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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instsimplify -S | FileCheck %s
define i32 @zero_dividend(i32 %A) {
; CHECK-LABEL: @zero_dividend(
; CHECK-NEXT: ret i32 0
;
%B = sdiv i32 0, %A
ret i32 %B
}
define <2 x i32> @zero_dividend_vector(<2 x i32> %A) {
; CHECK-LABEL: @zero_dividend_vector(
; CHECK-NEXT: ret <2 x i32> zeroinitializer
;
%B = udiv <2 x i32> zeroinitializer, %A
ret <2 x i32> %B
}
define <2 x i32> @zero_dividend_vector_undef_elt(<2 x i32> %A) {
; CHECK-LABEL: @zero_dividend_vector_undef_elt(
; CHECK-NEXT: ret <2 x i32> zeroinitializer
;
%B = sdiv <2 x i32> <i32 0, i32 undef>, %A
ret <2 x i32> %B
}
; Division-by-zero is poison. UB in any vector lane means the whole op is poison.
define <2 x i8> @sdiv_zero_elt_vec_constfold(<2 x i8> %x) {
; CHECK-LABEL: @sdiv_zero_elt_vec_constfold(
; CHECK-NEXT: ret <2 x i8> poison
;
%div = sdiv <2 x i8> <i8 1, i8 2>, <i8 0, i8 -42>
ret <2 x i8> %div
}
define <2 x i8> @udiv_zero_elt_vec_constfold(<2 x i8> %x) {
; CHECK-LABEL: @udiv_zero_elt_vec_constfold(
; CHECK-NEXT: ret <2 x i8> poison
;
%div = udiv <2 x i8> <i8 1, i8 2>, <i8 42, i8 0>
ret <2 x i8> %div
}
define <2 x i8> @sdiv_zero_elt_vec(<2 x i8> %x) {
; CHECK-LABEL: @sdiv_zero_elt_vec(
; CHECK-NEXT: ret <2 x i8> poison
;
%div = sdiv <2 x i8> %x, <i8 -42, i8 0>
ret <2 x i8> %div
}
define <2 x i8> @udiv_zero_elt_vec(<2 x i8> %x) {
; CHECK-LABEL: @udiv_zero_elt_vec(
; CHECK-NEXT: ret <2 x i8> poison
;
%div = udiv <2 x i8> %x, <i8 0, i8 42>
ret <2 x i8> %div
}
define <2 x i8> @sdiv_undef_elt_vec(<2 x i8> %x) {
; CHECK-LABEL: @sdiv_undef_elt_vec(
; CHECK-NEXT: ret <2 x i8> poison
;
%div = sdiv <2 x i8> %x, <i8 -42, i8 undef>
ret <2 x i8> %div
}
define <2 x i8> @udiv_undef_elt_vec(<2 x i8> %x) {
; CHECK-LABEL: @udiv_undef_elt_vec(
; CHECK-NEXT: ret <2 x i8> poison
;
%div = udiv <2 x i8> %x, <i8 undef, i8 42>
ret <2 x i8> %div
}
; Division-by-zero is undef. UB in any vector lane means the whole op is undef.
; Thus, we can simplify this: if any element of 'y' is 0, we can do anything.
; Therefore, assume that all elements of 'y' must be 1.
define <2 x i1> @sdiv_bool_vec(<2 x i1> %x, <2 x i1> %y) {
; CHECK-LABEL: @sdiv_bool_vec(
; CHECK-NEXT: ret <2 x i1> [[X:%.*]]
;
%div = sdiv <2 x i1> %x, %y
ret <2 x i1> %div
}
define <2 x i1> @udiv_bool_vec(<2 x i1> %x, <2 x i1> %y) {
; CHECK-LABEL: @udiv_bool_vec(
; CHECK-NEXT: ret <2 x i1> [[X:%.*]]
;
%div = udiv <2 x i1> %x, %y
ret <2 x i1> %div
}
define i32 @zext_bool_udiv_divisor(i1 %x, i32 %y) {
; CHECK-LABEL: @zext_bool_udiv_divisor(
; CHECK-NEXT: ret i32 [[Y:%.*]]
;
%ext = zext i1 %x to i32
%r = udiv i32 %y, %ext
ret i32 %r
}
define <2 x i32> @zext_bool_sdiv_divisor_vec(<2 x i1> %x, <2 x i32> %y) {
; CHECK-LABEL: @zext_bool_sdiv_divisor_vec(
; CHECK-NEXT: ret <2 x i32> [[Y:%.*]]
;
%ext = zext <2 x i1> %x to <2 x i32>
%r = sdiv <2 x i32> %y, %ext
ret <2 x i32> %r
}
define i32 @udiv_dividend_known_smaller_than_constant_divisor(i32 %x) {
; CHECK-LABEL: @udiv_dividend_known_smaller_than_constant_divisor(
; CHECK-NEXT: ret i32 0
;
%and = and i32 %x, 250
%div = udiv i32 %and, 251
ret i32 %div
}
define i32 @not_udiv_dividend_known_smaller_than_constant_divisor(i32 %x) {
; CHECK-LABEL: @not_udiv_dividend_known_smaller_than_constant_divisor(
; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 251
; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[AND]], 251
; CHECK-NEXT: ret i32 [[DIV]]
;
%and = and i32 %x, 251
%div = udiv i32 %and, 251
ret i32 %div
}
define i32 @udiv_constant_dividend_known_smaller_than_divisor(i32 %x) {
; CHECK-LABEL: @udiv_constant_dividend_known_smaller_than_divisor(
; CHECK-NEXT: ret i32 0
;
%or = or i32 %x, 251
%div = udiv i32 250, %or
ret i32 %div
}
define i32 @not_udiv_constant_dividend_known_smaller_than_divisor(i32 %x) {
; CHECK-LABEL: @not_udiv_constant_dividend_known_smaller_than_divisor(
; CHECK-NEXT: [[OR:%.*]] = or i32 [[X:%.*]], 251
; CHECK-NEXT: [[DIV:%.*]] = udiv i32 251, [[OR]]
; CHECK-NEXT: ret i32 [[DIV]]
;
%or = or i32 %x, 251
%div = udiv i32 251, %or
ret i32 %div
}
define i8 @udiv_dividend_known_smaller_than_constant_divisor2(i1 %b) {
; CHECK-LABEL: @udiv_dividend_known_smaller_than_constant_divisor2(
; CHECK-NEXT: ret i8 0
;
%t0 = zext i1 %b to i8
%xor = xor i8 %t0, 12
%r = udiv i8 %xor, 14
ret i8 %r
}
; negative test - dividend can equal 13
define i8 @not_udiv_dividend_known_smaller_than_constant_divisor2(i1 %b) {
; CHECK-LABEL: @not_udiv_dividend_known_smaller_than_constant_divisor2(
; CHECK-NEXT: [[T0:%.*]] = zext i1 [[B:%.*]] to i8
; CHECK-NEXT: [[XOR:%.*]] = xor i8 [[T0]], 12
; CHECK-NEXT: [[R:%.*]] = udiv i8 [[XOR]], 13
; CHECK-NEXT: ret i8 [[R]]
;
%t0 = zext i1 %b to i8
%xor = xor i8 %t0, 12
%r = udiv i8 %xor, 13
ret i8 %r
}
; This would require computing known bits on both x and y. Is it worth doing?
define i32 @udiv_dividend_known_smaller_than_divisor(i32 %x, i32 %y) {
; CHECK-LABEL: @udiv_dividend_known_smaller_than_divisor(
; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 250
; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 251
; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[AND]], [[OR]]
; CHECK-NEXT: ret i32 [[DIV]]
;
%and = and i32 %x, 250
%or = or i32 %y, 251
%div = udiv i32 %and, %or
ret i32 %div
}
define i32 @not_udiv_dividend_known_smaller_than_divisor(i32 %x, i32 %y) {
; CHECK-LABEL: @not_udiv_dividend_known_smaller_than_divisor(
; CHECK-NEXT: [[AND:%.*]] = and i32 [[X:%.*]], 251
; CHECK-NEXT: [[OR:%.*]] = or i32 [[Y:%.*]], 251
; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[AND]], [[OR]]
; CHECK-NEXT: ret i32 [[DIV]]
;
%and = and i32 %x, 251
%or = or i32 %y, 251
%div = udiv i32 %and, %or
ret i32 %div
}
declare i32 @external()
define i32 @div1() {
; CHECK-LABEL: @div1(
; CHECK-NEXT: [[CALL:%.*]] = call i32 @external(), !range [[RNG0:![0-9]+]]
; CHECK-NEXT: ret i32 0
;
%call = call i32 @external(), !range !0
%urem = udiv i32 %call, 3
ret i32 %urem
}
define i8 @sdiv_minusone_divisor() {
; CHECK-LABEL: @sdiv_minusone_divisor(
; CHECK-NEXT: ret i8 poison
;
%v = sdiv i8 -128, -1
ret i8 %v
}
!0 = !{i32 0, i32 3}
|
