2013-06-30 20:26:21 +00:00
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; RUN: opt < %s -deadargelim -S | FileCheck %s
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%Ty = type { i32, i32 }
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; sanity check that the argument and return value are both dead
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2013-07-12 14:54:12 +00:00
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; CHECK-LABEL: define internal void @test1()
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2013-06-30 20:26:21 +00:00
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define internal %Ty* @test1(%Ty* %this) {
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ret %Ty* %this
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}
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; do not keep alive the return value of a function with a dead 'returned' argument
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2013-07-12 14:54:12 +00:00
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; CHECK-LABEL: define internal void @test2()
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2013-06-30 20:26:21 +00:00
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define internal %Ty* @test2(%Ty* returned %this) {
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ret %Ty* %this
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}
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; dummy to keep 'this' alive
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@dummy = global %Ty* null
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; sanity check that return value is dead
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2013-07-12 14:54:12 +00:00
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; CHECK-LABEL: define internal void @test3(%Ty* %this)
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2013-06-30 20:26:21 +00:00
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define internal %Ty* @test3(%Ty* %this) {
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store volatile %Ty* %this, %Ty** @dummy
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ret %Ty* %this
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}
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; keep alive return value of a function if the 'returned' argument is live
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2013-07-12 14:54:12 +00:00
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; CHECK-LABEL: define internal %Ty* @test4(%Ty* returned %this)
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2013-06-30 20:26:21 +00:00
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define internal %Ty* @test4(%Ty* returned %this) {
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store volatile %Ty* %this, %Ty** @dummy
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ret %Ty* %this
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}
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; don't do this if 'returned' is on the call site...
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2013-07-12 14:54:12 +00:00
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; CHECK-LABEL: define internal void @test5(%Ty* %this)
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2013-06-30 20:26:21 +00:00
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define internal %Ty* @test5(%Ty* %this) {
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store volatile %Ty* %this, %Ty** @dummy
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ret %Ty* %this
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}
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define %Ty* @caller(%Ty* %this) {
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%1 = call %Ty* @test1(%Ty* %this)
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%2 = call %Ty* @test2(%Ty* %this)
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%3 = call %Ty* @test3(%Ty* %this)
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%4 = call %Ty* @test4(%Ty* %this)
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; ...instead, drop 'returned' form the call site
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; CHECK: call void @test5(%Ty* %this)
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%5 = call %Ty* @test5(%Ty* returned %this)
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ret %Ty* %this
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}
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