38 lines
1 KiB
LLVM
38 lines
1 KiB
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
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; RUN: opt < %s -passes=instcombine -S | FileCheck %s
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; Pattern:
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; (or (and (add x, half_c1), c3), (and x, c2))
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; IFF:
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; c1, c2, c3 is constant
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; c1 is pow2
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; c2 < c1
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; c3 == (c1 - 1) ^ c2
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; half_c1 == (lshr c1, 1)
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; (c1 >> 1) & c3 == (c1 >> 1)
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; x is known to be less than c1
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; Could be transformed into:
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; (xor x, half_c1)
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; The reason above transformation could be done is becase
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; in (and (add x, half_c1), c3), half_c1 equals the top bit
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; of the demanded mask indicated by (and ..., c3)
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define i16 @or_and_add_and() {
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; CHECK-LABEL: @or_and_add_and(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: [[X:%.*]] = call i16 @dummy(), !range [[RNG0:![0-9]+]]
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; CHECK-NEXT: [[OR:%.*]] = xor i16 [[X]], 32
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; CHECK-NEXT: ret i16 [[OR]]
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;
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entry:
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%x = call i16 @dummy(), !range !0
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%add = add i16 32, %x
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%and1 = and i16 %add, 48
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%and2 = and i16 %x, 15
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%or = or i16 %and1, %and2
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ret i16 %or
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}
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declare i16 @dummy()
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!0 = !{i16 0, i16 64}
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