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; RUN: opt -passes=globalopt -S < %s | FileCheck %s
@G1 = internal global i32 5
@G2 = internal global i32 5
@G3 = internal global i32 5
@G4 = internal global i32 5
@G5 = internal global i32 5
; CHECK-LABEL: @test1
define internal i32 @test1() norecurse {
; CHECK-NOT: @G1
store i32 4, ptr @G1
%a = load i32, ptr @G1
; CHECK: ret
ret i32 %a
}
; The load comes before the store which makes @G2 live before the call.
; CHECK-LABEL: @test2
define internal i32 @test2() norecurse {
; CHECK-NOT: %G2
%a = load i32, ptr @G2
store i32 4, ptr @G2
; CHECK: ret
ret i32 %a
}
; This global is indexed by a GEP - this makes it partial alias and we bail out.
; FIXME: We don't actually have to bail out in this case.
; CHECK-LABEL: @test3
define internal i32 @test3() norecurse {
; CHECK-NOT: %G3
%a = load i32, ptr @G3
store i32 4, ptr @G3
; CHECK: ret
ret i32 %a
}
; The global is casted away to a larger type then loaded. The store only partially
; covers the load, so we must not demote.
; CHECK-LABEL: @test4
define internal i32 @test4() norecurse {
; CHECK-NOT: %G4
store i32 4, ptr @G4
%a = load i64, ptr @G4
%b = trunc i64 %a to i32
; CHECK: ret
ret i32 %b
}
; The global is casted away to a smaller type then loaded. This one is fine.
; CHECK-LABEL: @test5
define internal i32 @test5() norecurse {
; CHECK-NOT: @G5
store i32 4, ptr @G5
%a = load i16, ptr @G5
%b = zext i16 %a to i32
; CHECK: ret
ret i32 %b
}
define i32 @main() norecurse {
%a = call i32 @test1()
%b = call i32 @test2()
%c = call i32 @test3()
%d = call i32 @test4()
%e = call i32 @test5()
%x = or i32 %a, %b
%y = or i32 %x, %c
%z = or i32 %y, %d
%w = or i32 %z, %e
ret i32 %w
}
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