【发布时间】：2022-08-21 13:26:01
【问题描述】：
我尝试像示例代码一样调用我的函数：
use std::arch::asm;
extern \"C\" fn foo(arg: i32) -> i32 {
println!(\"arg = {}\", arg);
arg * 2
}
fn call_foo(arg: i32) -> i32 {
unsafe {
let result;
asm!(
\"call *{}\",
// Function pointer to call
in(reg) foo,
// 1st argument in rdi
in(\"rdi\") arg,
// Return value in rax
out(\"rax\") result,
// Mark all registers which are not preserved by the \"C\" calling
// convention as clobbered.
clobber_abi(\"C\"),
);
result
}
} //this is the example code
我的代码：
use core::arch::global_asm;
fn main() {
println!(\"Hello, world!\");
unsafe{
myfunc();
}
}
fn pt() {
println!(\"This func is called by inline asm\");
}
extern \"C\" {
fn myfunc();
}
global_asm!(
\"
.global myfunc
myfunc:
call *{}
ret\",
in(reg) pt,
);
它在编译时引发错误
Compiling asm_test v0.1.0 (/home/zhou/codes/rust/practice/asm_test)
error: expected expression, found keyword `in`
--> src/main.rs:26:1
|
26 | in(reg) pt,
| ^^ expected expression
error: could not compile `asm_test` due to previous error
如果我尝试只是call pt，就像这样
use core::arch::global_asm;
fn main() {
println!(\"Hello, world!\");
unsafe{
myfunc();
}
}
fn pt() {
println!(\"This func is called by inline asm\");
}
extern \"C\" {
fn myfunc();
}
global_asm!(
\"
.global myfunc
myfunc:
call pt
ret\",
);
它引发了链接时错误：
error: linking with `cc` failed: exit status: 1
|
= note: \"cc\" \"-m64\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.0.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.1.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.2.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.3.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.4.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.5.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.6.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.7.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.4utlkaaskc2kqzwc.rcgu.o\" \"-Wl,--as-needed\" \"-L\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps\" \"-L\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib\" \"-Wl,--start-group\" \"-Wl,-Bstatic\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-a46a068050a12a4b.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-1df56095db9453cb.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libminiz_oxide-9062de483386e50b.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libadler-b988ab269ff13602.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libobject-1bc822d886d4f7bd.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libmemchr-963eca8df4c224a6.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libaddr2line-d805b480c9102e58.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libgimli-06dfdbc22b935051.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd_detect-d7523a4d118e6572.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-5d7898c7fac3a07d.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-8c2bdbab4845bf3d.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-d578639df0547b30.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-58bbb7b1efa3a5e2.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcfg_if-4c9b082d197c16f8.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-70f9ed6d8e7a5ce6.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-8c0a241d0360fa53.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-bad7ed93fdd31371.rlib\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-98b4d121af2b7335.rlib\" \"-Wl,--end-group\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-1d9f7e5920635d15.rlib\" \"-Wl,-Bdynamic\" \"-lgcc_s\" \"-lutil\" \"-lrt\" \"-lpthread\" \"-lm\" \"-ldl\" \"-lc\" \"-Wl,--eh-frame-hdr\" \"-Wl,-znoexecstack\" \"-L\" \"/home/zhou/.rustup/toolchains/1.59.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib\" \"-o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301\" \"-Wl,--gc-sections\" \"-pie\" \"-Wl,-zrelro,-znow\" \"-nodefaultlibs\"
= note: /usr/bin/ld: /home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-cefff555edfd8301.asm_test.debf28cc-cgu.6.rcgu.o: in function `myfunc\':
asm_test.debf28cc-cgu.6:(.text+0x1): undefined reference to `pt\'
collect2: error: ld returned 1 exit status
= help: some `extern` functions couldn\'t be found; some native libraries may need to be installed or have their path specified
= note: use the `-l` flag to specify native libraries to link
= note: use the `cargo:rustc-link-lib` directive to specify the native libraries to link with Cargo (see https://doc.rust-lang.org/cargo/reference/build-scripts.html#cargorustc-link-libkindname)
warning: `asm_test` (bin \"asm_test\") generated 1 warning
error: could not compile `asm_test` due to previous error; 1 warning emitted
我的 rustc 版本是rustc 1.59.0 (9d1b2106e 2022-02-23)
现在我想知道如何在内联 asm 中调用我的 rust 函数？ 谢谢回答。
ps：
即使我将extern \"C\" 标记为pt() 函数，它也会引发同样的错误。
通过函数指针调用：
use core::arch::global_asm;
fn main() {
println!(\"Hello, world!\");
unsafe{
myfunc();
}
}
extern \"C\" fn pt() {
println!(\"This func is called by inline asm\");
}
extern \"C\" {
fn myfunc();
}
global_asm!(
\"
.global myfunc
myfunc:
call *{}
ret\",
in(reg) pt,
);
输出：
Compiling asm_test v0.1.0 (/home/zhou/codes/rust/practice/asm_test)
error: expected expression, found keyword `in`
--> src/main.rs:25:1
|
25 | in(reg) pt,
| ^^ expected expression
error: could not compile `asm_test` due to previous error
通过函数名直接调用：
use core::arch::global_asm;
fn main() {
println!(\"Hello, world!\");
unsafe{
myfunc();
}
}
extern \"C\" fn pt() {
println!(\"This func is called by inline asm\");
}
extern \"C\" {
fn myfunc();
}
global_asm!(
\"
.global myfunc
myfunc:
call pt
ret
\"
);
输出
Compiling asm_test v0.1.0 (/home/zhou/codes/rust/practice/asm_test)
warning: function is never used: `pt`
--> src/main.rs:11:15
|
11 | extern \"C\" fn pt() {
| ^^
|
= note: `#[warn(dead_code)]` on by default
error: linking with `cc` failed: exit status: 1
|
= note: \"cc\" \"-m64\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.11cntnpkwkcxlijf.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.1265vrgnblsvk7p4.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.1t6teuukd293c2fa.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.2dq4ncsizye722cr.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.3wcrpa0pe60imxoq.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.472oc353m17m7nk9.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.4jq8ds1i0f9k3y80.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.qpnijj966uqfsk9.rcgu.o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.4jqwi4eladczupq3.rcgu.o\" \"-Wl,--as-needed\" \"-L\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps\" \"-L\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib\" \"-Wl,--start-group\" \"-Wl,-Bstatic\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-8d61b92a0a02f53a.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-fc45202bb435016b.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libminiz_oxide-f2400674c7513725.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libadler-605c3a7d1a5d300d.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libobject-3d4fb4efa907e4e8.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libmemchr-65207f030ab23308.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libaddr2line-76ca199cb0186109.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libgimli-1e3e01ed4f561dc1.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-dd8dddcba7c13fee.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd_detect-00b13d31c3420656.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-e4c8460b81557bd5.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-600d46e5f0005455.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-e4a08a2585b62d37.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcfg_if-fbc21ec567cb9dc7.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-10b3fa8e49bd978f.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-64625b73694ffce7.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-fb6b78ac543a58ee.rlib\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-1d1f2d1bec6f51b8.rlib\" \"-Wl,--end-group\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-acf5ff6e9595d982.rlib\" \"-Wl,-Bdynamic\" \"-lgcc_s\" \"-lutil\" \"-lrt\" \"-lpthread\" \"-lm\" \"-ldl\" \"-lc\" \"-Wl,--eh-frame-hdr\" \"-Wl,-znoexecstack\" \"-L\" \"/home/zhou/.rustup/toolchains/1.60.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib\" \"-o\" \"/home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c\" \"-Wl,--gc-sections\" \"-pie\" \"-Wl,-zrelro,-znow\" \"-nodefaultlibs\"
= note: /usr/bin/ld: /home/zhou/codes/rust/practice/asm_test/target/debug/deps/asm_test-0ec3f71f4270eb6c.2dq4ncsizye722cr.rcgu.o: in function `myfunc\':
2dq4ncsizye722cr:(.text+0x1): undefined reference to `pt\'
collect2: error: ld returned 1 exit status
= help: some `extern` functions couldn\'t be found; some native libraries may need to be installed or have their path specified
= note: use the `-l` flag to specify native libraries to link
= note: use the `cargo:rustc-link-lib` directive to specify the native libraries to link with Cargo (see https://doc.rust-lang.org/cargo/reference/build-scripts.html#cargorustc-link-libkindname)
warning: `asm_test` (bin \"asm_test\") generated 1 warning
error: could not compile `asm_test` due to previous error; 1 warning emitted
-
在您的代码中，您不会将
pt用作extern \"C\"，因此它的名称将被破坏并且它可能会采用不同的调用约定。 -
@PitaJ 我不认为这个问题是由于缺少
extern \"C\"符号引起的。即使我添加了这个符号，编译器或链接器也会引发同样的错误。 -
也许你有this 的问题？
-
您还需要
#[no_mangle]。 -
@ChayimFriedman 非常感谢，代码可以用
#[no_mangle]成功编译
标签： assembly rust inline-assembly