Add minimal code to compile LF for FlexPRET with uC reactor. Does not…

… print the expected "hello world"

core/src/main/java/org/lflang/target/Target.java

@@ -608,7 +608,8 @@ public void initialize(TargetConfig config) {
               WorkersProperty.INSTANCE);
     case UC ->
         config.register(
-            BuildTypeProperty.INSTANCE);
+            BuildTypeProperty.INSTANCE,
+            PlatformProperty.INSTANCE);
       case CPP ->
           config.register(
               BuildTypeProperty.INSTANCE,

core/src/main/kotlin/org/lflang/generator/uc/UcCmakeGenerator.kt

@@ -6,6 +6,7 @@ import org.lflang.target.TargetConfig
 import org.lflang.generator.PrependOperator
 import org.lflang.joinWithLn
 import org.lflang.target.property.BuildTypeProperty
+import org.lflang.target.property.PlatformProperty
 import org.lflang.target.property.CmakeIncludeProperty
 import org.lflang.target.property.ExternalRuntimePathProperty
 import org.lflang.target.property.RuntimeVersionProperty
@@ -14,22 +15,36 @@ import java.nio.file.Path
 
 class UcCmakeGenerator(private val targetConfig: TargetConfig, private val fileConfig: FileConfig) {
     private val S = '$' // a little trick to escape the dollar sign with $S
+    // FIXME: I literally don't know how to uppercase a string in Kotlin...
+    private val platformName = targetConfig.get(PlatformProperty.INSTANCE).platform
     fun generateCmake(sources: List<Path>) = with(PrependOperator) {
         """
             |cmake_minimum_required(VERSION 3.5)
+            |set(PLATFORM "FLEXPRET" CACHE STRING "Platform to target")
+            |
+            |if ($S{PLATFORM} STREQUAL "FLEXPRET")
+            |   # Must include toolchain file before project(), otherwise cmake
+            |   # will determine its own compiler settings
+            |   include(${S}ENV{FP_SDK_PATH}/cmake/riscv-toolchain.cmake)
+            |endif()
+            |
             |project(${fileConfig.name} VERSION 0.0.0 LANGUAGES C)
-            |set(PLATFORM "POSIX" CACHE STRING "Platform to target")
             |
             |set(LF_MAIN_TARGET ${fileConfig.name})
             |set(SOURCES
         ${" |    "..sources.joinWithLn { it.toUnixString() }}
             |)
-            |if (PLATFORM STREQUAL "POSIX")
+            |if ($S{PLATFORM} STREQUAL "POSIX")
             |   add_library($S{LF_MAIN_TARGET} STATIC $S{SOURCES})
-            |elseif (PLATFORM STREQUAL "ZEPHYR")
+            |elseif ($S{PLATFORM} STREQUAL "ZEPHYR")
             |   zephyr_library_named($S{LF_MAIN_TARGET})
             |   zephyr_library_sources($S{SOURCES})
             |   zephyr_library_link_libraries(kernel)
+            |elseif ($S{PLATFORM} STREQUAL "FLEXPRET")
+            |   add_library($S{LF_MAIN_TARGET} STATIC $S{SOURCES})
+            |   # Include FlexPRET's SDK functionality
+            |   include(${S}ENV{FP_SDK_PATH}/cmake/fp-app.cmake)
+            |   add_subdirectory(${S}ENV{FP_SDK_PATH} BINARY_DIR)
             |else()
             |   message(FATAL_ERROR "PLATFORM not defined")
             |endif()

core/src/main/kotlin/org/lflang/generator/uc/UcReactorGenerator.kt

@@ -91,11 +91,12 @@ class UcReactorGenerator(private val reactor: Reactor, fileConfig: UcFileConfig,
         """.trimMargin()
     }
 
+    // FIXME: 3rd argument must be replaced with self->parent if not main reactor
     fun generateCtorDefinition() = with(PrependOperator) {
         """
             | void ${reactor.name}_ctor(${reactor.name} *self, Environment *env) {
             |  size_t trigger_idx = 0;
-            |  Reactor_ctor(&self->super, "${reactor.name}", env, ${if (numChildren > 0) "self->_children" else "NULL"}, $numChildren, ${if (reactor.reactions.size > 0) "self->_reactions" else "NULL"}, ${reactor.reactions.size}, ${if (numTriggers() > 0) "self->_triggers" else "NULL"}, ${numTriggers()});
+            |  Reactor_ctor(&self->super, "${reactor.name}", env, NULL, ${if (numChildren > 0) "self->_children" else "NULL"}, $numChildren, ${if (reactor.reactions.size > 0) "self->_reactions" else "NULL"}, ${reactor.reactions.size}, ${if (numTriggers() > 0) "self->_triggers" else "NULL"}, ${numTriggers()});
         ${" |  "..timers.generateReactorCtorCodes()}
         ${" |  "..reactions.generateReactorCtorCodes()}
             | }

test/uC/main/CMakeLists.txt

@@ -0,0 +1,26 @@
+cmake_minimum_required(VERSION 3.22)
+
+# Set toolchain to RISC-V; must be done before call to project()
+include($ENV{FP_SDK_PATH}/cmake/riscv-toolchain.cmake)
+
+project(lf-fp-uc
+  LANGUAGES C
+  DESCRIPTION "LF on FlexPRET using uC runtime"
+  VERSION 1.0.0
+)
+
+add_executable(fp-lf-uc main.c)
+
+target_link_libraries(fp-lf-uc PRIVATE
+    ${CMAKE_CURRENT_LIST_DIR}/../build/libFlexPRET_uC.a
+    ${CMAKE_CURRENT_LIST_DIR}/../build/reactor-uc/libreactor-uc.a
+)
+
+set(DEBUG true)
+
+add_subdirectory($ENV{FP_SDK_PATH} BINARY_DIR)
+target_link_libraries(fp-lf-uc PRIVATE fp-sdk)
+
+include($ENV{FP_SDK_PATH}/cmake/fp-app.cmake)
+
+fp_add_outputs(fp-lf-uc)

test/uC/main/main.c

@@ -0,0 +1,4 @@
+#include "../src-gen/lf_main.h"
+int main(void) {
+    lf_main(0, 0);
+}

test/uC/src/FlexPRET_uC.lf

@@ -0,0 +1,10 @@
+target uC {
+    platform: "FlexPRET"
+}
+
+main reactor {
+    timer t(0, 100 msec)
+    reaction(t) {=
+      printf("Hello World from FlexPRET!\n");
+     =}
+}