; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=instcombine -S | FileCheck %s
define i64 @test1(i32 %x) nounwind {
; CHECK-LABEL: @test1(
; CHECK-NEXT: ret i64 0
;
%y = lshr i32 %x, 1
%r = udiv i32 %y, -1
%z = sext i32 %r to i64
ret i64 %z
}
define i64 @test2(i32 %x) nounwind {
; CHECK-LABEL: @test2(
; CHECK-NEXT: ret i64 0
;
%y = lshr i32 %x, 31
%r = udiv i32 %y, 3
%z = sext i32 %r to i64
ret i64 %z
}
; The udiv instructions shouldn't be optimized away, and the
; sext instructions should be optimized to zext.
define i64 @test1_PR2274(i32 %x, i32 %g) nounwind {
; CHECK-LABEL: @test1_PR2274(
; CHECK-NEXT: [[Y:%.*]] = lshr i32 [[X:%.*]], 30
; CHECK-NEXT: [[R:%.*]] = udiv i32 [[Y]], [[G:%.*]]
; CHECK-NEXT: [[Z:%.*]] = zext nneg i32 [[R]] to i64
; CHECK-NEXT: ret i64 [[Z]]
;
%y = lshr i32 %x, 30
%r = udiv i32 %y, %g
%z = sext i32 %r to i64
ret i64 %z
}
define i64 @test2_PR2274(i32 %x, i32 %v) nounwind {
; CHECK-LABEL: @test2_PR2274(
; CHECK-NEXT: [[Y:%.*]] = lshr i32 [[X:%.*]], 31
; CHECK-NEXT: [[R:%.*]] = udiv i32 [[Y]], [[V:%.*]]
; CHECK-NEXT: [[Z:%.*]] = zext nneg i32 [[R]] to i64
; CHECK-NEXT: ret i64 [[Z]]
;
%y = lshr i32 %x, 31
%r = udiv i32 %y, %v
%z = sext i32 %r to i64
ret i64 %z
}
; The udiv should be simplified according to the rule:
; X udiv (C1 << N), where C1 is `1<<C2` --> X >> (N+C2)
@b = external global [1 x i16]
define i32 @PR30366(i1 %a) {
; CHECK-LABEL: @PR30366(
; CHECK-NEXT: [[Z:%.*]] = zext i1 [[A:%.*]] to i32
; CHECK-NEXT: [[TMP1:%.*]] = zext nneg i16 ptrtoint (ptr @b to i16) to i32
; CHECK-NEXT: [[D1:%.*]] = lshr i32 [[Z]], [[TMP1]]
; CHECK-NEXT: ret i32 [[D1]]
;
%z = zext i1 %a to i32
%shl = shl i16 1, ptrtoint (ptr @b to i16)
%z2 = zext i16 %shl to i32
%d = udiv i32 %z, %z2
ret i32 %d
}
; OSS-Fuzz #4857
; https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=4857
define i177 @ossfuzz_4857(i177 %X, i177 %Y) {
; CHECK-LABEL: @ossfuzz_4857(
; CHECK-NEXT: store i1 poison, ptr undef, align 1
; CHECK-NEXT: ret i177 0
;
%B5 = udiv i177 %Y, -1
%B4 = add i177 %B5, -1
%B2 = add i177 %B4, -1
%B6 = mul i177 %B5, %B2
%B3 = add i177 %B2, %B2
%B9 = xor i177 %B4, %B3
%B13 = ashr i177 %Y, %B2
%B22 = add i177 %B9, %B13
%B1 = udiv i177 %B5, %B6
%C9 = icmp ult i177 %Y, %B22
store i1 %C9, ptr undef
ret i177 %B1
}
; 2 low bits are not needed because 12 has 2 trailing zeros
define i8 @udiv_demanded_low_bits_set(i8 %a) {
; CHECK-LABEL: @udiv_demanded_low_bits_set(
; CHECK-NEXT: [[U:%.*]] = udiv i8 [[A:%.*]], 12
; CHECK-NEXT: ret i8 [[U]]
;
%o = or i8 %a, 3
%u = udiv i8 %o, 12
ret i8 %u
}
; This can't divide evenly, so it is poison.
define i8 @udiv_exact_demanded_low_bits_set(i8 %a) {
; CHECK-LABEL: @udiv_exact_demanded_low_bits_set(
; CHECK-NEXT: ret i8 poison
;
%o = or i8 %a, 3
%u = udiv exact i8 %o, 12
ret i8 %u
}
; All high bits are set, so this simplifies.
define i8 @udiv_demanded_high_bits_set(i8 %x, i8 %y) {
; CHECK-LABEL: @udiv_demanded_high_bits_set(
; CHECK-NEXT: ret i8 21
;
%o = or i8 %x, -4
%r = udiv i8 %o, 12
ret i8 %r
}
; This should fold the same as above.
define i8 @udiv_exact_demanded_high_bits_set(i8 %x, i8 %y) {
; CHECK-LABEL: @udiv_exact_demanded_high_bits_set(
; CHECK-NEXT: ret i8 21
;
%o = or i8 %x, -4
%r = udiv exact i8 %o, 12
ret i8 %r
}
; 2 low bits are not needed because 12 has 2 trailing zeros
define i8 @udiv_demanded_low_bits_clear(i8 %a) {
; CHECK-LABEL: @udiv_demanded_low_bits_clear(
; CHECK-NEXT: [[U:%.*]] = udiv i8 [[A:%.*]], 12
; CHECK-NEXT: ret i8 [[U]]
;
%o = and i8 %a, -4
%u = udiv i8 %o, 12
ret i8 %u
}
; This should fold the same as above.
define i8 @udiv_exact_demanded_low_bits_clear(i8 %a) {
; CHECK-LABEL: @udiv_exact_demanded_low_bits_clear(
; CHECK-NEXT: [[U:%.*]] = udiv i8 [[A:%.*]], 12
; CHECK-NEXT: ret i8 [[U]]
;
%o = and i8 %a, -4
%u = udiv exact i8 %o, 12
ret i8 %u
}
define <vscale x 1 x i32> @udiv_demanded3(<vscale x 1 x i32> %a) {
; CHECK-LABEL: @udiv_demanded3(
; CHECK-NEXT: [[U:%.*]] = udiv <vscale x 1 x i32> [[A:%.*]], shufflevector (<vscale x 1 x i32> insertelement (<vscale x 1 x i32> poison, i32 12, i64 0), <vscale x 1 x i32> poison, <vscale x 1 x i32> zeroinitializer)
; CHECK-NEXT: ret <vscale x 1 x i32> [[U]]
;
%o = or <vscale x 1 x i32> %a, splat (i32 3)
%u = udiv <vscale x 1 x i32> %o, splat (i32 12)
ret <vscale x 1 x i32> %u
}
; PR74242
define i32 @div_by_zero_or_one_from_dom_cond(i32 %a, i32 %b) {
; CHECK-LABEL: @div_by_zero_or_one_from_dom_cond(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[CMP:%.*]] = icmp ugt i32 [[A:%.*]], 1
; CHECK-NEXT: br i1 [[CMP]], label [[JOIN:%.*]], label [[ZERO_OR_ONE:%.*]]
; CHECK: zero_or_one:
; CHECK-NEXT: br label [[JOIN]]
; CHECK: join:
; CHECK-NEXT: ret i32 [[B:%.*]]
;
entry:
%cmp = icmp ugt i32 %a, 1
br i1 %cmp, label %join, label %zero_or_one
zero_or_one:
%div = udiv i32 %b, %a
br label %join
join:
%res = phi i32 [ %div, %zero_or_one ], [ %b, %entry ]
ret i32 %res
}
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