1; RUN: opt < %s -instsimplify -S | FileCheck %s 2 3; PR8862 4 5define i32 @shift1(i32 %A, i32 %B) { 6; CHECK-LABEL: @shift1( 7; CHECK-NEXT: ret i32 %A 8; 9 %C = lshr exact i32 %A, %B 10 %D = shl nuw i32 %C, %B 11 ret i32 %D 12} 13 14define i32 @shift2(i32 %A, i32 %B) { 15; CHECK-LABEL: @shift2( 16; CHECK-NEXT: [[C:%.*]] = lshr i32 %A, %B 17; CHECK-NEXT: [[D:%.*]] = shl nuw i32 [[C]], %B 18; CHECK-NEXT: ret i32 [[D]] 19; 20 %C = lshr i32 %A, %B 21 %D = shl nuw i32 %C, %B 22 ret i32 %D 23} 24 25define i32 @shift3(i32 %A, i32 %B) { 26; CHECK-LABEL: @shift3( 27; CHECK-NEXT: ret i32 %A 28; 29 %C = ashr exact i32 %A, %B 30 %D = shl nuw i32 %C, %B 31 ret i32 %D 32} 33 34define i32 @shift4(i32 %A, i32 %B) { 35; CHECK-LABEL: @shift4( 36; CHECK-NEXT: ret i32 %A 37; 38 %C = shl nuw i32 %A, %B 39 %D = lshr i32 %C, %B 40 ret i32 %D 41} 42 43define i32 @shift5(i32 %A, i32 %B) { 44; CHECK-LABEL: @shift5( 45; CHECK-NEXT: ret i32 %A 46; 47 %C = shl nsw i32 %A, %B 48 %D = ashr i32 %C, %B 49 ret i32 %D 50} 51 52define i32 @div1(i32 %V) { 53; CHECK-LABEL: @div1( 54; CHECK-NEXT: ret i32 0 55; 56 %A = udiv i32 %V, -2147483648 57 %B = udiv i32 %A, -2147483648 58 ret i32 %B 59} 60 61define i32 @div2(i32 %V) { 62; CHECK-LABEL: @div2( 63; CHECK-NEXT: ret i32 0 64; 65 %A = sdiv i32 %V, -1 66 %B = sdiv i32 %A, -2147483648 67 ret i32 %B 68} 69 70