xref: /aosp_15_r20/external/llvm/test/Transforms/LoopUnroll/2011-10-01-NoopTrunc.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)

; RUN: opt < %s -S -loop-unroll -unroll-threshold=150 | FileCheck %s
;
; Verify that trunc i64 to i32 is considered free by loop unrolling
; heuristics when i32 is a native type.
; This should result in full unrolling this loop with size=7, TC=19.
; If the trunc were not free we would have 8*19=152 > 150.

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"

; Check that for.body was unrolled 19 times.
; CHECK-LABEL: @test(
; CHECK: %0 = load
; CHECK: %conv = sext i8 %0 to i32
; CHECK: %add.1 = add nsw i32 %conv.1, %conv
; CHECK: %add.18 = add nsw i32 %conv.18, %add.17
; CHECK: ret i32 %add.18
define i32 @test(i8* %arr) nounwind uwtable readnone {
entry:
  br label %for.body

for.body:                                         ; preds = %for.body, %entry
  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
  %sum.02 = phi i32 [ 0, %entry ], [ %add, %for.body ]
  %arrayidx = getelementptr inbounds i8, i8* %arr, i64 %indvars.iv
  %0 = load i8, i8* %arrayidx, align 1
  %conv = sext i8 %0 to i32
  %add = add nsw i32 %conv, %sum.02
  %indvars.iv.next = add i64 %indvars.iv, 1
  %lftr.wideiv1 = trunc i64 %indvars.iv.next to i32
  %exitcond2 = icmp eq i32 %lftr.wideiv1, 19
  br i1 %exitcond2, label %for.end, label %for.body

for.end:                                          ; preds = %for.body
  %add.lcssa = phi i32 [ %add, %for.body ]
  ret i32 %add.lcssa
}