unknown_phis.ll
1.58 KB
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; RUN: opt < %s -analyze -scalar-evolution | FileCheck %s
define void @merge_values_with_ranges(i32 *%a_len_ptr, i32 *%b_len_ptr, i1 %unknown_cond) {
; CHECK-LABEL: Classifying expressions for: @merge_values_with_ranges
; CHECK: %len = phi i32 [ %len_a, %if.true ], [ %len_b, %if.false ]
; CHECK-NEXT: --> %len U: [0,2147483647) S: [0,2147483647)
entry:
br i1 %unknown_cond, label %if.true, label %if.false
if.true:
%len_a = load i32, i32* %a_len_ptr, !range !0
br label %merge
if.false:
%len_b = load i32, i32* %b_len_ptr, !range !0
br label %merge
merge:
%len = phi i32 [ %len_a, %if.true ], [ %len_b, %if.false ]
ret void
}
define void @merge_values_with_ranges_looped(i32 *%a_len_ptr, i32 *%b_len_ptr) {
; TODO: We could be much smarter here. So far we just make sure that we do not
; go into infinite loop analyzing these Phis.
; CHECK-LABEL: Classifying expressions for: @merge_values_with_ranges_looped
; CHECK: %p1 = phi i32 [ %len_a, %entry ], [ %p2, %loop ]
; CHECK-NEXT: --> %p1 U: full-set S: full-set
; CHECK: %p2 = phi i32 [ %len_b, %entry ], [ %p1, %loop ]
; CHECK-NEXT: --> %p2 U: full-set S: full-set
entry:
%len_a = load i32, i32* %a_len_ptr, !range !0
%len_b = load i32, i32* %b_len_ptr, !range !0
br label %loop
loop:
%p1 = phi i32 [ %len_a, %entry ], [ %p2, %loop ]
%p2 = phi i32 [ %len_b, %entry ], [ %p1, %loop ]
%iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ]
%iv.next = add i32 %iv, 1
%loop.cond = icmp slt i32 %iv.next, 100
br i1 %loop.cond, label %loop, label %exit
exit:
ret void
}
!0 = !{i32 0, i32 2147483647}