Enable MLDSA dead-code elimination

Enable dead-code elimination for ML-DSA program builds

Signed-off-by: Ben Taylor <ben.taylor@linaro.org>

Author: Ben Taylor

core/CMakeLists.txt

@@ -115,6 +115,11 @@ if(USE_STATIC_TF_PSA_CRYPTO_LIBRARY)
         ${target_objects})
     tf_psa_crypto_set_base_compile_options(${tfpsacrypto_static_target})
     tf_psa_crypto_set_extra_compile_options(${tfpsacrypto_static_target})
+    if(CMAKE_COMPILER_IS_GNU OR CMAKE_COMPILER_IS_CLANG)
+        target_compile_options(${tfpsacrypto_static_target} PRIVATE
+            -ffunction-sections
+            -fdata-sections)
+    endif()
     set_target_properties(${tfpsacrypto_static_target} PROPERTIES OUTPUT_NAME tfpsacrypto)
     target_link_libraries(${tfpsacrypto_static_target} PUBLIC ${libs})
 
@@ -138,6 +143,11 @@ if(USE_SHARED_TF_PSA_CRYPTO_LIBRARY)
         ${target_objects})
     tf_psa_crypto_set_base_compile_options(${tfpsacrypto_target})
     tf_psa_crypto_set_extra_compile_options(${tfpsacrypto_target})
+    if(CMAKE_COMPILER_IS_GNU OR CMAKE_COMPILER_IS_CLANG)
+        target_compile_options(${tfpsacrypto_target} PRIVATE
+            -ffunction-sections
+            -fdata-sections)
+    endif()
     set_target_properties(${tfpsacrypto_target} PROPERTIES VERSION ${TF_PSA_CRYPTO_VERSION} SOVERSION ${TF_PSA_CRYPTO_SOVERSION})
     target_link_libraries(${tfpsacrypto_target} PUBLIC ${libs})
 

drivers/pqcp/CMakeLists.txt

@@ -11,4 +11,9 @@ foreach (target IN LISTS target_libraries)
         PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src
         PRIVATE mldsa-native/mldsa
     )
+    if(CMAKE_COMPILER_IS_GNU OR CMAKE_COMPILER_IS_CLANG)
+        target_compile_options(${target} PRIVATE
+            -ffunction-sections
+            -fdata-sections)
+    endif()
 endforeach(target)

programs/mldsa/CMakeLists.txt

@@ -1,10 +1,18 @@
+function(tfpsacrypto_mldsa_enable_dead_code_elimination exe)
+    if(CMAKE_COMPILER_IS_GNU OR CMAKE_COMPILER_IS_CLANG)
+        set_property(TARGET ${exe} APPEND_STRING PROPERTY
+            LINK_FLAGS " -Wl,--gc-sections")
+    endif()
+endfunction()
+
 # mldsa_export_pubkey
 tfpsacrypto_build_program_common(mldsa_export_public mldsa_export_public.c asn1_file_io.c)
 target_include_directories(mldsa_export_public PRIVATE
       ${PROJECT_SOURCE_DIR}/drivers/pqcp/src
       ${PROJECT_SOURCE_DIR}/drivers/pqcp/mldsa-native/mldsa/
 )
 
+tfpsacrypto_mldsa_enable_dead_code_elimination(mldsa_export_public)
 target_link_libraries(mldsa_export_public PRIVATE ${tfpsacrypto_static_target} ${CMAKE_THREAD_LIBS_INIT})
 
 # mldsa_sign
@@ -14,6 +22,7 @@ target_include_directories(mldsa_sign PRIVATE
       ${PROJECT_SOURCE_DIR}/drivers/pqcp/mldsa-native/mldsa/
 )
 
+tfpsacrypto_mldsa_enable_dead_code_elimination(mldsa_sign)
 target_link_libraries(mldsa_sign PRIVATE ${tfpsacrypto_static_target} ${CMAKE_THREAD_LIBS_INIT})
 
 # mldsa_verify
@@ -23,4 +32,5 @@ target_include_directories(mldsa_verify PRIVATE
       ${PROJECT_SOURCE_DIR}/drivers/pqcp/mldsa-native/mldsa/
 )
 
+tfpsacrypto_mldsa_enable_dead_code_elimination(mldsa_verify)
 target_link_libraries(mldsa_verify PRIVATE ${tfpsacrypto_static_target} ${CMAKE_THREAD_LIBS_INIT})

tests/scripts/components-configuration-crypto.sh

@@ -515,6 +515,13 @@ component_test_pqcp_own_shake_no_builtin () {
     ctest
 }
 
+support_build_mldsa_program_symbol_partition () {
+    case "$OSTYPE" in
+        msys*|cygwin*|win32*) false ;;
+        *) type nm >/dev/null 2>/dev/null ;;
+    esac
+}
+
 component_build_mldsa_program_symbol_partition () {
     msg "build: ML-DSA program symbol partition"
 
@@ -524,7 +531,9 @@ component_build_mldsa_program_symbol_partition () {
 
     cd "$OUT_OF_SOURCE_DIR"
     cmake -DENABLE_PROGRAMS=ON -DENABLE_TESTING=OFF "$TF_PSA_CRYPTO_ROOT_DIR"
-    cmake --build . --target mldsa_export_public mldsa_sign mldsa_verify
+    cmake --build . --target mldsa_export_public
+    cmake --build . --target mldsa_sign
+    cmake --build . --target mldsa_verify
 
     nm -C --defined-only programs/mldsa/mldsa_sign > mldsa_sign.syms
     nm -C --defined-only programs/mldsa/mldsa_verify > mldsa_verify.syms