[RISC-V] Build coredistools (#387)

Needed for R2RDump --disasm

Part of dotnet/runtime#84834
cc @wscho77 @HJLeee @clamp03 @JongHeonChoi @t-mustafin @gbalykov
@viewizard @ashaurtaev @brucehoult @sirntar @yurai007 @bajtazar

build-coredistools.sh

@@ -17,14 +17,13 @@ CMakeOSXArchitectures=
 LLVMTargetsToBuild="AArch64;ARM;X86"
 
 # Figure out which `strip` to use. Prefer `llvm-strip` if it is available.
-# `llvm-strip` is available in CBL-Mariner container; `strip` is available on macOS.
-StripTool=$(command -v llvm-strip)
+# `llvm-strip` is available in CBL-Mariner container,
+# `llvm-strip-<version>` is available on standard cross build Ubuntu container,
+# `strip` is available on macOS.
+StripTool=$(command -v llvm-strip{,-{20..15}} strip | head -n 1)
 if [ -z "$StripTool" ]; then
-    StripTool=$(command -v strip)
-    if [ -z "$StripTool" ]; then
     echo "Strip tool not found"
     exit 1
-    fi
 fi
 
 TblGenTool=$(command -v llvm-tblgen)
@@ -33,13 +32,14 @@ if [ -z "$TblGenTool" ]; then
     exit 1
 fi
 
-C_COMPILER=$(command -v clang)
+# Take first match from: clang clang-20 clang-19 .. clang-15
+C_COMPILER=$(command -v clang{,-{20..15}} | head -n 1)
 if [ -z "$C_COMPILER" ]; then
     echo "C compiler not found"
     # Keep going in case cmake can find one?
 fi
 
-CXX_COMPILER=$(command -v clang++)
+CXX_COMPILER=$(command -v clang++{,-{20..15}} | head -n 1)
 if [ -z "$CXX_COMPILER" ]; then
     echo "C++ compiler not found"
     # Keep going in case cmake can find one?
@@ -79,6 +79,13 @@ case "$TargetOSArchitecture" in
         LLVMTargetsToBuild="LoongArch"
         ;;
 
+    linux-riscv64)
+        CMakeCrossCompiling=ON
+        LLVMHostTriple=riscv64-linux-gnu
+        LLVMTargetsToBuild="RISCV"
+        EnsureCrossRootfsDirectoryExists
+        ;;
+
     osx-arm64)
         CMakeCrossCompiling=ON
         CMakeOSXArchitectures=arm64

build-tblgen.sh

@@ -70,14 +70,18 @@ fi
 
 pushd "$BinariesDirectory"
 
+# Take first match from: clang clang-20 clang-19 .. clang-15
+C_COMPILER=$(command -v clang{,-{20..15}} | head -n 1)
+CXX_COMPILER=$(command -v clang++{,-{20..15}} | head -n 1)
+
 if [ -z "$CrossRootfsDirectory" ]; then
     BUILD_FLAGS=""
     cmake \
         -G "Unix Makefiles" \
         -DCMAKE_BUILD_TYPE=Release \
         -DCMAKE_CROSSCOMPILING=$CMakeCrossCompiling \
-        -DCMAKE_C_COMPILER=$(command -v clang) \
-        -DCMAKE_CXX_COMPILER=$(command -v clang++) \
+        -DCMAKE_C_COMPILER=$C_COMPILER \
+        -DCMAKE_CXX_COMPILER=$CXX_COMPILER \
         -DCMAKE_C_FLAGS="${BUILD_FLAGS}" \
         -DCMAKE_CXX_FLAGS="${BUILD_FLAGS}" \
         -DCMAKE_INSTALL_PREFIX=$RootDirectory \
@@ -92,8 +96,8 @@ elif [ $CrossBuildUsingMariner -eq 1 ]; then
         -DCMAKE_BUILD_TYPE=Release \
         -DCMAKE_INSTALL_PREFIX=$RootDirectory \
         -DCMAKE_CROSSCOMPILING=$CMakeCrossCompiling \
-        -DCMAKE_C_COMPILER=$(command -v clang) \
-        -DCMAKE_CXX_COMPILER=$(command -v clang++) \
+        -DCMAKE_C_COMPILER=$C_COMPILER \
+        -DCMAKE_CXX_COMPILER=$CXX_COMPILER \
         -DCMAKE_C_FLAGS="${BUILD_FLAGS}" \
         -DCMAKE_CXX_FLAGS="${BUILD_FLAGS}" \
         -DCMAKE_EXE_LINKER_FLAGS="-fuse-ld=lld" \
@@ -109,8 +113,8 @@ else
         -DCMAKE_BUILD_TYPE=Release \
         -DCMAKE_INSTALL_PREFIX=$RootDirectory \
         -DCMAKE_CROSSCOMPILING=$CMakeCrossCompiling \
-        -DCMAKE_C_COMPILER=$(command -v clang) \
-        -DCMAKE_CXX_COMPILER=$(command -v clang++) \
+        -DCMAKE_C_COMPILER=$C_COMPILER \
+        -DCMAKE_CXX_COMPILER=$CXX_COMPILER \
         -DCMAKE_C_FLAGS="${BUILD_FLAGS}" \
         -DCMAKE_CXX_FLAGS="${BUILD_FLAGS}" \
         -DCMAKE_INCLUDE_PATH=$CrossRootfsDirectory/usr/include \

doc/building-coredistools.md

@@ -105,3 +105,17 @@ sudo tdnf install -y ncurses-compat
 export PATH=$(pwd)/bin:$PATH
 ./build-coredistools.sh linux-arm /crossrootfs/arm
 ```
+
+8. Build `libcoredistools.so` for Linux riscv64 under Docker:  
+There is no CBL Mariner container for RISC-V so use the standard Ubuntu cross build container used for e.g. dotnet/runtime.
+```
+docker run -it --rm --entrypoint /bin/bash -v ~/git/jitutils:/opt/code -w /opt/code mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-22.04-cross-riscv64
+apt install libtinfo5
+
+# If you haven't built llvm-tblgen in step 5, you can do so in the same docker (pass "/" as crossrootfs).
+./build-tblgen.sh linux-x64 /
+
+# Now, the main course
+export PATH=$(pwd)/bin:$PATH
+./build-coredistools.sh linux-riscv64 /crossrootfs/riscv64
+```

src/coredistools/coredistools.cpp

@@ -286,6 +286,9 @@ bool CorDisasm::setTarget() {
     case Triple::loongarch64:
       TheTargetArch = Target_LoongArch64;
       break;
+    case Triple::riscv64:
+      TheTargetArch = Target_RiscV64;
+      break;
     default:
       Print->Error("Unsupported Architecture: %s\n",
                    Triple::getArchTypeName(TheTriple->getArch()));
@@ -309,6 +312,9 @@ bool CorDisasm::setTarget() {
   case Target_LoongArch64:
     TheTriple->setArch(Triple::loongarch64);
     break;
+  case Target_RiscV64:
+    TheTriple->setArch(Triple::riscv64);
+    break;
   default:
     Print->Error("Unsupported Architecture: %s\n",
                  Triple::getArchTypeName(TheTriple->getArch()));

src/coredistools/coredistools.h

@@ -42,7 +42,8 @@ enum TargetArch {
     Target_X64,
     Target_Thumb,
     Target_Arm64,
-    Target_LoongArch64
+    Target_LoongArch64,
+    Target_RiscV64,
 };
 
 struct CorDisasm;