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; RUN: opt < %s -passes=deadargelim -S | FileCheck %s
%Ty = type { i32, i32 }
; Validate that the argument and return value are both dead
; CHECK-LABEL: define internal void @test1()
define internal ptr @test1(ptr %this) {
ret ptr %this
}
; do not keep alive the return value of a function with a dead 'returned' argument
; CHECK-LABEL: define internal void @test2()
define internal ptr @test2(ptr returned %this) {
ret ptr %this
}
; dummy to keep 'this' alive
@dummy = global ptr null
; Validate that return value is dead
; CHECK-LABEL: define internal void @test3(ptr %this)
define internal ptr @test3(ptr %this) {
store volatile ptr %this, ptr @dummy
ret ptr %this
}
; keep alive return value of a function if the 'returned' argument is live
; CHECK-LABEL: define internal ptr @test4(ptr returned %this)
define internal ptr @test4(ptr returned %this) {
store volatile ptr %this, ptr @dummy
ret ptr %this
}
; don't do this if 'returned' is on the call site...
; CHECK-LABEL: define internal void @test5(ptr %this)
define internal ptr @test5(ptr %this) {
store volatile ptr %this, ptr @dummy
ret ptr %this
}
; Drop all these attributes
; CHECK-LABEL: define internal void @test6
define internal align 8 dereferenceable_or_null(2) noundef noalias ptr @test6() {
ret ptr null
}
define ptr @caller(ptr %this) {
%1 = call ptr @test1(ptr %this)
%2 = call ptr @test2(ptr %this)
%3 = call ptr @test3(ptr %this)
%4 = call ptr @test4(ptr %this)
; ...instead, drop 'returned' form the call site
; CHECK: call void @test5(ptr %this)
%5 = call ptr @test5(ptr returned %this)
%6 = call ptr @test6()
ret ptr %this
}
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