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; edgefailure - This function illustrates how SCCP is not doing it's job. This
; function should be optimized almost completely away: the loop should be
; analyzed to detect that the body executes exactly once, and thus the branch
; can be eliminated and code becomes trivially dead. This is distilled from a
; real benchmark (mst from Olden benchmark, MakeGraph function). When SCCP is
; fixed, this should be eliminated by a single SCCP application.
;
; RUN: opt %s -sccp | llvm-dis | not grep loop
define i32* @test() {
bb1:
%A = malloc i32 ; <i32*> [#uses=2]
br label %bb2
bb2: ; preds = %bb2, %bb1
;; Always 0
%i = phi i32 [ %i2, %bb2 ], [ 0, %bb1 ] ; <i32> [#uses=2]
;; Always 1
%i2 = add i32 %i, 1 ; <i32> [#uses=2]
store i32 %i, i32* %A
;; Always false
%loop = icmp sle i32 %i2, 0 ; <i1> [#uses=1]
br i1 %loop, label %bb2, label %bb3
bb3: ; preds = %bb2
ret i32* %A
}
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