2003-10-05-DeadPHIInsertion.ll
613 Bytes
; Mem2reg should not insert dead PHI nodes! The naive algorithm inserts a PHI
; node in L3, even though there is no load of %A in anything dominated by L3.
; RUN: opt < %s -mem2reg -S | not grep phi
define void @test(i32 %B, i1 %C) {
%A = alloca i32 ; <i32*> [#uses=4]
store i32 %B, i32* %A
br i1 %C, label %L1, label %L2
L1: ; preds = %0
store i32 %B, i32* %A
%D = load i32, i32* %A ; <i32> [#uses=1]
call void @test( i32 %D, i1 false )
br label %L3
L2: ; preds = %0
%E = load i32, i32* %A ; <i32> [#uses=1]
call void @test( i32 %E, i1 true )
br label %L3
L3: ; preds = %L2, %L1
ret void
}