake

else()
   set(OS_NAME "${CMAKE_SYSTEM_NAME}")
 endif()
 
 if(OS_NAME MATCHES "Linux")
   set(ALL_FUZZER_SUPPORTED_ARCH ${X86} ${X86_64} ${ARM32} ${ARM64} ${S390X})
 elseif (OS_NAME MATCHES "Windows")
   set(ALL_FUZZER_SUPPORTED_ARCH ${X86} ${X86_64})
 elseif(OS_NAME MATCHES "Android")
-  set(ALL_FUZZER_SUPPORTED_ARCH ${X86} ${X86_64} ${ARM32} ${ARM64})
+  set(ALL_FUZZER_SUPPORTED_ARCH ${X86} ${X86_64} ${ARM32} ${ARM64} ${RISCV64})
 else()
   set(ALL_FUZZER_SUPPORTED_ARCH ${X86_64} ${ARM64})
 endif()
 
 set(ALL_GWP_ASAN_SUPPORTED_ARCH ${X86} ${X86_64} ${ARM32} ${ARM64})
 if(APPLE)
   set(ALL_LSAN_SUPPORTED_ARCH ${X86} ${X86_64} ${MIPS64} ${ARM64})
 else()

compiler-rt/lib/sanitizer_common/sanitizer_linux.h

 // optimized for v1.
 # define __get_tls() \
     ({ register void** __v asm("v1"); \
        __asm__(".set    push\n" \
                ".set    mips32r2\n" \
                "rdhwr   %0,$29\n" \
                ".set    pop\n" : "=r"(__v)); \
        __v; })
+#elif defined (__riscv)
+# define __get_tls() \
+    ({ void** __v; __asm__("mv %0, tp" : "=r"(__v)); __v; })
 #elif defined(__i386__)
 # define __get_tls() \
     ({ void** __v; __asm__("movl %%gs:0, %0" : "=r"(__v)); __v; })
 #elif defined(__x86_64__)
 # define __get_tls() \
     ({ void** __v; __asm__("mov %%fs:0, %0" : "=r"(__v)); __v; })
 #else
 #error "Unsupported architecture."