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Never inline naked functions
The `#[naked]` attribute disabled prologue / epilogue emission for the function and it is responsibility of a developer to provide them. The compiler is no position to inline such functions correctly. Disable inlining of naked functions at LLVM and MIR level.
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// Checks that naked functions are never inlined. | ||
// compile-flags: -O -Zmir-opt-level=2 | ||
// ignore-wasm32 | ||
#![crate_type = "lib"] | ||
#![feature(asm)] | ||
#![feature(naked_functions)] | ||
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#[inline(always)] | ||
#[naked] | ||
#[no_mangle] | ||
pub unsafe extern "C" fn f() { | ||
// Check that f has naked and noinline attributes. | ||
// | ||
// CHECK: define void @f() unnamed_addr [[ATTR:#[0-9]+]] | ||
// CHECK-NEXT: start: | ||
// CHECK-NEXT: call void asm | ||
asm!("", options(noreturn)); | ||
} | ||
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#[no_mangle] | ||
pub unsafe fn g() { | ||
// Check that call to f is not inlined. | ||
// | ||
// CHECK-LABEL: define void @g() | ||
// CHECK-NEXT: start: | ||
// CHECK-NEXT: call void @f() | ||
f(); | ||
} | ||
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// CHECK: attributes [[ATTR]] = { naked noinline{{.*}} } |