[test] [ir] Add a simple unit test for IRBuilder (#2214)

* [test] [ir] Add basic IR unit test

* comments

cmake/TaichiCore.cmake

@@ -74,20 +74,45 @@ if (TI_WITH_CC)
   list(APPEND TAICHI_CORE_SOURCE ${TAICHI_CC_SOURCE})
 endif()
 
-# We don't mean to create a dedicated library just for common. Instead, we are
-# trying to identify, refactor and group the core files into a smaller lib. This
-# lib should be mostly self-contained and completely Taichi focused, free from
-# the "application" layer such as pybind11 or GUI.
-file(GLOB TAICHI_TESTABLE_SRC "taichi/common/*.cpp" "taichi/common/*.h")
+# This compiles all the libraries with -fPIC, which is critical to link a static
+# library into a shared lib.
+set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+
+# The short-term goal is to have a sub-library that is mostly Taichi-focused,
+# free from the "application" layer such as pybind11 or GUI. At a minimum, we
+# must decouple from pybind11/python-environment. This sub-lib will then be
+# unit testtable.
+# TODO(#2198): Long-term speaking, we should create a separate library for each
+# sub-module. This way we can guarantee that the lib dependencies form a DAG.
+file(GLOB TAICHI_TESTABLE_SRC
+      "taichi/common/*.cpp"
+      "taichi/common/*.h"
+      "taichi/ir/ir_builder.*"
+      "taichi/ir/ir.*"
+      "taichi/ir/offloaded_task_type.*"
+      "taichi/ir/snode_types.*"
+      "taichi/ir/snode.*"
+      "taichi/ir/statements.*"
+      "taichi/ir/type_factory.*"
+      "taichi/ir/type_utils.*"
+      "taichi/ir/type.*"
+      "taichi/transforms/statement_usage_replace.cpp"
+      "taichi/program/arch.*"
+      "taichi/program/compile_config.*"
+      "taichi/system/timer.*"
+      "taichi/system/profiler.*"
+)
+
 # TODO(#2196): Maybe we can do the following renaming in the end?
 # taichi_core --> taichi_pylib (this requires python-side refactoring...)
 # taichi_testable_lib --> taichi_core
 set(TAICHI_TESTABLE_LIB taichi_testable_lib)
-add_library(${TAICHI_TESTABLE_LIB} OBJECT ${TAICHI_TESTABLE_SRC})
-set_property(TARGET ${TAICHI_TESTABLE_LIB} PROPERTY POSITION_INDEPENDENT_CODE ON)
+add_library(${TAICHI_TESTABLE_LIB} STATIC ${TAICHI_TESTABLE_SRC})
 
 list(REMOVE_ITEM TAICHI_CORE_SOURCE ${TAICHI_TESTABLE_SRC})
-add_library(${CORE_LIBRARY_NAME} SHARED ${TAICHI_CORE_SOURCE} ${PROJECT_SOURCES} $<TARGET_OBJECTS:${TAICHI_TESTABLE_LIB}>)
+
+add_library(${CORE_LIBRARY_NAME} SHARED ${TAICHI_CORE_SOURCE})
+target_link_libraries(${CORE_LIBRARY_NAME} ${TAICHI_TESTABLE_LIB})
 
 if (APPLE)
     # Ask OS X to minic Linux dynamic linking behavior

cmake/TaichiTests.cmake

@@ -15,7 +15,8 @@ include_directories(
     ${PROJECT_SOURCE_DIR},
 )
 
-add_executable(${TESTS_NAME} ${TAICHI_TESTS_SOURCE} $<TARGET_OBJECTS:taichi_testable_lib>)
+add_executable(${TESTS_NAME} ${TAICHI_TESTS_SOURCE})
+target_link_libraries(${TESTS_NAME} taichi_testable_lib)
 target_link_libraries(${TESTS_NAME} gtest_main)
 
 add_test(NAME ${TESTS_NAME} COMMAND ${TESTS_NAME})

tests/cpp_new/ir/ir_builder_test.cpp

@@ -0,0 +1,22 @@
+#include "gtest/gtest.h"
+
+#include "taichi/ir/ir_builder.h"
+#include "taichi/ir/statements.h"
+
+namespace taichi {
+namespace lang {
+
+TEST(IRBuilder, Basic) {
+  IRBuilder builder;
+  auto *lhs = builder.get_int32(40);
+  auto *rhs = builder.get_int32(2);
+  auto *add = builder.create_add(lhs, rhs);
+  ASSERT_TRUE(add->is<BinaryOpStmt>());
+  auto *addc = add->cast<BinaryOpStmt>();
+  EXPECT_EQ(addc->lhs, lhs);
+  EXPECT_EQ(addc->rhs, rhs);
+  EXPECT_EQ(addc->op_type, BinaryOpType::add);
+}
+
+}  // namespace lang
+}  // namespace taichi