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| ; RUN: opt < %s -S -loop-unroll -unroll-threshold=50 | FileCheck %s
; Make sure this loop is completely unrolled...
; CHECK-LABEL: @test1
; CHECK: for.body:
; CHECK-NOT: for.end:
define i32 @test1(i32* nocapture %a) nounwind uwtable readonly {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
%sum.01 = phi i32 [ 0, %entry ], [ %add, %for.body ]
%arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
%0 = load i32, i32* %arrayidx, align 4
; This loop will be completely unrolled, even with these extra instructions,
; but only because they're ephemeral (and, thus, free).
%1 = add nsw i32 %0, 2
%2 = add nsw i32 %1, 4
%3 = add nsw i32 %2, 4
%4 = add nsw i32 %3, 4
%5 = add nsw i32 %4, 4
%6 = add nsw i32 %5, 4
%7 = add nsw i32 %6, 4
%8 = add nsw i32 %7, 4
%9 = add nsw i32 %8, 4
%10 = add nsw i32 %9, 4
%ca = icmp sgt i32 %10, -7
call void @llvm.assume(i1 %ca)
%add = add nsw i32 %0, %sum.01
%indvars.iv.next = add i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, 5
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret i32 %add
}
declare void @llvm.assume(i1) nounwind
|