[sledge] Improve build of model/cxxabi.bc

Summary:
Make could get confused and use both the $(MODEL_DIR)/cxxabi.bc and
%.bc rules, leading to build failure.

Reviewed By: jvillard

Differential Revision: D14385600

fbshipit-source-id: 05f0ac6e1

sledge/model/Makefile

@@ -0,0 +1,27 @@
+# Copyright (c) 2019-present, Facebook, Inc.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+# additional arguments to pass to clang
+OPT_ARGS?=-Os
+CLANG_ARGS?=-g $(OPT_ARGS)
+
+# select llvm and clang
+SWITCH?=$(shell opam switch show)
+LLVM?=../llvm/_install/$(SWITCH)
+
+LIBCXXABI=../llvm/projects/libcxxabi
+
+cxxabi.bc : cxxabi.cpp
+	$(LLVM)/bin/clang $(CLANG_ARGS) -I$(LLVM)/include/c++/v1 -I$(LIBCXXABI)/include -I$(LIBCXXABI)/src -c -emit-llvm cxxabi.cpp
+
+clean:
+	rm cxxabi.bc
+
+fmt:
+	clang-format -i *.h *.c *.cpp
+
+# print any variable for Makefile debugging
+print-%:
+	@printf '$*='; printf '$($*)'; printf '\n'

sledge/model/cxxabi.cpp

@@ -5,9 +5,6 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-/* A simple implementation of the Itanium Base ABI for analysis purposes.
-   See http://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html */
-
 #include "abort_message.cpp"
 #include "cxa_exception.cpp"
 #include "cxa_exception_storage.cpp"

sledge/model/llair_intrinsics.h

@@ -5,7 +5,14 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+#include <stdlib.h>
+
+#ifdef __cplusplus
 extern "C" {
+#endif
 
 __attribute__((noreturn)) void __llair_throw(void* thrown_exception);
+
+#ifdef __cplusplus
 }
+#endif

sledge/test/Makefile

@@ -38,19 +38,21 @@ Outs:=$(patsubst %.bc,%.bc.out,$(TestBCs)) $(patsubst %.ll,%.ll.out,$(TestLLs))
 
 default: test
 
-$(MODEL_DIR)/cxxabi.bc: $(MODEL_DIR)/cxxabi.cpp
+$(MODEL_DIR)/cxxabi.bc : $(MODEL_DIR)/cxxabi.cpp
-	@(cd $(MODEL_DIR) && clang $(CLANG_ARGS) -I../llvm/projects/libcxxabi/include -I../llvm/projects/libcxxabi/src -c -emit-llvm cxxabi.cpp)
+	@(cd $(dir $@) && clang $(CLANG_ARGS) -I../llvm/projects/libcxxabi/include -I../llvm/projects/libcxxabi/src -c -emit-llvm cxxabi.cpp)
 
 # compile c to llvm bitcode
 %.bc : %.c $(MODEL_DIR)/cxxabi.bc
 	@(cd $(dir $*) && clang $(CLANG_ARGS) -c -emit-llvm $(notdir $*).c -o - | opt $(OPT_ARGS) -o $(notdir $*).bc)
 
+#  $(MODEL_DIR)/cxxabi.bc
 #	@(cd $(dir $*) && clang $(CLANG_ARGS) -c -emit-llvm $(notdir $*).c -o - | llvm-link $(MODEL_DIR)/cxxabi.bc - | opt $(OPT_ARGS) -o $(notdir $*).bc)
 
 # compile c++ to llvm bitcode
-%.bc : %.cpp $(MODEL_DIR)/cxxabi.bc
+%.bc : %.cpp
 	@(cd $(dir $*) && clang $(CLANG_ARGS) -c -emit-llvm $(notdir $*).cpp -o - | opt $(OPT_ARGS) -o $(notdir $*).bc)
 
+#  $(MODEL_DIR)/cxxabi.bc
 #	@(cd $(dir $*) && clang $(CLANG_ARGS) -c -emit-llvm $(notdir $*).cpp -o - | llvm-link $(MODEL_DIR)/cxxabi.bc - | opt $(OPT_ARGS) -o $(notdir $*).bc)
 
 # disassemble bitcode to llvm assembly