llc only supports one input file

cmake/LLVMIRUtil.cmake

@@ -753,14 +753,26 @@ function(llvmir_attach_obj_target)
     list(APPEND IN_FULL_LLVMIR_FILES "${IN_LLVMIR_DIR}/${IN_LLVMIR_FILE}")
   endforeach()
 
-  set(FULL_OUT_LLVMIR_FILE "${WORK_DIR}/${TRGT}.o")
-  if(SHORT_NAME)
-    set(FULL_OUT_LLVMIR_FILE "${WORK_DIR}/${SHORT_NAME}.o")
-  endif()
-  get_filename_component(OUT_LLVMIR_FILE ${FULL_OUT_LLVMIR_FILE} NAME)
+  foreach(IN_LLVMIR_FILE ${IN_FULL_LLVMIR_FILES})
+    get_filename_component(OUTFILE ${IN_LLVMIR_FILE} NAME_WE)
+    set(OUT_LLVMIR_FILE "${OUTFILE}.o")
+    set(FULL_OUT_LLVMIR_FILE "${WORK_DIR}/${OUT_LLVMIR_FILE}")
 
-  list(APPEND OUT_LLVMIR_FILES ${OUT_LLVMIR_FILE})
-  list(APPEND FULL_OUT_LLVMIR_FILES ${FULL_OUT_LLVMIR_FILE})
+    add_custom_command(OUTPUT ${FULL_OUT_LLVMIR_FILE}
+        COMMAND llc
+        ARGS
+          -filetype=obj
+          -relocation-model=pic
+          -o=${FULL_OUT_LLVMIR_FILE}
+          ${LLVMIR_ATTACH_UNPARSED_ARGUMENTS}
+          ${IN_LLVMIR_FILE}
+        DEPENDS ${IN_LLVMIR_FILE}
+        COMMENT "Generating object ${OUT_LLVMIR_FILE}"
+        VERBATIM)
+
+    list(APPEND OUT_LLVMIR_FILES ${OUT_LLVMIR_FILE})
+    list(APPEND FULL_OUT_LLVMIR_FILES ${FULL_OUT_LLVMIR_FILE})
+  endforeach()
 
   # setup custom target
   add_custom_target(${TRGT} DEPENDS ${FULL_OUT_LLVMIR_FILES})
@@ -786,16 +798,6 @@ function(llvmir_attach_obj_target)
   set_property(TARGET ${TRGT} PROPERTY EXCLUDE_FROM_ALL On)
   set_property(TARGET ${TRGT} PROPERTY LLVMIR_SHORT_NAME ${SHORT_NAME})
 
-  add_custom_command(OUTPUT ${FULL_OUT_LLVMIR_FILE}
-    COMMAND llc
-    ARGS
-    -filetype=obj
-    ${LLVMIR_ATTACH_UNPARSED_ARGUMENTS}
-    -o ${FULL_OUT_LLVMIR_FILE} ${IN_FULL_LLVMIR_FILES}
-    DEPENDS ${IN_FULL_LLVMIR_FILES}
-    COMMENT "Generating object ${OUT_LLVMIR_FILE}"
-    VERBATIM)
-
   ## postamble
 endfunction()
 

example04/CMakeLists.txt

@@ -0,0 +1,17 @@
+# cmake file
+
+cmake_minimum_required(VERSION 3.9)
+
+find_program(CMAKE_C_COMPILER clang)
+find_program(CMAKE_CXX_COMPILER clang++)
+
+project(staticlib)
+
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/../cmake")
+
+message(STATUS ${CMAKE_MODULE_PATH})
+include(LLVMIRUtil)
+
+add_subdirectory(staticlib)
+add_subdirectory(executable)
+

example04/README.txt

@@ -0,0 +1,9 @@
+# Instrumenting an static library
+
+```sh
+mkdir build && cd build
+cmake ..
+make testlib_instrumented
+make main
+./executable/main
+```

example04/executable/CMakeLists.txt

@@ -0,0 +1,3 @@
+add_executable(main main.c)
+target_include_directories(main PUBLIC "./../staticlib/include")
+target_link_libraries(main "${CMAKE_BINARY_DIR}/staticlib/libtestlib_instrumented.a")

example04/executable/main.c

@@ -0,0 +1,8 @@
+#include "Test1.h"
+
+int main(int argc, char **argv)
+{
+  puts("Calling Test1 from static lib!");
+  Test1();
+  return 0;
+}

example04/staticlib/CMakeLists.txt

@@ -0,0 +1,18 @@
+set(CMAKE_BUILD_TYPE Debug)
+# set(LLVM_PASS_PLUGIN "<filepath to llvm plugin pass>")
+
+set(SOURCE_FILES
+  src/Test1.c
+  src/Test2.c
+  src/Test3.c
+)
+
+add_library(testlib STATIC ${SOURCE_FILES})
+target_include_directories(testlib PUBLIC "./include")
+set_target_properties(testlib PROPERTIES LINKER_LANGUAGE C)
+
+llvmir_attach_bc_target(testlib_bc testlib)
+llvmir_attach_opt_pass_target(testlib_opt testlib_bc) # -load-pass-plugin=${LLVM_PASS_PLUGIN} -passes=ctrace)
+
+llvmir_attach_obj_target(testlib_obj testlib_opt)
+llvmir_attach_library(testlib_instrumented testlib_obj STATIC)

example04/staticlib/include/Test1.h

@@ -0,0 +1,4 @@
+#include <stdlib.h>
+#include "Test2.h"
+
+void Test1();

example04/staticlib/include/Test2.h

@@ -0,0 +1,4 @@
+#include "Test3.h"
+#include <stdio.h>
+
+void Test2();

example04/staticlib/include/Test3.h

@@ -0,0 +1,3 @@
+#include <stdio.h>
+
+void Test3();

example04/staticlib/src/Test1.c

@@ -0,0 +1,7 @@
+#include "Test1.h"
+
+void Test1()
+{
+  puts("Test1 called");
+  Test2();
+}

example04/staticlib/src/Test2.c

@@ -0,0 +1,7 @@
+#include "Test2.h"
+
+void Test2()
+{
+  puts("Test2 called!");
+  Test3();
+}

example04/staticlib/src/Test3.c

@@ -0,0 +1,6 @@
+#include "Test3.h"
+
+void Test3()
+{
+  puts("Test3 called");
+}