Optimize garbage collection with a generational GC

.github/workflows/build-and-test.yaml

@@ -406,6 +406,47 @@ jobs:
           library-arch: riscv32-linux-gnu-ilp32
           jit_target_arch: "riscv32"
 
+        # xtensa build (esp32, lx6)
+        - os: "ubuntu-24.04"
+          cc: "xtensa-lx6-linux-gnu-gcc"
+          cxx: "xtensa-lx6-linux-gnu-g++"
+          cflags: "-O2"
+          otp: "28"
+          elixir_version: "1.17"
+          rebar3_version: "3.24.0"
+          cmake_opts_other: "-DAVM_WARNINGS_ARE_ERRORS=ON -DCMAKE_TOOLCHAIN_FILE=${RUNNER_TEMP}/xtensa_toolchain.cmake"
+          compiler_pkgs: ""
+          arch: "xtensa"
+          library-arch: xtensa-lx6-linux-gnu
+
+        # xtensa build + jit (esp32, lx6)
+        - os: "ubuntu-24.04"
+          cc: "xtensa-lx6-linux-gnu-gcc"
+          cxx: "xtensa-lx6-linux-gnu-g++"
+          cflags: "-O2"
+          otp: "28"
+          elixir_version: "1.17"
+          rebar3_version: "3.24.0"
+          cmake_opts_other: "-DAVM_DISABLE_JIT=OFF -DAVM_JIT_TARGET_ARCH=xtensa -DCMAKE_TOOLCHAIN_FILE=${RUNNER_TEMP}/xtensa_toolchain.cmake"
+          compiler_pkgs: ""
+          arch: "xtensa"
+          library-arch: xtensa-lx6-linux-gnu
+          jit_target_arch: "xtensa"
+
+        # JIT + DWARF build (xtensa, esp32, lx6)
+        - os: "ubuntu-24.04"
+          cc: "xtensa-lx6-linux-gnu-gcc"
+          cxx: "xtensa-lx6-linux-gnu-g++"
+          cflags: "-O2"
+          otp: "28"
+          elixir_version: "1.17"
+          rebar3_version: "3.24.0"
+          cmake_opts_other: "-DAVM_DISABLE_JIT=OFF -DAVM_DISABLE_JIT_DWARF=OFF -DAVM_JIT_TARGET_ARCH=xtensa -DCMAKE_TOOLCHAIN_FILE=${RUNNER_TEMP}/xtensa_toolchain.cmake"
+          compiler_pkgs: ""
+          arch: "xtensa"
+          library-arch: xtensa-lx6-linux-gnu
+          jit_target_arch: "xtensa"
+
         # libsodium enabled build
         - os: "ubuntu-24.04"
           cc: "cc"
@@ -458,7 +499,7 @@ jobs:
       run: sudo dpkg --add-architecture i386
 
     - name: "Setup cross compilation architecture"
-      if: matrix.library-arch != '' && matrix.library-arch != 'riscv32-linux-gnu-ilp32'
+      if: matrix.library-arch != '' && matrix.library-arch != 'riscv32-linux-gnu-ilp32' && matrix.library-arch != 'xtensa-lx6-linux-gnu'
       run: |
         # Replace Azure mirrors with official Ubuntu repositories
         sudo sed -i 's|azure\.||g' /etc/apt/sources.list
@@ -583,6 +624,76 @@ jobs:
       env:
         GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
+    - name: "Setup cross compilation architecture (xtensa)"
+      if: matrix.library-arch == 'xtensa-lx6-linux-gnu'
+      run: |
+        sudo dpkg --add-architecture ${{ matrix.arch }}
+
+        # Download packages from pguyot/crossbuild-essential-xtensa
+        gh release download xtensa-toolchain-14.2.0.20260515 \
+          -R pguyot/crossbuild-essential-xtensa \
+          --pattern 'qemu-xtensa-esp_*.deb' \
+          --pattern 'xtensa-lx6-linux-gnu-toolchain_*.deb' \
+          --pattern 'libc6-lx6_*.deb' \
+          --pattern 'libc6-dev-lx6_*.deb' \
+          --pattern 'libc6-dbg-lx6_*.deb' \
+          --pattern 'zlib1g-lx6_*.deb' \
+          --pattern 'zlib1g-dev-lx6_*.deb' \
+          --pattern 'libmbedcrypto7-lx6_*.deb' \
+          --pattern 'libmbedx509-1-lx6_*.deb' \
+          --pattern 'libmbedtls14-lx6_*.deb' \
+          --pattern 'libmbedtls-dev-lx6_*.deb'
+
+        # Install QEMU with binfmt support (activates automatically on systemd)
+        sudo dpkg -i qemu-xtensa-esp_*.deb
+
+        # Install toolchain and add to PATH
+        sudo dpkg -i xtensa-lx6-linux-gnu-toolchain_*.deb
+        echo "/opt/xtensa-lx6/bin" >> $GITHUB_PATH
+
+        # Install runtime libraries
+        sudo dpkg -i libc6-lx6_*.deb
+        sudo dpkg -i libc6-dev-lx6_*.deb
+        sudo dpkg -i libc6-dbg-lx6_*.deb
+        sudo dpkg -i zlib1g-lx6_*.deb
+        sudo dpkg -i zlib1g-dev-lx6_*.deb
+        sudo dpkg -i libmbedcrypto7-lx6_*.deb
+        sudo dpkg -i libmbedx509-1-lx6_*.deb
+        sudo dpkg -i libmbedtls14-lx6_*.deb
+        sudo dpkg -i libmbedtls-dev-lx6_*.deb
+
+        # Create CMake toolchain file
+        cat > ${RUNNER_TEMP}/xtensa_toolchain.cmake <<'EOF'
+        set(CMAKE_SYSTEM_NAME Linux)
+        set(CMAKE_SYSTEM_PROCESSOR xtensa)
+
+        set(CMAKE_C_COMPILER /opt/xtensa-lx6/bin/xtensa-lx6-linux-gnu-gcc)
+        set(CMAKE_CXX_COMPILER /opt/xtensa-lx6/bin/xtensa-lx6-linux-gnu-g++)
+
+        set(CMAKE_SYSROOT /opt/xtensa-lx6/xtensa-lx6-linux-gnu/sysroot)
+        list(APPEND CMAKE_FIND_ROOT_PATH /usr)
+        set(CMAKE_C_LIBRARY_ARCHITECTURE xtensa-lx6-linux-gnu)
+
+        include_directories(SYSTEM /usr/xtensa-lx6-linux-gnu/include)
+
+        set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+        set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+        set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+        set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)
+
+        set(ZLIB_LIBRARY /usr/xtensa-lx6-linux-gnu/lib/libz.so)
+        set(MBEDTLS_ROOT_DIR /usr)
+        set(MBEDTLS_LIBRARIES_DIR /usr/xtensa-lx6-linux-gnu/lib)
+        EOF
+
+        # Register binfmt if not activated automatically
+        if [ ! -f /proc/sys/fs/binfmt_misc/qemu-xtensa-esp32 ]; then
+          echo ':qemu-xtensa-esp32:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x5e\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-xtensa:' | sudo tee /proc/sys/fs/binfmt_misc/register || true
+        fi
+
+      env:
+        GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
     - name: "APT update"
       run: sudo apt update -y
 
@@ -818,7 +929,7 @@ jobs:
         valgrind --error-exitcode=1 ./src/AtomVM tests/libs/jit/test_jit.avm
 
     - name: "Test: test_jit.avm"
-      timeout-minutes: 60
+      timeout-minutes: 120
       working-directory: build
       run: |
         ulimit -c unlimited

.github/workflows/esp32-build.yaml

@@ -51,20 +51,36 @@ jobs:
          - 'v5.3.4'
          - 'v5.4.3'
          - 'v5.5.3'
+        jit: [false]
 
         include:
         - esp-idf-target: "esp32p4"
           idf-version: 'v5.4.4'
+          jit: false
         - esp-idf-target: "esp32p4"
           idf-version: 'v5.5.3'
+          jit: false
         - esp-idf-target: "esp32s3"
           idf-version: 'v5.5.3'
+          jit: false
         - esp-idf-target: "esp32s3"
           idf-version: 'v5.5.3'
           usb-serial: 'ON'
+          jit: false
         - esp-idf-target: "esp32"
           idf-version: 'v5.4.3'
           libsodium: 'ON'
+          jit: false
+        # JIT builds (v5.5.3 only)
+        - esp-idf-target: "esp32c3"
+          idf-version: 'v5.5.3'
+          jit: true
+        - esp-idf-target: "esp32"
+          idf-version: 'v5.5.3'
+          jit: true
+        - esp-idf-target: "esp32s3"
+          idf-version: 'v5.5.3'
+          jit: true
 
     steps:
     - name: Checkout repo
@@ -105,8 +121,13 @@ jobs:
           echo 'CONFIG_USE_USB_SERIAL=y' >> sdkconfig.defaults.in
         fi
         export IDF_TARGET=${{matrix.esp-idf-target}}
-        idf.py set-target ${{matrix.esp-idf-target}}
-        idf.py ${{ matrix.libsodium == 'ON' && '-DAVM_USE_LIBSODIUM=ON' || '' }} build
+        if [ "${{ matrix.jit }}" = "true" ]; then
+          SDKCONFIG_DEFAULTS="sdkconfig.defaults;sdkconfig.jit" idf.py set-target ${{matrix.esp-idf-target}}
+          SDKCONFIG_DEFAULTS="sdkconfig.defaults;sdkconfig.jit" idf.py build
+        else
+          idf.py set-target ${{matrix.esp-idf-target}}
+          idf.py ${{ matrix.libsodium == 'ON' && '-DAVM_USE_LIBSODIUM=ON' || '' }} build
+        fi
         idf.py size
 
     - name: Print component size info with idf.py
@@ -216,6 +237,9 @@ jobs:
         echo "CONFIG_HEAP_POISONING_COMPREHENSIVE=y" >> sdkconfig.defaults
         echo "CONFIG_ESP_WIFI_IRAM_OPT=n" >> sdkconfig.defaults
         echo "CONFIG_ESP_WIFI_RX_IRAM_OPT=n" >> sdkconfig.defaults
+        if [ "${{ matrix.jit }}" = "true" ]; then
+          echo "CONFIG_JIT_ENABLED=y" >> sdkconfig.defaults
+        fi
         . $IDF_PATH/export.sh
         export IDF_TARGET=${{matrix.esp-idf-target}}
         idf.py set-target ${{matrix.esp-idf-target}}
@@ -239,7 +263,7 @@ jobs:
       if: failure() && matrix.esp-idf-target != 'esp32p4'
       uses: actions/upload-artifact@v4
       with:
-        name: atomvm-esp32-test-${{ matrix.esp-idf-target }}-${{ matrix.idf-version }}-memcheck.elf
+        name: atomvm-esp32-test-${{ matrix.esp-idf-target }}-${{ matrix.idf-version }}${{ matrix.jit && '-jit' || '' }}-memcheck.elf
         path: ./src/platforms/esp32/test/build/atomvm-esp32-test.elf
         if-no-files-found: error
 
@@ -252,6 +276,10 @@ jobs:
         . $IDF_PATH/export.sh
         export IDF_TARGET=${{matrix.esp-idf-target}}
         export PATH=${PATH}:${HOME}/.cache/rebar3/bin
+        cp sdkconfig.defaults sdkconfig.defaults.backup
+        if [ "${{ matrix.jit }}" = "true" ]; then
+          echo "CONFIG_JIT_ENABLED=y" >> sdkconfig.defaults
+        fi
         idf.py set-target ${{matrix.esp-idf-target}}
         idf.py build
 
@@ -265,12 +293,13 @@ jobs:
         . $IDF_PATH/export.sh
         export PATH=/opt/qemu/bin:${PATH}
         pytest --target=${{matrix.esp-idf-target}} --embedded-services=idf,qemu -s
+        cp sdkconfig.defaults.backup sdkconfig.defaults
 
     - name: Upload ESP32 tests ELF artifact
       # TODO: remove the following exclusion when ESP32P4 support is added to espressif/qemu
       if: failure() && matrix.esp-idf-target != 'esp32p4'
       uses: actions/upload-artifact@v4
       with:
-        name: atomvm-esp32-test-${{ matrix.esp-idf-target }}-${{ matrix.idf-version }}.elf
+        name: atomvm-esp32-test-${{ matrix.esp-idf-target }}-${{ matrix.idf-version }}${{ matrix.jit && '-jit' || '' }}.elf
         path: ./src/platforms/esp32/test/build/atomvm-esp32-test.elf
         if-no-files-found: error

CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added `"USB_SERIAL_JTAG"` peripheral to the ESP32 `uart` module on chips with a built-in
   USB-Serial-JTAG controller (C3/C5/C6/C61/H2/H21/H4/P4/S3)
 - Added support for the `safe` option in `erlang:binary_to_term/2`
+- Added xtensa JIT backend for esp32 platform
 
 ### Changed
 - Updated network type db() to dbm() to reflect the actual representation of the type

CMakeLists.txt

@@ -61,12 +61,14 @@ if (NOT AVM_DISABLE_JIT AND NOT DEFINED AVM_JIT_TARGET_ARCH)
         set(AVM_JIT_TARGET_ARCH "arm32")
     elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^riscv64$")
         set(AVM_JIT_TARGET_ARCH "riscv64")
+    elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^xtensa")
+        set(AVM_JIT_TARGET_ARCH "xtensa")
     else()
         message(FATAL_ERROR "JIT is not supported on ${CMAKE_SYSTEM_PROCESSOR}")
     endif()
 endif()
 
-set(AVM_PRECOMPILED_TARGETS "x86_64;aarch64;arm32;armv6m;armv6m+float32;armv6m+thumb2;riscv32;riscv64;wasm32" CACHE STRING "Targets to precompile code to if AVM_DISABLE_JIT is OFF or AVM_ENABLE_PRECOMPILED is ON")
+set(AVM_PRECOMPILED_TARGETS "x86_64;aarch64;arm32;armv6m;armv6m+thumb2;armv6m+thumb2+float32;riscv32;riscv64;wasm32;xtensa;xtensa+float32" CACHE STRING "Targets to precompile code to if AVM_DISABLE_JIT is OFF or AVM_ENABLE_PRECOMPILED is ON")
 
 # DWARF is not supported on wasm32
 if (NOT AVM_DISABLE_JIT_DWARF)