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; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 5
; RUN: opt -passes='print<scalar-evolution>' -scalar-evolution-classify-expressions=0 -disable-output %s 2>&1 | FileCheck %s
; The UDiv in the latch may never be executed. The backedge-taken-count
; expressions must account for the fact that evaluating the UDiv
; unconditionally may trigger UB.
define i64 @multi_exit_exit_count_with_udiv_by_value_in_latch(ptr %dst, i64 %N) {
; CHECK-LABEL: 'multi_exit_exit_count_with_udiv_by_value_in_latch'
; CHECK-NEXT: Determining loop execution counts for: @multi_exit_exit_count_with_udiv_by_value_in_latch
; CHECK-NEXT: Loop %loop.header: <multiple exits> backedge-taken count is ((0 smax %N) umin_seq (42 /u %N))
; CHECK-NEXT: exit count for loop.header: (0 smax %N)
; CHECK-NEXT: exit count for loop.latch: (42 /u %N)
; CHECK-NEXT: Loop %loop.header: constant max backedge-taken count is i64 42
; CHECK-NEXT: Loop %loop.header: symbolic max backedge-taken count is ((0 smax %N) umin_seq (42 /u %N))
; CHECK-NEXT: symbolic max exit count for loop.header: (0 smax %N)
; CHECK-NEXT: symbolic max exit count for loop.latch: (42 /u %N)
; CHECK-NEXT: Loop %loop.header: Trip multiple is 1
;
entry:
br label %loop.header
loop.header:
%iv = phi i64 [ 0, %entry ], [ %iv.next, %loop.latch ]
%gep = getelementptr inbounds i32, ptr %dst, i64 %iv
store i32 1, ptr %gep
%c.0 = icmp slt i64 %iv, %N
br i1 %c.0, label %loop.latch, label %exit
loop.latch:
%iv.next = add i64 %iv, 1
%d = udiv i64 42, %N
%c.1 = icmp slt i64 %iv, %d
br i1 %c.1, label %loop.header, label %exit
exit:
%p = phi i64 [ 1, %loop.header ], [ 0, %loop.latch]
ret i64 %p
}
; The UDiv in the latch may never be executed. The backedge-taken-count
; expressions must account for the fact that evaluating the UDiv
; unconditionally may trigger UB.
define i64 @multi_exit_exit_count_with_udiv_by_value_in_latch_different_bounds(ptr %dst, i64 %N, i64 %M) {
; CHECK-LABEL: 'multi_exit_exit_count_with_udiv_by_value_in_latch_different_bounds'
; CHECK-NEXT: Determining loop execution counts for: @multi_exit_exit_count_with_udiv_by_value_in_latch_different_bounds
; CHECK-NEXT: Loop %loop.header: <multiple exits> backedge-taken count is ((0 smax %N) umin_seq (42 /u %M))
; CHECK-NEXT: exit count for loop.header: (0 smax %N)
; CHECK-NEXT: exit count for loop.latch: (42 /u %M)
; CHECK-NEXT: Loop %loop.header: constant max backedge-taken count is i64 42
; CHECK-NEXT: Loop %loop.header: symbolic max backedge-taken count is ((0 smax %N) umin_seq (42 /u %M))
; CHECK-NEXT: symbolic max exit count for loop.header: (0 smax %N)
; CHECK-NEXT: symbolic max exit count for loop.latch: (42 /u %M)
; CHECK-NEXT: Loop %loop.header: Trip multiple is 1
;
entry:
br label %loop.header
loop.header:
%iv = phi i64 [ 0, %entry ], [ %iv.next, %loop.latch ]
%gep = getelementptr inbounds i32, ptr %dst, i64 %iv
store i32 1, ptr %gep
%c.0 = icmp slt i64 %iv, %N
br i1 %c.0, label %loop.latch, label %exit
loop.latch:
%iv.next = add i64 %iv, 1
%d = udiv i64 42, %M
%c.1 = icmp slt i64 %iv, %d
br i1 %c.1, label %loop.header, label %exit
exit:
%p = phi i64 [ 1, %loop.header ], [ 0, %loop.latch]
ret i64 %p
}
; The UDiv in the latch cannot trigger UB, evaluating it unconditionally in the
; trip count expression is fine.
define i64 @multi_exit_exit_count_with_udiv_by_constant_in_latch(ptr %dst, i64 %N) {
; CHECK-LABEL: 'multi_exit_exit_count_with_udiv_by_constant_in_latch'
; CHECK-NEXT: Determining loop execution counts for: @multi_exit_exit_count_with_udiv_by_constant_in_latch
; CHECK-NEXT: Loop %loop.header: <multiple exits> backedge-taken count is ((%N /u 42) umin (0 smax %N))
; CHECK-NEXT: exit count for loop.header: (0 smax %N)
; CHECK-NEXT: exit count for loop.latch: (%N /u 42)
; CHECK-NEXT: Loop %loop.header: constant max backedge-taken count is i64 439208192231179800
; CHECK-NEXT: Loop %loop.header: symbolic max backedge-taken count is ((%N /u 42) umin (0 smax %N))
; CHECK-NEXT: symbolic max exit count for loop.header: (0 smax %N)
; CHECK-NEXT: symbolic max exit count for loop.latch: (%N /u 42)
; CHECK-NEXT: Loop %loop.header: Trip multiple is 1
;
entry:
br label %loop.header
loop.header:
%iv = phi i64 [ 0, %entry ], [ %iv.next, %loop.latch ]
%gep = getelementptr inbounds i32, ptr %dst, i64 %iv
store i32 1, ptr %gep
%c.0 = icmp slt i64 %iv, %N
br i1 %c.0, label %loop.latch, label %exit
loop.latch:
%iv.next = add i64 %iv, 1
%d = udiv i64 %N, 42
%c.1 = icmp slt i64 %iv, %d
br i1 %c.1, label %loop.header, label %exit
exit:
%p = phi i64 [ 1, %loop.header ], [ 0, %loop.latch]
ret i64 %p
}
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