llvm-project/llvm/test/Transforms/IndVarSimplify/loop_evaluate_6.ll

32 lines
1016 B
LLVM

; RUN: llvm-as < %s | opt -indvars -loop-deletion | llvm-dis | grep phi | count 1
; XFAIL: *
; Indvars can't evaluate this loop, because ScalarEvolution can't compute
; an exact trip count, because it doesn't know if dividing by the stride will
; have a remainder. It could be done with more aggressive VRP though.
define i32 @test(i32 %x_offs) nounwind readnone {
entry:
%0 = icmp sgt i32 %x_offs, 4 ; <i1> [#uses=1]
br i1 %0, label %bb.nph, label %bb2
bb.nph: ; preds = %entry
br label %bb
bb: ; preds = %bb1, %bb.nph
%x_offs_addr.01 = phi i32 [ %1, %bb1 ], [ %x_offs, %bb.nph ] ; <i32> [#uses=1]
%1 = add i32 %x_offs_addr.01, -4 ; <i32> [#uses=3]
br label %bb1
bb1: ; preds = %bb
%2 = icmp sgt i32 %1, 4 ; <i1> [#uses=1]
br i1 %2, label %bb, label %bb1.bb2_crit_edge
bb1.bb2_crit_edge: ; preds = %bb1
br label %bb2
bb2: ; preds = %bb1.bb2_crit_edge, %entry
%x_offs_addr.0.lcssa = phi i32 [ %1, %bb1.bb2_crit_edge ], [ %x_offs, %entry ] ; <i32> [#uses=1]
ret i32 %x_offs_addr.0.lcssa
}