1，clang query 概述

作用：
檢查一個(gè)程序源碼的抽象語法樹，測試 AST 匹配器；
幫助檢查哪些 AST 節(jié)點(diǎn)與指定的 AST 匹配器相匹配；

2，clang-query 安裝

準(zhǔn)備：

git clone --recursive https://github.com/llvm/llvm-project.git
cd llvm-project/
git checkout  llvmorg-3.5.0
cp -r ./clang ./llvm/tools/
cp -r clang-tools-extra ./llvm/tools/clang/tools/extra
mkdir build_d ../local_d
cd build_d #其絕對(duì)路徑為：/home/hipper/llvm_3_4_0_ex/browse/local_d，如下配置所用

配置：

cmake -G "Unix Makefiles"            \
-DCLANG_ENABLE_STATIC_ANALYZER=1     \
-DLLVM_ENABLE_ASSERTIONS=On          \
-DCMAKE_BUILD_TYPE=Debug             \
-DCMAKE_INSTALL_PREFIX=/home/hipper/llvm_3_4_0_ex/browse/local_d   \
-DLLVM_ENABLE_LIBCXX=1               \
-DLLVM_ENABLE_PROJECTS="all"         \../llvm

編譯安裝：

make -j34
make install
cp bin/clang-query /home/hipper/llvm_3_4_0_ex/browse/local_d/bin/

3，測試運(yùn)行

待測試程序源代碼：
hello.c
?

hello.cextern int write(int, const char*, unsigned long);int main(){write(1, "Hello, ", 7);write(1, "world", 5);write(1, "!\n", 2);return 0;}

測試：
?

$ clang-query hello.c --

效果：

識(shí)別出函數(shù)調(diào)用表達(dá)式，并打印出來了

4, 更多測試

wildanimal-sim.cpp

class Plane{public:int run(int x)
{return 10*x;
}};class Animal {
public:int position;
public:Animal(int pos) : position(pos) {}// Return new positionint run(int quantity) {return position += quantity;}
};
class Cat : public Animal {
public:Cat(int pos) : Animal(pos) {}void meow() {}void destroySofa() {}bool wildMood() {return true;}int run(int quantity){return position += 2*quantity;}
};
int main() {Cat c(50); c.meow();if (c.wildMood())c.destroySofa();c.run(2);Plane pp;pp.run(3);return 0;
}

可以直接輸出 AST 的clang 命令：

clang -Xclang -ast-dump hello.c
clang -cc1 -ast-dump hello.c

clang-query? wildanimal-sim.cpp

測試如下命令：

?

clang-query> set output dump
clang-query> match recordDecl()
clang-query> match methodDecl(hasName("run"))
clang-query> match     recordDecl(isSameOrDerivedFrom(hasName("Animal")))
clang-query> match     recordDecl(allOf(hasMethod(methodDecl(hasName("run"))),   isSameOrDerivedFrom(hasName("Animal"))))

LLVM-18:
?

clang-query> match cxxMemberCallExpr()
clang-query> match cxxMemberCallExpr(callee(memberExpr(member(hasName("run")))))
# not work。 clang-query> match cxxMemberCallExpr(callee(memberExpr(member(hasName("run")))), thisPointerType(recordDecl(isSameOrDerivedFrom(hasName("Animal")))))

LLVM-3.5
?

clang-query> match memberCallExpr()
clang-query> match memberCallExpr(callee(memberExpr(member(hasName("run")))))
clang-query> match memberCallExpr(callee(memberExpr(member(hasName("run")))), thisPointerType(recordDecl(isSameOrDerivedFrom(hasName("Animal")))))

效果