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; RUN: opt < %s -deadargelim -S | FileCheck %s
%Ty = type { i32, i32 }
; sanity check that the argument and return value are both dead
; CHECK: define internal void @test1()
define internal %Ty* @test1(%Ty* %this) {
ret %Ty* %this
}
; do not keep alive the return value of a function with a dead 'returned' argument
; CHECK: define internal void @test2()
define internal %Ty* @test2(%Ty* returned %this) {
ret %Ty* %this
}
; dummy to keep 'this' alive
@dummy = global %Ty* null
; sanity check that return value is dead
; CHECK: define internal void @test3(%Ty* %this)
define internal %Ty* @test3(%Ty* %this) {
store volatile %Ty* %this, %Ty** @dummy
ret %Ty* %this
}
; keep alive return value of a function if the 'returned' argument is live
; CHECK: define internal %Ty* @test4(%Ty* returned %this)
define internal %Ty* @test4(%Ty* returned %this) {
store volatile %Ty* %this, %Ty** @dummy
ret %Ty* %this
}
; don't do this if 'returned' is on the call site...
; CHECK: define internal void @test5(%Ty* %this)
define internal %Ty* @test5(%Ty* %this) {
store volatile %Ty* %this, %Ty** @dummy
ret %Ty* %this
}
define %Ty* @caller(%Ty* %this) {
%1 = call %Ty* @test1(%Ty* %this)
%2 = call %Ty* @test2(%Ty* %this)
%3 = call %Ty* @test3(%Ty* %this)
%4 = call %Ty* @test4(%Ty* %this)
; ...instead, drop 'returned' form the call site
; CHECK: call void @test5(%Ty* %this)
%5 = call %Ty* @test5(%Ty* returned %this)
ret %Ty* %this
}
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