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; Copyright 2013 The Rust Project Developers. See the COPYRIGHT
; file at the top-level directory of this distribution and at
; http://rust-lang.org/COPYRIGHT.
;
; Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
; http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
; <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
; option. This file may not be copied, modified, or distributed
; except according to those terms.
; Rust's try-catch
; When f(...) returns normally, the return value is null.
; When f(...) throws, the return value is a pointer to the caught exception object.
; See also: librustrt/unwind.rs
define i8* @rust_try(void (i8*,i8*)* %f, i8* %fptr, i8* %env) {
%1 = invoke i8* @rust_try_inner(void (i8*,i8*)* %f, i8* %fptr, i8* %env)
to label %normal
unwind label %catch
normal:
ret i8* %1
catch:
landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @rust_eh_personality_catch to i8*)
catch i8* null
; rust_try_inner's landing pad does not resume unwinds, so execution will never reach here
ret i8* null
}
define internal i8* @rust_try_inner(void (i8*,i8*)* %f, i8* %fptr, i8* %env) {
invoke void %f(i8* %fptr, i8* %env)
to label %normal
unwind label %catch
normal:
ret i8* null
catch:
%1 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @rust_eh_personality to i8*)
catch i8* null
; extract and return pointer to the exception object
%2 = extractvalue { i8*, i32 } %1, 0
ret i8* %2
}
declare i32 @rust_eh_personality(...)
declare i32 @rust_eh_personality_catch(...)
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