; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=instcombine -S | FileCheck %s
; Fold
; x s/EXACT (-1 << y)
; to
; -(x a>>EXACT y)
define i8 @t0(i8 %x) {
; CHECK-LABEL: @t0(
; CHECK-NEXT: [[DIV_NEG:%.*]] = ashr exact i8 [[X:%.*]], 5
; CHECK-NEXT: [[DIV:%.*]] = sub nsw i8 0, [[DIV_NEG]]
; CHECK-NEXT: ret i8 [[DIV]]
;
%div = sdiv exact i8 %x, -32
ret i8 %div
}
define i8 @n1(i8 %x) {
; CHECK-LABEL: @n1(
; CHECK-NEXT: [[DIV:%.*]] = sdiv i8 [[X:%.*]], -32
; CHECK-NEXT: ret i8 [[DIV]]
;
%div = sdiv i8 %x, -32 ; not exact
ret i8 %div
}
define <2 x i8> @t2_vec_splat(<2 x i8> %x) {
; CHECK-LABEL: @t2_vec_splat(
; CHECK-NEXT: [[DIV_NEG:%.*]] = ashr exact <2 x i8> [[X:%.*]], <i8 5, i8 5>
; CHECK-NEXT: [[DIV:%.*]] = sub nsw <2 x i8> zeroinitializer, [[DIV_NEG]]
; CHECK-NEXT: ret <2 x i8> [[DIV]]
;
%div = sdiv exact <2 x i8> %x, <i8 -32, i8 -32>
ret <2 x i8> %div
}
define <2 x i8> @t3_vec(<2 x i8> %x) {
; CHECK-LABEL: @t3_vec(
; CHECK-NEXT: [[DIV_NEG:%.*]] = ashr exact <2 x i8> [[X:%.*]], <i8 5, i8 4>
; CHECK-NEXT: [[DIV:%.*]] = sub nsw <2 x i8> zeroinitializer, [[DIV_NEG]]
; CHECK-NEXT: ret <2 x i8> [[DIV]]
;
%div = sdiv exact <2 x i8> %x, <i8 -32, i8 -16>
ret <2 x i8> %div
}
define <2 x i8> @n4_vec_mixed(<2 x i8> %x) {
; CHECK-LABEL: @n4_vec_mixed(
; CHECK-NEXT: [[DIV:%.*]] = sdiv exact <2 x i8> [[X:%.*]], <i8 -32, i8 16>
; CHECK-NEXT: ret <2 x i8> [[DIV]]
;
%div = sdiv exact <2 x i8> %x, <i8 -32, i8 16>
ret <2 x i8> %div
}
define <2 x i8> @n4_vec_undef(<2 x i8> %x) {
; CHECK-LABEL: @n4_vec_undef(
; CHECK-NEXT: ret <2 x i8> poison
;
%div = sdiv exact <2 x i8> %x, <i8 -32, i8 undef>
ret <2 x i8> %div
}
define i8 @prove_exact_with_high_mask(i8 %x, i8 %y) {
; CHECK-LABEL: @prove_exact_with_high_mask(
; CHECK-NEXT: [[A:%.*]] = ashr i8 [[X:%.*]], 2
; CHECK-NEXT: [[D_NEG:%.*]] = and i8 [[A]], -8
; CHECK-NEXT: [[D:%.*]] = sub nsw i8 0, [[D_NEG]]
; CHECK-NEXT: ret i8 [[D]]
;
%a = and i8 %x, -32
%d = sdiv i8 %a, -4
ret i8 %d
}
define i8 @prove_exact_with_high_mask_limit(i8 %x, i8 %y) {
; CHECK-LABEL: @prove_exact_with_high_mask_limit(
; CHECK-NEXT: [[D_NEG:%.*]] = ashr i8 [[X:%.*]], 5
; CHECK-NEXT: [[D:%.*]] = sub nsw i8 0, [[D_NEG]]
; CHECK-NEXT: ret i8 [[D]]
;
%a = and i8 %x, -32
%d = sdiv i8 %a, -32
ret i8 %d
}
; negative test - not enough low zeros in dividend
define i8 @not_prove_exact_with_high_mask(i8 %x, i8 %y) {
; CHECK-LABEL: @not_prove_exact_with_high_mask(
; CHECK-NEXT: [[A:%.*]] = and i8 [[X:%.*]], -32
; CHECK-NEXT: [[D:%.*]] = sdiv i8 [[A]], -64
; CHECK-NEXT: ret i8 [[D]]
;
%a = and i8 %x, -32
%d = sdiv i8 %a, -64
ret i8 %d
}
define <2 x i8> @prove_exact_with_high_mask_splat_vec(<2 x i8> %x, <2 x i8> %y) {
; CHECK-LABEL: @prove_exact_with_high_mask_splat_vec(
; CHECK-NEXT: [[A:%.*]] = shl <2 x i8> [[X:%.*]], <i8 5, i8 5>
; CHECK-NEXT: [[D_NEG:%.*]] = ashr exact <2 x i8> [[A]], <i8 4, i8 4>
; CHECK-NEXT: [[D:%.*]] = sub nsw <2 x i8> zeroinitializer, [[D_NEG]]
; CHECK-NEXT: ret <2 x i8> [[D]]
;
%a = shl <2 x i8> %x, <i8 5, i8 5>
%d = sdiv <2 x i8> %a, <i8 -16, i8 -16>
ret <2 x i8> %d
}
; TODO: Needs knownbits to handle arbitrary vector constants.
define <2 x i8> @prove_exact_with_high_mask_vec(<2 x i8> %x, <2 x i8> %y) {
; CHECK-LABEL: @prove_exact_with_high_mask_vec(
; CHECK-NEXT: [[A:%.*]] = shl <2 x i8> [[X:%.*]], <i8 3, i8 2>
; CHECK-NEXT: [[D:%.*]] = sdiv <2 x i8> [[A]], <i8 -8, i8 -4>
; CHECK-NEXT: ret <2 x i8> [[D]]
;
%a = shl <2 x i8> %x, <i8 3, i8 2>
%d = sdiv <2 x i8> %a, <i8 -8, i8 -4>
ret <2 x i8> %d
}
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