llvm-project/llvm/test/Transforms/DeadArgElim/deadretval2.ll

60 lines
1.5 KiB
LLVM

; RUN: opt < %s -deadargelim -die -S > %t
; RUN: cat %t | not grep DEAD
; RUN: cat %t | grep LIVE | count 4
@P = external global i32 ; <i32*> [#uses=1]
; Dead arg only used by dead retval
define internal i32 @test(i32 %DEADARG) {
ret i32 %DEADARG
}
define internal i32 @test2(i32 %DEADARG) {
%DEADRETVAL = call i32 @test( i32 %DEADARG ) ; <i32> [#uses=1]
ret i32 %DEADRETVAL
}
define void @test3(i32 %X) {
%DEADRETVAL = call i32 @test2( i32 %X ) ; <i32> [#uses=0]
ret void
}
define internal i32 @foo() {
%DEAD = load i32, i32* @P ; <i32> [#uses=1]
ret i32 %DEAD
}
define internal i32 @id(i32 %X) {
ret i32 %X
}
define void @test4() {
%DEAD = call i32 @foo( ) ; <i32> [#uses=1]
%DEAD2 = call i32 @id( i32 %DEAD ) ; <i32> [#uses=0]
ret void
}
; These test if returning another functions return value properly marks that
; other function's return value as live. We do this twice, with the functions in
; different orders (ie, first the caller, than the callee and first the callee
; and then the caller) since DAE processes functions one by one and handles
; these cases slightly different.
define internal i32 @test5() {
ret i32 123
}
define i32 @test6() {
%LIVE = call i32 @test5()
ret i32 %LIVE
}
define i32 @test7() {
%LIVE = call i32 @test8()
ret i32 %LIVE
}
define internal i32 @test8() {
ret i32 124
}