1d4e04f7a7
On Wasm, it's not currently possibly to change which `personality` is attached to a given IR function. This is primarily because no matter what `personality` is attached, codegen creates a call to a `Unwind_CallPersonality` wrapper hard-coded to call c++abi's personality. In order to allow alternative personalities without introducing bloat at each personality call site, this PR adjusts the ABI of the personality on Wasm. `Unwind_CallPersonality` is moved to `libcxxabi` under the name `__gxx_wasm_personality_v0`, with the "real" personality code renamed `__gxx_personality_imp` and called by `__gxx_wasm_personality_v0` (after resetting the landing pad context). The signature of EH personalities on Wasm is now `int personality(void* exception_object)` (where the int return is `_Unwind_Reason_Code` and the `void*` is `_Unwind_Exception*`), and personalities are expected to `__wasm_lpad_context.selector = 0;`. Based on #175202
27 lines
907 B
C
27 lines
907 B
C
//===----------------------------------------------------------------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef __WASM_UNWIND_H__
|
|
#define __WASM_UNWIND_H__
|
|
|
|
#include <threads.h>
|
|
|
|
struct _Unwind_LandingPadContext {
|
|
// Input information to personality function
|
|
uintptr_t lpad_index; // landing pad index
|
|
uintptr_t lsda; // LSDA address
|
|
|
|
// Output information computed by personality function
|
|
uintptr_t selector; // selector value
|
|
};
|
|
|
|
// Communication channel between compiler-generated user code and personality
|
|
// function
|
|
extern thread_local struct _Unwind_LandingPadContext __wasm_lpad_context;
|
|
|
|
#endif // __WASM_UNWIND_H__
|