; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; This test makes sure that div instructions are properly eliminated. ; RUN: opt < %s -instcombine -S | FileCheck %s define i32 @test1(i32 %A) { ; CHECK-LABEL: @test1( ; CHECK-NEXT: ret i32 [[A:%.*]] ; %B = sdiv i32 %A, 1 ret i32 %B } define i32 @test2(i32 %A) { ; CHECK-LABEL: @test2( ; CHECK-NEXT: [[B:%.*]] = lshr i32 [[A:%.*]], 3 ; CHECK-NEXT: ret i32 [[B]] ; %B = udiv i32 %A, 8 ret i32 %B } define i32 @sdiv_by_minus1(i32 %A) { ; CHECK-LABEL: @sdiv_by_minus1( ; CHECK-NEXT: [[B:%.*]] = sub i32 0, [[A:%.*]] ; CHECK-NEXT: ret i32 [[B]] ; %B = sdiv i32 %A, -1 ret i32 %B } define <2 x i64> @sdiv_by_minus1_vec(<2 x i64> %x) { ; CHECK-LABEL: @sdiv_by_minus1_vec( ; CHECK-NEXT: [[DIV:%.*]] = sub <2 x i64> zeroinitializer, [[X:%.*]] ; CHECK-NEXT: ret <2 x i64> [[DIV]] ; %div = sdiv <2 x i64> %x, ret <2 x i64> %div } define <2 x i64> @sdiv_by_minus1_vec_undef_elt(<2 x i64> %x) { ; CHECK-LABEL: @sdiv_by_minus1_vec_undef_elt( ; CHECK-NEXT: ret <2 x i64> undef ; %div = sdiv <2 x i64> %x, ret <2 x i64> %div } define i32 @sdiv_by_sext_minus1(i1 %x, i32 %y) { ; CHECK-LABEL: @sdiv_by_sext_minus1( ; CHECK-NEXT: [[DIV:%.*]] = sub i32 0, [[Y:%.*]] ; CHECK-NEXT: ret i32 [[DIV]] ; %sext = sext i1 %x to i32 %div = sdiv i32 %y, %sext ret i32 %div } define <2 x i32> @sdiv_by_sext_minus1_vec(<2 x i1> %x, <2 x i32> %y) { ; CHECK-LABEL: @sdiv_by_sext_minus1_vec( ; CHECK-NEXT: [[DIV:%.*]] = sub <2 x i32> zeroinitializer, [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[DIV]] ; %sext = sext <2 x i1> %x to <2 x i32> %div = sdiv <2 x i32> %y, %sext ret <2 x i32> %div } define i8 @udiv_by_negative(i8 %x) { ; CHECK-LABEL: @udiv_by_negative( ; CHECK-NEXT: [[TMP1:%.*]] = icmp ugt i8 [[X:%.*]], -7 ; CHECK-NEXT: [[A:%.*]] = zext i1 [[TMP1]] to i8 ; CHECK-NEXT: ret i8 [[A]] ; %A = udiv i8 %x, 250 ret i8 %A } define i32 @udiv_by_minus1(i32 %A) { ; CHECK-LABEL: @udiv_by_minus1( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[A:%.*]], -1 ; CHECK-NEXT: [[B:%.*]] = zext i1 [[TMP1]] to i32 ; CHECK-NEXT: ret i32 [[B]] ; %B = udiv i32 %A, -1 ret i32 %B } define <2 x i64> @udiv_by_minus1_vec(<2 x i64> %x) { ; CHECK-LABEL: @udiv_by_minus1_vec( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq <2 x i64> [[X:%.*]], ; CHECK-NEXT: [[DIV:%.*]] = zext <2 x i1> [[TMP1]] to <2 x i64> ; CHECK-NEXT: ret <2 x i64> [[DIV]] ; %div = udiv <2 x i64> %x, ret <2 x i64> %div } define i32 @udiv_by_sext_all_ones(i1 %x, i32 %y) { ; CHECK-LABEL: @udiv_by_sext_all_ones( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[Y:%.*]], -1 ; CHECK-NEXT: [[DIV:%.*]] = zext i1 [[TMP1]] to i32 ; CHECK-NEXT: ret i32 [[DIV]] ; %sext = sext i1 %x to i32 %div = udiv i32 %y, %sext ret i32 %div } define <2 x i32> @udiv_by_sext_all_ones_vec(<2 x i1> %x, <2 x i32> %y) { ; CHECK-LABEL: @udiv_by_sext_all_ones_vec( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq <2 x i32> [[Y:%.*]], ; CHECK-NEXT: [[DIV:%.*]] = zext <2 x i1> [[TMP1]] to <2 x i32> ; CHECK-NEXT: ret <2 x i32> [[DIV]] ; %sext = sext <2 x i1> %x to <2 x i32> %div = udiv <2 x i32> %y, %sext ret <2 x i32> %div } define i32 @test5(i32 %A) { ; CHECK-LABEL: @test5( ; CHECK-NEXT: ret i32 0 ; %B = udiv i32 %A, -16 %C = udiv i32 %B, -4 ret i32 %C } define i1 @test6(i32 %A) { ; CHECK-LABEL: @test6( ; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[A:%.*]], 123 ; CHECK-NEXT: ret i1 [[TMP1]] ; %B = udiv i32 %A, 123 ; A < 123 %C = icmp eq i32 %B, 0 ret i1 %C } define i1 @test7(i32 %A) { ; CHECK-LABEL: @test7( ; CHECK-NEXT: [[A_OFF:%.*]] = add i32 [[A:%.*]], -20 ; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[A_OFF]], 10 ; CHECK-NEXT: ret i1 [[TMP1]] ; %B = udiv i32 %A, 10 ; A >= 20 && A < 30 %C = icmp eq i32 %B, 2 ret i1 %C } define <2 x i1> @test7vec(<2 x i32> %A) { ; CHECK-LABEL: @test7vec( ; CHECK-NEXT: [[A_OFF:%.*]] = add <2 x i32> [[A:%.*]], ; CHECK-NEXT: [[TMP1:%.*]] = icmp ult <2 x i32> [[A_OFF]], ; CHECK-NEXT: ret <2 x i1> [[TMP1]] ; %B = udiv <2 x i32> %A, %C = icmp eq <2 x i32> %B, ret <2 x i1> %C } define i1 @test8(i8 %A) { ; CHECK-LABEL: @test8( ; CHECK-NEXT: [[C:%.*]] = icmp ugt i8 [[A:%.*]], -11 ; CHECK-NEXT: ret i1 [[C]] ; %B = udiv i8 %A, 123 ; A >= 246 %C = icmp eq i8 %B, 2 ret i1 %C } define <2 x i1> @test8vec(<2 x i8> %A) { ; CHECK-LABEL: @test8vec( ; CHECK-NEXT: [[C:%.*]] = icmp ugt <2 x i8> [[A:%.*]], ; CHECK-NEXT: ret <2 x i1> [[C]] ; %B = udiv <2 x i8> %A, %C = icmp eq <2 x i8> %B, ret <2 x i1> %C } define i1 @test9(i8 %A) { ; CHECK-LABEL: @test9( ; CHECK-NEXT: [[C:%.*]] = icmp ult i8 [[A:%.*]], -10 ; CHECK-NEXT: ret i1 [[C]] ; %B = udiv i8 %A, 123 ; A < 246 %C = icmp ne i8 %B, 2 ret i1 %C } define <2 x i1> @test9vec(<2 x i8> %A) { ; CHECK-LABEL: @test9vec( ; CHECK-NEXT: [[C:%.*]] = icmp ult <2 x i8> [[A:%.*]], ; CHECK-NEXT: ret <2 x i1> [[C]] ; %B = udiv <2 x i8> %A, %C = icmp ne <2 x i8> %B, ret <2 x i1> %C } define i32 @test10(i32 %X, i1 %C) { ; CHECK-LABEL: @test10( ; CHECK-NEXT: [[R_V:%.*]] = select i1 [[C:%.*]], i32 6, i32 3 ; CHECK-NEXT: [[R:%.*]] = lshr i32 [[X:%.*]], [[R_V]] ; CHECK-NEXT: ret i32 [[R]] ; %V = select i1 %C, i32 64, i32 8 %R = udiv i32 %X, %V ret i32 %R } define i32 @test11(i32 %X, i1 %C) { ; CHECK-LABEL: @test11( ; CHECK-NEXT: [[B_V:%.*]] = select i1 [[C:%.*]], i32 10, i32 5 ; CHECK-NEXT: [[B:%.*]] = lshr i32 [[X:%.*]], [[B_V]] ; CHECK-NEXT: ret i32 [[B]] ; %A = select i1 %C, i32 1024, i32 32 %B = udiv i32 %X, %A ret i32 %B } ; PR2328 define i32 @test12(i32 %x) { ; CHECK-LABEL: @test12( ; CHECK-NEXT: ret i32 1 ; %tmp3 = udiv i32 %x, %x ; 1 ret i32 %tmp3 } define i32 @test13(i32 %x) { ; CHECK-LABEL: @test13( ; CHECK-NEXT: ret i32 1 ; %tmp3 = sdiv i32 %x, %x ; 1 ret i32 %tmp3 } define i32 @test14(i8 %x) { ; CHECK-LABEL: @test14( ; CHECK-NEXT: ret i32 0 ; %zext = zext i8 %x to i32 %div = udiv i32 %zext, 257 ; 0 ret i32 %div } ; PR9814 define i32 @test15(i32 %a, i32 %b) { ; CHECK-LABEL: @test15( ; CHECK-NEXT: [[TMP1:%.*]] = add i32 [[B:%.*]], -2 ; CHECK-NEXT: [[DIV2:%.*]] = lshr i32 [[A:%.*]], [[TMP1]] ; CHECK-NEXT: ret i32 [[DIV2]] ; %shl = shl i32 1, %b %div = lshr i32 %shl, 2 %div2 = udiv i32 %a, %div ret i32 %div2 } define <2 x i64> @test16(<2 x i64> %x) { ; CHECK-LABEL: @test16( ; CHECK-NEXT: [[DIV:%.*]] = udiv <2 x i64> [[X:%.*]], ; CHECK-NEXT: ret <2 x i64> [[DIV]] ; %shr = lshr <2 x i64> %x, %div = udiv <2 x i64> %shr, ret <2 x i64> %div } define <2 x i64> @test17(<2 x i64> %x) { ; CHECK-LABEL: @test17( ; CHECK-NEXT: [[DIV:%.*]] = sdiv <2 x i64> [[X:%.*]], ; CHECK-NEXT: ret <2 x i64> [[DIV]] ; %neg = sub nsw <2 x i64> zeroinitializer, %x %div = sdiv <2 x i64> %neg, ret <2 x i64> %div } define i32 @test19(i32 %x) { ; CHECK-LABEL: @test19( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[X:%.*]], 1 ; CHECK-NEXT: [[A:%.*]] = zext i1 [[TMP1]] to i32 ; CHECK-NEXT: ret i32 [[A]] ; %A = udiv i32 1, %x ret i32 %A } define <2 x i32> @test19vec(<2 x i32> %x) { ; CHECK-LABEL: @test19vec( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[A:%.*]] = zext <2 x i1> [[TMP1]] to <2 x i32> ; CHECK-NEXT: ret <2 x i32> [[A]] ; %A = udiv <2 x i32> , %x ret <2 x i32> %A } define i32 @test20(i32 %x) { ; CHECK-LABEL: @test20( ; CHECK-NEXT: [[TMP1:%.*]] = add i32 [[X:%.*]], 1 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i32 [[TMP1]], 3 ; CHECK-NEXT: [[A:%.*]] = select i1 [[TMP2]], i32 [[X]], i32 0 ; CHECK-NEXT: ret i32 [[A]] ; %A = sdiv i32 1, %x ret i32 %A } define <2 x i32> @test20vec(<2 x i32> %x) { ; CHECK-LABEL: @test20vec( ; CHECK-NEXT: [[TMP1:%.*]] = add <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult <2 x i32> [[TMP1]], ; CHECK-NEXT: [[A:%.*]] = select <2 x i1> [[TMP2]], <2 x i32> [[X]], <2 x i32> zeroinitializer ; CHECK-NEXT: ret <2 x i32> [[A]] ; %A = sdiv <2 x i32> , %x ret <2 x i32> %A } define i32 @test21(i32 %a) { ; CHECK-LABEL: @test21( ; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[A:%.*]], 3 ; CHECK-NEXT: ret i32 [[DIV]] ; %shl = shl nsw i32 %a, 2 %div = sdiv i32 %shl, 12 ret i32 %div } define i32 @test22(i32 %a) { ; CHECK-LABEL: @test22( ; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[A:%.*]], 4 ; CHECK-NEXT: ret i32 [[DIV]] ; %mul = mul nsw i32 %a, 3 %div = sdiv i32 %mul, 12 ret i32 %div } define i32 @test23(i32 %a) { ; CHECK-LABEL: @test23( ; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[A:%.*]], 3 ; CHECK-NEXT: ret i32 [[DIV]] ; %shl = shl nuw i32 %a, 2 %div = udiv i32 %shl, 12 ret i32 %div } define i32 @test24(i32 %a) { ; CHECK-LABEL: @test24( ; CHECK-NEXT: [[DIV:%.*]] = lshr i32 [[A:%.*]], 2 ; CHECK-NEXT: ret i32 [[DIV]] ; %mul = mul nuw i32 %a, 3 %div = udiv i32 %mul, 12 ret i32 %div } define i32 @test25(i32 %a) { ; CHECK-LABEL: @test25( ; CHECK-NEXT: [[DIV:%.*]] = shl nsw i32 [[A:%.*]], 1 ; CHECK-NEXT: ret i32 [[DIV]] ; %shl = shl nsw i32 %a, 2 %div = sdiv i32 %shl, 2 ret i32 %div } define i32 @test26(i32 %a) { ; CHECK-LABEL: @test26( ; CHECK-NEXT: [[DIV:%.*]] = shl nsw i32 [[A:%.*]], 2 ; CHECK-NEXT: ret i32 [[DIV]] ; %mul = mul nsw i32 %a, 12 %div = sdiv i32 %mul, 3 ret i32 %div } define i32 @test27(i32 %a) { ; CHECK-LABEL: @test27( ; CHECK-NEXT: [[DIV:%.*]] = shl nuw i32 [[A:%.*]], 1 ; CHECK-NEXT: ret i32 [[DIV]] ; %shl = shl nuw i32 %a, 2 %div = udiv i32 %shl, 2 ret i32 %div } define i32 @test28(i32 %a) { ; CHECK-LABEL: @test28( ; CHECK-NEXT: [[DIV:%.*]] = mul nuw i32 [[A:%.*]], 12 ; CHECK-NEXT: ret i32 [[DIV]] ; %mul = mul nuw i32 %a, 36 %div = udiv i32 %mul, 3 ret i32 %div } define i32 @test29(i32 %a) { ; CHECK-LABEL: @test29( ; CHECK-NEXT: [[MUL_LOBIT:%.*]] = and i32 [[A:%.*]], 1 ; CHECK-NEXT: ret i32 [[MUL_LOBIT]] ; %mul = shl nsw i32 %a, 31 %div = sdiv i32 %mul, -2147483648 ret i32 %div } define i32 @test30(i32 %a) { ; CHECK-LABEL: @test30( ; CHECK-NEXT: ret i32 [[A:%.*]] ; %mul = shl nuw i32 %a, 31 %div = udiv i32 %mul, -2147483648 ret i32 %div } define <2 x i32> @test31(<2 x i32> %x) { ; CHECK-LABEL: @test31( ; CHECK-NEXT: ret <2 x i32> zeroinitializer ; %shr = lshr <2 x i32> %x, %div = udiv <2 x i32> %shr, ret <2 x i32> %div } define i32 @test32(i32 %a, i32 %b) { ; CHECK-LABEL: @test32( ; CHECK-NEXT: [[SHL:%.*]] = shl i32 2, [[B:%.*]] ; CHECK-NEXT: [[DIV:%.*]] = lshr i32 [[SHL]], 2 ; CHECK-NEXT: [[DIV2:%.*]] = udiv i32 [[A:%.*]], [[DIV]] ; CHECK-NEXT: ret i32 [[DIV2]] ; %shl = shl i32 2, %b %div = lshr i32 %shl, 2 %div2 = udiv i32 %a, %div ret i32 %div2 } define <2 x i64> @test33(<2 x i64> %x) { ; CHECK-LABEL: @test33( ; CHECK-NEXT: [[DIV:%.*]] = udiv exact <2 x i64> [[X:%.*]], ; CHECK-NEXT: ret <2 x i64> [[DIV]] ; %shr = lshr exact <2 x i64> %x, %div = udiv exact <2 x i64> %shr, ret <2 x i64> %div } define <2 x i64> @test34(<2 x i64> %x) { ; CHECK-LABEL: @test34( ; CHECK-NEXT: [[DIV:%.*]] = sdiv exact <2 x i64> [[X:%.*]], ; CHECK-NEXT: ret <2 x i64> [[DIV]] ; %neg = sub nsw <2 x i64> zeroinitializer, %x %div = sdiv exact <2 x i64> %neg, ret <2 x i64> %div } define i32 @test35(i32 %A) { ; CHECK-LABEL: @test35( ; CHECK-NEXT: [[AND:%.*]] = and i32 [[A:%.*]], 2147483647 ; CHECK-NEXT: [[MUL:%.*]] = udiv exact i32 [[AND]], 2147483647 ; CHECK-NEXT: ret i32 [[MUL]] ; %and = and i32 %A, 2147483647 %mul = sdiv exact i32 %and, 2147483647 ret i32 %mul } define <2 x i32> @test35vec(<2 x i32> %A) { ; CHECK-LABEL: @test35vec( ; CHECK-NEXT: [[AND:%.*]] = and <2 x i32> [[A:%.*]], ; CHECK-NEXT: [[MUL:%.*]] = udiv exact <2 x i32> [[AND]], ; CHECK-NEXT: ret <2 x i32> [[MUL]] ; %and = and <2 x i32> %A, %mul = sdiv exact <2 x i32> %and, ret <2 x i32> %mul } define i32 @test36(i32 %A) { ; CHECK-LABEL: @test36( ; CHECK-NEXT: [[AND:%.*]] = and i32 [[A:%.*]], 2147483647 ; CHECK-NEXT: [[MUL:%.*]] = lshr exact i32 [[AND]], [[A]] ; CHECK-NEXT: ret i32 [[MUL]] ; %and = and i32 %A, 2147483647 %shl = shl nsw i32 1, %A %mul = sdiv exact i32 %and, %shl ret i32 %mul } define <2 x i32> @test36vec(<2 x i32> %A) { ; CHECK-LABEL: @test36vec( ; CHECK-NEXT: [[AND:%.*]] = and <2 x i32> [[A:%.*]], ; CHECK-NEXT: [[MUL:%.*]] = lshr exact <2 x i32> [[AND]], [[A]] ; CHECK-NEXT: ret <2 x i32> [[MUL]] ; %and = and <2 x i32> %A, %shl = shl nsw <2 x i32> , %A %mul = sdiv exact <2 x i32> %and, %shl ret <2 x i32> %mul } define i32 @test37(i32* %b) { ; CHECK-LABEL: @test37( ; CHECK-NEXT: entry: ; CHECK-NEXT: store i32 0, i32* [[B:%.*]], align 4 ; CHECK-NEXT: br i1 undef, label [[LOR_RHS:%.*]], label [[LOR_END:%.*]] ; CHECK: lor.rhs: ; CHECK-NEXT: br label [[LOR_END]] ; CHECK: lor.end: ; CHECK-NEXT: ret i32 0 ; entry: store i32 0, i32* %b, align 4 %0 = load i32, i32* %b, align 4 br i1 undef, label %lor.rhs, label %lor.end lor.rhs: ; preds = %entry %mul = mul nsw i32 undef, %0 br label %lor.end lor.end: ; preds = %lor.rhs, %entry %t.0 = phi i32 [ %0, %entry ], [ %mul, %lor.rhs ] %div = sdiv i32 %t.0, 2 ret i32 %div } ; We can perform the division in the smaller type. define i32 @shrink(i8 %x) { ; CHECK-LABEL: @shrink( ; CHECK-NEXT: [[TMP1:%.*]] = sdiv i8 [[X:%.*]], 127 ; CHECK-NEXT: [[DIV:%.*]] = sext i8 [[TMP1]] to i32 ; CHECK-NEXT: ret i32 [[DIV]] ; %conv = sext i8 %x to i32 %div = sdiv i32 %conv, 127 ret i32 %div } ; Division in the smaller type can lead to more optimizations. define i32 @zap(i8 %x) { ; CHECK-LABEL: @zap( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i8 [[X:%.*]], -128 ; CHECK-NEXT: [[DIV:%.*]] = zext i1 [[TMP1]] to i32 ; CHECK-NEXT: ret i32 [[DIV]] ; %conv = sext i8 %x to i32 %div = sdiv i32 %conv, -128 ret i32 %div } ; Splat constant divisors should get the same folds. define <3 x i32> @shrink_vec(<3 x i8> %x) { ; CHECK-LABEL: @shrink_vec( ; CHECK-NEXT: [[TMP1:%.*]] = sdiv <3 x i8> [[X:%.*]], ; CHECK-NEXT: [[DIV:%.*]] = sext <3 x i8> [[TMP1]] to <3 x i32> ; CHECK-NEXT: ret <3 x i32> [[DIV]] ; %conv = sext <3 x i8> %x to <3 x i32> %div = sdiv <3 x i32> %conv, ret <3 x i32> %div } define <2 x i32> @zap_vec(<2 x i8> %x) { ; CHECK-LABEL: @zap_vec( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq <2 x i8> [[X:%.*]], ; CHECK-NEXT: [[DIV:%.*]] = zext <2 x i1> [[TMP1]] to <2 x i32> ; CHECK-NEXT: ret <2 x i32> [[DIV]] ; %conv = sext <2 x i8> %x to <2 x i32> %div = sdiv <2 x i32> %conv, ret <2 x i32> %div } ; But we can't do this if the signed constant won't fit in the original type. define i32 @shrink_no(i8 %x) { ; CHECK-LABEL: @shrink_no( ; CHECK-NEXT: [[CONV:%.*]] = sext i8 [[X:%.*]] to i32 ; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[CONV]], 128 ; CHECK-NEXT: ret i32 [[DIV]] ; %conv = sext i8 %x to i32 %div = sdiv i32 %conv, 128 ret i32 %div } ; When the divisor is known larger than the quotient, ; InstSimplify should kill it before InstCombine sees it. define i32 @shrink_no2(i8 %x) { ; CHECK-LABEL: @shrink_no2( ; CHECK-NEXT: ret i32 0 ; %conv = sext i8 %x to i32 %div = sdiv i32 %conv, -129 ret i32 %div } define i32 @shrink_no3(i16 %x) { ; CHECK-LABEL: @shrink_no3( ; CHECK-NEXT: ret i32 0 ; %conv = sext i16 %x to i32 %div = sdiv i32 %conv, 65535 ret i32 %div } ; This previously crashed when trying to simplify the zext/icmp this becomes. define <2 x i8> @PR34841(<2 x i8> %x) { ; CHECK-LABEL: @PR34841( ; CHECK-NEXT: ret <2 x i8> zeroinitializer ; %neg = and <2 x i8> %x, %div = udiv <2 x i8> , %neg ret <2 x i8> %div } ; X / (X * Y) -> 1 / Y if the multiplication does not overflow define i8 @div_factor_signed(i8 %x, i8 %y) { ; CHECK-LABEL: @div_factor_signed( ; CHECK-NEXT: [[TMP1:%.*]] = add i8 [[Y:%.*]], 1 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], 3 ; CHECK-NEXT: [[R:%.*]] = select i1 [[TMP2]], i8 [[Y]], i8 0 ; CHECK-NEXT: ret i8 [[R]] ; %a = mul nsw i8 %x, %y %r = sdiv i8 %x, %a ret i8 %r } ; X / (Y * X) -> 1 / Y if the multiplication does not overflow define <2 x i8> @div_factor_signed_vec(<2 x i8> %x, <2 x i8> %y) { ; CHECK-LABEL: @div_factor_signed_vec( ; CHECK-NEXT: [[TMP1:%.*]] = add <2 x i8> [[Y:%.*]], ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult <2 x i8> [[TMP1]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[TMP2]], <2 x i8> [[Y]], <2 x i8> zeroinitializer ; CHECK-NEXT: ret <2 x i8> [[R]] ; %a = mul nsw <2 x i8> %y, %x %r = sdiv <2 x i8> %x, %a ret <2 x i8> %r } ; X / (Y * X) -> 1 / Y if the multiplication does not overflow define i8 @div_factor_unsigned(i8 %x, i8 %y) { ; CHECK-LABEL: @div_factor_unsigned( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i8 [[Y:%.*]], 1 ; CHECK-NEXT: [[R:%.*]] = zext i1 [[TMP1]] to i8 ; CHECK-NEXT: ret i8 [[R]] ; %a = mul nuw i8 %y, %x %r = udiv i8 %x, %a ret i8 %r } ; X / (X * Y) -> 1 / Y if the multiplication does not overflow define <2 x i8> @div_factor_unsigned_vec(<2 x i8> %x, <2 x i8> %y) { ; CHECK-LABEL: @div_factor_unsigned_vec( ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq <2 x i8> [[Y:%.*]], ; CHECK-NEXT: [[R:%.*]] = zext <2 x i1> [[TMP1]] to <2 x i8> ; CHECK-NEXT: ret <2 x i8> [[R]] ; %a = mul nuw <2 x i8> %x, %y %r = udiv <2 x i8> %x, %a ret <2 x i8> %r } define i8 @udiv_common_factor(i8 %x, i8 %y, i8 %z) { ; CHECK-LABEL: @udiv_common_factor( ; CHECK-NEXT: [[C:%.*]] = udiv i8 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: ret i8 [[C]] ; %a = mul nuw i8 %z, %x %b = mul nuw i8 %z, %y %c = udiv i8 %a, %b ret i8 %c } define <2 x i8> @udiv_common_factor_commute1_vec(<2 x i8> %x, <2 x i8> %y, <2 x i8> %z) { ; CHECK-LABEL: @udiv_common_factor_commute1_vec( ; CHECK-NEXT: [[C:%.*]] = udiv <2 x i8> [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: ret <2 x i8> [[C]] ; %a = mul nuw <2 x i8> %x, %z %b = mul nuw <2 x i8> %z, %y %c = udiv <2 x i8> %a, %b ret <2 x i8> %c } define i8 @udiv_common_factor_commute2(i8 %x, i8 %y, i8 %z) { ; CHECK-LABEL: @udiv_common_factor_commute2( ; CHECK-NEXT: [[C:%.*]] = udiv i8 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: ret i8 [[C]] ; %a = mul nuw i8 %x, %z %b = mul nuw i8 %y, %z %c = udiv i8 %a, %b ret i8 %c } define i8 @udiv_common_factor_commute3(i8 %x, i8 %y, i8 %z) { ; CHECK-LABEL: @udiv_common_factor_commute3( ; CHECK-NEXT: [[C:%.*]] = udiv i8 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: ret i8 [[C]] ; %a = mul nuw i8 %z, %x %b = mul nuw i8 %y, %z %c = udiv i8 %a, %b ret i8 %c } ; Negative test: both mul must be 'nuw'. define i8 @udiv_common_factor_not_nuw(i8 %x, i8 %y, i8 %z) { ; CHECK-LABEL: @udiv_common_factor_not_nuw( ; CHECK-NEXT: [[A:%.*]] = mul i8 [[Z:%.*]], [[X:%.*]] ; CHECK-NEXT: [[B:%.*]] = mul nuw i8 [[Z]], [[Y:%.*]] ; CHECK-NEXT: [[C:%.*]] = udiv i8 [[A]], [[B]] ; CHECK-NEXT: ret i8 [[C]] ; %a = mul i8 %z, %x %b = mul nuw i8 %z, %y %c = udiv i8 %a, %b ret i8 %c } ; Negative test: both mul must be 'nuw'. define <2 x i8> @udiv_common_factor_not_nuw_vec(<2 x i8> %x, <2 x i8> %y, <2 x i8> %z) { ; CHECK-LABEL: @udiv_common_factor_not_nuw_vec( ; CHECK-NEXT: [[A:%.*]] = mul nuw <2 x i8> [[Z:%.*]], [[X:%.*]] ; CHECK-NEXT: [[B:%.*]] = mul <2 x i8> [[Z]], [[Y:%.*]] ; CHECK-NEXT: [[C:%.*]] = udiv <2 x i8> [[A]], [[B]] ; CHECK-NEXT: ret <2 x i8> [[C]] ; %a = mul nuw <2 x i8> %z, %x %b = mul <2 x i8> %z, %y %c = udiv <2 x i8> %a, %b ret <2 x i8> %c }