2011-10-01-NoopTrunc.ll 1.5 KB

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  1. ; RUN: opt < %s -S -loop-unroll -unroll-threshold=150 | FileCheck %s
  2. ;
  3. ; Verify that trunc i64 to i32 is considered free by loop unrolling
  4. ; heuristics when i32 is a native type.
  5. ; This should result in full unrolling this loop with size=7, TC=19.
  6. ; If the trunc were not free we would have 8*19=152 > 150.
  7. target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
  8. ; Check that for.body was unrolled 19 times.
  9. ; CHECK-LABEL: @test(
  10. ; CHECK: %0 = load
  11. ; CHECK: %conv = sext i8 %0 to i32
  12. ; CHECK: %add.1 = add nsw i32 %conv.1, %conv
  13. ; CHECK: %add.18 = add nsw i32 %conv.18, %add.17
  14. ; CHECK: ret i32 %add.18
  15. define i32 @test(i8* %arr) nounwind uwtable readnone {
  16. entry:
  17. br label %for.body
  18. for.body: ; preds = %for.body, %entry
  19. %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
  20. %sum.02 = phi i32 [ 0, %entry ], [ %add, %for.body ]
  21. %arrayidx = getelementptr inbounds i8, i8* %arr, i64 %indvars.iv
  22. %0 = load i8, i8* %arrayidx, align 1
  23. %conv = sext i8 %0 to i32
  24. %add = add nsw i32 %conv, %sum.02
  25. %indvars.iv.next = add i64 %indvars.iv, 1
  26. %lftr.wideiv1 = trunc i64 %indvars.iv.next to i32
  27. %exitcond2 = icmp eq i32 %lftr.wideiv1, 19
  28. br i1 %exitcond2, label %for.end, label %for.body
  29. for.end: ; preds = %for.body
  30. %add.lcssa = phi i32 [ %add, %for.body ]
  31. ret i32 %add.lcssa
  32. }